Direct-Contact Molten Metal Biomass Gasification Keith J. Bourne and Mark K. Dietenberger • USDA Forest Service • Forest Products Laboratory • Madison, WisconsinMark H. Anderson • University of Wisconsin • Madison, Wisconsin

�e Forest Products Laboratory and the University of Wisconsin–Madison have developed a novel concept for a direct-contact molten metal biomass gasi�er. A patent is proceeding through the application process [1] and various experiments are underway to test the concept. Currently, several experiments have been completed on a bench-scale proof of concept liquid metal pyrolysis unit. �at unit showed this to be a promising concept requiring further experimentation. An experiment to determine the kinetics of some of the key gas reactions in liquid metals has been designed and is being built. Meanwhile, the design and construction of a 7.5 kg/hr room-scale liquid metal gasi�er is underway.

�is new concept involves introducing wet biomass into a liquid metal at approximately 200°C where the moisture is driven o� without breakdown of the biomass. �e dried biomass is then forced into the bottom of a high temperature (600-1,000°C) melt of the same metal where rapid pyrolysis, tar cracking, and gasi�cation all occur. Emerging at the top of the melt is relatively clean, high-quality syngas as well as minimal char and ash that can be skimmed o� and converted into other value added products.

�e major advantage of using liquid metal to gasify biomass is that it allows for several steps that are traditionally done by separate devices to be combined into one unit. �e liquid metal concept allows for biomass drying, pyrolysis, gasi�cation, and syngas clean-up all to take place in the same unit, all within the liquid metal.

A bench-scale pyrolysis unit was built to prove the concept of liquid metal pyrolysis as well as to conduct an initial optimization of temperature and pressure.

�e unit consists of a pressure vessel made of type 304 L stainless steel that is �lled with approximately 4.3 kg of Lead Bismuth Alloy 255 (melting point 124°C).

A nominally 0.09-gram sample of cardboard or red pine is a�xed to the end of a stainless steel rod that is actuated by a pneumatic cylinder. When actuated, the rod and sample rapidly move from the melt at the top of the vessel (which is held at 180°C) to the melt at the bottom (which is held at a temperature between 600 and 1,000°C).

When the sample reaches the high-temperature melt, rapid pyrolysis occurs. Various temperature and pressure measurements are taken as well as gas concentration measurements with a Pfei�er Vacuum QMS 200 Quadrupole RGA equipped mass spectrometer.

�e next stage in development of the molten metal gasi�er concept is to test a gasi�er with all of the functionalities of a full, industrial-scale gasi�er but at a smaller, more easily modi�able, and cost e�ective scale.

In order to function as a powerful research tool, this modular, small-scale gasi�er is designed to provide• Continuous feed capability up to 7.5 kg/hr,• Variable feedstock and feed rates,• Wide range of process temperatures and

pressures—up to 1,000°C at 690 kPa (100 psig),• Easy modification, and• A full array of measurement capabilities including

full gas analysis. �e feed system will include two reciprocating plungers to force biomass through the system at a rate that can vary up to 7.5 kg/hr in a continuous manner while maintaining a seal allowing the entire system to reach high pressure. Use of a combination of stainless steels and technical ceramics allows the system to safely operate at temperatures up to 1,000°C at pressures up to 690 kPa.

Design and construction of this gasi�er are underway. With this gasi�er we will be able to• Obtain realistic efficiencies,• Optimize temperature, pressure, and catalyst

additions for various feedstocks, and• Test materials and methods of construction for a

future large-scale gasi�er.

A series of experiments have been designed to gain a better understanding of how the chemical reactions involved with gasi�cation of biomass occur within a liquid metal.

�ese experiments will determine how the rates and equilibrium of some key reactions are a�ected when taking place in bubbles �owing through a liquid metal melt at di�erent temperatures and pressures.

Key reactions to be investigated are• Water–gas shift and• Hydrocarbon reforming.

�e experimental design consists of a reaction chamber �lled with liquid metal or another substrate that can be heated to 1,000°C and pressurized to 690 kPa. Various gases can be metered into the bottom of the reactor where they will be mixed and slowly bubble up to the surface. �e composition of the gases will then be measured with a gas sample train similar to that shown in Figure 5.

Figure 5. Schematic of lab-scale continuous flow gasifier.On the left is the feed system capable of continuously feeding 7.5 kg/hr of biomass into the liquid metal. �e biomass–liquid metal slurry �ows into the bottom of the gasi�er where buoyancy-induced �ow brings the biomass into the high-temperature zone, which is where pyrolysis and gasi�cation occur. At the top of the gasi�er, the gases enter the gas sampling train while the excess liquid metal, ash, and any remaining char proceed into the cooling/clean-up loop for cooling, separation, and recycling.

Figure 6. 3D rendering of continuous flow gasifier.�e feed system on the left consists of two plungers driven by a lead screw and stepper motors and an angled stainless steel tube leading to the bottom of the gasi�er unit. �e unit is surrounded by �ve high- temperature radiant heaters.

Figure 7. Schematic of gas kinetics experimental design.�is experimental design will be used to investigate the water–gas reaction and hydrocarbon reforming in liquid metals. Gases will be metered into the bottom of the reactor where they will be mixed and allowed to bubble through the liquid metal. �e emerging gases will then be analyzed with a mass spectrometer and gas chromatograph.

Results• Completed pyrolysis in under 3 seconds at 1,000°C

• Produced high-quality syngas

• Converted 14% of sample to gas at 800°C, 100 psia

• Gained experience working with liquid metals in extreme conditions

Proof of Concept: Bench-Scale Pyrolysis Unit

Pneumatic plunger with linear displacement transducer

Plunger rod with sample on end

�ermocouple array

Pressure transducer

Electric radiant heater

0.5 meter tall reactor containing 4.3 kg of lead bismuth

TC5

TC6

TC4

TC3

TC2

TC1

TC0

TC7 TC8

Figure 1. Schematic of proof of concept pyrolysis unit.Vessel containing 4.3 kg of lead bismuth at a temperature ranging from 180°C up to 1,000°C and pressures from atmospheric to 690 kPa (100 psi), into which a biomass sample is introduced for rapid pyrolysis.

0

10

20

30

40

50

60

70

O2COCH4H2CO2Gas component

Mol

ar p

erce

nt o

fpr

oduc

ed g

as

Red pineCardboard

Figure 4. Gas composition for red pine and cardboard samples at 800°C and 1 atm.Both feedstocks produced mainly H₂ and CO under these conditions with minor parts of CO₂, O₂, and CH₄.

0

2

4

6

8

10

12

14

16

800°C,100 psia

800°C,60 psia

1,000°C,15 psia

800°C,15 psia

600°C,15 psia

ConditionPe

rcen

t of s

ampl

e py

roly

zed

by m

ass

Figure 3. Amount of sample converted to gas during pyrolysis under varying conditions.Results show that increasing the temperature of the melt increases the amount of sample converted to gas, while increasing the system pressure shows a more dramatic rise in gas produced through pyrolysis. Increased pressure was not tested at 1,000°C due to limitations of the pressure vessel.

Figure 2. Pressure trace from pyrolysis of cardboard in proof of concept pyrolysis unit. Averaged pressure traces from three di�erent melt temperatures show increased gas production as well as decreased pyrolysis time with increased temperature.

