Nanofiltration membranes can retain nano-sized materials, and other characteristics determine the specific color application range of nanofiltration membranes, which can be divided into the following aspects.
1. The application of nanofiltration membrane in soft water treatment.
Because the two ions are effectively intercepted and low pressure can be operated at high water prices, the bitterness is desalinated, which absorbs a regenerative market for sodium applications. Its main advantage is that it is free of microorganisms and does not require regeneration. , Permeates water and organic matter, simple, does not take up space, etc. Moreover, it is relatively close to the method in terms of investment and price, so there is a suitable and traditional organic operation in this field.
2. The application of nanofiltration membrane in drinking water purification.
Due to the residue of water pollution, the quality experiment of the substances concerned has proved that nanofiltration membranes can remove the slightly toxic by-products, residual herbicides, pesticides, natural organic matter, natural organic matter, water quality, and sulfide produced in the disinfection process. Salt and nitrate, etc. It also has the advantages of good water quality, stability, low dosage of chemicals, small convenience, energy-saving, management and maintenance, and basically zero discharge. Therefore, nanofiltration membranes may become the preferred technology for clean purification in the 21st century.
3. The application of nanofiltration membrane on the salt in the porous surface.
In the development of salt concentration in groundwater, in areas dominated by agriculture, the water quality index is far and near, and reverse osmosis technology can be used to mine salt and other substances. But because the water recovery rate is relatively high. At the same time, the treatment of condensate is also a problem. Generally, an ion-exchange method is required to treat wastewater.
On the other hand, ion exchange resins preferentially exchange divalent and high-valent ions. If the high-priced content in the reducing solution increases the processing cost, centralized regeneration will increase the large-scale water first. High-salt salt is treated with nanofiltration membrane and then treated with ion exchange method, the treatment time can be extended by 2 to 3 times.
The solution contains a large number of inorganic salts. After the sodium ion exchange column, the inorganic ions are exchanged by chlorides. At this time, the nitrate content in the water meets the requirements of inorganic salts. Its advantages are: it can permeate nitrates, and the water recovery rate is high. This technique has been widely used in Germany.
4. The application of nanofiltration membrane in leaf treatment.
Because the residue contains a large amount of cotton, which can penetrate and absorb each other, the black wood and the agitated wood produced in the process of absorbing black wood and wood pulp are absorbed by the element and absorption method because many organic matters in peat are negatively charged and are easily positively charged. The nanofiltration membrane is destroyed instead of causing serious pollution. For example, nanofiltration membranes are used to decolor the waste liquid produced in the alkali extraction stage of wood pulping, the ribbon membrane, biomembrane and soil lignin in the waste liquid can be intercepted, and the monovalent ion ions that do not need to be intercepted can be re-excited through the membrane, The decolorization rate of the film reaches 98%.
5. The application of nanofiltration membranes in advanced sewage treatment.
Membrane filtration treatment is also an important way to realize the recycling of sewage. Its main processes include flocculation sedimentation, disinfection, and other treatment processes. The process after membrane treatment also includes membrane treatment. Both can use treated water.
Sixth, the nanofiltration membrane contains subtle applications in the treatment.
In the electroplating process and alloy manufacturing process, a lot of water is often cleaned because of the excessive copper content, such as nickel, iron, and zinc. Processed into sediments, if nanofiltration membrane technology is used, more than 90% of the part can be recovered for purification, and the real value can be reduced by 10 times so that the reduction can be reused.
Under proper conditions, nanofiltration membranes can also achieve the separation of different metal elements in the solution, such as the separation of Cd and Ni, first convert them into CdCl2 and NiCl2, and then add NaCl to form charged and uncharged complexes respectively Things. When the concentration of NaCl is 01mol/L when the complexion exists in the solution, it mainly exists in the form of CdCl2, but the nickel does not exist in the combined form. The compound is in the form of nickel ions. The positively charged NF is used to in intercept the nickel ions to let free Flow through to achieve separation between metals.
Post time: Jun-16-2021