11

March 3rd, 2011March 3rd, 2011

Industry Update on Nitrogen RemovalIndustry Update on Nitrogen RemovalPrograms Across the United States:Programs Across the United States:What Does it Mean for New England?What Does it Mean for New England?

Richard H. CisternaRichard H. Cisterna, P.E, P.E..

22

Nitrogen Treatment Technology Overview

Water Industry Sustainability11

22

33

44

OOutlineutline

Conventional and AdvancedCase Studies

55

National Perspective - Nitrogen and Hypoxia

Massachusetts Estuaries

66 Summary and Conclusions

33

Water Industry SustainabilityWater Industry Sustainability

44

Sustainability is inSustainability is in VogueVogue

55

Focus of Sustainability has been on EnergyFocus of Sustainability has been on Energy

● Energy Audits

● Energy Optimization

● Renewable EnergySources

66

Sustainability BalancingSustainability Balancing ActAct

Water SupplyWater Supply //Wastewater EffluentWastewater Effluent

GreenGreen EnergyEnergyCarbon FootprintCarbon Footprint

Nitrogen

77

National Perspective onNational Perspective on

Nitrogen and HypoxiaNitrogen and Hypoxia

88

Nitrogen is an Emerging National ConcernNitrogen is an Emerging National Concern

99

Nitrogen’s Impact on the EcosystemNitrogen’s Impact on the Ecosystem

Source: evworld.com

1010

Chesapeake Bay Oxygen DepletionChesapeake Bay Oxygen Depletion

Source: evworld.com

1111

Long Island Sound Nitrogen Control Program

● In 1998, CT, NY, and EPA agreed to reducehuman sources of N by 58.5% by 2014. ATMDL was developed and approved by EPAin 2001.

1212

Long Island SoundLong Island Sound

Source: CTDEP and Long Island Sound Study

1313

The Mississippi River Carries A lot of NitrogenThe Mississippi River Carries A lot of Nitrogen

1414

And the Gulf of Mexico Pays the Price…And the Gulf of Mexico Pays the Price…

Source: evworld.com

1515

Historical Development of Nitrogen LimitsHistorical Development of Nitrogen Limits

1990 20202000 2010

10

9

8

7

6

5

4

3

2

1

0

TMDL(mg/l)

North Carolina

Chesapeake Bay

Florida

Long Island Sound, CT

Long Island Sound, NYC8 mg/l

5 mg/l

3 mg/l

1.5 mg/l

1616

Massachusetts EstuariesMassachusetts Estuaries

1717

Mass Estuaries also have nitrogen concernsMass Estuaries also have nitrogen concerns

1818

Mass Nitrogen Reduction Program GoalsMass Nitrogen Reduction Program Goals

» Reduce ‘N’ to estuaries

» Consider centralized and decentralizedapproaches

» Highly treat wastewater to newMassachusetts DEP Standards

» Strategically recharge reclaimed water

1919

Western Cape Recharge BasinsWestern Cape Recharge Basins

Source: USGS

2020

Mass. DEP: Groundwater Discharge ProgramMass. DEP: Groundwater Discharge Program(314 CMR 5.00)(314 CMR 5.00)

RequirementsRequirements

All DischargesAll Discharges

Meet secondary treatment effluent limits:

» Nitrate as Nitrogen < 10 mg/L

» Total Nitrogen < 10 mg/L

» Fecal Coliform < 200 colonies per 100 mL

Discharges withinDischarges withinZone II or IWPAZone II or IWPA

Effluent shall be filtered to meet:

» TSS < 10 mg/L

» Turbidity < 5 NTU

» TOC < 3 mg/L

Discharges withinDischarges withinZone II or IWPAZone II or IWPAand 2 year Traveland 2 year TravelTimeTime

oror

Direct InjectionDirect Injection(into saturated(into saturatedzone)zone)

Effluent shall be oxidized, filtered, disinfected and coagulatedto meet:

» TSS < 5 mg/L

» Turbidity < 2 NTU

» BOD < 10 mg/L

» TOC < 1 mg/L

» Fecal Coliform = avg. of zero colonies per 100 mL over a

continuous 7 day sampling period; no single

sample shall exceed 14 colonies per 100 mL

» Virus = 5 Log Inactivation and/or Removal

Disinfection shall not be waived.

Coagulation may be waived if meet turbidity requirement withfiltration alone.

2121

Treatment Approaches?Treatment Approaches?

