Electronic industry wastewater treatment method based on short-cut nitrification and denitrification

Abstract

The invention discloses an electronic industry wastewater treatment method based on short-cut nitrification and denitrification. The electronic industry wastewater treatment method comprises the steps of S1, conveying etching liquid wastewater to be treated to a calcium salt sedimentation tank for defluorination pretreatment; S2, conveying the wastewater subjected to defluorination pretreatment and the comprehensive wastewater to a biochemical regulation tank, and regulating the pH value to 7-8; S3, conveying the wastewater with the regulated pH value to a short-cut nitrification tank for a short-cut nitrification reaction, wherein the functional flora is ammonia oxidizing bacteria, ammonia nitrogen is oxidized into nitrite nitrogen, biological filler is hung in the short-cut nitrification tank, and the pH value is 7-8; S4, conveying the wastewater treated in the step S3 to a denitrification tank, and maintaining the C / N ratio at 3-4; and S5, conveying the wastewater treated in the step S4 to an aerobic nitrification tank for further carbon oxidation reaction and nitration reaction, and enabling the wastewater in the aerobic nitrification tank to flow back to the denitrification tank according to the reflux ratio of (1-4): 1. The method can greatly reduce the concentration of fluoride and ammonia nitrogen when the high-fluorine and high-ammonia-nitrogen wastewater is discharged, and achieves the purpose of deep defluorination and denitrification of the high-fluorine and high-ammonia-nitrogen wastewater.

Description

technical field [0001] The invention belongs to the technical field of wastewater biological treatment, in particular to a method for treating wastewater in the electronics industry based on short-range nitrification and denitrification. Background technique [0002] In recent years, my country's electronics industry has developed rapidly, and the etching process is one of the key steps in the production process of printed circuit boards, glass lenses, etc. The glass chemical etching process mainly includes smooth etching and matte etching, of which smooth etching Mainly use hydrofluoric acid to react with the glass surface to form soluble salts; while rough surface etching requires the addition of ammonium fluoride (NH 4 F), Formation of ammonium silicofluoride crystallites in reaction with glass and hydrofluoric acid. Since glass etching technology uses a large amount of hydrofluoric acid and ammonium fluoride (NH 4 F), resulting in high concentration of fluoride and ultr...

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Problems solved by technology

Since glass etching technology uses a large amount of hydrofluoric acid and ammonium fluoride (NH 4 F), resulting in high concentrations of fluoride and ultra-high concentrations of ammonia nitrogen in the etching wastewater, which increases the difficulty of wastewater treatment

For this type of wastewater, the existing treatment methods usually use chemical precipitation, stripping and stripping, etc., which makes the wastewater treatment cost of the sewage plant high, it is difficult to meet the effluent standard, and it is easy to cause secondary pollution

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