Experiences from the Lahti and Ruien Plants. 25 th of May 2005 Timo Anttikoski Foster Wheeler Energia Oy

Transcription

1 Experiences from the Lahti and Ruien Plants 25 th of May 2005 Timo Anttikoski Foster Wheeler Energia Oy

2 Foster Wheeler Global Power Group Products Complete boiler islands/power plants - EPC deliveries Circulating fluidized bed (CFB) boilers - Up to 600 MWe, all solid fuels Bubbling fluidized bed (BFB) boilers - Up to 100 MWe, biomass, & other high volatile fuels Pulverized coal-fired (PC) boilers - Up to 1,000 MWe Atmospheric CFB gasifiers Heat recovery steam generators (HRSGs) - For gas turbines up to 250 MWe Waste heat boilers (WHBs) - For metallurgical and waste incinerating processes Package boilers Condensers and heat exchangers Service - Repairs and spare parts - Boiler modifications - Process improvements - Emergency service - Coal mills, burners - Environmental retrofits (BFB, SCR, SNCR, etc.) - OM&S agreements

3 The world leader in fluidized bed boiler technology Over 40 years experience in fluidized bed combustion First BFB boilers delivered in the 1970s, based on work started in the 1960s World s first CFB for power generation supplied in 1979; second-generation technology in 1992 World s first once-through supercritical CFB project won in 2003 Benefits: simple construction, reliable, excellent efficiency and availability, multifuel capability Meets tough emission regulations without additional flue gas cleaning systems 227 CFB BOILERS DELIVERED TO DATE 202 in operation 25 under construction Largest unit currently in operation: 300 MWe Largest unit contracted: 460 MWe EC Chorzów Elcho

4 Foster Wheeler Gasifier Concept

5 Foster Wheeler Atmospheric CFB/BFB Gasification Developed in the end of 1970 s - in the beginning of 1980 s Driving force the dramatical increase in oil price First commercial applications produced gas for lime kilns (4 units) Foster Wheeler has supplied 7 commercial scale CFB/BFB gasifiers producing low heat value gas for different applications

6 Foster Wheeler Atmospheric Gasifier References Customer MW Fuel Application Year Hans Ahlstrom Laboratory, Finland 3 Misc. Test unit 1981 Oy W. Schauman Ab, Finland 35 Bark, sawdust Lime kiln fuel 1983 Norrsundet Bruks Ab, Sweden 25 Bark Lime kiln fuel 1984 ASSI Karlsborg, Sweden 27 Bark Lime kiln fuel 1984 Portucel, Rodao, Portugal 15 Bark Lime kiln fuel 1985 Kemira Oy, Vuorikemia, Finland 4 Coal, peat Test unit, clean gas 1986 Lahden Lämpövoima Oy, Finland Biofuels Hot raw gas to boiler 1997 Corenso United Ltd., Finland 40 Cyclone cleaned Aluminious plastic waste gas to boiler 2000 Electrabel, Belgium 50 Biofuels Hot raw gas to boiler 2002

7 Foster Wheeler CFB Gasifier REACTOR UNIFLOW CYCLONE 850 C GASIFICATION AIR FAN BIOFUEL FEED 900 C RETURN LEG AIR PREHEATER COOLING WATER HOT LOW CALORIFIC GAS ( C) BOTTOM ASH COOLING SCREW BOTTOM ASH

8 Status of FW Fluidized Bed Gasification Concepts Gasification combustion of raw product gas NEW: gasification + gas cooling and filtration combustion of clean product gas Energy production Co-combustion of raw gas / clean gas in existing PC boiler NEW: stand alone plant with steam turbine island Size of gasifier Raw gas MW fuel Clean gas MW fuel References Lahti Energia MW (raw gas, co-firing) Corenso Varkaus 50 MW (raw gas, stand alone) Electrabel Ruien, Belgia 50 MW (raw gas, co-firing)

9 Fuels Used in FW CFB Gasifiers Fuel: Wood, bark, chips, saw dust REF, plastics, (RDF) Coal, straw, peat, RDF ASR (Automotive Shredder Residue), other special wastes Status: Commercial Commercial Demonstrated Under development

10 References Lahti & Ruien

11 Power Station Kymijärvi, Lahti Finland BIOFUEL PREPARATION PLANT MAIN BOILER (OLD PC BOILER) GASIFIER COAL YARD COAL BUNKERS & MILLS

