Building RO. Let me know if I'm missing something.

[AJ Peacock]

All,

I've spent a LOT of hours studying the posts on this site. I think the light has finally dawned w/re to what is needed to make an RO for Syrup production.
I'm thinking about an RO that is similar to the one Teuchtar so excellently explained/documented back in 2008.

Some background. A few friends and I have all been doing a little syrup individually for the last few years (5-10 gallons each). We just got access to 160 acres of maples and decided to take a run at upping our production a bit! My part of the project is the RO.

Design constraints:
1) 75% water reduction.
2) 100 gallons sap input per hour.
3) 12 hour/day duty cycle.
4) 1 or 2 pass is OK.

Overall design.
2 x 4" x 40" membranes run in parallel. (XLE-4040)
1hp motor.
Procon 330GPH bolt-on pump. (will run at 200psi / 320gph with a 1hp motor)
4.9gpm 50psi constant pressure delivery pump to feed the Procon (will probably feed at 4.5gpm pushing sap through 1 micron filter)


I'm thinking that the 50psi input feed + the Procon should give me somewhere around 225-250psi at around 250gph through the membranes.
If I process the sap twice, I'm hoping I can reduce the water 50% each time, for a 4x concentration of the sap for a 125gph overall throughput.
By rinsing for 15 minutes every 4 hours (100 gallons or so) and then washing after 12 hours, I should be able to get an average throughput of
120gph over a 12 hour span. I'd be able to handle around 1400 gallons and reduce it to 350 gallons of concentrated sap.

As you can see, I don't have a recirculation pump in this design.

I'd appreciate your opinions on a pump that would fit in this design. The membranes have a maximum flow rate of 14gpm, so I suppose a a recirc in the range of 12gpm would be appropriate???

One more thought. If I ran the same parts, but put the membranes in Series (switched them every 4 hours after rinsing), could I hit the 75% water reduction and 100gph rate in a single pass?

Thanks in advance for any and all comments,
AJ

[maple flats]

My RO by Ray Gingerich has no recirculation pump. It has 2 4"x40" membranes. It goes thru a feed pump (Northern Hydraulics belt drive 1" pump) and leading into this pump is a 2.5" x 20" prefilter in 10 micron. Then the sap is run into a pressure washer pump, also belt drive. The flow thru the membranes is restricted at the outlet and adjustable. I run at 275-280 PSI when I am at the sugarhouse, when I leave to let it run on it's own I turn it back to 250 PSI. At the 275 setting it removes 75% of the water in one pass, at 250 that drops to about 60%. My unit has a high and low pressure shutoff. High is set at 300 PSI and low is down to maybe 5-10 PSI. The low shuts the RO off when I run out of sap and the high protects against over pressure failure. Mine was on a 4HP Honda engine the first 2 years, but I got everything needed to convert to electric for next season. Ray told me to buy a 2 HP 1725 motor and I bought the rest from Ray to convert.
I started with gas because I had to generate my power, I now have grid power, and 6.32 KW solar, net metered so I want the electric to run quieter and to use some of my net metered energy credit. I now have over 1400 KWH in my favor on the meter. That will not be used up in even a fantastic season running the electric powered RO.
My RO does 240-260 GPH depending on the sap temperature. It takes 2% sap up to 8% in one pass. I also recirculate concentrate taking it from 8% up to 12-14% by drawing from and returning to the concentrate tank.

[bowhunter]

AJ,

Here's a link to Dow's RO design site. http://www.dowwaterandprocess.com/support_training/literature_manuals/lm_techinfo/designstps_balance.htmThere's a lot of good information there. In addition to maximum flow through to the membrane, the manufacturers also try to limit the minimum concentrate flow. For a 4 inch membrane the minimum recommended is 3-5 GPM depending on the service. You may not get very good performance over time without recirculation because your concentrate flows will be down to about 50% of the minimum recommended per membrane at 50% reduction per pass. I know there are a lot of people on this site who build RO's with lower flows than recommended and they seem to work pretty well, but not sure how long the membranes will last. Also the temperature has a big affect on permeate flow at a given pressure. Membrane permeate rates are all tested and published on water at 77 degrees F. Your sap will probably average less than 40 degrees and so you lose about 50% of the flow.

