Suspended solids, colloids, organic matter, microorganisms and other particles contained in the inlet water of the reverse osmosis system attach to the RO membrane surface, deposit pollution, or the ion accumulation of chemical ion components on the membrane surface due to concentration polarization and other factors. Phenomenon such as the formation of chemical scales after the solubility product is larger. Severe pollution means that the single-stage pressure difference after pollution is more than 2 times the single-stage pressure difference value at the initial stage of system operation, the water production of the reverse osmosis system has dropped by more than 30%, or the weight of a single reverse osmosis membrane element exceeds the normal value by more than 3 kg. Happening.
Although the design of the reverse osmosis system will have a certain degree of surplus to ensure that in an emergency, the water production or desalination rate of the reverse osmosis system will not be reduced, and the pressure difference of the reverse osmosis system will increase, resulting in insufficient water supply and causing safety in production. Threats, but in fact, it is precisely because of the existence of these surpluses that sometimes hidden faults cannot be manifested in time, which may eventually evolve into heavy pollution of reverse osmosis membrane elements.
In the pollution control of reverse osmosis, the most fundamental measures are the control of the design, manufacturing and installation process of the water treatment system with reverse osmosis as the core, the selection of various consumables of the reverse osmosis system, and the control of operation management level. A good grasp of these aspects plays a vital role in the safe and healthy operation of the reverse osmosis system.
Of course, when the reverse osmosis system is seriously polluted, the first measure to be taken must be to analyze the cause of the pollution, find a solution to the pollution, and clean the reverse osmosis system in the shortest possible time through appropriate means, because with time The extension means that the difficulty of cleaning is reduced.
As a deep filtration means, reverse osmosis membrane elements will inevitably leave colloids, microorganisms, impurity particles and insoluble salts on the surface. Therefore, reverse osmosis devices used in various fields will inevitably be put into use. , In the end all need to be cleaned, but the length of the cleaning cycle is different. However, as a means of reverse osmosis system cleaning and maintenance, impact sterilization and regular protection, on-line cleaning is powerless when faced with heavy pollution of reverse osmosis membrane elements. At this time, off-line cleaning of reverse osmosis membrane elements is required.