● Decentralized Advanced Septic Systems

● Biological Treatment

● Centralized MF/RO, (AOP?) – Concentrate Issue

● MF, GAC, (AOP?)

2222

Regulations for Indirect Potable ReuseRegulations for Indirect Potable Reuse

Florida Mass. California Arizona Australia

Nitrogen 10 ppm* 10 ppm* 5 ppm 10 ppm 1 ppm

TOC 3 ppm3 ppm1 ppm

0.5 ppm --- 1 ppm

EmergingContaminants

No/Yes No? Yes No/Yes Yes

* Local requirements can be more stringent

2323

Nitrogen TreatmentNitrogen Treatment

2424

Nitrification /Nitrification / DenitrificationDenitrification ActivatedActivatedSludgeSludge ProcessProcess -- MLEMLE

● Solids in primary sludge (5 - 10 %)● Biosynthesis in WAS (10 - 20 %)● Denitrification (40 - 60 %)

SecondaryClarifiers

PrimaryClarifiers

Air Blowers

Aeration Tanks

AerobicAnoxic

Return Sludge

SecondaryEffluent

Waste ActivatedSludge

PrimarySludge

PretreatedWastewater

N&P Removal

TKN = 30 mg/LTP = 7 mg/L

NH3-N < 2 mg/LNO3-N < 5 mg/LTN = 8 mg/LTP = 5 mg/L

TN ~ 8 to 10 mg/L

3Q

2525

BNR Step Feed ConfigurationBNR Step Feed Configuration

TWO-STEP FEED PROCESS

FOUR - STEP FEED PROCESS

SecondaryClarifiers

Anoxic AnoxicAerobic Aerobic

Step Feed

RAS

SecondaryEffluent

Waste ActivatedSludge

PretreatedWastewater

SecondaryClarifiers

AnoxicAnoxic AnoxicAnoxic AerobicAerobic AerobicAerobic

RAS

SecondaryEffluent

Waste ActivatedSludge

PretreatedWastewater

TN ~ 6 to 9 mg/L

TN ~ 4 to 6 mg/L

2626

SecondaryEffluentWastewater

WAS

BNRAeration Tank

SecondaryClarifier

PrimaryAnoxic

SecondaryAnoxic

Aerobic Re-aeration

Anaerobic

Typical 5-stage BNR Process – Lower TN limit

BNR Process ConfigurationsBNR Process Configurations –– 55--stagestage

Carbon

TN ~ 3 to 4 mg/L

2727

3+ Stage with Denitrification Filters3+ Stage with Denitrification Filters

SecondaryEffluentWastewater

WAS

MethanolAcetate

BNRAeration Tank

SecondaryClarifier

GranularMediaFilter

Anoxic AerobicAnaerobic

TN < 3 mg/L

2828

Denitrification FiltersDenitrification Filters

● Nitrified secondary effluent sent to filtration

● Filter media used to grow an attached biomass thatwill denitrify the secondary effluent

● Supplemental carbon addition

● Good solids removal + denite – 2 gpm/ft2

2929

Typical MBR Process

Membrane Bioreactor (MBR)Membrane Bioreactor (MBR)

3030

Integrated Fixed Film Activated SludgeIntegrated Fixed Film Activated Sludge(IFAS)(IFAS)

● Media held in Aeration Basins to provideattached growth for Nitrifying biomass

● Typical Floating and Fixed IFAS Media

» Kaldnes (plastic)

» Linpor (sponge)

» Ringlace (cord)

30

3131

IFAS in Nutrient RemovalIFAS in Nutrient Removal

ANA ANOX AEROBIC ANOX

•Higher capacity in samevolume•“Modular” phasing•Improved wet weatherstability

3232

TZ Osborne WRFTZ Osborne WRF –– Pilot LayoutPilot Layout

IFASCell 1

IFASCell 2

IFASCell 3

PrimaryEffluent

RASTo FinalClarifier No. 7

~ 35% fill (AK-K3)

3 distinct zones

Screens for each cell

Isolation / throttle airvalve for each cell

3333

IFAS Pilot Results / Lessons LearnedIFAS Pilot Results / Lessons Learned

● Effective nitrification inapproximately half theaerobic volume

● Dynamic microbialpopulation

● Higher air usage

● Screen headloss higher thanexpected

● Foam handling a must

● Influent screening must besized correctly (i.e. openingsize)

