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Chasefamily
10-19-2016, 03:16 PM
Alright, I have been crunching some numbers to try and understand the throughputs I may achieve depending on how I design my RO and the parts I choose. As of right now it is my understanding that the GPH are mainly determined by the high pressure pumps GPM and the Membrane.

Right now I am looking at the MES 4”x40 membrane that is rated at 2900GPD at 77 deg. I have been told to take a 2.6 reduction for sap that is 36 deg, so that brings that number down to 1115.38 GPD or 46.47 GPH which is at around 100 PSI I believe and will increase as I’ll be running more in the 200 to 250 range.
Also I have seen that the ideal recovery to reach is 15% in one pass or someone state a ratio of 6.7:1 concentrate to permeate. This is correct? Bases on this info I have seen and been told I have done some calculations and wondering if I am in the ball park

The scenarios are done with a 300 Gal @ 2% run and 1 pass
1st one with no recirculation
3.8GPM pump= 3.31 gpm C, .49 P, removes 25 GPH = 1.32 HRS run time to 261.2 Gal 2.47%
4.3GPM pump= 3.73 gpm C, .55 P, removes 33 GPH = 1.16 HRS run time to 261.7 Gal 2.47%
5.4GPM pump= 4.7 GPM C, .70 P, removes 42 GPH = 56 MIN run time to 261.1 Gal 2.47%
75% recirculation
3.8GPM pump= 3.31 gpm C, 2.4825 Rec .49 P, = 3.795 HRS run time to 188.42 Gal 3.42%
4.3GPM pump= 3.73 gpm C, 2.7975 REC .55 P, = 3.37 HRS run time to 188.5 3.42%
5.4GPM pump= 4.7 GPM C, 3.525 REC .70 P, = 2.67 HRS run time to 188 Gal 3.42%
Set RO to 40.8GPH Concentrate out .68GPM
3.8 79% Recirculation 4.27 HRS to 174.2Gal 3.4%
4.3 82% Recirculation 4.065Hrs to 165.85 Gals 3.6%
5.4 85.5% Recirculation 3.623 HRS 147.83 Gal 4.1%
35 GPH .583GPM
5.4 87.6% recirculation 3.897 Hrs. to 136.317 Gals 4.7%
25GPH .4167GPM
5.4 91.1% Recirculation 4.477 HRS to 111.946 gals 5.7%
Max flow for membrane 15GPM
40.8 GPH .68GPM 94.7% recirculation 1.9 HRS run time to 77.52 Gals 8.3%

Alright now that I have put out all the numbers, maybe someone that has a calculator that does this much easier before I make one. In which I am not even sure that I have done them correctly just read through some forums and came up with a bunch of different numbers. I would just like to know the correct calcs before I choose the parts in which I will purchase to build on. At the moment I am thinking a 1hp motor coupled to a procon pump from 265-330 GPH @250 psi and haven’t choose between 1 or 2 membranes as I am worried if I would have enough flow for 2, also think I can make it work without a recirculation pump?
At the Current moment I have about 450 taps on 3/16 nat vacuum and can only boil around 30-40 GPH

Sorry for all the random numbers, it’s kind of a mess. But thanks to anyone that spends the time to read through it, if it can even be understood. Just looking for any bit of help right now that I can.

Chasefamily
10-20-2016, 03:31 PM
Now I have been thinking how I could increase this unit if I choose to do so. I could by a bigger hp motor as well as higher GPH pump like a 660GPH although both of these seem to be expensive so I was thinking about putting two pumps in parallel to increase the flow. Also parallel and series with a 2nd membrane here is what I came up with. Also wondering if would need a recirculating pump to do these
(2) 228GPH @ 250PSI pumps, (1) 4x40 35GPH flow
7.6 GPM 6.62C, .98P, 91.2% rec, 3.199HRS run time to 111.9 Gal@5.7%
(2) 257GPH @ 250PSI pumps, (1) 4x40 35GPH flow
8.56 GPM 7.447C, 1.113P, 92.2% rec, 2.948HRS run time to 103.125 Gal@6.2%
(2) 257GPH @ 250PSI pumps, (2) 4x40 in Parallel 35GPH flow
4.28GPM 3.73C, .55P, 92.1% REC in each membrane, 2.971HRS to 103.921 Gal@6.15%
(2) 326GPH @ 250psi pumps, (2) 4x40 in parallel 35GPH flow
5.4GPM 4.7C,.7P, 93.7% REC, 2.521HRS to 88.2Gal@7.25%

257GPH pump @ 250PSI (2) 4x40 in series35GPH
1st mem 3.73C,.55P
2nd mem 3.25C,.49P
82% Rec, 3.08HRS to 107.76 Gal@5.9%
330GPH pump @ 250PSI (2) 4x40 in series 35GPH
1st mem 4.7C,.7P
2nd mem 4.09C,.61P
85.7% Rec, 2.641HRS to 92.393 Gal@6.9%
(2) 228GPH pump @ 250PSI (2) 4x40 in series 35GPH
1st mem 6.62C,.98P
2nd mem 5.76C,.86P
89.8% Rec, 2.064HRS to 72.183 Gal@8.8%
(2) 257GPH pump @ 250PSI (2) 4x40 in series 35GPH
1st mem 7.447C, 1.113P
2nd mem 6.482C,.965P
91% Rec, 1.88HRS to 65.73 Gal@9.6%
(2) 257GPH pump @ 250PSI (2) 4x40 in series 50GPH
1st mem 7.447C, 1.113P
2nd mem 6.482C,.965P
87.1% Rec, 1.717HRS to 85.87 Gal@7.4%
(2) 257GPH pump @ 250PSI (2) 4x40 in series 71GPH
1st mem 7.447C, 1.113P
2nd mem 6.482C,.965P
82% Rec, 1.533HRS to 108.75 Gal@6%

WoodButcher
02-19-2017, 12:09 PM
your mailbox is full. be sure to delete the sent folder mail as well.