Circuit board is an assembly base to complete the connection of basic level components and other electronic circuit parts. The products are assembled into a module with specific functions. The electronic industry is developing rapidly. As one of the foundations of the electronic industry, circuit board products are increasing, and the circuit board waste water is also increasing. Liyuan environmental protection takes you to know how to carry out the wastewater treatment process of PCB production.
For the treatment of PCB waste water, several streams of water should be divided for preliminary pretreatment before comprehensive PCB waste water treatment.
1. wastewater containing silver and nickel can be pretreated by Fenton oxidation + coagulation flocculation sedimentation, and the treated wastewater is discharged into the regulating tank of comprehensive wastewater;
2. treatment of recyclable wastewater: for copper plating wastewater and wastewater containing heavy metals, corresponding chemical reagents can be used to precipitate and filter out recyclable resources;
3. the acid-base etching wastewater can be used as neutralizing wastewater for wastewater treatment;
4. the complexing wastewater can be treated by coagulation and sedimentation after adding demulsifier and oxidizing agent to the cyanide containing wastewater. The pretreated wastewater will be comprehensively discharged into the comprehensive wastewater regulating tank, and then enter the subsequent physicochemical treatment + biochemical treatment after adjusting the water quality and quantity.
The physicochemical treatment can adopt the iron carbon micro electrolysis reaction method to reduce the pollutant concentration and some heavy metal ions in the wastewater through oxidation-reduction reaction; Fenton oxidation method can strongly oxidize the wastewater, dissolve the non biodegradable organic matter and phosphorus content, and improve the biodegradability of the wastewater; The combination of upflow anaerobic reaction and contact oxidation method is used in biochemical treatment to ensure the residence time of sludge, reduce the biological load of anaerobic reactor, improve the treatment efficiency of wastewater, reduce the amount of excess sludge, greatly reduce the concentration of wastewater, and the treated wastewater can be discharged after reaching the standard.
If the concentration of organic matter in the wastewater is too high, the standby reaction tank can be used for neutral catalytic oxidation, ozone oxidation and other processes for advanced treatment to ensure that the wastewater meets the standard.