Treatment method and system for purifying phosphogypsum yard penetrating fluid

Abstract

The invention discloses a treatment method and system for purifying phosphogypsum yard penetrating fluid, and the treatment system for purifying the phosphogypsum yard penetrating fluid is adopted toperform the following steps: (1) introducing the phosphogypsum yard penetrating fluid into a primary neutralizing slot, adding quick lime or slaked lime, controlling the pH value of the neutralizing slot, adding a flocculating agent, and pumping the mixture into a primary settling tank; (2) introducing clear liquor on the top of the primary settling tank into a secondary neutralizing slot, addingquick lime, slaked lime or sodium hydroxide to regulate the pH, adding the flocculating agent, and pumping the mixture into a secondary settling tank; (3) pumping secondary clear liquor into a membrane treatment unit; and (4) pumping penetrating fluid treated in step (3) into a biochemical treatment unit, thereby completing the treatment process. The treatment method provided by the invention is good in effect and low in cost; and various indexes of the treated penetrating fluid can reach the primary standards of Comprehensive Sewage Discharging Standards (8978-1996).

Description

technical field [0001] The invention relates to the technical field of chemical sewage treatment, in particular to a treatment method and system for purifying permeate from a phosphogypsum storage yard. Background technique [0002] Phosphogypsum is the waste residue discharged by phosphorus chemical enterprises. Prepare 1 ton of phosphoric acid (with 100% P 2 o 5 total) to produce 4.8-5.0 tons of phosphogypsum (dry basis). At present, the world's output of phosphogypsum has exceeded 280 million tons, and my country's output has exceeded 50 million tons. Any discharge will cause environmental pollution. Most enterprises use open-air storage yards to stack them. Phosphogypsum is a moist fine powder, 95% of the particles are smaller than 0.2mm, the free water content is 20% to 30%, and it contains a small amount of harmful impurities such as phosphorus, fluorine, organic matter and silicon dioxide. It is acidic and its pH value is generally below 4.5. . Long-term stockpil...

AI Technical Summary

Problems solved by technology

However, with the development of the enterprise, due to various factors, the permeate cannot be reused or cannot be fully used, and it will face the problem of discharging the permeate after it is technically treated to meet the standard.

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