"Geoff Schultz" wrote in message
6...
So, my questions are as follows:

1) Are the calculations that I listed above correct? 2) How can I be
producing water at the rate that I am?
3)What determines the prodution rate of a membrane assuming that it's at
800 PSI?
4) Does anyone have a Little Wonder system that actually produces at the
speced rate?
5) They claim to need to test the pressure vessle. What could they
possibly be looking for?

1) Those are the same formulas I am working from. Pretty standard. You
really need .6HP to supply 1.1 GPM @ 850PSI. You can't get more than about
28 GPH @800PIS out of 1/4HP
2) Sounds like you are overdriving the membranes and they are going to
scale up a lot faster. I ran the numbers you gave through Rosa, Dow's
design program. Even at the designed 10 GPH product @ 15% the concentrate
flow is marginal at best. At half that supply rate concentrate flow is way
low.
3) Salinity of the water, temperature, condition of the membranes,
configuration of the membranes, pressure and rate of feed water. Are the
membranes plumbed in series or parallel? Is the pressure between 800 and
850PSI? Are you pulling from a brackish river outflow or open seawater?
4) Built my own
5) I have no idea.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
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