Method for jointly removing hydrogen sulfide and sulfur dioxide in mixed gas and recovering sulfur

The invention discloses a method for jointly removing hydrogen sulfide and sulfur dioxide in mixed gas and recovering sulfur. The method comprises the following steps: firstly, removing SO2 and part of H2S in a mixed gas by adopting a liquid-phase Claus reaction unit (1), then removing the residual H2S by using a complex iron absorption unit (2), enabling a desulfurization pregnant solution generated by the liquid-phase Claus reaction to enter a complex iron pregnant solution tank (4), further reacting with a complex iron desulfurization pregnant solution, enabling the desulfurization pregnant solution and the complex iron desulfurization pregnant solution to enter a complex iron regeneration unit (3), and regenerating the complex iron. The regenerated desulfurization barren liquor returns to the complex iron absorption unit (1), and sulfur in the desulfurization barren liquor is recovered in the sulfur recovery unit (5) after settling or floating. The method adopted by the invention is simple in process, SO2