0

5

10

15

20

25

30

04/01/08 06/13/08 08/25/08 11/06/08 01/18/09 04/01/09

Bio

ma

ss

on

Me

dia

(gT

SS

/m2

of

me

dia

su

rfa

ce

)

Date

Cell D Biomass Cell E Biomass Cell F Biomass

3434

BioMagBioMag

From CWT Website -http://cambridgewatertech.com/technology/biomag

3535

Typical Process Treatment Train for UltraTypical Process Treatment Train for Ultra--LowLowNutrient StandardsNutrient Standards

3636

Cost vs. Nitrogen RemovalCost vs. Nitrogen Removal

Nitrogen Removal (mg/L)

Cost ($)

3737

Nitrogen Removal Option Summary*Nitrogen Removal Option Summary*

CriteriaCriteria22--StageStage

BNRBNR

4/54/5--StageStageBNRBNR

+ Carbon+ CarbonFeedFeed

4/54/5--StageStageBNRBNR

++ DeniteDeniteFiltersFilters

4/54/5--StageStageBNRBNR

+ MBR w/+ MBR w/CarbonCarbon FeedFeed

4/54/5--StageStageBNRBNR

+ UF + NF or+ UF + NF orRORO

TN effluentAchievable

8 - 12 mg/L 3 - 6 mg/L 3 - 4 mg/L 2 - 3 mg/L < 1.5 mg/L

Capital Costper GPD

$0.25 - $1.25 $0.50 - $2.00 $1.25 - $2.50 $2.50 - $3.00 $3.00 - $4.00

EnergyUsage perMGD

40 kW 50 kW 55 kW 100 kW 125 kW

Annual O&MCost perMGD

$21k - $28k $30k - $40k $35k - $47k $121k - $161k $261k - $348k

*Relative cost for additional treatment only. Total cost will depend on the available plant infrastructure.

3838

Supplemental CarbonSupplemental Carbon

3939

Available Supplemental Carbon SourcesAvailable Supplemental Carbon Sources

● Methanol

● Ethanol

● Acetic acid

● Corn syrup/sugar

● Glycerin

● MicroC™

● Primary fermentate

4040

Methanol ConsiderationsMethanol Considerations

● Benefits

» Low cost (relative to alternatives)

» Low yield (low solids production)

» Proven technology

● Drawbacks

» Requires specialist population

■ Slow growing

» Volatile price

» Slower kinetics

» Flammable

Recent Methanol Accident Site atBethune Point WWTP

4141

Methanol CostsMethanol Costs –– 2001 to 20092001 to 2009(Expect Price Fluctuations)(Expect Price Fluctuations)

$0.00

$0.50

$1.00

$1.50

$2.00

$2.50

$3.00

Ap

r-0

1

Oct-

01

Ap

r-0

2

Oct-

02

Ap

r-0

3

Oct-

03

Ap

r-0

4

Se

p-0

4

Ma

r-0

5

Se

p-0

5

Ma

r-0

6

Se

p-0

6

Ma

r-0

7

Se

p-0

7

Ma

r-0

8

Se

p-0

8

Ma

r-0

9

Me

tha

no

lP

ric

e($

/Ga

llo

n)

www.methanex.com

4242

GlycerinGlycerin

● Typically byproduct ofbiodiesel production

● Benefits

» Faster kinetics

» Specialist population notrequired

● Drawbacks

» Potential for productinconsistencies withwaste products

» Viscous in cold weather

● Products

» Brenntag

» Unicarb-DN

» BioCarb DN (Denite-1)

» MicroC-Glycerin

» Waste products

4343

Alternative Carbon TestingAlternative Carbon Testing

Parameter NRWWTP HCWRF PWWTP SDWRF NDWRF

Size (mgd) 75 75 7.5 20 20

Feed point Second anoxic zone

Basins fedcarbon

One All All One 4 out of 5

Control(ifapplicable)

One parallelbasin thatwas fed

methanol

Full-scaleevaluation,therefore no

control

Full-scaleevaluation,therefore no

control

One parallelbasin that

was not fedcarbon

One parallelbasin that

was not fedcarbon

Substrate Glycerin Sugar waterand glycerin

Glycerin Glycerin Glycerin

4444

Parkway WWTPParkway WWTP

INFLUENT PUMPSTATION

SECONDARYCLARIFIERS

MLR PUMPSTATION

BNR BASIN #2(RB2)

