Fluorine-containing acidic wastewater treatment method

Abstract

The invention provides a fluorine-containing acidic wastewater treatment method comprising the following steps: 1, the fluorine-containing acidic wastewater is placed in a recovery tank and is subjected to natural sedimentation; 2, filtering is carried out, such that a filtrate is obtained; 3, a calcium hydroxide slurry is added into the filtrate, such that primary sedimentation treatment is carried out, until the pH value of the filtrate is 5-6; 4, a mixed solution of calcium hydroxide and polyaluminum chloride is added into the filtrate, such that secondary sedimentation treatment is carried out, until the pH value of the filtrate is 7-8; and 5, filtering is carried out with a microporous filter. According to the invention, a traditional process is improved. Production wastewater is first subjected to a filtering pretreatment, such that residual insoluble molybdenum disulfide and other impurities left in the wastewater are recovered; and the filtrate is treated with a calcium salt precipitation and aluminum salt fluorine-removing combined method, such that a purpose of fluorine-containing wastewater treatment is achieved. With the method, the fluorine content in wastewater is reduced to below 10mg / L, such that a discharge standard is reached.

Description

technical field [0001] The invention belongs to the technical field of industrial wastewater treatment, and in particular relates to a treatment method for fluorine-containing acidic wastewater. Background technique [0002] The wastewater produced by the molybdenum disulfide industrial production line is mainly reaction wastewater and surface flushing wastewater. The main pollutant in wastewater is high concentration of fluorine, the highest concentration of fluorine in wastewater is above 10g / L, and contains a small amount of hydrochloric acid, nitric acid and trace metal ions. If the waste water is discharged without proper treatment, it will not only cause serious pollution to the surrounding environment and groundwater sources, but also cause production fines and stop production due to environmental inspections. [0003] At present, there are several treatment methods for high-concentration fluorine-containing wastewater at home and abroad, and the common ones are adso...

AI Technical Summary

Problems solved by technology

This method can treat a large amount of F when treating molybdenum disulfide fluorine-containing wastewater - , but the fluorine content of the treated wastewater is above 15mg / L, which cannot meet the national discharge standards, and due to the addition of excessive Ca(OH) 2 It will cause the pH value in the wastewater to exceed the standard, causing the entire environmental protection to fail to meet the standard

In addition, the molybdenum disulfide wastewater is not pretreated before the wastewater treatment, so that a small amount of molybdenum disulfide remains in the wastewater, which not only wastes the production cost, reduces the recovery rate, but also causes other impurities in the wastewater to exceed the standard

[0005] Therefore, there is an urgent need to develop a method for efficiently treating fluorine-containing acidic wastewater, so as to overcome the problems of substandard treated wastewater, excessive pH value in wastewater, and large waste of production costs caused by traditional processes.

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