Process for treating waste water for production of trimethyl phosphite

Abstract

The invention discloses a method for processing wastewater in the production of trimethyl phosphite, belonging to the wastewater treatment in the chemical process technical field. The processing method comprises the following: firstly, a step of standing and delamination, which is to delaminate oily solvent and water in the wastewater; secondly, a step of heating and concentration, which is to heat the wastewater to between 100 and 140 DEG C and to make the proportion of concentrated solution reach between 10.5 and 1.20; thirdly, a step of cooling crystallization, which is to obtain crystal ammonium chloride and mother liquor; fourthly, a step of separation and drying, which is to separate out, dry and dehydrate ammonium chloride products and to recycle the mother liquor. The method adopts the preferable proposal that: standing and the delamination are performed by a two-stage wastewater disposal basin in turn; the wastewater is preheated by distillation waste heat during the producing procedure before heating and concentration; and evaporated water vapor during the concentration process is condensed and then recycled. The method has simple and feasible technique, low cost and good effect, has the content of the reclaimed ammonium chloride reach between 90 and 99.8 percent, realizes resource recycle, avoids environmental pollution, and generates good environmental benefit, economic benefit and social benefit.

Description

technical field [0001] The invention relates to a wastewater treatment method in the production of trimethyl phosphite, belonging to the technical field of wastewater treatment in chemical production. Background technique [0002] Trimethyl phosphite is an important intermediate in the production of medicines and pesticides. The enphosphonate pesticides and insecticides produced by it are widely used in agriculture and forestry in my country, with good insecticidal effect and great demand. At the same time, trimethyl phosphite is also used in the manufacture of plasticizers, flame retardants and stabilizers in the wood industry, and has a good prospect for development and application. The main production process of trimethyl phosphite is to use phosphorus trichloride and methanol as the main raw materials, use xylene as the solvent, and synthesize the reaction to generate trimethyl phosphite. Hydrogen chloride gas is generated in the process, and NN-dimethylaniline is used ...

AI Technical Summary

Problems solved by technology

Due to the high cost of treatment, the production cost is greatly increased, which is generally unbearable for enterprises. Most of the trimethyl phosphite production enterprises discharge the wastewater directly, causing great environmental pollution and waste of resources.

Therefore, wastewater treatment in the production process of trimethyl phosphite has always been a major bottleneck restricting the survival and development of enterprises.