gasifiers

Biomass specialisation course

Review of Gasification Plants

Jesús Arauzo, Alberto Gonzalo, José L. Sánchez ([email protected])

Chem.&Environ. Eng. Dpt.

C.P.S.

www.cps.unizar.es/~proter

Gasification Plants

Configuration of a gasification plant depends on:- Fuel to be used- Type of reactor:

- fixed/moving bed- fluidized bed- entrained flow- combination

- Operation pressure (near atmospheric or pressurired)- Method to deliver the heat needed for reaction- End use of producer gas gas cleanup

There are so many different configurations possible, that it is difficult to find two similar plants in the world

Gasification Plants

Review of some of the most representative plants/projects,sorted by the kind of reactor used:

- Fixed bed gasifiersUpdraftDowndraft

- Fluidized bed gasifiersBubbling FBCirculating FB

- Entrained bed gasifiers- “Special” Plants with a combination of reactors:

Compact Power processCarbo V process

Gasification PlantsFixed Bed

FB UPDRAFT GASIFICATION

Babcock & Wilcox Vølund ApS

Put into operation in 1993, in the city ofHarboøre, to supply heat to 560 homesand municipal buildings.Fuelled by wood chips.Initially the producer gas was burnt in aboiler.After several years of research on gascleaning, in 2000 two 750 kWe Jenbachergas engines were set in operation



OIL/TAR FUELLED DISTRICT HEATING BOILER

UPDRAFT WOOD GASIFIER





FUEL AND ASH HANDLING SYSTEM

PRODUCER GAS FIRED DISTRICT HEATING BOILER





GAS CLEANING SYSTEM



HEAVY TAR SEPARATION SYSTEM



GAS ENGINES



TARWATC (FINAL WATER CLEAN UP)




FB DOWNDRAFT GASIFICATION

Combined Cycle Heat and Power PlantProject TU Bergakademie Freiberg

PPS Pipeline Systems GmbH

The technology is result of the research at the TU Bergakademie Freiberg in

cooperation with the Institute forInternational Forestry and WoodManagement at the TU Dresden


Project TU Bergakademie Freiberg - PPS Pipeline Systems GmbH

Based on a IGCC conceptProducer gas is burned in a combustionchamberCombustion flue gas is used in a hightemperature heat exchanger to heatfresh air, which is used to move thegas turbineThus, gas cleaning and the technicalrisk for gas turbine operation are mi-nimised





Clean wood consumed: 2500 kg/hHeating value of wood: 13.6 MJ/kgHeating value of producer gas: 5 MJ/kgCombustion chamber temperature: 980ºCHot air temperature: 800ºCGas turbine power generation: 1.3 MWSteam turbine power generation: 0.7-1 MWHeat output: 4.5 MW

Gasification PlantsFluidized Bed

BUBBLING FLUIDIZED BED GASIFICATION

Plastics Gasification Plant Poligas Ambiente

Biosyn Technolgy developed byKemestrie (spinoff company of theUniversity of Sherbrook, Canada)The plant is located in Ribesalbes (Castellón).Gasifies 15000 ton/year of plastic residues from the ceramic industry



Gasifier feed rate: 3000 kg/hRaw material: PE and PP residuesStart-up finished at the end of 2002Gasifying medium: O2-enriched air (40% O2)Fuel gas composition:

30-55% N2

16-30% CO2

12-30% CO2-10% H2

Gas HHV: 12 MJ/Nm3

8.4 MWe are generated by 11 760-kWe Jenbacher EnginesSolid residues are vitrified with natural gas






CIRCULATING FLUIDIZED BED GASIFICATION

Atmospheric air CGB gasification for heat production:Lahti Gasifier at Kymijärvi CHP Power Plant

Pressurised air IGCC producing hot fuel gas:Sydkraft Project at Värmano

Atmospheric air IGCC producing cold fuel gas:ARable Biomass Renewable Energy (ARBRE)

Dual bed atmospheric steam IGCC:FERCO-Silvagas plant at Vermont


Atmospheric air gasification in CFB for heat production:Lahti Gasifier at Kymijärvi CHP Power Plant

