Method and system used for producing dichloroethane EDC from low purity chlorine gas

Abstract

The invention provides a method and a system used for producing dichloroethane EDC from low purity chlorine gas. The method comprises following steps: S1, chlorine gas drying, wherein a chlorine gas drying tower is adopted for drying of low purity chlorine gas; S2, chlorine gas purification, wherein the dried chlorine gas is subjected to liquefaction, gas liquid separation, liquid chlorine gasification, and pressurization for purification so as to obtain refined chlorine gas; and S3, chlorine gas reaction, wherein the refined chlorine gas and ethene are introduced into a chlorination reactor for reaction so as to obtain crude EDC, the crude EDC is delivered through an EDC high boiling tower to remove high boiling products so as to obtain refined EDC. According to the method, low purity chlorine gas is converted into dichloroethane EDC high in added value, chlorine gas utilization rate is increased, and using of sodium hydroxide is reduced. According to the method, low purity chlorine gas is subjected to drying and purifying so as to reduce corrosion of chlorine gas on equipment and pipelines in EDC production process, so that the quality of produced EDC is increased, production process safety and reliability are increased, and the application prospect is promising.

Description

technical field [0001] The invention belongs to the field of comprehensive utilization of chemical production resources, in particular to a system and method for producing EDC by utilizing low-purity chlorine gas. Background technique [0002] Chlorine gas is a strong oxidizing agent and is inexpensive, so it has a wide range of practical uses. However, chlorine gas is a poisonous gas, so the waste chlorine gas generated in the chemical production process usually needs to be recovered and reused. The low-purity chlorine gas in the traditional process is usually absorbed by sodium hydroxide to produce sodium hypochlorite, which not only wastes low-purity chlorine gas, but also consumes sodium hydroxide. In addition, low-purity waste chlorine gas, especially low-purity wet chlorine gas, may corrode equipment and pipelines during the next reuse process, affecting the safety of the production process. [0003] Therefore, it has become an important subject in this field to expl...

AI Technical Summary

Problems solved by technology

However, chlorine gas is a poisonous gas, so the waste chlorine gas produced in the chemical production process usually needs to be recycled and reused

The low-purity chlorine gas in the traditional process is usually absorbed by sodium hydroxide to produce sodium hypochlorite, which not only wastes low-purity chlorine gas, but also consumes sodium hydroxide

In addition, low-purity waste chlorine gas, especially low-purity wet chlorine gas, may corrode equipment and pipelines during the next reuse process, affecting the safety of the production process

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