SOLIDS HANDLING

RASPUMPSTATION

PRIMARYCLARIFIERS

GRITREMOVAL

BNR BASIN #1(RB1)

CHLORINECONTACTBASINS

4545

Parkway FullParkway Full--Scale Pilot DataScale Pilot Data

Full Scale Pilot Data

0

1

2

3

4

5

6

10/2

7/2

007

11/3

/2007

11/1

0/2

007

11/1

7/2

007

11/2

4/2

007

12/1

/2007

12/8

/2007

12/1

5/2

007

12/2

2/2

007

12/2

9/2

007

1/5

/2008

1/1

2/2

008

1/1

9/2

008

1/2

6/2

008

Co

ncen

trati

on

(mg

/L)

0

20

40

60

80

100

120

Carb

on

do

se,g

al/d

ay

Effluent NOx Effluent TN Brenntag Glycerin 7 per. Mov. Avg. (Effluent NOx) 7 per. Mov. Avg. (Effluent TN)

■ No Acclimation Period Required

4646

BNR Tank 8

NRCY

NRCY

NRCY

NRCY

BNR Tank 7

BNR Tank 6

BNR Tank 5 ToSecondary

ClarifierNo. 8

ToSecondary

ClarifierNo. 7

3848-047

Cell1

RAS

RAS

RAS

RAS

RAS

RAS/WASPump Station

RA

SPip

eline

PE

Dis

trib

ution

Channel

ML

Dis

trib

ution

Channel

ML Distribution Channel

RA

S

Ferm

enta

tion

Anaero

bic

Zone

Prim

ary

Anoxic

/

Anaero

bic

Zone

Re-

Aera

tion

ZonePrimary

Anoxic/Aerobic Zone

SecondaryAnoxic/

Aerobic ZoneAerobic Zone

Cell 2 Cell 3Cell 5 Cell 8 Cell 11

Cell 4Cell 7 Cell 10 Cell 13Cell 6 Cell 9 Cell 12

Henrico VAHenrico VA

4747

Henrico County WRF Plant Effluent NitrogenHenrico County WRF Plant Effluent NitrogenProfile vs. Substrate Feed RateProfile vs. Substrate Feed Rate

● Sugar water and glycerin both effective.

4848

North Carolina “Conventional”North Carolina “Conventional”

Case StudiesCase Studies

4949

Neuse River WWTP, Raleigh, NCNeuse River WWTP, Raleigh, NC

● 60 mgd Advanced WWTP

» Primary Clarifiers

» 4-stage BNR w/ methanoladdition

» Denitrification Filters w/methanol addition

● Largest Plant in Eastern U.S.Achieving LOT for TN UtilizingConventional Suspended GrowthBNR Process

● Upcoming Expansion to 75 mgd

» TN = 2.7 mg/L, TP = 1 mg/L

● Calibrated BioWin Model Used to

Evaluate/ Optimize Expansion

5050

Typical Operating Parameters

Neuse RiverNeuse River ––44--stage w/stage w/ denitrificationdenitrification filtersfilters

5151

● Most TN Removal in BNR Basins

● Filters “Trimming” ± 1 mg/L (~ 5 mg/L Methanol Dose)

● Annual Average Effluent TN = 2.4 mg/L (2004 - 2008)

● 2007 Annual Average Effluent TN = 1.96 mg/L

Neuse RiverNeuse River -- Operation and PerformanceOperation and Performance

S E a n d F in a l E f f lu e n t N i t r o g e n C o n c e n t r a t io n s

0

1

2

3

4

5

6

Ja

n-0

4

Ma

r-0

4

Ma

y-0

4

Ju

l-0

4

Se

p-0

4

No

v-0

4

Ja

n-0

5

Ma

r-0

5

Ma

y-0

5

Ju

l-0

5

Se

p-0

5

No

v-0

5

Ja

n-0

6

Ma

r-0

6

Ma

y-0

6

Ju

l-0

6

Se

p-0

6

No

v-0

6

Ja

n-0

7

Ma

r-0

7

Ma

y-0

7

Ju

l-0

7

Se

p-0

7

Co

nce

ntr

ati

on

(mg

/L)

E F F T N S E T N 3 0 p e r . M o v . A v g . (E F F T N ) 3 0 p e r . M o v . A v g . ( S E T N )