The plant is located near the city of Lahti (Finland)The 350 MW power plant runs on pulverized coal combustionThe 60 MWth gasifier was added in 1998, suppliedby Foster Wheeler Energia OyFuelled by: waste wood, packaging wastes,tyres, forest residues, replacing 15% offossil fuelProducer gas is fed into the coal boiler,to produce heat and steamInvestment of 14 M€


Lahti Gasifier at Kymijärvi CHP Power Plant


Lahti Gasifier at Kymijärvi CHP Power Plant

Gas composition (at 50% feed moisture):CO2 – 12.9%H2 – 5.9%N2 – 40.2%CO – 4.6%CxHy – 3.4%H2O – 33%LHV – 2.2 MJ/Nm3

Pressurised air IGCC producing hot fuel gas: Sydkraft Project at Värmano


The plant was built between 1991 and 1993.Demonstration programme concluded in October 1999First IGCC installation which worked at near commercial scaleThe plant run on gasifying operationfor more than 8500 hours and thegas turbine run on producer gasfor more that 3600 hoursFuels tested include:

barkWood chipsSalixStrawRDF

Sydkraft Project at Värmano


- The gasification technology hasbeen developed in cooperationbetween Sydkraft AB and FosterWheeler Energy International- The gas turbine was supplied by Alstom Power, with an electricaloutput of 4.2 MWe. A steam turbine produces 1.8 MWe- Thermal output 9 MWth- Biomass feed rate: 4300 kg/h- Air flow rate: 6500 kg/h- Pressure of operation: 18-22 bar- Hot gas cleaning system to avoidtar condensation



Feeding a mixture of bark, logging residues & waste woodat 5-25% moisture content:LHV of 18,9 MJ/kg.Carbon conversion in the gasifier: 97-98%.Gas LHV: 4.2-4.6 MJ/kg (does not include benzene and tar content)Gas composition (% in volume):

H2 - 11 %

CO - 16 %CO2 -12 %

CH4 -5 %

H2O - 12 %

N2 - 44 %

1300-1700 ppm NH3 , 9000 mg/m3 benzene, 3500 mg/m3 light tar,

500 mg/m3 heavy tarAsh from the cyclone: 15-20% de unburned carbon and 65-75% bed materialAsh from the bed: 0,2-0,5 % UC and 75-80% BM.



Atmospheric air IGCC producing cool fuel gas: ARBRE Project


The gasifier is an atmospheric pressure, air-blown circulating fluidizedbed system, developed by TPS of Sweden Construction began in 1998Feed material: wood (from conventional forestry and short-rotationplantation sites)Electrical output of 8 MWe,overall electrical eficiencyof 31%Cool clean producer gasis compressed to feed thegas turbine

ARBRE ProjectGasification PlantsFluidized Bed


Dual circulating fluid bed steam gasification:FERCO-SilvaGas™ Process Plant at Vermont

The SilvaGas process was developed by Batelle´s ColumbusLaboratories in 1970’s-80’sFuture Energy Corporation (FERCO) comercialices and has furtherdepeloped the technologyAfter more than 20000 hours of gasifying experience in a Process Research Unit (PRU) of 10 ton per day, FERCO constructed a 200 ton/d plant, located at BurlingtonElectric’s McNeil Power Station in VermontIn a first phase, producer gas was burned inthe station boiler .In a second phase, gas is cleaned and com-pressed in a gas turbine


FERCO-SilvaGas™ Process Plant at Vermont

Gasification is carried out in two CFB:

Steam is the fluiding/gasifying agent of the CFB where biomass is fedSolids (sand +char) entrained fromthis bed are transported to the 2ndCFB where the char is combustedwith air, producing the heat tocarry out gasification.

Hot sand from this bed is transportedto the 1st CFB, acting as the heatCarrier.

The advantage of the process isproducing a medium heating valuegas, as the product gas is not dilutedwith nitrogen from the air



Gasifier temperature: 800-850ºCGas heating value: 11-14 MJ/Nm3

Gas composition:



Gas cleaning includes a catalytic FB cracking, scrubbing andfinal refining in a wet ESP.

