1. If any of the following situations occurs during the operation of the device, chemical cleaning must be carried out immediately. (Under standard conditions, namely pressure 1.5MPa, water temperature 25 ℃, recovery rate 75%).
When the total pressure difference of the device increases by 0.15~0.2MPa compared with the initial stage of operation.
When the desalination rate of the reverse osmosis plant drops by 3 percentage points compared with the last cleaning.
When the total water production of the device has decreased by more than 10% compared with the last cleaning.
Even if the above three situations have not occurred, it should be cleaned once every 3 to 6 months.
2. Matters needing attention:
Pickling formula is used to remove CaCO3 scaling and heavy metal pollution during cleaning, and alkali cleaning formula is used to remove organic pollution.
The maximum temperature of the cleaning solution is 30°C, the maximum pressure is 3.5kg/cm², and the cleaning time for each period is 45 minutes. The solution is prepared with reverse osmosis water or ion-free water, and the solution should be mixed evenly.
After cleaning according to the specified time, rinse with filtered water after the security filter (5 microns). The flushing time is generally 30 to 60 minutes, and the reverse osmosis outlet water is drained.
After confirming that the flushing is complete, it is best to put it into normal operation immediately, and the time from chemical cleaning to re-starting operation should not exceed one day.
Clean the first section, remove the tube plugs of each cleaning return port, replace the tube connectors, and close the concentrated water outlet valve.
Open the outlet valve of the cleaning pump, start the cleaning pump, and adjust the return valve of the cleaning pump to an output flow rate of 80 ㎡/h (the component to be cleaned), and the gauge pressure of the pressure gauge is not greater than 0.4MPa, cycle for 45 minutes, and the cleaning temperature is not greater than 30 ℃.
Clean the second section, and close the total return port of the first section of cleaning liquid.
Repeat the second action.
After the cleaning is finished, the valves are transferred to the normal operation state, the concentrated water and product water discharge valves are opened, and the valves of the cleaning device are closed.
The reverse osmosis plant performs low-pressure flushing.
Prepare the membrane preservation solution by cleaning the reverse osmosis plant.
Close the concentrated water outlet valve. Open the cleaning solution inlet and cleaning solution outlet valves, and open the cleaning permeate outlet valve.
The operation steps are the same as the second step of the cleaning method, but the total pressure difference of the cleaning pump flow device is limited to not more than 0.4MPa.