METHOD FOR REMOVAL OF SULFUR-CONTAINING COMPOUND FROM NATURAL GAS

摘要

All sulfur compounds can be efficiently removed from natural gas that contains hydrogen sulfide and other sulfur compounds such as mercaptan without using physical absorption. The process comprises an absorption step of treating natural gas by means of a chemical absorption method using an amine-containing solution to mainly remove hydrogen sulfide and carbon dioxide, an adsorption step of flowing the natural gas from the absorption step through a packed bed of a molecular sieve to mainly remove mercaptan, a recovery step of recovering sulfur compounds by converting the hydrogen sulfide removed in the absorption step into sulfur by means of the Claus process, a regeneration step of desorbing the mercaptan adsorbed on the molecular sieve in the adsorption step using heated gas and a reaction step of converting the mercaptan in the regeneration exhaust gas exhausted from the regeneration step into hydrogen sulfide. The reaction step is conducted by injecting steam or water at a ratio of H 2 O/S = 1 to 5 (molar ratio) relative to the sulfur in the regeneration exhaust gas in the presence of a catalyst under the conditions of a temperature level of 250 to 400°C and a pressure level of 1 to 10 MPa.