Aqueous slurry of a solid fuel and a process for the production thereof

An aqueous slurry of a solid fuel and a process and a means for producing said slurry are described. The aqueous slurry comprises a highly concentrated slurry of a pulverized, carbonaceous material having a particle size of at most 0.5 mm, and 0.02-2% by weight of at least two surface active additives. The solids content of the slurry is 65-90% by weight, preferably 70-80% by weight. The slurry is characterized in that the surface active additives include, as a major part, a water-soluble nonionic surface active agent which is an alkylene oxide adduct with a hydrophobic part and a hydrophilic part, said hydrophilic part consisting of at least one polyalkylene oxide chain with a length of at least 40, preferably 50-150 ethylene oxide units; and, as a minor part, an ionic surface active agent. The ionic surface active agent preferably has the general formula: (IX) wherein R1 and R2 are hydrogen or an alkyl group with 1-22 carbon atoms, provided that the sum of the number of carbon atoms of R1 and R2 is at least 6, and Z1 designates the group -SO3H, -CH2+NHR3R4X- or -CH2+NR3R4R5X-, wherein R3, R4 and R5 are alkyl and/or hydroxyalkyl groups with 1-4 carbon atoms and X is an anion, and n is 40-200.