Method for treating high-salt ammonia nitrogen wastewater and comprehensively utilizing fluorine-silicon resources

Abstract

The invention relates to a method for treating high-salt ammonia nitrogen wastewater and comprehensively utilizing fluorine-silicon resources. The method is characterized in that high-salt ammonia nitrogen wastewater mainly comprises the following components in percentage by mass: 1) 4%-20% of ammonium chloride or / and ammonium sulfate; 2) 5%-25% of sodium chloride or / and sodium sulfate; the ammonium chloride or / and ammonium sulfate component of the high-salt ammonia nitrogen wastewater is added into sodium hydroxoide, and is subjected to low-temperature evaporation by an ammonia nitrogen treatment system to recycle ammonia water; the recycled ammonia water reacts with hydrofluosilicic acid to generate ammonium fluoride and a byproduct white carbon black; the wastewater subjected to ammonianitrogen treatment reacts with ammonium fluoride, aluminum chloride or aluminum sulfate to obtain cryolite and a byproduct ammonium chloride or ammonium sulfate; and the byproduct ammonium chloride or ammonium sulfate is returned to the ammonia nitrogen treatment system to subject to low-temperature evaporation to recycle ammonia water. The method has the advantages that: ammonia nitrogen and salt in wastewater are sufficiently utilized by fluorine-silicon recycling to produce cryolite, so that content of ammonia nitrogen and salt in high-salt ammonia nitrogen wastewater is remarkably reduced, waste is changed into things of value, and economic benefits are improved.

Description

technical field [0001] The invention relates to a technology for the treatment of high-concentration salt-containing ammonia-nitrogen wastewater and the resource utilization of fluorine and silicon to produce sodium fluoride and co-produce white carbon black, and is especially suitable for the treatment and resource utilization of AC foaming agent wastewater. Background technique [0002] High-concentration salt-containing ammonia nitrogen wastewater is a common industrial wastewater, which is difficult to treat with existing technologies. For example, AC foaming agent produces a large amount of high-concentration saline ammonia nitrogen wastewater, the main components include sodium carbonate, ammonium chloride or / and ammonium sulfate, sodium chloride or / and sodium sulfate. AC blowing agent wastewater is a high concentration of NH 3 -N, high-concentration inorganic salt, high-concentration CODcr wastewater. Its main hazards are: (1) cause eutrophication of water body; (...

AI Technical Summary

Problems solved by technology

However, the process of this method is relatively complicated, the treatment cost is high, and the salt is not recycled and reused.

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