The oxygen blown integrated gasification combined cycle starts out by gasifying (partially combusting) coal with pure O2 to produce CO and H2 (syngas). This syngas (itself a valuable chemical feedstock) is then cleaned up (removing sulphur and other contaminants), before steam is added and the water-gas shift reaction is effected:
H2O + CO = H2 + CO2
to produce more H2 and transform the CO to CO2. The H2 and CO2 mixture is then separated, perhaps by using a membrane which is permeable only to H2. The CO2 is sequestered and the H2 is burned in a gas turbine or used in a fuel cell.
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