Thermal gasification for Power and Fuels

Esa KurkelaVTT - Gasification TeamSeptember 2010

224/03/2011

Gasification

Is a conversion of any carbonaceous fuel to a gaseous product with a useable heating value.

The dominant technology is partial oxidationProduces a gas mixture that contain H2 and CO in varying ratios (synthesis gas). The oxidant may be air, pure oxygen and/or steam.

Synthesis (syngas) gas can be used in the production of power and heat or chemicals similarly as natural gas

324/03/2011

Gasification is an endothermic thermal conversion technology where a solid fuel is converted into a combustible gas.

GASIFICATION?

air/steam

feedstockadditves

fuel gas

C+O2-> CO2

2C+O2-> 2CO

C +H2O -> H2+CO

etc.

ash

850…1000oC

CO, H2, CH4, CO2, H2O, N2,CxHy

424/03/2011

Coal

Oil

Biomass

Waste/SRF

O2Air

Steam

Syngas

Energy(Fuel gas)

Gasification

SOFC IGCCCo-firingGas engine CHP

FT-synthesisHydrogenSNGMetOH

CARBON

-”partial oxidation”

- combustible product gas

GAS

CLEANUP

524/03/2011

Vesa Mikkonen, ÄänekoskiBuick Le Sabre STW, -83engine volume 5,0 l, power gasol. 145 hpgasifier: own designfuel capacity 130 kg peatdrive length/batch ca. 300 kmfuel cost ca. 2 c/km

Osmo Yli-Kärkelä, Kihniö

Suomen Ekoautoilijat ry

Amateur gasifiers for cars in Finland in the 21st century

624/03/2011

724/03/2011

Gasification phenomenonFuel is fed to the reactor

Water (moisture) and volatiles are released (pyrolysis) rapidlyResidual carbon reacts slower

Reactions depend on the characteristics of biomass

H2O Volatiles

Residual carbon

20°C 100 °C

Ash

---- 850 °C---- 600 °C

824/03/2011

Main reactions of gasification

Gasification of carbon T > 700°C – binds heat C + H2O CO + H2 136 kJ/mol = 11.3 MJ/kg C C + CO2 2CO 170 kJ/mol = 14.2 MJ/kg C(C + 2H2 CH4 )

Water-gas-shift reaction (WGS) – produces heat (small amount):CO + H2O H2 + CO2. 34 kJ/mol = 2.8 MJ/kg C

Combustion – produces heatC + O2 CO2 395 kJ/mol = 32.9 MJ/kg C

Reactivity is controlling final carbon conversion

Oxidation reactions are generally faster andO2 is consumed rapidly in gasifiers

924/03/2011

Example of product gas composition (air gasification, dry gas)fluid-bed gasifier, saw dust, P = 5 bar, T = 860 – 1000°C

vol-%

CO 12

H2 11

CO2 16

N2+Ar 57

C2 -hydrocarbons

0.2

NH3 0.05

Kurkela, E., Laatikainen, J. & Ståhlberg, P. (1993) Pressurised fluidised-bedgasification experiments with wood, peat and coal at VTT in 1991-1992. Part 1.Test facilities and gasification experiments with sawdust. Espoo, VTT Publications161. 55 p. + app. 2 .

1024/03/2011

Gasification reactors

1124/03/2011

GASIFIERS

UPDRAFTOutput < 10 MWth (biomass)Feedstock size 10 - 100 mmMoist feedstock < 50 p-%Gas temperature < 300 °C"Dirty" gas

Examples:Bioneer gasification district heating plants (late 1980’s)Lurgi coal gasifiers at Sasol

DRYING

OXIDATION

PYROLYSIS

AIR

FEEDSTOCK

REDUCTION

GAS

1224/03/2011

GASIFICATION REACTIONS

AIR

FEEDSTOCK

GAS

DRYING:fuel H2O + dry fuel

PYROLYSIS:fuel tars + gases + carbon

GASIFICATION:C + H2O(g) CO + H2 H°1000 = +135.9 kJ/molC + H2O(g) ½CH4 + ½CO2 H°1000 = +5.8 kJ/molC + CO2 2CO H°1000 = +167.7 kJ/molCO + H2O(g) CO2 + H2 H°1000 = -32.2 kJ/mol

OXIDATION:C + O2 CO2 H°1000 = -395.2 kJ/mol

Thermoneutral reaction for carbon:1.34C + 0.34O2 + H2O(g) 0.34CO2 + CO + H2 => min. ratio O2/C = 0.25

1324/03/2011

GASIFIERS

DOWNDRAFTOutput < 2 MWthFeedstock size 10 - 100 mmDry feedstock < 20 p-%Gas temperature < 800 °CClean gasThe most common gasifier type

Used in 2nd world war time in cars and trucs and boats“Häkäpönttö” in FinnishNumerous development trials since 1980’s – no major break through

DRYING

PYROLYSIS

GAS

AIR

FEEDSTOCK

OXIDATION

REDUCTION

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GASIFIERS

FLUIDIZED BEDOutput > 20 MWthFeedstock size <10 mmGas temperature < 800 °C

BUBBLING FLUIDIZED BED (BFB)Fluidizing velocity 1 - 3 m/sLong residence time

CIRCULATING FLUIDIZED BED (CFB)Fluidizing velocity 3 - 10 m/sHigher output/diameterReactive feedstocks

FEEDSTOCK

AIR

ASH

GAS

1524/03/2011

GASIFIERS

ENTRAINED FLOWOutput > 100 MWthFeedstock size <0.1 mmCoal, oxygen gasificationGasification temperature 1300 - 1700 °CUsually pressurised reactorsTexaco, Shell, Prenflo

