Molten metal hydrocarbon gasification process

Abstract

A process in which a high-purity, high-pressure hydrogen-rich gas stream and a high-purity, high-pressure carbon monoxide-rich gas stream are simultaneously produced separately and continuously using a molten metal gasifier that contains at least two zones, thereby avoiding the need to separate or compress the gases in down-stream equipment. In one version of the process, the steps comprise (a) introducing a hydrocarbon feed into a molten metal bath beneath the molten metal surface in a feed zone operating at a pressure above 5 atmospheres absolute, and decomposing the hydrocarbon feed into hydrogen, which leaves the feed zone as a hydrogen-rich gas, and into carbon, which dissolves in the molten metal and increases the carbon concentration, but controlling the carbon concentration to at or below the limit of solubility of carbon in the molten metal, (b) transferring a portion of the molten metal from the feed zone to another molten metal oxidation zone operating at a pressure above 5 atmospheres absolute into which an oxygen-containing material is introduced beneath the molten metal surface to react with a portion of the carbon to form a carbon monoxide-rich gas which leaves the oxidation zone, wherein the carbon concentration in the molten metal is controlled so that it does not reach the concentration at which the equilibrium oxygen concentration would exceed its solubility limit in the molten metal and a separate iron oxide phase would accumulate, (c) transferring at least a portion of the molten metal which has a lower carbon concentration from the oxidation zone back to the feed zone, and (d) passing said separate high-pressure, high-purity hydrogen-rich and carbon monoxide-rich gas streams out of their respective zones, removing entrained dust and cooling the gas streams to temperatures suitable for use in industrial processes.