00 1 2 3 4 5 6 7 8 9 10

2

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Pres

sure

rise

(psi

)

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Sample reaches high-temp melt in 0.8 second

Sample isfully injected

in 1.13 sec 20

30

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60

70

80

901,000°C

800°C

600°C

Continuous Flow Gasifier

Gas Kinetics Experiments

References[1] Dietenberger, Mark A., et al. U.S. Patent Application 20080307703. Filed April 24, 2008.[2] Tao, Thomas, et al. Direct Logistic Fuel JP-8 Conversion in a Liquid Tin Anode Solid Oxide Fuel Cell (LTA-SOFC). Technical Report, DARPA-ARMY, ARO, Sept. 4, 2008.

Biomass hopper

Produced gas out

To vent/flare

Capillary

Oxygen-rich liquid metal

400°C heated line

Particulate filter

Feeding biomass/

liquid metal slurry

200°C liquidmetal

Heaters

Steam in

200°C biomass/liquidmetal slurry

600–1,000°C liquidmetal melt

Char and tar reform

ingPyrolysis

Liquid metal refill

SRS UGA 300 mass

spectrometer

Isopropanol impinger bottles

Varian 4900 micro GC

Biomass refill

Liquid metal clean-up

and cooling

Forest ProductsLaboratory

Why Liquid Metal?In this gasi�er concept, liquid metal serves as both an energy exchanger and as a means of transporting biomass through the system. In addition, liquid metal has the potential to reform carbon as described in the following reaction sequence where M represents a generic liquid metal [2].

O₂ (in air) + M => MO₂ MO₂ + C => M + 2CO

In general, all liquid metals have properties that are bene�cial for use in a direct contact gasi�er including • High thermal conductivity, • High heat capacity, and • Low viscosity.

Many liquid metals were considered for use. To select the most desirable metal, the following properties were considered. • Liquid at temperatures from 200°C to 1,000°C • Low vapor pressure in that temperature range • Low toxicity • Low cost • Potential to catalyze gasification reactionsAfter considering these properties, two alloy systems stood out: lead bismuth and tin bismuth. �e two systems are very similar, except lead alloys are lower in cost and have a higher toxicity than tin alloys. Lead bismuth was used for initial experiments due to its availability and low cost. However, tin bismuth was chosen for all subsequent experiments because of its low toxicity in spite of an elevated cost. Tin has also been proven as a catalyst in gasification reactions [2].

Title: Best Practices in Data Handling Security and Advanced Temperature

Measurement Methodology Utilizing Foundation Fieldbus

Authors: Bryce Lawrence | Specialty Services Manager Novaspect, Inc. | 1776 Commerce Dr | Elk Grove Village | IL | 60007 | USA T +1 847 709 8988 or +1 952 975 1583 F +1 847 956 8588 M +1 815 953 1012 blawrence@novaspect.com An Emerson Process Management Local Business Partner Jacek Chmielewski - Renewable Energy Business Unit Manager - Project Execution Team Novaspect Inc. 1776 Commerce Dr, Elk Grove Village, IL 60007 USA M 847.226.5409 T 847.709.8928 F 847.956.8588 jchmielewski@novaspect.com www.novaspect.com An Emerson Process Management Local Business Partner Keith Bentley | Sales Engineer | Rosemount Emerson Process Management | 15 Spinning Wheel Rd #124 Hinsdale | IL | 60521 T +1 630 408 5036 keith.bentley@emerson.com Rosemount Measurement Emerson Process Management | 8200 Market Blvd | Chanhassen | MN | 55317 | USA T: 800 999 9307 F: 952 906 8815 Responsible for correspondence Jacek Chmielewski - Renewable Energy Business Unit Manager - Project Execution Team Novaspect Inc. 1776 Commerce Dr, Elk Grove Village, IL 60007 USA M 847.226.5409 T 847.709.8928 F 847.956.8588 jchmielewski@novaspect.com www.novaspect.com An Emerson Process Management Local Business Partner Key Words Data Security

Temperature Density

Foundation Fieldbus

Abstract Emerson Process Management has recently been the automation R&D partner

to GTI for the Carbona and PWR gasification programs. Two areas of

involvement are of particular interest.

The first one addresses data and therefore IP security handling issues.

As various technologies are being developed, the issues of IP associated with

operating conditions, contacting technology and media, producer and syngas

clean-up methods as well as other considerations are seen as very important. A

secure control system is key in achieving this. Novel process data handling

deployed as part of the ongoing projects are a good example of how the IP

security can be maintained.

The second area of interest addresses issues and solutions associated

with high density temperature measurements, utilizing Foundation Fieldbus high

throughput communication bus, especially in the producer and/or syngas regions

of the Gasifier. Accurate and efficient way of handling this issue contributes to

gasification efficiency, lower operating temperature, and better control of the

exiting gas composition as well as improved overall system performance.

Best Practices in Data Handling Security and Advanced Temperature Measurement Methodology Utilizing Foundation Fieldbus

The development of various gasification technologies has gone through a

number of high activity phases of development, beginning in the 1940’s

(Germany), then through the 1970’s (Sasol), and 80’s. Each time during the high

development phases on the technology, process control and automation level of

development has progressed somewhat, however only in the past 10 years or so,

it has been in position to make a significant difference in overall system

performance. Although a number of areas are good candidates for process

control best practices and therefore optimization and potentially better overall

system performance, two are discussed in this paper. These address some of

the most novel solutions.

Data Security

Security begins with the physical environment. It’s surprising how many

users pride themselves on a top-notch security model, but then leave their data

historian in an unlocked server room, or sitting out in a control room. First and

foremost, the server should be in an access and temperature controlled server

room. Within the server room, the data historian should be in an approved,

secured rack or tower enclosure with uninterruptable power supplies. It should

also go without noting that if the server has two power supplies, they should not

be fed from the same power source whenever possible. Lastly, always log off

when the server is not in use. If someone does gain access to the server

cabinet, at least they should have to log in first, not find a server already logged

in as “administrator”.

Once the physical security has been addressed, it’s time to examine the

network. Ideally the data historian server will be on its own domain and be its

own domain controller. This Historian domain will then have a one-way trust with

both the Control system Domain and the Plant Domain, in that it will allow any

authenticated user from either the DeltaV Domain or the Plant Domain access to

it. However, any user that has authenticated on the Historian domain and then

attempts to access either the Plant Domain or the DeltaV Domain will be

challenged for credentials. This architecture is detailed in the diagram below.

Plant Network

Control System Network

Control System Domain

Plant Domain

Historian Domain

Whenever possible, firewalls should be utilized to secure the data

historian from other network segments. This is the case with many data servers,

but it is particularly true with data historians as they often act as the boundary to

process control networks which often do not, or cannot, have the latest security

and anti-virus measures deployed. The security advantage is enormous in that

often the only firewall ports required opened by the data historian are ports 5450

and those used by Windows for Name Resolution, Authentication, and

Administration. These vary depending on the operating systems in use and

network types, but typically include 53 or 137 for Name Resolution and 135 and

445 for Administration. Additional ports may be required depending on the

particular architecture utilized, and other trusts, particularly those associated with

applications, can create the need for additional port openings.

