Biomass and sewage sludge are attracting increasing interest in power plant technology as a source of carbon-dioxide-neutral fuels. A new way to reduce the consumption of fossil fuels could be the co-combustion or co-gasification of coal and biomass or coal and sewage sludge. In both cases, pyrolysis is the first step in the technical process. In order to obtain detailed information about the pyrolysis of coal/biomass and coal/sewage sludge mixtures as well as unblended fuels, the “Institute fu¨r Verfahrenstechnik und Dampfkesselwesen (IVD)” at the University of Stuttgart has carried out investigations using an electrically heated entrained flow reactor. The test runs provided information about fuel conversion efficiency, pyrolysis gas and tar yield, and composition of pyrolysis gas and tar. Besides gas and tar analysis investigations regarding the path of trace elements, like heavy metals, alkali, chlorine and nitrogen components, during the pyrolysis process varying different parameters have been carried out. The fuel nitrogen distribution between pyrolysis gas, tar, and char has been analyzed, as well as the ash composition, and, thus, the release of mineral components during pyrolysis.

1.
Kicherer A., Gerhardt T., Spliethoff, H., and Hein, K. R. G., “Co-Combustion of Biomass/Sewage Sludge with Hard Coal in a Pulverized Fuel Semi-Industrial Test Rig,” Final Report, in: Bemtgen, J. M., Hein, K. R. G., and Minchener, A. J., “Combined Combustion of Biomass/Sewage Sludge and Coals, EC-Research Programme,” APAS-Contract COAL-CT92-0002, Institute for Process Engineering and Power Plant Technology, University of Stuttgart, 1995.
2.
Lungwitz H., “Thermische Kla¨rschlammbehandlung,” Berichte der Abwassertechnischen Vereinigung (ATV) Nr. 42, St. Augustin, 1992.
3.
Kaminsky W., “Kla¨rschlammpyrolyse: Vor dem großtechnischen Einsatz,” Chemische Industrie Nr. 6, 1987.
4.
Lindner K.-H., “Anforderung an die Kla¨rschlammentsorgung,” Berichte der Abwassertechnischen Vereinigung (ATV) Nr. 42, St. Augustin, 1992.
5.
Greul, U., Magel, C, Moersch, O., Ru¨diger, H., Storm, C., Schnell, U., Spliethoff, H., and Hein, K. R. G., “Einsatz von kohlesta¨mmigem Pyrolysegas als Reduktionsbrennstoff,” Final Report, Proj. No. 0326766A, German Federal Ministry of Education, Science, Research, and Technology BMBF, Bonn, 1996.
6.
Ru¨diger, H., Gerhardt, T., Spliethoff, H., and Hein, K. R. G., “Co-Combustion Concepts for Sewage Sludge in a Coal Fired Furnace Using Pulverized or Pre-Pyrolysed Feedstock,” Finnish-Swedish Flame Days, Naantali, Finland, 1996.
7.
Ru¨diger
H.
,
Kicherer
A.
,
Greul
U.
,
Spliethoff
H.
, and
Hein
K. R. G.
, “
Investigations in Combined Combustion of Biomass and Coal in Power Plant Technology
,”
Energy & Fuels
, Vol.
10
, No.
3
, pp.
789
796
,
1996
.
8.
Storm
C.
,
Spliethoff
H.
, and
Hein
K. R. G.
, “
Behaviour of Trace Elements During the Pyrolysis of Biomass and Sewage Sludge
,”
9th ICCS’97, Essen, Germany, DGKM Tagungsbericht 9703
, Vol.
II
, Pp.
721
724
,
1997
.
9.
Spliethoff, H., Ru¨diger, H., Greul, U., Spliethoff, H., and Hein, K. R. G., Kombinierte Minderung der NOx Bildung und Reduzierung von gebildetem NOx bei der Verbrennung von Steinkohle, Phase 3,” Final Report, Proj. No. 0326535C, German Federal Ministry of Research, and Technology BMFT, Bonn, 1993.
10.
Ruck B., “Influence of Tracer Particle Size on Flow Information in Laser Doppler Anemometry,” (in German), Technisches Messen-tm, No. 7/8, 1990.
11.
Smith, I. W., and Watts, A., “Heat Exchange Between a Particle an Its Surroundings: A Theoretical Study,” Investigation Report, CSIRO, 1968.
12.
Ru¨diger H., “Pyrolysegas von festen biogenen und fossilen Brennstoffen zur Erzeugung eines Zusatzbrennstoffes fu¨r Feuerungsanlagen,” Berichte aus der Energietechnik, Shaker Verlag, Aachen, 1997.
13.
Ru¨diger, H., Greul, U., Spliethoff, H., and Hein, K. R. G., “Co-Pyrolysis of Coal/Biomass and Coal/Sewage Sludge Mixtures in an Entrained Flow Reactor,” Final Report, in: Bemtgen, J. M., Hein, K. R. G., and Minchener, A. J., “Co-Gasification of Coal/Biomass and Coal/Waste Mixtures,” EC-Research Programme, APAS-Contract COAL-CT92-0001, Institute for Process Engineering and Power Plant Technology, University of Stuttgart, 1995.
14.
Evans, R. J., Milne, T. A., “Molecular Characterization of the Pyrolysis of Biomass, 1: Fundamentals,” Energy & Fuels, Vol. 1, No. 2, 1987.
15.
Antal, M. J., “Biomass Pyrolysis: A Review of the Literature, Part 1 and 2,” Advances in Solar Energie, American Solar Energy Society, New York, 1983.
16.
Canel, M., and Wanzl W., “Pyrolysis of a Turkish Lignite at High Heating Rates,” Fuel, Vol. 73, No. 1, 1994.
17.
Sahm, H., Kla¨rschlamm als chemischer und biologischer Rohstoff, GVC-Tagung, 1984.
18.
Wandrasz, J., “Ausgewa¨hlte Probleme der Schlammverbrennung,” in Recycling von Kla¨rschlamm I, EF-Verlag, Berlin, 1987.
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