Help updating a sigle 4" post ro

[cjf12]

I bought a used homebuilt ro I used this year with moderate success. The setup is this-
3/4 hp centrifugal pump to 2x20 prefilter to 330procon with a 1 hp pump. Goes to membrane on bottom comes out with failing digital gpm on permeate side only and needel valve on discharge. I have since added a flowmeter sight.

That is it. Plain jane as they come. Problem being is the membrane was passing sugar. I do believe it is from poor storage and cleaning from previous owner. I am going to rwplace it with an mes (thats allready whats in it) and contemplating adding another membrane.
Question. Is. What do i do to do it? I Have read tons on here and still feel like i know enough to be dangerous. Little confused on recirculating pumps.

Anyone have some time to help me make this better for next season. Hoping to.double taps from about 300 to at least 600.

[Bricklayer]

Fairly simple.
leave the first membrane the same. But where it comes out the top of membrane on outer side run that to the next membrane on the outer side as the feed to the second membrane. Tee the permeate lines together and then to the flowmeter.
You concentrate line out can be teed before the concentrate flowmeter and run to a needle valve and then a flowmeter. Then to the intake of the procon pump. This is your recirc line.
The other line off the concentrate line at the teed section is then run to the main needle valve and then to a flowmeter.
No need for a recirc pump on a 4x40 system.
You could install one but it's not really necessary.
I'm not 100% sure but I think a 330 gph procon requires a 1.5 hp motor. Don't quote me on that though. Don't have the specs in front of me.

[Clinkis]

Fairly simple.
leave the first membrane the same. But where it comes out the top of membrane on outer side run that to the next membrane on the outer side as the feed to the second membrane. Tee the permeate lines together and then to the flowmeter.
You concentrate line out can be teed before the concentrate flowmeter and run to a needle valve and then a flowmeter. Then to the intake of the procon pump. This is your recirc line.
The other line off the concentrate line at the teed section is then run to the main needle valve and then to a flowmeter.
No need for a recirc pump on a 4x40 system.
You could install one but it's not really necessary.
I'm not 100% sure but I think a 330 gph procon requires a 1.5 hp motor. Don't quote me on that though. Don't have the specs in front of me.

Yup minimum 1.5 hp, I’m running a 2 hp on my 330. It was only $30 more

[Greg MacWilliam]

Try replacing the o rings before giving up on the membrane.

[cjf12]

I have not replaced them. Have checked them over really well and not blemished at all. I know that isn't always the way it works but also know that when i got the membrane it was left half soaked in sap and i bought it in june. I did wash it and all the rest. Just figured if im adding another membrane i would start off with new to know whats normal and keep that as a spare.

[cjf12]

Fairly simple.
leave the first membrane the same. But where it comes out the top of membrane on outer side run that to the next membrane on the outer side as the feed to the second membrane. Tee the permeate lines together and then to the flowmeter.
You concentrate line out can be teed before the concentrate flowmeter and run to a needle valve and then a flowmeter. Then to the intake of the procon pump. This is your recirc line.
The other line off the concentrate line at the teed section is then run to the main needle valve and then to a flowmeter.
No need for a recirc pump on a 4x40 system.
You could install one but it's not really necessary.
I'm not 100% sure but I think a 330 gph procon requires a 1.5 hp motor. Don't quote me on that though. Don't have the specs in front of me.

So that would be in series right? How do you keep the second membrane from fouling earlier than the first? Would it help if i ran parallel with only a 1 hp pump? Guessing not but trying my options.

[Bricklayer]

So that would be in series right? How do you keep the second membrane from fouling earlier than the first? Would it help if i ran parallel with only a 1 hp pump? Guessing not but trying my options.

You would probley need a larger pump to run parallel to keep enough flow over the membranes.
330 gph split between 2 membranes is 165 gph.
Might be ok but the more the better
You'll get better concentration with the series setup.
Keeping the membranes clean is just a matter of flushing real well after use on low pressure high flow or swapping places of membranes every other use. My theory anyways.
But the more flushing / washing the better to keep clean.
If your going to buy a new membrane from MES send the old one to them and get them to clean it. Might be surprised. A new seal and a pro wash might get it to 100% flow