Adding a membrane to a cdl 250 ro

[markct]

I have a cdl hobby 250 ro, it currently has 2 membranes, both plumbed in series, a high pressure feed pump pressurizes the membranes and then the recirculation pump circulates the sap thru the two membranes. I was considering adding a third membrane to it, in series with the first two, my thought is that the gpm passing the membrane should be the same still so the recirculation pump should be sized big enough, but i believe i would have to add a larger high pressure feed pump as there would now be more permeate leaving thru the membrane so thus the pump wouldnt keep up, am i thinking this thru correctly? seems simple enough but maybe im missing something here so figure i would ask the input of the more experienced folks on here!

[Russell Lampron]

How big is the high pressure pump that is on it now? If it is 3hp it should handle another membrane without a problem. The 3hp high pressure pump on my Lapierre is good for just over 400gph.

[802maple]

It should handle it all right, I have actually expanded a couple CDL 250 by taking the 2 - 4inch membranes off and putting a 8 inch in place of it and as Russ said it took care of just shy of 500 gallons an hour. If you are going to add an additional column and it is going to have a recirculation pump, you will have to do some electrical expansion inside the machine as well.

[Dennis H.]

How does everyone like those small ro's? What can you comfortable run your sap up to on just one pass?

[Russell Lampron]

When I used to hammer mine I could get 8% in a single pass. I recirc now and after a couple of passes I get up closer to 20% which is more fun to boil.

[Mathieu]

Markct talk about the hobby RO, not the Fendeuse model. The 3 membranes hobby exist but it have a bigger supply-pressure pumps and it works on 240 volts.

[markct]

yes its the hobby 250, i see that they have the 3 membrane unit but wasnt sure if it was the same recirculation pump or not, and wasnt sure which way they were plumbed when adding the extra membrane, the high pressure pump is a carbonator type pump so not terribly expensive, i wouldnt mind changing that one out if needed to a larger one as long as the recirculation pump would still work.

[Mathieu]

The recirculation pump stay the same. You only need to change the supply-pressure pump assembly (Motor and pump)

[markct]

Thank you mathieu, it appears that the current pump is 240 gph so adding a 3rd membrane should take me to a 360 gph pump, which is a different style motor etc but not too big of a deal, next i just have to tackle the issue of keeping it 120 so i dont have to change all the controls etc, i may have the feed pump on a relay and powered by its own seperate 120 circuit. thank you for your advice, it seems you are very familuar with cdl products which is great since they lack even a website to look at and compare etc!

[wanting to get into it]

Interesting thread, I am curious about the newer style Lapierre Junior Ro. Can you add a recirculation pump to those without much difficulty? I like the ro, boiling concentrate is by far better than straight sap, but it seems when recirculating the membranes will get fouled up a little. Not a big deal by any means, but I am running anywhere from 900 to 1500 gals of sap through the machine in any given day during the season. What I have been doing is running all of my sap through and adjusting my flow meters to take it to 50/50. This works good and is the fastest way to process the sap, but I am thinking if I can add a recirculation pum I can take 2% to 6% or 8% in one pass. I have the 2 membrane model and plan to try some of the membranes that a few other producers have switched over to in the off season. I really would like to try some of the xle membranes in the machine. And the price of them through Atlantic RO, it is worth a shot to me. But adding a recirculation pump, and the xle's I feel I could really boost the performance of the unit. Just would like some input from the vet's here.

[markct]

wanting to get into it, i just wanted to say that i added a uv light to the concentrate out line on my ro, and yes i know it should be on the inlet but my light is for water and doesnt seal under vac in the housing just under pressure, but what a difference it made, sap didnt leave a bunch of stuff that drops out and settles to the bottom of the tank, and nearly zero tank scum to clean off. But the biggest unexpected effect was that the pressure running sap thru second pass was down almost 50 lbs! i usualy run my sap from my 1650 gal tank into my 400 gal tank then from there up to my 200 gal feed tank so it goes thru the ro twice. the uv light sure made a difference that i hadnt expected, just figured i would try it since i already had it, and sure am glad i did! wish i didnt wait till halfway thru the season to get around to putting it in!

[wanting to get into it]

I will have to give that a try, in no way was I trying to take away from your thread that you started. I thought about that after the fact. I just saw your post and thought I would throw my question out there to see what if any responses I got and maybe someone out there has put a recirculation pump on a Lapierre Junior.

[Mathieu]

Thank you mathieu, it appears that the current pump is 240 gph so adding a 3rd membrane should take me to a 360 gph pump, which is a different style motor etc but not too big of a deal, next i just have to tackle the issue of keeping it 120 so i dont have to change all the controls etc, i may have the feed pump on a relay and powered by its own seperate 120 circuit. thank you for your advice, it seems you are very familuar with cdl products which is great since they lack even a website to look at and compare etc!

The CDL website are suppose to be completly re-designed soon. Just for fun, did you ask your dealer about how much it can cost to upgrade your RO at the St-Lazare shop?

[markct]

i didnt ask my dealer, i bought the machine used after it was a year old, my dealer is realy very unfamiluar with this particular machine, has never even seen one i dont think. My guess tho is that it will be much more money than it is to buy the parts from non maple sources and convert it myself!