Leading gasification technology forcoal gasification

GAS

SLAG

FEEDSTOCK OXYGEN & STEAM

1624/03/2011

GASIFICATION TECHNOLOGIES

GASIFICATION METHOD

AIR OXYGEN INDIRECT steam + oxygen/circulating bed material

GAS HEATING VALUE

3 - 7 MJ/m3n 7 - 15 MJ/m3n 7 - 15 MJ/m3n

SIZE RANGE small - medium < 100 MWth

large > 100 MWth medium - large > 50 MWth

FEEDSTOCK reactive: biomass, refuse derived fuel (RDF)

coal, bottom oils biomass

APPLICATIONS CHP syngas, power, (CHP)

syngas

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PRESSURIZED

ATMOS-

PHERIC

PARTIAL

TOTAL

FLUID-BED

FIXED - BED

ENTRAINED FLOW

OTHER TYPES

INDIRECT

OXYGEN

AIR

WET SCRUBBING

HOT GAS CLEANUP

Gasifier operation pressure

Degree of gasification

Reactor type Gas cleanupHeat production

Coal-IGCC

Biomass-engine

Coal-GFBCC(FW)

REF-gasifier+ boiler

GASIFICATION TECHNOLOGIES

1824/03/2011

PRESSURIZED

ATMOS-

PHERIC

PARTIAL

TOTAL

FLUID-BED

FIXED - BED

ENTRAINED FLOW

OTHER TYPES

INDIRECT

OXYGEN

AIR

WET SCRUBBING

HOT GAS CLEANUP

Gasifier operation pressure

Degree of gasification

Reactor type Gas cleanupHeat production

Coal-IGCC

Biomass-engine

Coal-GFBCC(FW)

REF-gasifier+ boiler

GASIFICATION TECHNOLOGIES

Biomass gas-engine process

1924/03/2011

PRESSURIZED

ATMOS-

PHERIC

PARTIAL

TOTAL

FLUID-BED

FIXED - BED

ENTRAINED FLOW

OTHER TYPES

INDIRECT

OXYGEN

AIR

WET SCRUBBING

HOT GAS CLEANUP

Gasifier operation pressure

Degree of gasification

Reactor type Gas cleanupHeat production

Coal-IGCC

Biomass-engine

Coal-GFBCC(FW)

REF-gasifier+ boiler

GASIFICATION TECHNOLOGIES

Waste gasification for power

2024/03/2011

PRESSURIZED

ATMOS-

PHERIC

PARTIAL

TOTAL

FLUID-BED

FIXED - BED

ENTRAINED FLOW

OTHER TYPES

INDIRECT

OXYGEN

AIR

WET SCRUBBING

HOT GAS CLEANUP

Gasifier operation pressure

Degree of gasification

Reactor type Gas cleanupHeat production

Coal-IGCC

Biomass-engine

Coal-GFBCC(FW)

REF-gasifier+ boiler

GASIFICATION TECHNOLOGIES

Coal IGCC (Integrated Gasification Combined Cycle)

2124/03/2011

Power Production from Biomass and Solid Recovered FuelsGasification based systems for different size classes

Fixed-bed gasifier + microturbine

Fixed-bed gasifier +

Fixed-bed gasifier + gas / diesel engine

Fixed-bedgasifier +steam cycle

Fixed/fluidised-bed gasifier & co-firing in natural gas engines

Fluidised-bed gasifier connectedto existing coal- or oil-fired boilers

Gasification + fuel cell + gas turbine and/or steam cycle

Simplified IGCC based on pressurised gasific.or co-comb. in NGCC

Long-term

Short-term

Power, MW0.1 1 5 10 50 100 200

fuel cell + CHP

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GAS CLEANUP

2324/03/2011

Impurities in (biomass) gasification gas

H2

Particulates

CO2

CO

H2O N-compounds

H2S

C2H4

CH4

HCl

TARS- naphthalene, PAH

CLOGGING, SOLID DEPOSITS- pipes- filters- engine ducts

NITROGEN COMPOUNDS- NH3, HCN

Will cause NOx-emissions

2424/03/2011

Always high amounts at the gasifier outletParticulates, alkali- and heavy metals, tars, nitrogen compounds

Gas has to be cleaned before utilisation (except in direct combustion applications)

Gas cleanup is the most crucial problem in the development of advanced gasification based processes

Engine, turbine and fuel cell power plants and Syntheses

Impurities in gasification gas

2524/03/2011

Product gas cleaning

Filtering•Ceramic or bag filter•Particulates removed•Alkali and heavy metals and Cl removed

Catalytic decomposition•Monolith or fluid bed reactor•Tar and ammonia decomposed

Scrubbing•Venturi, spray tower, packed bed column•Ammonia by acid scrubbing•Tar not removed

In the gasifier•Limestone/dolomite additives•Partial decomposion of tars•Sulfur capture (coal gasification)

Ultra cleaup and gas conditioning for synthesis applications•Removal of Sulphur and other contaminants to ppb levels• Shifting the H2-toCO ratio and removal of CO2

2624/03/2011

What is tar?

Pentti Vesterinen operating a tar-burning pit in the late 19th century

Traditionally obtained by dry distillation of wood (slow pyrolysis)

-Paint

-Multipurpose substance:

”if sauna, vodka and tar won't help, the disease is fatal”

2724/03/2011

- peat- biomass- coal

TAR• mixture of numerous organic compounds•liquid at room temperature

What is tar?

•No explicit definition

•Composition depends mainly on temperature history:

•High temperature tar > 750 °C•Formed by secondary reactions of the primary pyrolysis products, C2 intermediates play important role•Fluidisd bed, downdraft gasifiers•Most abundant components:benzene, toluene, naphthalene, fenanthrene

•Low temperature tar < 750 °C•Primary pyrolysis products•Composition depends on fuel, wood: lot of phenolics•Updraft gasifier

2824/03/2011

Component Gas pipe Temp.