12 Lahti Gasifier Process 360 MW 540 C/170 bar Biomass 350 GWh/a -15 % fuel input Processing 50 MW Pulverized coal flames Power * 600 GWh/a District Heat * 1000 GWh/a Gasifier Gas flame Bottom ash Coal Natural Gas 1850 GWh/a -80 % 100 GWh/a -5 % Fly ash

13 Lahti Gasifier

14 RUIEN PROCESS 540 MW 540 C/180 bar Biomass ton/year CO 2 Reduction ton Processing 50 MW Pulverized coal flames Gasifier Gas flame Bottom ash Coal ton/year Fly ash

15 Electrabel Ruien Gasifier

16 Electrabel Ruien Gasifier

17 Ruien Design 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

18 RUIEN GASIFIER REACTOR

19 RUIEN CYCLONE

20 RUIEN GASIFIER REACTOR

21 RUIEN, AIRHEATER

22 RUIEN, PRODUCT GAS BURNER

23 Experiences from Lahti & Ruien

24 Lahti fuels

25 Lahti fuel conveyor

26 Lahti Fuels 100 % 80 % 60 % 40 % 20 % 0 % GWh GWh GWh GWh GWh GWh Rlw. Sleepers Tires Paper Plastic REF Wood w. glue Wood YEAR

27 LAHTI OPERATIONAL EXPERIENCES Stable operation of the Gasifier and Gas Burners Coal combustion in the main boiler has not been disturbed by the gasifier No additional fouling or corrosion in the main boiler has been noticed compared to coal combustion Main boiler fly ash composition and utilization has not been changed Main boiler availability has not been worsened by the Gasifier

28 Gasifier Effects To Main Boiler Emissions NOx Decrease 10 mg/mj (= %) SOx CO HCl Particles Heavy metals Dioxines Decrease mg/mj No change Increase 5 mg/mj, base level low Decrease 15 mg/m3n Slight increase, base level low No change

29 Ruien Fuels Bark Demolition wood Crushed wood based boards, chip boards, etc. Moisture %

30 Ruien Process Performance 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 t/a, substituting of coal t/a

31 RUIEN, GASIFIER CAPACITY Heats to the boiler MW Moisture of the fuel % Carbon dust Gas sensible Gas chemical

32 Lahti & Ruien Summary

33 Gasifier - PC Boiler Combustion Offers Lower environmental emissions use of coal is reduced => lower CO2, SO2 and NOx emissions Better fuel flexibility Possibility to use local fuel (biomass, REF, plastics, etc.) resources in high efficiency steam cycle Low investment and operation costs Utilization of existing power plant capacity Only small modifications to the main boiler High plant availability: If problems in the gasification system, still possible to get full output from the main boiler

34 Future gasifier concepts

35 Clean Gas Concept for REF/RDF Recycled fuels Fuel feed system Bed materials Gas cooler Main boiler feed water Pulsing gas Flare CFB Gasifier Filters Main boiler furnace LP Steam Cooling water Fly ash

36 Power Production Efficiency in Clean Gas Co-Combustion Concept CHP plant: Waste to power % Condensing power plant: Waste to power % Gasifier Vantaa, Vantaan Energia Vaasa, Vaskiluodon voima

37 Clean Gas Concept & CO-Combustion in PC Boiler Offers Possibility to utilize waste fuels in existing PC boilers To replace coal => CO2 Reduction To utilize high steam parametres => High electrical power production Utilization of the existing boiler & turbine => Significantly lower investment costs compared to stand alone waste incineration plant Effective emission control => Effective chlorine and heavy metal removal, effective combustion in the PC boiler furnace, no dioxine formation, utilization of the existing PC boiler flue gas treatment, coal ash and waste ash will be separated from each others

38 Stand Alone Gasification Plant for RDF Additive feed Stack Bag filter Auxiliary fuel (natural gas/oil) Fuel gas boiler Flue gas RDF fuel RDF gasifier Gas cooling and cleaning HP steam Steam turbine Bottom ash Additive feed Filter ash Fly ash Electricity, district heat

39 Stand Alone Gasification Plant for RDF Turbine Gas fired boiler Gas filtration Gas cooler Gasifier REF feeding

40 Electricity Production 160 MW fuel Gasification 120 bar, 540 ºC η e = 36 % 57 MW e CFB combustion 65 bar, 465 ºC η e = 33 % 53 MW e Grate firing 40 bar, 400 ºC η e = 25 % 40 MW e