Method for purifying and removing thiosulfate from amine solution

Abstract

The invention provides a method for purifying and removing thiosulfate from an amine solution. The method for purifying and removing the thiosulfate from the amine solution comprises the steps that anORP measuring instrument is adopted, an ORP composite electrode is inserted into the amine solution, and hydrogen peroxide is added to the amine solution while an ORP value of the amine solution is detected to control the ORP value of an end point of an oxidation reaction to be 100-400 mV; when the ORP value reaches a specified value, adding of the hydrogen peroxide is stopped immediately while the temperature of the oxidation reaction process is controlled to be 10-70 DEG C; and a pH measuring instrument is adopted, an pH composite electrode is inserted into the amine solution, and a pH value of the oxidation reaction process is controlled to be 4-9. The method for purifying and removing the thiosulfate from the amine solution is simple in operation process, low in process cost and highin practicability.

Description

technical field [0001] The invention relates to the technical field of nonferrous metal smelting flue gas treatment, in particular to a method for removing thiosulfate radicals from an aqueous organic amine solution used in flue gas desulfurization. Background technique [0002] Coal combustion, metal smelting, acid production and other processes will have SO 2 If it is not absorbed and removed, it will be directly discharged into the atmosphere, which will form acid rain and pollute the environment. Since the 1950s, more than 200 flue gas desulfurization (FlueGas Desulfurization) technologies have been studied in the world, of which more than 20 have been applied in industry, and some are still in use today. There are many classifications of flue gas desulfurization technology methods. According to the state of use of desulfurizers, they can be divided into three types: wet desulfurization, dry desulfurization, and semi-dry desulfurization. Among them, wet desulfurization ...

AI Technical Summary

Problems solved by technology

This method is applied to the purification of tin smelting flue gas desulfurization amine liquid to remove thiosulfate ions, and some thiosulfate ions can be removed. However, the production practice results show that the tin smelting flue gas desulfurization adopts the Cansolv organic amine method, and the amine liquid Recycling, if the removal speed of the amine liquid purification unit (APU) equipped in the system is lower than the generation speed, the concentration of impurities in the amine liquid will increase, and if it exceeds a certain value, it will affect the normal operation of the desulfurization system and make the flue gas The desulfurization effect becomes worse

The practical results of some flue gas desulfurization industrial production enterprises in tin smelters show that the amine liquid is recycled for 20 months, the concentration of thiosulfate in the amine liquid rises rapidly, sulfur is precipitated, the pipeline and equipment are blocked, and the flue gas desulfurization system is damaged. Paralysis, loss of function, had to stop production

[0004] The amine solution thiosulfate removal method configured by the organic amine method of Canadian Cansolv Company has the following disadvantages: ① the removal rate of thiosulfate is low, only 20% to 30%; ② the resin exchange capacity is small, 1 One ton of resin can only exchange and remove about 1.7 kg of thiosulfate; ③ produce waste water

This method is effective, but the process is complicated, the operation is cumbersome, and the cost is high