MF and UF Technology

Fundamental Principles of Ultrafiltration (UF) and Microfiltration (MF)

Ultrafiltration and microfiltration are the processes of liquid phase separation under the driving force of static pressure difference. In principle, there is no essential difference, and they are the sieve separation process. Under a certain pressure, when a mixed solution with a polymer solute and a low-molecular solute flows through the membrane surface, a solvent and a low-molecular solute (such as an inorganic salt) smaller than the pore of the membrane pass through the membrane to be collected as exudate; The polymer solute (such as an organic colloid)larger than of the pores of the membrane is intercepted by the membrane and recovered as a concentrate. A membrane separation process can intercept the molecules having a molecular weight of 500 or more, less than 106 is called ultrafiltration; a membrane separation process can intercept only larger molecules (generally referred to as dispersed particles) is called microfiltration. 

Ultrafiltration and microfiltration technology can effectively remove particulate matters, including microorganisms such as cryptic bacteria, Giardia, bacteria and viruses. It is also possible to reduce disinfection by-products by reducing the concentration of the disinfection by-product precursor and limiting the amount of oxidant required during the disinfection process. However, the removal rate of organic matters in water is very low, only below 20%. Ultrafiltration and microfiltration are used in a wide range of applications and can be adapted to treat different water qualities.