Rick Morel wrote:
On Mon, 20 Apr 2009 08:22:29 -0700, wrote:
snip
snip
BTW, the poor little creature would implode, not explode.
Well, considering its fluid filled, how would it implode? It will be
lysed in either event.
Definition of lysed: The disintegration of a cell resulting from
destruction of its membrane by a chemical substance, especially an
antibody or enzyme
This is *one* definition. There are a number of others, and it is
commonly used for any action, mechanical/chemical/biochemical, that
ruptures the cell wall/membrane releasing the cell contents. It's from
the Greek "lysis" which just means a loosening, setting free, releasing,
or dissolution.
I honestly don't see how this would apply, unless it's a normal event
of decomposition? Is that it? I plead ignorance and welcome any info.
Yes, it is primarily through decomposition. As a biofilm forms on the
membrane (a layer of growing critters), the base, or underlying
organisms get farther and farther away from the source of nutrients (the
water flow) and they die. They then decompose, but instead of getting
flushed away by the water flow, their detritus gets trapped by the layer
of living and dying bugs above them. More food for the growing bugs.
Implode/explode. Okay, I'll go with both are impossible because it's
fluid filled. This then negates any effect of high (or low) ambient
pressure in either event, so that argument is thrown out.
snip
Again, all this is flushed out after a few minutes. It's simply a
matter of rejecting the first few minutes of product water.
Dumping the first few minutes of product is always a good idea.
Actually I would say it's a necessary idea. Wait, that reads
sarcastic. I don't mean it that way. I simply mean that I think it's
a necessary part of using an RO system.
Depends on whether or not you want your first drink of the day
"fortified" or not ;-)
Rather than play theory, here's the results of my real world
experience cruising and supplying water from RO:
Well, it's not theory. It's 25+ years experience with qualifying high
purity water systems, all of which utilized RO as one part of the
purification process.
snip
Don't get a too big watermaker. Size it to run at least a couple hours
a day, and run it every day to top off the tank. Membrane fouling and
all that bad stuff happen when they're idle.
Happens whether they're idle or not, but your point is well taken. 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. Stagnant water is *always* a bad idea...
It bears repeating. If you don't run it every day, or at least every
two or three days, you will have problems. Do the biocide treatment
(pickle it!) if you're not going to run it for more than a few days.
Thousands (tens of thousands? hundreds of thousands?) of people drink
RO water every day. On boats, ships, islands, Israel, and now
California from processed sewerage water. I guess some get sick from
it. It would be interesting to see what percentage compared to those
that get sick from city water and bottled water.
I doubt you'll find *one* case of sickness from drinking water made from
a properly maintained RO system. But it does bear repeating that RO is
a very good incubator for water bugs if not maintained and operated
sensibly. Not that hard to do as you obviously have experienced.
Keith Hughes