A compound flocculant for simultaneous removal of phosphorus and fluorine from electroplating wastewater and its preparation method

Abstract

The invention discloses an electroplating wastewater synchronous dephosphorization-defluorination compound flocculant and a preparation method thereof. The flocculant is prepared by compounding hydrogen peroxide, poly aluminum chloride, inorganic aluminum salt and inorganic cerium salt according to a molar ratio. The preparation method includes: fully mixing poly aluminum chloride, the inorganic aluminum salt and the inorganic cerium salt proportionally; adding water to prepare a mixed solution; adding hydrogen peroxide, and mixing well to sufficient reaction to obtain the flocculant. The defect that phosphorus and fluorine in conventional electroplating wastewater are difficult to be deeply treated synchronously is overcome, the compound flocculant has the advantages of low cost and good effect, the problem that effective treatment cannot be realized due to the form problem of phosphorus is solved, phosphate radicals and fluorine ions in a water body can be removed synchronously, and the compound flocculant is high in precipitation speed, good in treatment effect and small in amount of generated sludge and conforms to a rule of reducing solid waste.

Description

Technical field [0001] The invention relates to the field of sewage treatment, in particular to a compound flocculant for simultaneous removal of phosphorus and fluoride from electroplating wastewater and a preparation method thereof. Background technique [0002] The phosphorus index is one of the most important indexes for the eutrophication control of water bodies. When the total phosphorus content in the water body exceeds 0.02mg / L, it may cause eutrophication of the water body. Eutrophication of water bodies will seriously damage the ecological balance and affect human health. Therefore, it is necessary to strictly control the concentration of phosphorus discharged into water bodies. Fluoride is also one of the important indicators of sewage discharge control. This is because too much fluoride intake will also have adverse effects on the nervous system, endocrine and immune function, causing brain damage, Alzheimer’s and other diseases, especially for children. In other wo...

AI Technical Summary

Problems solved by technology

Among them, the calcium salt precipitation method is suitable for the treatment of high-concentration phosphorous and fluorine-containing wastewater, but not for the treatment of low-concentration biochemical tail water; the adsorption method has a certain effect on orthophosphate, but has no effect on hypophosphite; traditional The coagulant has no obvious effect on the removal of low-concentration phosphorous and fluorine-containing wastewater, and it is difficult to meet the requirements of reuse water

Phosphorus and fluorine are both inorganic anion pollutants. If they are treated separately, the sewage treatment process will be too complicated, the treatment process will be long, and the investment cost will be high, which is not conducive to the treatment of large-volume wastewater.

[0005] Chinese patent "A compound oxidant and wastewater treatment method for advanced treatment of electroplating wastewater containing phosphorus", patent application number: 201410334337.6, uses "oxidation + adsorption" to treat phosphorus in electroplating wastewater, although the treatment effect is good, but its treatment The technological process is complicated, and fluorine cannot be effectively treated at the same time, so it is not suitable for simultaneous phosphorus-containing and fluorine-containing wastewater

However, such technologies are still lacking