Process for recovering and refining potassium chloride in organic chemical wastewater

Abstract

The invention discloses a process for recovering and refining potassium chloride in organic chemical wastewater. The process comprises the following specific steps: a potassium chloride aqueous solution enters a standing layering tank, a water layer and an oil layer are separated, the oil layer returns to a production system, the water layer enters a precision filter, effluent water obtained by filtration enters a resin adsorption tower, phenol, chlorobenzene and the like are adsorbed by adsorption resin, effluent water obtained from the resin adsorption tower enters a coagulation sedimentation tank, the pH of the potassium chloride aqueous solution is adjusted to be neutral, the separated supernatant overflows to a supernatant tank, effluent water obtained from the supernatant tank is filtered, the filtered water reaches a metal special resin tower to remove metals, effluent water obtained from the metal resin tower enters a middle water tank, effluent water obtained from the middle water tank is pumped into an MVR evaporation system by using a pump, and finally effluent water obtained from the MVR evaporation system enters a cooling crystallizing tank for cooling crystallization,and a salt obtained by the cooling crystallization is used as the product. Compared with the prior art, the process provided by the invention has the following advantages: organic pollutants and metal ions in the wastewater are efficiently removed by utilizing the resin, the high-quality potassium chloride is recovered, the waste is recycled, the regeneration treatment is convenient, the use period is long, the operation is stable, the operating costs are saved, and the automation degree is high.

Description

technical field [0001] The invention relates to the technical field of recovering potassium chloride from organic chemical wastewater, in particular to a process for recovering and refining potassium chloride from organic chemical wastewater. Background technique [0002] The wastewater in the production process of organic chemical wastewater contains high salt, high COD, and metal ions. The traditional sewage treatment process cannot efficiently remove organic matter and metal ions in the wastewater. The evaporated salt is treated as hazardous waste, which increases the cost of the enterprise. It also wastes resources. [0003] Disadvantages of the traditional process of treating potassium chloride in chemical wastewater: [0004] 1. The traditional process directly sends the wastewater to the MVR for evaporation, and the mixed salt is treated as solid waste, and the waste of potassium chloride is very high. [0005] 2. The traditional process of treating this kind of sol...

AI Technical Summary

Problems solved by technology

[0004] 1. The traditional process directly sends the wastewater to the MVR for evaporation, and the mixed salt is treated as solid waste, and the waste of potassium chloride is very high.

[0005] 2. The traditional process of treating this kind of solid waste requires a lot of equipment and chemicals, such as evaporation towers, heat exchangers, and some of them may also need expensive equipment such as reactors

Therefore, it is not cost-effective to produce mixed salt first and then distinguish potassium chloride.

[0006] 3. For some wastewater, other valuable substances except potassium chloride will cause waste

[0007] 4. The pure distillation separation process has relatively high energy consumption and a large steam consumption

[0008] 5. Membrane separation technology can indeed solve this problem, but high-tech must bring economic pressure

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