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Precautions When Using Nanofiltration Membrane
- Aug 13, 2018 -

Precautions when using nanofiltration membrane


RisingSun membrane offers a wide range of fine molecular weight cut-off nanofiltration membrane elements with a compact structure and reasonable surface area to volume ratio. By using different flow channels, (13-120 mil) can change the width of the liquid flow channel to adapt to various viscosity liquids. In order to meet the application of certain special industries, we can provide acid and alkali resistant, high temperature resistant and anti-pollution film products.


Precautions when using nanofiltration membrane


Nanofiltration membranes are functional semipermeable membranes that allow the passage of solvent molecules or certain low molecular weight solutes or low-cost ions. Nanofiltration is generally used to remove organic matter and pigments from surface water, hardness and radium in groundwater, and partially remove dissolved salts, and extract and concentrate useful materials in food and pharmaceutical production. So what do you need to pay attention to when using it?


1. When the PH value is greater than 10, the maximum temperature for continuous operation is 35 °C. When the influent contains free chlorine or other oxidizing substances, the oxidation performance may seriously damage the performance of the ring membrane. Therefore, it is recommended that the user pretreat. Free chlorine or other oxidizing substances are removed.


2. The membrane elements were tested for water passing through the factory and vacuum-packed in 1.0% by weight sodium bisulfite and 20 ppm isothiazolinone protection solution. In the severe cold area, 10% by weight of glycerin is added to the protective liquid as an antifreeze solution. In order to prevent the growth of microorganisms during short-term storage, transportation and system shutdown, it is recommended to soak the membrane elements with 1.0% by weight of sodium bisulfite (food grade) protection solution (formulated with RO water).


3. The membrane element should not be unsealed before it is put into use. Once it is unsealed, it should always be kept moist.


4. The water entering the membrane element should be gradually pressurized. The time to normal operation should be no less than 30-60 seconds. The flow rate of the membrane element should be gradually increased. The time to the specified value should be no less than 15-20 seconds.


5. For the first time, the system water should be discharged first, and the discharge time should be at least one hour.


6. The membrane element must be disinfected with formaldehyde for at least six hours. If formaldehyde is used within six hours, it may cause a loss of flux.


7. The back pressure of water produced at any time shall not exceed 0.03MPa. The maximum allowable pressure drop per pressure vessel is 50 psi (0.34 MPa).


8. Please use chemical agents, lubricants or protective fluids that are not compatible with membrane elements.