Points to be maintained for reverse osmosis water treatment equipment: When using reverse osmosis water treatment equipment, if the unit's water production drops by 10%, if the salt permeability doubles, or the pressure drop doubles, it means that the reverse osmosis needs cleaning (However, it should be noted that a drop in temperature will also cause a decrease in water production. This is a normal phenomenon. In addition to periodic cleaning, it is best to run at low pressure for a few minutes at each start to remove the concentration in the reverse osmosis device Water and drain it, do not enter the next unit.
I. Water Quality Management Although the water treatment system is an automatic control operation, it is relatively simple when the automatic control is running. However, the most important water quality management is in the maintenance management of the reverse osmosis device operation. As a water station operator, it is very beneficial to make daily water quality management records on a regular basis to find faults and take measures.
2. Same as the water quality management, during the operation of the equipment, it is necessary to compile records of flow, pressure and water quality, and insist on operating daily reports. These records are also necessary to accumulate data, analyze the cause of the accident and take corresponding measures. Causes of unfavorable conditions and the reasons and countermeasures for the decrease in water production of reverse osmosis equipment, the causes and countermeasures for the decrease in water production quality of reverse osmosis equipment, the causes and countermeasures for the reduction in water production in reverse osmosis equipment, and the countermeasures for serial numbers The number of membrane modules is operated. Low pressure operation is performed according to the designed reference pressure. The compaction of the membrane module occurs when it is operated under conditions that greatly exceed the reference pressure. The compaction of the membrane module must be replaced. The operating temperature of the membrane module must be reduced. Running at higher recovery rate When operating at higher recovery rate, the amount of concentrated water will decrease, so the concentration rate of water in the membrane module will increase, resulting in a serious degradation of the feedwater quality.
2.Chemical cleaning method
① Citric acid solution, under high or low pressure, use 1% -2% citric acid aqueous solution to continuously or cyclically rinse the membrane. This method has a good cleaning effect on Fe (OH) 3 pollution.
② Ammonium citrate solution. Add ammonia water or a solution with different pH value to the solution of citric acid. You can also add HCL to the solution of ammonium citrate to adjust the pH value to 2-2.5. For example, dissolve in 190L deionized water. 277g of citrate amine, adjust the pH value of the solution to 2.5 with HCL, use this solution to cycle clean in the membrane system for 6 hours, the effect is very good, if the solution is heated to 35-40 ¡ã C, the cleaning effect is better, the solution Pollution and cleaning effect on inorganic matter are very good, but the cleaning time is longer.
As the osmotic pressure of the feed water increases, the amount of permeated water decreases. In severe cases, salt scale will be precipitated on the membrane surface. Water-producing metal oxides and contaminants must be adhered to the membrane surface according to the designed recovery rate. Daily low-pressure flushing operation. The pressure difference of the reverse osmosis water treatment equipment will be improved to improve the operation of the pretreatment device. Mixing of the oil content of the membrane cleaning membrane components for management. Note that the oil must not enter the feed water exchange membrane module table. The cause of the decline in the quality of the produced water of the reverse osmosis device and the countermeasures for the serial number are the countermeasures for the raw water. Damaged replacement membrane element The short circuit of the “brine seal” of the membrane module caused concentration diffusion on the membrane surface, which deteriorated the water quality. Replacement of the membrane module ring leakage increased the recovery rate of the replacement ring. As the feed water concentration in the membrane module increased, the quality of produced water deteriorated.