708 720 730 740

Benzene 3354 3312 3396 3144Pyridine 32 30 28 281H-Pyrrole 9 9 7 8Toluene 279 229 203 128Ethenylbenzene 36 30 23 16m-Xylene 13 9 7 2Ethynylbenzene 5 6 6 4Styrene 126 108 101 64o-Xylene 4 0 0 0Benzaldehyde 49 37 28 14Phenol 1092 836 607 373Benzonitrile 7 7 7 64-Methylstyrene 126 110 96 60Indene 48 41 40 30o-Cresol 45 26 15 8p-Cresol 23 15 7 0m-Cresol 80 47 27 13Naphthalene 677 630 633 504Quinoline 7 6 5 6Isoquinoline 7 3 2 01H-Indole 4 2 2 42-Methylnaphthalene 30 23 19 111-Methylnaphthalene 18 15 13 8Biphenyl 46 39 34 242-Ethylnaphthalene 2 0 0 0Acenaphtylene 85 84 85 68Acenaphthene 7 6 4 4Dibenzofurane 139 137 119 106Bibenzyl 21 9 4 82-Methyl-1-Naphthol 13 6 0 0Fluorene 6 6 4 4Phenanthere 198 132 104 106Anthracene 23 14 11 124H-Cyclopenta(def)Phenantherene 12 6 4 7Fluoranthene 81 43 34 59Benz(e)acenaphthylene 11 8 6 8Pyrene 72 36 24 50

Benzenebp. 80 °C

Light tarCompounds, 1 ringbp. 80 – 210 °C

Naphthalene, 2 -ringbp. 218 °C

Light PAHCompounds, 2 – 3 ringsBp. 220 - 300 °C

Heavy PAHCompounds, 3 or more ringsBp. > 300 °C

2924/03/2011

Vapour pressure of tar compounds

0.1

1

10

100

1000

10000

100000

0 20 40 60 80 100 120 140 160 180 200 220

Temperature (°C)

Pres

sure

(Pa)

naphthalene solidnaphthalene liquidanthracene liquid

solid

vapour

liquid

Triple point

3024/03/2011

plugging of pipinghttp://www.thersites.nl/

fouling of equipment http://www.thersites.nl/

3124/03/2011

Gascooler

Filter

Fuelfeeding

Gasburner

Coalburners

Bed material/Ca-basedadditive

Sorbent

Gas cleaning: gas cooling followed by filtration

Removal of char & ash particles

But also removal of•Alkali metals•Heavy metals•Chlorine

(by sorbent injection)

3224/03/2011

http://www.schumacher-usa.com/filtration/hotgas.htm

Rigid ceramic candle filters

3324/03/2011

Alternatives for rigid ceramic candle filters

Ceramic fabric filters

3M/ FB 700

Rigid ceramic fibre filtersMadison filter / CerafilTenmat/ FireflyBWF/ Pyrotex KE 85etc.

Teflon bags… only in some specific cases (<250oC)

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Removal of chlorine & heavy metals

Filtration temperature range 150 – 800 °CDepends on impurity to be removed, pre-reforming, filter media, etc.

Filter media:Rigid ceramic or metal candle filtersRigid ceramic fibre filters(< 900 °C)Ceramic bag filters (< 500 °C)Teflon bag filters (< 250 °C)

HCl

DUST+Cl

DUST(Sorbent)

FILTER

Clean gas

HCl

3524/03/2011

0,0

10,0

20,0

30,0

40,0

50,0

60,0

70,0

80,0

90,0

100,0

Na K Cl Al Ca Hg Sn Sb As Cd Pb V Mn Co Ni Cu Zn Mo Cr Si Mg

% o

f out

put

Bottom ash Cyclone dust Filter dust Gas

Fuel: SRF (RDF); Ceramic fabric filter (3M FB-900); Cyclone temperature 700-750oC; filter temperature 395oC)

VTT test data from late 1990’s – CFB gasification at atmospheric pressure

3624/03/2011

Scrubbing

Source: http://www.ecn.nl/en/bkm/products-services/olga/

•Scrubber columns•Spray towers•Venturi

•Water not efficient, removes water solubles and condensable tar fraction

•Organic solvents work better:•RME (rape seed methyl ester), Gussing plant•OLGA-process

3724/03/2011

OLGA tar scrubbing process

Developed by ECN (OLie GAswasser)

Based on organic tar solventOperates above water dew pointTwo scrubbing columns: liquid tar in the Collector (COL) and gaseous tar absorption in the Absorber (ABS)Scrubbing liquid from the Absorber with the dissolved tars is regenerated at high temperature in the Stripper (STR) Liquid tars in the collector are separated from the scrubbing liquid and returned to the gasifierWet electrostatic precipitator (W-ESP) not necessary when hot gas filter is applied upstream of the OLGA

Source: http://www.ecn.nl/en/bkm/products-services/olga/

3824/03/2011

AIR (oxidizer)O2

H2

GASIFICATIONGAS

CO2

COH2O

N-compounds

CATALYST500-900 °C

CO, CO2,H2, H2O

N2, H2,H2O

CLEAN GAS

CATALYTIC CLEANUP OF GASIFICATION GAS

CO

CO2

H2

H2O

CH4

CH4

3924/03/2011

Function of catalytic reforming

PRE-REFORMING:

-Removal of condensable tars

-Enables gas filtration

-Controls soot formation indeep reforming

-Enables engine or turbine usein CHP applications

PRE-REFORMER FILTER

SORBENT

•Dust•Cl•Alkali metals•Heavy metals

Deep reformingGas engineGas turbine

4024/03/2011

Reforming catalysts

ZrO2

+ Lower operation temperature ~700 °C+ Tolerates catalyst poisons- Tar conversion not complete- Under development

Nickel+ Decomposes tar and ammonia simultaneously+ Commercially available- Requires high temperature 900 °C- Deactivates easily by coke & sulphur

Precious metals+ High activity- Very expensive- Long-term stability?

