Environment-friendly steel pickling waste liquor treatment system and method for producing PFC (Polymerization Ferric Chloride) through electrochemical process

Abstract

The invention discloses an environment-friendly steel pickling waste liquor treatment system and a method for producing PFC (Polymerization Ferric Chloride) through an electrochemical process, and relate to the technical field of environment protection. The system comprises a heat exchanger, a pretreater, a purifier, a primary polymeric kettle, a secondary polymeric kettle and an exhaust purifier, and is matched with corresponding electrodes, a filter, a reaction circulating pump and a vacuum pump at the same time. On the basis of the electrochemical process, steel (hydrochloric acid) pickling waste liquor (ferrous chloride) is subjected to oxidation polymerization reaction through a different compound electrode potential difference under a certain direct voltage so as to produce a PFC flocculating agent. The exhaust purifier comprehensively treats and recycles waste gas produced by the method, recycled hydrogen gas is combusted to heat treating fluid, and recycled sodium chlorate and sodium hypochlorite carry out oxidation polymerization on the pickling waste liquor, so that the system is safe without adding hazardous chemical substances and producing secondary pollutants, truly realizes zero release, and is a best project with environment protection and recycling economy.

Description

technical field [0001] The invention relates to the technical field of green environmental protection circular economy, in particular to an environmental protection treatment system for producing PFC by electrochemical method of steel pickling waste liquid and an environmental protection treatment method for producing PFC by electrochemical method of steel pickling waste liquid. Background technique [0002] Polyferric chloride (also known as basic ferric chloride, referred to as PFC) is a new type of inorganic polymer iron flocculant; because of its fast floc formation speed, high particle density, low dosage, and high COD and BOD removal rate High, suitable for a wide range of PH and other advantages, so it is widely used in the treatment of domestic sewage and industrial sewage. [0003] At present, many iron and steel production and processing units in my country have used the hydrochloric acid pickling process (because of the high efficiency, simplicity and thoroughness...

AI Technical Summary

Problems solved by technology

[0007] The above pickling waste liquid treatment and utilization systems all use chemical reactions to oxidize and polymerize the waste liquid, and all of them need to add corresponding hazardous chemicals. The reaction conditions are harsh and the extraction efficiency is low; there are relatively large safety and environmental protection risks, and the cost is also high.

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