[lew]

I'll leave the actual build of the RO to others. My concern is the 160 acres of maple. Even if you are only at 50 taps per acre, that's 8,000 taps. Your RO will be way to slow. On a run of only .5 gpt that's 4,000 gallons. Including rinse time it will take you 2 entire days to finish the syrup from that one litlle run.

[AJ Peacock]

Thank you all for your input/information.

Thanks for the info about belt driven pumps. There is such a large number of different types (and costs) of pumps, it boggles the mind.

The DOW site is helpful, are there any 'standard' numbers used when converting the 'water' RO numbers to sap handling numbers?

As far as the 160 Acres of Maples. It's not 100% maples and we don't plan on even scratching the surface of that property.
We plan on picking/choosing the easiest access trees and staying between 500-1000 taps, that's why I said the RO needed to be in the 100gph range.

Since we are essentially starting from zero, we want to have modest goals and see how it goes the first year. Even though the property would be perfect for a gravity setup, we are going to stick with buckets and very short tubing runs to collection points, since we can't do any 'permanent' gravity runs. We'll haul the sap back to the processing point. We have access to grid power, but will have a generator backup just in case. Since the property is quite a ways north of us (3-4 hours), we will need to be 'portable/flexible' with our plans. Typically, the sap run up north is 2-3 weeks later than down here where we live, so we plan to use the RO to process a few smaller batches at the beginning of the season down here, then relocate our stuff up north. We will have the trees ready to be tapped up north. We all have pretty flexible schedules, so once the run starts up north, we can take a week or 2 to 'play' with the sap.

Regarding the RO, we want to use parts that can be re-purposed if we decide we need more throughput. We can move from 2 to 4 membranes by upgrading the initial pump (or running a second pump in parallel). We will be building the mechanical and electrical portions of the RO to support a 4 membrane system.

Only time will tell. Until we actually order some parts, it's just an interesting research project.

Thanks again for your input and such a great site,
AJ

[bowhunter]

You will probably get about 50% of the permeate flow on cold sap vs. water at standard conditions, but it depends on many variables: temperature, average sugar content, degree of fouling, pressure, etc.

[maple flats]

Even at 1000 taps you need a much larger/faster RO. On a fairly good day with vacuum you should expect 2 gal/tap, 1 gal/tap on a so so day That is 1000-2000 gal. You still could not even keep up with the sap unless you buy a much larger evaporator than would be needed with the proper RO.
With just 1250 taps my RO runs up to 6-10 hrs on a good day and that is going thru between 2000 and one day I had 2800 gal to process and my RO processes 240-300 gph depending on sugar % and sap temperature. I will soon be going to a 500 GPH unit, but not until 2015 season as I continue to add more taps.

[AJ Peacock]

As I said, 500-1000 taps (all bucket). So lets say 750 taps on bucket. A good day would still be lower than 1000 gallons. 100gph RO should handle that.

Knowing the trees there and the amount of canopy they have (not a lot), I'll be ecstatic if we get 1 gal / tap / day. If we're getting too much sap for our setup, then we'll have learned to not put in so many taps :-)

Thanks,
AJ



Even at 1000 taps you need a much larger/faster RO. On a fairly good day with vacuum you should expect 2 gal/tap, 1 gal/tap on a so so day That is 1000-2000 gal. You still could not even keep up with the sap unless you buy a much larger evaporator than would be needed with the proper RO.
With just 1250 taps my RO runs up to 6-10 hrs on a good day and that is going thru between 2000 and one day I had 2800 gal to process and my RO processes 240-300 gph depending on sugar % and sap temperature. I will soon be going to a 500 GPH unit, but not until 2015 season as I continue to add more taps.

[maple flats]

When I used buckets, the average sap/day was over 1 gal on most days that had decent flow. We did have a few buckets that were over flowing most days on 4 gal buckets but that just helped the average yield. If you have 750 buckets I'd guess you will often get 1000-1200 gal/day. I think you could sell any excess sap if you can't keep up. Many producers with an RO buy sap too, as I do. With a 100 GPH RO you would not find it feasible to buy, my 250 is almost too small to do it.

