Preparation of a mixture of gases

摘要

A process for making a combustible gas consisting of hydrogen, carbon monoxide and methane comprises reacting iron or iron oxides with steam at high pressure (500 to 3000 p.s.i.g.) and temperature (1200 DEG to 2000 DEG F.) at 46 to produce hydrogen and reacting the hydrogen at the same pressure with solid carbonaceous material (e.g. coal, lignite, char) or atomized oil at 16 to make the combustible gas. The exothermic hydrogenation reaction at 16 may be neutralized thermally by an endothermic water gas reaction there by controlling the excess steam delivered to 16 via 48, 52, and hydrogen may be separated at 64 from the purified gas and recycled to 16 via 68, the hydrogen/steam in 52 being in that case delivered to 16 via 53. The solid fuel is delivered at 54 and is passed via 18 to a producer 10 supplied with preheated air and steam at 12, 14 respectively, the producer gas being used to reduce to iron at 26 the iron oxides circulated (by a gas, e.g. steam) from oxidizer 46 via 50. The high pressure is maintained (by valves &c.) in the reactors 10, 16, 26, 46, air entering the system at 40 being compressed at 38 by the energy of the spent producer gas leaving at 36. The product gas may be subjected to catalytic methanation at 72. A specific example is described, giving the compositions of the producer gas, hydrogen/steam gas in 52, and the final gas before and after methanation.