mayor's message 152

OFFICE OF THE MAYOR

PETER B. CARLISLEMAYOR

CITY AND COUNTY OF HONOLULU530 SOUTH KING STREET, ROOM 300 * HONOLULU, HAWAII 96813

PHONE: (808) 768-4141 * FAX: (808) 768-4242 * INTERNET: wwwbo~~~uaov

DOUGLAS S. CHINMANAGING DIRECTOR

CHRYSTN K. A. EADSDEPUTY MANAGING DIRECTOR

October 28, 2011c-)

Subject: Resolution 11-1 82

Alternative Technologies for the Beneficial Reuse of Sewage Sludge

Dear Chair Martin and Councilmembers:

We are pleased to provide the enclosed report in response to the investigation requested

in Resolution 1 1-182:

1. Nine (9) hard copies of the AECOM Report: Alternative Technologies for theBeneficial Reuse of Sewage Sludge, October 2011; and

2. Two (2) hard copies of the CD disk with PDF files of the report.

In order to include a broader range of the alternatives and impacts of wastewatertreatment issues, information on technologies not specifically covered by the scope ofResolution 11-182 will be included in a supplemental report that will be available prior to theNovember 1

6th Public Works and Sustainability Committee hearing.

We are looking forward to working with the council to develop a viable solids handlingprogram at Sand Island Wastewater Treatment Plant that will be financially beneficial to thecommunity while resolving our two primary concerns: overcapacity of the current system, and aback-up in the event of a catastrophic failure or upset of the current single system.

Should you have any questions or concerns, please contact Deputy Director Ross

Tanimoto of the Department of Environmental Services, at 768-3482.

Very truly yours,

Enclosurescc: Tim Steinberger, Director/ENV

Douglas S. Chin, Managing Director

7~~A(~Peter B. CarlisleMayor

MAYOR’S MESSAGE 152

The Honorable Ernest Y. Martin, Chairand Councilmembers

Honolulu City Council530 South King Street, Room 202Honolulu, Hawaii 96813

(JI)

Alternative Technologies for theBeneficial Reuse of Sewage Sludge

Response to Resolution 11-182

Oahu, Hawaii

Final

October 2011

Prepared for:City & County of HonoluluDepartment of Environmental Services1000 Uluohia Street Suite 308Kapolei, Hawaii 96707

Prepared by:

1001 Bishop Street, Suite 1600Honolulu, Hawaii 96813

Alternative Technologies for the Beneficial Reuse of Sewage SludgeResponse to Resolution 11-182October 2011

Page i of xvii

CONTENTS

EXECUTIVE SUMMARY .......................................................................................................... vii

1.0 INTRODUCTION AND OVERVIEW ................................................................................1

1.1 Background .....................................................................................................................11.2 Purpose ...........................................................................................................................21.3 Objectives .......................................................................................................................21.4 Methodology ....................................................................................................................3

2.0 OVERVIEW OF SOLIDS TREATMENT AND PROCESSING ..........................................4

2.1 Terminology.....................................................................................................................42.2 Regulatory Background ...................................................................................................5

2.2.1 Land Application................................................................................................52.2.2 Emissions for Sewage Sludge Incineration (SSI)...............................................6

2.3 Current CCH Treatment and Processing Operations .......................................................62.4 Treatment and Processing Technology Classification ....................................................10

2.4.1 Digestion .........................................................................................................102.4.2 Composting .....................................................................................................112.4.3 Heat Drying Only .............................................................................................122.4.4 Incineration .....................................................................................................132.4.5 Gasification and Pyrolysis ...............................................................................142.4.6 Alternative Combustion ...................................................................................152.4.7 Alternative “Smokeless” Sludge Oxidation.......................................................152.4.8 Fuel Production ...............................................................................................162.4.9 Other Solids Technologies ..............................................................................162.4.10 Non-Solids Technologies ................................................................................162.4.11 Unknown Technologies ...................................................................................16

2.5 Technology Development Status ...................................................................................162.6 Consideration of Sludge Characteristics ........................................................................16

3.0 POTENTIAL TECHNOLOGIES AND VENDORS...........................................................18

3.1 Digestion Technologies .................................................................................................183.1.1 Omnivore ........................................................................................................183.1.2 Thermal Hydrolysis (TH) .................................................................................183.1.3 VERTAD .........................................................................................................18

3.2 Composting ...................................................................................................................183.2.1 Biozyme ..........................................................................................................183.2.2 Solorganics .....................................................................................................18

3.3 Heat Drying ...................................................................................................................183.3.1 Conventional Heat Drying ...............................................................................183.3.2 VitAg ...............................................................................................................19

3.4 Incineration ....................................................................................................................193.4.1 Fluid Bed Incineration (FBI) .............................................................................19

3.5 Gasification and Pyrolysis (Closed-Coupled) .................................................................193.5.1 Kruger BioCon + Energy Recovery System (ERS) ..........................................203.5.2 MaxWest .........................................................................................................203.5.3 Nexterra ..........................................................................................................20


Page ii of xvii

3.5.4 Prime Energy Gasification ...............................................................................213.5.5 Pyrobuster.......................................................................................................21

3.6 Gasification and Pyrolysis (Two Stage) .........................................................................213.6.1 Ascent BioEnergy ............................................................................................223.6.2 Carbon BioEngineers Inc. ...............................................................................223.6.3 D4 ...................................................................................................................223.6.4 HGE – Korea (a KBI Group) High Temperature Conversion of Waste (HTCW)

........................................................................................................................223.6.5 Integrated Environmental Technologies LLC – S4 Energy Solution .................233.6.6 Intellergy .........................................................................................................233.6.7 Kopf ................................................................................................................233.6.8 Kore Process (G2E! Green Earth Energy) .......................................................233.6.9 Nexterra ..........................................................................................................23

3.7 Alternative Combustion .................................................................................................233.7.1 Fabgroups Technologies – Plasma Assisted Sludge Oxidation (PASO) ..........233.7.2 Kunmin ............................................................................................................23

3.8 Alternative “Smokeless” Sludge Oxidation .....................................................................243.8.1 ATHOS Wet Air Oxidation (WAO) ...................................................................243.8.2 Sci-Fi SuperCritical Water Oxidation (SCWO) – AquaCritox™ ........................24

3.9 Fuel Production .............................................................................................................243.9.1 Enertech SlurryCarb™ ....................................................................................243.9.2 N-Viro International .........................................................................................243.9.3 Panatech .........................................................................................................24

3.10 Other Solids Technologies .............................................................................................243.10.1 Astec Thermal Remediation ............................................................................243.10.2 BioRenewables – Applied Filter Technologies .................................................243.10.3 HydroCell Dewatering .....................................................................................253.10.4 Ledcor .............................................................................................................253.10.5 PyroBioMethane™ ..........................................................................................25

3.11 Non-Solids Technologies ...............................................................................................253.11.1 Beneficial Active Microorganisms (BAM) .........................................................253.11.2 BioCleaner ......................................................................................................253.11.3 ECO-H2O ........................................................................................................253.11.4 Global Environmental Technology Services (GETS) .......................................263.11.5 SunPower .......................................................................................................26

3.12 Unknown Technologies .................................................................................................263.12.1 Ebara ..............................................................................................................263.12.2 Waste to Energy..............................................................................................26

4.0 EVALUATION CRITERIA ..............................................................................................27

4.1 Intent of the Resolution ..................................................................................................274.2 Onsite vs. Offsite Technologies .....................................................................................274.3 List of Criteria ................................................................................................................274.4 “Fatal Flaw” ...................................................................................................................284.5 Technology Development Status and Piloting................................................................294.6 Risks of Unknown Technologies ....................................................................................30

5.0 TECHNOLOGIES FOR FUTURE CONSIDERATION ....................................................33

6.0 SELECTION AND IMPLEMENTATION .........................................................................34


Page iii of xvii

6.1 Supplemental Report for Resolution 11-182: Alternative Technologies for the Treatmentand Minimization of Sewage Sludge .........................................................................................346.2 Island-wide Solids Master Plan ......................................................................................34

6.2.1 Island-wide Solids Quantity and Quality ..........................................................346.2.2 Solids Reduction at Smaller WWTPs (< 5 mgd) ..............................................346.2.3 Island-wide Transportation, Treatment, and Disposal ......................................346.2.4 Redundancy and Reliability for Processing and Disposal ................................356.2.5 Island-wide Solids Processing and Disposal Plan ...........................................35

6.3 Life-Cycle Cost Analysis ................................................................................................356.4 Schedule and Implementation .......................................................................................36

6.4.1 Pilot Testing ....................................................................................................366.4.2 Master Plan Timeline.......................................................................................366.4.3 Design and Construction .................................................................................366.4.4 Honouliuli and Sand Island Secondary Treatment ...........................................366.4.5 Facilities Planning for Kailua, Honouliuli, Sand Island, and Waianae WWTPs .36

TABLES

Table 2-1. Island-wide Solids Production ....................................................................................9Table 2-2. Characteristics of Different Thermal Processing Technologies .................................14Table 4-1. Technology Comparison ..........................................................................................31

FIGURES

Figure 2-1. Location of WWTPs and Waimanalo Gulch Landfill ..................................................7Figure 2-2. Honouliuli, Kailua, and Sand Island Process Flow Diagrams.....................................8Figure 2-3. Anaerobic Digester Schematic ................................................................................11Figure 3-1. Close-Coupled Gasification System for Energy Recovery .......................................20Figure 3-2. Two Stage Gasification System for Energy Recovery .............................................22

APPENDICES

Appendix A – Resolution 11-182Appendix B – RFIAppendix C – Technology Fact Sheets


Page iv of xvii

WORKS CITED

AECOM. (2011). Technical Memorandum Work Task 11.C: Solids Processing Technology.

Metcalf & Eddy. (2003). Wastewater Engineering Treatment and Reuse. 4th Edition.

US EPA. (1994). A Plain English Guide to the EPA Part 503 Biosolids Rule, EPA/832/R-93/003.Chapter 4 – Incineration of Biosolids.

US EPA. (2006). Emerging Technologies for Biosolids Management, EPA 832-R-06-005.

US EPA. (2011). “Standards of Performance for New Stationary Sources and EmissionGuidelines for Existing Sources: Sewage Sludge Incineration Units,” Federal Register / Vol. 76,No. 54, pp. 15372-15454, 40 CFR Part 60.

Water Environment Federation (WEF) Website. Glossary of Terms(http://www.wef.org/AWK/page.aspx?id=1951).


Page v of xvii

ACRONYMS/ ABBREVIATIONS

ATAD Autothermal Thermophilic Aerobic DigestionBAM Beneficial Active MicroorganismsBioconversion Facility In-vessel Bioconversion FacilityBOD Biological Oxygen DemandBTU British Thermal UnitsCCH City and County of HonoluluCEM Continuous Emission MonitoringCFR Code of Federal RegulationsCH4 MethaneCHP Combined Heat and PowerCO Carbon MonoxideCO2 Carbon Dioxidecu. ft. cubic feetcu. yd. cubic yardDB Design and BuildDBB Design, Bid, and BuildDBO Design, Build, and OperateDBOM Design, Build, Operate, and MaintainDBOOF Design, Build, Own, Operate, and FinanceDS Dry Solidsdtpd dry tons per dayENV Department of Environmental ServicesEPA Environmental Protection AgencyERS Energy Recovery SystemESPC Energy Savings Performance ContractFBI Fluid Bed IncinerationFOG Fats, Oils and GreaseG2E! Green Earth EnergyGE General ElectricGETS Global Environmental Technology ServicesH2 HydrogenH2O WaterIATS Innovative Anaerobic Treatment SystemIC Internal CombustionHER Hawaiian Earth Recycling, LLCHTCW High Temperature Conversion of Wastelb poundMABA Mid-Atlantic Biosolids AssociationMBR Membrane Bioreactormgd million gallons per dayMHI Multiple Hearth IncinerationMSAP Modified Static Aerobic PileMWe Mega Watt equivalentNBP National Biosolids PartnershipNEBRA North East Biosolids and Residuals AssociationO&M Operation & MaintenanceORC Organic Rankine CyclePASO Plasma Assisted Sludge Oxidation


Page vi of xvii

PEM Plasma Enhanced MelterPFRP Processes to Further Reduce Pathogenspsig pounds per square inch gaugePSRP Process to Significantly Reduce PathogensResolution Resolution 11-182RFI Request for InformationSCWO Supercritical Water OxidationSEP Supplemental Environmental ProjectsSOUR Specific Oxygen Uptake RateSPV Special Purpose VehicleSSI Sewage Sludge IncinerationSynagro Synagro WWT, IncTCOM Thermal Conversion of Organic MaterialTH Thermal HydrolysisTS Total SolidsTSK Tsukishima KikaiVS Volatile SolidsWAO Wet Air OxidationWEF Water Environment FederationWWTP Wastewater Treatment Plant


Page vii of xvii

EXECUTIVE SUMMARY

INTRODUCTION

BackgroundThe City and County of Honolulu (CCH) entered into the 1995 Consent Decree (Civil No. 94-00765DAE) with the State of Hawaii and the Environmental Protection Agency (EPA). As partof the 1995 Consent Decree, CCH committed to Supplemental Environmental Projects (SEPs)which included spending at least $10 million on beneficial sludge reuse. The result of the 1995Consent Decree was a contract in 2004 between CCH and Synagro WWT, Inc. (Synagro) inwhich Synagro would design/build/operate an In-vessel Bioconversion Facility (BioconversionFacility) at the Sand Island Wastewater Treatment Plant (WWTP) to convert the sludge into apellet fertilizer. The main components of the Synagro In-vessel Bioconversion Facility are anegg-shaped digester for anaerobic digestion, two centrifuges for dewatering, and a dryer forpelletizing.

The 2010 Consent Decree between CCH, State of Hawaii, and EPA included the upgrade of theSand Island and Honouliuli WWTPs to full secondary treatment. In addition, CCH is evaluatingalternatives to the Waimanalo Gulch Landfill by conducting an Island-wide Biosolids MasterPlan.

