Once a reverse osmosis system is in operation, it should be kept as stable as possible. Each start and stop of the system involves changes in flow and pressure, which puts mechanical stress on the membrane elements. Therefore, try to reduce the frequency of starting and stopping the system when necessary, and normal starting and stopping should also be carried out smoothly. So when the reverse osmosis water treatment equipment needs to stop using normally for a period of time, how should the maintenance and repair? Stopping time is different, maintenance measures are not the same.

First, the system normal shutdown steps

      Open the water discharge valve, open the high-pressure pump bypass control valve, reduce the inlet water flow of the system, while slowly opening the thick water control valve, reduce the pressure to 30 ~ 40psi or so, turn off the corresponding dosing device, maintain this low-pressure flushing until the thick water conductivity and the inlet conductivity of the same, low-pressure flushing 5 ~ 10min, the system shutdown.

Second, shutdown 0-2 days

      Short-term shutdown can be carried out in accordance with the normal shutdown procedures, but low-pressure flushing must be carried out, and in order to prevent bacterial growth, need to be flushed every 24 hours.

Third, shutdown 2-25 days

      1. After shutdown, ensure that the pressure vessel is filled with pure water produced by R0, and close all the inlet water, thick water valves and water production valves to prevent the membrane element from drying and microbial growth;

      2. when the temperature is greater than 20 ℃, every 12 hours will need to repeat the rinse; when the temperature is less than 20 ℃, repeat the rinse every 24 hours;

      3. for surface water or water sources with high microbial contamination, the reverse osmosis system must be flushed with a solution containing 1.0% sodium bisulfite prepared from R0 produced water. if the membrane elements are soaked with this solution at the same time, the effect will be better, and the repeat rinsing cycle will be extended accordingly;

      4. during the system shutdown, the temperature is maintained at 5 ℃ ~ 45 ℃, low temperature is conducive to the preservation of membrane elements, but at the same time should prevent the system from freezing ice.

Long-term shutdown for more than 25 days

      1. refer to the normal shutdown procedures, and product water with low-pressure flushing system, and at the same time a chemical cleaning and sterilization treatment, after cleaning with R0 low-pressure water flushing system, until the concentrated water conductivity and the inlet water conductivity is consistent;

      2. use reverse osmosis produced pure water to formulate the protective solution containing 1.0% sodium bisulfite, relying on the chemical cleaning system cycle flushing membrane elements, exclude the air in the pressure vessel, the membrane element is completely immersed in the protective solution, to prevent the membrane element from drying out, close all the inlet water valve, concentrated water valve and produced water valve, to prevent air from entering to make the protective solution ineffective;

      3. check the PH value of the protective fluid every week, when PH<3, need to replace the protective fluid in time;

      4. During system shutdown, keep the temperature between 5℃~45℃, low temperature is favorable for the preservation of membrane elements, but at the same time, the system should be prevented from freezing.