Oil-containing wastewater treatment defoaming agent is mainly used in the oil industry, iron and steel, gas workstations, mechanical industry cooling lubricants, etc., the oil cover in the wastewater makes the water lose self-purification ability, destroys the ecological balance in the water, not only endangers human health, but also affects the production of crops. At present, air flotation is the main method to treat oily wastewater, but this method has high energy consumption, large amount of flocculant and large area. Other methods, such as electrochemical method and adsorption method, also have the disadvantages of high operating cost and small scope of application.In recent years, the research on defoaming powder as oil absorbent has provided a new way to treat oily wastewater. Yu renhuan et al. examined the effects of talc dosage and particle size on the purification of oil-containing sewage by cyclone-filled flow chamber. The results showed that when the fineness of talcum powder (150g/m3 water) was 0.074mm, accounting for 81%, the oil removal rate reached 78.30%. Talcum powder had a significant oil removal effect on the cyclone charging flow device, and the oil removal rate increased by about 5% compared with that without talcum powder. Other researchers examined the effects of talcum powder on oily wastewater treatment under different conditions.The results showed that the removal rate of COD in gasoline was 97.8% and that of diesel was 81.5% under the conditions of 20g/L talc and slow stirring for 15min at 20℃. Talc is a natural hydrophobic and oil-wet mineral, which can promote the separation of hydrophobic and oil-wet particles in oil and water.