The R O bucket

[Jolly Acres Farm]

Has anyone tried this yet, the R.O. Bucket RB-15, http://www.therobucket.com/index.htm?

If so, are you satified, how was performance, is it worth the cost vs. A build yourself R.O.. Would you buy it again?

[ecolbeck]

I bought the rb15 kit which you assemble yourself and is a little less expensive. It has been great for me this season. I concentrate simultaneously to boiling so I dial it in at lower than max capacity so that it keeps up with my evaporator. Even with cold sap I get about 5 gal permeate per hour. I may add the low pressure shutoff next year so that I can concentrate sap overnight or while I’m at work.

[to100]

I have the RM5M I have used it all season about 13 days. Yesterday with cold sap I got 4 1/2 gallons/hour at about 50/50.
Then I preheated sap and then got 7.5g/h total conc and perm. I am in a shed with no heat but have cooktop to preheat and finish near.

[RedMapleCreek]

I bought the RB-15 this season and it has been great. I use it to draw from my outside sap tank and send the concentrate to my head tank that feeds my Mason 2x3 XL. I start the RO an hour or so before I fire the evaporator and then run them simultaneously. Removing half the water with the RO has greatly reduced my boil times and wood use. I would definitely buy it again.

[RedMapleCreek]

Also, I added a pressure gage between the pump and filter, and flow meters with built in needle valves in the permeate and concentrate lines. I removed the small needle valve that came with the RO bucket and instead use the concentrate flow meter needle valve to dial in the balanced flow between permeate and concentrate. The needle valve on the permeate flow meter is left wide open. Flow meters with a suitable range for such low flow are hard to find, I ordered these from amazon:
https://www.amazon.com/uxcell-Thread-0-05-0-5GPM-0-2-2LMP-Flowmeter/dp/B00EZ3T1GM

[antelope76]

I bought the 10gal/hr unit this year and it has been great. Saves time on boiling and firewood used.

[Jolly Acres Farm]

Thank you for all the replies. I appreciate all the information and testimonials on this R.O. that I can get. Im considering the RB15 build it yourself kit. Would like to get 15 gph of concentrate with at least 50% water removal.
What % of concentration are you getting up to, and is this with a single pass or how many passes?

[ecolbeck]

I think it’s rated at 10gph of concentrate at 50%. I don’t measure my sap or my concentrate so I’m not sure about that aspect.

[to100]

They do not recommend more than 1 pass at 50%. It can clog membranes, i tried at first was slow.
You may have to flush more permeate. I had a clogged membrane with no flow of permeate, I had to run several gallons of well water warmed up to free up sugars in membrane, this happened twice and is why I heat sap up and flush.
I think doing this finally got back to normal, Carl was thinking failed membrane.
I am going out now to start up a new run.

[RedMapleCreek]

Would like to get 15 gph of concentrate with at least 50% water removal.
What % of concentration are you getting up to, and is this with a single pass or how many passes?

I doubt you can get 15 gph of concentrate at 50% water removal with the RB-15. Today I was processing 1.4% sap to 8 gph of 2.8% concentrate with my RB-15. The sap was under 40F since it had a skim of ice on it in the tank when I started. It will process sap that is warmer than 40F at a higher rate, but not 15 gph of concentrate. To me, removing 50 percent of the water is a big savings in boil time and does not run the risk of fouling the membranes.

[Greenthumb]

Also, I added a pressure gage between the pump and filter, and flow meters with built in needle valves in the permeate and concentrate lines. I removed the small needle valve that came with the RO bucket and instead use the concentrate flow meter needle valve to dial in the balanced flow between permeate and concentrate. The needle valve on the permeate flow meter is left wide open. Flow meters with a suitable range for such low flow are hard to find, I ordered these from amazon:
https://www.amazon.com/uxcell-Thread-0-05-0-5GPM-0-2-2LMP-Flowmeter/dp/B00EZ3T1GM

Red Creek-

So you used two of these if I am reading your post correct. One telling you flow into the micron filter and one to slow the permeate flow instead of the brass needle valve.

[RedMapleCreek]

Red Creek-

So you used two of these if I am reading your post correct. One telling you flow into the micron filter and one to slow the permeate flow instead of the brass needle valve.

