In the ultrafiltration membrane screening process, the pressure difference between the two sides of the membrane is used as the driving force, and the ultrafiltration membrane is used as the filter medium. Under a certain pressure, when the raw liquid flows through the membrane surface, many fine micro-micro membranes are densely covered on the surface of the ultrafiltration membrane. The pores only allow water and small molecules to pass through and become permeate, and the substance in the original solution having a volume larger than the pore diameter of the membrane surface is trapped on the liquid inlet side of the membrane to become a concentrated liquid, thereby purifying, separating and concentrating the raw liquid. the goal of. There are about 6 billion 0.01 micron micropores on the wall of the ultrafiltration membrane per meter length. The pore size only allows the passage of water molecules, beneficial minerals and trace elements in the water. The smallest bacteria in the world are known to have a volume of 0.2. Micron, so bacteria and colloids, rust, suspended matter, sediment, macromolecular organic matter, etc., which are much larger than bacteria, can be intercepted by the ultrafiltration membrane, thereby realizing the purification process.