Improved treatment method of acidic waste water containing heavy metals

Abstract

The invention discloses an improved treatment method of acidic waste water containing heavy metals; the treatment method comprises the following processes and steps: (1) blast aeration: carrying out blast aeration oxidation treatment on mine acidic waste water containing the heavy metals in an aeration tank with the aeration time of 30-50 min, wherein an aeration system adopts a ceramic-prepared microporous aeration head; (2) pH adjustment: carrying out pH adjustment and neutralizing treatment with a lime emulsion, and adjusting and controlling the pH value to be 8.0-8.5; (3) flocculation treatment with the flocculant dosage of 8-12 mg / L and the hydraulic retention time of 25 min-40 min; (4) standing precipitation: allowing most of bottom mud subjected to standing precipitation in a precipitation tank to synchronously return to a water pool and a flocculation tank, and scraping the rest part to a mud bucket by a mud scraper and discharging, wherein the backflow ratio of backflow slurry of the bottom mud is (8-10):1; and (5) physical and chemical adsorption treatment. The method can greatly reduce the consumption amount of a neutralizing agent and a flocculant, the amount of eventually produced sludge is substantially reduced, the content of the heavy metal elements in the sludge is increased significantly, the concentration treatment of the sludge is facilitated, the production process is simple, and the production cost is low.

Description

technical field [0001] The invention belongs to the technical field of sewage treatment and utilization, and specifically relates to a treatment process for acidic wastewater containing heavy metals, so that the treated acidic heavy metal wastewater can reach the discharge standard of "Comprehensive Wastewater Discharge Standard" (GB8978-1996), and is especially suitable for mine dumping Application of field acid heavy metal wastewater treatment. Background technique [0002] Due to its persistence, the heavy metal pollution and hazards produced in the mining process have attracted more and more attention from the whole society. The leaching of heavy metals from dumps is the main way of heavy metal pollution in mines. During the dumping process of the dump site, because the ore body is often accompanied by a variety of heavy metals and sulfide minerals, during the mining process, these minerals form a solution of sulfuric acid to ferric sulfate under the combined action of ...

AI Technical Summary

Problems solved by technology

The treatment method of the invention has a good treatment effect, but the treatment process is complicated and the treatment cost is high

[0005] In order to solve the disadvantages of large consumption of neutralizing agent and large amount of sediment in the LDS process and the high reflux ratio of the sediment and the high moisture content of the remaining sediment in the current HDS process, this process has carried out in-depth research on the original process and many field tests, and successfully Develop a treatment process for high-concentration sediment reflux to effectively treat acidic heavy metal wastewater

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