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Melody Bee Farms
02-10-2011, 08:32 AM
Hi I have unit I am looking at purchasing. It is a older Continental unit originally from a hospital. It has 4, 2.5 inch x 40 inch membranes is it worth the effort to try to revamp it to 3, 4x 40 inch membranes,is it even possible I am new to ro so any help/advice is appreciated
Josh

Bucket Head
02-10-2011, 11:33 PM
I'm no expert either, but here's my take. What does it have for pumps? The Leader Evaporator catalog has the pumps, membranes, amperage, etc. listed for their RO's. You should try and compare what they have to what the unit your looking at has. Your already considering swapping vessels an membranes. If the pumps you have won't cut it, you'll have to change them too. Then you'd be building one from the ground up, so to speak. There are a handfull of posts on here from guy's who have built their own small RO's. Take a peek at those. Quite a bit of info and they tell what pumps/components they used. You might want to go that route instead of getting this one and then completely dismantling it and basically starting over. You'll have to figure out what you have, what you might have to get, and what the cost will be to upgrade. It may, or may not be worth it. Good luck with it and keep us posted.

Steve

Dan W
02-11-2011, 05:53 AM
I have done the exact same thing. Continental RO from a hospital. Mine had 3 2.5x40 membranes. Talked with Joe ot Atlantic RO (910-457-9336) about the membranes and I replaced them with one 4x40 xle. It was cheaper to buy the canister and the membrane than 3 2.5 membranes. Seimens bought out Continental but they weren't much help with syrup questions. The pump according to the mfg. will do 250gph. Do you really think you need 3 4' membeanes? This is new to me this year and hope to get to use it sunday or monday-I'll let you know how it works.

green4310
02-11-2011, 10:32 AM
That most have been a fairly high Ps system.
here are some ball park figures for the heck of it.
600psi is the max input Ps allowed
Using 3....XLE 2540 in your original setup, 600psi would get around 45%
One XLE 4x40 @4gpm input or 240gph @600Psi input to get 46%
2 XLE would go around 270psi and get 50%.
The four inchers need a minumum of 2.0gpm on the conc. side to self clean. So using more than 2 membranes with only 4.0gpm input would be a waste.
The nf90 would have been a nice choice also because of less Ps to deal with.
1 nf90...would be around 540psi for 50%
2 nf90........................ 230........ 50%
note: The 2gpm on the conc.side is a minimum spec. You could obviously turn up the Ps to concentrate more, just be aware that you will have to flush out more often.

Green

Melody Bee Farms
02-11-2011, 10:18 PM
All right my current plan is to put 1 8 inch vessel with a maple membrane, I have a 3/4 horse motor and a 1.5 horse motor think this will work?
Josh

Russell Lampron
02-12-2011, 05:50 AM
Josh how many taps do you have and how many gallons of sap do you get in a day? If you have a lot of taps and will be processing a lot of sap don't mess around with this RO and get a maple RO. You will spend thousands on this one when you start talking about an 8" or multiple 4" membranes and the results will be less than satisfactory.

An 8" membrane will be way too big for a high pressure pump that small. A maple RO with a 3hp high pressure pump will do about 400gph with an 8" membrane. That same 3hp pump will do 150gph with a single 4" membrane. If the pressure is there you can cut those numbers in half to get a rough idea of what it will do.

The maple RO's have recirculation pumps to increase the flow through the membrane. I am sure that the hospital RO does not. That will slow it down even more and make it harder to clean.

Melody Bee Farms
02-12-2011, 10:32 AM
The ro from the hospital is a higher pressure unit I am attaching the spec sheet for the ro and the added pump see what you think. I have 2200 taps on buckets so I will usually gather between 2 and 4 thousand gallons a day. actually I cant attach if you have time pm me your email and I can attach to a message
Thanks Josh

Brent
02-12-2011, 10:46 AM
I don't think that is nearly enough HP for the number of taps you've got. I'm guessing that your need a 5 Hp high pressure pump. The recirculation issue mentioned above would concern me a lot. Without the plumping in the system for good recirculation, the membranes will foul up fast and you could be washing for an hour after running for only an hour.

There is a reason maple RO machines are maple RO machines.

Melody Bee Farms
02-12-2011, 10:59 AM
The ro does have recirculation
Josh

Melody Bee Farms
02-12-2011, 11:01 AM
I was planning on using a low pressure filter (recomended by Atlantic RO) does this make a difference?

Melody Bee Farms
02-12-2011, 11:15 AM
the membrane # is xle-440

Brent
02-12-2011, 11:18 AM
Every maple RO has a filter, generally 5 micron, but it will not stop the fouling. That rig may or may not have enough recirculation for sap. It's hard to tell even if you're looking at one. The newest rigs have a 3rd pump on them just for recirculation.

My RO with the one 3 Hp and one 1 Hp pump is rated at 160 GPH. On a 4000 gallon day you would need to run it 25 hours to keep up. And you shoud be shutting down every 4 hours to rinse it and once about every 12 hours to wash it. It's pretty clear you just can't get there from here without a bigger rig than mine. And the hospital rig is 1/2 the power of mine.

I'd say that would be a good rig for someone with about 400-500 taps. I think you need to keep hunting.

In the meantime, do you have enough power in the sugar shack to run the an RO with 7-1/2 to 10 Hp total ????
If gettting that much power is a big expense, talk to Leader about putting a Steam-Away on your evaporator.
I don't know how big your evaporator is but on a 2-1/2 x 8 evaporator the Steam-Away will dump 100 gallons of water an hour and only needs a 1/3Hp motor. They're not cheap, but the operation is 100% uptime while you're boiling and the energy from that litte motor is insignificant.

Brent
02-12-2011, 11:23 AM
The XLE-440 is a membrane. A good state of the art low pressure, high efficiency membrane. I put the a pair of the smaller sisters in mine this year, the XLE-4040. I have not run them yet.

Brent
02-12-2011, 01:21 PM
Since you're looking to unusual sources to try to get an RO there is one more BIG detail you need to keep in mind.

Non-maple systems are normally rated for flow rates with water temperature near room temperature, sometimes even above.

Membranes lose 3% of their flow rate for every degree the temperature drops. So with sap at say 40 degrees or so, you will only get a small fraction of the flow rate. RO's made for maple are rated at typical sap temperatures. In the end you get about 1/3 of the flow rate at sap temps.

Gary in NH
02-22-2011, 11:59 AM
On smaller RO's if you are only running 225 to 250 psi on one membrane you will only get +/-4% concentrate. If you go to two membranes you would get +/-8% concentrate. This is why the Waterguys single RO membrane system needs the sap to be recirculated again to get the concentrate higher. All RO membranes are rated at a 77 degree feed water temperature for standardization of output. This originates from RO desalination applications with warm seawater. At 52 degrees your permeate output will be around 50% of the membrane rating. It will be even less as it gets colder because the sap gets denser and resists flow through the membrane. Temperature has no effect on concentrate because you regulate that with the throttling valve. If you are going to modify an RO system the RO pump size is critical. If it can't build pressure at the desired flow rate the system won't perform properly.