The Technical Definition of Filter Membrane
The membrane filtration is a solid-liquid separation technique. It filters water with the membrane pore and filters out the impurities without having any chemical changes. Because the membrane pore is very small, there still remain some technical problems.
The filter membranes are classified according to the sizes of raw water particles. From large to small, the membrane pores are divided into Micro-Filtration membrane, Ultra-Filtration membrane, Nano-Filtration membrane, and Reverse Osmosis membrane. Specifically, the pore size of the MF membrane is above 0.05 um, or above 1,000 molecular weight. It is used for filtering coliform and macromolecular organic matter.
The pore size of the NF membrane is between 100 and 1,000 molecular weight. It is used for filtering trihalomethane, peculiar smell, chromaticity, pesticide, and dissolved organic matter. While the pore size of the RO membrane is tens of molecular weight. It is used for filtering table salt and inorganic salt.
On the whole, the materials for making the filter membrane mainly include Poly Tetra Fluoro Ethylene, Polyvinylidene Fluoride, Nylon, and so on.
Furthermore, there is no need to use chemical treatment of flocculation and chemical treatment of flocculation when using a filter membrane. The most important feature of the filter membrane is that it only needs the pressure to separate the solid from the liquid.