The only true stumbling block for firewall-based security comes with the

use of OPC based communication. Whenever possible, the data historian and

OPC Server should be placed on the same side of the firewall. This is because

OPC, in its current release, utilizes Microsoft’s near-defunct DCOM technology.

DCOM requires all ports above 1024 to be available, roughly 64,000 ports. It is

really not practical to place a firewall between the OPC Server and the

HistorianPI Server because of this limitation. There are third party tunneling

products which can drive OPC through a single port, however, if removing the

firewall from the path is not possible.

The ultimate goal of security in a data historian is to secure the data. The

real key to obtaining Security Nirvana, or as close as one can achieve in this

world, is to setup trusts. One has to create users on the data historian to match

the users coming from the Windows (business network) world. Once the users

have been duplicated in the data historian environment, and groups created on

the data historian server to organize these users, trusts are used to map users,

applications, or connections from the business network into the data historian

users and groups. This allows for users to be placed into whatever access

groups they need to be in without requiring additional user names and

passwords, although that is always an alternative.

Once the groups are established, each point in the data historian must have its

owner and group specified. Finally, once the owners and groups have been

specified, the access level for each should be assigned on a point by point basis.

This specifies the access that the Owner, Group, and World (anonymous) should

have to the point.

By compartmentalizing the data in this fashion, specific users and groups

can be allowed access to certain data and denied access to other data. This

access security is also propagated into the client applications used for reporting

and trending. Once this is complete, all the data in the data historian has been

successfully secured.

Temperature Measurement

Many users across the process industry need to monitor hundreds to thousands

of temperature measurements in a plant to ensure efficient operations. One way for

these measurements to be brought back to the control system is through a direct wired

configuration. While this configuration is quite common in many plants, it does have

some drawbacks. Since each temperature sensor (such as a thermocouple or an RTD)

must be wired back to the control system, there is a high cost associated running long

senor wires. Wiring sensors directly from the process to the control room can induce a

number of different errors into the system. For example, long wire runs are susceptible

to measurement drift from electromagnetic interference or electrical noise. Industry

best practice suggests keeping sensor wires as short as possible to maintain

measurement integrity and reduce the possibility of an inaccurate measurement. The

control system must also have enough capacity for the thermocouple or RTD wires and

their respective cards.

A common alternative to direct wired sensors is the use of a single point

temperature transmitter wired directly back to the control system. Transmitters

compensate and filter weak sensor signals to deliver accurate and stable temperature

measurements, which lowers operating costs. This configuration can allow users to

standardize wiring practices and take advantage of simplified control system I/O cards

to reduce installed costs. Sufficient I/O card space must be available in the control

system, which can be an issue in older plants. The additional cost of the transmitter

and wiring must be considered in the overall installation. The use of a smart transmitter

would also allow users to take advantage of diagnostics that reside within the device

transmitter to troubleshoot installations and reduce maintenance trips to the field, which

results in lower operating costs

These two methods of collecting temperature data are the most pervasive in the

process automation industry. However, in recent years a new trend has developed

which takes advantage of common process design configurations to reduce installation

costs and still offers the high accuracy and repeatability of single point temperature

transmitters. Many plants have situations where multiple temperature measurements

are within close proximity of each other. These measurements often require the

protection and proven reliability of transmitter technology. Typical applications would

include distillation columns, reactor vessels, boilers, heat exchangers, and motor bearing

and wiring temperatures. These measurements can be referred to as high density

temperature measurement applications.

High Density Temperature Transmitters

A high density temperature transmitter is a device which can monitor many

temperature measurements with a single device. This ensures accurate and stable

measurements and allows users to continuously monitor measurement integrity. The

use of a high density temperature transmitter can reduce installation and operational

costs by as much as 70 percent per point when compared to traditional sensor wire

direct application temperature measurements. An example of the three various

configurations discussed can be found in the diagram below.

As shown above, this particular high density temperature transmitter can take up

to 8 inputs and communicates the readings back to the control system via

FOUNDATION™ fieldbus. This not only provides savings of the wiring back to the

control system, but helps to preserves valuable spare input capacity of the existing

system. The transmitters are also designed to be installed next to the process to reduce

T/C or RTD

Cards

Marshalling Panel

Junction

Sensor Lead

I.S. Barriers

Sensors Wired Direct Bundled Sensor

Sensor

Control Room

$$$$$$$

Transmitter

4-20 mA or HART

TransmitterBundled Transmitter

Single Input Transmitters $$$

Transmitter in Junction

Box

Fieldbus Wire

(2-wire)

High Density Transmitters

FOUNDATION fieldbus H1 Card

$

T/C or RTD

Cards

Marshalling Panel

Junction

Sensor Lead

I.S. Barriers

Sensors Wired Direct Bundled Sensor

Sensor

Control Room

$$$$$$$

Transmitter

4-20 mA or HART

TransmitterBundled Transmitter

Single Input Transmitters $$$

Transmitter in Junction

Box

Fieldbus Wire

(2-wire)

High Density Transmitters

FOUNDATION fieldbus H1 Card

$

sensor wiring costs and maximize savings. All 8 channels are independently

configurable and can be used for a mix of input types including RTD,

thermocouple, mV, ohm, and 4–20 mA signals. Additional functionality includes Input

Selector (ISEL) function blocks which are used to select: Average, Minimum, Maximum,

Midpoint, or First Good Temperatures. The transmitter can share H1 Segment wiring

with other FOUNDATION™ Fieldbus devices.

High density temperature transmitters have been proven to improve start-up

times. Not only does this solution significantly reduce or eliminate long wire runs to the

control room, it eliminates the need for cable trays, extensive loop drawings and large

wiring cabinets in the control room. Installing cable trays, completing loop drawings and

wiring sensors to cluttered wiring cabinets add to installation time and overall costs to

start-up. In addition to eliminating hardware and drawing requirements, high density

temperature transmitters can come with enhanced user interfaces to make configuration

and maintenance easier. Users can use “wizards” which guide them through

configuration steps for sensor types, alerts, engineering units, and more. This makes

configuration simple and easy to do.

Interfacing High Density Temperature Transmitters to the Control System

Depending on whether the legacy host system is currently fieldbus capable or

not dictates the choice for which interface architecture best fits the existing control

system. A system setup with an H1 Fieldbus card currently available to the control

system provides a seamless interface for the connection to the fieldbus segment

containing the high density temperature transmitters. This architecture can then handle

up to 16 high density temperature transmitters per H1 segment warranting up to 128

communicated measurements on one fieldbus segment.

Connecting with systems that do not currently have a fieldbus I/O card requires

a gateway interface to communicate via a protocol understood by the governing control

system. A Fieldbus Interface Module serves as a gateway interface capable of

communicating 4 segments back to the DCS via Modbus or OPC communications. The

gateway’s ability to communicate 4 separate fieldbus segments supports up to 512

temperature measurements if paired with high density temperature transmitter

technology. Each segment can support between 13 and 16 transmitters depending on

whether internal (13) or external (16) power conditioners are being used. This then

supports a range of 416 to 512 temperature measurements depending on the governing

architectural needs. Below is an example of these two different architectures.

DCS with FF I/O

16 devices per segment Up to 128 temperature points

Fieldbus Interface Module

Modbus OPC

DCS

Interfacing to Systems with No FF Interface

Summary

The development of high density temperature transmitters can offer significant

cost savings for temperature measurements, especially in greenfield or brownfield

projects through reduced material and labor costs. They provide dependable

performance and reliability with stable and accurate measurement for trustworthy data.

