1. Clean the water source:

A. Reverse osmosis product water - optimal

B. softened water turbidity is less than 1mg/L, SDI is less than 5, residual chlorine is less than 0.1mg/L

C. filtered water is the worst. It is not recommended.

2. Coordination agent

Chemicals and water sources to ensure uniform mixing should be repeatedly confirmed before cleaning the pH value and temperature of the cleaning solution is appropriate.

3. Cleaning operation

1) The cleaning fluid was injected into the reverse osmosis equipment at the operating pressure of 1/2 and 40~60 PSI of normal cleaning flow, and the water retained in the membrane vessel was removed. And drain off part of the cleaning fluid just beginning to prevent the cleaning solution from being diluted.

2) In normal cleaning, the pressure control criterion for cleaning system is to use the best pressure when the system can hardly produce pure water because the appropriate cleaning operation pressure can minimize the possibility of re-accumulation of foreign matter on reverse osmosis membrane surface.

3) Then stop the pump and turn off the valve, so that the membrane components immersed in the cleaning solution, soaking time for about an hour. If membrane fouling is serious or cleaning is difficult to remove the pollutants, the soaking time of the process can be properly extended. In order to ensure the temperature of the cleaning solution when soaking for a long time, the method of combining repeated circulation with soaking can also be adopted. Generally speaking, the temperature of the cleaning fluid should be kept at least above 20 C and below 40 C. Proper temperature of the cleaning fluid can enhance the cleaning effect. Please note that the cleaning fluid with too low temperature may precipitate during the cleaning process. When the temperature of the cleaning fluid is too low, the cleaning should be arranged after the temperature of the cleaning fluid is raised to a more appropriate temperature.

4. Cleaning key

First of all, the water stored in the pressure vessel is discharged. Then, the concentrated water and the produced water from the cleaning process are circulated to the cleaning tank, and the temperature of the cleaning solution is kept stable. Before starting cycle cleaning, it is necessary to confirm whether the temperature and pH value of the cleaning solution have met the standard. And the turbidity of the reflux cleaning fluid was confirmed: if the reflux cleaning fluid has changed color or turbidity, the cleaning fluid should be prepared again; if the pH value of the reflux cleaning fluid changes more than 0.5, it is better to adjust the pH value or replace the cleaning fluid.

In the chemical cleaning of the system, the general operation method is: first of all, the pressure vessel to be cleaned with low flow (1/2 standard cleaning flow) cycle cleaning for 5-15 minutes, and then the medium flow (2/3 standard cleaning flow) cycle cleaning for 10-15 minutes.

5. Flow control

Flow control of each reverse osmosis pressure vessel during cleaning

8 " membrane element: 7.2-12m /h

4 " membrane element: 1.8-2.5m /h

6. End cleaning:

After the immersion of the cleaning solution is finished, the cleaning can be finished in 20 to 60 minutes with standard cleaning flow. Then the reverse osmosis membrane module is flushed with the same volume of reverse osmosis product water, and the flushing water is discharged into the sewer.     After the cleaning is confirmed, re osmosis equipment can be run again. We suggest that at least 15 minutes after the chemical cleaning and re-operation of the system, the product water should be discharged, and the product water quality of the field system should be confirmed after careful chemical analysis, and then the system output water from the operation of the system should be put into the product water tank. In addition, in the use of a variety of medicines for cleaning, in order to prevent chemical reactions between chemicals, in each cleaning before the product water side of the best drainage should also be clean.

7. Multistage reverse osmosis:

Classification of cleaning, to prevent the first stage was washed out of the contaminated sediment and re-flow into the next stage, the formation of secondary pollution.

8. Microbial contamination:

The bactericidal solution allowed by the membrane manufacturers can be used for sterilizing and cleaning the membrane system, and the operation mode is the same as before. Please note: rinse thoroughly after sterilization, so as to avoid taking the disinfectant into the product water.

More inquiries pl contact

KHN water treatment equipments Co., Ltd.                             www.khnwatertreatment.com