Currently the egg shaped digester at Sand Island WWTP is at full capacity resulting in the needto consider either expansion of existing operations or alternative technologies for processingand treatment. On June 28, 2011, the City Council signed Resolution 11-182 (herein referred toas the Resolution), which stated concerns about the current bioconversion facility including:

(1) Public health and safety(2) Impact to businesses and residents(3) Visual blight and impacts to tourism(4) Marketability of fertilizer pellets(5) Reputation and credibility(6) The cost to construct the existing bioconversion facility was over $40 million, including

cost overruns exceeding $7 million, and the projected cost of the second facility wasbudgeted at $26 million

As part of an ongoing contract with ENV, AECOM began work in August 2010 on a LeewardRegion Solids Master Plan. In June 2011 ENV requested AECOM expand the effort to preparean Island-Wide Solids Master Plan. The Island-wide Solids Master Plan is evaluating theexisting solids treatment and disposal at all the CCH operated WWTPs with the goal ofrecommending improvements or upgrades at these WWTPs. On July 1, 2011 AECOM wasfurther tasked by ENV to investigate and prepare a report in response to Resolution 11-182,which requested the administration to:

“...investigate alternative technologies for the beneficial reuse of sewage sludge otherthan the technology used at the Sand Island WWTP’s bioconversion facility that will besustainable and less harmful to the environment, including technologies successfullyused in Europe, Asia and North America by companies with good reputations forcredibility... to the end that the Council [would] work with the City administration


Page viii of xvii

expeditiously to implement a safe and healthful alternative to the Synagro technology soas to ensure that any necessary construction may commence as soon as possible.”

Overview of Solids Handling OperationsCCH currently operates nine WWTPs on Oahu including Honouliuli, Kahuku, Kailua, Laie,Paalaa Kai, Sand Island, Wahiawa, Waianae, and Waimanalo WWTP. Currently, Honouliuli,Kailua, and Waianae WWTPs’ sludge goes through anaerobic digestion for stabilization andcentrifuges for dewatering. The biosolids are then hauled to Waimanalo Gulch Landfill fordisposal. Synagro Bioconversion Facility at Sand Island WWTP also has anaerobic digestionfor stabilization, followed by dewatering, and drying for pelletization. The pellets produced atSynagro Bioconversion Facility have been used as a fertilizer at agricultural farms, golf courses,and parks. The dried product from the Synagro facility is either beneficially reused as a fertilizerproduct for land application or hauled to Waimanalo Gulch Landfill for disposal. Synagroindicated that currently most of their generated product is being beneficially used withoutrevenue. The Kahuku, Paalaa Kai, Wahiawa, and Waimanalo WWTPs haul liquid waste to thelarge facilities for further treatment. The Laie WWTP has an onsite composting facility that isoperated by CCH staff. The compost that has been approved for distribution is used by theMormon Church that owns the WWTP for agricultural purposes and the compost that is notapproved for distribution (mostly due to metal content) is disposed of at the Waimanalo GulchLandfill. Figure 1 shows the location of the existing WWTPs, currently available solids outletsand transfer of solids between the various facilities.

Table 1 provides an estimate of solids production at each of the WWTPs as well as some keyaspects associated with treatment and disposal at each.

Purpose and ObjectivesThe purpose of this report is to respond to the Resolution by identifying potential alternativesludge processing technologies for the beneficial reuse of sewage sludge other than thetechnology used at Sand Island WWTP. Some of the technologies included in this report arefrom vendors that responded to a Request for Information, were known by AECOM or hadapproached the CCH and/or the City Council directly.

The outcome of this report is a list of technologies meeting the requirements of the Resolutionfor consideration as part of the ongoing island-wide solids planning effort. The intent of thistechnology listing is to have appropriate technologies to evaluate in considering island-widesludge management needs. This report is not intended to be a decision making document thatrecommends a best solution. Some additional factors that will need to be determined as part ofany evaluation and selection process would likely include:

An assessment of a particular alternative technology specific to the WWTP with respectto the facilities already existing there.

Capital and O&M costs specific to the WWTP in which it is being evaluated for. Implementation timeline for planning, design, permitting, procurement, construction and

startup. Compatibility of technology with overall Island-wide Solids Master Plan New development and increased future capacity needs Planned upgrades at the existing WWTPs (i.e. upgrade to secondary treatment)

Alternative Technologies for the Beneficial Reuse of Sewage Sludge Response to Resolution 11-182 October 2011

Page ix of xvii

It should be noted that technology and process selection for implementation at any of the nine WWTPs will need to be looked at from an island-wide perspective due to the issues of combining/transportation of solids between WWTPs as well as the identified end user needs and beneficial use limitations. Other key elements that were considered include reliability and redundancy planning in the event that a WWTP treatment unit (i.e. centrifuge or digester) or solids outlet (i.e. landfill or composting facility) is temporarily out of service.

Table 1 - Island-Wide Solids Production

WWTP Average

Flow1 (mgd)

Stabilization Solids

Production2 (dtpd)

State of Solids

Dewatering Method

Solids Distribution

Honouliuli 25.92 Anaerobic Digester 7.28 Cake Centrifuge

Waimanalo Gulch Landfill

(~7 mi)

Kahuku 0.19 Aerobic Digester 0.26 Liquid None Kailua Regional

WWTP (~34 mi)

Kailua Regional

11.49 Anaerobic Digester

2.65 Cake Centrifuge Waimanalo

Gulch Landfill (~32 mi)

Laie 0.46 Clarigester ---3 Compost Composting Mormon Church/


Paalaa Kai 0.09 Aerobic Digester 0.05 Liquid None Honouliuli

WWTP (~21 mi)

Sand Island 61.29 Anaerobic Digester 9.21 Dried Pellets Centrifuge/Dryer

Class A Fertilizer Pellets

Reuse/ Waimanalo


Wahiawa4 1.64 Not Stabilized 2.00 Liquid None Honouliuli

WWTP (~17 mi)

Waianae 3.31 Anaerobic Digester 0.44 Cake Centrifuge


(~8 mi)

Waimanalo 0.55 Anaerobic Digester 0.26 Liquid None Kailua Regional

WWTP (~33 mi) 1 Source: City and County of Honolulu, Dept of Environmental Services, Wastewater Management website (FY 2011). Million gallons per day (mgd) 2 Source: Annual Biosolids Production Reports – January 1 to December 31, 2010, Division of Wastewater Treatment and Disposal, ENV. Dry tons per day (dtpd)

3 Dry weight is not available (no percent solids data). Laie WRF produced a total of 1,056 cu. yd. of compost that was disposed at the landfill. This is approximately 727.6 wet

tons (based on a measured unit weight of 51 lbs/cu. ft.) Source: Note 8, Annual Biosolids Production Reports – January 1 to December 31, 2010, Division of Wastewater Treatment and Disposal, ENV 4

Wahiawa is currently being upgraded to an MBR facility, so solids characteristics will change when the new processes are in operation.


Page x of xvii

Insert Figure 1 - Location of WWTPs and Waimanalo Gulch Landfill


Page xi of xvii

Identification and Classification of TechnologyPotential technologies and technology vendors were identified by several methods. The initiallisting of technologies was developed using known technologies and technology vendors thatare currently active within the municipal wastewater industry. This includes technologies andvendors identified as part of the ongoing island-wide solids master planning effort that could beimplemented at large (>5 mgd) WWTPs. Additional technologies and vendors were obtainedthrough a formal Request for Information (RFI) and solicitation process through variousprofessional organizations. Technology vendors that had previously contacted the CCH weresent the RFI to provide key information required for evaluation.

Technology ClassificationThe identified vendors and their technologies covered a wide range of treatment and processingtypes. In order to facilitate an organized approach to determining applicability many of thevendors were organized by the general classification or technology category which bestdescribed the process using standard industry terminology as described in the followingparagraphs. It should be noted that some solution providers responding to the RFI were notactually equipment manufacturers or suppliers. These solution providers were often systemintegrators that provided an alternative means of financing, often involving a rate paybacksystem or power purchase agreement to recuperate initial construction costs. As discussedfurther in the report the economics and life-cycle cost comparison of the various alternatives willbe conducted as part of the Island-wide Solids Master Plan and as such only the specifictechnologies proposed by any respective vendor are considered, irrespective of financingmethodology.

The categories used for technology classification are identified below and described in detail inthe following report. In some instances an entire technology category was not considered forfuture consideration since the category itself did not meet the defined requirements. Thetechnology classifications are as follows with the more established technologies listed first,followed by the newer and innovative processes:

Digestion Composting Heat Drying Only Incineration Gasification and Pyrolysis (Closed-Coupled) Gasification and Pyrolysis (Two Stage) Alternative Combustion Alternative “Smokeless” Sludge Oxidation Fuel Production Other Technologies

Technology Development StatusThe processes are generally classified in the industry based on the stage of development. Inthis report, the technologies are classified either as either “concept”, “emerging”,“demonstration”, or “established” technology as defined below:

1. Concept technologies are ones that are not proven at pilot and/or small scales.


Page xii of xvii

2. Emerging technologies are proven at pilot/small scale but are not proven at a full scaleinstallation.

3. Demonstration technologies are proven at one to three full scale installations.

4. Established technologies are proven at more than three sites.

“Concept” technologies are not considered further in this evaluation unless the vendor wouldlike to conduct pilot testing at one of the WWTPs at no expense to CCH. Pilot testing will notguarantee that the technology would be chosen; however, a successful demonstration wouldreclassify the development status from “Concept” to “Emerging”.

TECHNOLOGY EVALUATIONAs stated in the Resolution, this report “…investigate[d] alternative technologies for thebeneficial reuse of sewage sludge other than the technology used at the Sand Island WWTP’sbioconversion facility that will be sustainable and less harmful to the environment, includingtechnologies successfully used in Europe, Asia and North America by companies with goodreputations for credibility...” As such, technologies other than anaerobic digestion, drying only,and pelletization are considered if the byproducts are beneficially reused or energy is beinggenerated for on-site use.

The beneficial reuse technologies considered are focused on the on-site treatment of solids atthe larger facilities (Honouliuli, Kailua, and Sand Island WWTPs). Although composting isconsidered a beneficial reuse, the product may be considered a soil amendment or fertilizer andthe Resolution states that “…uses of sewage sludge byproducts for purposes other thanfertilizer should be explored...” The offsite incineration at H-power may be considered abeneficial reuse of the sludge; however, the energy produced would not be beneficial to theWWTP. Therefore, offsite technologies including composting by HER and incineration at H-Power are considered in the Supplemental Report for Resolution 11-182: AlternativeTechnologies for the Treatment and Minimization of Sewage Sludge.

Evaluation CriteriaThe evaluation criteria for the technologies are as follows:

Is it a Solids Handling Process? Process Input Requirement Responded to RFI? Status of Technology Development Ease of Operation Regulatory and Permitting Impact Footprint Ability and Willingness of Vendor to Pilot Is Upstream Anaerobic Digestion Required or Desired for Energy Production? End Product Ability to Produce Electricity Beneficial Byproducts Other Materials That Can Be Accepted Is Existing or Different Drying Required? Consumables Capital Cost for 25 dtpd Facility (Vendor Provided)


Page xiii of xvii

O&M Cost (Vendor Provided) Does Capital and O&M estimate include upstream processing required such as drying?

It should be noted that capital and O&M costs presented are unverified vendor estimates andmay not include or take into account site requirements, ancillary items, and cost of installation inHawai‘i. In addition, some of the vendors do not have full scale installations.

In order to further consider appropriate technologies for solids processing, technologies withone or more of the listed “fatal flaws” below were not considered appropriate for futureconsideration.

Technologies that are not considered “solids processing based” Technologies unable to process the 25 dtpd minimum amount of sludge Technologies where the main product is material that requires land application Technologies that are currently at the conceptual level Technologies where the vendor actively declined to respond to the RFI. Technologies where the providing vendor did not acknowledge or respond to the RFI.

Table 2 presents all technologies that were evaluated in this report, with the technologiesrecommended for future consideration highlighted. The listed and evaluated technologiesexclude those used at the Synagro Bioconversion Facility. As the table shows, there is a widerange of technologies included. The list and development status of technologies/vendors will becontinually updated during the island-wide master planning process.

Risks of Unknown TechnologiesAs many of the “appropriate” technologies considered are not “established” and there are limitedinstallations world-wide, the risk of unknown information is high. There may be unknowndisadvantages and unknown costs for the newer technologies. For “concept” technologies, theunknowns include unknown results of a pilot test and unknown costs and it may be difficult toprove the claims of the vendor. For “emerging” technologies, there is the unknown of upsizingto a full scale installation for both results and costs. For “demonstration” technologies, theunknown is if the results from the full scale installation can be reproduced.


Page xiv of xvii

Insert Table 2 Screened Technologies Page 1


Page xv of xvii

Insert Table 2 Screened Technologies Page 2


Page xvi of xvii

SELECTION AND IMPLEMENTATION

Supplemental Report of Additional TechnologiesIn addition to this document, the Supplemental Report for Resolution 11-182: AlternativeTechnologies for the Treatment and Minimization of Sewage Sludge will be completed byNovember 11, 2011 to identify other solids technologies that may be appropriate for solidstreatment but may not directly meet the Resolution requirements. These technologies may beapplicable to both the small and large WWTPs. Similar to this report, the Supplemental Reportfor Resolution 11-182: Alternative Technologies for the Treatment and Minimization of SewageSludge will list technologies to consider for further evaluation during the master planningprocess.

Further Evaluation and Life-Cycle Cost AnalysisFor each technology classification a single technology/vendor will be used as a representativefor comparison purposes during the island-wide planning effort. This evaluation should not beviewed as selecting the vendor for CCH rather selecting the category that best suits CCHcurrent and future needs. The ultimate selection of the vendor/technology would be based oncompetitive bidding by the appropriate method such as design, bid and build (DBB), design andbuild (DB), design, build and operate (DBO), design, build, operate and maintain (DBOM), anddesign, bid, own, operate and finance (DBOOF).

Further evaluation of technologies will be qualitatively conducted during the island-wide studyevaluation using the criteria listed below in order to arrive at a group of technologies that aremost appropriate for solids processing.