High density transmitters have enhanced user interfaces, are easy to configure and

install, and require reduced labor and fast start-ups.

The flexibility to take not only temperature sensors, but other inputs such as mv,

ohm and 4-20mA signals, allows tremendous flexibility for the user in incorporating

additional measurement points to the control system. Various interface methods, such

as FOUNDATION™ Fieldbus, Modbus, and OPC allow the devices to be incorporated into

a wide variety of control systems and allows any user to take advantage of the savings

offered by high density temperature transmitters.

DCS with FF I/O

16 devices per segment Up to 128 temperature points

Fieldbus Interface Module

Modbus OPC

DCS

Interfacing to Systems with No FF Interface

Generic Modeling of Biorefinery Business Concept for Investment in

Gasification of Wood Biomass with Syngas to LiquidsMark Dietenberger, Peter Ince, and Ted Bilek, USDA Forest Service

The USDA Forest Products Laboratory (FPL) with the assistance of industrial collaborators is

working on a generic model of integrated biomass gasification business concepts to evaluate

gasification of woody biomass with syngas to liquid (BTL) and/or power at existing forest

product production facilities. This model operates with specified process input coefficients and

production parameters for a base case (existing facility) and a business case with integrated

biomass gasification, BTL and/or power production. The model also considers estimated capital

investment requirements and performs an incremental discounted cash flow and risk analysis for

the hypothetical investment in the integrated biomass gasification concept. The model is

contained in a Microsoft® Office Excel 2003 workbook, and it will be documented and

reviewed, prior to being published. The generic model is designed for preliminary stages of

analysis using conceptual data inputs. If preliminary results look promising, much greater due

diligence and more sophisticated engineering will be needed to support subsequent development

and investment decisions.

The pulp & paper industry is a large consumer of energy as well as wood fiber raw materials,

and therefore integrated biorefining and biomass energy systems are of interest within the

industry. Thermochemical biorefining, based primarily on biomass gasification, is one of the

leading platforms for new business concepts in integrated forest product biorefining (Connor

2007; Thorp et al. 2008a, 2008b). The economic feasibility of the integrated biomass

gasification concept has been explored also in some previously published studies, such as an

assessment of gasification-based biorefining at kraft pulp and paper mills in the United States

developed at the Environmental Institute of Princeton University (Larson et al. 2008, 2009;

Agenda 2020 CTO Working Group 2008a, 2008b). Just within the past year, the concept was

rigorously evaluated with the assistance of U.S. Department of Energy grants at two U.S. pulp

mill locations (at Flambeau River Paper’s mill in Park Falls, Wisconsin, and at New Page

Paper’s mill in Wisconsin Rapids). Indeed, the scope of our model was AFPA's 2020 futuristic

biorefinery Phase I concept, which is the integration of a BTL facility with a wood pulp and

paper mill. FPL extended the scope of the concept to include integrated gas combined cycle

(BIGCC).

While specific concepts have been documented, there has been no generic model that would

enable a potential investor to do a preliminary analysis on a range of possibilities. Such a model,

if publically available, may encourage investors to consider these new methods of energy

generation. The primary objective of this work is to create a generic model that would act as a

template into which users could enter their assumptions about technologies, conversions, and

markets, and to demonstrate how this model can be used to do prefeasibility analysis on the

biorefinery business concept.

To address a wide range of possibilities, our business model features (1) a process model that

can consider up to three different biomass feedstock types, several different kinds of existing

mill configurations, gasification-to-liquid processes, biocrude distillation options, lime kiln

firing with syngas, BIGCC, hog and gas boilers, and steam turbine, (2) a cash flow model

having various business options, including differences between retrofit and base case,

compilation of capital and operating costs of major components, taxation and loan

considerations, and (3) a stochastic risk assessment that links investment outcomes as related to

uncertainties of the input parameters of biomass supply cost and operating costs.

Introduction

AGENDA 2020 CTO Working Group. 2008a. Adding biofuel/bioproduct capacity

to existing U.S. mills; Part 1: Options. Paper 360º (TAPPI Press) Vol. 3, No. 4. April

2008. pp. 33-37.

AGENDA 2020 CTO Working Group. 2008b. Adding biofuel/bioproduct capacity

to existing U.S. mills; Part 2: The Business Case. Paper 360º (TAPPI Press) Vol. 3, No.

6. June/July 2008. pp. 24-28.

Bilek, E.M. (Ted). 2007. ChargeOut! Determining Machine and Capital

Equipment Charge-Out Rates Using Discounted Cash-Flow Analysis. General

Technical Report FPL-GTR-171. Madison, WI: U.S. Department of Agriculture, Forest

Service, Forest Products Laboratory. 33 p.

Connor, Eric J. 2007. The Pathway to Our Bio-Future. PaperAge. March/April

2007. pp. 40-43.

Larson, Eric D., Stefano Consonni, Ryan E. Katofsky, Kristiina Iisa, and W.

James Frederick, Jr. 2008. An assessment of gasification-based biorefining at kraft

pulp and paper mills in the United States, Part A: Background and assumptions. TAPPI

Journal. Vol. 7, No. 11. November 2008. pp. 8-14.

Larson, Eric D., Stefano Consonni, Ryan E. Katofsky, Kristiina Iisa, and W.

James Frederick, Jr. 2009. An assessment of gasification-based biorefining at kraft

pulp and paper mills in the United States, Part B: Results. TAPPI Journal. Vol. 8, No. 1.

January 2009. pp. 27-35.

Thorp, B.A., Benjamin A. Thorp IV, and L. Diane Murdock-Thorp. 2008a. A

Compelling Case for Integrated Biorefineries (Part I). Paper 360º (TAPPI Press). Vol. 3,

No. 3. March 2008. pp. 14-15.

Thorp, B.A., Benjamin A. Thorp IV, and L. Diane Murdock-Thorp. 2008b. A

Compelling Case for Integrated Biorefineries (Part II). Paper 360º (TAPPI Press) Vol. 3,

No. 4. April 2008. pp. 20-22.

References

Early stages of financial investment decisions are often based on highly uncertain

preliminary engineering models of business concepts, so careful attention must be

given to the impact of uncertainty and lack of precision on projected financial outcomes.

Although there is little or no available data on actual commercial-scale integrated

biomass gasification systems, it was found helpful for dialectic purposes to break the

process model into a base case process that describes an existing facility and then its

transformation by capital investment into a business case process by constructing both

a base case and alternative business case model in the spreadsheet.

The particular base case shown above corresponds to a fully functioning wood mill and

a paper kraft mill in which natural gas fires the lime kiln and the bark fuel is burned in

the hog boiler to make steam for power and mill processes. For the business case the

biomass reformer corresponds to steam gasification modified by oxygen trimming,

which explains the inputs of indirect heat, steam, and oxygen into the reformer. The

syngas is cooled with a heat recovery unit and cleaned for the Fischer-Tropsch

synthesis. The syngas can, however, be deflected for use in the BIGCC or lime kiln

depending on meeting the mill requirements. The process model allows for choice in

refining the biocrude. The particular business case shown above corresponds to

displacing natural gas completely, diverting bark from hog boiler to the gasifier, and

burning naptha, leaving wax and diesel as the high value added product.

