Spraying paint wastewater comes from washing water while wet paint spraying. In the painting room, the paint and organic solvent in the air are transferred to water and form wastewater. The wastewater contains a large amount of paint particles. The water quality depends on the paint, solvent and additives used. The following describes the wastewater treatment of typical automobile painting/coating.
For car manufacturer, the coating of automobile and relates parts is one of the main source of sewage. If not dispose properly, it will cause serious pollution to the environment. The waste water discharged from paint workshop is divided into two types. One is bath waste water, which is intermittent discharging. Another is washing wastewater, which discharges continuously. After processing by pp filter press, the moisture can be reduced from 99% to 75%~80%.
Technically and economically, it is feasible to treat coating / painting wastewater by following steps: wastewater separation treatment, coagulation & precipitation, air flotation and sand filtration etc... And it turns out, for this technology, the removal rate of heavy metals, SS and oil is more than 90%, and for CODCr, the data can over 80%. Finally, after the treatment by plate frame filter press, the utilization rate of wastewater will be significantly improved.