5252

High Point, NCHigh Point, NC –– 2626 mgdmgd, 5, 5--stage processstage process

5353

High Point PerformanceHigh Point Performance

0

2

4

6

8

10

12

14

16

18

20

22

9/1

/200

2

11/3

0/2

00

2

2/2

8/2

003

5/2

9/2

003

8/2

7/2

003

11/2

5/2

00

3

2/2

3/2

004

5/2

3/2

004

8/2

1/2

004

11/1

9/2

00

4

2/1

7/2

005

5/1

8/2

005

8/1

6/2

005

11/1

4/2

00

5

2/1

2/2

006

5/1

3/2

006

8/1

1/2

006

11/9

/2006

2/7

/200

7

5/8

/200

7

8/6

/200

7

11/4

/2007

2/2

/200

8

5/2

/200

8

7/3

1/2

008

10/2

9/2

00

8

EF

FT

ota

lN

itro

gen

(mg

/L)

EFF TN 30 per. Mov. Avg. (EFF TN)

Average Eff TN 1/07 to 12/08 = 3.3 mg/L

Avg TP = 0.18 mg/L Biologically

No supplementalcarbon

No alum or ferric

5454

Major Recycle ImpactsMajor Recycle Impacts

● Solids handling recycle streams

» Filtrate, centrate, gravity thickeneroverflow

● Frequency of return

ParametersPlant Influent Loads

(lbs/day)Plant Recycle Loads

(lbs/day)

Contribution FromPlant Recycles

(%)

BOD 43,600 2,830 6.5

TSS 39,300 6,590 17

TKN 5,700 1,620 29

TP 1,280 680 53

5555

Florida “Advanced”Florida “Advanced”

Case StudiesCase Studies

5656

Florida vs. Mass Estuary Nitrogen ChallengeFlorida vs. Mass Estuary Nitrogen Challenge

● FL - Existing Ocean Outfalls and Septic Tanks

● Cape – Mostly Septic Tanks

● Both – High Level Nitrogen Treatment / Recharge

5757

Class IDeep Injection Wells

EffluentReuse

Two Key issues for FDEP:

● Alternate Water SupplyResource

● Environmentalenhancement (Nitrogen)

Historically, South Florida’s sole source supplyHistorically, South Florida’s sole source supply(the Biscayne Aquifer), was fiercely protected(the Biscayne Aquifer), was fiercely protected

5858

Existing Supply Limited for UtilitiesExisting Supply Limited for Utilities

C.E.R.P

No New Waterfor the Public

5959

Recent LegislationRecent Legislation –– Ocean Outfall BanOcean Outfall Ban

● Outfall shut down due to nitrogen – Coral Reefs

● Achieve significant TN & TP reductions by 2018

● “Reuse” 60% of outfall flow by 2025

● After 2025, outfall for wet weather back-up, w/nutrient reductions

6060

South Central Regional

Boca Raton

Broward Co. North

Hollywood

Miami-Dade Central District

Miami-Dade North

LakeOkeechobee

7.7 MGD

6.2 MGD

22.4 MGD

24.1 MGD

48.6 MGD

68.9 MGD

Total = 178 MGD

Legislated Water Reuse RequirementsLegislated Water Reuse Requirements

6161

County /County / Local IssuesLocal Issues

Recharging Groundwater is Essentially a SurfaceRecharging Groundwater is Essentially a SurfaceWater DischargeWater Discharge –– nitrogen concernsnitrogen concerns

6262

Miami Dade CountyMiami Dade County

6363

Miami South DistrictMiami South DistrictWater Reclamation PlantWater Reclamation Plant

● 1st indirect potable reuse project in Florida

● Recharge drinking water aquifer with 23 mgd ofhighly treated wastewater

● Addressing pharmaceuticals and pathogens withregulators and public

● MF, RO, UV-AOP

● Ultra-pure drinkingwater quality

6464

Emerging ContaminantsEmerging Contaminants

PharmaceuticalsPharmaceuticals

PersonalPersonalCare ProductsCare Products

EndocrineEndocrineDisrupting CompoundsDisrupting Compounds

6565

Advanced Oxidation Processes (AOPs)Advanced Oxidation Processes (AOPs)

High dosage UV w/ H2O2

UV ~ 500 mj/cm2

H2O2 ~ 1-3 ppm

UV – TiO2

Ozone

6666

OXIDIZING SPECIESRELATIVE OXIDATION

POTENTIAL (V)

Hydroxyl Radical 2.05

Ozone 1.52

Hydrogen Peroxide 1.31

Permanganate 1.24

Chlorine Dioxide 1.15

Chlorine 1.00

IncreasingIncreasingability toability todegradedegradepollutantspollutants

Data from Metcalf & Eddy, 2003

Hydroxyl Radical (OH°) is a very strong oxidant!

