Coal-water slurry combustion tests

This paper reports on the testing of slurries of different coals prepared by various vendors in order to establish typical ranges of physical and chemical properties and to determine the effect of these and rheological properties on atomization and combustion behavior. Six slurries provided by five vendors were tested to establish typical viscosity and solids levels of currently produced slurries. A key task of this project was the correlation of performance to the physical properties of a coal-water slurry (CWS). Topics considered include the 80 million Btu per hour burner test, atomizer/burner development, burner register development (cold flow modeling), a combustion performance comparison of CWS to parent coal, and combustion tests with an industrial boiler. Preliminary results indicate that slurry additives must be chosen carefully and with consideration of the slagging behavior of coal ash. It is demonstrated that, with the proper combination of burner and atomizer design, CWS can be successfully burned with carbon conversion efficiencies within 1 to 2% of that of the base coal fired under similar conditions. Includes 3 tables and 2 drawings.