In the process of industrial production, many harmful foam will be produced, and anti-foam agent needs to be added. There are many kinds of anti-foaming agent, organosiloxane, polyether, silicon and ether graft, amine, imine and amide, with faster defoaming speed, defoaming time, suitable for a wider range of media, even harsh medium environment such as high temperature, strong acid and alkali characteristics. 1, the most commonly used silicon is poly (dimethyl siloxane), also known as dimethyl silicone oil. Pure polydimethylsiloxane is difficult to be used as anti-foaming agent without dispersing treatment. Has the characteristics of low surface energy and surface tension is low, so it can effectively inhibit bubbles, reduce machine wear and prolong the service life of oil, organic silicon polymer antifoaming agent does not dissolve in oil, it is through highly dispersed and stable colloidal state and distribution in oil, such as in acid oil, with the extension of time, the organic silicon type antifoaming agent will be unstable and settlement, Accumulation causes failure of defoaming performance. The mechanism of action of silicone polymer anti-foaming agent is to change the surface tension between liquid and air, so that it is not easy to generate bubbles, so the oil containing silicone polymer anti-foaming agent has poor air release. The addition of silicone type antifoaming agent is usually 2-20ppm.