My RO is vertically oriented and is on wheels. I store it in a small heated room and roll it out to use it. I often run it thru once sending it to the head tank, usually about 2% up to 8%, then I recirculate from the head tank thru the RO again, but I start boiling at the same time. I have a site gauge on my 150 gal head tank, when the level gets down to about 25 gal I start sending new sap to the RO and run the pressure so I get slightly more concentrate than I'm removing in the evaporator. If the head tank gets over about 100 gal I switch back to recirculating from the head tank. Doing it this way my sugar levels range from about 8% up to 15% in the head tank, my average is about 11-12%. If my RO would do 14% in one pass, I'd do that and just run the RO to match the evaporator, I can't keep up with the boil if I try for anything over 8%, If I get a little low i the head tank, I turn the pressure back so I only get about 7%. At 7% my RO makes more concentrate than the evaporator boils away so the head tank fills more. That 15% I got was near the end of a boil when I had no more sap left so I just let the RO recirculate until it got down to just under my shut down mark on my site gauge, that is when I add the last wood. At that point I ran permeate to push the sweet from the membranes which brought it to just over the shut down mark.
To match my boil I need 1.3-1.4 gpm of concentrate (I get 80-85 GPH evaporation).
Last edited by maple flats; 04-28-2019 at 10:16 AM.
Dave Klish, I recently ordered a 2x6 wood fired evaporator from A&A Sheet Metal which I will be converting to oil fired
Now have solar, 2x6 finish pan, 5 bank 7x7 filter press, large water jacketed bottler, and tankless water heater.
Recently bought another Gingerich RO, this one was a 125, but a second membrane was added thus is a 250, like I had.
After running a 2x3, a 2x6, 3x8 tapping from 79 taps up to 1320 all woodfired, now I'm going to a 2x6 oil fired and a 200-425 taps.