Cleaning and maintenance methods are as follows:
1, the physical cleaning method
The simplest physical cleaning method is the use of low-pressure high-speed membrane into the water through the water for 30 minutes, which can make the membrane permeability to a certain degree of recovery, but a long time, water permeability is still declining, can also be mixed with water and air The fluid scoured the membrane surface for 15 minutes at low pressure, and it was effective to wash the membrane contaminated with organic matter in this manner at the initial stage.
2, chemical cleaning methods
① citric acid solution, in high pressure or low pressure, with 1% -2% aqueous solution of citric acid on the membrane continuous or re-washed, this method of Fe (OH) 3 pollution has a good cleaning effect.
② Ammonium citrate solution, citric acid solution by adding ammonia or dubbed a different PH value of the solution can also be added in the ammonium citrate solution HCL, adjust the PH value to 2-2.5, for example, 190L deionized water, dissolved 277g of citric acid amine, adjust the pH value of the solution with HCL 2.5, with this solution in the membrane system cycle cleaning 6 hours, the effect is very good, if the solution heated to 35-40 ℃, the cleaning effect is better, the solution The cleaning effect of inorganic pollution is very good, but the cleaning time is longer.
 ‘¢ plus enzyme detergent, with enzyme detergent film, organic pollution, especially for protein, oil and other organic pollution is particularly effective, if the 50 â “ƒ -60 â” ƒ cleaning effect is better, the general operation of 10 days Or half a month after the enzyme with 1% enzyme detergent at low pressure on the membrane once washed, because the use of enzyme detergent concentration is low, so the time required for a longer impregnation.
④ concentrated brine, re-do the membrane of limb pollution using brine cleaning is effective, this is because the high concentration of salt can reduce the interaction between the colloid, colloidal coagulation to promote the formation of micelles.
⑤ water-soluble emulsion, oil and iron oxide used to clean the film is very effective pollution, the general cleaning 30-60 minutes.
⑥ hydrogen peroxide solution, for example, 0.5L, 30% H2O2 with 12L of deionized water, and then clean the membrane surface, this method is particularly effective for organic pollution.
⑦ sodium hypochlorite and formaldehyde solution, for bacterial contamination, depending on the membrane to take different treatment measures, the fragrant polyamide membrane can be 1% by weight of formaldehyde solution cleaning, and often to reverse osmosis exudate concentrate to maintain 0.2 -0.5mg / l of residual chlorine, to prevent bacterial growth.
 ‘¢ oxalic acid and EDTA solution, the film on the metal oxide precipitation, with oxalic acid and EDTA solution is better.
However, the country was home integration to remind you that in the use of reverse osmosis exudation, the temperature drop will cause a decline in water production, which is a normal phenomenon, in addition to periodic cleaning, in each start, It is best to run low pressure for a few minutes to remove the reverse osmosis in the concentration of water, and drain them, do not enter the next level unit.
