Abstract: A coal aqueous slurry having a lower viscosity and resistance to thickening with time is provided. The coal aqueous slurry includes water, particulate coal comprising carbonaceous material and water-soluble minerals, a surfactant present in the coal aqueous slurry in an amount sufficient to disperse the particulate coal in the water and a chelating agent. The included chelating agent is capable of forming a chelation complex with the metal ions formed by the water-soluble minerals dissolving into the water. The presence of the chelating, or complexing, agent reduces coagulation of the coal particles, because the chelating agent complexes soluble mineral matter and thereby prevents collapse of the protective water layer surrounding the coal particles.

Abstract: A dispersion of coal in water includes particulate coal dispersed in an aqueous solution including a multi-component additive. The multi-component additive includes a water-soluble, nonionic wetting agent, a water-soluble, low molecular weight polymer, and a water-soluble, medium-to-high molecular weight polymer. The particulte coal has a particle size distribution with a major portion of particulate coal having a weight average particle size of from about 75 .mu.m to about 35 .mu.m and a minor portion of particulate coal having an average particle size of about 6 .mu.m to about 15 .mu.m.

Abstract: Coal-aqueous slurries having improved shear stability and lower viscosity are described. The use of a plurality surfactants each having hydrophilic portion with each surfactant hydrophilic portion having a different molecular weight are utilized in sufficient amounts to wet and disperse particulate coal and water. When two surfactants are utilized, coal-aqueous mixtures may be formulated having up to or over 70% by weight coal when the first surfactant has a hydrophilic portion comprising a relatively large number of ethylene oxide units and the second surfactant has hydrophilic portion comprising a relatively small number of ethylene oxide units.