Abstract: An improved low sulfur and ash pumpable fuel composition is provided comprised of a mixture of carbon black in fuel oil dispersed in an aqueous continuous phase, said mixture comprising from about 50 to about 80 weight percent of said fuel composition and said carbon black being present in said fuel composition in an amount of at least about 20 percent by weight. A method for the production of the noted fuel composition is also provided.

Abstract: An improved fuel composition is provided comprised of a colloidal dispersion of a heat-treated dewatered sewage sludge and a biocide-containing hydrocarbon fuel oil. A method is also provided for the incineration of sewage sludge comprised of providing a fuel composition comprised of a colloidal dispersion of a heat-treated dewatered sewage sludge in a biocide-containing fuel oil, and incinerating the fuel composition.

Abstract: An improved pumpable fuel composition is provided comprising in major proportion a particulate solid fuel and in minor proportion sewage sludge, the improvement wherein said sewage sludge comprises from about 90 to 98 percent by weight of water and which sewage sludge has been subjected to heat treatment at a temperature in the range of from about 150.degree. to 500.degree. F. and subjected to pressures sufficient to both maintain the water content of the heat treated sewage sludge within the range of from about 90 to 98 percent by weight and to effect a lower viscosity for the sewage sludge upon return of the sewage sludge to ambient conditions. A method for the production of the improved fuel composition is also provided.

Abstract: Combustion gases from combustion of a coal-in-oil fuel mixture are used as an inert carrier gas in a fluid energy pulverizer used in the formation of the fuel mixture. A portion of the hot combustion gases is separated, cooled and compressed and passed to a heat exchanger where that portion is heated by the remainder of the combustion gases, the hot, pressurized portion led to the fluid energy pulverizer for use as a carrier gas for pulverizing of further coal.