Deep fluorine removal process for fluorine-containing wastewater and aluminum source fluorine removal agent

Abstract

The invention discloses a deep fluorine removal process for fluorine-containing wastewater, which comprises the following steps: an aluminum source fluorine removal agent is contacted with the fluorine-containing wastewater, so that aluminum ions and fluorine ions are complexed to remove the fluorine ions in the fluorine-containing wastewater, and the aluminum source fluorine removal agent is an Al-MOFs / graphene composite material. According to the deep fluorine removal process for the fluorine-containing wastewater and the aluminum source fluorine removal agent, a traditional lime-PAC combined fluorine removal method is abandoned, and the aluminum source fluorine removal agent is adopted for effectively adsorbing fluorine ions in the fluorine-containing wastewater, so that the fluorine ions in the fluorine-containing wastewater are stably reduced to 1mg / L or below, and therefore, the fluorine-containing wastewater reaches the discharge standard.

Description

technical field [0001] The invention belongs to the technical field of fluorine-containing wastewater treatment, and in particular relates to a deep fluorine-removing process for fluorine-containing wastewater and an aluminum source fluorine-removing agent. Background technique [0002] A large amount of fluorine-containing wastewater is produced during the manufacture of fluorine chemical products, which can easily pollute water bodies, soil and plants. Since most of the fluorine in wastewater treatment ends up in the sludge, the fluorine content in the sludge is relatively high, and it is easy to cause serious and extensive secondary pollution in the process of storage, transportation and disposal. Once such pollution to soil and groundwater is formed, it is extremely difficult to restore. Therefore, the threat and harm to the environment of fluorinated sludge produced in the process of fluorinated wastewater treatment is much higher than that of wastewater, and its reduc...

AI Technical Summary

Problems solved by technology

The process is simple and convenient, and the cost is low, but the calcium fluoride precipitate generated in the commonly used calcium salt precipitation defluorination method will wrap on the surface of the calcium salt, making it unable to be fully utilized, so it is necessary to add an excessive amount of Ca 2+ , but a large amount of calcium salt is mixed into the sludge, which not only increases the sludge production, but also reduces the purity of the fluorine-containing sludge. At the same time, the fluorine content in the treated wastewater is more than 20mg / L, which is difficult to meet the national discharge standard

Flocculation-sedimentation method tends to generate very fine particles with small specific gravity and high viscosity during the process of wastewater treatment, and it is colloidal during the sedimentation process, so separation is difficult, which not only makes it difficult for wastewater to meet the standard, but also produces sludge with high moisture content, which is difficult to recycle.

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