Device and method for removing chloride ions in ammonia desulfurization slurry by MVR evaporative crystallization

Abstract

The invention provides a device and a method for removing chloride ions in ammonia desulphurization slurry by MVR evaporative crystallization. An ammonium sulfate solution in a desulfurization tower is conveyed to an MVR evaporative crystallization system through a pump, the solution is pumped into a heater for heating under the action of an evaporation circulating pump and then enters an evaporation separation chamber for flash evaporation, and steam obtained through flash evaporation enters a heater shell pass to serve as heating steam and condensate water to be discharged after the pressureand the temperature are increased through secondary compression of a steam compressor. The ammonium sulfate solution is continuously concentrated to be crystallized in the evaporation process, afterthe solid content of the solution reaches 10-20%, the solution is pumped into a centrifugal separation system to be separated, dehydrated and discharged, chloride ions in the solution are crystallizedand discharged in the form of ammonium chloride to be removed, and centrifugally separated mother liquor returns to a mother liquor tank and then is pumped back to the evaporation separation chamberthrough a mother liquor pump to be recycled. By adopting the process, the chloride ions and the fluoride ions of the ammonia desulphurization system can be effectively removed, the operation energy consumption is low, and the reliability is good.

Description

Technical field[0001]The invention relates to an MVR evaporation crystallization device and method for removing chloride ions in ammonia desulfurization slurry, and relates to the technical field of environmental protection equipment.Background technique[0002]Ammonia desulfurization is an advanced desulfurization technology with high desulfurization efficiency, high recyclability, and no emissions of three wastes. It has a wide range of applications in all walks of life across the country. Because boiler coal or process water is rich in chloride or fluoride ions, ammonia desulfurization is a closed-loop system, resulting in a high content of chloride ions in the solution in the ammonia desulfurization system. When the chloride ion content exceeds 40,000 ppm, it will affect the desulfurization system. Circulating pumps, centrifuges and other moving equipment produced serious corrosion, which greatly affects the long-term stable operation of the ammonia desulfurization system and incr...

AI Technical Summary

Problems solved by technology

Because boiler coal or process water is rich in chloride ions or fluoride ions, ammonia desulfurization is a closed cycle system, resulting in a high content of chloride ions in the ammonia desulfurization system. When the chloride ion content exceeds 40,000ppm, it will affect the desulfurization system. Severe corrosion of circulating pumps, centrifuges and other dynamic equipment will greatly affect the long-term stable operation of the ammonia desulfurization system and increase the owner's operating costs

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