CDL Nano RO

[thedeer2]

Anyone else see the new Nano Ro in the 2021 CDL catalog. I’ve never used RO and I am super unfamiliar.
I am confused by the specifications, and I am trying to figure out how many gallons of raw sap it the 3 membrane unit will process.
The specs list Water Removal at 10-13gph @5-6 brix. Is this spec the amount of concentrate per hour produced? Or amount of raw sap processed?

For those familiar with RO, does this new CDL unit seem promising for $700 bucks or is the RO Bucket a better investment?
https://www.cdlusa.com/wp-content/up...-RO_manual.pdf

[DrTimPerkins]

From the manual, it appears that the 3-membrane unit will produce 10-13 gph permeate @ 5-6 brix at a ratio of 65 (water): 35 (concentrate) -- assuming 2 Brix incoming sap at 42 deg F at 100 psi.

So if it is producing 10-13 gph permeate, the 3-membrane unit would generate 3.5-4.5 gal concentrate per hour (10-13 gph x .35) given a 65:35 reduction).

The 2 membrane unit would produce 3-4 gal of 4-5 Brix concentrate per hour and 6-8 gph of permeate (50:50 reduction) at 70 psi at 42 deg F.

RO buckets do a 50:50 reduction (permeate:concentrate) at 40 deg F at a 8, 12, or 20 gph sap processing rate, so producing 4, 6, or 10 gph of both permeate and concentrate depending upon the model.

[ecolbeck]

I have to respectfully disagree slightly with the numbers for the CDL unit reported by Dr. Tim (sorry).

With a 65:35 ratio of permeate to concentrate, an output of 10 - 13 gph of permeate would yield an output of 5.4 - 7 gph of concentrate.


65/35 = 10/x

350 = 65x

x = 5.4


When comparing the products the larger CDL version seems to have the advantage of a recirculation pump and both versions have a built in pressure gauge as well as frames. However by comparison, the ROBuckets seem to process greater amounts of sap for their cost albeit at a lower concentration.

[steve J]

I am trying to learn about these 2 RO's? And I have zero knowledge of RO in general. It appears the cdl unit removes 15% more water but at a max output of 7 gpr? So it would take longer to fill my 30 gallon head tank but since sugar content may higher It would produce syrup faster?

[ecolbeck]

The larger CDL unit will produce a stronger concentrate than the ROBucket units. However, that really only matters if you’re willing to pay a high price for it and accept it’s slow rate of production.

[maple flats]

I have to respectfully disagree slightly with the numbers for the CDL unit reported by Dr. Tim (sorry).

With a 65:35 ratio of permeate to concentrate, an output of 10 - 13 gph of permeate would yield an output of 5.4 - 7 gph of concentrate.


65/35 = 10/x

350 = 65x

x = 5.4


When comparing the products the larger CDL version seems to have the advantage of a recirculation pump and both versions have a built in pressure gauge as well as frames. However by comparison, the ROBuckets seem to process greater amounts of sap for their cost albeit at a lower concentration.

I think you have it backwards. the 65% is permeate, the 35% is concentrate, anyone can correct me if I'm wrong. It is saying 10-13 gph water removal

[carls47807]

The RO Buckets with 3 or more membranes can easily concentrate to 6% in a single pass by running the concentrate 35% and 65% permeate. Flow rates would be the same as the cdl nano when doing that (using the standard correction factors for sugar percentage).

The recommendation on these smaller units has always been to run them at 50/50 because it was difficult to know what they were capable of when the instructions were written, and a lot of smaller folks don't test or know their input sap concentration. You wouldn't want to run past 50/50 when you are starting with 3 or 4% (which isn't uncommon).

[thedeer2]

I have to respectfully disagree slightly with the numbers for the CDL unit reported by Dr. Tim (sorry).

With a 65:35 ratio of permeate to concentrate, an output of 10 - 13 gph of permeate would yield an output of 5.4 - 7 gph of concentrate.


65/35 = 10/x

350 = 65x

x = 5.4


When comparing the products the larger CDL version seems to have the advantage of a recirculation pump and both versions have a built in pressure gauge as well as frames. However by comparison, the ROBuckets seem to process greater amounts of sap for their cost albeit at a lower concentration.

Thanks for all the help. So to summarize and clarify. Assuming Sap begins at 2 Brix...

At maximum capacity the 3 membrane Nano ($709) can process 20gph of sap outputting 13gph of permeate and 7gph of concentrate @ 6Brix. This is a 4 brix increase per Pass through the system. Do I have that correct?

A comparable RO bucket would be the RB 15 ($525), which can process 20gph of sap into 10gph of concentrate @ 4brix. This is a 2 brix increase per pass through the system.
To get an equal 6brix output would require a second pass through the RO bucket. So to recirculate and get an equivalent output of 6 brix the RO bucket is really processing sap at 10gph. Correct?

Looking at the materials used in their construction, I would assume the Nano is superior due to it using 600gpd membranes vs RO Bucket's 400gpd, and the Nano having the added recirculation pump. But, is this worth the additional cost...?

[mainebackswoodssyrup]

Read Carl's post above. He's the RO bucket guy. Looks like they are identical in capability but you should know what sugar content before you start up.
Look at the RB25 kit as well. It's not the bucket setup but can do more GPH than either. It likely comes down to what you want.........gph, % sap, cost, nearby parts convenience, etc.

[carls47807]

Thanks for all the help. So to summarize and clarify. Assuming Sap begins at 2 Brix...

At maximum capacity the 3 membrane Nano ($709) can process 20gph of sap outputting 13gph of permeate and 7gph of concentrate @ 6Brix. This is a 4 brix increase per Pass through the system. Do I have that correct?

A comparable RO bucket would be the RB 15 ($525), which can process 20gph of sap into 10gph of concentrate @ 4brix. This is a 2 brix increase per pass through the system.
To get an equal 6brix output would require a second pass through the RO bucket. So to recirculate and get an equivalent output of 6 brix the RO bucket is really processing sap at 10gph. Correct?

Looking at the materials used in their construction, I would assume the Nano is superior due to it using 600gpd membranes vs RO Bucket's 400gpd, and the Nano having the added recirculation pump. But, is this worth the additional cost...?

Although I am slightly biased.

The RO Bucket can get to a higher sugar percentage overall because it runs at 150psi (vs. the nano running at a max of 70-100psi). As sugar concentration goes up, osmotic pressure also goes up, making it more difficult to separate the water out. The 3 membrane thru 5 membrane RO Bucket systems can run a single pass up to 6%. For single and 2 membrane systems it's best to run a 50/50 pass.