Waste sulfuric acid recovery method

Abstract

The invention discloses a waste sulfuric acid recovery method. The method comprises the following steps: 1, connecting three tower liner PTFE funnel drainage tubes of a raw drying tower, a primary absorption tower and a secondary absorption tower to one drainage duct (10); 2, guiding the drainage duct to the middle lower portion of the body of a slightly-negative pressure final acid tower (6), opening a pore on the tower body, and recovering the acid obtained after sampling to the final acid tower (6) through utilizing a position difference and the slightly-negative pressure; and 3, arranging rain covers to funnels at all tower sampling ports respectively, comprising a drying tower sampling acid recovery funnel and a rain cover (7), a primary tower sampling acid recovery funnel and a rain cover (8) and a secondary tower sampling acid recovery funnel and a rain cover (9) for avoiding rainwater from entering the final acid tower. The method has the advantages of simple rectification and reformation, less one-time investment, only need of the addition of one cast iron tube and three simple rain covers, reduction of the processing cost of acidic wastewater, reduction of the waste acid discharge amount, waste acid reuse, energy saving, environmental protection, fully recovery of the sulfur element to a system, and making cost reduction.

Description

technical field [0001] The invention belongs to the field of chemical production, and in particular relates to a method for recovering waste sulfuric acid in the sampling of the acid production section in the pyrite acid production process. Background technique [0002] In the pyrite acid production process, there is a 24-hour online acid concentration analyzer in the acid production section that feeds back to the sulfuric acid central control room for adjustment at any time. Changes severely corrode the equipment. Generally, manual sampling is used for 4-8 hours to analyze each of the three towers. During the analysis process, the sampling bottle needs to be cleaned 3 times. The waste sulfuric acid is directly poured through the sampling funnel and then drained to the special acid discharge line. Processing after collection. Due to the water absorption of concentrated sulfuric acid, it absorbs moisture in the air during the pouring process and becomes dilute sulfuric acid,...

AI Technical Summary

Problems solved by technology

Due to the water absorption of concentrated sulfuric acid, it absorbs moisture in the air during the pouring process and becomes dilute sulfuric acid, which intensifies the corrosion of the sampling funnel. The funnel and drainage tube are easy to corrode and leak if the time is long. The mild one will corrode other equipment, and the severe one will damage the operation people are also at risk

Finally, the stainless steel funnel is improved, but it will leak with time. Finally, the tetrafluoro material can solve the leakage problem, but it cannot be recycled. The waste acid discarded by cleaning the sampling bottle during the sampling process is wasted, and the waste acid needs to be treated before it can be used. emission

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