[AJ Peacock]

You will probably get about 50% of the permeate flow on cold sap vs. water at standard conditions, but it depends on many variables: temperature, average sugar content, degree of fouling, pressure, etc.

What about gallons per hour? I've read that flow over the membrane should be kept less than 13gpm for the xle-4040. That equates to over 700gph. I understand that the recirc pumps are used to keep the flow up across the membranes to keep them from 'clogging'. Can a larger main pump be used (like 600gph) for a single 4"? making the need for a recirculation pump unnecessary? It would seem that the higher the gph, the higher the pressure should be to keep the membrane working efficiently. is there any rule of thumb regarding the pressure vs. gph? A chart or rule of thumb that answered that question for me would really really help.


Can anyone share the actual part# for a recirculation pump that allows at least 300psi case pressure, flows around 15-20gpm and stays under 30 psi?

Thanks,
AJ

[bowhunter]

AJ,

You probably would be better off to call somebody like Ray Gingerich. With the size of equipment needed you're going to have more invested in equipment than it would cost to buy one of Ray's units. Maple Flats has one of his units and he has the contract information. I built a much smaller version which I could do economically, but if you're in the 100 to 250 GPH range it's going to be more difficult to beat Ray's price.

To answer your questions, there are no easy rules of thumb that will work for every case. You can use one pump to handle both pressure and recirculation. It's a little less efficient based on power consumption, but one pump will definitely work. The membrane manufacturers tend to keep the data on permeate flow vs. pressure out of sight because they have patents on their particular technology. Not sure about your pump question and the 30 PSI. Is that maximum suction or inlet pressure?

[TunbridgeDave]

AJ, I wanted to chime in because what you are building is basically what I have in my Small Bros R/O from the late 80's. It has the same procon pump and a similar feed pump. I am also running two xle 4040s now. I can get a permeability test at 55 degrees and 200 psi of 210gpm when the system is clean. I have great luck running it at lower pressures around 200 at the beginning of the day and up to 300psi when things get dirty. Mine is set up in series and the best I can do is about 50 to 60% in one pass because it has no recirc pump. But it does have a recirc valve. This essentially accomplishes the same thing as having another pump. It's a double valve setup actually, with a ball valve(which is closed for cleaning), and a parker(needle) valve for fine tuning the flow. When concentrating it lets the concentrate output return to the inlet of the procon pump giving you the recirculation. You adjust this needle valve and the main concentrate output valve to get the desired pressure and concentrate level by reading the flow meters. Using this method, I can easily get the 75% water removal I want in one pass and it keeps the flow up through the membranes. The overall flow rates of both concentrate and permeate are lower using this method, so having an additional recirc pump would improve the flow I assume, but it works. The other method which works well for me is to send the concentrate back to the holding tank and recirculate it that way until the concentrate output has increased to the desired percentage. Then you just divert the concentrate to the feed tank for your arch. I can make more permeate per hour this way which is how you should look at it. The second method has to be monitored more because as the sap gets more and more concentrated the pressure goes up and up. I have no high pressure shutoff, only a low pressure cutoff switch for when I run out of sap. I also had to set up a wash tank and I'm changing my 10"pre-filter to a 20" one. (5 micron filters are plenty) Hope this was a help to you and best of luck!

[AJ Peacock]

Thanks for the input. With regard to the recirc pump, I'd like to find a pump that would allow 400 psi case pressure, 16gpm flow.

AJ


AJ,

You probably would be better off to call somebody like Ray Gingerich. With the size of equipment needed you're going to have more invested in equipment than it would cost to buy one of Ray's units. Maple Flats has one of his units and he has the contract information. I built a much smaller version which I could do economically, but if you're in the 100 to 250 GPH range it's going to be more difficult to beat Ray's price.

To answer your questions, there are no easy rules of thumb that will work for every case. You can use one pump to handle both pressure and recirculation. It's a little less efficient based on power consumption, but one pump will definitely work. The membrane manufacturers tend to keep the data on permeate flow vs. pressure out of sight because they have patents on their particular technology. Not sure about your pump question and the 30 PSI. Is that maximum suction or inlet pressure?

