Patent ID: 8308983

Claim:
A process to prepare a gas mixture of hydrogen and carbon monoxide from an ash containing carbonaceous feedstock comprising the following steps, (a) partial oxidation of the ash containing carbonaceous feedstock with an oxygen containing gas thereby obtaining liquid ash and a gas mixture comprising hydrogen, carbon monoxide and solids, (b) separating more than 90 wt % of the liquid ash from the gas mixture, wherein step (a) and (b) are performed in a reactor vessel provided with horizontally firing burner nozzles, which nozzles discharge a gas mixture comprising hydrogen, carbon monoxide and solids into a gasification chamber as present in the reactor vessel, and wherein liquid ash is present on an interior wall of the gasification chamber, wherein the gas mixture is discharged through an opening at the upper end of the gasification chamber and the liquid ash is discharged via an opening at the lower end of the gasification chamber, (c) reducing the temperature of the gas mixture, in the absence of the separated ash, from a temperature above 1000° C. to a temperature below 900° C. by contacting the gas mixture with a gaseous and/or liquid quench medium, (d) passing the gas mixture obtained in step (c) through a vertically positioned diptube wherein water is added to the gas mixture flowing through the diptube to obtain a gas/water mixture, (e) separating the liquid water from the gas/water mixture by passing the gas/water mixture through a water bath as present at the lower end of the diptube wherein the gas is discharged to a space above the water bath and effluent water is discharged from the water bath via a discharge conduit fluidly connected to said water bath, (f) passing the gas obtained in step (e) together with an amount of liquid water through a venturi mixer, and (g) passing the gas obtained in step (f) upwardly through a scrubber in which the gas contacts a stream of downwardly moving liquid water thereby obtaining a scrubbed gas mixture of hydrogen and carbon monoxide and used water, wherein part of the used water is used in step (d) as the water added to the gas mixture.