RO Issues

[DavidM]

I have a Ginsan RO system that is about 20 years old. It began producing water at a trickle so we checked flow controls, water pressure, regulators, water filter. Finally put new membranes in and it worked great again.
After 2 months, it was back to a trickle. Installed another set of new membranes, worked great. 2 months later it is back to a trickle.

Water softener and charcoal filter are good, test chlorine and hardness, no issues there.

Does anyone have any ideas?

I don't know what could cause a membrane to clog that quickly. We are using Filmtec XLE membranes


David

 

[Toms PTcarwash]

Where is your reject water set? If you have it set to low, or shut off, you will foul membranes very quickly.

 

[Greg Pack]

IIRC, An XLE requires very little pressure, around 100 psi to make. If your pressure it too high it might be forcing too much through the membrane. I usually ignore the pressure gauge, try to look at the flow meters and adjust to make sure that that there is more reject than permeate water. That may not be the "correct" way, but I reuse my reject so I'm not worried about wasting water and my membranes seem to last 5 years plus.

 

[MEP001]

I had a customer years ago with a very similar problem. It ended up being a very fine silt that would go right through a 5 micron filter. I put in a .35 micron, the finest I could find, and it solved the issue. The prefilter had to be changed about once a month or it would stop flow to the system.

 

[DavidM]

I believe we are rejecting about 1.5 gallons per gallon.

I will check the feed pressure and maybe look for a finer inlet filter.

Thanks for the ideas, I will report back after I check it out.

David

 

[cantbreak80]

IIRC, An XLE requires very little pressure, around 100 psi to make.

Greg Pack might be on to something...XLE Info

Dupont also has some specifics regarding Initial Start Up Sequence

 

[WaterTech]

What is your water source?
Have you taken a SDI test?