[AJ Peacock]

Dave,

How is your unit plumbed during wash and during rinse? Basically, which pump is used during each of these operations?

Thanks for you very useful response,
AJ


AJ, I wanted to chime in because what you are building is basically what I have in my Small Bros R/O from the late 80's. It has the same procon pump and a similar feed pump. I am also running two xle 4040s now. I can get a permeability test at 55 degrees and 200 psi of 210gpm when the system is clean. I have great luck running it at lower pressures around 200 at the beginning of the day and up to 300psi when things get dirty. Mine is set up in series and the best I can do is about 50 to 60% in one pass because it has no recirc pump. But it does have a recirc valve. This essentially accomplishes the same thing as having another pump. It's a double valve setup actually, with a ball valve(which is closed for cleaning), and a parker(needle) valve for fine tuning the flow. When concentrating it lets the concentrate output return to the inlet of the procon pump giving you the recirculation. You adjust this needle valve and the main concentrate output valve to get the desired pressure and concentrate level by reading the flow meters. Using this method, I can easily get the 75% water removal I want in one pass and it keeps the flow up through the membranes. The overall flow rates of both concentrate and permeate are lower using this method, so having an additional recirc pump would improve the flow I assume, but it works. The other method which works well for me is to send the concentrate back to the holding tank and recirculate it that way until the concentrate output has increased to the desired percentage. Then you just divert the concentrate to the feed tank for your arch. I can make more permeate per hour this way which is how you should look at it. The second method has to be monitored more because as the sap gets more and more concentrated the pressure goes up and up. I have no high pressure shutoff, only a low pressure cutoff switch for when I run out of sap. I also had to set up a wash tank and I'm changing my 10"pre-filter to a 20" one. (5 micron filters are plenty) Hope this was a help to you and best of luck!

[jcyphert]

But it does have a recirc valve. This essentially accomplishes the same thing as having another pump. It's a double valve setup actually, with a ball valve(which is closed for cleaning), and a parker(needle) valve for fine tuning the flow.

would you be able to post a picture of that that looks like? A part number for the recirc valve would be GREAT!

Thanks!

[TunbridgeDave]

This thread from a couple years ago has a picture of my R/O b4 I had it figured out.

http://mapletrader.com/community/showthread.php?14709-Recirculating-Valve&highlight=recirculating+valve%3F

As far as the needle valve I just grabbed this link off the webb to show what it looks like:

http://www.mrostop.com/nv109p-4-parker-brass-needle-valve.html

As far as washing/rinsing -vs- concentrating, the flow though the system is the same, using the same 2 pumps all the time. The only difference is you shut the recirc valve for washing/rinsing and you run the system at zero pressure to get max flow through the concentrate side of the membranes.

Have you shopped around for the membranes, pumps, flowmeters, fittings?

[AJ Peacock]

This thread from a couple years ago has a picture of my R/O b4 I had it figured out.

http://mapletrader.com/community/showthread.php?14709-Recirculating-Valve&highlight=recirculating+valve%3F

As far as the needle valve I just grabbed this link off the webb to show what it looks like:

http://www.mrostop.com/nv109p-4-parker-brass-needle-valve.html

As far as washing/rinsing -vs- concentrating, the flow though the system is the same, using the same 2 pumps all the time. The only difference is you shut the recirc valve for washing/rinsing and you run the system at zero pressure to get max flow through the concentrate side of the membranes.

Have you shopped around for the membranes, pumps, flowmeters, fittings?

Dave, thanks again.

When you wash, do you wash with a Soap/Lye solution? Does it just go past the membranes once, or do you capture/recirculate it through the entire system for a few minutes?
I can see that a full rinse is just open up the concentrate valve and put permeate through the system to rinse the membranes. Is this exactly the same as when you use a Soap/Lye solution?

