Comprehensive treatment and recycling method for chlorobenzene waste liquor and waste residues

Abstract

The invention discloses a comprehensive treatment and recycling method for chlorobenzene waste liquor and waste residues. The method comprises the steps that the waste liquor generated in chlorobenzene production is added into waste residues containing iron ions, and the pH is controlled to range from 4 to 5; organic matter is recycled after being dried; the pH of an aqueous phase is adjusted to range from 9 to 10, the temperature ranges from 40 DEG C to 60 DEG C, suction filtration is conducted, and a first filtrate and first filter residues are obtained; the pH of the first filtrate is adjusted to range from 10 to 12, the temperature ranges from 40 DEG C to 60 DEG C, suction filtration is conducted, and a second filtrate and second filter residues are obtained; the second filtrate is partially returned back to a chlorobenzene production tail gas absorption system, the rest of the second filtrate is neutralized with collected acidic waste liquor, one part of the neutralized second filtrate returns back to a by-product hydrochloric acid synthesis system, the other part of the neutralized second filtrate serves as neutral waste liquor to be collected, and the first filter residues and the second filter residues are directly used in dispersed dyestuff wastewater treatment. The acidic waste liquor produced in chlorobenzene production is utilized for dissolving the waste residues, the products and the iron ions are recycled, wastewater recycling is achieved, zero release of wastewater and the waste residues is achieved, and the method meets the requirement of clean production.

Description

technical field [0001] The invention belongs to the technical field of three-waste treatment of chemical wastewater, waste residue, and in particular relates to a method for treating waste residue produced by chlorinated benzene with waste liquid produced by chlorinated benzene. Background technique [0002] Benzene monochloride is an important organic chemical intermediate, widely used in dyestuffs, pesticides, pharmaceuticals and other industries. At present, the domestic production of chlorinated benzene is prepared by reacting benzene and chlorine in a chlorination reactor under the catalysis of iron catalyst. The ferric chloride and acid produced by the reaction are washed with water and alkali, and then purified by rectification to obtain the finished product of benzene chloride. The process is mature, but the consumption of clean water and alkali is large, the amount of waste water is large, and iron sludge of ferric hydroxide is produced. At present, these waste li...

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Problems solved by technology

[0004] For example, the patent document CN 102584523 A discloses a crude chloride solution washing and alkali washing device and a water washing and alkali washing method in the production of chlorinated benzene. The crude chloride solution enters the crude chloride solution storage tank through water washing and alkali washing, and the acid produced Water is neutralized with lye. This patent document solves the problem of continuous use of clean water and continuous discharge of waste acid water. However, a large amount of waste water produced by washing is still neutralized with lye. Neutralization will inevitably produce iron hydroxide. This document does not This part of the content is reported. In addition, the wastewater generated by alkali washing enters the crude chloride storage tank, and how to deal with it in the next step is also not introduced.

[0005] Patent document CN 103819306 A discloses a process for removing ferric chloride from the chlorinated liquid produced by the production of chlorinated benzene. It utilizes resin adsorption and analysis to effectively reduce the content of ferric chloride in the chlorinated liquid. A large amount of waste water is produced in the washing stage, which directly enters the waste water treatment, and does not really reduce the amount of chlorinated benzene waste water and the utilization of ferric chloride

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