RO Membrane Damage

We have a 3000 lph RO plant.

We recently changed the first membrane due to high TDS, and once again the new membrane, which is in first, got damaged within one month.

TDS rise in the entrance of the first membrane. What is the cause?

• Every pressures is normal.
• Feed presure 9.5kg
• Feed water reject comes around 5200 lph
• Product water flow 3000 lph.

Taxonomy

• Treatment Methods
• RO Systems
• Reverse Osmosis
• Membrane Technology
• Membrane Filtration
• Total Dissolved Solids (TDS)

21 Answers

1. Generally the first membrane (feed end membrane) fouls with high SDI. i.e. fouling with particles. The reject end membrane foul with scaling potential materials (Carbonate, silicate, phosphate, sulphate scales). Biofouling can happen at any location but high potential is towards reject end due to low flux.

   Detailed study is required to diagnose the problem properly for prevention. 

2. Dear Mr. Syam,

       Reverse Osmosis is not appropriate for desalination, using very expensive equipment, expensive high pressure pumps, and expensive membrane. The  problem you are facing will be repeated very frequently. We are presenting worldwide a far better process relying on Room Temperature Evaporation imitating the natural process availing rain water. Our process is very economical in equipment, maintenance and operation; at least no membranes at all. our website naturalseawaterdesalination.com.

3. Hi

   What is the nature of observed damage? Is it deposition of salts on the membrane or mechanical failure (For example telescoping) of the membrane?

4. Flowback may have a solution to your high TDS issue - please fill out report form and email back to james@flowbacksolutionz.com then we can discuss in detail 

5. Are you dozing anti-scalant? Anti-scalant avoids deposition and damage to RO Membrane

   Rajendrakumar V Saraf

6. Low operating pressure,high TDS,cold feed water,damaged seal etc could b reasons for RO membrane damages.

7. There is a solution, RO membranes have limited function although it is most successful , there are new technologies  to address the consistent change of membranes

8. Hello,

   I would advise to check your pre-treatment performances for suspended solids and chlorine (or any oxydant) removal if any. SDI and chlorine tests can be performed before opening the pressure vessels. Feed water quality can also be double check depending on its origin. In any case for further help, please specify the following and do not hesitate to contact Lenntech BV team: feed water source and analysis, PID or process steps details, RO arrangement, if available operating data. 

   Good luck

   Florent

   1 Comment

   1. In addition oil and grease must also be checked in feed water.

9. The problem is not clear. It requires a detailed study of the plant to find the rootcause of the problem.

   Atleast the feed water analysis, daily log sheet, plant design details are required to narrowdown the root cause.

10. See my posting in LINKEDIN on the topic ECG for reverse osmosis plant - MATRIX advanced real time remote monitoring system. This may help you. 

    K.V.RAMAN

11. Your feed water reject seem high - is that normal?

12. how do you know it is the first RO element damaged? is the salt rejection low from the first RO membrane? or is TDS of RO permeate high for whole vessel? if it is latter, most like it is not RO element damage rather than O ring leakage. need to provide more detail information about your problem. 

13. Dear Arvindj,
    
    It is not easy think in a reason with this data.
    It will be better if you describe your system and post the lab analysis.

    Regards,
    
    Orlando D. Gutiérrez Coronado

14. 3 reasons, 1) check pretreatement, sdi high, silica content in raw water high, or biological fouling of membrane... Call +919824088850 for further discussion and free guidance

15. Undoubtly your biological pretreatment is not working, or you have high silicate influent concentration and or a deficient antiscalant stage; because you use low pressure many mistakes I can find assuming you are treating brackish water.

    1. you just have

16. Whats your feed water TDS

     

    1 Comment

    1. 1100 ppm

17. You should perform an SDI test, and re-exam the situation when you have the results for at least three separate feedwater sample. If need help on this contact  (no charge for guidance).

18. Have you examined the seals?  When the membrane was replaced, did you inspect or replace the seals at the front end of the pressure vessel?  High TDS indicates that the source water is entering the product pipe, in my humble  opinion.

19. Did you inspect the membrane?  Was it still intact?  Did you see evidence of fouling (from suspended solids and colloids, not mineral scale)?  If the membrane was still intact, have you checked for chlorine in the feed water?

    2 Comments

    1. How to check chlorine content in feed water

    2. Tnkx for ur replies.

       I have replaced all seals and o rings but there is no improvement.i have doubt in the water flow rate.the pump is pushing around 8000 lph in tham product water around 3000 lph aand waste water around 5200 lph.is there any solution for that.is bye pass is necessary

        

20. Have you checked the pre-treatment? Function of cartridge filter? We made the experiance that the first membrane is often mechanically damaged by partiales.

    1 Comment

    1. Every filters are new

21. That is bilogical induced. You can stop that by installing an Atlantium Hydro Optic UV system. For more Infos come direct to me

    jorge@atlantium.com