Waste acid regeneration and resource recovery system

Abstract

The invention discloses a normal-pressure low-temperature air circulation continuous waste acid regeneration and recovery system. The system comprises an air circulation system, a heat pump system, a condensation recovery system and a freezing crystallization system, water molecules and volatile acid in waste acid liquid are separated through low-temperature air of the air circulation system, first condensation recovery is conducted through the condensation recovery system, and meanwhile waste heat of the condensation recovery system is recovered through the heat pump system to continuously provide heat for the air circulation system. The concentrated acid liquid treated by the air circulation system is introduced into the freezing crystallization system to be frozen, crystallized and filtered, and the residual liquid is finally stored in the recovery tank to be recycled. The system is applicable to treatment of waste acid solutions with any concentration, and the waste acid treatment cost is greatly reduced due to low equipment manufacturing cost required by a normal-pressure and low-temperature operating environment and waste heat recycling and circulating operation. And a good acid regeneration effect is achieved.

Description

technical field [0001] The invention relates to the technical field related to waste acid regeneration and resource recovery, and specifically relates to a waste acid regeneration and resource recovery system. Background technique [0002] The pickling treatment of steel is used to remove the oxide scale on the surface of the cold-rolled sheet blank, that is, the hot-rolled sheet. After retrieval, it was found that the invention of application number CN201910465444.5 discloses a waste acid recovery method for treating steel pickling waste liquid. The method is used to process pickling waste liquid obtained by cleaning steel with hydrochloric acid. HCl gas is introduced into the solution, and water or dilute hydrochloric acid is added to the pickling waste liquid at the same time, so that ferrous chloride tetrahydrate crystals are precipitated in the pickling waste liquid, and the recovered supernatant is a hydrochloric acid solution that can be reused for steel cleaning. At...

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Problems solved by technology

At present, there are two treatment methods for the waste acid produced in the pickling process of steel in this field: one is to transfer it as hazardous waste to a qualified third party for treatment, and the other is to use evaporation equipment for evaporation; if it is transferred to a third party that exists The problem is that there may be environmental risks in the leakage of waste acid. In addition, the transfer cost is as high as several thousand yuan per ton, which puts a relatively large cost pressure on the enterprise; if the traditional evaporation equipment is used for evaporation treatment, the investment in equipment is large (the material of the equipment is 2205 Duplex steel, Hastelloy, etc.), the operating cost is also high; or it is necessary to add a large amount of alkali for neutralization and then use 316L or titanium material as evaporation equipment; processing increases the difficulty

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