Method for efficiently recycling salt-containing sewage by magnetic synergistic electrodialysis

Abstract

The invention discloses a method for efficiently recycling salt-containing sewage by magnetic synergistic electrodialysis; the salt-containing sewage is introduced into a magnetic synergistic electrodialysis device, ions in an acid chamber, an intermediate chamber and an alkali chamber are enriched towards inlets of all chambers under the action of an external magnetic field and an electric field, and the concentration of an ion solution at the inlets is increased; and as the water flow directions of the intermediate chamber, the acid chamber and the alkali chamber are different, a concentration difference is formed on the two sides of an ion exchange membrane, the ion exchange rate in electrodialysis is enhanced by utilizing a concentration gradient, the quality of a product at an outlet is improved, the accumulation of ions on the surface of the membrane is reduced, and finally, five products of high-quality and high-purity acid, alkali, hydrogen, oxygen and purified water are produced. The method is simple and easy to operate, the ion transmembrane transfer efficiency is improved, membrane damage is reduced, the problem that ions are accumulated due to the influence of the concentration gradient in the electrodialysis process is solved, the treatment effect of the salt-containing sewage is improved, the method can be applied to the industry on a large scale, and the process time of saline water recovery treatment is effectively shortened.

Description

technical field [0001] The invention belongs to the field of waste water purification, and in particular relates to a method for highly efficient recycling of saline waste water by magnetic cooperative electrodialysis. Background technique [0002] With the continuous development of human society, water bodies are gradually polluted, and more and more toxic and harmful salts enter the water. Human industrial development has caused great damage to water bodies, especially the salty sewage produced by industries such as mining, metallurgy, chemical industry, electroplating and electronics industries. At the same time, water pollution has brought great harm to human beings. In recent years, water pollution incidents have occurred frequently, and the amount of saline sewage is increasing year by year. It has the characteristics of strong toxicity, carcinogenicity, mutagenicity, refractory, easy enrichment, long-term persistence, etc., and can enter the human body through the fo...

AI Technical Summary

Problems solved by technology

For example, in the adsorption method, the adsorption capacity of the adsorbent is limited and the selectivity is high, so the application range of the adsorption method is limited to the treatment of low-concentration, single-component brine, and the adsorption method also has large investment, high operating cost, and sludge Problems such as large amount of production, difficult discharge of treated water, etc.

Because the electrochemical method does not need to add chemical reagents during the treatment process, it reduces the cost of wastewater treatment and does not cause secondary pollution. In particular, it can successfully realize the treatment and recovery of heavy metals in wastewater, and has a good application in the treatment of salty wastewater. Prospect; however, its drawback is that as the reaction proceeds, ions are continuously precipitated, resulting in a decrease in the concentration of ions in the original solution, causing an increase in resistivity and an increase in power consumption. Therefore, the application of electrolysis in the treatment of low-concentration saline sewage is limited to a certain extent.

Electrodialysis has the advantages of reliable technology, small footprint, and low operating costs. It is especially suitable for treating saline sewage with high ion concentration and low organic matter concentration. However, due to the large damage to the ion exchange membrane during the reaction process, in practical applications Difficult to run stably for a long time, usually used for primary desalination

[0004] Patent CN103073096A discloses a device for electromagnetic cooperative electrodialysis treatment of charged ions in wastewater. The main treatment object is heavy metal wastewater. During the treatment process, the magnetic field device accelerates the migration of anions and cations in the electrolytic cell to the electrode plate, and the heavy metal ions are gradually enriched in the electrode plate. At the same time, ions are easy to accumulate on the exchange membrane, which reduces the ion exchange rate of the ion exchange membrane and affects the ion separation effect, and the obtained product is still waste salt that has not been used by resources.

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