Expected capital cost Expected O&M cost Ease of operation and maintenance Energy producing potential Sustainable technology (measured as CO2e potential) Public perception of the facility

Although some of the information above is presented in the current comparison tables, it shouldbe noted that the values listed are for a “generic” plant that produces 25 DT/day and not aspecific WWTP operated by CCH. A more detailed evaluation and check should be performedto ensure that comparable scope items are included in the capital and O&M costs and that the“cost” factors are the same for all options based on the local island costs. For example,Nexterra provided a capital and O&M cost for their gasification systems but did not include thedrying component as a part of the cost. In addition, the scope boundary for an O&M estimateshould be thoroughly checked in the detailed evaluation to ensure that any comparison madefor further screening is based on an “apples to apples” comparison. Moreover, inclusion of anyboundaries set for labor and hauling costs should be the same for all screened technologies.This type of thorough check has not been completed at this time and will be included in theIsland-Wide Solids Master Planning for the “short-listed” technologies.

Island-wide Solids Master PlanningCCH is currently underway with an Island-wide Solids Master Plan to evaluate the existingsolids treatment and disposal at all the CCH operated WWTPs. The goal of this master plan isto recommend improvements or upgrades at these WWTPs. The solids recommendations from


Page xvii of xvii

the Honouliuli, Kailua, and Sand Island facilities plans will be incorporated into the Island-wideSolids Master Plan. Key elements of the master planning effort are outlined below:

Island-wide Solids Quantity and Quality Estimates - Determine existing and projectfuture solids quantity and quality at each WWTP.

Solids Reduction at Smaller WWTPs (< 5 mgd) - Determine the cost effectiveness ofonsite solids reduction treatment to reduce hauling, offsite treatment, and/or disposalcosts for the smaller WWTPs, especially the WWTPs that haul liquid waste to the largerfacilities.

Island-wide Transportation, Treatment, and Disposal - Evaluate the cost effectiveness oftransportation, treatment, and disposal options for all nine CCH operated WWTPs.

Redundancy and Reliability for Processing and Disposal - Determine the reliability andback-up options for the planned solids processing and disposal in the event that oneoption is unavailable due to mechanical failure or other causes.

Island-wide Solids Processing and Disposal Plan - Incorporate the findings of theprevious reports to recommend upgrades to the existing solids processing and disposalat each WWTP.

Schedule and Implementation

Pilot Testing – If conducted, pilot testing of technologies is anticipated to take at least 18to 24 months. This includes 12 months of data collection once the pilot testing facility isin operation.

Master Plan Timeline - The master plan timeline is as follows:o Complete Sampling and Testing - January 2012o Island-wide Solids Quantity and Quality Estimates – April 2012o Solids Reduction at Smaller WWTPs – May 2012o Island-wide Transportation, Treatment, and Disposal – May 2012o Redundancy and Reliability for Processing and Disposal – August 2012o Island-wide Solids Processing and Disposal Plan – December 2012

Design and Construction - Design and construction scheduling depends on theconstruction and phasing recommendations in the Island-wide Solids Processing andDisposal Plan. It is anticipated that design for each project would take one year andprocurement and construction would take two to three years. It is assumed that someprojects may run concurrently.

Honouliuli and Sand Island Secondary Treatment - The Honouliuli and Sand IslandWWTPs are anticipated to begin full secondary treatment by 2024 and 2035,respectively, in accordance with the 2010 Consent Decree. The solids quantity isexpected to increase substantially when these WWTPs become secondary WWTPs.Master planning efforts along with any near term design and construction will take intoconsideration the timing and future anticipated needs at both facilities.

Facilities Planning for Kailua, Honouliuli, Sand Island, and Waianae WWTPs – The netoutcome of Facilities Plans and Island-wide Solids Master Plan will be coordinated to bein agreement regarding the proposed solids handling facilities at the referenced WWTPs


Page 1 of 36

1.0 INTRODUCTION AND OVERVIEW

1.1 BackgroundThe City and County of Honolulu (CCH) entered into the 1995 Consent Decree (Civil No. 94-00765DAE) with the State of Hawaii and the Environmental Protection Agency (EPA). As partof the 1995 Consent Decree, CCH committed to Supplemental Environmental Projects (SEPs)which included spending at least $10 million on beneficial sludge reuse. The result of the 1995Consent Decree was a contract in 2004 between CCH and Synagro WWT, Inc. (Synagro) inwhich Synagro would design/build/operate an In-vessel Bioconversion Facility (BioconversionFacility) at the Sand Island Wastewater Treatment Plant (WWTP) to convert the sludge into apellet fertilizer. The main components of the Synagro In-vessel Bioconversion Facility are anegg-shaped digester for anaerobic digestion, two centrifuges for dewatering, and a dryer forpelletizing.

The 2010 Consent Decree between CCH, State of Hawaii, and EPA included the upgrade of theSand Island and Honouliuli WWTPs to full secondary treatment. In addition, CCH is evaluatingalternatives to the Waimanalo Gulch Landfill by conducting an Island-wide Biosolids MasterPlan.

Currently, the egg shaped digester at Sand Island WWTP is at full capacity resulting in the needto consider either expansion of existing operations or alternative technologies for processingand treatment. On June 28, 2011, the City Council signed Resolution 11-182 (herein referred toas the Resolution and provided in Appendix A), which stated concerns about the currentbioconversion facility including:

(1) Public health and safety(2) Impact to businesses and residents(3) Visual blight and impacts to tourism(4) Marketability of fertilizer pellets(5) Reputation and credibility(6) The cost to construct the existing bioconversion facility was over $40 million, including

cost overruns exceeding $7 million, and the projected cost of the second facility wasbudgeted at $26 million

As part of an ongoing contract with ENV, AECOM began work in August 2010 on a LeewardRegion Solids Master Plan. In June 2011 ENV requested AECOM expand the effort to preparean Island-Wide Solids Master Plan. The Island-wide Solids Master Plan is evaluating theexisting solids treatment and disposal at all the CCH operated WWTPs with the goal ofrecommending improvements or upgrades at these WWTPs. On July 1, 2011 AECOM wasfurther tasked by ENV to investigate and prepare a report in response to Resolution 11-182,which requested the administration to:

“...investigate alternative technologies for the beneficial reuse of sewage sludge otherthan the technology used at the Sand Island WWTP’s bioconversion facility that will besustainable and less harmful to the environment, including technologies successfullyused in Europe, Asia and North America by companies with good reputations forcredibility... to the end that the Council [would] work with the City administrationexpeditiously to implement a safe and healthful alternative to the Synagro technology soas to ensure that any necessary construction may commence as soon as possible.”


Page 2 of 36

1.2 PurposeThe purpose of this report is to respond to the Resolution by identifying potential alternativesludge processing technologies for the beneficial reuse of sewage sludge other than thetechnology used at Sand Island WWTP. Some of the technologies included in this report arefrom vendors that responded to a Request for Information (RFI), were known by AECOM or hadapproached the CCH and/or the City Council directly. It should be noted that this report is notintended to be a decision making document and it is only intended to identify appropriatetechnologies to consider moving forward and provide a high level comparison. A more detailedand thorough analysis will be conducted with the island-wide study.

1.3 ObjectivesThe objectives of this report include:

Assemble a formal RFI, provided in Appendix B, for a generic WWTP that produces 25dry tons per day (dtpd) of solids but does not use the treatment process currently atSand Island WWTP.

Submit the RFI to the National Biosolids Partnership (NBP), the Mid Atlantic BiosolidsAssociation (MABA), and the North East Biosolids and Residuals Association (NEBRA)to post on their websites and pass on to their respective members to allow experts in thefield to comment and provide information about innovative and emerging technologies.

Submit the RFI to various technology vendors that directly contacted CCH or CityCouncil.

Compile a list of technologies or vendors and information that was received from the RFIprocess.

Compile a list of criteria to evaluate the technologies or vendors. Compile a list of technologies that should be further evaluated in the upcoming Island-

wide Solids Master Planning.

The outcome of this report is a list of technologies meeting the requirements of the Resolutionfor consideration as part of the ongoing island-wide solids planning effort. The intent of thistechnology listing is to have appropriate technologies to evaluate in considering island-widesludge management needs. This report is not intended to be a decision making document thatrecommends a best solution. Some additional factors that will need to be determined as part ofany evaluation and selection process would likely include:

An assessment of a particular alternative technology specific to the WWTP with respectto the facilities already existing there.

Capital and O&M costs specific to the WWTP in which it is being evaluated for. Implementation timeline for planning, design, permitting, procurement, construction and

startup. Compatibility of technology with overall Island-wide Solids Master Plan New development and increased future capacity needs Planned upgrades at the existing WWTPs (i.e. upgrade to secondary treatment)

It should be noted that technology and process selection for implementation at any of the nineWWTPs will need to be looked at from an island-wide perspective due to the issues ofcombining/transportation of solids between WWTPs as well as the identified end user needsand beneficial use limitations. Other key elements that were considered include reliability and


Page 3 of 36

redundancy planning in the event that a WWTP treatment unit (i.e. centrifuge or digester) orsolids outlet (i.e. landfill or composting facility) is temporarily out of service.

1.4 MethodologyThe vendors contacted during the compilation of technologies for this report includedtechnologies known by AECOM, technologies included in Work Task 11.C – Solids ProcessingTechnology (April 2011), technologies from vendors that contacted CCH and City Councildirectly, and vendors that responded to the posting on NBP, MABA, and NEBRA websites. Thevendors were sent and asked to respond to the RFI. The information collected from the RFIwas compiled and screening criteria were developed to determine technologies and vendorsthat may be applicable for beneficial reuse of sewage sludge at the larger WWTPs.


Page 4 of 36

2.0 OVERVIEW OF SOLIDS TREATMENT AND PROCESSINGThe following section provides background information that was taken into account whenevaluating the different technology vendors. This section discusses common industryterminology, provides some regulatory background and summarizes the islands currentbiosolids plan. This section also provides background on the technology classification used tocategorize the vendors as well as a summary of how the technology development was ratedand the impact of site specific sludge characteristics.

2.1 TerminologyThis section defines terminology used in this report.

Aerobic – Describes a condition where bacteria are living or occurring in the presenceof oxygen. Many secondary treatment processes occur aerobically and sewage sludgecan be digested under aerobic conditions to stabilize sewage sludge and generatebiosolids.Anaerobic – Describes a condition where bacteria are living or occurring in the absenceof oxygen. Many WWTPs digest their sludge anaerobically for stabilization, generatingbiosolids. Anaerobic process also produces methane (CH4) as a byproduct that can bebeneficially used for energy production.Biosolids – Describes Solid materials resulting from wastewater treatment that meetsgovernment criteria for beneficial use, such as for fertilizer. To be classified as biosolidsthe sewage sludge must have undergone additional stabilization such as digestion,composting, drying or alkaline stabilization to meet federal and state standards forbeneficial use. The stabilization requirements to convert sewage sludge to Biosolids aredefined by the EPA under 40 CFR (Code of Federal Regulations) Part 503Cake – Informal term used to describe dewatered sludge or dewatered biosolids comingoff of a dewatering device such as a belt filter press or centrifuge.Class A Biosolids – Describes biosolids that are processed to the requirements definedby the EPA under 40 CFR, Part 503 with regards to pathogen and vector attractionreduction requirements. The goal of developing class A standards was to provide aquality of biosolids where pathogens in sewage sludge (including enteric viruses,pathogenic bacteria and viable helminth ova) were below detectable limits as defined inthe 1992 regulation.Class B Biosolids – Describes biosolids that are processed to the requirements definedby the EPA under 40 CFR, Part 503 with regards to pathogen and vector attractionreduction requirements. The goal of developing class B standards was to provide aquality of biosolids where pathogens were below levels considered likely to pose a threatto public health and the environment under the specific use conditions. Applying ClassB sludge involves site use restrictions to minimize the potential for human or animalexposure to Class B solids for a set period of time.Dewatering – The process of extracting or removing water from sludge or slurryDrying – To remove water through the means of evaporationDry Tons – A unit of measurement representing only the dry mass of a substance. Onedry ton is equal to 2,000 dry pounds (lbs) (Example: 10.0 dry tons at 35% solids 28.6wet tons)In-vessel Bioconversion Facility – A term used by Synagro to describe the full sludgeprocessing system at Sand Island including digestion, dewatering and drying. Theprocess as installed converts thickened sewage sludge to a dry pelletized biosolidsproduct that meets Class A requirements and can be marketed as a fertilizer product.


Page 5 of 36

In-vessel Composting Facility – A composting system with integral materials handlingand in-vessel mixing and aeration.Solids Minimization – Process that reduces the mass and volume of sludge for furtherprocessing, beneficial reuse or dispositionPelletizing – A process that generates a uniform round or cylindrical dry biosolidsproduct (a pellet). Some dryers are designed with back mixing, screening or othermechanisms to produce pellets at the dryer’s outlet. A second process can also beadded to convert a non-uniform dried material to pellets.Percent Solids – The percentage of a sludge or biosolids total mass that is solidmaterial. The percent water fraction is equal to one minus the percent solidsSludge - Solid matter that settles to the bottom of septic tanks or WWTP sedimentation;must be disposed of by bacterial digestion or other methods of stabilization. Sludge canalso be pumped out for land disposal or incineration.Stabilization – A process that is applied to sludge for the purpose of reducingpathogens, eliminating offensive odors, and inhibiting, reducing or eliminating thepotential for putrefication (EPA’s 503 documents).Volatile Solids (VS) - Materials, generally organic, that can be driven off from a sampleby heating, usually to 550 °C (1022 °F); nonvolatile inorganic solids (ash) remain1.Wet Tons - A unit of measurement representing only the total mass of a substanceincluding the mass of water. One wet ton is equal to 2,000 wet lbs (example: 10.0 wettons 3.5 dry tons at 35% solids)

2.2 Regulatory Background2.2.1 Land Application

For Land Application under EPA Federal Regulations (Under 40 CFR Part 503), processedresiduals to produce biosolids are grouped into two categories depending on pathogenreduction: Class A and Class B. Class A biosolids that meet metal contamination limits aredeemed Exceptional Quality. Class A biosolids are treated to reduce the presence of pathogensto very low levels and can be used without any pathogen related restrictions. Class B biosolidsare also treated to reduce pathogens but to levels that are not as low as Class A biosolids. Tocompensate, there are a number of site restrictions for land application of Class B biosolidsincluding buffer zones and restrictions to public access which are intended to safeguard publichealth. Class B beneficial reuse is effectively restricted to agricultural applications. Sewagesludge that is not processed to either Class A or Class B standards is not considered biosolids.

