Ro membrane element is the core of household water purifiers, and is currently the world's highest technology for water filtration and purification. At present, domestic reverse osmosis membrane manufacturers is mainly dependent on imports, and domestic technology cannot be produced. Domestic ro membrane element can only be bought from foreign membranes. A good RO membrane generally has a service life of 2-3 years, and the TDS value in the north is relatively high. , Affect the service life. However, the cost of RO membranes is relatively high, and user replacement costs are high and troublesome.

1. Cleaning method of ro membrane element

As we all know, the pretreatment process design of the reverse osmosis membrane 3 reverse osmosis system has removed the pollutants brought by the raw water as much as possible, but not all of them, so the pollution of the reverse osmosis system is very common. Fortunately, most pollutants can be removed by regular chemical cleaning. As long as the pretreatment works normally and there are no reasons that are difficult to control, such as changes in raw water quality or unavoidable microbial contamination, the frequency of cleaning can be as low as possible. Sometimes operating errors will cause membrane pollution, such as high recovery rate or abnormal dosing system.

The contaminated water produced by ro membrane element will decrease, the desalination rate will decrease, and the pressure difference between the inlet and the concentrated water will increase. Membrane cleaning can make some acid and alkali chemicals, and the temperature of the membrane cleaning solution is up to 45°C. Many pollutions, especially slime, accumulate over time and are compressed and thickened. This will increase the difficulty of cleaning and greatly extend the cleaning time. If the symptoms meet the following characteristics, immediately clean the membrane element: the standardized water production is reduced by 10-15%, the salt rejection rate is reduced by 0.5%, and the pressure difference △P is increased by 15%.

2. Ro membrane element cleaning prescription and other equipment

(1). Cleaning kit: Chemical cleaning kits are usually made of PE or FRP, which can withstand the PH range of 1-12.
(2). Cleaning heating device: The cleaning temperature should be as high as possible, such as 20-40°C. Do not perform chemical cleaning below 10°C, because the cleaning efficiency is very low, so a heating device is required during cleaning.
(3). Cleaning agents: strong acids and alkalis are used for cleaning, so it is very important to choose chemicals. Sometimes, improper selection of agents will cause membrane pollution or even damage.
(4). Cleaning pump: cleaning is an acid and alkali resistant pump, with a flow rate of 12-15m3/h and a head of 20-30 meters.

(5). Corresponding pipes, valves and pressure gauges must be installed during cleaning. Connect the water outlet of the pump to the inlet of the membrane, connect the concentrated water pipe to the medicine tank, install a ball valve before connecting it to the original water tank, and connect the medicine tank to the pump.