Integration of Catalytic CO2 Oxidation and Oxyfuel Sour Compression

摘要

Sulfur dioxide (SO₂) may be removed from carbon dioxide feed gas by contacting the carbon dioxide at an elevated temperature and an elevated pressure with a catalyst for oxidizing SO₂, in the presence of oxygen (O₂) to convert SO₂ to sulfur trioxide (SO₃); contacting SO₃ in the resultant SO₃-enriched carbon dioxide gas with water to produce sulfuric acid and SO₂-depleted carbon dioxide gas; and separating the sulfuric acid from the SO₂-depleted carbon dioxide gas. If present, NO_x is also removed from the carbon dioxide feed gas as nitric acid to produce SO₂-depleted, NO_x-lean carbon dioxide gas. The method has particular application in the removal of SO₂ and NO_x from flue gas produced by oxyfuel combustion of a hydrocarbon fuel or carbonaceous fuel, within or downstream of the CO₂ compression train of a CO₂ recovery and purification system.