WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Fluidized Bed Combustion of Biomass and Waste-derived Fuels –

Current Status and Challenges

Mikko HupaÅbo Akademi University

Turku, Finland

Waste-To-Energy Research and Technology Council, WTERT 2005 Fall Meeting at Columbia University

New York City, October 20-21, 2005

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Åbo Akademi University

Turku

FINLAND

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Åbo Akademi UniversityProcess Chemistry Centre

- Combustion chemistry- Wood and paper making chemistry- Sensors and process analysis- Kinetics and catalysis

20 faculty and post docs35 ongoing PhD ThesesIntense collaboration with industry

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Fluidized Bed Combustion of Biomass and Waste-derived Fuels –

Current Status and Challenges

• Introduction• Status of the FBC technology• Current research• Fluidized bed gasification• Conclusions

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Bubbling Fluidized Bed Combustion

Air

Air

Fuel

Fuel: Fresh, Partly Pyrolysed, Char

Bed material:Quartz, Limestone; fresh, calcined, sulphated

Void Space

Ash

Flue Gas + Fly Ash

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Circulating Fluidized Bed Combustion

Air

Air

Fuel

Fuel: Fresh, Partly Pyrolysed, Char

Limestone:Fresh, Calcined, Sulphated

Void Space

Ash

Flue Gas + Fly AshCyclone

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Fluidized Bed Combustion Systems

BFBC: Bubbling Fluidized Bed Boilers- fluidization velocity 1-3 m/s- reactive fuels (wood and biomasses)

CFBC: Circulating Fluidized Bed Boilers- fluidization velocity 6-10 m/s- less reactive fuels (coal, oil shale, petroleum coke)

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Fluidized bed boilers – common features

+ low combustion temperature+ flexible to fuel quality and variations+ high combustion efficiency+ low NO+ easy SO2 reduction

- ash components may cause bed sintering- residual ash may be difficult to dispose

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Commercial status

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Number of FB devices worldwide (2004)

0

200

400

600

800

1975 1980 1985 1990 1995 2000Year

Cum

ulat

ive

num

ber CFBC

BFBCPFBCFBG

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Capacity of FB devices worldwide (2004)

0

20 000

40 000

60 000

80 000

1975 1980 1985 1990 1995 2000by year

Cum

ul. c

apac

ity [M

Wth

]

CFBCBFBCPFBCFBG

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

LUVO

Superheatersand reheaters

Boilertubes

Fuelfeed Fu

rnac

eEconomizers

Steamdrum

Airfeed

Cyc

lone

Ashhoppers

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Alholmen CFBCJakobstad, Finland

550 MW (545 C)

Peat, Bark, REF, Forest Residue, Sawdust, Coal, Oil

Boiler Efficiency 92 %

NOx 50 mg/MJ SO2 100 mg/MJParticulate 30 mg/m3n

Kvaerner Power Oy - 2001

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Mälarenergi AB, Västerås

157 MWth

170 bar540 C

wood residuespeatcoal

Foster Wheeler2002

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Capacity of CFBCs worldwide (2005)

0

200

400

600

800

1000

1975 1980 1985 1990 1995 2000 2005 2010Year

Cap

acity

[MW

th]

Duisburg IGermany

Robert son Texas-New Mexico

Gardanne France

Poludniowy Koncern Energet yczny (PKE)Poland

Thermal Power (MWth) of the CFBCs Worldwide

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

• 150 MWth range: 50+ units operating

• 300 MWth range: 10 operating + 10 under construction

• 400 MWth+ range: 100 units commisioned/under constr.

Boilers in by Chinese Companies Zhongyang Luo, Kefa Zen (2005)

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Capacity of FB devices worldwide (2004)

0

20 000

40 000

60 000

80 000

1975 1980 1985 1990 1995 2000by year

Cum

ul. c

apac

ity [M

Wth

]

CFBCBFBCPFBCFBG

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Capacity of FB devices worldwide (2004)

0

40 000

80 000

120 000

160 000

1975 1980 1985 1990 1995 2000by year

Cum

ul. c

apac

ity [M

Wth

]

CFBCBFBCPFBCFBG

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Capacity of FB devices worldwide (2004)

0

40 000

80 000

120 000

160 000

1975 1980 1985 1990 1995 2000by year

Cum

ul. c

apac

ity [M

Wth

]

ChinaCFBCBFBCPFBCFBG

CFBC in China by Chinese companies

(estimate)

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Fuels

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Biofuels – Waste derived fuels –“Opportunity fuels” for FBC?

Forest residuesAnnual cropsPruningsShells, husks & hullsOlive stonesRDF (refuse derived fuels)Waste sludgesMBM (meat and bone meal)Chicken litterCoal SlurryPet coke

Åbo Akademi Fuel Data Bank

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Biofuels – Waste derived fuels –“Opportunity fuels” for FBC?

