Membrane Question

[christensonjes]

Hi there,
I have a 75 gpd 5 stage RODI unit that I bought from you several years ago. I need a new membrane for it. Can I upgrade to the 150gpd membrane? Or would i need a new case for it. Also are there any advantages to switching to a higher membrane like less waste water?

Thanks Jesse

[kylesmoney]

You can switch to a 150gpd membrane but you have to switch the flow restrictor to a 150gpd flow restrictor

Wont produce lower waste water but be sure to get one that has a good rejection rate (like 98%)

Also make sure that you have enough water pressure for a 150gpd membrane (usually 65psi)

[David Grigor]

If you want to reduce waste water, use 2 75gph membranes in-line ( meaning waste line of #1 is the input to #2 ). This will reduce the water waste to roughly 1:1 instead the typical 4:1 ratio.

Only problem is, you need pretty high psi to accomplish this. As stated earlier 65psi would be the minimum. Otherwise you have the added expense of a booster pump.