initial XLE-4040 wash options

[SilverLeaf]

Lots of good info here on the 'Trader (as usual!) but as everyone has different membranes I'm having a hard time figuring out what to do for the initial wash of my new homemade RO, which has a Dow XLE-4040 membrane. Would like thoughts from anyone who uses this membrane.

1) How many gallons to run through? I'm seeing anywhere from 200 (seems do-able) to 1,000 (goodness, thats a lot!)
2) I don't have any permeate (yet) so, what water to use? My options:

a) Well water that has been run through a softener. My well water is actually ok soft-wise but has high iron which is why we run it through the softener for the house. Would the extra sodium from the softener harm the membrane?

b) city water that has been left sitting to let the chlorine out. I have access to city water but it'd be a royal pain to cart it.

c) sap???? It seems some people swear by using sap instead of water. But no way no how do I want to lose perfectly good sap. Ok maybe 50 gallons, but 200-1000? That's way too much of a hit for my (small) operation. Am I being obstinate here?

[1efddd]

I don't know if it was right or wrong but I broke mine in with well water and then flushed the crap out of it with the permeate that I made from the well water. I ran 100 gal of sap through it a week ago and it worked great.

[SilverLeaf]

I don't know if it was right or wrong but I broke mine in with well water and then flushed the crap out of it with the permeate that I made from the well water. I ran 100 gal of sap through it a week ago and it worked great.
How much well water did you run through (before the permeate)?

[JoeJ]

Lots of good info here on the 'Trader (as usual!) but as everyone has different membranes I'm having a hard time figuring out what to do for the initial wash of my new homemade RO, which has a Dow XLE-4040 membrane. Would like thoughts from anyone who uses this membrane.

1) How many gallons to run through? I'm seeing anywhere from 200 (seems do-able) to 1,000 (goodness, thats a lot!)
2) I don't have any permeate (yet) so, what water to use? My options:

a) Well water that has been run through a softener. My well water is actually ok soft-wise but has high iron which is why we run it through the softener for the house. Would the extra sodium from the softener harm the membrane?

b) city water that has been left sitting to let the chlorine out. I have access to city water but it'd be a royal pain to cart it.

c) sap???? It seems some people swear by using sap instead of water. But no way no how do I want to lose perfectly good sap. Ok maybe 50 gallons, but 200-1000? That's way too much of a hit for my (small) operation. Am I being obstinate here?

200 gallons of water for the initial flush should be enough.
A) From what i have been told by a membrane expert, do not use any water high in iron. The iron will plug the membrane. Soft water with no manganese or iron. Not certain about the salt but I was told that a
water softener would work to produce acceptable water.
B) City water straight from the tap is not OK because of the chlorine. But Maple Flats suggest drawing the city water into a tank and letting it sit for at least 3 days to dissipate the chlorine
C) Again according to the membrane expert, do not use sap. You will just start to plug your membrane before you even use it to concentrate

Joe

[wnybassman]

I ended up visiting a larger local producer and bumming some permeate to get me started. I really wanted to use the right stuff right from the get go.

[SilverLeaf]

I'm small, but in my neck of the "woods" I'm the largest local producer for miles in any direction, so getting some permeate from someone else is off the table for me. I'm starting to lean towards using the water out of my softener. Its a lot of work to haul city water and let it sit!

For the first rinse do I just run the whole thing through at low pressure so that it all comes out the permeate line? Or do I crank it up a bit and force it through the membrane at some point?
Also - do I need to do an acid wash before I use it or is this rinse good enough?

[wnybassman]

Any local breweries near by? I have heard they could be a source of pure water as well.

[Clinkis]

I’ve used my well water every year to flush my membranes at the beginning of the season without issue. These membranes are designed to purify imperfect water so a little well water shouldn’t hurt them. Just stay away from Chlorinated water and should be fine. If there is any kind of accumulation of impurities on the membrane from your well water then a proper washing and rinsing should remove them.

[Tweegs]

I run the xle-4040’s and used softened well water for the initial rinse.
If memory serves, the instructions for these membranes states to rinse them for 30 minutes prior to use.
Since these membranes were developed for desalinization, what little salt remaining in the softened water shouldn’t hurt them a bit.

I ran 200 gal of softened water through with the needle valve wide open for the first pass.
Used the same water and put between 150 and 200 psi on them for the second pass.
Used the permeate made from the second pass to do a final rinse (needle valve open).

[SilverLeaf]

I ran 200 gal of softened water through with the needle valve wide open for the first pass.
Used the same water and put between 150 and 200 psi on them for the second pass.
Used the permeate made from the second pass to do a final rinse (needle valve open).
Oh perfect, this is helpful! Do I correctly assume then that you don't do any acid wash or anything as part of this first cleaning?

[Tweegs]

No need to do a wash on new membranes.
The wash cycle is intended to remove fouling.
The initial rinse is to purge the membranes of preservative.