The organic wastewater generated during the preparation and treatment of PCB circuit boards contains a lot of nickel. The chemical precipitation method balances the water quality and quantity of the nickel-containing wastewater, then passes through a pH adjustment tank with a pH value of about 3~4. Fenton reagent is added to the oxidation tank to convert the hypophosphite in the nickel-containing wastewater into orthophosphate to complete the wastewater decomposition. The wastewater is then introduced into an alkalization tank, and an aqueous solution of calcium hydroxide is added to generate nickel hydroxide and calcium phosphate precipitates. A polymer flocculant is added, and precipitation is carried out using a high-efficiency inclined plate sedimentation tank.

Yancheng Dongtai Bizhiyuan Water Purification Co., Ltd. Industrial Wastewater Treatment Plant. After being treated by flotation equipment, the effluent indicators meet the following requirements: SS≤ 10 mg/L, TP≤ 1.8 mg/L. The SS removal rate is ≥90%, and the TP removal rate is ≥70%.