washing out membrane as I type.

[cjf12]

This membrane was used and nasty when i got it. Wish I could afford a new one but I have spent close to 20g to boil this year and have told myself no more money.
When i first fired it up running spring water i only got about .8 gpm at 125 psi. That was as low as i could get it with valve wide open.
I started to soap wash it and have since got it to run at 75 psi with 1.91 gpm both pumps running.
I shut off hp pump and it reads about 2 psi and i am running about .2 gpm permeate.
I am going to let it run another hr and then rinse with 200 gal of permeate.
Anyone think this membrane is junk? Good? Never ran one to have any clue to what my benchmarks should be.

[Bricklayer]

Did you bring the wash water up to 113?
You can let them membrane soak in the soap also. Over night.
0.8 permeate is normal flow for cold sap on a 4x40. But not warm wash water.
Your soap washing too so flow rates are a little off when running soap.
Give it a good scrub with soap.
Crank it up to 200 psi with cold permeate after rinsing with 100 gallons and post results.
You should be getting over 1.25 or 1.5 gpm permeate at 200 + psi.
I'll check what my benchmark was for my membrane. But I think it was 4-1 at 200 psi with cold permeate.
So that means at 200 psi I was getting 4 gallons concentrate to 1 gallon permeate.

[cjf12]

Sounds like it should be allright. Thats exactly what happened. I did get it up to about 111. Had to heat permeate on a turkey fryer. My pumps would not warm wash at all. It actually crept down slowly. As soon as i switched to rinsing with cold permeate it went back to .8 at 125 psi. 200 psi. Was around 1.2. Looking forward to enough sap to try it out now.
Just figuring on running it through and check the permeate for sugar content. Rinse well with permeate when done. Should I be looking or doing anything in particular?
I have 3 325 gallon tanks on my trailer plumbed together. I am figuring on running one through ro and recirculating that tank untill it hits ??? Percent. Then starting the second tank doing the same then finally the third following with a rinse.

Thanks for all your help through this bricklayer.

[JoeJ]

"Crank it up to 200 psi with cold permeate after rinsing with 100 gallons and post results.
You should be getting over 1.25 or 1.5 gpm permeate at 200 + psi.
I'll check what my benchmark was for my membrane. But I think it was 4-1 at 200 psi with cold permeate.
So that means at 200 psi I was getting 4 gallons concentrate to 1 gallon permeate."

When you do your benchmark for the membrane, the instructions for my machine stated to set the PSI at 200, run the machine until the water heats up to 75 degrees, then check your flow and record the flow rate for daily comparison. If you have more than one membrane, you should have separate flow meters for each membrane to check the individual flow rates. Then as you do your daily bench mark, you can notice when the flow drops enough (10-15%) to need to a citric acid wash.

Joe

[cjf12]

Do most machines have a flow meter on both sides of discharge? May have to add that for next year. I also have a procon hp pump. It will not raise temp at all. Am I using to much wash solution? I mixed up about 25 galllon. Heated it by adding permeate heated on a turkey fryer burner till it reached almost 112.
Any problems if I make more permeate from spring water and run permeate through at the temp it is to get a benchmark? As long as its consistent temp shouldnt matter is what i am thinking.

[Bricklayer]

You should have a flow meter for permeate and concentrate. And recirc if your RO has it.
Some RO's as JoeJ said have flowmeters for each membrane. I think flowmeters on each membrane would be beneficial on a parallel membrane setup. But membranes plumbed in series it wouldn't

[JoeJ]

Do most machines have a flow meter on both sides of discharge? May have to add that for next year. I also have a procon hp pump. It will not raise temp at all. Am I using to much wash solution? I mixed up about 25 galllon. Heated it by adding permeate heated on a turkey fryer burner till it reached almost 112.
Any problems if I make more permeate from spring water and run permeate through at the temp it is to get a benchmark? As long as its consistent temp shouldnt matter is what i am thinking.

If you are adding heated water, you should be checking the PH several times as you go along, especially when you get nearer to the 112 end temperature.

If you have tested your spring water and the analysis shows that the spring water is low in minerals (especially iron and manganese) and is on the low end of hardness then you could use the water. Othewrwise you are just going to foul your membranes with minerals.

Joe