I've started pricing parts, but don't have my exact Materials list finalized yet. We'd really like to include a recirc pump in the system, but haven't been able to figure out which one yet. If someone with an RO could send me a part# for the recirc pump they have, I'd really appreciate it. The biggest problem we are having is in trying to find a recirc pump that is rated at 400psi or higher case pressure.

Thanks again,
AJ

[TunbridgeDave]

I use the Leader soap for Filmtec Membranes. When you wash with soap you return both the permeate and the concentrate to the wash basin and circulate it through the system for a period of time. The important thing is to heat the wash solution up to around 113 degrees. That activates the soap. New machines have a built-in heater, but I am currently using a bucket water heater from Tractor supply (1000W). It takes a while and there is no thermostat on it so I'm looking for something better. You can also do a non soap wash, everything is the same just without the soap. Bringing the water up to 113 releases a lot of the gunk from the membranes. I say water, but ONLY USE PERMEATE for washing and rinsing.

I haven't looked into a recirc pump b4, so I can't help you there, but I do have some sites for other parts. Call Joe at Atlanticro.com for the best prices on membranes, housings and he has the procon pumps. I got replacement flowmeters from Allforwater on ebay. FiltersFast has good deals on the sediment filters. And USplastic.com has the high pressure nylon tubing and fittings like I have on my machine.

[JoshStamp]

AJ,

You probably would be better off to call somebody like Ray Gingerich. With the size of equipment needed you're going to have more invested in equipment than it would cost to buy one of Ray's units. Maple Flats has one of his units and he has the contract information. I built a much smaller version which I could do economically, but if you're in the 100 to 250 GPH range it's going to be more difficult to beat Ray's price.

?

I know Ray has a good price and a good looking system, but I really don't like to see all the people who run around discouraging others from trying this. I drove out and looked at Ray's ROs and realized they're well built, elegant, and not rocket science. I started pricing all the "big stuff" to essentially duplicate his 250 unit (2 four inch membranes) and ended up with about $1500. Rays unit is $3200 plus shipping (unless you go get it). If this guy WANTS to build his own, I think we should offer all the help and support we can instead of telling him to stop. (I didn't hear "I wish I could find an RO of this size", I heard "I want to build an RO".). Just my two cents.
Having looked at Rays units, I see a couple of areas for improvement. He uses a high pressure pump at around 4000 psi (for a car wash or something). That's way more "juice" than you need for an RO. A medium pressure pump (250-300 psi) is cheaper and needs a way smaller miter. You can save a bunch with a smaller pump and motor. Check out fluid-o-teck and procon for pumps. I bought my motor at Harbor freight for around $90 (with a sweet 25% off deal). My pump only cost me $189. I know one of Rays pumps will run $500+ and require a mother twice the size of mine.
Now- Ray makes a great product and I've never heard a bad word about them. He's also a really nice guy. If you want to buy an RO, you'd be silly not to call him first (but do it this week 'cause he's at least 100 units behind right now and will stop taking orders on Friday). But, if you're a "tinkerer" and you want to do this, it's more than do-able. Don't let the fact that there's an existing product make you give up. Otherwise we'd all be using DC current and listening to our TV shows on the radio.
Sorry for the rant. I started looking into this and got the same message. There's a difference between "want to buy it but can't so I have to build it" and "I want to build it cause it sounds fun".

[wiam]

I know Ray has a good price and a good looking system, but I really don't like to see all the people who run around discouraging others from trying this. I drove out and looked at Ray's ROs and realized they're well built, elegant, and not rocket science. I started pricing all the "big stuff" to essentially duplicate his 250 unit (2 four inch membranes) and ended up with about $1500. Rays unit is $3200 plus shipping (unless you go get it). If this guy WANTS to build his own, I think we should offer all the help and support we can instead of telling him to stop. (I didn't hear "I wish I could find an RO of this size", I heard "I want to build an RO".). Just my two cents.
Having looked at Rays units, I see a couple of areas for improvement. He uses a high pressure pump at around 4000 psi (for a car wash or something). That's way more "juice" than you need for an RO. A medium pressure pump (250-300 psi) is cheaper and needs a way smaller miter. You can save a bunch with a smaller pump and motor. Check out fluid-o-teck and procon for pumps. I bought my motor at Harbor freight for around $90 (with a sweet 25% off deal). My pump only cost me $189. I know one of Rays pumps will run $500+ and require a mother twice the size of mine.
Now- Ray makes a great product and I've never heard a bad word about them. He's also a really nice guy. If you want to buy an RO, you'd be silly not to call him first (but do it this week 'cause he's at least 100 units behind right now and will stop taking orders on Friday). But, if you're a "tinkerer" and you want to do this, it's more than do-able. Don't let the fact that there's an existing product make you give up. Otherwise we'd all be using DC current and listening to our TV shows on the radio.
Sorry for the rant. I started looking into this and got the same message. There's a difference between "want to buy it but can't so I have to build it" and "I want to build it cause it sounds fun".

