Application and Characteristics of Defoamer in Different Wastewater Treatment
The common treatment method for papermaking wastewater is coagulation method, which has strong adaptability, simple equipment and convenient operation, but has the disadvantages of high cost and large amount of sludge production; the other method is biological method, which has no secondary pollution. , low processing costs, but can not completely reduce the content of organic pollutants. In recent years, domestic and foreign scholars have applied talc powder as a coagulant, coagulant and filter aid to treat papermaking wastewater defoamers.
The defoaming agent for oily wastewater treatment is mainly applied to the cooling lubricating fluids from the petroleum industry, steel, gas workstations, machinery industry, etc. The coverage of the oil surface in the wastewater causes the water body to lose its self-cleaning ability, destroying the ecological balance in the water, not only endangering human health, but also affecting Production of crops. At present, the air floatation method is the main method for treating oily wastewater, but the method has high energy consumption, a large amount of flocculant and a large area. Other methods such as electrochemical method and adsorption method also have high operating cost and small application range. And so on.
In recent years, some scholars have provided a new way to deal with oily wastewater by defoaming powder as an oil absorbing agent. Yu Renhuan and other factors examined the effects of talc dosage and particle size on the purification of oily sewage from a gas-filled cyclone. The results show that when the fineness of talc powder (150g/m3 water) is 0.074mm and 81%, the degreasing rate reaches 78.30%. The degreasing effect of talcum powder on the inflatable cyclone is significant, compared with the non-addition of talcum powder. The degreasing rate is increased by about 5%. There are also research scholars to examine the effect of gangue treatment of oily wastewater under different conditions.
The results showed that the talc powder dosage was 20g/L at 20 °C, and the COD removal rate was 97.8% and the diesel removal rate was 81.5% under the condition of slow stirring for 15 minutes. Talc is a natural hydrophobic and lipophilic mineral that promotes the separation of hydrophobic and lipophilic particles in oily water. Therefore, talc can be used as an oil absorbing agent to treat oily wastewater.