97/01806 Preparation of coal-water slurry fuels from impounded bituminous coal fines

Abstract

Over the last decade, there has been considerable interest in the utilization of coal refuse as a fuel for power generation. Much of the interest has been on using coarse coal refuse in fluidized-bed combustors, particularly those operated by independent power producers. Utilization of impounded coal fines has been limited because of the problems associated with handling wet fine coal. The amount of coal fines within active and abandoned slurry impoundments has been estimated to exceed two billion tons with an additional 40 to 50 million tons of coal fines being added to this inventory annually. Advanced fine coal cleaning techniques typically produce a wet fine coal product that has to be dewatered. The existence of large fine coal impoundments coupled with fine coal cleaning circuits which produce wet coal fines has lead some utilities to consider using coal-water slurry fuels (CWSF) to lower their fuel cost. One such utility is the Pennsylvania Electric Company (Penelec). Utility scale, demonstration testing at Penelec`s Seward Station of cofiring a low solids, low viscosity CWSF with pulverized coal has been summarized by Battista et al. 1995. More recent Seward test data on cofiring pulverized coal with CWSF prepared from cleaned impounded coal finesmore » is reported in Falcone Miller et al. 1996. This paper summarizes the findings of a recent study which focused on the preparation and utilization of low solids, low viscosity CWSFs prepared from cleaned coal fines recovered from fine coal slurry impoundments located in western Pennsylvania.« less