No, the RO always has the controlling needle valve on the concentrate stream, not the permeate stream. I put a pressure gage upstream of the 5 micron filter to see what the typical operating pressure was when the system was running at 50% water removal (it runs between 80 and 90 psi). I put a flow meter on the permeate output line with its needle valve wide open (simply to measure permeate flow). I put the other flow meter on the concentrate output line with its needle valve adjusted to build pressure and force water thru the RO membranes (this needle valve replaced the one that came with the RO Bucket). You can then adjust that needle valve to get a balanced flow between concentrate and permeate, thereby removing 50 percent of the water. This type of flow meter is calibrated for water (specific gravity of 1.0), and the concentrate will have a slightly higher s.g.. Therefor to achieve equal flow the concentrate meter reading needs to be slightly higher than the permeate meter reading since the higher density fluid will lift the indicator weight higher for a given flow.

[Plutoman15]

I got a RO bucket this year as will and like it. I added a second membrane to pull more water out. Still learning but I think I was pulling 5 gallons out in 50 minutes.

[Msboucha]

No, the RO always has the controlling needle valve on the concentrate stream, not the permeate stream. I put a pressure gage upstream of the 5 micron filter to see what the typical operating pressure was when the system was running at 50% water removal (it runs between 80 and 90 psi). I put a flow meter on the permeate output line with its needle valve wide open (simply to measure permeate flow). I put the other flow meter on the concentrate output line with its needle valve adjusted to build pressure and force water thru the RO membranes (this needle valve replaced the one that came with the RO Bucket). You can then adjust that needle valve to get a balanced flow between concentrate and permeate, thereby removing 50 percent of the water. This type of flow meter is calibrated for water (specific gravity of 1.0), and the concentrate will have a slightly higher s.g.. Therefor to achieve equal flow the concentrate meter reading needs to be slightly higher than the permeate meter reading since the higher density fluid will lift the indicator weight higher for a given flow.

Looks like RedMapleCreek and I had the same though process - I too have an RB-15 and added the same flow meters and what a difference in helping you fine tune. The unit works (probably quite well if you have low sugar) but I needed to modify it heavily for our application. Our sugar averages around 3.4 and at times is over 4 -- for most thats what they are seeing after they've already been through their Hobby RO once. I was quickly fouling the membranes due to not enough flow/pressure. There was very little permeate flow and closing down the needle valve to make more restriction did create more permeate initially, but the lower flow quickly fouled the membranes, lowering the concentrate flow to the point it wasn't worth it. I moved the membranes from parallel into series and added an additional 35PSI of head pressure pre-5 Micron filter, and the boost pump after, adding another 70psi (Did it this way because the pre-filter housing is only rated at 70PSI). Pre modifications, I was processing at about 2.3GPH 50/50 (Sugar from 3.4 to 6.8, 1.15GPH permeate /1.15GPH concentrate). Post modifications I am up around 8.5GPH 50/50. Also, previously I tried warming the sap to 50 degrees to try and increase the flow, which did help to an extent (too warm also appears to foul the membranes quicker, partially because warm sap can start generating bacteria), but with the sap now warmed up, boiling post RO was necessary. Post modifications I am running 36 degree sap, which is preferred because I can store the concentrate longer before needing to boil.

[Jolly Acres Farm]

Looks like RedMapleCreek and I had the same though process - I too have an RB-15 and added the same flow meters and what a difference in helping you fine tune. The unit works (probably quite well if you have low sugar) but I needed to modify it heavily for our application. Our sugar averages around 3.4 and at times is over 4 -- for most thats what they are seeing after they've already been through their Hobby RO once. I was quickly fouling the membranes due to not enough flow/pressure. There was very little permeate flow and closing down the needle valve to make more restriction did create more permeate initially, but the lower flow quickly fouled the membranes, lowering the concentrate flow to the point it wasn't worth it. I moved the membranes from parallel into series and added an additional 35PSI of head pressure pre-5 Micron filter, and the boost pump after, adding another 70psi (Did it this way because the pre-filter housing is only rated at 70PSI). Pre modifications, I was processing at about 2.3GPH 50/50 (Sugar from 3.4 to 6.8, 1.15GPH permeate /1.15GPH concentrate). Post modifications I am up around 8.5GPH 50/50. Also, previously I tried warming the sap to 50 degrees to try and increase the flow, which did help to an extent (too warm also appears to foul the membranes quicker, partially because warm sap can start generating bacteria), but with the sap now warmed up, boiling post RO was necessary. Post modifications I am running 36 degree sap, which is preferred because I can store the concentrate longer before needing to boil.
Thank for the reply and modification ideas. I guess what im looking to do is take our 1.85% ( yearly average) to 6-8% in a single pass. That way I could boil as I RO. Maybe I should look into a home biuld instead of thd RO bucket, maybe I need a 4x40 that then the concentrate runs into a 2.5x21 to get to the 6-8% in a single pass.