Forest residues EmissionsAnnual cropsPrunings Bed sinteringShells, husks & hullsOlive stones Fouling & corrosionRDF (refuse derived fuels)Waste sludgesMBM (meat and bone meal)Chicken litter Fuel Mixtures!Coal SlurryPet coke

Åbo Akademi Fuel Data Bank

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Emissions

100 %

100 ppm

1 %

1 ppm

1 ppb (µg/kg)

1 ng/kg

1 pg/kg -15

CO2 Carbon Dioxide

CO Carbon Monoxide / CxHy Hydrocarbons

PAH Polyaromatic Hydrocarbons

As, Cr, Ni, V, Pb, Cd, Hg,... Heavy Metals

Dioxins, Furans

SO2 Sulfur Dioxide / NOx Nitrgen Oxides-5

-10

0

Flue Gas Emission Components

100 %

100 ppm

1 %

1 ppm

1 ppb (µg/kg)

1 ng/kg

1 pg/kg -15

CO2 Carbon Dioxide

CO Carbon Monoxide / CxHy Hydrocarbons

PAH Polyaromatic Hydrocarbons

As, Cr, Ni, V, Pb, Cd, Hg,... Heavy Metals

Dioxins, Furans

SO2 Sulfur Dioxide / NOx Nitrgen Oxides-5

-10

0

Flue Gas Emission Components

Aerosol Aerosol ParticlesParticles

EU Directive on Incineration of Waste Containing Fuels

Acidic Gases• HCl 10 mg/m3n (on-line)• HF 1.0 mg/m3n (on-line)• SO2 50 mg/m3n (on-line)• NOx 200 mg/m3n (on-line)

Dust 10 mg/m3n (on-line)

Metals, ”EDD”• Hg 0.05 mg/m3n (twice a year)• Cd+Tl 0.05 mg/m3n (twice a year)• Sb+As+Co+Cr+

Cu+Pb+Mn+Ni+V 0.5 mg/m3n (twice a year)

(0.05 mg/m3n in flue gases ≈ 0,4 mg/kg dry fuel)

Dioxins and furans 0.1 ng/m3n (measurement twice a year)

Recovered Wood Fuel Metal Contents (ppmw = mg metal/kg fuel)

heavy metals

0.00

50.00

100.00

150.00

200.00

250.00

300.00

350.00

As Cd Co Cr Cu Hg Mn Ni Pb Sb Tl V Zn

mg/

kg fu

el

Rest fraction, analysedLeached in HClLeached in AcetateLeached in H2OUntreated Fuel

corrected value

As Cd Co Cr Cu Hg Mn Ni Pb Sb Tl V Zn

ppmw

300

200

100

0

Fouling and corrosion

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

BFBC for Biomass Fuels

Rice huskEucalyptus bark

Steam temperature for BFBCs worldwide (2005)

100

200

300

400

500

600

700

1975 1980 1985 1990 1995 2000 2005 2010Year

Tem

pera

ture

[°C

]

Ash Elements in Spruce Tissues(J. Werkelin 2005)

Five Spruce Tissues

Wood Bark Twigs Needles Shoots

Ash Elements in Spruce Tissues(J. Werkelin 2005)

Corrosion Test by Alkali Salts

Beforeheat treatment After heat treatment

Prepared for SEM

Corosion Analysis by SEM

450°C500°C

525°C550°C575°C600°C

Salt 0Salt 5

Salt 6Salt 7

Salt 8Salt 9

Salt 10

0

20

40

60

80

100

Cor

rosi

on l

ayer

thic

knes

s m

Steel: ATime: 168 h

Corrosion due to Alkali Salts

120

140

(Skrifvars et al. 2005)

Steel: BTime: 168 h

Corrosion due to Alkali Salts

450°C500°C525°C550°C575°C

600°C

01020304050607080

90100

Cor

rosi

on la

yer t

hikc

ness

m

Salt 5Salt 6

Salt 7Salt 8

Salt 9Salt 10

Salt 0

(Skrifvars et al. 2005)

450°C500°C 525°C550°C575°C 600°C

0102030405060708090

100

Cor

rosi

on la

yer t

hick

ness

μm

Steel: CTime: 168 h

Corrosion due to Alkali Salts

Salt 5Salt 6

Salt 7Salt 8

Salt 9Salt 10

Salt 0

(Skrifvars et al. 2005)

Gasification

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

CFB Gasifier

850 °C

900 °C

BOTTOM ASH COOLING SCREW

HOT LOW CALORIFICGAS (750 - 650 °C)

UNIFLOW CYCLONE

FUEL FEED

REACTOR

BOTTOM ASH

GASIFICATION AIR FAN

COOLING WATER

AIR PREHEATER

RET

UR

N L

EG

Foster Wheeler

BIOMASS GASIFICATION - COAL BOILER - LAHTI PROJECT

Bottomash

Gasifier

Coal

540 蚓 /170 bar

Processing

Biomass

Fly ash

Pulverized coal flames

Gas flame

Natural Gas

50 MW

300 GWh/a -15 % fuel input

1050 GWh/a -50 %

350 MW

650 GWh/a -35 %

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

CO2 Reduction -10 %

Foster Wheeler

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Conclusions (i)

• FBC rapidly expanding – now especially in China

• CFBC - upto 1000 MWth- novel cyclones and superheaters

• BFBC - interesting for reactive fuels

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Conclusions (ii)

• PFBC well demonstrated in 800 MWth class• FB gasifiers promising for producing gas to co-

firing

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Conclusions (iii)

• Waste derived fuels great potential for FBC• Challenge to boiler manufacturers & operators:

– Emission control (heavy metals)– Bed sintering and fouling control– Corrosion control– Multifuel firing and fuel interaction

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi

Aknowledgements

B. Leckner, L-E. Åmand (Chalmers), H. Tran (Toronto)

C. Mueller, R. Backman, B-J. Skrifvars, M. Zevenhoven, P. Yrjas, S. Kallio, P. Kilpinen, J. Konttinen, M. Theis, J. Werkelin (Åbo)

Kvaerner Power, Foster-Wheeler, Vattenfall, Metsä-Botnia, Andritz, International Paper

Tekes, Academy of Finland

WTERT 2005 Fall Meeting at Columbia University, October 20, 2005 Mikko Hupa, Åbo Akademi