If there was a thank you button I would use it. A lot of maple stuff is overpriced. And building an RO is not a big deal

[JoshStamp]

If there was a thank you button I would use it. A lot of maple stuff is overpriced. And building an RO is not a big deal

I joined this forum last spring 'cause I wanted to build an RO. I got a whole lot of "just buy one of Rays" when I didn't want to buy one- I wanted to build one! I just want to be the voice shouting "research it and try it". Lots of people build their own computers, and I think that's way harder than an RO, but the same basic idea- a bunch of off the shelf parts put together in a specific way. It's not magic, and its not rocket science.
After I got discouraged here, I joined sugarbush.info and never once got told to "just go buy it". Lots of helpful people there. I'm sure people here are trying to be helpful, but I think sometimes telling people how hard something is can be discouraging instead of helpful.
On another note, my IPAD doesn't seem to like the word "motor". First it was miter and then it was mother. Sorry if that was confusing.

[spud]

Some people are very mechanically inclined and building an RO would be a piece of cake. What's tough for some is very easy for others. With enough rolls of duck tape on hand how could anything go wrong?:lol: I know Thad built a RO last season. You might want to hook up with him. Using PM is another way of weeding out the nonsense and only dealing with people that know what they are talking about. Good luck to you and welcome to Trader.

Spud

[bowhunter]

Josh, when you ask for advice that's what you get....sometimes it's good advice and sometimes it's not. Building an RO isn't that complicated, but it also isn't a matter of buying some stuff and hooking it all up. There are people on this forum who have wasted a lot of time and money experimenting with something they didn't understand very well. There is a lot of good information available on RO. Dow chemical has a really nice website on designing RO units, although it's not specific to maple syrup, in addition there are at least a half dozen people on this forum who understand RO and have built units successfully and I know they'd be willing to help you. The mechanical construction of the RO is not the complicated part, it's getting the right RO membrane, the right size pumps to match the membrane, etc. Good luck and here's a link to the Dow design site......

http://www.dowwaterandprocess.com/support_training/literature_manuals/lm_techinfo/designstps_balance.htm

[Bruce J Stuart]

How do I get ahold of Ray. Im looking for an RO.

[bowhunter]

Here's the phone number for Ray listed on another thread. I believe you leave a message and he calls you back. His phone number is 440-422-3047.

[bairdswift]

I have one on order, ray said it's getting a little late but will try to pull one together for me. Been super busy he said and now he needs to start on his sugar woods.

[madmapler]

Regarding PM's. You should remember that you got your RO education from posts on the trader. I personally have learned so much about sugaring by reading and asking questions on this forum. Teuchtars RO plans are a perfect example. You simply extract the information that you need. I appreciate any positive input. If it does'nt help me it may be what someone else is looking for .PM's are good for some things, especially irrelevant subjects or maybe contacting a member with a question who is offline at the time as I recently did. He responded to my question through the forum and I respect that. If you PM about things that could be of benefit to others, you're really not giving anything back.

[stoweski]

Ray is not taking any more orders for this season at this point. Just spoke with him today and he said he's looking at May delivery.

He does have a 50gph unit that he will be producing and said he is looking into a $500 unit for backyard producers. No idea what the GPH is or how many taps it will handle.

Nice guy to talk to with a lot of good information.

To sum up the presentations at Verona... RO is the way to go!