RO membrane question

[ddociam]

I have built two 4x40 RO machines. Last year was my inaugural year with the first one. I had a 14 gpm pump to feed the filter and a 150 gph Procon pump with a 1/2 horse motor. I didn't get much done very fast but I was able to separate water from sap without the evaporator. I made a few mistakes that cost me several hundred gals of concentrated sap on the floor, I consider it tuition. My upgrade for the first pump is to up the Procon to 250 gph and a 3/4 hp motor. I think that will perform better, but my new build has a two hp motor on a 330 Procon, I wondering how much more production I will get by adding a second membrane to this set up. I'm going to be processing about 500 gals a day when its going at peak. I would like to do one pass with the bigger faster unit and then RO into my head tank hoping to get plus 8% by going through the two units. Any thoughts would be appreciated. I don't think I will have a recirculating circuit but its a possibility.
Jerry

[arcticmaple8]

Ive built a few. We had 3 4x40 xle in series on a procon 330 with 2hp motor. Didnt have recirculation pump on it but worked good. You prob wont get 8% without a recirc valve puting concentrate back into feed pump. Adding another membrane or 2 is definitely worth it

[ddociam]

Thank you. Do you have any idea of per hour output on your 330. I know some of the numbers for theoretical out put but wondered how it worked for you.


Sent from my iPhone using Tapatalk

[OGDENS SUGAR BUSH]

Thank you. Do you have any idea of per hour output on your 330. I know some of the numbers for theoretical out put but wondered how it worked for you.


Sent from my iPhone using Tapatalk

you should be able to remove at least 90 gals of water per hour with your new set up

[ddociam]

you should be able to remove at least 90 gals of water per hour with your new set up

That sounds awesome. Thanks.


Sent from my iPhone using Tapatalk

[arcticmaple8]

We would get about 3gpm of permeate on raw sap starting off by the time it got to 8% it would drop in half. Ran 300psi

[maple flats]

For recirculation, you don't necessarily need another pump. My Deer Run (Ray Gingerich) RO simply has a small needle valve just before the main needle valve. The small valve controls flow in a bypass line, it goes from just before the main needle valve back to the high pressure pump input. As simple as that is, I can get 8-9% in one pass, but it does better I think if I just open that little needle valve a little bit, to get about 7% then run from my head tank back thru to get 110-12%, I can get 13-14% but it takes longer. When you run from the head tank you need to either pull from the middle elevation in the tank or stir the tank a few times because otherwise the heavier (higher sugar concentrate) will be at the bottom and the % you think you are getting will not be uniformly throughout the tank. I just stir mine, others set up so they are pulling from higher up in the tank.

[ddociam]

Maple Flats. Thanks for your help. It seems that if you put the recirculating line right in front of the high pressure pump it’s the same as putting it back in the tank. Your only bypassing the 5micron filter. Am I right? And does that make much difference?
Jerry


Sent from my iPhone using Tapatalk

[maple flats]

Right, you are bypassing the prefilter, but you are also sending a portion of the concentrate coming out of the membranes back thru the high pressure pump again. It quickly lowers the pressure reading, so as I open the recirculation needle valve slowly, I need to turn the high pressure needle valve tighter. I pretty much try to watch the concentrate flow meter and I try to keep it at 1.4 gpm, the rest is permeate, but also realize that my pump moves very slightly over 4 gpm at high pressure, as I open the recirculate valve the 2 flow meters no longer add up to slightly over 4 gpm, the difference is what is passing thru the recirculation shortcut. That line (5.16 ID I think) has no flow meter on it.
Likely the high priced RO's with a recirculate pump also have a flow meter on them.

[ddociam]

Everything you said makes sense to my limited knowledge and experience. I ordered a second membrane and ss canister. When I get it set up I’ll try a recirculation line. Thank you.


Sent from my iPhone using Tapatalk