The micronized slurry fuel was prepared by grinding the clean float coal with water in two stages. The first stage was a conventional 4-ft diameter overflow mill charged with a graduated load of 2-inch and smaller steel balls. The grinding was at about 44% solids with sufficient Diamond Shamrock A-23 dispersant added to provide fluidity. The ground slurry was screened and the small amount of plus 20-mesh (0.85-mm) material collected was discarded. The finish grinding was in a Draiswerke Perlmill Model PM-40 stirred ball mill charged with 3-mm chromium-steel media. The tumbling ball mill and the stirred ball mill were both operated in open-circuit with no classification or recycle. The finish-ground slurry was combined in a large blending tank to which additional water and dispersants were added as needed to achieve the target loading, viscosity and stability. A combination of anionic and nonionic dispersants were used in the final blend but no stabilizer was included in the formulation. Finished slurry properties are given in Table 1. Figure 2 is a rheogram of the flow properties of the slurry as determined with a Fann viscometer. The micronized powder fuel was also prepared from the clean float coal. The excess water was allowed to drain away and then the coal was pulverized in a Pulvocron PC-20 air-swept hammer mill and classifier systems at Bepex Corporation facilities in Minneapolis. The coal had dried during handling so the transport air did not have to be preheated for the pulverizer system to operate properly.