To meet Class A requirements a process must be used to reduce pathogen levels to certaincriteria. The process must also include a vector attraction reduction step either before or co-current with the pathogen reduction step which is meant to stabilize the biosolids. Currently theEPA defines six alternatives to meet Class A pathogen requirements. The objective of the sixalternatives is to reduce pathogen densities below detectable limits as defined when theregulations were written. Class A pathogen requirements are met by Alternative 1 through hightemperature treatments based on set time and temperature curves. Alternative 2 requires highpH and high temperature processes (alkaline treatment) for producing class A. A process thatdoes not meet one of the specific alternatives can achieve Class A through extensive pathogen,enteric virus and helminth ova testing through Alternative 3. Alternative 4 also allows for ClassA of biosolids that are treated in an unknown process through extensive pathogen testing similar

1 Water Environment Federation (WEF) Website. Glossary of Terms (http://www.wef.org/AWK/page.aspx?id=1951).


Page 6 of 36

to what is required in Alternative 3. Alternative 4 is mainly targeted for solids that are stockpiledor stored for extended periods in lagoons. Alternative 5 defines several Processes to FurtherReduce Pathogens (PFRP) which include processes such as heat drying, composting, and pre-pasteurization among others. Alternative 6 allows for other processes to be classified as beingequivalent to an existing PRFP defined in Alternative 5.

To meet Class B requirements, a process must be used to reduce pathogen levels but not toquite as low of a level as it required for Class A. The EPA currently defines three alternatives tomeet Class B. Alternative 1 is to perform fecal coliform testing to ensure it is below the definedthreshold. Alternative 2 is to use a Process to Significantly Reduce Pathogens (PSRP) such asaerobic digestion, air drying, anaerobic digestion, composting, or lime stabilization. Biosolidscan also be classified as Class B by proving that a process is equivalent to a PSRP.

Vector attraction reduction is also an important component of both Class A and Class Brequirements. A vector is defined by the EPA as “any living organism capable of transmitting apathogen from one organism to another either mechanically (by simply transporting thepathogen) or biologically by playing a specific role in the life cycle of the pathogen.” Vectors forsewage sludge pathogens include insects, rodents, and birds. There are several definedmethods for meeting vector attraction reduction. The vector attraction reduction methods aregenerally related to VS destruction, specific oxygen uptake rate (SOUR) tests, aerobicrequirements, pH requirements, percent dryness, or through a method of applying the biosolidsto the land where it would prevent the attraction of vectors.

2.2.2 Emissions for Sewage Sludge Incineration (SSI)

A major concern for any SSI technology is the impact of the process on air quality andpotentially rigorous air permitting requirements. In March 2011, New Sewage SludgeIncinerators Rules regulated under 40 CFR, Part 60 and Section 129 of the Clean Air Act wereenacted. From the new rules, all sewage sludge incinerators will now require a Title V airpermit. The ruling requires stricter air permitting and monitoring requirements than waspreviously required under the previous rules which were regulated under Section 112 of theClean Air Act. The new regulations are specific for Multiple Hearth Incineration (MHI) and FluidBed Incineration (FBI); however, they may also impact the gasification technologies discussedherein. It is expected that two stage gasification technologies may be exempt from the rulingsince the process includes syngas cleaning. However, there is not a biosolids gasificationsystem installed in the US that has been permitted since the new rules were enacted so there isnot currently a precedent set to know exactly how concept and emerging combustion orgasification technologies will be regulated.

2.3 Current CCH Treatment and Processing OperationsCCH currently operates nine WWTPs on Oahu including Honouliuli, Kahuku, Kailua, Laie,Paalaa Kai, Sand Island, Wahiawa, Waianae, and Waimanalo WWTP. Figure 2-1 shows thelocations of the WWTPs along with the location of the Waimanalo Gulch Landfill. Figure 2-2shows the process flow for the CCH’s three largest WWTPs; Kailua, Honouliuli, and Sand IslandWWTPs.


Page 7 of 36

Figure 2-1. Location of WWTPs and Waimanalo Gulch Landfill


Page 8 of 36

Figure 2-2. Honouliuli, Kailua, and Sand Island Process Flow Diagrams

Alternative Technologies for the Beneficial Reuse of Sewage Sludge Response to Resolution 11-182 October 2011

Page 9 of 36

Under normal operating conditions, all WWTPs except for Wahiawa WWTP stabilize their solids via aerobic or anaerobic digestion. Currently, Honouliuli, Kailua, and Waianae WWTPs sludge goes through anaerobic digestion for stabilization and centrifuges for dewatering. The biosolids are then hauled to Waimanalo Gulch Landfill for disposal. The Synagro Bioconversion Facility at Sand Island WWTP also has anaerobic digestion for stabilization, followed by dewatering, and drying for pelletization. The pellets produced at the Synagro Bioconversion Facility have been used as a fertilizer at agricultural farms, golf courses, and parks. The pellets that do not meet the specifications or cannot be marketed are hauled to Waimanalo Gulch Landfill for disposal. The Kahuku and Waimanalo WWTPs haul liquid waste to Kailua WWTP and Paalaa Kai and Wahiawa WWTPs haul liquid waste to Honouliuli WWTP for further treatment. The Wahiawa WWTP is currently being upgraded with membrane bioreactors (MBRs); the solids quality and quantity will differ once the MBRs are in service. The Laie WWTP has an onsite windrow composting facility that is operated by CCH staff but owned by the Mormon Church. The compost that has been approved for distribution is used by the Mormon Church for agricultural purposes and the compost that is not approved for distribution (mainly due to metal content) is disposed of at the Waimanalo Gulch Landfill. Table 2-1 presents information on the Island-wide Solids Production.

Table 2-1. Island-wide Solids Production

WWTP Average

Flow1 (mgd)

Stabilization Solids

Production2 (dtpd)

State of Solids

Dewatering Method

Solids Distribution

Honouliuli 25.92 Anaerobic Digester 7.28 Cake Centrifuge


(~7 mi)

Kahuku 0.19 Aerobic Digester 0.26 Liquid None Kailua Regional

WWTP (~34 mi)

Kailua Regional

11.49 Anaerobic Digester

2.65 Cake Centrifuge Waimanalo


Laie 0.46 Composting ---3 Compost Belt Filter Press Mormon Church/


Paalaa Kai 0.09 Aerobic Digester 0.05 Liquid None Honouliuli

WWTP (~21 mi)

Sand Island 61.29 Anaerobic

Digester/Dryer

9.21 Dried Pellets Centrifuge/Dryer

Class A Fertilizer Pellets

Reuse/ Waimanalo


Wahiawa4 1.64 Not Stabilized 2.00 Liquid None Honouliuli

WWTP (~17 mi)

Waianae 3.31 Anaerobic Digester 0.44 Cake Centrifuge


(~8 mi)

Waimanalo 0.55 Anaerobic Digester 0.26 Liquid None Kailua Regional

WWTP (~33 mi) 1 Source: City and County of Honolulu, Dept of Environmental Services, Wastewater Management website (FY 2011) 2 Source: Annual Biosolids Production Reports – January 1 to December 31, 2010, Division of Wastewater Treatment and Disposal, ENV

3 Dry weight is not available (no percent solids data). Laie WRF produced a total of 1,056 cu. yd. of compost that was disposed at the landfill. This is approximately 727.6 wet

tons (based on a measured unit weight of 51 lbs/cu. ft.) Source: Note 8, Annual Biosolids Production Reports – January 1 to December 31, 2010, Division of Wastewater Treatment and Disposal, ENV 4

Wahiawa WWTP is currently being upgraded to an MBR facility, so solids characteristics may change when the new processes are in operation.


Page 10 of 36

2.4 Treatment and Processing Technology ClassificationThe identified vendors and their technologies covered a wide range of treatment and processingtypes. In order to facilitate an organized approach to determining applicability many of thevendors were organized by the general classification or technology category which bestdescribed the process using standard industry terminology as described in the followingparagraphs. It should be noted that some solution providers responding to the RFI were notactually equipment manufacturers or suppliers. These solution providers were often systemintegrators that provided an alternative means of financing, often involving a rate paybacksystem or power purchase agreement to recuperate initial construction costs. As discussedfurther in the report, the economics and life-cycle cost comparison of the various alternatives willbe conducted as part of the Island-wide Solids Master Plan and as such only the specifictechnologies proposed by any respective vendor are considered, irrespective of financingmethodology.

The technology classifications are presented with the more established technologies listed first,followed by the newer and innovative processes. This section summarizes the technologyclassifications. Additional information is provided in Appendix C.

2.4.1 Digestion

Digestion is decomposition of organic matter in sewage treatment. There are two main types ofdigestion; aerobic digestion (with air) or anaerobic digestion (without air). Both aerobic andanaerobic digestion are well established technologies that have been used throughout theworld. CCH currently has two facilities that include aerobic digestion and five facilities that useanaerobic digestion.

Aerobic digestion is a well proven process and is similar to activated sludge processes used insecondary treatment. Aerobic digestion uses aerobic microbes to decompose organic matter,stabilize sewage sludge and generate biosolids. Aerobic digestion is most commonly practicedat plants less than 5 mgd. Aerobic digestion typically yields high VS destruction, has a lowbiological oxygen demand (BOD) concentration in the side streams from dewatering, producesa relatively odorless stable end product, maintains a high nutrient value in the biosolids, issimple to operate and involves relatively low capital costs. The aerobic process, however,requires a lot of air input which requires a high electrical consumption. The resulting liquidbiosolids are typically difficult to dewater. The process is also very dependent on operatingconditions and does not produce a useful energy producing byproduct (CH4). ConventionalAerobic digestion produces Class B biosolids. A system can also be designed as anAutothermal Thermophilic Aerobic Digestion (ATAD) process which uses the exothermic energyin the biological process to heat the reactor to thermophilic conditions generating Class Abiosolids. Since Aerobic Digestion is energy intensive and not suitable for large plants, it is notconsidered an appropriate solution for CCH’s larger plants and will not be discussed further inthis report.

Anaerobic digestion is another well proven process that involves the decomposition of organicmatter and inorganic matter in the absence of oxygen. The decomposition process produces adigester gas that consists of mostly CH4 (~65%) and carbon dioxide (CO2) (~35%). Anaerobicdigestion of municipal wastewater solids can, in many cases, produce sufficient digester gas tomeet the energy requirements of digestion and other plant operations. Therefore, due to theemphasis on energy conservation and recovery, the process continues to be advantageous forstabilizing sewage sludge. In principle, the conversion of organic matter to CO2 and CH4reduces biological solids leaving the digestion process. Digestion can reduce the total volume


Page 11 of 36

of solids to be dewatered and the polymer cost for dewatering. There are a number of digestiondesigns which can produce Class A and Class B biosolids, allowing for flexibility with reuseoptions, by meeting the requirements of EPA’s Part 503 Rule. Anaerobic digestion doeshowever, require a relatively large footprint when compared to alternative technologies and canhave a high capital cost. Also since anaerobic digestion is a biological process, it slowlyrecovers from an upsets. The process may also accumulate with scum and grit which could bedifficult to clean and foaming may be problematic as well. Downstream dewatering centratemay also be high in ammonia and could require separate treatment if there are tight nitrogenlimits. The process may also be susceptible to struvite formation which can cause operation andmaintenance issues with scaling in pipes, heat exchangers, valves and other equipment.Figure 2-3 shows the anaerobic digester schematic.

Figure 2-3. Anaerobic Digester Schematic

(Figure from www. meniscus.co.uk)

The biogas produced can be captured and treated for various energy recovery uses includingheat and electrical power in combined heat and power (CHP) system. CCH currently operatesanaerobic digesters at the Kailua, Honouliuli, Sand Island, and Waianae WWTPs and CCH isevaluating CHP options at these WWTPs in upcoming Energy Savings Performance Contracts(ESPCs).

2.4.2 Composting

Composting is a well-established process in which biodegradable material is decomposed byaerobic microorganisms in a controlled environment. The heat generated in compostingpasteurizes the product and significantly reduces pathogens. The heat generated also drives offwater vapor, further dewatering the product and reducing reuse volume. Composting that isperformed according to regulatory guidelines produces Class A Biosolids. Composting that isperformed properly can produce a nuisance-free humus-like material. The three differentmethods of composting typically used for wastewater sludge are aerated static pile, windrowand in-vessel composting.

Composting is a relatively simple process to operate and all composting processes generallyinclude common basic steps. First, the dewatered sludge is mixed with an amendment and/or


Page 12 of 36

bulking agent to increase porosity of the mixture and provide a carbon source to improve thedegradability of the compost. A rule of thumb for composting is to have a 25:1 to 35:1 ratio ofcarbon to nitrogen (mass basis). The resulting mixture is piled or placed in a vessel wheremicrobial activity causes the temperature to rise starting the “active composting” period. Thedesired temperature required for optimal operation and end quality vary based on the method ofcomposting and desired use of the end product. The key is to keep the material aerated to allowaerobic bacteria to work. After the “active composting” period is complete, the material is curedand distributed. Static pile and windrow composting are generally manual in operation and canbe operator intensive. In-vessel composting is generally a proprietary process provided by avendor or solution provider and is typically more automated and sophisticated than othercomposting methods.

Composting is an established technology with more than 300 installations nationwide. CCHcurrently operates the Laie WWTP which has an onsite composting facility. Due to the largefootprint requirements required for composting, CCH may not be able to implement an onsitecomposting facility at any other WWTP, however, off-site composting such as the systemproposed by Hawaiian Earth Recycling, LLC (HER) may be a feasible alternative. It would bethe responsibility of the composting company to market and distribute the product.

2.4.3 Heat Drying Only

Dryers come in several types, all of which operate with the goal of decreasing water content inwastewater sludge. Drying is typically used in the last stage of solids processing and is done incombination with a dewatering process. Dryers are typically fed with dewatered sludge atapproximately 15-35% dry solids (DS) and dry the biosolids to 90-95% DS. Sludge fed to dryerscan be either undigested or digested dewatered sludge, although some vendors haverestrictions with handling undigested primary sludge. As a general rule upstream digestion istypically recommended for primary sludge due to potential for odors in the final product. Dryersare able to produce Class A biosolids which can be beneficially used. Even if beneficial use isnot the desired option, the drying process greatly reduces the storage, transportation anddisposal cost since it significantly lowers the water content and reduces the weight.

