Treatment technology of waste water containing fluoride and ammonia nitrogen

Abstract

The invention provides a treatment technology of waste water containing fluoride and ammonia nitrogen. The technology is used for treating waste water containing fluoride and ammonia nitrogen in tantalum-niobium hydrometallurgy. The technology is characterized in that the relative volatility difference between ammonia and water is utilized; an ammonia-water separating technology in which high-efficiency distillastion is treated as the main technology core is carried out and combined with a pre-treatment technology to perform defluorination-calcium removing-strong dissolving and complexing-molecular distilling, so as to realize the removal of fluorine and ammonia; the drained water obtained after treatment reaches national primary emission standard; meanwhile, high-purity ammonia water with concentration being equal to or greater than 15% is recovered for production. According to the technology, the ammonia is recycled, so that the balance of payments of the treatment cost of the ammonia containing waste water can be achieved; the requirement on comprehensive utilization of the resource can be met; the technology brings a certain economic benefits.

Description

technical field [0001] The invention belongs to the field of waste resource treatment or metallurgy, and relates to a treatment method for fluorine-containing ammonia nitrogen wastewater from tantalum and niobium hydrometallurgy, in particular to a treatment method using defluorination-calcium removal-enhanced decomplexation-molecular distillation The combined process recovers ammonia from wastewater and makes the treated water meet the national first-level discharge standards. Background technique [0002] The fluorine ammonium nitrogen concentration in the wastewater discharged from tantalum niobium wet process, tungsten, and rare earth smelting enterprises is relatively high, and some wastewater contains NH 4 The concentration of Cl reaches above 10g / L, and the fluorine-containing ammonium nitrogen wastewater is also the main wastewater in the production process of tantalum and niobium hydrometallurgy. The discharge of high content of fluorine leads to a series of enviro...

AI Technical Summary

Problems solved by technology

The one-time investment of "ammonia distillation" is too large, the latent heat is not utilized, the energy consumption is high, and the power consumption of "blowing" is too large

[0005] 2. When the A/O method is continued, not only the investment is high, but also the floor area is large, and the requirements for the pretreated water are strict (such as NH3-N must be less than 300mg/L, fluorine must be less than 50mg/L, and the stripping or stripping method is more than 100mg/L. High-concentration ammonia nitrogen wastewater above 5000mg/L cannot meet this requirement at all, so it can only be diluted with doubled water)

[0006] 3. Although the investment and floor area of ​​the continuous chemical precipitation method are smaller than that of the A/O method, its consumption of chemicals is too large. The ratio of N:...

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