0

10

20

30

40

50

60

70

80

90

100

550 600 650 700 750 800 850 900Temperature (°C)

Tar

mod

el c

ompo

und

conv

ersi

on (%

)

Precious metal A Ni ZrO2

H. Rönkkönen et al. Book of Abstracts, 1st International Congress on Green Process Engineering, 24-26.4.2007 Toulouse, France p. 277

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REMOVAL OF particulatestars and hydrocarbonsNH3 and HCNchlorinealkali metalsheavy metals

Gas cleanup steps in advanced gasification applications

PRE-REFORMER FILTER DEEP

REFORMER

Gasification gas cleanup- Under R&D

Syngas processing- Commercial technology

REMOVAL OF Sulphur compoundsResidual nitrogen compoundsResidual hydrocarbonsCO2H2O

4224/03/2011

Application Examples

4324/03/2011

District heat / Steam production

Small Scale

4424/03/2011

Updraft gasifier "Bioneer"

- For boilers and kilns- Tar containing gas- High carbon conversion- Not sensitive to sintering

5 MW district heating plant, Jalasjärvi, Finland, in operation since 1987 with high availability

Fuel silo

Gas boiler

Hot gas -

District heating -

Electricity

Ash

4524/03/2011

Gas engine power plant

Small Scale

4624/03/2011

Small-scale CHP based on biomass gasification + catalytic gas cleaning + IC-engines

Applications:

• Size class 1- 20 MW th, large potential• Electrical efficiency > 25 %, total efficiency

> 80 %• Small district heating plants• Co-combustion in natural gas engines• Saw mills, plywood industry etc.

Biomass

Air

Air

Catalytictar removal

4724/03/2011

Güssing biomass CHP plant

4824/03/2011

Gussingin demo plant:Fuel capacity 8 MWPower 2 MWElectrical eff. 25 %Thermal eff. 56,3 %Investment 10 M€, Share of and EC and national investment support 60 %

Development steps:TUW- 10 kW 1993-1996TUW - 100 kW 1997-2002Gussing/Demo 2002-2004Commercial 2004 =>

Güssing biomass CHP plant

4924/03/2011

Increase of Availability of the Güssing Plant

0

1000

2000

3000

4000

5000

6000

7000

8000

2002 2003 2004 2005 2006

hour

s of

ope

ratio

n

gasifierengine

Source: TU Vienna, Institute of Chemical Engineering

5024/03/2011

Gasification CHP Plant, DenmarkAs result of Carbona’s domestic and international R&D cooperation

SKIVE PROCESS DIAGRAM

DISTRICT HEATING12 MWth

POWER3x2 MWe

GAS FILTER

3 GAS ENGINES

BIOMASS

FLY ASH

2 BOILERS

TO STACK

WATER

GAS SCRUBBER

GAS BUFFERTANK

2x10 MWth

BOTTOM ASH

AIR/STEAM

TAR REFORMERGASIFIER

GAS COOLERS

WOODPELLETS

6 MW POWER12 MW DISTRICT HEAT

BFB GASIFIER

2 GAS BOILERS

3 GAS ENGINES

FLARE

5124/03/2011

Novel power plant: 1.8 MWe + 3.3 MW heat• Supplier: Condens Oy• Kokemäki, Finland

Novel gasifier

Tar reformer

Gas coolerand Filter

Scrubber

Gas engines

5224/03/2011

Requirements for real success stories in small-scale gasification (< 10 MWfuel)

Fuel flexibility with respect to particle size, ash composition and moisture content

Elimination of tars without waste water problems

Effective final gas cleaning to protect gas enginesor small turbines

Automatic operation, good reliability and low service costs (in industrial countries)

High power production efficiency, 30 - 35 %

These requirements are not met by ordinarydowndraft gasifier – gas engine plants

5324/03/2011

Power and Steam

medium-to-large scale scale

5424/03/2011

Bottomash

Gasifier

Coal

540 °C/170 bar

Processing

Biomass

Fly ash

Pulverized coal flames

Gas flame

Natural Gas

60 MW

350 GWh/a -15 % fuel input

1850 GWh/a -80 %

360 MW

100 GWh/a -5 %

Power* 600 GWh/aDistrict Heat* 1000 GWh/a

Biomass Gasification - Coal BoilerLahti, Finland

Source: Kivelä M, Lahti Energia, 2002

5524/03/2011

CFB GASIFIER

REACTOR

850 °C

900 °CBIOFUEL FEED

BOTTOM ASH COOLING SCREW

HOT LOW CALORIFICGAS (750 - 650 °C)

AIR PREHEATER

RET

UR

N L

EG

GASIFICATION AIR FAN

UNIFLOW CYCLONE

• Commercial lime-kiln gasifiers wereconstructed in 1980’s by Ahlström

• New development by Foster Wheelerin 1990’s for boiler applications

• Gasifiers are now offered by• Foster Wheeler• Carbona/Andritz• Metso Power

• Feasible in size range 15-150 MW

Source: Foster Wheeler

VTT’s role and activities• IPR on FB gasification• IPR on gas reforming for clean gasapplications

• support for industrial projects• R&D on gas filtration, heavy metalremoval and fuel characterisation

Atmospheric-pressure CFB/BFB gasificationfor kilns and boilers

5624/03/2011

The CFB test rig is used in R&D for:• Gasification of challenging fuels • Gas cooling and filtration • Heavy metal and chlorine removal• R&D in other high temperature processes

Feedstocks used in PDU-tests include:• Wood waste, straw, coal and peat• Mixed plastics, RDF, demolition wood and industrial waste feedstocks

Technical information:• Inside diameter: 0.15 m• Reactor height: 7.9 m• Temperature: 600 - 1000 °C • Gas velocity: 1 - 5 m/s • Pressure: 1 bar (abs) • Max. fuel feeding: 80 kg/h • Fuel capacity: 350 kW • Gas cleaning: cyclones, ceramic/bag filters,

catalytic decomposition

Additional informationEsa Kurkela, Development ManagerTel. +358 20 722 5596esa.kurkela@vtt.fi

Matti Nieminen, Customer ManagerTel. +358 20 722 6587matti.nieminen@vtt.fi

Atmospheric-pressure PDU-scale CFB-gasification test rig

BAG FILTER

COMBUSTOR& FLUE GAS SCRUBBER

Fabric bag filter: -16 bags (4x4)

- 110 x 1000 mmCeramic candle filter unit:- 12 x 1000 mm long candles (3 x 4 clusters)

CERAMIC

CANDLE

FILTER

5724/03/2011

This AFB60 test facility is used for preliminary gasification tests with new fuels before entering into larger-scale tests. The effects of gasification conditions on carbon conversion, ash behaviour and gas composition can be examined. In addition, this test rig is used for catalytical gas cleaning studies.

