Chemical looping removal of ventilation air methane

Abstract

Methane is removed from ventilation air by cycling metal or metal oxide particles in a chemical looping process in one or more reactors where the metal particles are alternately reduced and oxidized, and passing ventilation air through one or more of reactors to convert the air plus methane into reduced air, water and carbon dioxide. In one variation, a hydrogen generator and a regenerator are used to alternatively reduce and oxidize the particles such that ventilation air methane introduced into a combustor provided with hydrogen from the hydrogen generator can be processed in the regenerator to produce air, water and carbon dioxide. Other variations involve using three reactors in the chemical looping process, or an array of parallel inclined plates forming lamellas between upper and lower reactors to keep lighter particles in the upper oxidizer reactor and heavier particles in the lower reducer reactor.