Energy and Mass Processes Incremental discounted cash flows are used to compare a “base case” without the

gasification technology and a “process case” with gasification technology added. The

base case has pulp, paper, and wood mill facilities without the biomass gas-to-liquid

system. The business case has the gas-to-liquid technology added. The incremental

cash flows are the additional flows that result from the BTL investment. These are the

additional benefits and costs that result from adding the BTL technology.

Net present values, nominal internal rates of return and real internal rates of return are

automatically calculated. These are all calculated three ways: before tax and finance,

before tax, and after tax basis. Different inflation rates can be entered for costs and

revenues. Loan terms can be varied. Depreciation terms can be varied. Three tax

loss treatments are allowed. Documentation of these features is provided in the report

“ChargeOut! Determining Machine and Capital Equipment Charge-Out Rates Using

Discounted Cash-Flow Analysis” (Bilek, E.M. (Ted). 2007).

Results are shown to the right indicating a NPV of $215M and an IRR of 28% for the

particular business case described earlier.

Cash Flow Analysis

Mean of NPV (net present value) / After-tax D8 vs Percentage Change of Inputs

180000000

190000000

200000000

210000000

220000000

230000000

240000000

250000000

-10% -5% 0% 5% 10%

Change From Base Value (%)

NP

V (

net

pre

sen

t valu

e)

/ A

fter-

tax Paper Mill Production: / @RISK distributions AW83

Purchased Biomass Price: / @RISK distributions

AW85

Wax Product Price / @RISK distributions AW87

Price of Electricity Sold to Grid / @RISK distributions

AW89

Operational FT Yield: / @RISK distributions AW91

Diesel Product Price: / @RISK distributions AW93

Capital Cost Adjustment / @RISK distributions AW95

180000000

190000000

200000000

210000000

220000000

230000000

240000000

250000000

Mean of NPV (net present value) / After-tax

Price of Electricity

Paper Mill Productio

Purchased Biomass Pr

Capital Cost Adjustm

Wax Product Price /

Diesel Product Price

Operational FT Yield

Inp

uts

Sensitivity Tornado

We acknowledge that each business concept will likely be different and therefore we

provided the user the ability to specify (1) input feedstock variations of types, quantities,

moisture content and prices, (2) select a variety of base cases and business cases for

biomass conversion, (3) select a variety of financing options for business case

investment, and (4) select a variety of investment risk assessments. For example,

biomass supplies in terms of types, quantities, and prices can vary quite a bit by region

and location, which places responsibility on the user to determine those inputs for a

given local situation. Innovations in growth and harvesting of engineered energy crops

can create additional variations to the local availability and pricing of biomass.

Although we provided feedstock types for wood logs, forest residues, and agricultural

residues, the user can consult an engineer to provide alternative feedstock information,

such as algae or switchgrass that may have different fuel values, ash contents, or

certain other properties.

As for variation of business cases, Table 1 provides hypothetical examples of eight

different types of cases for incremental investments that use biomass gasification

technology. Hypothetical case 7 for example represents the upgrading of a kraft pulp

and paper mill to BTL, and appears to achieve a relatively high after-tax IRR, nearly

28%, while eliminating fossil usage (i.e. no NG nor purchased electricity) via BIGCC

technology, sending all bark fuel to a biomass reformer, and adding naphtha to the tail

gas (used for energy at the pulp and paper mill) instead of selling it as biofuel. In

contrast, hypothetical case 8 provides an even higher IRR, nearly 37%, and higher

NPV, if we allow as much NG to the IGCC component as needed, boosting the GTL to

100% output, and selling naphtha as a biofuel. This results reflect the very high value

added nature of the wax, diesel, and naphtha output, and points out limitations of

gasification options that do not include biofuel production, as the progression from

cases 1 and 2 show.

The cash flow model provides financing options selected by the user that can be

varied. Because there are uncertainties in knowing the precise values of input

variables, particularly in the fluctuations of flow input and output prices, and of the

construction costs, the user has access to probability analysis by implementing

commercially available risk assessment software that can be linked to Microsoft Excel

spreadsheet models.

Although the particular examples we have chosen are representative of the limited

engineering and financial data available to us, the user can consult an engineer and

financial experts to incorporate a more sophisticated set of assumptions.

Wide Range of Concepts

Investment Risk Assessment

We hope that our generic model of integrated biomass gasification business concepts

will help familiarize others with opportunities in this area. As more empirical data is

obtained to fully supplant some of our hypothetical values, some optimization of facility

size can also be achieved, for example, resulting from the feedstock supply costs

increasing with its distance shipped to the facility, along with competition for the

feedstock supply.

Conclusion

Table 1. Few Generic Modeled Cases for Incremental Investment into Biomass Gasification

Case

No.

Base Facility Gasification

Process

Base Net

Income

(Millions)

Integrated

Net Income

(Millions)

Capital

Cost Est.

(Millions)

IRR

Nominal

NPV

(Millions)

1 None Biomass CHP only $0 $39 $185 7.9% $4

2 None Biomass IGCC only $0 $57 $215 22.7% $97

3 None B-IGCC and BTL $0 $66 $206 31.6% $169

4 NG-IGCC B-IGCC and BTL $2 $57 $187 26.8% $119

5 Biomass CHP B-IGCC and BTL $32 $60 $200 28.4% $140

6 Wood/Pulp/Paper

Mill with CHP

B-IGCC, BTL, and

Bark to CHP

$164 $217 $200 24.8% $110

7 Wood/Pulp/Paper

Mill with CHP

B-IGCC, BTL, and

Bark to Gasification

$147 $242 $310 27.8% $215

8 Wood/Pulp/Paper

Mill with CHP

Case 7 and NG to

maximize IRR

$147 $262 $310 36.9% $323

Monetary unit is in million dollars

Biomass fuel rate for all cases are 1200 wtpd of logging residue, and 200 wtpd of scrap biomass

Electric selling rates are $0.1/kWH for Cases 1 through 4 and $0.05/kWH for Cases 5 through 8.

Wh i R t h?Who is Rentech?Cl l tiClean energy solutionIntegrated technologies for:– Biomass to fuels– Biomass to powerp

Rentech was founded in 1981 to commercialize synthetic fuels technology.y gy

Synhytech Plant in operation during the 1990s. This plant housed the largest slurry FT reactors built at the time and is still the largest ever operated in the Western Hemisphere.

Rentech – SilvaGasBiomass GasificationCommercially proven biomass gasificationgasification

Great for power production as ll f lwell as fuels

Commercially demonstrated in yBurlington, VT at up to 400 TPD of wood

PRO Rentech Energy Technology CenterODUC

gy gyCommerce City, Colorado

TDE

10 bpd facility

d d l d f l

EMON

Produces diesel and jet fuel                  (ASTM D7566‐ and D1655‐compliant)N

STRA

Product Upgrading                   technologyA

TIO

technology

NUNNIT

Renewable Energy Complex

Clean Fuels and Renewable Power

gy pRialto, California

Clean Fuels and Renewable PowerProject in Engineeringj g g

Urban wood waste feedstock

– Material now sent to landfill– Material now sent to landfill

600 bpd fuel, primarily diesel ultra‐low sulfur, high‐t di lcetane diesel

Meets and exceeds CA Low Carbon Fuel Standard (LCFS)

35MW of green renewable power

Great fuel for blendingGreat fuel for blending

Up to 1.2 million gallons per year of diesel sold toper year of diesel sold to LAX Airport for ground equipment useequipment use.

