ZSF series dissolved air floatation sewage treatment machine is of steel structure. Its working principle is: the air is pumped into the pressure dissolved air tank and forcibly dissolved in water under the pressure of 0.m5pa. In the case of sudden release, the air dissolved in the water is precipitated to form a large number of dense microbubbles. In the process of slow rise, the suspended solids are adsorbed to reduce the density of suspended solids and float upward, The purpose of removing SS and CODcr is achieved. The product is suitable for sewage treatment of petroleum, chemical industry, papermaking, leather, printing and dyeing, food, starch and so on.