Foster Wheeler Atmospheric Gasification Technology:

Development and Latest ExperiencesBrief Summary

Matti HiltunenFoster Wheeler Energia Oy

Finland

TopicsRome, Palazzo dei Congressi, May 10, 2004

• Update of recent projects

– Lahti plant, Finland

– Corenso plant, Finland

– Ruien plant, Belgium

• Gasification of recycled fuels

– Clean gas production

– Lahti Slip Stream Tests

Lahti Gasification PlantRome, Palazzo dei Congressi, May 10, 2004

Rome, Palazzo dei Congressi, May 10, 2004

Lahti Fuels

Lahti Operating Experiences 1998-2003Rome, Palazzo dei Congressi, May 10, 2004

• Operation of the gasifier and the gas burners has been stable• Stability of the steam cycle and coal burners good• No deposit formation or high temperature corrosion observed on the heat transfer surfaces

• Operating data 1998 - 2002– Operating time 27 000 hours– Energy produced 1700 GWh– Fuels gasified 498 000 ton– Availability of the gasifier 97.5 %

Gasifier Effect to Main Boiler Emissions Rome, Palazzo dei Congressi, May 10, 2004

NOx Decrease by 10 mg/MJ (= 5 to 10 %)SOx Decrease by 20 - 25 mg/MJCO No changeHCl Increase by 5 mg/MJ , base level lowParticulates Decrease by 15 mg/m3nHeavy metals Increase in some elements, base level lowDioxins, etc. No change

Corenso Design Rome, Palazzo dei Congressi, May 10, 2004

Original designGasifier Boiler40 MW 40 MW product gas

68 MW HFO

Reject consumption 18 000 ton/aEnergy produced 165 GWh/aSubstituting 16 500 ton HFO/aAluminium recovered 2 100 ton/a

Increased effectThe effect of the gasifier was increased to 50MW.

Rome, Palazzo dei Congressi, May 10, 2004

Corenso FuelRome, Palazzo dei Congressi, May 10, 2004

Corenso Operating ExperienceRome, Palazzo dei Congressi, May 10, 2004

• Commercial operation since autumn 2001• Operating hours appr. 12 500 h • Feeding of light reject into dense fluidized bed• Aluminium handling: operating windows are ensured• FW spring hammers as a solution to keep the furnace clean• Cl emissions in control• Availability equal to normal power plant availabilities

Ruien DesignRome, Palazzo dei Congressi, May 10, 2004

• Biomass gasifier producing “green electricity” in co-combustion with coal in an existing PC boiler

• Using of renewable fuels to cut CO2 emissions

• Design 50 MWth with 50 % fuel moisture (86 MWth with 20 % fuel moisture)

• Electric efficiency 34 % (Boiler 36 %, gasifier 98 %)

• Produced “green” electricity 17 MWe

• Annual production 120 GWh

Ruien GasifierRome, Palazzo dei Congressi, May 10, 2004

RUIEN

BRYSSEL

Ruien FuelsRome, Palazzo dei Congressi, May 10, 2004

• Bark• Demolition wood

• Crushed wood based boards, chip boards, etc.

• Moisture 25-30 %

Ruien Process PerformanceRome, Palazzo dei Congressi, May 10, 2004

The gasifier in operation since May 2003

Environmental benefits– NOx & SOx reduced– CO & dust emission about the same or slightly reduced– Trace metals & dioxins no change– CO2 reduction 120.000 t/a, substituting of coal 50.000 t/a

Clean Gas ConceptRome, Palazzo dei Congressi, May 10, 2004

Main boiler feed water

Main boiler furnace

Recycled fuels

CFB Gasifier

Pulsing gas

Cooling water

Flare

LP Steam

Filters

Fly ash

Bed materials

Gas cooler boiler

Fuel feed system

Lahti Slip Stream TestsRome, Palazzo dei Congressi, May 10, 2004

• To demonstrate the performance of the Clean Gas Concept, a long term product gas cooling and filtration tests including product gas combustion tests for different fuel mixtures was arranged

• Connected to the commercial 70 MWth CFB gasifier in Lahti firing a blend of wood and wastes

• In the slip stream plant 5% of the syngas produced in the CFB gasifier was cooled and filtered

• The long term testing was stopped in April 2004, after more than 3300 hours of operation.

Lahti Slip Stream TestsRome, Palazzo dei Congressi, May 10, 2004

Pulsing N2

Sorbent feeder

Syn

gas

duct

from

gas

ifier

Syngas cooler

Filter

Syngas combustor

LLV Slip stream unit

Combustion air

Ash discharge systems

Filter by-pass line

Lahti Slip Stream TestsRome, Palazzo dei Congressi, May 10, 2004

In the Lahti slip stream tests it was demonstrated that

• By cleaning the waste derived product gas before the boiler, the amount of harmful components in the gas (heavy metals, alkalies, chlorine, dust, etc.) can be reduced significantly.

• The cleaned product gas can be safely burned in a high efficiency boiler with high steam temperatures

• The combustion of the cleaned gas was also environmentally safe: e.g.the emissions of heavy metals and dioxines were clearly below the WID limits