Filtration of soot/ash water slurries and improved partial oxidation process for hydrocarbon feedstocks

Abstract

An improved partial oxidation, gasification process using low grade hydrocarbon feedstock involving the steps of gasification, waste heat recovery and carbon removal under formation of a soot water slurry containing the unburned carbon and ash. The soot water slurry is filtered to form a filtercake of carbon and ash, which cake is removed from the process. A direct once-through, partial oxidation process is thereby established, avoiding the recycle of unburned carbon and ash. The method also comprises filtration of the soot-ash slurries containing 0.5-3% unburned carbon and 0.1-2% ash having appreciable amounts of Fe, Ni and V. The slurry is cooled to a temperature below 80.degree. C. and filtered while confined between movable closed belts maintaining a constant pressure against the shrinking mass of carbon/ash particles until the moisture content is reduced to below 80% by weight. Flocculating agents are added to the soot slurry before filtration, one in the form of a cationic and the other in the form of an anionic flocculation agent. A flaky, or granular filtercake suitable for further processing is obtained.

Dependencies are inferred from the claim text.