Dryers are classified into three categories: 1) direct (convective) dryers, 2) indirect (conductive)dryers, and 3) combination direct/indirect dryers. Direct dryers use a drying medium such as hotair, which comes in direct contact with the sludge to increase the sludge temperature throughconvective heat transfer and evaporate the water in the sludge. Indirect dryers use a mediumsuch as hot oil or steam that heats the sludge through a conducting surface, so that the heatingmedium does not come in direct contact with the sludge. Combination dryers use two mediums,one which comes in direct contact with the sludge and one which heats the sludge through amembrane.

Most dryers are flexible and able to use most fuel sources such as natural gas, propane, dieselfuel or fuel oil. The dryers can also be equipped with burners that can directly use digester orother biogas sources, although there typically needs to be a supplemental or standby fuel inaddition. Some dryers use the fuel to directly heat hot air for drying while others may use a heattransfer fluid such as thermal oil, steam or hot water to provide heat to the dryer. The ability touse waste heat from other processes, such as a CHP system, depends on the specific dryerdesign and operating temperature. Lower temperature dryers that utilize a heat transfer fluidare generally better suited for low temperature waste heat recovery applications. Unless wasteheat or fuel that results as a byproduct from another process (i.e. CH4) is used, the operatingcost of drying can be high due to the cost of consuming a large amount of fossil fuels.


Page 13 of 36

There are potential risks and safety concerns with dryers related to fire and explosion potentialdue to combustible gases and dust. Safety systems such as a sprinkler system or water delugesystem are typically incorporated in the event an emergency condition such as high temperatureor carbon monoxide (CO) level is detected. Some dryers may also contain fugitive dustmonitoring, explosion relief panels and nitrogen purge systems. The safety system incorporatedtypically depends on the type of dryer used and designed operating conditions. The dry productcan also be a risk for fires and explosions if large amounts of product are stored in a storagevessel or silo. Specific safety precautions such as temperature and CO or CO2 monitoring, andinert air (nitrogen) blankets are typically required.

Drying is an established technology that requires a relatively small footprint and does notgenerally require chemical additives. CCH currently has a third party operated direct rotarydrum dryer at the Sand Island WWTP that produces class A pellets that are marketed forbeneficial reuse. The pellets are currently beneficially reused for agricultural purposes althoughthey can also be beneficially reused for energy production. Dryers can be capital cost intensiveand are more complicated to operate than other stabilization technologies.

2.4.4 Incineration

Incineration or advanced thermal oxidation is a combustion reaction that occurs in the presenceof excess oxygen. Incineration is the most commonly used thermal conversion processpracticed for sewage sludge today. FBI and MHI are established technologies and are the mostcommon types of incineration used for sewage sludge. MHI is now considered an outdatedtechnology and very few if any new systems are being constructed.

Since MHIs and FBIs are mature technologies, there is extensive experience with bothoperation and applying air emission control technologies. With a full array of 204 incinerationinstallations (144 MHIs and 60 FBIs) in operation throughout the country, there is a substantialdatabase of background data available with which owners, vendors, and regulators are able topredict the expected performance of any proposed incinerator. With the future implementationof new EPA emission limits and standards for MHIs and FBIs, it would take some time for allparties to recalibrate their design guidelines to the stringent new standards. However, ingeneral, vendors and engineers would be able to provide system guarantees to meet theemission limits.

Incineration achieves significant volume reduction and produces a byproduct that is inert, sterileand free of pathogen and toxic organic compounds. Incineration can also be equipped withprovisions for energy recovery and electrical generation. Incineration systems do not requireprior stabilization and raw dewatered sludge feed is typically preferred since it has a higher heatvalue than digested biosolids. Incinerators also require a relatively small footprint. The Airpermitting of a new incineration system, however, can be tedious and difficult especially with thenew SSI rules and may not be feasible for a nonattainment2 area. Incinerators have a highcapital cost and may require supplemental fossil fuel consumption if the feed is low in heat valueor the moisture content is too high. The process can also be very complicated requiring asophisticated operating staff and high operation and maintenance costs. The new SSI rulesalso require a continuous emission monitoring (CEM) for multiple pollutants. Besides tedious airpermitting and monitoring requirements, incineration is not popular in many places and may besubject to public opposition. Furthermore the ash product residual from incineration many times

2 Nonattainment area per the EPA’s website is defined as “Any area that does not meet (or that contributes to ambient air quality ina nearby area that does not meet) the national primary or secondary ambient air quality standard for the pollutant.”


Page 14 of 36

requires landfill disposal unless a beneficial use can be found such as road construction orconcrete production.

CCH had a MHI installed at Honouliuli and Sand Island WWTPs that are currently not inoperation. CCH had difficulty obtaining and maintaining an air permit for the MHIs. Due to thesignificant volume reduction potential and energy generation, FBI is a good candidatetechnology to consider in the island wide study; however, regulatory or public pressures coulddrive CCH away from this technology option.

2.4.5 Gasification and Pyrolysis

Gasi cation is an established process for converting organic waste to a fuel gas called syngas,and has been practiced since the 1800s to generate fuel gas from coal and other biomass.Syngas is composed mainly of CO, CO2, hydrogen (H2) and CH4 and has a low heating value of120-150 British Thermal Units (BTU)/cubic feet (cu. ft.), which is approximately 25% of the heatvalue of biogas generated from anaerobic digestion. The heat value of the syngas can beincreased if steam or enriched air (mostly oxygen) is used as the gasification medium.

Although gasification is common in many industries, gasification of biosolids is still considered inthe emerging/demonstration phase depending on the vendor and process configuration.Currently, there are several biosolids gasification installations worldwide. One of the largerdifferences between traditional organic materials used as the fuel source in gasification andbiosolids is the higher ash content of biosolids.

Pyrolysis is also an established technology used in the chemical industry to produce charcoal,activated carbon and methanol. Similar to gasification, pyrolysis at high temperatures generatesa combustible gas, pyrolysis gas, with a low heating value but also can be used to generatechar and oil. Pyrolysis is actually the first step that occurs in both gasification and combustionreactions. Pyrolysis of biosolids is still considered an emerging/demonstration phasetechnology.

Table 2-2 shows the operating difference between combustion, gasification and pyrolysis andthe main byproducts from each. Most vendors claim that the emissions from a gasification orpyrolysis process will be lower than what is produced in an incineration technology.

Table 2-2. Characteristics of Different Thermal Processing TechnologiesParameter Combustion Gasification Pyrolysis

Temperature (°F) 1,650-2,000 1,100-1,800 390-1,100

O2 Supplied > Stoichiometric(Excess Air)

< Stoichiometric(Limited Air) None

By-Products Flue Gas (CO2, H2O)and Ash

Syngas (CO, H2)and Ash or Char

Pyrolysis Gas, Oils,Tars and Char

It should be noted that the characteristics of the solids byproduct can vary in compositiondepending on the operating conditions of the reactor. For incineration or complete combustion,all of the organics and fixed carbons are burned leaving an inert ash. Pyrolysis systems;however, leave a char product that still contains fixed carbons, phosphorous, potassium andmicronutrients that may have an agricultural value. Gasification systems may produce either ora mixture of both depending on the systems operating conditions. In all cases the volume ofresiduals left over for disposition are significantly reduced. The operating conditions of the


Page 15 of 36

reactor plus the composition of the sewage sludge may also contribute to the sludge fusingtogether in the reactor or forming “clinkers.” Clinkering is reported to be a potential issue forbiomass and biosolids used in gasification and pyrolysis.

Although gasification and pyrolysis are relatively new technologies in the biosolids market theyhave potential to offer a solution that generates green energy while eliminating the dependenceon land application and landfilling biosolids. Biosolids gasification and pyrolysis do not generallyrequire upstream digestion and undigested sludge is typically preferred since undigested sludgehas a higher heating value. Like incineration, gasification and pyrolysis also destroy pathogensand organic toxic compounds in the feed. Gasification and pyrolysis systems have a highcapital cost and require a sophisticated operating staff.

To effectively gasify or pyrolyze biosolids, most commercially available systems require thebiosolids be dried to greater than 75% solids content and be in granular form. Pelletization isnot required for gasification or pyrolysis; however, certain degree of uniformity in the driedgranular material along with low dust content is required. The required dryness depends on thetechnology. The energy required for drying is typically supplied by the gasification process.Energy can also be recovered from waste heat, such as a CHP system, if available onsite.

There are two forms of recovering energy from gasification: closed couple gasification and twostage gasification. Energy generation from biosolids through pyrolysis also allows for similarenergy recovery methods. To increase the energy generation, other forms of biomass can beused as additional fuel to the gasification or pyrolysis process; such as treated fats, oil, andgrease (FOG) and/or yard (wood) waste. WWTP screenings can also be used as a fuel sincescreenings contain plastic and paper material with high BTU fuel value compared to sludge.

2.4.6 Alternative Combustion

The alternative combustion category is established in this paper to provide a group oftechnologies that utilize an alternative to FBI or MHI to combust sludge. This technology groupis established since the alternative combustion technologies for sewage sludge are not wellestablished and thus should not be categorized with traditional SSI (MHI and FBI). Thealternate combustion designs generally claim some improvement over traditional incinerationsuch as higher efficiency, lower cost, or a technical innovation such as a unique upstreamdrying process or use of a plasma arch torch.

Currently, CCH has a contract with Covanta to produce electricity at the H-Powerincineration/combustion facility. CCH is currently considering hauling solids to H-Power forincineration. This is an option for beneficial reuse; however, the WWTP itself would not receiveany benefits of the energy production.

2.4.7 Alternative “Smokeless” Sludge Oxidation

The alternative “smokeless” sludge oxidation process is used to categorize technologies thatoperate under extremely high pressures and use air or purified oxygen to oxidize the organiccomponents of sewage sludge. These technologies include wet air oxidation and supercriticalwet air oxidation. The term “smokeless” is applied since the technology vendors claim that theirsystems operate without actually burning the sludge so a smokestack is not required. Thevendors claim that these processes reduce the sludge to only the inert material and allow forbeneficial reuse of sludge through the production of energy and electricity. These technologies,however, are not well proven, operate at extremely high pressures, and only a few installationsexist worldwide. The processes are also generally compared to the Zimpro wet air oxidation


Page 16 of 36

process that was widely used a few decades ago but has since become less popular due toissues with the process and odors.

2.4.8 Fuel Production

The fuel production process is used to categorize technologies that claim to convert sewagesludge to a coal or fuel substitute. Most of these processes simply require a drying step toproduce a pellet or granular material with a high BTU value. Each process, however, wasdesigned with an upstream processing step that added some additional chemicals to the fuel orwas designed to improve the efficiency of the drying step. The product from most of theseprocesses is not expected to be much different than the pellets currently produced at theSynagro Bioconversion Facility at the Sand Island WWTP. For this type of process to besuccessful, a market has to be developed and end users have to agree to purchase or take inthe fuel substitute.

2.4.9 Other Solids Technologies

The “other solids technologies” category is meant to capture any additional solids technology,vendor, or solution provider that was identified or contacted CCH during the evaluation and didnot fit into one of the previously described categories. This group included third partyintegrators that did not offer any unique technologies but instead offered alternative projectdelivery or financing options of previously described technologies or combinations of several oftechnologies.

2.4.10 Non-Solids Technologies

This category is meant to capture any technology that was not considered biosolids based.Several vendors and solution providers contacted CCH to promote alternatives to current,secondary, and/or tertiary treatment.

2.4.11 Unknown Technologies

This category is meant to capture any technology that was added to the list but no specificinformation about the particular process was provided.

2.5 Technology Development StatusThe processes are generally classified in the industry based on the stage of development. Inthis report, the technologies are classified as either “concept”, “emerging”, “demonstration”, or“established” technology as defined below:

1. Concept technologies are ones that are not proven at pilot and/or small scales.

2. Emerging technologies are proven at pilot/small scale but are not proven at a full scaleinstallation.

3. Demonstration technologies are proven at one to three full scale installations.

4. Established technologies are proven with more than three full scale installations.

2.6 Consideration of Sludge CharacteristicsThe sludge characteristics at each WWTP must be considered as certain technologies may bebetter suited for different sludge. For example, the Sand Island wastewater has been noted tocontain high sulfides. In addition, the level of wastewater treatment at each WWTP must alsobe considered when evaluating various solids processing technologies as Sand Island WWTPonly has primary treatment and Honouliuli WWTP has partial secondary treatment and bothWWTPs are to be upgraded to full secondary treatment in accordance with the 2010 Consent


Page 17 of 36

Decree. Laboratory analysis of each WWTP’s sewage sludge will be performed during an earlyphase of the island wide study to characterize each WWTP’s sewage sludge. The specificcharacteristics of the sludge are needed to properly design the systems, determine mostappropriate reuse options, and may be used to help mitigate potential problems that could beencountered with a full scale operation.


Page 18 of 36

3.0 POTENTIAL TECHNOLOGIES AND VENDORSThe list of potential technologies and vendors are a combination of known vendors, vendors thatcontacted CCH and/or the City Council, and vendors that responded to the RFI. These vendorsare grouped by the technology classifications in alphabetical order. This section lists thepotential technologies and vendors and provides a very brief summary of the technology. Moredetailed information about each process is provided in the Technology fact sheets located inAppendix C.

3.1 Digestion Technologies3.1.1 Omnivore

Omnivore is a high solids mechanical mixer for anaerobic digestion. Enhanced anaerobicdigestion technology is discussed in more detail in the Supplemental Report for Resolution 11-182: Alternative Technologies for the Treatment and Minimization of Sewage Sludge.

3.1.2 Thermal Hydrolysis (TH)

TH is a sludge conditioning process that precedes anaerobic digestion to produce a Class Aproduct and make biosolids more digestible. TH is discussed in more detail in the SupplementalReport for Resolution 11-182: Alternative Technologies for the Treatment and Minimization ofSewage Sludge.

3.1.3 VERTAD

VERTAD is an ATAD process that converts municipal primary and secondary sludge to Class Abiosolids using an in-ground vertical aerated shaft. The vendor claims the process can achievegreater than 40% VS destruction with a SRT of less than 4 days. VERTAD is discussed in moredetail in the Supplemental Report for Resolution 11-182: Alternative Technologies for theTreatment and Minimization of Sewage Sludge.

