Shandong Jinshuanglian Machinery Co., Ltd.
Tel: +86-536-6357556 +86-536-6355711
Painting wastewater treatment equipment and technology
Painting wastewater mainly from the pre-degreasing, degreasing, table transfer, phosphate, passivation body pretreatment step; cathodic electrodeposition process and the coating, spray paint processes, automotive painting wastewater containing resins, surfactants, heavy metals ion, pigments and other pollutants, in particular electrophoretic wastewater, wastewater painting complex composition, high concentrations of poor biodegradability. Painting wastewater treatment mainly sub-quality treatment, coagulation and sedimentation, flotation, sand filtration and other processes for coating wastewater.
Feature 1, painting wastewater treatment
1) many kinds of painting wastewater treatment, water quality varies due to the materials used, there are a variety of formulations only degreaser, paint types is more.
2.) emissions without the law, in addition to part of the washing water continuously overflow emissions, waste water or waste coating line concentrated mostly intermittent emissions.
3) water quality and quantity changes, no rules to follow.
2, painting wastewater treatment issues to consider: Water automobile painting line coating process depends on a variety of wastewater, it should be in-depth investigation, the sources of pollution do detailed analysis on the basis of carefully designed. The design should pay attention to the following questions:
① Xu car loaded waste water quantity and quality changes, some wastewater treatment works in the design of water quantity, water quality equalization and quality pretreatment inadequate attention, resulting in unstable operation of the system can not even run properly.
② Automobile Painting Wastewater poor biodegradability, Biochemical should hydrolytic acidification - biological contact oxidation or SBR law, should ensure adequate biochemical time.
③ because phosphorus demanding reaction conditions, the phosphorus-containing waste mixed with other waste water is generally difficult to effectively remove, it should phosphorus wastewater pretreatment alone.
④ should clean production point of view, assist in the production and technical personnel to improve production technology, improved coating material formulation, strengthen production management to reduce pollutant emissions.
Physicochemical process wastewater oil paint, polymer resin, pigments, titanium dioxide under the effect of surfactants, solvents and various additives can be in the form of colloids stably dispersed in an aqueous solution. Metal salts or metal salts into the water after the polymer can be formed floc positively charged groups. They can and emulsified oil or polymer resin potential, complete destabilization process; adsorption of destabilization can be emulsified oil, polymer resins, pigments, such as titanium dioxide by adsorption bridging role. Therefore, the coagulation treatment can effectively remove automotive painting wastewater oil, polymer resin, pigments, and titanium dioxide. Anionic surfactants can be partially removed by coagulation treatment, but a non-ionic surfactant and solvent, various additives, etc. are difficult to remove by coagulation treatment, COD formed from them need to be removed by adsorption or biological treatment . It found that pre-treatment of wastewater is a high concentration of phosphorus-containing wastewater. Engineering practice shows that the phosphorus-containing wastewater treatment lime has a high removal rate, low running costs, is one of the phosphorus-containing wastewater treatment method is currently the most effective high concentrations.