6767

MiamiMiami--Dade CountyDade County

Miami Dade South District WRPMiami Dade South District WRP

6868

Example of the complexitiesExample of the complexities

Moat

Note: Locations are conceptual. Intended for discussion purposes only

ProposedBiscayne Wells

Regional Canal

Drainage Canal

6969

BiscayneBiscayne National ParkNational Park is Environmentallyis EnvironmentallySensitiveSensitive

7070

Groundwater Recharge CriteriaGroundwater Recharge Criteria

ParameterParameterMiami DadeMiami Dade

CountyCounty

FloridaFloridaStateState

StandardStandard

TOC -- 3 mg/l

Total Suspended Solids (TSS) -- 5 mg/l

Total Nitrogen (TN) -- 10 mg/L

Ammonia 2.8 mg/l

0.5 mg/l

--

Total Phosphorus (TP) .003 mg/l --

Emerging Contaminants Yes No

7171

Precedent Setting Treatment LevelsPrecedent Setting Treatment Levels

7272

Plantation, FL Pilot StudyPlantation, FL Pilot Study

7373

WWTP Located Near Canal That CouldWWTP Located Near Canal That CouldRecharge the Biscayne AquiferRecharge the Biscayne Aquifer

East HollowayCanal

EastWellfields

CentralWellfields

PlantationWWTF

7474

Pilot GoalsPilot Goals

● Demonstrate technologycan meet water quality

» TN

» TP

● Unregulated Parameters

» Microconstituents

» Toxicity

» Algal growth potential

» Hormonal impacts

7575

Things to considerThings to consider

7676

Nutrient ControlNutrient Control

● What is thetechnologynecessary to meetthe stringent TN &TP limits?

● Biological vsChemical nutrientremoval

● Are ROmembranesnecessary?

7777

Aquatic Organism ImpactAquatic Organism Impact

● Whole effluenttoxicity (WET)tests

● Is the ROpermeate toxic?

● Will the effluentcause anyhormonalimpacts?

7878

MicroconstituentsMicroconstituents

● Whichmicroconstituents arein your wastewater?

● What technology willmost effectivelyremove them?

● Aremicroconstituentsreally a concern atthese concentrations(ng/L)?

7979

Recharge ModelingRecharge Modeling

● Does yourpoint ofdischarge “off-set” yourwithdrawalimpacts?

● Can you get a1/1 credit?

● What happensduring the wetseason?

8080

SustainabilitySustainability

● Is this reallysustainable?

● Water Supplyvs CarbonFootprint?

8181

Public OutreachPublic Outreach

● How do youchange the “Sewerto Tap” mentality?

● How do youinvolve the publicearly in theproject?

8282

CostsCosts

● Capital cost

● Energy costs

8383

Plantation PilotPlantation Pilot

8484

Broward CountyBroward CountyCanal Recharge Effluent LimitsCanal Recharge Effluent Limits

ParameterParameter Effluent LimitEffluent Limit

TN < 1.5 mg/L

TP < 0.02 mg/L

Nitrate < 10 mg/L

Ammonia < 0.02 mg/L

TSS < 5.0 mg/L

CBOD5 < 10.0 mg/L

BOD < 5.0 mg/L

8585

MBR SchemeMBR Scheme

8686

Conventional Treatment SchemeConventional Treatment Scheme

8787

MBR Scheme DataMBR Scheme Data

8888

Plantation AWT MBR SchemePlantation AWT MBR Scheme

RO/UVPilot TrailerMBR Pilot

8989

Total nitrogen removal ofTotal nitrogen removal ofMBR and RO Pilot UnitsMBR and RO Pilot Units

9090

Total phosphorus removal ofTotal phosphorus removal ofMBR and RO Pilot UnitsMBR and RO Pilot Units

9191

Conventional Treatment DataConventional Treatment Data

9292

Plantation AWT ConventionalPlantation AWT ConventionalTreatment SchemeTreatment Scheme

UF/RO/UVPilot Trailer

DenitrificationFilter Pilot

9393

Total nitrogen removal ofTotal nitrogen removal ofDeep Bed Filter and RO Pilot UnitsDeep Bed Filter and RO Pilot Units

9494

Total phosphorus removal ofTotal phosphorus removal ofDeep Bed Filter and RO Pilot UnitsDeep Bed Filter and RO Pilot Units

9595

ConclusionsConclusions –– Nutrient RemovalNutrient Removal

● Both pilots met stringent TN & TP limits

● RO membranes are necessary to meet TP limit

● Membranes alone (UF/RO) with no chemicaladdition met TN & TP limits

9696

MicroconstituentsMicroconstituents

9797

What are Microconstituents?What are Microconstituents?

