Homebuilt RO with 400gpd membranes

[DaveB]

I decided to bite the bullet and build myself an RO system (http://www.therobucket.com/RB15kit.pdf) because of the tsunami of sap I'm getting. I've ordered a bunch of parts based on the homebuilt systems that others have built but I think I ordered a couple of mis-matched components. I saw that people were using 400gpd membranes so that's what I ordered (https://www.amazon.com/Membrane-Solutions-Astra-Clear-400GPD-3012-Residential/dp/B071SGLF18/) and I also ordered housings (https://www.amazon.com/Membrane-Housing-Connections-Reverse-Osmosis/dp/B00IR4ZN62/) that I thought went with the membranes but that was not the case. So, now I have these 400gpd membranes that are 3" wide and 2.5" membrane housings. I can order a 3" housing for the membrane but I'm wondering if there is a 2.5" 400gpd membership. My question is, what are people using for 400gpd membranes and housings? Should I get the proper housing or a different membrane?

[Bmeehan19]

I literally just did the sane thing you have but all my parts arent in yet. I went with the 3012 ro membranes and housings. My reasoning was I basically mimicked therobucket and those are what he uses as I have zero experience with RO. Hope that kinda helps.

[DaveB]

I literally just did the sane thing you have but all my parts arent in yet. I went with the 3012 ro membranes and housings. My reasoning was I basically mimicked therobucket and those are what he uses as I have zero experience with RO. Hope that kinda helps.

Yeah, that's basically what I'm doing. I'm torn between ordering the right housings or a different sent of membranes. The worst part is that I have more sap than I've ever had in a week and I specifically ordered everything on Monday to be delivered today so I could put it all together and use it this weekend but I don't think that's going to happen. Where did you order them if you don't mind me asking? eBay? That's the only place I've seen them.

[metalhead62]

just a curiosity ? you use a 400 gpd membrane does it matter which one i mean i gathered parts for a 4x40 and i use the xle but is there a special 400 gpd membrane you guys use

[DaveB]

just a curiosity ? you use a 400 gpd membrane does it matter which one i mean i gathered parts for a 4x40 and i use the xle but is there a special 400 gpd membrane you guys use

It might be a cost perspective. The three membranes I purchased along with their housings are under $200 whereas I think a single 4x40 is that much along without the housing. I was also under the impression that you needed a larger booster pump like a Procon with the 4x40's. I purchased an aquatec.

This is the membrane I ordered:

https://www.amazon.com/Membrane-Solutions-Astra-Clear-400GPD-3012-Residential/dp/B071SGLF18/

Here's the housing:

https://www.ebay.com/itm/NSF-Reverse-Osmosis-Membrane-RO-System-Housing-3012-400-GPD-Water-Purifier/253210943093

[metalhead62]

dave i was just curios if it was a specialty ro cartridge like the xle or if any one would work based on gpd

[carls47807]

The 3012 is the "cartridge" size. The housing will fit multiple membranes between 200 and 400gpd (with the 3012 designation). The 3013's are a little taller and skinnier. I've seen 600gpd membranes in the 3013 size. I use the 3012's in my ro buckets because the 3013's are too tall.

The xle membranes can work up to 600psi. These household ones are 200psi max (most household booster pumps deadhead at 130psi anyways).

Carl

[metalhead62]

i was more wondering if they all work to catch sugar like some 4x40's will pass some sugar at any psi some wont some are better than others because they work quicker at lower pressures so i guess the answer is except for size and gpd rating they are all the same

[carls47807]

Got ya the xle is rated for 99% rejection rate. Most 3012's are 96-98%. The Dow are rated the highest. I do know that it's not uncommon to see up to .02 % sugar in the permeate with the 3012's when sap is in the 30's.

[Bmeehan19]

Yeah, that's basically what I'm doing. I'm torn between ordering the right housings or a different sent of membranes. The worst part is that I have more sap than I've ever had in a week and I specifically ordered everything on Monday to be delivered today so I could put it all together and use it this weekend but I don't think that's going to happen. Where did you order them if you don't mind me asking? eBay? That's the only place I've seen them.

I ordered from Amazon. Was here in a day and a half.

[metalhead62]

daveb sorry for hyjacking your thread

[DaveB]

I ordered from Amazon. Was here in a day and a half.

Hmmm...I only see the membrane on Amazon, not the housing. I looked and looked before winding up ordering the correct housing from a seller on eBay. Oh well. They should be here on Tuesday which will give me time to put things together for next weekend.


daveb sorry for hyjacking your thread

No worries! It's educational.

[Bmeehan19]

So I ran my setup today with the 400gpd in 3012 in paralell. 1st pass on 2% was coming out at a little over 5%. Processed at 120psi and did 20 gallons in less than 2 hrs. Ran it a second time at 130 psi and it came out @ 8%. This machine is awesome!!

As a side note, the aquatec pump I got can go up to 160. My limiting factor is my sediment prefilter that says max psi is 125. Not sure how far I should push it past 130. Although I may not get enough flow over the membranes at that psi.

[maple flats]

The sediment filter should be before the pressure pump, not after it. Do you have access to another pump to feed the RO? If yes, use that at a lower pressure thru the sediment filter then run the membrane at 150-160 PSI, you will remove more water on each pass. If you do try the higher pressure, you want a high pressure shut off or keep a real close eye on the pressure so you don't blow the housing for the membrane. Likely the housing is the weak link, mot the membrane itself.

[maple flats]

If you don't have another lower pressure pump, can you set the RO up to gravity feed thru the sediment filter and to the high pressure pump then it can pump up for the membrane?