Gasification PlantsEntrained Bed

ENTRAINED BED GASIFICATIONSVZ Schwarze Pumpe waste gasification plant

Originally, SVZ produced town gas from lignite.Since 1995 SVZ gasifies different residues (plastics, contaminatedwood, sewage sludge, shredded materials from automovile recycling,MSW, waste oil, tar, …) with a total capacity of 560000 ton/y

Three types of reactors:Entrained flowUD with solid dischargeBGL (UD with moltendischarge of ash)


SVZ Schwarze Pumpe waste gasification plant



Feed material: liquid wastes

Reaction temperature: 1600-1800ºC

Capacity: 15 ton/h

Gasifying agent: O2 and steam

CO and H2 are the main gas products



Feed material: solid wastes

Reaction temperature: 800-1300ºC

Operation pressure: 25 bar

Capacity: 12 ton/h





Feed material: solid and liquid wastes

Reaction temperature: 1600ºC

Operation pressure: 25 bar

Capacity: 35 ton/h



Synthesis gas is used for methanol (120000 ton/y) and powerproduction (75 MWe gas/steam turbine)



Gasification Plants

Special plants, with a combination of different reactors:

Carbo V process: pyrolysis + thermal cracking + char gasification

Ebara-Ube process: FB + Entrained flow

Compact Power process: pyrolysis + UD char gasification + combustion

Gasification PlantsCarbo V process

CARBO V PROCESS

CHOREN Industries

A 1 MWth pilot unit was constructed at the Freiberg (Germany), commissioned in 1998. The process has been tested with a variety of feed materials over a period of 3 years and ran for a total of 5,000 hours.

The feed material includes: coal, sewage sludge, wood, ...

Carbo V process Gasification Plants

The Carbo-V Process is a three-stage gasification process incorporating the following steps:

- Low temperature gasification. working between 400ºC-600ºC.- High temperature gasification. Temperatures between 1300ºC and 1500ºC.- Endothermic entrained bed gasification. The temperature drops from more than 1,300 °C to 800 °C in a matter of seconds as a result of endothermic reactions.


The capacity of the pilot unit in Freiberg is 1 MWth.

A 150 kW gas engine from the Caterpillar company was installed in 2001 and was operated and optimized for a total of more than 600 hours.


Special Plants

ENTRAINED FLOW GASIFICATION

Gasification Plants

EBARA-UBE Process

Placed in Yamaguchi (south of Japan).Completion date: 30 November 1999. Since this date the plant has been working for 3500 hours.

Gasification Plants

The EBARA-UBE is a process of two-stage gasification under pressure.- Preparation of plastic: The plastics are compressed and molted (50 to 100 mm diameter, 100 to 200 mm length).- Low temperature gasification: 600ºC-800ºC.- High temperature partial oxidization of gas from low temperature gasifier.

Special Plants

Gasification Plants

Raw material: Waste plasticsPCS: 9000 kcal/kg.Plant capacity: 30 Ton/d (as waste plastic). They are building a 240 Ton/day plant. Product: 3500 Nm3/h of gas,Equivalent to 26 ton/d NH3 Hydrogen in gas is 49.9 vol%.By-product: Ammonium Cloride 1Ton/day.Gas composition:

H2 – 49.9 %CO – 33.6 %CO2 – 15.2%H2S – 2.3 %

Special Plants

Gasification PlantsSpecial Plants

Compact Power Process Gasification Plants

COMPACT POWER PROCESS

Compact Power is a British company which has developeda three-stage process to valorize difficult wastes (as clinical wastes

The stages are:Rotary kiln pyrolysisUpdraft gasificationHigh temperature combustion

Valorization is performedthrough a steam cycle

Compact Power Process Gasification Plants

COMPACT POWER PROCESS

Biomass specialisation course

Review of Gasification Plants

Jesús Arauzo, Alberto Gonzalo, José L. Sánchez ([email protected])

Chem.&Environ. Eng. Dpt.

C.P.S.

www.cps.unizar.es/~proter

gasifiers

Documents

gas turbine operation

igcc conceptproducer

cgas turbine power generation

wood chips

kghheating value of

operation pressure

hightemperature heat

chot air temperature