The uf membrane module has the functions of sterilization, turbidity removal, residue removal, and water purification. It can effectively remove the suspended solids of fine sand and rust, and intercept Escherichia coli, flagellates, and various bacteria. Various microbial species, such as humic acid, humus and other biological macromolecular organic compound agents. uf ultrafiltration membrane is widely used in the field of sewage treatment and water purification due to its advantages of high packing density, large reasonable total membrane area, high pure water flux, simple actual operation, and easy cleaning.
1. Types and common problems of cleaning uf membrane module
a. The number of times of cleaning depends on the corresponding operating standards (working time, total flow of feed, total flow of permeation) and the actual physical properties of the liquid to be handled. Inorganic salts and their iron, insoluble organic compounds or microbial chemicals will foul the membrane during normal operation. Precipitation accumulates on the surface of the diaphragm, causing effluent damage.
b. The flow rate of the recoil force is positively related to the working pressure. The higher the working pressure during the entire cleaning process, the higher the permeation flow rate of the cleaning liquid into the treatment tank. At the same time, the entire cleaning process is not transformed into filtered water.
c. Generally, if the uf membrane module must be cleaned organically, a 12% sodium hypochlorite solution should be used to solve the difficulty. Aiming at the obvious environmental pollution blockage that cannot be eliminated by using this aqueous solution.
d. Washing chemistry Sodium hypochlorite is an oxide used to remove the scale of organic compounds on the membrane, and the sodium citrate-based cleaning solution is used to remove the scale of inorganic compounds on the ro uf membrane.
e. The chemical Chinese medicine preparations required by the detergent must fully consider the concentration value of the storage solution, the main purpose, the cleaning concentration value of the design scheme, the chemical flow rate and the total amount required. Other washing chemicals are likely to be incompatible with the membrane. If you use non-approved organic chemical detergents, any coverage of the uf membrane module will be invalidated.
f. Be very careful when solving the problem of washing chemicals, and wear a face mask when solving the problem of organic chemical Chinese medicine preparations. The effect of washing chemicals in eliminating actual pollutants can only be clarified through the application experience of the system. Sometimes in the continuous circulation system cleaning, in order to eliminate the mixture of environmental pollution or clear cleaning, organic chemical Chinese medicine preparations may need to use different types of cleaning fluids in the entire process.
2. Storage of uf membrane module
Before use, the maintenance liquid is generally infiltrated for sealed storage to avoid the shrinkage of the wet film after it dries, the shrinkage of the film pores, the destruction of the membrane structure engineering, and the reduction of water flux.
a. Short-term storage: When the ultrafiltration membrane is suspended from use, it should be sterilized and backwashed once, add 15ppm (ml/L) fungicide to the backwashing water, and then close the water valve, discharge valve and regulating valve to maintain tightness and sterilization Effect.
b. Long-term storage: If the ultrafiltration membrane is out of service for a long time, perform disinfection and back-cleaning first, then introduce the maintenance solution, and then store it in a sealed container.