Rapid separation of emulsified oil from water by demulsifier for metal polishing wastewater

Due to the different polishing AIDS and formulations used by each company, the polishing wastewater is troubled by brighteners, cleaning agents and surfactants. Therefore, the wastewater has high oil content and COD content, and the concentration of suspended solids is also large. In addition, the materials of metal polishing are mostly stainless steel, copper and aluminum alloy, which leads to the composition of such wastewater Complex. So how to treat the metal polishing wastewater?

In order to meet the national discharge standard, the treatment of metal polishing wastewater must be combined with (physical method + biochemical method). First, we can carry out a pilot test. Take 100ml of wastewater, adjust the pH value of wastewater to about 8 by adding liquid alkali, and then add 3 / 1000 of metal polishing waste water demulsifier. After stirring for several seconds, the wastewater quality changes obviously. After Zui, add polyacrylamide anion Ions (1% aqueous solution), stirring for a few seconds, standing precipitation, both the suspension and water separation state, clear supernatant. The removal rate of COD in wastewater is as high as 90%. The pollutants such as surfactant and emulsified oil in water are separated and flocculated.

Demulsifier

Combined with the original equipment and process of the plant, the process of coagulation, air flotation, biochemical, sedimentation and membrane filtration can be adopted. After the sewage is pumped into the coagulation tank, the process of our pilot test is as follows: adjusting pH value with liquid alkali → adding demulsifier for metal polishing wastewater → adding polyacrylamide, and then entering the air flotation tank (degreasing). After Zui, the water is very clean and the water quality is clear, The treated sludge can be dried by filter press and then transported out for treatment.

After treatment by equipment and chemicals, COD, SS, waste oil, phosphorus and other substances and suspended solids can achieve the treatment effect. (Note: different water can be designed and adjusted according to the actual situation of wastewater).