Carbon Intensity for Gasoline, Diesel, Biodiesel, BTL Green Diesel and Rentech Renewable Diesel

‐144.0

‐406.0

R Di l®

RenDiesel® + CA Grid Power Disp

RenDiesel® + Coal Power Disp

67.7

76.1

0.0

Natural Gas

Electricity

RenDiesel®

94.7

68.9

76.1

Diesel

Biodiesel

Hydrogen

96.6

99.4

20.4

Gasoline

Ethanol

Cellulosic Ethanol

‐500.0 ‐400.0 ‐300.0 ‐200.0 ‐100.0 0.0 100.0 200.0Carbon Intensity, g CO2e/MJ

Biomass Gasification For Co-Firing in High Efficiency BoilersMetso Power 3430 Toringdon Way, Charlotte, NC 28277Reyhaneh Shenassa

Email: reyhaneh.shenassa@metso.com

Web: www. metso.com/energy

Reyhaneh Shenassa, Vesa Helanti and Juhani Isaksson

MotivationEnvironmental Economical Energy Security

Gasification - To Replace Fossil Fuels and/or to Utilize Demanding Fuels

High efficiency•Broad fuel selection•High volatile content biomass gasify at moderate temperatures•EFW power plant with high efficiency•High efficiency power plant for high alkali/Cl biofuels•Can replace fossil fuels in gas boilers and lime kilns•

Highly Efficient Co-Firing of Product Gas Case for 100 MW Biofuel

100 MW, biofuel Small boiler effiency 25%

25 MW green electricity

100 MW, biofuel Large boiler effiency 40%

40 MW green electricity400 MW, coal + 160 MW coal

electricity

Final outcome 60% more green electricity

Global warming•Lower SO• 2 emission for biomassReduced waste to landfill•

Rural economic development•Negative fuel price for waste•CO• 2 emission allowances costsIncreasing of petroleum fuel costs•

Reduced dependence on •imported fuelsIncreased diversity of energy •supply

Gasi�er

Gasi�er

REF FuelProduct

Gas BoilerGas Cooling & Cleaning

BagFilter

Steam Turbine GeneratorBottom Ash

Fly Ash

Stack

Auxiliary Fuel(Natural Gas, Oil)

Filter Ash

District Heating Power

Current Activities

Gasified waste as the only fuel•Gas boiler 540°C/140 bar•

2 x 80 MW • 400,000 t/a mixed waste•

Lathi Stand-Alone Gasification Plant Process Diagram

Gasify waste at 850 – 900°C•Cool it down to about 400°C•

Filter all dust out and burn clean product gas in gas •fired boiler or PC boiler

All corrosive components, alkali-chlorides, Pb, Zn -will be in solid form

Process Concept

Higher power production efficiencyLower fuel costMultiple fuel sources, flexibility for fuel contractLower investment cost

Economical

BenefitsLow investment compared to stand alone plants•Utilization of large scale steam cycle & high steam parameters•Possible to use lower grade waste as fuel•Tolerance for fuel quality•Less expensive materials in the boiler•

OperationalFluidized bed gasifier is fuel flexible•Main boiler operation is not jeopardized•Most modifications can be completed when the boiler is on-line•Removal of alkali chloride from product gas•

Short shut down required for product gas burner installationAvoid risk of corrosion and fouling/plugging in boiler

EnvironmentalLower CO• 2 emission in proportion to replacement of fossil fuel by CO2 neutral fuel Lower SO• 2 emissions in proportion to use of biomassGasification atmosphere unfavorable for dioxins formation (no free oxygen available)•Product gas cleaned prior combustion • Conditions not favorable for dioxin formation in boiler

Particulate removal including catalyzing metals (Fe, Cu, Al…) -Chlorine removed -

Pulverized peat firing• Reheat boiler 750 t/h, 189 bar, 540°C• Min load with gas only•

Full load gas + peat• Gasifier fuel : mixed waste 500,000 t/a• Fuel input to gasifier 200 MW•

Lathi Energia Oy, Lathi, Finland

Mälarenergi, Västerås, Sweden

Decreases risk of corrosion in coolerDecreases tar condensation in cooler

Product Gas CoolerGas cooler water walls cooled with boiler feedwater•Water temperature controlled by its own circuit•Pressure same as main boiler feedwater pressure•

Rigid and robust•Inorganic fiber composition•Made in one piece•Self supporting - needs no cage•Low density around 0.4 g/cc•90% porosity•Filters process gases•Highly efficient with near zero particulate emissions •

Hot Gas Ceramic Filter

Fuel Handling

Gasifier

Värö Test Rig - Metso CFB Gasifier in operation since 1987 at Värö, Södra Cell, Sweden

High chlorine biofuel gasification for boilers•Waste gasification projects•Clean industrial use•

To demonstrate dust free product gas production

Agreement signed with Södra Cell•Connections installed in spring 2008•Design initiated, test rig installation in fall 2008•Testing started in 2009•Optimization is ongoing•

Status

Intended area for gas cleaning test rig

Installed product gas cleaning test rig

SELECTION AND PERFORMANCE OF 

MATERIALS FORBIOMASS

GASIFIERS JIM KEISER, JAMES HEMRICK, ROBERTA MEISNER, PETER BLAU, AND BRUCE PINT

Production of syngas through gasification or pyrolysis offers one of the more efficient routes for utilization of biomass resources; however, the containment structures used for many of these thermochemical processes are exposed to severe environments that limit their longevity and reliability. Studies have been conducted for three of these systems, and superior alternative materials have been identified. Improved materials will be of even greater importance in proposed gasification systems, many of which will generate even more extreme operating conditions.

Research sponsored by the U.S. Department of Energy, (DOE), Office of Energy Efficiency and Renewable Energy, Industrial Technologies Program, Forest Products Industries of the Future and Industrial Materials for the Future. Research performed at Oak Ridge National Laboratory managed by UT‐Battelle, LLC, for DOE under contract DE‐AC05‐00OR22725.

Improved augers should provide more reliable 

transport of wood chips into 

gasifiers

syngas

Problem:The top of vertical augers lifting wood chips showed severe, localized thinning of the central pipe and cracking/spallingof the weld overlay on the auger flight.

ORNL  Solution:• Examine various augers to determine failure mechanism and frequency

• Design and construct a test facility to evaluate alterative materials

• Assess the market to identify alternate materials

• Fabricate samples from plate, from as applied overlay, and  from ground overlay of candidate materials.

• Conduct wear/corrosion studies.

ORNL Results:• Several weld overlays that show less degradation have been identified.