3.2 Composting3.2.1 Biozyme

BioZyme provides a combined static pile and windrow composting process, called ModifiedStatic Aerobic Pile (MSAP) that utilizes a proprietary “organic catalyst” that they claim enhancesand improves the composting process. With the Biozyme process, the composting process isreported to occur at a faster rate and with less turning than traditional windrow composting.

3.2.2 Solorganics

Solorganics provides a process that combines Solar Drying and In-vessel composting toproduce a Class A Fertilizer product. The use of solar drying beds reduces the moisture contentdown to 60% to promote conditions suitable for “active composting.”

3.3 Heat Drying3.3.1 Conventional Heat Drying

Conventional heat drying is a well-established technology. There are a number of vendors andsolution providers that provide various types of drying systems. Direct drying is currentlypracticed at the Sand Island WWTP. This technology is mentioned herein for comparison butalone does not directly address the Resolution since the purpose of this paper is to identifyalternative technologies.


Page 19 of 36

3.3.2 VitAg

VitAg is a process that converts dewatered biosolids into fertilizer. The process consists ofseveral preprocessing steps consisting of pugmills, a hydrolysis vessel and chemical andnutrient addition. The slurry is dried in a rotary drum dryer before being distributed as afertilizer.

3.4 Incineration3.4.1 Fluid Bed Incineration (FBI)

As mentioned in Section 2.4.4, MHIs are considered an outdated technology; therefore, onlyFBIs will be considered in further. FBI is a well-established technology and there are a numberof well-established vendors that have an established history and track record with incineration.

3.5 Gasification and Pyrolysis (Closed-Coupled)Close coupled gasification as shown in Figure 3-1, is when the syngas from the gasification orpyrolysis system is directly oxidized without a syngas cleaning step. Syngas oxidation generatesa high temperature flue gas, approximately 1,800°F, which can be used for thermal heatrecovery. The energy recovered from the flue gas can be used as the energy source to dry thebiosolids to the desired dryness and thus minimize or eliminate the need for fossil fuels (e.g.,natural gas or fuel oil). The hot flue gas can also be used as an energy source for generatingelectricity through the use of steam turbines or an Organic Rankine Cycle (ORC). The cooledflue gas must then be treated and scrubbed before being emitted to the atmosphere. The levelof treatment required depends on the site specific air permit. At this time it is unsure how thenew SSI rules will effect close coupled gasification since there is not current project to set aprecedent but these systems may be held to similar permitting and monitoring requirements.More stringent air permitting, monitoring and control requirements will increase O&M costsassociated with these types of systems.

The close coupled method of electrical production is commonly practiced on other types ofbiomass gasification; however, this system is not common for biosolids since it is generallymore economical to use the energy to offset the drying energy requirement. The closedcoupled mode of energy recovery is considered commercially developed and is currentlypracticed in the biosolids facilities in Buffalo, MN (Kruger/Veolia) and in Sanford, FL (MaxWest).

Energy and mass balances for close coupled gasification systems show that there is sufficientenergy in undigested dewatered sludge (depending on the heat content and the percent solidsof the dewatered cake) to completely dry (obtain > 90% dryness) the material without the needfor auxiliary fuel. Thus, the close coupled gasi cation process is considered ideal for harnessingthe energy from the dried biosolids and recycling this energy to dry the biosolids, producingenergy efficient or an energy neutral drying processes. For anaerobically digested biosolids,some of the volatile material is consumed and converted to biogas which reduces the calorificvalue of the biosolids. Since the calorific value of digested biosolids is lower, a higher dewateredsolid content is required to achieve an energy neutral drying and gasification processes.


Page 20 of 36

Figure 3-1. Close-Coupled Gasification System for Energy Recovery

The amount of fuel or biosolids to be processed, and the amount of excess energy in the hotflue gas generated, will dictate which form of CHP technology can be practically used togenerate power and in some cases, low grade waste heat. Another factor which determines thetype of CHP that can be used is the size of the facility and the goals for energy recovery. Smallto medium facilities, with a goal of producing electricity may use a technology such as the ORCwith 10-20% electricity efficiency that is capable of recovering energy from excess amount offlue gas generated. Larger facilities with similar goals may select high pressure steam turbineswith approximately 15-38% electrical efficiency. There are practical economic and non-economic criteria which helps determine the appropriate size and type of system.

3.5.1 Kruger BioCon + Energy Recovery System (ERS)

The Kruger BioConTM ERS system is a package system that consists of a BioCon Belt Dryer, areciprocating grate furnace, heat recovery equipment and emission control equipment. Energyfor the belt drying process is supplied via the biosolids furnace through a close coupledconfiguration.

3.5.2 MaxWest

The MaxWest system is a package close coupled gasification system that includes the dryer,gasification system, heat recovery and emission controls. MaxWest only offers their systemthrough a DBOOF business model.

3.5.3 Nexterra

Nexterra in Kamloops, BC offers a fixed-bed, updraft gasification system. Nexterra can offergasification systems in both the two stage (with syngas cleaning) and close coupled (withoutsyngas cleaning) heat recovery configurations. Nexterra prefers to only offer their gasificationsystem, energy recovery and flue gas/syngas cleaning system and typically does not prefer toinclude a dryer in their scope. Nexterra has stated their preferred size range is at least 25 dtpd.


Page 21 of 36

3.5.4 Prime Energy Gasification

Prime Energy offers a fixed-bed, updraft gasification system with a close coupled heat recoveryconfiguration. Prime Energy’s technology is primarily geared for larger plants and they havestated that their system becomes more economical at sizes larger than 25 dtpd.

3.5.5 Pyrobuster

The pyrolysis technology marketed by Pyrobuster (an Eisenmann Company) consists of a twostage rotary chamber that operates under different operating conditions with respect to oxygencontent. The biosolids are screw fed into the first chamber which operates at relatively hightemperatures with no oxygen present to pyrolyze the biosolids and the remaining coke is sent tothe second chamber where it is oxidized to an inert ash. The resulting pyrolysis gas is extractedfrom the system to be used as a fuel source in a separate post combustion chamber. ThePyrobuster system can be coupled with most dryers and the dryer can either be suppliedthrough Eisenmann or purchased separately.

3.6 Gasification and Pyrolysis (Two Stage)In two stage gasification and pyrolysis systems, the syngas produced from gasifying the driedbiosolids is cleaned and used as a fuel source for multiple purposes such as process heat andelectrical production. The cleaned syngas can also be further refined to a marketable fuelproduct such as diesel, CH4, H2 or methanol. Cleaning the syngas is required to remove sulfur,siloxanes, and other contaminants that could damage the downstream processing equipment orcontribute to air pollution. The level of cleaning required is dependent on the downstreamprocess and air permitting regulations. The syngas cleaning process is not fully developed forthe application of biosolids and currently considered in the emerging/demonstration phase.Syngas cleaning, however, is commercially practiced in the coal and biomass industry but on amuch larger scale. It is believed that energy recovery from the production of clean syngas willnot be held to the new stringent SSI regulations that were enacted in spring of 2011. A genericprocess flow diagram of a two stage gasification/pyrolysis system is provided in Figure 3-2.

There is only one known commercial facility worldwide, located at Balingan Germany’s WWTP,currently operating two stage gasification using biosolids; however, a second facility is currentlybeing commissioned in Mannheim, Germany. The gasification and syngas cleaning processesat both facilities were supplied by Kopf located in Germany. The cleaned syngas is fired in areciprocating gas engine to produce electricity and heat. The syngas conditioning technologyutilized at both WWTPs is still considered in the demonstration phase.

Two stage gasification is also being developed by Nexterra. Nexterra does not currently havefull scale experience with biosolids gasification but has successfully piloted biosolids gasificationat their Vancouver testing facility. Nexterra is partnering with General Electric (GE) fordeveloping the gas cleaning technologies to support running Jenbacher engines on syngas. Thesyngas cleaning technology still requires further development before being widely practicedcommercially. At this time, syngas cleaning is considered to be in the emerging stage ofdevelopment and Nexterra is not actively marketing this technology in the biosolids market.

There are several other vendors that are also working to commercialize two stage gasificationtechnologies and bench and pilot scale studies are being conducted to continue thedevelopment.


Page 22 of 36

Figure 3-2. Two Stage Gasification System for Energy Recovery

From an energy and mass balance stand point, one can expect to obtain ~ 1 Mega Wattequivalent (MWe) of electricity from 25 dry tons per day (dtpd) dried and undigested biosolids(approximately 7,500 BTU/lb and ~ 70% VS content).

3.6.1 Ascent BioEnergy

Ascent offers biomass digestion and gasification technologies. It is unknown if AscentBioEnergy has any experience with sewage sludge since the vendor has not responded to theRFI at the time of writing this report.

3.6.2 Carbon BioEngineers Inc.

The Thermal Conversion of Organic Material (TCOM) system provided by Carbon BioEngineersis a thermal conversion process that utilizes a combination of pyrolysis, gasification, andcarbonization to convert organic materials such as biosolids to renewable energy and usablebyproducts.

3.6.3 D4

D4 technology group offers a pyrolysis/gasification technology. The process generates syngaswhich is cleaned and burned in an internal combustion (IC) engine. The process uses a rotarykiln for the pyrolysis/gasification reaction. The vendor was not responsive during the RFIprocess.

3.6.4 HGE – Korea (a KBI Group) High Temperature Conversion of Waste (HTCW)

HGE in Korea is a KBI group that provides technologies allowing green energy production fromwaste materials. The company appears to promote German technologies developed by KBIWaste & Energy Solutions GmbH. The company markets gasification technologies, anaerobicdigestion technologies along with a combination of both. The gasification technology is knownas the HTCW solution and the anaerobic digestion technology is known as the InnovativeAnaerobic Treatment System (IATS) solution. HGE markets themselves as a solution providernot just an equipment supplier and claim they can find funding required to finance a project.


Page 23 of 36

3.6.5 Integrated Environmental Technologies LLC – S4 Energy Solution

S4 Energy Solutions offers a unique gasification system that is split into to two steps. The firststage gasification step or pre-gasification system is a fixed bed down draft gasifier. The secondstage gasification step involves using a plasma enhanced melter (PEM™) chamber. The hightemperature electrically conducting gasifier is reported to convert the slag or ash to valuablebyproducts. The vendor has not responded to the RFI.

3.6.6 Intellergy

Intellergy offers a patented gasification and steam reforming process to convert dewateredbiosolids to renewable energy. The process uses a rotary gasifier to produce syngas that canbe further refined in the proprietary steam reforming process to generate H2 that can be used infuel cells. The syngas can also be refined to produce a liquid hydrocarbon fuel.

3.6.7 Kopf

The gasification system offered by Kopf, located in Sulz, Germany, is a fluidized bed updraftgasification system. The gasification system can be configured into either the close coupled ortwo stage gasification arrangement. Kopf does not currently have a North American businessarm or business partner so the feasibility of them supporting a North American project isquestionable.

3.6.8 Kore Process (G2E! Green Earth Energy)

The Kore process is a process that uses enhanced dewatering, drying and pyrolysis to generatepyrolysis gas which is ultimately converted to biodiesel. The process is still currently beingdeveloped and tested so the vendor is reluctant to provide extensive details of sludge to fuelprocess. The enhanced dewatering process used is the HydroCell dewatering process. Thesolution provider intends to own and operate the system and recuperate their costs through thesale of the diesel fuel and through tipping fees.

3.6.9 Nexterra

Nexterra in Kamloops, BC offers a fixed-bed, updraft gasification system. Nexterra can offergasification systems in both the two stage (with syngas cleaning) and close coupled (withoutsyngas cleaning) heat recovery configurations. Nexterra prefers to only offer their gasificationsystem, energy recovery and flue gas/syngas cleaning system and typically does not prefer toinclude a dryer in their scope. Nexterra has stated their preferred size range is at least 25 dtpd.

3.7 Alternative Combustion3.7.1 Fabgroups Technologies – Plasma Assisted Sludge Oxidation (PASO)

Fabgroups Technology out of Quebec offers a PASO system as a method to treat organicwastes and recover green energy. The PASO system is basically a rotary oven that contains aplasma torch. The vendor claims that the plasma torch, essentially acts as a catalyst tomaintain the exothermic oxidation reaction by lowering the activation energy required to start thereaction. The claim is reported as a benefit as the resulting ash does not get exposed toexcessively high temperature that could produce slag and clinkers but instead produces agranular ash product. They also claim to require little excess oxygen (~ 5% excess).

3.7.2 Kunmin

Kunmin E&C offers a different and unique process for drying sewage sludge. In the Kunminsystem, the biosolids are mixed with oil and sent to a vacuum evaporator. Kunmin claims thatthe thermal energy requirement is about 880 BTU/lb water (H2O) evaporated, which is


Page 24 of 36

significantly less than most thermal dryers that generally consume 1,400 – 1,550 BTU/lb H2Oevaporated.

3.8 Alternative “Smokeless” Sludge Oxidation3.8.1 ATHOS Wet Air Oxidation (WAO)

The ATHOS WAO process consists of oxidizing soluble or suspended components in waterusing oxygen as the oxidizing agent. When air is used as the source of oxygen, the process isreferred to as WAO. WAO is used to reduce the volume of sludge. Kruger/Veolia has notactively marketed the ATHOS process in North America during recent years.

3.8.2 Sci-Fi SuperCritical Water Oxidation (SCWO) – AquaCritox™

The SCWO process developed by Sci-Fi (AquaCritox®) is designed to convert thickened ordewatered residuals, at 6 - 18 % total solids (TS) content (by weight), to inert products bymeans of a complete oxidation reaction. SCWO uses supercritical water as the medium foroxidation. Supercritical water exists at temperatures and pressures greater than the criticalpoint of pure water, which is 705°F and 3,204 psi.

3.9 Fuel Production3.9.1 Enertech SlurryCarb™

The SlurryCarb™ process is based on the carbonization concept and involves exposing thebiosolids to elevated temperatures (450-600oF ) and pressures (800-1,800 pounds per squareinch gauge [psig]) for a defined period of time, followed by cooling, depressurization, dewateringand, if desired, drying and pelletization of the product solids. The vendor did not respond to theRFI.

