Cofiring of wood and straw with coal in Germant- CARMEN ev

Co-firing of wood and straw with coal in Germany

C.A.R.M.E.N. Dr. R. BrĂśkeland

1 General Information 1.1 Primary energy consumption 1.2 Present CO2 reduction 1.3 Reasons for co-firing 2 CHP WĂźrzburg 2.1 Driving plan 2.2 Fuel handling 2.3 Results and experiences

Primary Energy Consumption in Germany 1998 14,320 PJ

C.A.R.M.E.N. Dr. R. Brรถkeland

nuclear power 12.3%

other 1.4%

brown coal 10.5%

mineral coal 14.2%

mineral oil 40.0%

water/wind 0.5%

natural gas 21.0% BMWi 1999

Energy-caused CO2 Emissions in Germany

C.A.R.M.E.N. Dr. R. Brรถkeland

1050 1000 cleared up of temperature

million t

950

real development

900 850 800 750 1990

1991

1992

1993

1994

1995

1996

1997

1998 BMWi 1999

Reasons for co-firing in Germany C.A.R.M.E.N. Dr. R. Brökeland

• Existance of large potential of forest residues and other biofuels • Immediatly use of biofuels possible • No or low investment costs, existing plant unitis for power generation • Co-firing tests to identify problems in fuel handling and influences on different plant units and emissions

Fuel handling in CHP WĂźrzburg C.A.R.M.E.N. Dr. R. BrĂśkeland

coal

scraper for emergency feeding1

boiler bunker

dump car (frog)

6

5

4

3

2

1

wood

coal storage place

balance belt conveyor 2

balance belt conveyor 1 coal funnel

underground bunker

boiler 3 bucket elevator

boiler 2

Results and experiences in CHP Würzburg C.A.R.M.E.N. Dr. R. Brökeland

• No problems at receiving of wood fuels • Some problems at the dosage causes by too large wood chips • No additional costs for modifications of the plant or feeding systems • No changes in emissions for dust, CO, NOx, PCDF/PCDD, PCB, chlorine benzene, phenol • Emissions of sulphur decreased by 13.6%, reduced requirement of hydrated lime • No continous measuring of total carbon necessary