STUDY OF UTILITY BOILERS FOR A COAL-WATER-SLURRY DEMONSTRATION TEST.

Commercialization of coal-water slurry (CWS) is within reach, but utilities still require evidence that they can fire CWS in full-scale boilers over the long term. This study lays the groundwork for a one-year CWS demonstration, outlining a test program and calculating retrofit and operating costs for seven typical oil-fired boilers. The 43-week test program includes characterization tests, long-term operating tests, and structured performance analyses to evaluate boiler operation under controlled conditions. Predicted boiler capacity for CWS firing ranges from 43 to 100% of manufacturers' ratings for the 7 candidate boilers. Potential erosion of convection tubes appears to be the primary factor limiting CWS firing. Researchers' derating predictions are conservative, assuming only minimum boiler modifications. Program estimates suggest that the program cost for a 400-MW unit would range from 13 million to 31 million, depending on the equipment required for ash handling and particulate control.