Test facility:• Gasifier• Ceramic filter• Catalyst/SCO-reactor

Technical information of gasifier:• Bed diameter: 63 mm• Freeboard ds:104 mm• Temperature: 600-1000 C• Fuel feeding: about 1 kg/h

Additional information

Esa Kurkela, Development ManagerTel. +358 20 722 5596esa.kurkela@vtt.fi

Jaana Laatikainen-Luntama,Research ScientistTel +358 20 722 5598 jaana.laatikainen-luntama@vtt.fi

Atmospheric-pressure fluidised-bed reactor for air-blown gasification

GASIFIER HEAT TREATMENT OF VAPOURS

Atmospheric fluidised-bed gasifier

Fuel feeder

Ceramicfilter

To gas combustor

Gas sampling

Gas samplingPrimary air

5824/03/2011

Proven reference: Lahti (Kymijärvi power plant), Finland

CFB gasifier of 60MW

Main boiler360 MWth

Gasifier feed preparation

- In operation since 1998- No commissioning problems- Gasifier availability > 95 %- Boiler emissions decrease

5924/03/2011

Experience from the Lahti no. 1 Plant

Very high availabilityVery flexible with respect to fuels (wood/wood waste, REF/SRF, waste plastics, waste paper/-cardboard, railway sleepers, sludge, etc.)Careful fuel control => almost all emissions lowered

Emission Change caused by gasifierNOx Decrease by 10 mg/MJ (= 5 to 10 %)SOx Decrease by 20 - 25 mg/MJHCl Increase by 5 mg/MJ CO No changeParticulates Decrease by 15 mg/m3nHeavy metals Slight increase in some elements, base level low

DioxinsFuransPAHBenzenesPhenols

No changeNo changeNo changeNo changeNo change

6024/03/2011

Gas cleaning: gas cooling followed by filtrationdeveloped at VTT since late 1990’s

Gascooler

Filter

Fuelfeeding

Gasburner

Coalburners

Bed material/Ca-basedadditive

Sorbent

6124/03/2011

0,0

10,0

20,0

30,0

40,0

50,0

60,0

70,0

80,0

90,0

100,0

Na K Cl Al Ca Hg Sn Sb As Cd Pb V Mn Co Ni Cu Zn Mo Cr Si Mg

% o

f out

put

Bottom ash Cyclone dust Filter dust Gas

Fuel: SRF (RDF); Ceramic fabric filter (3M FB-900); Cyclone temperature 700-750oC; filter temperature 395oC)

0,0

10,0

20,0

30,0

40,0

50,0

60,0

70,0

80,0

90,0

100,0

Na K Cl Al Ca Hg Sn Sb As Cd Pb V Mn Co Ni Cu Zn Mo Cr Si Mg

% o

f out

put

Bottom ash Cyclone dust Filter dust Gas

Fuel: SRF (RDF); Ceramic fabric filter (3M FB-900); Cyclone temperature 700-750oC; filter temperature 395oC)

VTT data from late 1990’s

6224/03/2011

LahtiStreams IP (Advanced Integrated Waste Management and WtE Demonstration)

( Lahti Energia/FI, VTT/FI, L&T/FI, Dong Energy/DK, FZK/D; total budget 23.5 M€)

- Demonstration of complete advanced waste management chain including: > waste processing> material recovery> SRD/RDF production> advanced high efficiency WtE plant> further treatment of ashes

-R&D of - waste processing and material recovery- improved hot gas cleaning- advanced ash treatment- new gasification based high efficiency WtE technologies

http://www.lahtistreams.com/

6324/03/2011

RFD

Gasifier Gas cooling

Gas cleaning

Gas boiler

High pressure steam

Electricity, process steam

Flue gas cleaning

Bag house, Ca(OH)2+ activated carbon

Steam turbine

Natural gas/ oilauxiliary fuel

Demonstration by Lahti Energia Oy (Lahti, Kymijärvi)- SRF fuelled gasification based WtE plant (CHP) - 2 x 80 MW th gasification & gas cleaning trains- 160 MW th gas fired boiler- Technology supplier: Metso

6424/03/2011

Source: T.Anttikoski, Foster Wheeler Energia Oy

Plastic reject materialwith 10 % aluminium

Corenso gasifier in Varkaus, Finland• gasification of aluminium containing plastic reject material• complete recycling of liquid cartoons (milk & juice packaging)• 50 MW gas to boiler, 2100 t/year aluminium for re-use• developed by VTT & Foster Wheeler Energia Oy in 1998 - 2000

in operation since autumn 2001

Source: Foster Wheeler

6524/03/2011

Power and Steam

Large Scale

6624/03/2011

Source: TECO Power services

Integrated Gasification Combined Cycle = IGCC

6724/03/2011

Large-scale Power with Integrated Gasification Combined-Cycle - IGCC

• Fluidised-Bed Gasification at 20 bar, 800-950 oC

• Gas filtration at 350-600 oC

• Combined Gas Turbine and Steam Turbine Process

Biomass IGCCDemonstration Plant,Värnamo, Sweden

• Developed and demonstrated in 1990’s• Electric efficiency 42 - 48 %• Requires large-scale > 50 MWe

• Best potential for CO2 reduction• Market situation in Finland and Swedenwas unfavourable in mid 1990’s - large scale projects were not realised

• Maybe times will be better forhigh-efficiency power in a near future?

