Recovery treatment process of mercury-containing waste hydrochloric acid

Abstract

The invention relates to a recovery treatment process of mercury-containing waste hydrochloric acid, belonging to the chemical technical field. The process comprises the steps of: (1) filling the mercury-containing waste hydrochloric acid in an anion exchange resin tower to carry out ion exchange, and collecting the outflow hydrochloric acid; and (2) regenerating the anion exchange resin when themercury content of the outflow hydrochloric acid is over 0.1 mg / L: filling a regenerant from the bottom of the resin tower, collecting and oxidizing the regenerated waste liquor which flows out from the top of the tower, adding a precipitant in the oxidized waste liquor for precipitation, and filter-pressing to obtain mercury mud. According to the invention, the mercury-containing waste hydrochloric acid firstly passes through the anion exchange resin and the mercury in the waste hydrochloric acid is adsorbed by the resin to ensure that the obtained outflow hydrochloric acid can satisfy the national standard and is qualified industrial finished hydrochloric acid; then the mercury adsorbed on the resin is transferred into the regenerant waste liquor for oxidization, precipitation and filter-pressing to obtain the mercury mud which is sold to the manufacturers on demand as a product, and the filtrate is retreated via the anion exchange resin and then discharged under the standard.

Description

technical field [0001] The invention belongs to the technical field of chemical industry, and relates to a recovery and treatment process of mercury-containing waste hydrochloric acid, in particular to the removal and recovery of mercury in waste hydrochloric acid, a by-product of calcium carbide polyvinyl chloride production. Background technique [0002] In the production of polyvinyl chloride, acetylene gas-phase method is used to produce vinyl chloride, that is, activated carbon is used as the carrier, mercury chloride is adsorbed as the catalyst, and acetylene and excess hydrogen chloride are subjected to gas-phase addition reaction in a converter equipped with a catalyst. The reaction temperature is 160-180 ℃. Therefore, the synthesized crude vinyl chloride contains excess hydrogen chloride and sublimed mercuric chloride. Most domestic chlor-alkali enterprises use activated carbon adsorption to remove mercury chloride. Crude vinyl chloride gas removes most of the merc...

AI Technical Summary

Problems solved by technology

At present, although China attaches great importance to the prevention and control of mercury pollution, the existing methods generally have problems such as poor treatment effect or high treatment cost.

However, with the strengthening of national environmental protection management, if chlor-alkali enterprises cannot properly handle the by-product hydrochloric acid and mercury in acidic water, the survival and development of enterprises will inevitably be affected.

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