Method for quality-divided purification treatment of fluorine-containing wastewater

Abstract

Belonging to the technical field of water treatment, the invention particularly relates to a method for quality-divided purification treatment of fluorine-containing wastewater. According to the invention, the idea of wastewater reuse and quality-divided purification is adopted for optimization of washing pickling method to achieve the purpose of waste control by waste, and also the high-cost investment of HF and the like can also be reduced. The method recycles the newly generated chlorine-containing wastewater and fluorine-containing wastewater in a non-discharge mode, and by controlling theHCl adding amount, the pH, the reaction time, the temperature and the stirring speed in the purification process, and comprehensively considering the operability and economic benefits of industrial production, the purity of fluorine-containing sludge reaches 90% or above of the HF preparation level. Because of no additional raw material, under the condition of not increasing the project investment, the treatment load of F- in the wastewater is reduced, the CaF2 purity of the sludge is improved, and the resource utilization of solid waste is realized.

Description

technical field [0001] The invention belongs to the technical field of water treatment, and in particular relates to a method for treating fluorine-containing waste water by means of separation and purification. Background technique [0002] With the rapid development of my country's photovoltaic industry, the market share accounts for more than 50% of the world, the potential hidden dangers caused by the large-scale development of the photovoltaic industry in the early stage are gradually exposed, and it is difficult to contain the phenomenon. A large amount of hydrofluoric acid is used in the production process of solar panels, which leads to high concentrations of F-, total nitrogen, total phosphorus, COD, etc. entering the natural environment, and also produces a large amount of inorganic fluorine-containing waste. Fluoride-containing wastewater will produce a large amount of fluoride-containing sludge after treatment, of which calcium fluoride accounts for more than 40%...

AI Technical Summary

Problems solved by technology

The calorific value of fluorine-containing sludge is low, and incineration is generally not used for disposal. If co-processing, there will be corrosive risks, and general incineration and disposal units will not take the initiative to accept it; landfill disposal also has risks. Some studies have shown that using HJ / T557-2010 Waste Leaching Toxic Leaching Method Horizontal Oscillation Method", to simulate the leaching of pollutants under the scouring and immersion of solid waste in surface water or groundwater, using HJ / T300-2007 "Solid Waste Leaching Toxic Leaching Method Acetic Acid Buffer Solution Method" to simulate landfill Environment, after solid waste is landfilled, F- is more likely to leach under acidic conditions, and is soaked by leachate. The results show that the fluoride leaching concentration in the landfill environment exceeds 100mg / L. Currently, wastes with inorganic fluoride (HW32 ) The construction and entry conditions of hazardous waste landfills with disposal qualifications are extremely high, and landfill disposal is not the most ideal disposal method. In addition, affected by the operating license, there are few units that can dispose of HW32