Abstract: In order to decrease the SO₂ content in the regenerated flue gas of the heavy oil catalytic cracking unit (RFCC) and reduce the processing load of the subsequent flue gas desulfurization and dust removal device, SINOPEC Guangzhou Company adopted RFS09 sulfur transfer agent. The results of industrial tests showed that the SO₂ concentration of the flue gas was reduced significantly after the application of RFS09, the COD concentration of the sulfur-containing external drainage was decreased, and the SO₂ concentration of the purified flue gas was decreased from 3.56 g/m³ to 2.28 g/m³. The use of sulfur transfer additive did not adversely affect the yield of major products, such as gasoline and liquefied gas, and the quality of the equilibrium catalyst.

Key words: sulfur transfer agent, SO2, fluid catalytic cracking, flue gas desulfurization