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Rick Morel

On Tue, 21 Apr 2009 22:03:55 -0700, wrote:

And I *still* say you must have been bitten by an RO unit as a child... :-)

Keith Hughes

I think you're right, Keith! Larry is apparently just a tad fanatic
about drinking water :-)

Keith wrote in a previous post:
My
experience is with units in the 2000-3000gph range, typically running
24/7 with treated city water as feed. Still require routine cleaning,
and biocide treatment.

I'm curious. Do these systems use the same 10% recovery rate?

More curiosity points...

I wonder how surface area, volume, etc. scale up. That's about 1,000
times as much product water, so does that mean surface area of the
membrane is 1,000 times more?

What's the difference between seawater, brackish water and fresh water
membranes? I've read it's the permeability, but are the "holes"
smaller or larger for the seawater compared to the fresh water? Or the
same size; is it the pressure rating instead? Is the seawater more or
less prone to fouling than the fresh water?

No answers required. Just wondering.

The bottom line, in my opinion, is that an RO system on a cruising
boat, especially on one like ours that spend months "away from
civilization", is the best answer for all fresh water needs. We're a
sailboat with solar panels and a wind generator that keep the
batteries up.

Yes, it does require care and work. I would say it's more work taking
off the sailcover and replacing it than to maintain the RO system.
Like the sailcover, if you don't do it, you'll pay for it. In the case
of the sailcover, a new mainsail; in the case of the RO a new
membrane.

Rick Morel