Abstract:The collected fugitive gas desulfurization of a smelter adopts the sodium alkali process, and the acid tail gas desulfurization adopts the active coke process. The desulfurization device has the problem that the tail gas after desulfurization cannot meet the special emission limit requirements. This paper put forward the optimization scheme on the basis of discussing the operation status of the existing device (SO2≤100mg/m3, NO x ≤100mg/m3, particle content≤10mg/m3). The principle, process flow, equipment selection and system performance of ionic liquid desulfurization were mainly discussed. In view of the problems of large fluctuation of SO2 concentration in flue gas, unstable SO2 concentration in tail gas emission, excessive consumption of ionic liquid and high concentration of thiosulfate in ionic liquid, the corresponding treatment measures were put forward. After optimization, the SO2 concentration in the tail flue gas was less than 100mg/m3, and most of the time is less than 30mg/m3. Practice has proved that the desulfurization process is selected correctly, the design parameters are set reasonably, the device runs smoothly, and the desulfurization achieves the ideal effect.