% after first pass?

[cjf12]

What is everyone getting out of the 4 inch membrane on the first pass? Mine is a MES 4040 single membrane.
I just ran 355 gallon of sap to concentrate down to 275 on the first pass. I hardly noticed a change in % sugar. I am now recirculating through and am finally up maybe 1/2 a %.
Im dissapointed. Should i be.
I knew the membrane may not be good. Should i bite it and get a new one?

[Haynes Forest Products]

Are you checking the permeate to see if you passing sugar? Because if your reducing your liquid that much and not increasing your sugar content more that .5% something is funny.

[cjf12]

Reads 0%
I have a digital Milwaukee i was using but im struggling with its accuracy. Went back to my sight one and im just now at 2.5. Up from around 1.9

[Bricklayer]

What pressure are you running. And what gpm's are you getting from concentrate and permeate.

[cjf12]

250 psi. Started out at 1.25 gpm removed and is now down to 1.17

[Bricklayer]

Refresh me on your RO.
How many membranes
What kind of pump etc.

[cjf12]

Sounds similar to yours without bells and whistles. Procon hp pump. Single membrane mes 4040. Only a psi gauge at needle valve and at prefilter. And only a flow meter at permeate.

[cjf12]

Started at 6:30 with 355 gal of sap. 9:00 now and have 150 gal permeate. Im glad for it but was having better ideas for quicker concentrate.

[Russell Lampron]

Started at 6:30 with 355 gal of sap. 9:00 now and have 150 gal permeate. Im glad for it but was having better ideas for quicker concentrate.

Depending on how sweet your sap was to begin with you should be somewhere around 4% now.

[Bricklayer]

Your membrane is obviously working if it's concentrating sap. And you don't seem to be passing any sugar.
What happens when you run at 200 psi? Do you notice your permeate flow go up or down when you close the needle valve?
1.25 gpm is pretty good for 1 4x40 with no recirc.
With no flowmeter on your RO. To keep your flows up and not foul your membrane I would run it at 200 psi and back into saptank and just keep recircing it until your satisfied with concentration.
Keeping it at 200 psi will let more concentrate through and more flow across your membranes thus keeping them cleaner.
Did you check your membrane when you installed it that the rubber oring on the membrane was facing up and was on the feed side of the membrane? In my housing if I don't have the oring on the membrane ( I forgot to put it on once) what happens is when the membrane is fed with sap it still goes through the membrane making permeate but sap will go around the membrane and out the concentrate side. This just dilutes your concentrate.

[Bricklayer]

Started at 6:30 with 355 gal of sap. 9:00 now and have 150 gal permeate. Im glad for it but was having better ideas for quicker concentrate.

That's 60 gph of water your not boiling off
So if you think about it. If you boil at 60 gph on your evaporator and your running evap and RO at same time your doing 120 gph.
Concentrating all sap then starting evaporator saves a little time but depends on size of RO.
Running say 50 gallons through then starting evaporator and having both run tandem is the time saver. And when your sap is gone. Start recircing from the head tank back into head tank.

[cjf12]

Im pleased that its working at all. I think i was overly excited thinking it would jump up a % on its first pass. Im now at about 3.5 % and 165 gal if concentrate.
Ill check the o ring after im done rinsing. Pretty sure i put it together the way i found it. Who knows if it was right then though.
Thanks for your help as always.
My wife looked at the head tank and asked if it was worth firing the evaporator tomorrow. Guess the ro is doin its job.

[cjf12]

Bumped it back to 200psi.
Running .83gpm.

[Haynes Forest Products]

cjf12 Tell the wife your cooking first thing in the AM you do not want concentrate sitting around spoiling.

[cjf12]

Wish i could. Troubles of having a job. Not enoug time for hobbies. Should be able to have it boiled down at 4 this afternoon. High of 58 today though.

[Waynehere]

Did you check your membrane when you installed it that the rubber oring on the membrane was facing up and was on the feed side of the membrane? In my housing if I don't have the oring on the membrane ( I forgot to put it on once) what happens is when the membrane is fed with sap it still goes through the membrane making permeate but sap will go around the membrane and out the concentrate side. This just dilutes your concentrate.

So I just bought a 250 Deere Run last spring. I removed the membranes for storage and put them back in last week. I had forgotten about the rubber rings and just put them back on, but both in the upright position. This RO runs the filters in series, so I should put the rubber rings on the feed side of the housing, which one is opposite the other? I have not tired any sap yet, but will be tonight. This may have just saved me running sap into my perm tank.

[Bricklayer]

Rubber seal goes on feed side of membrane. The RO will still run and concentrate sap. But not as efficient.

[maple flats]

If your seal is like mine (not an O ring but rather a U shaped seal in a full circle, the open side of the U should face the membrane. Then when there is pressure on the membrane the sides of the seal make a good seal). If it is a true O ring, I have no idea how it might work. It make no difference where the sap flow in, the pressure forces the sides of that U shape tight against both the membrane and the housing thus giving the seal and the ability to force the water thru the membrane.

[maple flats]

My RO has 2 membranes of 4" and when I run at 275 PSI on 37F sap I get about 3x as much permeate as concentrate in my flow meters. At lower pressure you will just get less water removal in each pass. As long as you have no sugar in your permeate, it is working. To verify zero sugar, take a half gallon of permeate, boil it down to 1 pint and test it, that will multiply any sugar x 4 and make it easier to get an accurate reading.

[Bricklayer]

If your seal is like mine (not an O ring but rather a U shaped seal in a full circle, the open side of the U should face the membrane. Then when there is pressure on the membrane the sides of the seal make a good seal). If it is a true O ring, I have no idea how it might work. It make no difference where the sap flow in, the pressure forces the sides of that U shape tight against both the membrane and the housing thus giving the seal and the ability to force the water thru the membrane.

Well explained. I call it an oring by habit.