[Bmeehan19]

The sediment filter should be before the pressure pump, not after it. Do you have access to another pump to feed the RO? If yes, use that at a lower pressure thru the sediment filter then run the membrane at 150-160 PSI, you will remove more water on each pass. If you do try the higher pressure, you want a high pressure shut off or keep a real close eye on the pressure so you don't blow the housing for the membrane. Likely the housing is the weak link, mot the membrane itself.

That makes sense. Could my pump pull through it? I dont have another pump right now. Also I noticed in my batch today that there is some whitish sediment/gunk in the bottom and the syrup is cloudy. Not typical niter or sand. Did I not rinse the membranes enough? I put about 15 gallons of distilled through it. I read that somewhere, cant find it now, that that was enough on a new membrane.

[Mark B]

Sorry to jump in here, but any ideas on getting the 3012 housings to seal better. I have 3 housings and all 3 weep water. Are there better o rings or do I need to tighten them more?

[DaveB]

So the housings finally arrived and they required a few different fittings but thankfully I was able to find everything I needed after a few trips to Home Depot. I also purchased a pressure gauge so I could monitor things. I mounted everything to a couple of 2x4 peg boards and I plan on mounting that to a dolly from Harbor Freight.

My understanding is that after I put the filter and membranes in and run I need to run some straight water through everything for about 30 minutes with the valve wide open. After that, I can try running some sap through it and close the valve to create pressure and that should create concentrate and permeate. Is that correct?

And then at the end of the day I should run water through the membranes with the valve wide open. Is that the correct procedure?

17898

[metalhead62]

daveb yes you want to rinse the membranes do not use city water as the chlorine will hurt the membranes differing opinions on well water some say once a year is no biggy some say use distilled water. city water if you can let it sit out for 3/4 days will kill the chlorine. not sure but i would think for rinse you would want to put back pressure 50/50 to try to force water through the membranes after first rinse keep permeate to wash with after that maybe some with more experience and better typer then i will chime in

[Greenthumb]

where do you guys find the pressure gage. I’ve had the homemade ro for about 3 seasons now and can’t seem to find a gage that last. I’ve bought them from Home Depot and Lowe’s. Right now I’m running without one and using my hydro cup to take samples so often. Seems to be working
And I just keep adjusting the needle valve

[DaveB]

where do you guys find the pressure gage. I’ve had the homemade ro for about 3 seasons now and can’t seem to find a gage that last. I’ve bought them from Home Depot and Lowe’s. Right now I’m running without one and using my hydro cup to take samples so often. Seems to be working
And I just keep adjusting the needle valve

This is the one that I ordered but I can't speak personally to it's quality because I have not used mine yet (I'm still waiting on a replacement transformer):

https://www.amazon.com/gp/product/B0124FAV6Q/

It seems to have good reviews and be a solid product but we'll see.

[DaveB]

I used my setup the past weekend for the first time and I wanted to share my experience if it would be helpful to others. The unit basically operated as expected and I'm happy about having a supply of fresh water that I've found several uses for. That alone in sugarhouse without running water is great!

I do see some leaks in the seals on the filter housing and membranes despite wrapping them with teflon tape. I think I need a wider tape and will be getting some this week to see if that takes care of the problem.

The system is running about 110psi. I don't know if that is normal or not but it seems to run there steadily.

I initially rinsed the membranes before use and then when I closed the valve on the concentrate end made sure that the water coming out the other end was clean and that the sap was concentrated. I passed 1.5% sap throught it the first day and it took it to 3%. The second day I ran 2% sap and got 4% out. The rate at which the concentrate comes out is about 7.5 gallons an hour. On the other end I'm getting about 25 gallons of water each day which is about one hour of boiling for me. That's the big savings to me. It's like having a side evaporator taking off water for me!

I did want to ask about the needle valve that others are using. I wound up buying a dial/gate valve and it works but I'm thinking a needle valve might work better. Can someone share what they are using?

[hodorskib]

I had similar problems with leaks and was able to fix them by using a thick teflon tape - https://www.amazon.com/Oatey-15100-Hercules-Thread-Sealant/dp/B00DZV3L5C ( I had to use 8-10 wraps) and then had to use a silicone lubricant on the o-ring in order to tighten enough to get a better seal. My 3 x 400gpd system is also running around 115-125psi. I have found that in order to provide enough flow through the larger membranes it is better to back off on the needle valve and recirculate rather than try and do in one pass.

[jdircksen]

What pump are you using with the 400gpd membranes? I have an Aquatec 8852 right now using 150gpd membranes but would like to get faster processing rates by switching to 2 of the 400gpd membranes.

EDIT - disregard. found the answer in this thread http://mapletrader.com/community/showthread.php?33793-The-basics-of-building-a-small-RO

[barnbc76]

I have an aquatech 8800 it seems adequate for the task with 2-400gpd membranes. I dont really know the rate I'm getting as the first batch last week was already close to 3.5% and now I'm doing 2.5% and recirculating back into the same tank. In 5 hrs it removed about 17-18 gal of water.

[rlapointe]

This is the one that I ordered but I can't speak personally to it's quality because I have not used mine yet (I'm still waiting on a replacement transformer):

https://www.amazon.com/gp/product/B0124FAV6Q/

It seems to have good reviews and be a solid product but we'll see.

I got the same one from same place. Works fine.

[rlapointe]

Hmmm...I only see the membrane on Amazon, not the housing. I looked and looked before winding up ordering the correct housing from a seller on eBay. Oh well. They should be here on Tuesday which will give me time to put things together for next weekend.



No worries! It's educational.

I bought both together on Amazon.ca (.com should have the same)
https://www.amazon.ca/gp/product/B071FJT7J9/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1

(https://www.amazon.ca/gp/product/B071FJT7J9/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1)