3.9.2 N-Viro International

An N-Viro Fuel facility is typically a third party site that trucks in dewatered cake from WWTPs.The dewatered cake is mixed with an alkaline mixture (e.g. fly ash, cement kiln dust, lime kilndust, or lime). The mixed material (at 30 – 35% TS content by weight) is then sent to a dryer toevaporate water. N-Viro then markets the dry product as a coal substitute.

3.9.3 Panatech

Tsukishima Kikai (TSK) out of Japan has developed a drying and low temperature carbonizationtechnology to convert sewage sludge into a coal substitute. Panatech Inc. provided theinformation to AECOM. The claim is that the low temperature carbonization step will removeodors from the sewage sludge while maintaining the desired heating value of the material.

3.10 Other Solids Technologies3.10.1 Astec Thermal Remediation

Astec offers a soil remediation technology that they claim is also applicable to processingsewage sludge. The vendor has not provided any specific details at the time of writing thisreport for comparison. It appears that they are more geared towards offering a temporarysolution as opposed to a long term solution.

3.10.2 BioRenewables – Applied Filter Technologies

BioRenewables is a system integrator for anaerobic digestion and CHP systems. They appearto represent the Applied Filter Technology digester gas cleaning system. BioRenewables has


Page 25 of 36

proposed offering a digestion system with gas cleaning and a CHP system to CCH at no upfrontcapital cost.

The purpose of this report was to identify potential processing technologies and not evaluatefinancing, design build, or third party contracting options. The technology proposed byBioRenewables is an established biosolids technology. If anaerobic digestion with CHP ischosen as a favorable technology to consider, BioRenewables may offer an alternative projectand financing approach.

3.10.3 HydroCell Dewatering

HydroCell offers an enhanced dewatering process that can be placed upstream of gasification,pyrolysis or combustion processes. The vendor claims that through the addition of catalyst andseveral processing steps, the production of 60 - 75% DS is possible without requiring thethermal energy input required for evaporation. Enhanced dewatering processes are discussedin more detail in the Supplemental Report for Resolution 11-182: Alternative Technologies forthe Treatment and Minimization of Sewage Sludge.

3.10.4 Ledcor

Ledcor is a system integrator and solution provider for WWTPs. Ledcor, however, does notoffer their own proprietary processes and appears to package and integrate processes andtechnologies offered by other manufacturers. The company appears to favor the Cambi™ THprocess and Monsal™ enzymatic hydrolysis process. Ledcor also favors an enhanced primaryclarification technology. This report was focused on evaluating potential technology solutionsnot design build or financing options so this company was not evaluated further in this study.

3.10.5 PyroBioMethane™

The PyroBioMethane™ process is a pyrolysis technology currently under development. Unlikeother thermal destruction technologies, the PyroBioMethane process is intended to be used inconjunction with anaerobic digestion. The goal of the process is to produce a bio-oil that can bereturned to the digester using the theory that the bio-oil is readily digestible.

3.11 Non-Solids Technologies3.11.1 Beneficial Active Microorganisms (BAM)

The BAM technology consists of adding microbes to raw wastewater or septic tanks to minimizeodor and corrosion. This is not directly applicable to biosolids processing so no further contactwas made with regards to this report.

3.11.2 BioCleaner

BioCleaner Inc. is a bioremediation specialist that offers a biological process for which theyclaim produces no sludge for disposal. The BioCleaner process consists of using aeratorsalong with special microbes which they claim will treat and purify water without producing sludgefor disposition. The vendor claims that this process can be used on sludge streams rangingfrom 1% - 25% DS. The main market for this technology appears to be retrofits in existingaeration and settling basins.

3.11.3 ECO-H2O

ECO-H2O promotes micro and nano filtration for tertiary treatment. This vendor was notcontacted further since it is not applicable to processing biosolids or handling dewatered sludge.


Page 26 of 36

3.11.4 Global Environmental Technology Services (GETS)

GETS offers a system that they claim can replace traditional secondary and tertiary treatmentprocesses. The system utilizes a combination of sonic and adsorption processes to treatwastewater. The supplier claims that the sonic system creates aggressive micro-cavitationsthat rupture cell walls and destroy bacterial DNA. The vendor also claims that their system doesnot require the consumption of chemicals or use of filters for processing. In essence their claimis the treatment relies on physics, not chemistry or biology. This is not directly applicable tobiosolids processing so it will not be considered further in the evaluation.

3.11.5 SunPower

Most of SunPower’s experience appears to be with Solar Panels, although they do have oneproject where they are processing biosolids using anaerobic digestion at Ohio State University.The company appears to be proposing a system integrator for anaerobic digestion and CHPsystems.

3.12 Unknown Technologies3.12.1 Ebara

The vendor declined to respond to the RFI do to limitations in current staffing.

3.12.2 Waste to Energy

Waste to Energy has reportedly supplied and installed a biosolids gasification system in the UK,however, they declined to offer information since they do not offer technology as an open bid.Waste to Energy only works through special purpose vehicle (SPV) companies.


Page 27 of 36

4.0 EVALUATION CRITERIA

4.1 Intent of the ResolutionAs stated in the Resolution, this report “investigate[s] alternative technologies for the beneficialreuse of sewage sludge other than the technology used at the Sand Island WWTP’sbioconversion facility that will be sustainable and less harmful to the environment, includingtechnologies successfully used in Europe, Asia and North America by companies with goodreputations for credibility.” As such, only technologies other than anaerobic digestion, dryingonly, and pelletization are considered for beneficial reuse.

4.2 Onsite vs. Offsite TechnologiesThe beneficial reuse technologies considered are focused on the onsite treatment of solids atthe larger facilities (Honouliuli, Kailua, and Sand Island WWTPs). Although composting isconsidered a beneficial reuse, the product may be considered a soil amendment or fertilizer andthe Resolution states that “uses of sewage sludge byproducts for purposes other than fertilizershould be explored.” The offsite incineration at H-power may be beneficial; however, the energyproduced would not stay at the WWTP. Therefore, offsite technologies including composting byHER and incineration at H-Power are considered in the Supplemental Report for Resolution 11-182: Alternative Technologies for the Treatment and Minimization of Sewage Sludge.

4.3 List of CriteriaThe list of criteria used to evaluate and compare the various technologies and vendors include:

Is It a Solids Handling Process? Process Input Requirement Responded to RFI? Status of Technology Development Ease of Operation (This criterion is to indicate the staffing and skill set needs.) Regulatory and Permitting Impact Footprint Ability and Willingness of Vendor to Pilot Is Anaerobic Digestion Required/Desired for processing or energy production? End Product Ability to Produce Electricity Beneficial Byproducts Other Materials That Can Be Accepted (This criterion shows additional material that can

be processed by the technology.) Is Existing Or Different Drying Required? (This criterion shows what type of drying is

required and if the currently installed rotary drum dryer at the Synagro BioconversionFacility could be used with the newly proposed process.)

Consumables (This criterion shows what additional inputs are required for the process.) Capital Cost for 25 dtpd Facility (Vendor Provided) O&M Cost (Vendor Provided) Provided Costs Include Upstream Processing Such As Drying? (This criterion tries to

decipher what is included in the costs provided by the vendor.)


Page 28 of 36

It should be noted that capital and O&M costs presented are unverified vendor estimates andmay not include or take into account site requirements, ancillary items, and cost of installation inHawai‘i. In addition, some of the vendors do not have full scale installations.

4.4 “Fatal Flaw”In order to further consider appropriate technologies for sludge processing on the island ofOahu, technologies with one or more of the listed “fatal flaws” below are not consideredappropriate for Oahu’s future sludge processing. The technologies screened out in the processare listed below the bullet point.

Technologies that are not considered “solids processing based”a. Global Environmental Technologiesb. BioCleanerc. BAMd. ECO-H2O

Technologies unable to process the 25 dtpd minimum amount of sludge (This “fatal flaw”did not screen out any technologies.)

Technologies where the main product is material that requires land applicationa. Conventional Anaerobic Digestionb. Compostingc. Heat Dryingd. VitAge. VERTADf. Solorganicsg. BioZymeh. THi. Ledcorj. BioRenewablesk. SunPower

Technologies that are currently at the conceptual levela. Nexterra – Two Stageb. Intellergyc. BioPyroMethaned. Integrated Environmental Technologies

Technologies where the vendor actively declined to respond to the RFIa. Waste To Energyb. Ebara

Technologies where the providing vendor didn’t acknowledge or respond to the RFIa. Enertech Slurry Carbb. D4c. Ascent BioEnergy

Table 4-1 shows the list of technologies identified; the highlighted technologies are those thatare considered appropriate for processing sludge from the WWTPs. It should be noted thatdifferent screening criteria and other factors could impact technologies that could be consideredfurther. For example, Intellergy is still considered a concept technology since it has not beentested for biosolids, however, the process may offer significant benefits to CCH if the claims areproven in the San Francisco Bay Area demonstration plant. After some operation time of thedemonstration plant, this technology will move up to be the emerging technology classificationand CCH may want to consider this technology if results look positive. Based on this knowledge


Page 29 of 36

it may be desired to carry the technology to a further evaluation to see if it could be feasiblebased on economics and sustainability when compared to other technologies. Kopf, on theother hand, was screened for further evaluation based on the set criteria, however, they do nothave North American representation and supporting a project may be difficult. The lack of “localsupport” could also be considered a “fatal flaw” and may be a reason to screen this process out.

Further evaluation of the technologies should be qualitatively conducted using the criteria listedbelow in order to arrive at a group of technologies that are most appropriate for sludgeprocessing.

Expected capital cost Expected O&M cost Ease of operation and maintenance Energy producing potential Sustainable technology (measured as CO2e potential) Public perception of the facility

Although some of the information above is presented in the current comparison tables, a moredetailed evaluation and check should be performed to ensure that comparable scope items areincluded in the capital and O&M costs and that the “cost” factors are the same for both. Forexample, Nexterra provided a capital and O&M cost for their gasification systems but did notinclude the drying component as a part of the cost. In addition, the scope boundary for an O&Mestimate should be thoroughly checked in the detailed evaluation to ensure that any comparisonmade for further screening is based on an “apples to apples” comparison. For example theinclusion of any boundaries set for labor and hauling costs should be the same for all screenedtechnologies. This type of thorough check has not been completed at this time for this report butwill be performed in detail during the island wide study for the short listed technologies.

4.5 Technology Development Status and PilotingThe list and development status of technologies/vendors will be updated during the masterplanning process. “Concept” technologies are not considered for further evaluation unlesspiloting or a new installation causes the technology to be reclassified as an “emerging” or“demonstration” technology. A vendor could conduct pilot testing at one the WWTPs at noexpense to CCH. Pilot testing will not guarantee that the technology would be chosen;however, successful results will move the technology status from “concept” to “emerging.”

When conducting pilot studies there are logistics that CCH must consider with the set-up andfacilitation of one or more technology vendors including:

Space limitations at the WWTPs. Limited in-house resources to deal with pilot testing. Semi-permanent construction is required for such things as power supply, drainage

piping, process piping, washdown water, truck access, and equipment pads. If multiplepilot plants are tested on an ongoing basis these ancillary construction costs may be theresponsibility of CCH to ensure consistent testing parameters.

Size of the pilot installation has to be sufficient to demonstrate scalability to full operatingcapacity.

Some pilot testing may require building or air permits for construction or operation, whichmay delay the timeline for installation.


Page 30 of 36

Costs CCH will incur to have independent third party sampling and testing to ensure theproper operating conditions and test results are applicable to full scale installation andare done without preferential bias.

Pilot testing will operate intermittently during the startup and testing. There will beextended periods of no operation during adjustments to the pilot facility. When inoperation, the pilot facility will operate across a wide range of flows and operatingconditions in order to demonstrate capabilities.

In addition, the WWTPs must stay in compliance with permits at all times; so the CCH has lowtolerance for any activity that could be a potential risk to CCH. ENV must consider the benefitsthat could be obtained by pilot testing and how it is beneficial to CCH before allowingcommitment of CCH resources to these activities.

4.6 Risks of Unknown TechnologiesAs many of the technologies considered are not “established” and there are limited installationsworldwide, the risks of the unknown is high. There may be unknown disadvantages andunknown costs for the newer technologies. For “concept” technologies, the unknowns includelimited results of a pilot test and unforeseen costs which make it difficult to prove the claims ofthe vendor. For “emerging” technologies, there is the unknown of upsizing to a full scaleinstallation for both performance and costs. For “demonstration” technologies, the unknown iswhether the results from the full scale installation can be reproduced at another WWTP withdifferent sludge characteristics


Page 31 of 36

Table 4-1. Technology Comparison


Page 32 of 36

Insert Page 2 of Table


Page 33 of 36

5.0 TECHNOLOGIES FOR FUTURE CONSIDERATIONBased on the “fatal flaw” screening criteria, the following list of appropriate technologyclassification and vendors were identified as “appropriate technologies” to consider in the islandwide study:

Incineration Gasification and Pyrolysis (Closed Coupled)o Kruger BioCon + ERSo MaxWesto Nexterrao Prime Energy Gasificationo Pyrobuster

Gasification and Pyrolysis (Two Stage)o Carbon BioEngineers Inc.o HGE – Korea (a KBI Group) HTCWo Kopfo Kore process (G2E!)

Alternative Combustiono Fabgroups Technologies – PASOo Kunmin

Alternative “Smokeless” Sludge Oxidationo ATHOS WAOo Sci-Fi SCWO – AquaCritox™

Fuel Productiono N-Viro Internationalo Panatech

Other Solids Technologieso Astec Thermal Remediationo HydroCell Dewatering


Page 34 of 36

6.0 SELECTION AND IMPLEMENTATION

6.1 Supplemental Report for Resolution 11-182: Alternative Technologies for theTreatment and Minimization of Sewage Sludge

In addition to this document, the Supplemental Report for Resolution 11-182: AlternativeTechnologies for the Treatment and Minimization of Sewage Sludge will be completed toidentify other solids technologies that may be appropriate for solids treatment but may notaddress the Resolution. These technologies may be applicable to both the small and largeWWTPs. Similar to this report, the Supplemental Report for Resolution 11-182: AlternativeTechnologies for the Treatment and Minimization of Sewage Sludge will list technologies toconsider for further evaluation during the master planning process.

