As we all know,ro uf membrane has the functions of sterilization, removal of residues, purification of water, etc., but it should be cleaned on time after long-term use, otherwise the bacteria will be easily blocked.
1. Cleaning type and common problems of ro uf membrane
(1). The frequency of cleaning depends on the special working conditions and the specific chemical properties of the liquid being processed. Carbonate and its iron, insoluble organic compounds or biotechnological components will foul pvdf uf membrane during normal operation. During the working process, the precipitate accumulates on the surface of uf membrane module, causing water pollution.
(2). The recoil flow rate is positively related to the working pressure. The higher the working pressure in the cleaning process, the higher the soaking flow rate of the cleaning liquid into the treatment tank, and it will not be converted into filtered water during the entire cleaning process.
(3). Under normal circumstances, if ro uf membrane needs organic chemical cleaning, a 12% sodium hypochlorite solution (NaOCl) saturated solution should be used to solve the difficulty. The serious environmental pollution blockage cannot be removed with this saturated solution.
(4). Sodium hypochlorite is a kind of oxide, used to remove the scale of organic compounds on the membrane, and sodium citrate-based cleaning solution is used to remove the scale of inorganic compounds on the membrane.
(5). The organic chemical Chinese medicine preparation required by the cleaning agent requires full consideration of the concentration value of the storage solution, the purpose, the planned cleaning concentration, the flow rate of the chemical agent, and the estimated total number required.
(6). Be especially careful when dealing with chemical cleaning problems. When solving the problem of organic chemical Chinese medicine preparations, masks, plastic covers and rubber gloves should be worn.
2. Storage of ro uf membrane.
PVDF uf membrane generally enters the maintenance liquid for sealed storage to prevent the membrane pores from becoming smaller after the wet membrane is dried, destroying the membrane structure and reducing the water flux.
(1). Short-term storage: When stopping use (less than 10 days), sterilize ro uf membrane and backwash the problem, add 15ppm (ml/L) pesticide fungicide to the backwash water, then close the water valve, discharge valve and regulating valve to keep Tightness and actual sterilization effect.
(2). Long-term storage: If the use is terminated for a long time (more than 10 days),uf membrane module should be disinfected and backwashed first, and then the maintenance solution should be introduced and sealed for storage.