needing help with ro

[Rodshobbies]

looking for some input on what I'm doing wrong . we have a small commercial ro system that came out of a restaurant for there water . it's a 25x40 vessel with a procon pump. We have two pre filters before the unit. Our sap is coming in at 1.3 and our first pass can get up to 2% and on a second pass we are lucky to get a half a percent and even after our 4 pass we might get 3 to a 3.5%.looking for ideas

[Urban Sugarmaker]

What kind of membrane is inside and has it been maintained? Any idea what your flows and pressures are? Are the prefilters new and clean? Please tell us more about the unit.

[Rodshobbies]

we are running a new this season filmtec BW30 which was recommended running pressure is 240 -250 pre filters are also new first one is a 30 micron and the second one is a 5 micron13681

[Urban Sugarmaker]

It seems like it should be concentrating more. I don't see any flow meters but you could time your flows using 5 gallon buckets. If the concentrate flow is much higher than permeate flow, then that's why you are not removing a lot of water. In that case you will need to restrict the concentrate flow if I'm not mistaken. That's how mine works.

Where are you restricting flow to generate pressure? I see a ball valve near where the feed to the membrane is but it looks that is for drainage.

I didn't see anything in the DOW documentation either that makes me think this membrane would not work.

[Rodshobbies]

How much pressure do I darn apply . There is a ball valve on the to head of the vessel .the head is off in the picture as we have to drain and remove the membrane after each day to protect it from freezing.

[Rodshobbies]

I figured its time for an up date .gave up on the ro for 2017 and went for it again in 2018 . After lots of reading and getting frustrated I starting increasing the pressure to the membrane and holy smokes I drove up the sugar content. Now with sap coming in at 1.5% I can easily take it to 5% one pass . Only problem now cant keep up to rate of evaporationso now for 2019 I added a second vessel and membrane of the same side .Only boiled on the weekend 200 gallonsbut seems to work excellent. Processing approximately 38 gph. Very happy