Watts Commercial RO

[bowhunter]

Has anyone on this forum tried one of these commercial RO units in maple sap processing? http://www.freshwatersystems.com/s-749-watts-r12-series-commercial-ro-system.aspx I saw them on Fresh Water Systems and they look really interesting. They have a 600 GPD and 1000 GPD unit that might be a good fit for small producers with 200-400 taps. The systems are real commercial equipment with all the bells and whistles. The 600 GPD unit has one Axeon HF 2 1/2 x 40 1000 GPD membrane in a stainless steel housing and a 1/2 HP Procon pump. It has needle valves on the concentrate and recycle so recovery can be manipulated between 15 and 75%. It costs about $2,200 delivered with pressure gages and flow meters. Although it's relatively expensive I know one guy on this forum who built a similar unit and spent about $1,500 on the parts. I believe all of the small commercial units offered by the maple equipment guys are quit a bit more expensive. I've contacted them to discuss use in maple sap processing. The only downside is 1) you would need a small booster pump to feed sap to the unit at 20 PSI and 2) it is limited to 90 PSI which will only get to 9.5%.

[wiam]

Unless there is some sort of recirculation on the membrane I think it will drop in flow pretty fast.

[bowhunter]

It has recirculation. I don't have all the details, but that's how they get to 75% recovery on tap water.

[markct]

Wiam said it exactly, water treatment Ro systems generaly dont have the volume of recirculation needed to keep the membranes clean when running sap thus causing them to plug rapidly and slow down permeate flow

[mellondome]

this system is almost exactly how most home builders are making their own.. 5 micron blue filter, procom pump, membrane or 2, and flow meters. With 2 2/5"x40" membrane , it is probably a $1800 build that will get you 80 gph with sap. there are a few who have complete write ups on this site or the other one with a build just like what you are buying here.

[bowhunter]

If someone has a write up on a system this size with actual performance data that they're willing to share I would love to see it. I'm working on a design for myself and have been getting a lot of good ideas from people on the forum. I've seen detailed plans on some smaller systems, but no real details on units this size. I know people are running systems they've built themselves.

I have a pretty good computer model based on Dow membrane data and it matches the performance of some of the smaller systems pretty well, but I don't have much information on the commercial membranes. The membrane suppliers are stingy with the detailed data sheets for the commercial membranes, particularly the pressure versus permeate flow relationship. Derating for lower temperature and osmotic pressure are no problem because all the membranes have about the same response and there's a lot of published data. H2O innovation has a good curve on fouling relative to % recovery which provides pretty good guidance on flow requirements to prevent fouling on sap.

I posted this question because I think the manufacturer could make some minor adjustments to this unit such as changing the Procon pump to get the right flow and possibly the membranes at very little difference in cost. I see a lot of guys on here doing trial and error trying to find something that works. Unfortunately some of them are spending a lot of money in the process. I imagine some are ruining the membranes and pumps because they aren't adequately designed. A lot of people don't have the time, mechanical skills or tools to put a good system together and this might be a very good option for them. It might cost them a little more than to make it themselves, but it might be worth the cost.

Any additional information would really be appreciated.

[markct]

The biggest thing it lacks is a high flow recirculation pump, the recirc pump on my cdl ro costs over 2k alone so not a minor change to make! And once you add one it puts the machine up in the price range of a maple sap ro anyhow.

[bowhunter]

That's a very good point. Do you know the flow rate on your recirculation pump? Is it 1000 GPH?

Dave

[maple flats]

I fail to see how 90 PSI will get you to 9.5% on sap. My RO needs just under 300 PSI to get 8% with cold sap. The $2200 you are looking at is so close to a Ray Gingerich 125 GPH and likely some others, that I'd look at his. In July 1011 his 125 was $2500. I got a 250 GPH at $3000 + $200 for 2 options, hi-lo pressure cut offs.

[bowhunter]

I haven't seen anything on Ray Gingerich RO units, but those prices are really low. The smallest unit Leader sells is $6,500 for a 50 GPH unit which is still too big for a lot of us really small producers. I can't believe he's sill selling at these prices. The components cost more than that retail. I'm looking for something in the 20-25 GPH range which I plan to build myself.

[Diesel Pro]

The Amish work very cheap. Lots of $12/qt syrup sales in my area and I'm sure some even less.

[markct]

bowhunter, yes the pump would be right around 1000 gph, its around 16 gpm according to the nameplate

[bowhunter]

Mark,

Thanks. I thought it was about a 1000 gph, so the total flow through the membrane is 5 times the feed rate. I'm trying to zero in on the recirculation rate on the commercial units. The smaller commercial RO units use one pump for feed and recirculation. I'm planning to do the same.

Dave

[wiam]

My 1996 Memtek was built with 2-4" membranes and has a flowmeter for recirculation and the manual says it should run between14-16. I added 2 more membranes and it washes better if I only wash 2 at a time

[bowhunter]

Thanks William, That looks like about the same recycle to feed ratio about 4 to 1.

Dave