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Coal

Oil

Biomass

Waste

SyngasH2+CO

Fuel gas

Gasification

&

Gas Cleaning Gas engineFuel cellGas turbineBurnerKiln

ChemicalsHydrogenSNGLiquid fuels

Carbon

Synthesis gas route"C1-Chemistry"

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History of the synthesis gas production

Commercialization of the cryogenic separation of air by Carl von Linde in the 1920sWinkler fluid-bed process (1926)Lurgi moving-bed pressurized gasification process (1931)Koppers-Totzek entrained-flow process (1940s)

Little further technological progress was made in the gasification of solid fuels over the following 40 years.

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History of the synthesis gas production

The capacity still expanded steadily:Germany’s wartime synthetic fuels program Worldwide development of the ammonia industry.Foundation of Sasol.

With the introduction of abundant resources of natural gas and naphtha in the 1950s, the importance of coal gasification declined.The need for synthesis gas, however, did not.

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Gasification capacity by product

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Relevant potential products from synthesis gas

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Syngas versus product gas

Product gas contains, along with the desired main components (H2, CO), also a large amount of impurities, out of which most are harmful for the synthesis phase and must be removedIn chemical syntheses, transition metal catalysts are used (Co, Rh, Pt, Ni…), that are poisoned very easily. Therefore low amounts of

SulphurTarCl, N and metals are needed

Gas should also contain only low amounts of fine-grained solids to avoid mechanical deactivationCH4, other paraffines and CO2 are often inerts

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Biomass gasification forliquid biofuels and green chemicals

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FUEL ROADMAPS AT THE END OF CHEAP OIL AGE

IEA’s BLUE Map scenario predicts 26 % biofuels in 2050 (ETP 2008)IEA’s BLUE Map scenario predicts 26 % biofuels in 2050 (ETP 2008)

84 mbd

Transportation -

Other Uses -

50 mbd

34 mbd

Transportation

World

Petroleumcomsumption

2008

A. Röj 2006

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Different approaches to BTL

• Biochemical routes to ethanol

• Different final products fromsyngas (FT-diesel, methanol,DME, gasoline, H2, CH4 …)

• Alternative biomass gasification processes

• Electric or hybrid cars withrenewable electricity

TRANSFORMATION THROUGHINTERMEDIATES(SUGARS)

REDUCTION TO BUILDING BLOCKS(CO, H2)

BIOCHEMICALCONVERSION

THERMO-CHEMICALCONVERSION

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Production and Conversion of Biomass-Derived Synthesis GasMain Steps in Overall Process

MainProduct

HP Steam

CO shift,H2S removalCO2 removal

MP Steam Off-gas

Heat

Typical pressures: 1 - 30 bar 30 bar 30 - 200 bar

Biomass

SteamSteam + O2

DRYINGGASIFICATIONREFORMING

INITIAL GAS CLEANING

SYNTHESIS/UPGRADING

FINAL GASCLEANING ANDCONDITIONING

Commercially available technology:

experiences from coal, oil and natural gas processing

Focus of R&D efforts at VTT:

Special technology for biomass

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What would mean e.g. 5 % of EU market?

EU MARKET – 2030: Huge need to be satisfied

15 Mtoe150 gasification-synthesis plants of 300 MW feedTurnover/year:100 M€/planttotal 15 billion €/yearInvestment potential:50 billion € in 2015-3015 plants/year at ca. 2020 => 5 B€/year

Biofuels Technology Platform SRA 2008Biofuels Technology Platform SRA 2008

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Production of Biomass-Derived Synthesis GasInitial step - two main approaches

Biomass Raw synthesis gas

to cooling, clean-up and conditioning

Typically: fluidised-bedgasifier, either oxygen-blownor indirectly heated

GASIFIER

e.g. 850 ºC

REFORMER

900 ºCcatalytic

Main technical challenge: reforming of gas

Biomass Raw synthesis gas

to cooling, clean-up and conditioning

Typically: oxygen-blown entrained-flow gasifier

DryPulverBIOMASS

PRE-TREATMENT

GASIFIER

1300 ºC +

Main technical challenge: prehandling, feeding of biomass

orPyrolysis

oil

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Entrained-Flow Gasifiers

Output > 100 MW th

Feedstock size < 0.1 mmCommercially available for coal and heavy oilGasification temperature 1300 - 1500 °C

Texaco, Shell, Prenflo

GAS

SLAG

FEEDSTOCK OXYGEN & STEAM

Not applicable as such to biomass;

• main problem: feeding

• examples of solutions:

• prior pyrolysis on site (Choren Carbo-V®)

• prior pyrolysis elsewhere (FZK-ITC concept)

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82

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From: Bienert, Warsow 29-31.8.2007

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From: Landälv, tcbiomass, 2009

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From: Landälv, tcbiomass, 2009

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87From: Landälv, tcbiomass, 2009

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Fluidised-Bed GasifiersOutput > 20 MWth

Feedstock size < 10 mmGas temperature 800 - 900 °C

CIRCULATING FLUIDISED BED (CFB)Fluidising velocity 3 - 10 m/sHigher output/diameterReactive feedstocks

BUBBLING FLUIDISED BED (BFB)Fluidising velocity 1 - 3 m/sLong residence time

Foster Wheeler Energia, Carbona/Andritz

FEEDSTOCK

AIR

ASH

GAS

Applicable to biomass, technologies for synthesis-gas applications in demonstration phase

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Forestry residues,mill residues,straw, energy crops,urban biowaste

Synthesis& upgrading

Gasification andgas treatment

Pulp andpaper mill

Biomasshandling

anddrying

powerplantProcess steam & power

Paperor pulp

Hydrocarbon fuels (FT)(or methanol, SNG, H2, etc.)