6.2 Island-wide Solids Master PlanCCH is currently beginning an Island-wide Solids Master Plan to evaluate the existing solidstreatment and disposal at all the CCH operated WWTPs and to recommend any improvementsor upgrades at these WWTPs. The solids recommendations from the Honouliuli, Kailua, andSand Island, and Waianae Facilities Plans will be incorporated into the Island-wide SolidsMaster Plan.

It should be noted that many criteria must be considered in the course of making decisions onprocesses, technologies, and improvements. The criteria may include, but not be limited to,constraints due to permits, required approvals, future regulations, sustainability, cost-efficiency,security, solid waste management, energy management, land availability, back-up systems,maintaining acceptable levels of risk, and emergency preparedness. The issues involve morethan just wastewater management, but include consideration of City-wide policies and long-range planning. An important step along with the master planning work will be development ofthe decision criteria to use, and the relative priority of the many criteria to consider.

6.2.1 Island-wide Solids Quantity and Quality

One part of the Island-wide Solids Master Plan is to determine existing and to project futuresolids quantity and quality at each WWTP. The projection will consider projected developmentsin the WWTP sewer basin. In addition, planned WWTP upgrades and their effects on quantityand quality will be considered. The results of this task will be provided in an Island-wide SolidsQuantity and Quality Technical Memorandum.

6.2.2 Solids Reduction at Smaller WWTPs (< 5 mgd)

The intent of this task is to determine the cost effectiveness of onsite biological biosolidsreduction treatment to reduce hauling, offsite treatment, and/or disposal costs for the smallerWWTPs, especially the WWTPs that haul liquid waste to the larger facilities. The technologiesrecommended for further evaluation in the Supplemental Report for Resolution 11-182:Alternative Technologies for the Treatment and Minimization of Sewage Sludge will be reviewedto determine technologies that may be applicable at the smaller WWTPs. The recommendationat each WWTP may vary depending on the space available onsite and the quantity of liquidwaste hauled. The results of this task will be provided in a Solids Reduction at Smaller WWTPsTechnical Memorandum.

6.2.3 Island-wide Transportation, Treatment, and Disposal

This task evaluates the cost effectiveness of transportation, treatment, and disposal options forall nine CCH operated WWTPs. Items considered include hauling from the smaller WWTPs tothe regional facilities to be processed and hauling biosolids to a central facility for disposal or


Page 35 of 36

hauling from all WWTPs to a centralized facility to be processed and disposed. Thetechnologies recommended for further evaluation in this document will be reviewed to determinethe technologies that may be applicable at Honouliuli, Kailua, and/or Sand Island WWTP. Theresults of this task will be provided in an Island-wide Transportation, Treatment, and DisposalTechnical Memorandum.

6.2.4 Redundancy and Reliability for Processing and Disposal

The intent of this task is to determine the reliability and back-up options for the planned solidsprocessing and disposal in the event that one option is unavailable due to mechanical failure orother cause. Also included is the ability of various technologies to receive solids diverted fromother WWTPs. The results of this task will be provided in a Reliability and Redundancy forSolids Processing and Disposal Technical Memorandum.

6.2.5 Island-wide Solids Processing and Disposal Plan

The Island-wide Solids Processing and Disposal Plan will incorporate the findings of theprevious reports to recommend upgrades to the existing solids processing and disposal at eachWWTP. The Island-wide Solids Processing and Disposal Plan will also include a schedule forthe island-wide plan which considers construction and phasing of the projects.

6.3 Life-Cycle Cost AnalysisLife-cycle cost analysis will be conducted as part of the Island-wide Solids Master Plan. Thelimits for the life-cycle cost analysis must be the same for the various alternatives for an equalcomparison. Included in the life-cycle cost analysis are the capital costs and the O&M costs.

It should be noted that some solution providers responding to the RFI were not actuallyequipment manufacturers or suppliers. These solution providers were often system integratorsthat provide an alternative means of financing, often involving a rate payback system or powerpurchase agreement to recuperate initial construction costs.

In addition, some vendors claim that their technology is “free.” CCH must consider what “free”means which includes:

Does it mean that CCH would not need to pay any upfront capital costs? How much willit cost CCH compared to paying the capital cost since the vendor is likely to include acontingency and profit in the annual cost?

Is all equipment included or is just one piece of equipment free? Are other ancillaryitems included and how much is the cost of the additional equipment?

What is the end product produced and does the vendor take responsibility for finaldisposal?

If there is a process upset, process does not work, or if the disposal outlet is notviable/available will they take on the responsibility and cost for alternative means ofdisposal?

The life-cycle cost of “free” must be taken into consideration if evaluating these “solutionproviders.”


Page 36 of 36

6.4 Schedule and Implementation6.4.1 Pilot Testing

If conducted, pilot testing of technologies is anticipated to take at least 18 to 24 months. Thisincludes 12 months of data collection once the pilot testing facility is in operation.

6.4.2 Master Plan Timeline

The master plan timeline is as follows:

Biosolids Sampling Plan (submitted August 2011) Complete Sampling and Testing - January 2012 Island-wide Solids Quantity and Quality Estimates – April 2012 Solids Reduction at Smaller WWTPs – May 2012 Island-wide Transportation, Treatment, and Disposal – May 2012 Redundancy and Reliability for Processing and Disposal – August 2012 Island-wide Solids Processing and Disposal Plan – December 2012

6.4.3 Design and Construction

Design and construction scheduling depends on the construction and phasingrecommendations in the Island-wide Solids Processing and Disposal Plan. It is anticipated thatdesign for each project would take one year and procurement and construction would take twoto three years. It is assumed that some projects may run concurrently.

6.4.4 Honouliuli and Sand Island Secondary Treatment

The Honouliuli and Sand Island WWTPs are anticipated to begin full secondary treatment by2024 and 2035, respectively, in accordance with the 2010 Consent Decree. The solids quantityis expected to increase substantially when these WWTPs become secondary WWTPs. Masterplanning efforts along with any near term design and construction will take into consideration thetiming and future anticipated needs at both facilities.

6.4.5 Facilities Planning for Kailua, Honouliuli, Sand Island, and Waianae WWTPs

Currently, CCH is in the process of developing Facilities Plans for Kailua, Honouliuli, SandIsland, and Waianae WWTPs. As part of the facility planning process, the consultant wouldevaluate the existing WWTP. Although the timeframe for completion of these Facilities Plansare unknown; AECOM will work with the consultants so that the net outcome of Facilities Plansand Island-wide Solids Master Plan will be coordinated to be in agreement regarding theproposed solids handling facilities at the referenced WWTPs.

Appendices

Appendix A – Resolution 11-182

CITY COUNCILCITY AND COUNTY OF HONOLULU No 11—182

HONOLULU, HAWAII

RESOLUTION

URGING THE CITY ADMINISTRATION TO INVESTIGATE ALTERNATIVETECHNOLOGIES FOR THE BENEFICIAL REUSE OF SEWAGE SLUDGE OTHERTHAN THE REUSE TECHNOLOGY CURRENTLY BEING USED AT THE SANDISLAND WASTEWATER TREATMENT PLANT.

WHEREAS, the City is currently reusing sewage sludge at its Sand Islandwastewater treatment plant (WV\JTP) by using an in-vessel bioconversion facility,(“bioconversion facility”) operated by Synagro to convert the sludge, also known asbiosolids, to fertilizer pellets; and

WHEREAS, the beneficial reuse of sludge at the Sand Island WWTP wasrequired as part of a 1995 consent decree and therefore, funding for the bioconversionfacility was approved by the City Council in 2004 despite opposition from neighborhoodboards, business groups and the affected community; and

WHEREAS, concerns about the bioconversion facility include the following:

(1) Public health and safety. Research by David Lewis, a microbiologist,found that the treatment process used in the beneficial reuse of sludgedoes not kill all pathogens in the sludge. Because the fertilizer pelletsproduced at the Synagro bioconversion facility are being used at Cityparks, playgrounds and golf courses, there is a concern about the public’shealth and safety due to pathogen re-growth. In a 2009 study, anationwide survey of sewage treatment plants found that the sludgeproduced at those plants contained a wide variety of toxic metals,pharmaceuticals, flame retardants and other compounds, including someantibiotics in surprisingly high concentrations, and the U.S. EnvironmentalProtection Agency is continuing to assess the health risks posed by thesechemicals.

(2) Impacts to businesses and residents. On Sand Island, there are 110lessees on State land who borrowed money to establish and grow theirbusinesses and to build infrastructure serving their leased land who havebeen severely affected by the bioconversion facility. Further, in 2003, aconsultant to Synagro determined that there was sufficient land at theSand Island WWTP to build additional bioconversion facilities on SandIsland that could handle not only sludge from that plant but from other Citywastewater treatment plants. Therefore, the construction of additionalbioconversion facilities could mean that trucks carrying sludge will pass byresidences and businesses before arriving at the Sand Island WWTP.

OCS/062111/08: 07/CT 1

CITY COUNCILCITY AND COUNTY OF HONOLULU No 11 —1 82

HONOLULU, HAWAII

RESOLUTION

(3) Visual blight and impacts to tourism. The current bioconversion facility isabout 116 feet tall, almost double the allowed 60-foot height limit in theSand Island area. The massive structures in the complex that make upthe facility can be seen not only by Kalihi residents and downtownbusinesses but also by tourists who arrive and depart at HonoluluInternational Airport. Addition of a second bioconversion facility, and theadministration’s plan to build even more bioconversion facilities at theSand Island WWTP, will add to this visual blight and may negatively affectthe state’s number one industry.

(4) Marketability of fertilizer pellets. The City entered into a contract withSynagro to operate the bioconversion facility and market the fertilizerpellets produced at that facility. Under the contract, Synagro wouldproduce 6,000 tons of fertilizer pellets per year, of which 2,000 tons wouldbe for the City for use at its parks and golf courses, and the remaining4,000 tons would be marketed by Synagro. In a 2009 annual report bySynagro on the beneficial reuse of the sludge, it was reported that only3,415.54 dry tons of pellets were produced, of which only 1,292.28 drytons were marketed. When factoring in labor and transportation costs, themarketing of the pellets resulted in a net loss of $63,447.82 in Fiscal Year2009. In calendar year 2010, the total revenue generated from the sale ofthe fertilizer pellets was only $438, and when the cost of labor andtransportation was considered, the marketing of the pellets resulted in anet loss of $124,343.

(5) Reputation and credibility. Serious issues have been raised regarding thereputation and credibility of the current operator of the bioconversionfacility.

(6) The cost to construct the existing bioconversion facility was over $40million, including cost overruns exceeding $7 million, and the projectedcost of the second facility was budgeted at $26 million;

and

WHEREAS, based on the above-enumerated concerns, the Council deleted $26million in funding from the fiscal year 2012 executive capital budget for a secondbioconversion facility at the Sand Island WWTP; and

2


HONOLULU, HAWAII

RESOLUTION

WHEREAS, despite the concerns regarding the treatment of sludge using thebioconversion facility, the Council recognizes the need to treat wastewater sludge sothat it can be beneficially reused rather than being disposed of at the City’s landfill; and

WHEREAS, there are a number of reputable companies employing alternativetechnologies in Europe, Asia and North America that appear to pose fewer risks topublic health and safety than the Synagro technology for the beneficial reuse of sewagesludge; and

WHEREAS, uses of sewage sludge byproducts for purposes other than fertilizershould be explored, including use as fuel; now, therefore,

BE IT RESOLVED by the Council of the City and County of Honolulu that the Cityadministration is urged to investigate alternative technologies for the beneficial reuse ofsewage sludge other than the technology used at the Sand Island VVVVTP’sbioconversion facility that will be sustainable and less harmful to the environment,including technologies successfully used in Europe, Asia and North America bycompanies with good reputations for credibility; and

BE IT FURTHER RESOLVED that the City administration is requested to reportback to the Council within 90 days of the adoption of this Resolution regarding itsinvestigation of alternative technologies; and

BE IT FURTHER RESOLVED that the City administration is requested to providethe Council with copies of any documents or other forms of information theadministration has obtained regarding alternative technologies for the beneficial reuseof sewage sludge; and

BE IT FURTHER RESOLVED that it is the intent of the Council to work with theCity administration expeditiously to implement a safe and healthful alternative to theSynagro technology so as to ensure that any necessary construction may commence assoon as possible; and

3


HONOLULU, HAWAII

RESOLUTION

BE IT FINALLY RESOLVED that copies of this Resolution be transmitted to theMayor, the Managing Director, the Director of the Department of EnvironmentalServices, and the Sand Island Business Association.

INTRODUCED BY:

DATE OF INTRODUCTION:

JUN 28 2011 _____________Honolulu, Hawaii Councilmembers

4

CITY COUNCILcii~AND COUNTY OF HONOLULU

HONOLULU, HAWAIICERTIFICATE

RESOLUTION 11-182

Introduced: 06/28/Il By: ROMY CACHOLA Committee: COUNCIL

Title RESOLUTION URGING THE CITY ADMINISTRATION TO INVESTIGATE ALTERNATIVE TECHNOLOGIES

FOR THE BENEFICIAL REUSE OF SEWAGE SLUDGE OTHER THAN THE REUSE TECHNOLOGY

CURRENTLY BEING USED AT THE SAND ISLAND WASTEWATER TREATMENT PLANT.

Links~RESi.i1~82.~ -

Voting Legend: Y= Aye, Y~= Aye w/Reservations, N = No, A = Absent, ABN = Abstain

CC-i 85 CHANG — REFERRAL OF RESOLUTION 11 -182 TO COUNCIL FLOOR.

COUNCIL 07/06/11 RESOLUTION 11-182 WAS ADOPTED.

ANDERSON Y BERG Y CACHOLA Y CHANG Y GABBARD Y

GARCIA Y HAR IMOTO Y KOBAYASHI Y MARTIN Y

I hereby certify that the above is a true record of action by the Council of the City and

BERNICE K. N. MAU, CITY CLERK

ION.

Appendix B – RFI

mayor's message 152

News & Politics

alternative technologies

solids technologies

unknown technologies

solids treatment

alternative combustion

sewage sludge incineration

bishop street

aecom report