Membrane Separation Technology
Membrane Separation Technology
Zhengzhou Toper Industrial Equipment Co., Ltd. membrane separation technology is under certain pressure, so that the different components of the mixed solution selectively technical methods through a porous polymer film. Separation process is: put some pressure on different parts of a mixture of molecular weight group when flowing through the membrane surface, water and low molecular weight solutes through the membrane will, while the polymer solutes can not pass through the membrane and is trapped, Different parts of the group in order to achieve separation and concentration. Zhu “Health and membrane pore size of the membrane separation itself relevant, pore size, the lower the molecular weight of the trapped component. Membrane separation technology is a new, faster development of wastewater treatment technologies, and its features are: high separation efficiency, capable of separating useful materials, can be recycled wastes; membrane separation process is a physical process, the process does not occur phase change material ,; membrane separation process at ambient temperature, the phase transition does not occur, to be separated without destroying the substance for separation, concentration of heat-sensitive substances; device is simple, small footprint, easy operation, design and control automation, has developed into a important industrial unit operation technology.
According to the size of the diameter of the pores of the membrane film can be divided into: microfiltration (MF), ultrafiltration (UF), nanofiltration (NF) and reverse osmosis membrane (RO). According to membrane material can be divided into organic film and the film is an inorganic film, an organic film price is relatively low, but is easy to pollution and degradation of life is short; inorganic film is mainly a ceramic membrane, higher prices, high temperature, strength, acid base. Properties and application of various films are as follows:
Microfiltration. Usually as a pretreatment unit other membrane microfiltration membrane pore size in millimeters, when as a pretreatment unit, easy to be waste in fines and colloidal material clogging the membrane pores, when the paper industry wastewater usually occurs within a few minutes congestion, frequent backwashing. However, if the waste has been pretreated (eg sand filter), it will not happen soon clog.
Ultrafiltration. Suitable for removing colloidal substances, coagulation matter and macromolecules can separate all the bacteria, can be used directly for paper machine white water treatment, ultrafiltration membrane average pore size of 0.05gm.
Nanofiltration. Suitable for separation to remove large molecular weight cations (e.g. calcium, magnesium) and the relative molecular weight greater than 300g / mol (nanometer) molecules, can be used to soften the water.
Reverse osmosis. Capable of separating monovalent ions, can be used to produce pure water and desalination processes. In the papermaking wastewater reuse for the end of the closed loop can be reduced back to the water conductivity
