Ammonium Chloride Rare Earth Wastewater Treatment and Recycling Process

Abstract

The invention relates to a process for treating and recycling ammonium chloride rare earth wastewater. The ammonium chloride wastewater is completely recycled by diethyl phthalate (DEP), so that the ammonium chloride wastewater discharged in a rare earth smelting process can be completely recycled; dielectrophoresis is used for reinforcing the treatment efficiency of a membrane in DEP microfiltration and DEP nanofiltration, and compared with the conventional process in which high energy consumption is caused because clear water is needed to be introduced under high pressure for frequent backwashing and membrane filtration is forced to be stopped, the process has the advantages that: the work continuity and high efficiency of the membrane are achieved and energy consumption is low in the DEP microfiltration and the DEP nanofiltration; a nanofiltration membrane is adopted, so that ammonium ions and chlorine ions in ammonium chloride are selectively separated from the wastewater and enriched; compared with a process for treating industrial wastewater through a reverse osmosis membrane and electrodialysis, the process has the advantage that: osmotic pressure required by the nanofiltration membrane is low, so that the energy requirement and treating cost are reduced; chlorine, hydrogen and ammonia water are generated by electrolyzing high-concentration ammonium chloride solution, and the hydrogen and the chlorine are introduced into a hydrogen chlorine fuel cell to release electric energy so as to partially compensate electricity consumption in the whole separation and recoveryprocess; meanwhile, dilute hydrochloric acid is generated after reaction in the fuel cell is finished, and is recycled together with the ammonia water generated in the electrolysis process.

Description

technical field [0001] The invention belongs to the technical field of environmental protection, and relates to waste water treatment and recycling of effective substances mainly based on ammonium chloride in rare earth smelters, in particular to a process for the treatment and recycling of ammonium chloride rare earth waste water. Background technique [0002] Ammonia nitrogen is an important pollutant that pollutes water bodies. Excessive ammonia nitrogen content in water bodies not only destroys the ecological environment, but also causes great harm to the survival and health of humans, animals and plants. The ammonium chloride wastewater discharged from the rare earth smelter contains high concentrations of ammonium chloride, which is thousands of times higher than the discharge standard requirements. Although a variety of methods can be used to treat it, the currently commonly used biological oxidation method cannot treat ammonium chloride wastewater with a concentratio...

AI Technical Summary

Problems solved by technology

However, the proposed process flow and patented invention do not fully consider the complexity of the substances contained in ammonia nitrogen wastewater

For example, ammonium chloride wastewater discharged after rare earth smelting often contains water / oil emulsions and other suspended matter, and these substances will not only shorten the water treatment efficiency of the reverse osmosis membrane but also reduce the service life of the osmosis membrane

In addition, due to the high membrane pressure required in the reverse osmosis membrane process, this also means that it requires high water pumps in the process and consumes more energy. Electrodialysis technology also requires high energy. Moreover, the treated Ammonium chloride concentrate still contains other elements, which is not conducive to waste recycling

[0004] Through searching, no published patent documents identical to this patent application have been found

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