Method for recovering high-purity organic salt from phosphorous-containing industrial wastewater

Abstract

The invention discloses a method for recovering a high-purity organic salt from phosphorous-containing industrial wastewater. The method comprises the following steps: evaporating and concentrating the phosphorous-containing high-salt industrial wastewater to obtain an organic salt rough product; washing the inorganic salt rough product by using a washing solution; removing phosphorous from the inorganic salt rough product; keeping the washed inorganic salt rough product in contact with oxygen-containing gas at the temperature of less than or equal to 1,000 DEG C; and carbonizing to obtain the high-purity inorganic salt, wherein the washing solution is salt water or industrial wastewater with high inorganic salt content. The method realizes resource recycling of industrial salt, phosphorous in the salt is removed by the high-salt wastewater, the treatment of wastes with wastes is realized, and the economic benefit is prominent; the method has the advantages of short process flow, no wastewater discharge, incapability of producing secondary pollution which is difficult to treat, recyclability of tail gas, obvious environmental protection effect and suitability for industrial application; meanwhile, the method is widely applied; and the purification of the industrial salt can be realized by using the method for all the pesticides and even high-salt wastewater in other industries.

Description

technical field [0001] The invention relates to a treatment method for salt-containing industrial wastewater, in particular to a method for recovering high-purity inorganic salt from phosphorus-containing salt-containing industrial wastewater. technical background [0002] In the production process of many organic or inorganic chemical products, a large amount of saline wastewater is often produced due to the process requirements, in which the sodium chloride content is higher than 1%, many are more than 10%, and some even reach more than 20%, which is high. The current mature treatment process for salty wastewater and high-salt wastewater is mostly evaporation, which will produce a large amount of by-product waste salt (NaCl). The sodium chloride content of this salt is more than 90%, and it contains a large amount of organic or inorganic impurities. It cannot be directly used as industrial raw material salt, let alone for food or medical use. Most manufacturers pile it up....

AI Technical Summary

Problems solved by technology

The sodium chloride content of this salt is more than 90%, and it also contains a large amount of organic or inorganic impurities. It cannot be directly used as industrial raw material salt, let alone for food or medical use. Most manufacturers pile it up.

The long-term storage of this salt not only occupies a large amount of land, but also poses a huge threat to the environment. The salt and impurities are easily lost, salinizing the surrounding soil, endangering the surrounding vegetation, and polluting the surrounding rivers, water sources, rice fields, etc.

[0003] The production process of glyphosate and triazine herbicides also produces a large amount of high-salt wastewater. At present, the commonly used treatment method is to obtain solid salt through evaporation and concentration. The solid salt content is about 90%, and the purity still cannot meet the requirements. be used effectively

Especially the glyphosate production wastewater contains a lot of phosphorus. Due to the nature of the wastewater, the concentrated solid salt is doped with phosphorus, which is very difficult to remove, which further increases the difficulty of solid salt purification.