• An alternative material has been recommended to the gasifier manufacturer.

woodchips

Test system with samples raised

RESULTS FOR  300,000 

REVOLUTIONS

ROTARY EROSION TEST RESULTS

Typical test samples

ROTARY EROSION TEST SYSTEM

VERTICAL AUGER SHOWING WEAR AFTER USE IN GASIFIER

USED AUGER

Ni‐HARD

CURRENT MATL

HA 155

SHS 9192

HA 140

0 0.5 1.0 1.5 2.0 2.5

MASS LOSS (g)

New refractory materials    better withstand hot molten         

salts and compressive stresses in             

gasifiersProblem:The hot‐face  refractory is exposed   to molten salt at 950 to 1,000°C and highly compres‐sive stresses.  Expansion of the refractory lining can create large tensile stresses in the metallic shell. The back‐up refractory is exposed to 800 to 900°C as well as salt components that are transported through hot‐face refractory cracks and joints.  Initially, the refractory lifetimes were less than 3 months.

ORNL  Solution:• Examine refractory samples after exposure in gasifier

• Construct test system and expose candidate materials

• Work with manufacturers to develop new refractories

ORNL Results: Refractory linings installed in October 2006 employed the recommended materials – fusion cast magnesia‐alumina spinel for the hot‐face lining and calcia‐alumina refractory for the back‐up lining. The linings successfully completed 2 years of operation before the gasifier was taken out of service. 

Secondary Air

Black Liquor

Atomizing Steam

Quench Circulation

Pump

RefractoryBrick Lining

GasOutlet

66 GPM270°F 70% DS

13,400 CFM900°F

CoolingWater

Green Liquor

Reactor

Quench

1,750°F

Secondary Air

Black Liquor

Atomizing Steam

Quench Circulation

Pump

RefractoryBrick Lining

GasOutlet

66 GPM270°F 70% DS

13,400 CFM900°F

CoolingWater

Green Liquor

Reactor

Quench

1,750°FReactor

Quench

1,750°F

• Black liquor, steam and air are injected at the top of the gasifier.

• The reactor has a two‐layer refractory brick lining.

• The product gas is removed just below the reactor level.

• The salt is cooled, then dissolved in water at the bottom of the vessel.

Fusion cast magnesia‐alumina spinel hot‐face lining had very little internal cracking after 2 years of operation.

Calcia alumina back‐up refractory showed no evidence of physical degradation, but the XRD data showed some reaction after 9 months of operation.

Laboratory studies to 800°C showed minimal reaction for a sodium carbonate/magnesia‐alumina spinel mixture.

Alternative alloys can improve the durability of 

shield tubes and heater tubes in gasifier 

pulse heater modules

Problem:Shield tubes and heater tubes are exposed to high temperatures (up to 1,000 and 675°C, respectively), combustion gases, unspent fuel, and pulsating combustion pressures. In addition, heater tubes are in contact with Na2CO3 bed particles and endure mechanical stresses.

ORNL  Solution:• Examine  exposed tubes using light microscopy, SEM, and electron microprobe

• Construct test facilities• Identify candidate materials and expose them to simulated gasifier environments

• Evaluate materials for their compatibility with simulated conditions

ORNL Results:Alternative alloys for both shield and heater tubes  have been recommended.

Eductor

BlackLiquor

BedSolids

Product Gas

Steam

Product Gas& Air

Flue GasPulse-HeaterModules

Eductor

BlackLiquor

BedSolids

Product Gas

Steam

Product Gas& Air

Flue GasPulse-HeaterModules

Shield tube materials (330 SS [N08330]and Alloy 800H [N08810]) show high rates of weight gain compared to alternative alloys.

-1

-0.5

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

0 100 200 300 400 500 600 700 800 900

HOURS EXPOSED

MA

SS G

AIN

(mg/

cm2 )

S67956

N12160

N08810

N07214

N06025

S35315

N06045

N08330

N08120

R30556

S32100

APMT

S67956 (HT)

N07214 HT

APMT HT

-202468

10

12141618202224

Tota

l Mas

s G

ain

(mg/

cm2 )

0 500 1000 1500 2000

Time (h) in 100h cycles at 1100°C

Total mass = specimen + spallDashed line: specimen mass

S67956

R30556

N07214

N08810

N08330

N06025N06230

N06230

N06025 Tota

l Mas

s G

ain

(mg/

cm2 )

Shield tube examination showed wall thinning and extensive formation of chromium carbides on grain boundaries (above, left).  Heater tube examination showed severe carburization of type 321 SS with extensive grain boundary carbide formation (above, right).

Mass change vs. exposure time for heater tube alloys exposed in simulated gasifier environment at 675°C.

The Effect of Biomass Feedstock Type and Process Parameters on Achieving the Total Carbon Conversion in

the Large Scale Fluidized Bed Gasification of BiomassKurkela Esa, Moilanen Antero, Nasrullah Muhammad

VTT Technical Research Centre of Finland, P.O.Box 1000, Biologinkuja 3-5, Espoo, FI-02044 VTT, FINLANDphone +358 20 722 111, fax +358 20 722 7048, e-mail: antero.moilanen@vtt.fi

The large-scale production of liquid biofuel based on fluidized bed gasification of biomass and Fischer-Tropsch synthesis process requires high amounts of biomass, which in Finland is primarily forestry-based. The total carbon conversion achieved in the gasifier, operating at temperatures below 1000 ºC, depends mainly on the reactivity of solid char residue. The reactivity of the char residue is affected by temperature, partial pressures of the reactants H2O and CO2 and product gas components H2 and CO, which inhibit the reactivity. The inorganic ash forming material catalyzes the char gasification reactions, and it can create problems due to sintering.

CONCLUSIONSReactivity of biomass char increases with temperature, which is obvious.Increase of pressure does not necessarily mean increase in reactivity. Reactivity of different biomasses, and also different parts of biomass may vary, such as thin pine bark had more than 5 times higher reactivity than thick pine bark, and lower than spruce bark.In general, ash sintering ranged from none to weak, in some cases the sintering was stronger at high pressure than at low pressure at the same temperature.Reactivity in the gas mixture including all the gas components was lower than in 100% steam, increase in temperature increased the reactivity significantly but in higher temperatures, ash sintering was detected.

RESULTS

no sintering weak sintering strong sintering, molten signed 0 signed 1 or 2 stars signed 3 stars

Steam gasification reactivity of spruce bark at various temperatures and in 5 bar pressure of steam: The instantaneous reaction rate as a function of fuel conversion and the fuel conversion as a function of time (right).

Classification of ash sintering degree under microscope.

The tests were carried out in a pressurized thermogravimetric apparatus. Reactivity was expressed as instantaneous reaction rate. Ash sintering degree was detected on the residue under stereomicroscope after the test.

VARIABLES Biomass type: like barks, spruce, pine, birch, aspenTemperature, pressure, product gas composition

CONDITIONSTemperature: 800 - 900°CPressure :1 bar - 20 barGasifying medium:100 vol-% steam; 70 vol-% steam with 30 vol-% H2; 100 vol-% CO2; 70 vol-% CO2 with 30 vol-% CO and a gas mixture containing all the gas components

The steam gasification reactivity of spruce bark in various steam pressures at 850°C.

Temperature Pressure Product gas inhibition

Biomass

Steam gasification reactivity of thin and thick pine bark in 1 and 5 bar steam pressures at 850°C.

Inhibition effect on gasification of spruce bark by adding H2into steam, and CO to CO2 at 850°C and 5 bar pressure (total) with increasing concentrations of H2 (2 bar steam, 0.5 bar and 1 bar H2, respectively, the rest nitrogen) and CO in CO2 (2 bar CO2, 1 bar CO and the rest nitrogen) (right).