● Pharmaceutically Active Compounds (PhAC)

» Ethynyl Estradiol

» Sulfamethaxazole

● Personal Care Products (PCP)

» Triclosan

» Toiletries, cosmetics, fragrances

● Endocrine Disrupting Compounds (EDC)

» Bisphenol-a

» Atrazine

» DEET

Triclosan

DEET

Ethynyl Estradiol

9898

Co

ncen

trati

on

(ng

/l)

MicroconstituentsMicroconstituents ––RO Influent ConcentrationsRO Influent Concentrations

9999

Co

ncen

trati

on

(ng

/l)

MicroconstituentsMicroconstituents –– Most wereMost wereremoved by RO membranesremoved by RO membranes

100100

Aquatic Organism Toxicity TestingAquatic Organism Toxicity Testing

101101

Is the RO permeate toxic?Is the RO permeate toxic?

● RO permeate is too clean

» RO re-stabilization/re-mineralization

» Added salts and minerals

● How would this work full scale?

» Dilution

» Mixing zone

102102

Does RO PreDoes RO Pre--treatmenttreatmentaffect toxicity?affect toxicity?

● RO Pre-treatment

» Antiscalant

» Chloramines

● Pilot Results

Water Flea

Fatheaded Minnow

103103

SummarySummary

● The pilot demonstrated to meet stringent nutrientlimits at different test conditions.

● RO membranes are necessary for surface waterdischarge due to stringent TP limits.

● Almost all microconstituents were removed byRO system.

● RO permeate could be toxic re-stabilization/re-mineralization is necessary.

● The observed toxicity to aquatic organisms waslikely caused by chloramines. Other forms of ROpretreatment should be evaluated.

104104

University of ConnecticutUniversity of Connecticut

Advanced Reuse ProjectAdvanced Reuse Project

105105

University of Connecticut Reuse ProjectUniversity of Connecticut Reuse Project

106106

This is a Spotlight Project

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Potential Uses of Reclaimed Wastewater

ReuseReuseFacilityFacility ►►

▼▼WWTPWWTP

◄◄ Power PlantPower Plant

◄◄ Irrigation SitesIrrigation Sites ►►

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Process Flow DiagramProcess Flow Diagram

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UCONNUCONN Reclaimed Water FacilityReclaimed Water Facility

University of Connecticut– Reclaimed Water Facility

Location Storrs, CT

Capacity 1.0 mgd

Technology Microfiltration +UV Disinfection +Chloramination

Application • Cooling TowerMake-Up Water

• Boiler Feed Water(post RO treatment)

• Irrigation

UniqueChallenges

• Corrosion &Scaling Control forCooling Towers

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MF System Design CriteriaMF System Design Criteria

Parameter Value

Type Pressurized

System Rated Capacity 1 mgd

No. of MF Units 3

No. of Membrane Modules per Unit 32

Membrane Type 0.1 micron PVDF

Specific Design Flux 39 gfd

Minimum Recovery Percent 91%

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UV System Design CriteriaUV System Design Criteria

Parameter Value

Type LPHO

System Rated Capacity 1 mgd

No. of UV Systems 2 + 1

UV Design Dose 80 mJ/cm2

UV Transmittance ≥ 65% at 254 nm

Effluent Turbidity ≤ 0.2 NTU (95% of the time)

Effluent Total Coliform Max. 2.2/100 mL (7 day geometric mean)

Suspended Solids Max. 5 mg/L

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Sustainability FeaturesSustainability Features

● Replaces as much as40% of water supply attimes

● Reclaimed waterreservoir used as aheating source

● Stormwater capture andblending with wastewater

● Solar electricity

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Constructed New Facility?Constructed New Facility?

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Summary and ConclusionsSummary and Conclusions

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Summary and ConclusionsSummary and Conclusions

● Nitrogen control programs are growing

● Very low nitrogen requires significant energy and $

● Range of treatment options

● Good experiences and resources in other states todraw upon