Homemade RO project

[Gary in NH]

Small Sap RO Project

I’m finally getting around to posting the details of my homemade RO system. I work in water treatment and have worked with RO systems for along time. I started building this RO toward the end of the season last year from different parts from other scrapped systems. I did buy new module housings and RO membranes. This is my 1st full season using the RO system.

System details:

(2) Filmtec TW30 – 2521 RO Membranes rated @ 325 GPD each @ 225 psi
Procon Stainless Steel RO High Pressure Pump
Pressure and Concentrate adjusting valves
Concentrate and Permeate flow meters
On / Off RO Control with low pressure shut-down
Sap Pump – Procon Stainless Steel – will provide 100 psi from gravity feed
10” Sap pre-filter using 1-micron disposable cartridge

This system is located in my basement. I store sap outside in sealed containers and run a ½” line in through a basement window to feed the system. I have a 35 gallon permeate tank and a couple of 5 gallon containers in the basement to collect concentrated sap. When my 35 gallon permeate tank is almost full I redirect permeate to a dry well line. I also have hot and cold running softened water available. Washing the membranes is done by mixing up a solution of RO soap in a bucket and drawing it into the system by way of the sap pump. The system is tubed with food grade polyethylene plastic tubing. The high pressure side uses tubing that is rated for 250 psi. I have utilized push-in type quick connect fittings. This makes moving tubing around for washing or maintenance easy.

The system will process 11 gallons per hour of 34 degree F sap. Production will increase if sap is warmer. I concentrate to 8.0 - 8.5% sugar content. If I start with 65 gallons of sap I will have around 15 gallons of concentrate to boil. I can boil at around 5 to 6 gallons per hour with two propane burners and stainless steel restaurant pans. One pan gets used as a pre-heater.

The system is very small compared to most RO’s. I only have 35 taps and not all are big producers so the system works good for me. The nice thing about this system is I can start it up and walk away for several hours. I also didn’t need to invest in an evaporator. Running the propane burners off a bulk propane tank is a reasonable fuel cost. I am estimating my total syrup production will be around 5 or 6 gallons this year. My kids call the system “ The SAP-erator

[MaplePancakeMan]

That looks awesome. How much did you spend total and if you added another membrane, could you up the output?

[skinny78]

Looks good Gary! Can you explain more about washing the membranes? You mentioned moving tubing around. Have you checked your permeate sugar content? Just wondering if any sugar is getting through your membranes. I hope to build a system similar to yours next year.

[Russell Lampron]

Nice looking RO Gary.

I have seen this question asked in a few threads so here goes. I wash my RO with soap after every use. I then rinse it with all of the filtrate water that I saved from that use. I use the Lapierre RO soap and mix about 2 tablespoons with 15 gallons of water. The ph of the mixture is about 11%. This is the first season that I am checking the ph and can't seem to find what I should be setting it at. If I remember right I was told that it should be in the 10.5 to 12.5 range. My RO has a valve that by-passes the high pressure pump when I am doing a wash cycle and rinse cycle. The soap works best in the 30 to 43 degrees Celcius range and my RO machine automatically shuts at 43 degrees Celcius.

Russ

[Gary R]

Nice looking RO! Thanks for sharing the details. I would think there are lots of small producers that would love something like this instead of investing in a larger rig. Good luck with the sugarin'

[WESTVIRGINIAMAPLER]

What do you RO guys do with really cloudy and low quality sap, won't it plug the membrane fast??

[Amber Gold]

I’m working on a 2x6 this year and plan on expanding to 50 taps next year and further expanding my operation as I find trees around town. To do that I would need to either buy a larger evaporator or buy an RO system. If it wasn’t too expensive I’d rather buy an RO. I was wondering what your full materials list is, where you get those materials, the cost, an assembly diagram and/or instructions. I’ve never seen an RO before, but am mechanically inclined.

I understand that they need to be cleaned after every use, which isn’t bad, but is there any yearly maintenance? Also how often do the membranes need to be replaced and at what cost? Also do they use a lot of electricity?

Thanks for the info.

Josh

[Russell Lampron]

Brandon, I run every drop of sap that I get through my RO, cloudy, buddy or yellowish. It doesn't seem to affect the performeance of the membrane at all. I wash mine more often than the manufacturer recommends because I don't get the sap runs that would require me to run it that long.

Josh, the amount of electricity that my RO uses is much less than the cost of the fuel that I would otherwise burn in my evaporator. I burn wood that I harvest on my own land and the actual dollars spent on fuel for the tractors, chainsaws, wood splitter, wood elevator and dump truck is still a lot more.

Russ

[802maple]

Like Russell said you can't wash them to much. If you wash them religously everyday that you use them, and rinse them before they need it, they will be like the energizer bunny. The R.O."s that we had been running 22 to 24 percent sap thru are now 7 years old and all 6 membranes are still producing over 100 percent of what they are rated to do and not passing sugar. There are sugarmakers in the area that have 12 year old membranes and they are still working well,yet when I used to service them I saw guys destroy them in 2 years as they were just to busy to take care of them, so they pay the price. My theory is when you think you have washed them enough, wash them again.

[saphead]

Jerry,I'm curious as to what brand and model # you're using.Was it Filmtec nf270 that they had the problem with?
Craig