The gasification reactivity of spruce bark in the gas mixture containing 1.5 bar steam, 1 bar H2, 1.25 bar CO2, 0.75 bar CO and 0.5 bar N2 (total pressure 5 bar) at various temperatures.

Steam gasification reactivity of barks and needles (right) in 1 bar steam at 850°C.

0

50

100

150

200

75 80 85 90 95 100Fuel conversion (ash free), %

Inst

anta

neou

s re

actio

n

rate

, %/m

in 900 °C

850 °C

800 °C

°C (*)°C (o)°C (o)

70

75

80

85

90

95

100

0 2 4 6 8Time (min)

Fuel

con

vers

ion

(ash

free

), %

900°C (*) 850°C (o)

800°C (o)

0

50

100

150

200

75 80 85 90 95 100Fuel conversion (Ash free), %

Inst

anta

neou

s re

actio

n

rate

, %/m

in

10 bar

5 bar

1 bar

5 bar 1 bar

Fuel conversion (Ash free), %

Needles

0

50

100

150

200

75 80 85 90 95 100Fuel conversion (Ash free), %

Inst

anta

neou

s re

actio

n ra

te, %

/min

0

50

100

150

200

75 80 85 90 95 100Fuel conversion (Ash free), %

Inst

anta

neou

s re

actio

n ra

te, %

/min

Aspen bark (o)

Birch bark (o)

Spruce bark (o)

Pine bark (o)

0

50

100

150

200

70 75 80 85 90 95 100Fuel conversion (Ash free), %

Inst

anta

neou

s re

actio

n ra

te, %

/min 100% steam (o)

10% inhibition of H2 (o)

20% inhibition of H2 (o)

0

50

100

150

200

70 75 80 85 90 95 100Fuel conversion (ash free), %

Inst

anta

neou

s re

actio

nra

te, %

/min

800 C (o)850 C (o)

875 C (*)

900 C (**)

0

50

100

150

200

70 75 80 85 90 95 100Fuel conversion (Ash free), %

Inst

anta

neou

s re

actio

n ra

te, %

/min

100% CO2 (*)

20% inhibition of CO (o)

Inst

anta

neou

s re

actio

n

rate

, %/m

in

0

50

100

150

200

70 75 80 85 90 95 100Fuel conversion (Ash free), %

Pine bark thick

Pine bark thin

0

50

100

150

200

70 75 80 85 90 95 100

Inst

anta

neou

s re

actio

n ra

te, %

/min

Pine bark thick

Pine bark thin

70

75

80

85

90

95

100

0 5 10 15 20 25 30Time (min)

Fuel

con

vers

ion

(ash

free

), %

800 C

850 C

875 C (*)

900 C (**)

o * ** indicate ash sintering (see Fig. above)

o * ** indicate ash sintering (see Fig. above) o * ** indicate ash sintering (see Fig. above)

Gasification of Biomass - ReducinG fossil fuel use foR Heat & PoweRdejan sparica, amanda fjeld, Yan li, duncan meade, cliff mui, nesho Plavsic and Rick Vandergriendt

www.nexterra.ca

Kruger Products, new westminster, BcApplication: Tissue Mill – Process Steam

Capacity: 40,000 lbs/hr 300 psig saturated steam

nexterra Product development center, Kamloops, BcApplication: Research and Product Development

Capacity: 10 MMBtu/hr input

tolko industries, Kamloops, BcApplication: Plywood Mill – Heating System for Veneer Dryer and Log Conditioning Vats

Capacity: 38 MMBtu/hr net useable heat

Nexterra Systems Corp. has developed a simple, clean and efficient gasification technology, which converts wood residuals, such as bark, into synthesis gas or “syngas”. The first generation of the technology, based on a fixed-bed, updraft gasification approach, has been extensively researched, developed and commercially deployed for heat and steam applications. A number of facilities have been built, including systems at Tolko Industries in Kamloops, British Columbia and at the Columbia Campus of the University of South Carolina.

The second stage of product development involved the conveyance and direct firing of syngas into rotary kiln and boiler burners. Nexterra has performed successful trials of these direct-fire applications at pilot scale and is in the process of commercializing this solution with a first installation at the Kruger Products tissue mill in New Westminster, B.C.

Nexterra is currently developing the third generation of its platform technology which will enable syngas to fuel stationary internal combustion engines coupled to electrical generator units. In collaboration with GE Energy and its gas engine division, GE Jenbacher, Nexterra is developing a new commercial biomass gasification-to-power solution ranging in size from 2 – 10 MWe. This work is being conducted at Nexterra’s Product Development Center in Kamloops, B.C., where a 250 kWe Jenbacher is being installed.

technology RoadmapApplication Development

2005/6

1. Indirect-Fired Heating System

Output: Process heat, hot air, • steam, hot water

Apps: Industrial, commercial • and institutional heating systems

2007/8

2. Direct-Fire Syngas Lime Kilns/Boilers

Output: Hot syngas delivered • to kilns or boilers to produce steam

Apps: Direct-firing existing • boilers and lime kilns

2008/10

3. Direct-Fire IC Engines

Direct-Fire IC Engines• Output: Electricity and heat •

via IC enginesApps: Small scale CHP <10 •

MWe direct fired with clean syngas

2009/10

4. Co-Fire Aero-derivative Gas Turbines

Co-Fire Aero-derivative Gas • Turbines

Output: Electricity via Aero • derivative GTs

Apps: Medium scale 50 – 100 • MWe co-fire 15 – 25% cleaned, upgraded syngas with natural gas

2010+

5. Synthetic Fuels and Chemicals

Output: Methane, Ethanol • other fuels

Apps: Medium Scale 100 – • 150 MMBtu/hr clean, upgraded syngas plus FT or other conversion process

UniquenessDifferentiationCompetitivenessFuel Diversification

nexterra systems corp.

technology RoadmapFuels Development

2005/6

2007/8

2008/9

2010+

Wood - Mill Residue Wet & Dry Bark

C&D Wood/Eng. Wood

AgWaste & Residuals

Biosolids

second Generation - direct fired thermal energyApplications: Retrofit, Industrial, Institutional

Capacity: 10 - 100 MMBtu/hr

third Generation - electrical Power GenerationApplications: Greenfield, Industrial, Institutional

Capacity: 2 MWe + 2 MWth a 10 MWe + 10 MWth

Biomass Dryer Fuel Storage Bin Gasifier Tar Cracker Precoat Filter

Internal CombustionEngine

Fuel In-Feed Gasifier Syngas Blower

Syngas Burner

Heat RecoveryEquipment

Electrostatic Precipitator (ESP)

Fuel In-Feed Gasifier Oxidizer Boiler Electrostatic Precipitator (ESP)

first Generation - indirect fired thermal energyApplications: Greenfield, Industrial, Institutional

Capacity: 10 - 100 MMBtu/hr

dockside Green, Victoria, BcApplication: Community District Heating System

Capacity: 7 MMBtu/hr net useable hot water

university of northern British columbia, Prince George, BcApplication: Campus District Heating System

Capacity: 15 MMBtu/hr hot water

university of south carolina, columbia, scApplication: Campus District Heating System

Capacity: 72 MMBtu/hr net useable 600 psig superheated steam