Energyto drying

synthesis-gas

bark,forestryresidues,otherbiomass

fuel gas+ steam

steam & oxygen

Syngas Route to Biofuels – Integrated Concept

150-300 MW

75-160 MW

50-150 MW

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Moistfeedstock Dryer Gasifier Reforming

Heat

Oxygen

Recycle gas

Oxygenplant

HPSteam

HTShift

LPSteam

HPSteam

CombustorHP Steam

Scrubber-cooler

RegenerativeAbsorber FT synthesis

FT primary liquids (C5+)

LP Steam

FT reforming loop

FT off-gas (purge)

H2O

MP Steam

SeparatorCW

CW

Steam

Process Scheme for Production of FT Liquids

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Efficiencies with Industrial-Heat ProductionEfficiency = 100 x [LHV-energy of main product + high-grade byproduct energy – {electricity / 0.4}]

/ [LHV-energy of as-received feedstock]

Feedstock drying: from 50 % moisture to 30 % with secondary heat; from 30 % to 15 % with by-product steam

From: McKeough & Kurkela, NWBC, Stockholm 2008

-40

-20

0

20

40

60

80

100

FT CH3OH SNG H2

Ove

rall

Effic

ienc

y, %

Primaryenergy outMain product

(Electricity in)/ 0.4

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92

SYNGAS FROM PEAT AND WOODHTW-PLANT AT OULU KEMIRA AMMONIA PLANT, 120 MWfuel, (operation in 1989-90)

HTW gasifier

Peat crushmoisture 15 %

SteamOxygen Recycle gas

Wasteheat

boiler

Steam

Waterscrubber

Dust

Ash

Gas to amisol scrubber1500 k mol/h 29 bar

Sludge separation

Peat from MoDosteam dryer

Benzenescrubber

To naphthaleneextraction

Benzene fromnaphthaleneextraction

10bar750-

950°C

Pressurised steam/O2-blown gasifier

• Technology was successfully demonstratedin late 1980’s with peat and lignite(Oulu, Berrenrath)

• Single gasifier train 150-300 MW feasible

Improvements to the process:• HTW gasifier replaced by CFB

- fuel flexibility, high availability- operation at lower temperature

• New gas cooler design- not sensitive to fouling

• Hot filtration instead of wet scrubbing of particulates

• Reforming of hydrocarbons- elimination of tar problem - higher syngas yield- higher H2/CO ratio

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The Finnish Development Plandeveloped in VTT’s UCG project in 2004-2007

Initial R&D project: budget ca. 4 MEUR, duration 1.1.2004 – 31.5.2007

Industrial consortium: Foster-Wheeler, Neste Oil, Andritz, Vapo, PVO, UPM, M-real, Metsä-Botnia, Stora-Enso

0.5 MW process development unit (PDU); operated by VTT's Gasification Research Group

Demonstration of bio-syngas process planned for the period 2008 – 2010size of demonstration plant: 10 – 50 MW feedstock inputoperation of plant to be economically profitable: replacement of natural gas or fuel oil; parallel experimental program on the flexible PDU unit at VTTplant design studies already under way

The subsequent step: pre-commercial plant; 250 MW; commissioning 2013

Acknowledgement of funding sources: the National Technology Agency of Finland (Tekes), VTT and the companies of the consortium (above)

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Gasification and Gas Cleaning ProcessDeveloped and tested at VTT on 0.5 MW scale

GAS CLEANING• TAR & METHANE

REFORMING• FILTRATION• DIRTY SHIFT

NEW INNOVATIVE TECHNOLOGYFT-DIESEL

CH3OH

ULTRA CLEANUP

HYDROGENSNG

CELLS

CLEAN FUELGAS TO FUEL

CELLS

FUEL-FLEXIBLECFB

GASIFICATION• STEAM/OXYGEN• PRESSURISED

GASIFIER TARGETS• NO ASH-RELATED PROBLEMS• SIMPLE DESIGN AND HIGH RELIABILITY• HIGH C-CONVERSION TO GAS+TARS• LOW OXYGEN CONSUMPTION

GAS CLEANING TARGETS• COMPLETE TAR DECOMPOSITION• OVER 80% METHANE REFORMING• H2/CO RATIO SUITABLE TO FT-SYNTHESIS

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Gasification and Gas Cleaning ProcessDeveloped and tested at VTT on 0.5 MW scale

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VTT-UCGOPTIMISED

SYNGAS R&D& PDU-SCALE

TESTING

INDUSTRIAL R&D& DEMONSTRATION• REPLACEMENT OF OIL• START-UP IN 2009

FURTHER R&D• PROCESS OPTIMISATION• WASTE GASIFICATION• HYDROGEN TECHNOLOGIES

NEW APPLICATIONS• FUEL CELLS, 2nd GEN. IGCC• HYDROGEN OR METHANE• RENEWABLE CHEMICALS

R & D ON HOTFILTRATION AND

CATALYTIC GAS CLEANING

BIOMASS/WASTE GASIFICATION FOR POWER

(LAHTI, CORENSO,VÄRNAMO)

PEATAMMONIA

PLANTOULU/FINLAND

SYNTHESIS GASR&D IN EUROPEAND USA IN 1980’s

FIRST SYNFUEL PRODUCTION PLANT• 200-250 MW FEED CAPACITY• 105 000 tons/a DIESEL FUEL• 2-3 % FINNISH TRANSPORT FUEL• START-UP IN 2012-14

1995 2000 2005 2010 2015 20201985 2025 2030

BIOREFINERIES AT PULP AND PAPER MILLS AND AT LARGE CHP PLANTS• FUEL PRODUCTION: 70-150 000 tons/plants• BY-PRODUCT HEAT FOR PROCESS STEAM ORDISTRICT HEATING

• HIGH OVERALL EFFICIENCY

SYNTHESIS GAS FROM BIOMASSFROM R&D TO INDUSTRIAL SUCCESS(road map generated in VTT:s UCG project in 2006)