[Msboucha]

Thank for the reply and modification ideas. I guess what im looking to do is take our 1.85% ( yearly average) to 6-8% in a single pass. That way I could boil as I RO. Maybe I should look into a home biuld instead of thd RO bucket, maybe I need a 4x40 that then the concentrate runs into a 2.5x21 to get to the 6-8% in a single pass.

You could start with the kit, but you would need to modify it in my experience. I can't say for sure, but based on what I am now able to do with my sugar levels, I would say moving the membranes into series (less GPH processed, but higher end sugar), adding an inline recirculation (concentrate is piped back to the pump with a flow restrictor), adding additional pressure ahead of the booster, adding a pressure gauge and some in-line flow meters for better visuals on your flow, you could probably get you close to what you are looking for. I don't doubt some of the flow claims for the bucket, I know others on here are getting good flow "out of the box", but when you start pushing higher sugar levels, more flow/pressure is definitely needed to not only prevent membrane fouling but to make it time efficient. Running off-grid, I couldn't afford to continue processing at a rate of 2.3GPH and leave it overnight like lots of people do, I'd chew through my battery storage, and since it could dip into freezing overnight, I needed to be able to get it back home. If you have the luxury of 110v power, you could get a large pump and really drive the flow, I just needed to stay in 24VDC and this fit the bill.

[anchorhd]

Do you flush the membranes after a run? What do you do between runs, let sap sit in the ro?

[to100]

Go to 1st post on this, there is a link with basic operation

[UB29]

Jolly Acres,
I looked at the RO Bucket deal, but decided to build my own following Hodor's plan. (https://sites.google.com/site/mattat...osmosis-system)
Couldn't be happier with the results. Spent about $350. in various parts....a few hours to put together.....and the outcome is spectacular for my low budget operation.
I routinely run 1.9-2.0% sap through, and in one pass bring it to 8-8-1/2% !! When brand new with the four 150 R.O. filters, I saw 9% on a single pass.
Highly recommend you look at this based on your stated goal above.

[Nickkateclark]

I wanted to let you know that I ordered the RB 15 assembled bucket a couple weeks ago and was pleasantly surprised when I saw that it is plumbed in series and not parallel!

Furthermore, he’s contemplating further improvements for those of us who have a higher sugar content to start with.

I’m getting excited!

[Lanark]

Could someone explain the difference plumbing in series and plumbing in parallel, I'm new to reverse osmosis. I'm building my own reverse osmosis, do all fittings and the membrane housing require teflon tape?

[DRoseum]

Series is passing the concentrate output from one membrane to the next as input. Parallel is splitting the input to 2 (or more) membranes. Remember, each membrane will "double" your sugar content and cut your volumetric flow rate in half (if needle valve is properly restricting permeate output creating appropriate back pressure for 50/50 removal).

That said, in theory I believe you could use proportionally smaller gpd rating membranes for each step in a series set up (e.g. 400 gpd --> 200 gpd--> 100 gpd) yielding the same concentration effects (doubling at each membrane - in this example getting 8 times the concentration on single pass). This would result in pretty low volumes of concentrate, but higher concentration (8 times input for 3 membranes in series).

Parallel set ups can yield higher volumes of lower concentrate by combing multiple outputs. It's a trade off of time vs. Concentration level. Using three membranes you could get 2 times the input concentration levels but more volume of concentrate quicker to start boiling. This will be limited by the max volumetric flow rate of your pump at the membrane working pressure (normally around 100 psi).

A compromise is a 2 stage set up, with some membranes in parallel, feeding into downstream membranes in series. Using 3 membranes you can get 4 times input concentration and still get more volume of concentrate in same amount of time than pure series.

20426

Attached is a picture to help.

Another thread with similar questions/details:
http://mapletrader.com/community/showthread.php?34694-Flowmeter-size-for-homemade-RO.&p=374242#post374242

[Lanark]

Thank you for explaining. I will be assembling three 200 gpd membranes, my booster pump is 200-300 gpd. Hopefully I can assemble correctly to reduce my boiling by 50%.