Our country uses groundwater as the source of drinking water, and water companies mostly use basic water purification processing techniques such as coagulation, sedimentation, filtration, disinfection, and sterilization. For water resources with good water quality, basic water treatment technology can ensure the safety of domestic water. As we all know, for water quality with obvious organic pollution, the actual effect of solving the problem cannot meet everyone's requirements for the water environment. In recent years, with the rapid development of ultrafiltration technology and the reduction of uf membrane price, ultrafiltration technology has become a hot spot in the scientific research network of the drinking water treatment industry, and its applications have become more and more common.

1. Working principle of ultrafiltration membrane

Ultrafiltration technology is a kind of separation equipment that uses the pressure difference as the driving force and uses the passing performance of the membrane to realize the separation of positive ions, molecular structures and certain particles in water. The diameter of uf membrane module ranges from about 0.005 to 1 μm, which makes up the gap between the microfiltration membrane and the nanofiltration membrane.

2.The working process of uf membrane module

① The solute is adsorbed on the surface of the membrane and the wall of the microporous plate;
② The particle size of the solute is similar to the diameter of the membrane, and the solute stays in the pores, causing blockage;
③ The particle size of the solute exceeds the diameter of the membrane, and the solute is intercepted by the mechanical equipment on the membrane surface to complete the screening.
The entire process of uf membrane module usually has two methods: terminal equipment filtration and cross-flow filtration.

For source water with low turbidity and good water quality, terminal equipment is generally used to filter, which can greatly reduce the energy consumption of the processing process; for water with high turbidity and obvious environmental pollution, cross-flow filtration can also avoid the accumulation of large amounts of pollution on the membrane surface It will cause environmental pollution of the membrane and reduce the filtration performance.

3.The characteristic structure and type of uf membrane module

The cross-sectional structure of uf membrane module is different, and generally consists of a dense layer with a thickness of less than 1 μm and a good screening effect, and a support layer of a honeycomb or finger-shaped porous material with a large thickness (usually 125 μm).
At present, the common membrane components in industrial production and daily life mainly include: tube type, chamber type filter press, roll type and hollow fiber.