VTT-UCGOPTIMISED

SYNGAS R&D& PDU-SCALE

TESTING

INDUSTRIAL R&D& DEMONSTRATION• REPLACEMENT OF OIL• START-UP IN 2009

FURTHER R&D• PROCESS OPTIMISATION• WASTE GASIFICATION• HYDROGEN TECHNOLOGIES

NEW APPLICATIONS• FUEL CELLS, 2nd GEN. IGCC• HYDROGEN OR METHANE• RENEWABLE CHEMICALS

R & D ON HOTFILTRATION AND

CATALYTIC GAS CLEANING

BIOMASS/WASTE GASIFICATION FOR POWER

(LAHTI, CORENSO,VÄRNAMO)

PEATAMMONIA

PLANTOULU/FINLAND

SYNTHESIS GASR&D IN EUROPEAND USA IN 1980’s

FIRST SYNFUEL PRODUCTION PLANT• 200-250 MW FEED CAPACITY• 105 000 tons/a DIESEL FUEL• 2-3 % FINNISH TRANSPORT FUEL• START-UP IN 2012-14

1995 2000 2005 2010 2015 202019851985 2025 2030

BIOREFINERIES AT PULP AND PAPER MILLS AND AT LARGE CHP PLANTS• FUEL PRODUCTION: 70-150 000 tons/plants• BY-PRODUCT HEAT FOR PROCESS STEAM ORDISTRICT HEATING

• HIGH OVERALL EFFICIENCY

SYNTHESIS GAS FROM BIOMASSFROM R&D TO INDUSTRIAL SUCCESS(road map generated in VTT:s UCG project in 2006)

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• National UCG project: budget 4 MEUR, duration 2004 – 2007

Biomass gasification and gas reforming experiments employing the 0.5 MW process development unit PDU at VTT

Wide industrial consortium: Foster-Wheeler, Neste Oil, Andritz-Carbona, Vapo, PVO, UPM, M-real, Metsä-Botnia, Stora-Enso

• Demonstration phase now under way:

Demonstration plant in operation at Varkaus, Finland; consortium: Neste Oil and Stora-Enso

The Finnish Development Path – NSE Biofuels

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NSE Biofuels Demo 1 plant in Varkaus, Finland

From Neste Oil and Stora Enso

1. Commissioning as air blown limekiln gasifier

2. Testing period as O2/H2O gasifier,gas cleaning, FT tests

3. Return to lime kiln gasifier

Limekiln

5 MWGas cleaning

and FT

BiomassSiloKuivuriDryer 12 MW

Gasifier

1. Commissioning as air blown limekiln gasifier

2. Testing period as O2/H2O gasifier,gas cleaning, FT tests

3. Return to lime kiln gasifier

Limekiln

5 MWGas cleaning

and FT

BiomassSiloKuivuriDryer 12 MW

Gasifier

Limekiln

5 MWGas cleaning

and FT

BiomassSiloKuivuriDryer 12 MW

Gasifier

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Stora Enso / Neste Oil Joint Venture for F-T BTL Diesel Fuel

50/50 Joint Venture “NSE Biofuels Oy” to first develop technology and later produce next generation renewable diesel crude from wood / forest residues

Currently building a 12MW demonstration plant in Stora Enso’s Varkaus mill, to be in use spring 2009

Investment decision for a commercial scale plant when the parties have enough experience from the demonstration plant

Strong development consortiumJoint Venture partners:Testing & research partner:Gasification supplier: From Neste Oil and Stora Enso

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PRESSURISED GASIFICATION OF BIOMASSVärnamo IGCC Demonstration

Plant at 1990’s

FW scope: Gasification plant

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The Finnish Development Path - UPM

• National UCG project: budget 4 MEUR, duration 2004 – 2007

Biomass gasification and gas reforming experiments employing the 0.5 MW process development unit (PDU) at VTT

Wide industrial consortium: Foster-Wheeler, Neste Oil, Andritz-Carbona, Vapo, PVO, UPM, M-real, Metsä-Botnia, Stora-Enso

• Demonstration phase now under way:

Demonstration plant in operation at Varkaus, Finland; consortium: Neste Oil and Stora-Enso

Pilot-plant testing at Gas Technology Institute, Chicago, USA; consortium: UPM and Carbona

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International Gasification R&D Cooperation

CARBONA with

The Gas Technology InstituteChicago, USA

• long term exclusive cooperation• pressurized BFB gasification• biomass fuels• air and oxygen gasification• gas cleanup systems• for IGCC and BTL

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Critical R&D issues of biomass gasification• Ash behaviour and fuel reactivity of different biomass feedstocks withrespect to different gasification processes (limits for real fuel flexibility)

• Removal of particulates, alkali-metals and chlorine by hot filtration(fundamental R&D, industrial-scale design and operation experience)

• Formation and behaviour of tars in gasifiers, gas coolers and filtration(still a long way to fundamental understanding)

• Removal of tars and ammonia by catalytic high-temperature systemsor by advanced wet scrubbing (industrial experiences & further R&D)

• High-quality process simulation and system analysis fordifferent gasification applications (international co-operation)

• Robust on-line analytics from R&D labs to industrial gasification plants (rapid tar analysis developed by VTT, robust sampling lines & analysers needed)

Fundamental gasification R&D in 2008-2010

VTT, TKK and Åbo Akademi, total budget 1.5 M€Financing by Tekes Biorefine, VTT and private companies(Carbona, Foster Wheeler, Metso Power, Neste Oil, Stora Enso, UPM, Vapo & Gasum)

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GASIFICATION800 - 1400 oC

GAS

CLEANING

COAL

OIL

BIOMASS

WASTE/SRF

O2

AIR

STEAM

SYNGAS(CO + H2)

FUEL GAS

Industrial kilnsCo-firing in boilersGas turbinesEnginesFuel cells

FT-diesel fuelMethanol, DMEGasoline, jet-fuelHydrogenSynthetic methaneChemicals

Biomass Gasification to Different Final Products

High-QualityFinal

Products

WideFeedstock

basis

10524/03/2011

VTT creates business from technology