Time to buld a new RO

[harley2003rkc]

I've mostly lurked and learned here but now I'm hoping to pull upon the vast wealth of knowledge here to help build a new RO. We've completely out grown our little starter RO system I built 3 seasons ago and this summer we are planning to build an off grid shack. We're currently averaging 25 gph of evaporation with a divided pan, if I'm diligent stoking the fire and watching the stack temp I can get that number very close to 30 gph. We are planning to switch to a Smoky Lakes hybrid pan in the next two years so with that in mind I'm looking to build something to keep up with a 60-70 gph feed rate, or come as close as possible. I've been losing sleep reading threads here and have put together what I'm hoping is a decent plan to assemble a 2 x 4040 membrane system. So with that said, would someone with some real knowledge on the subject be so kind as to critique this and maybe throw some wisdom my way?
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[BnSmaple]

Looks good only thing I would do is move the pre filter on other side of of pressure gauge/cutoff/recirculating line…also make sure both pumps are wired to low pressure cutoff…only other advice would be your RO needle valve unless you buy a expensive full port one you will not get enough flow wide open to avoid pressure spikes on startup and wash. I would recommend either a gate valve there or keep that in place place and plumb in another additional valve you could call that your wash valve….then just leave that open on startup and during wash cycle..

[harley2003rkc]

Like this?
Also, what are others using for pumps? I think the high pressure pump is the right answer but I'm still looking into which pump is best for the low pressure pump.
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[BnSmaple]

That looks good…..the last RO I built I used a stainless sprinkler pump from harbor freight it worked great and fairly cheap

[harley2003rkc]

I keep reading about others using similar setups with pressures as low as 150psi with one brand of membranes and up to 275 psi with another brand of membranes. What are the pros and cons of both?

[darkmachine]

I built a 2 membrane 4040 RO 2 years ago, I used a 1hp motor paired with a 330 gph procon pump. for a feed pump I used a pressure pump from a small cabin. it had like a 2 gallon pressure tank on it, I just removed the tank. Works great, I installed a needle valve for re-circulation I run at 250 psi, and can make 8 percent if i push it, it's slow. I normally take it to 4.5-5.5. I am rebuilding this season and adding a multistage jet pump and taking out the re-circulation valve/loop to help preserve membrane life.

[harley2003rkc]

darkmachine which membranes are you using? How many gallons per hour of RO'd sap are you averaging?

[MarquisVII]

All,

I want to do something similar and only know what I've learned so far from the forum and perusing the RO Bucket website, which is very helpful.

harley, - how many taps/species/vac lines?

My signature is up to date, so it will be overkill next year to add a single 4040 but I need more sleep and I don't have a shack so it can be a hassle working around weather. I wouldn't have survived this year without my 3x150, but it left me with MUCH to be desired. I want to plan for high flow days where I might get 250gal into my 275gal tank. Since this setup is overkill, I'm thinking it would allow me to RO the concentrate into the 275gal for an hour or three while continuing to collet sap in it, then switch the concentrate line to my 55gal head tank as I prep to fire up.

The brainstorming started yesterday when I realized I have a 1.5hp motor sitting idle on a really old and unused wood lathe. I would need to either change the shaft (which I don't know much about) or find the right Procon to fit what I have, and there's about 100 different models on their website that all look basically the same so I thought I might call sales to learn more. In any event, I see you guys use the 330gph pump, while Carl at RO Bucket uses a 3/4hp motor and 190gph pump even on his 2x4040 unit. Did you choose 330gph for future expansion? At what flow rate is a low pressure pump needed?

[darkmachine]

darkmachine which membranes are you using? How many gallons per hour of RO'd sap are you averaging?

I got the membranes off of amazon they are Max Water XLP-4040 2300gpd @ 100psi. My records aren't the best, but this season I would bring in 200 gallon of raw sap at 1.5%, fire up the RO to get a head start and then start my fire on my 2x6, in less than 3 hours i could have it all boiled and the RO flushed, and back to make my evening run in the school bus. all my tanks were empty every day, it was nice, i could do other things, lol. We estimated we had an effective sap processing rate of between 80 and 100 gallons an hour between the RO and the evaporator.

[Maples Maple]

This looks like a nice build. I have a similar set up with procon 330 gph. I usually run at ~235-240 psi with fairly high recirc (no flow meter on it) and get 8-9 brix out. My flow rates are 1.5-2 gpm perm / 0.5 gpm conc. Depending on temp, etc. If you are boiling at 60 gph then you can start the RO first for a while or drop the brix out to get it up to 1 gpm.
If you are looking for 5-6 brix then the 190 might be fine but 60-70 gph of conc out is a lot for that size pump.
Good luck and let us know how it comes out and what you decide to do.

[harley2003rkc]

Maples Maple what size motor are you running on the Procon 330. I've read about guys running everything from 1 - 2hp. I'm seeing 1.22hp required at 250psi (factory spec) but that doesn't take into account the supply pump pushing into it, which is where I'm not sure how to look at the pump curve. From what I've found so far I'm highly inclined to say there's no reason for a motor larger than 1hp.

MarquisVII we have somewhere around 250 taps out right now on gravity, all sugar maples. I'll get a count when we pull them this weekend.

[Maples Maple]

I am using a marathon 1 3/4 hp pump on the procon 330. I have 1 hp supply pump that has a zero head flow rate 800 gph. Following the supply pump curve, at 140 gph it is supplying ~45 psi. I have my filter between the supply pump and HP pump. I do not have a delta P reading on my filter so I am not sure how much I am actually feeding into the HP pump. I am running 2x 4040 XLE in series which similar to your plan.

I did look this up a couple of years ago and thought the braking force was going to running very close at 1hp. I had a 3/4 hp pump which was not going to cut it. It is better to have margin. That said mine is on a dolly and getting it out in the mud / snow from the house to the sap tank is no fun. Heavy!

[Rselleck91]

When building a ro, use nitto espa4 membranes. Those are the ones that guys call “maple specific”

When moving forward from a procon pump a goulds 10gbs20 is your part number for a stainless multistage pump suitable for a true food grade hp pump.