Running RO overnight

[Rich R]

We are constantly trying to streamline our operation. We have a Next Gen 2.5" RO and wondered if we could run it overnight. Has anyone here done that?

[David Wayne]

Not familiar with your RO and I am just a small hobby producer. But I have a RO bucket that runs 18-20 gallons an hour and I run it overnight feeding the concentrate
back into the raw sap, if I have enough to start with. 200 gallons 10 hrs. would remove 9 gal. of water/hr so 90 gal. while I sleep leaving me with 110 that I then run again into the evaporator. The actual numbers are a little less because as it gets more concentrated it slows down. But I would think the same would work for you with your own capacity numbers. Hope this helps.

David

[Openwater]

I have a RO bucket that runs 18-20 gallons an hour and I run it overnight feeding the concentrate
back into the raw sap, if I have enough to start with. 200 gallons 10 hrs. would remove 9 gal. of water/hr so 90 gal. while I sleep leaving me with 110 that I then run again into the evaporator. The actual numbers are a little less because as it gets more concentrated it slows down.
Hey David,
I also have an RO bucket that I upgraded to 3 membranes that I put on a board, so it's basically the RB15 as well.
Could you tell me a little more about how you RO your sap right in the sap tank? I typically collect anywhere from 10-40 gallons per day and RO it down in batches taking it from 1% to 2% to 4% and sometimes run again to get it to 7%, but I'd prefer to just recirculate the concentrate like you described and let it run until reaching the sugar % you want. Does this recirculation damage the membranes at all, or do they just automatically slow the concentrate and permeate flow automatically as the tank gets higher sugar %? I've been thinking about trying to do this, but was nervous about fouling my membranes (not cheap) or something worse like burning out the pump.

[David Wayne]

I put mine on a board this year, much better than in a bucket. This is my second year doing this and I am running the same membranes as last year, they are doing fine.
I have only done it 3 times this year though due to not enough sap, maybe 600 gal. total this year. With 40 gallons you would need to keep an eye on it, in 2 hrs. you will have removed +- 18 gal. if each line is running 9gph. And as it concentrates it slows on its own, it may drop to 12-14 gph. total sap run. In my figures above I will be at about 3 1/2 percent the next morning, then 7 into the evaporator. My tank is a 265 gal. IBC tote and permete water goes in another tote to use for cleanup. I also bought the flow meters this year so I can accuratly know how much I am running per hour.

[Openwater]

I'm never really sure how fast/slow my flow is. I just measure the sugar % of the sap and adjust needle valve until concentrate is double the original sap sugar %; then I just assume the concentrate/permeate lines are running 50/50. What brand/model are your flow meters? Do you just have them installed on the concentrate and permeate lines? Or somewhere else on the set-up?
Thanks for the help

[David Wayne]

Ordered them through the ro bucket ZYIA, the concentrate one has a flow valve so you don't use the current needle valve.
You should at least use two pint jars and fill them at the same time with permete and concetrate. The manual warns not to let
the permete outrun the concetrate.

David

[TheNamelessPoet]

Ordered them through the ro bucket ZYIA, the concentrate one has a flow valve so you don't use the current needle valve.
You should at least use two pint jars and fill them at the same time with permete and concetrate. The manual warns not to let
the permete outrun the concetrate.

David

I hold the 2 outputs together, and I fiddle with it until the needle valvs until the stream changed from a stream to drops the same distance away from the end of the tube.

[littleTapper]

I run my RB20 kit overnight all the time. Pressure switch kills it if it's done pulling sap or something else causes a pressure drop. This is the fourth year running it and I have always done a 70:30 permeate/concentrate ratio.

[David Wayne]

little tapper, is this 4 years on the same membranes and how much sap have you processed with them and how much can you run before you have to flush them? On a good day (not this year) I might get 200 gallons a day so processing may be 14-16 hours, could they handle that? The manual says they will deteriorate much quicker
running that way.

[littleTapper]

little tapper, is this 4 years on the same membranes and how much sap have you processed with them and how much can you run before you have to flush them? On a good day (not this year) I might get 200 gallons a day so processing may be 14-16 hours, could they handle that? The manual says they will deteriorate much quicker
running that way.

Yup, 4th year on the original membranes. Monitoring them closely this year but no signs of issues yet. I don't get crazy yields but 1200 gallons/year is about normal. I run a lot of 200+ gallon batches through mine and they do slow down a bit toward the end of the job, but not bad. After the processing I give it a good long agitation cycle then a long flush with permeate.

[DRoseum]

You can run a low pressure recirculation loop with these ROs to reduce fouling and increase concentration output. Other threads on here cover the details, but there are advantages over recirculating back to the sap tank and over upping the pressure to get higher concentrations (not building up higher bacteria levels in sap tank and keeping recovery rates / fouling minimized).

Basically split the concentration output in half and route it back to a tee upstream of the pump input. Then you can run a higher permeate to final concentration output ratio while still keeping membrane recovery rates as low as possible and getting higher concentration levels.

[David Wayne]

I don't know what agitation cycle is

[wnybassman]

We are constantly trying to streamline our operation. We have a Next Gen 2.5" RO and wondered if we could run it overnight. Has anyone here done that?

Is it a 2.5" x 40" Next Gen? Do they recommend a flushing every 30 minutes like my 4" by 40" Next Gen? That would be my concern I guess, fouling of the membrane running it that long.