Patent ID: 6692711
Filing Date: 2004-02-17
Classification: B01D,C10L

Abstract:
A process for producing a synthesis gas comprising a mixture of H2 and CO from a sour natural gas comprising mostly methane which also contains C4+/C5+ hydrocarbons, CO2, H2S, C2+ mercaptans and COS, with recovery of said C4+/C5+ hydrocarbons from said gas, which comprises(a) contacting said sour natural gas with an aqueous amine solution to remove most of said H2S and organic sulfur compounds to produce a sulfur reduced gas containing less than 2 vppm of total sulfur compounds; (b) cooling said sulfur reduced gas to a temperature sufficient to condense said C4+/C5+ hydrocarbons and some of the remaining sulfur compounds to liquids; (c) separating said condensed liquids from said cool sulfur reduced gas; (d) recovering said C4+/C5+ hydrocarbons; (e) heating said cool sulfur reduced gas to a temperature of at least about 100Â° F. to produce a heated sulfur reduced gas; (f) contacting said heated sulfur reduced gas with ZnO and then with nickel to remove more sulfur compounds from said heated sulfur reduced gas and produce a very low sulfur content gas comprising methane which contains less than 0.1 vppm of sulfur compounds; (g) passing said very low sulfur content gas produced in (f) into a synthesis gas generating zone in which it reacts with oxygen to form said synthesis gas.