Thrift shop distiller $9
Larry wrote:
Keith Hughes wrote in news:46e62c2e$0$10300
:
Depends on whether your still is really effective or not. If you're
only condensing *steam*, i.e. not water vapor but gaseous steam, you
may
be correct. However, unless your still is a multi-effect (doubtful) or
uses some form of cyclonic separation (doubtful), and uses some form of
demisting (also doubtful), you don't have quite the assurance you think
you do. Almost certainly any organisms will be inactivated, but you may
still have endotoxin carryover.
There is no water vapor making its way out of the water trap in the top
of the boiler. Water doesn't run well uphill with no pressure.
Water vapor runs 'uphill' very efficiently, since it weighs much less
than air (ever see a cloud?). Water vapor - what you can actually see -
is not steam, it's water. And that vapor can carryover all kinds of
things if not removed.
There's
a special trap in the top to prevent it.
That's the point I was making - a simple demister like your still likely
has is not nearly as efficient as you may think it is. Hence the use of
cyclonic separators in many (depending on design) industrial stills, to
remove vapor and low molecular contaminants more effectively without a
huge hit on distillation efficiency.
I've never heard of endotoxin vaporizing only the various...enes like benzene, xylene, all carbon-
It doesn't vaporize, it becomes entrained in the water vapor.
based that are trapped by the activated carbon filter the water coming
out passes ever so slowly through so these distillable petroleum products
attach themselves. You can easily taste these in the un-carbon-treated
distilled water. The taste is significantly different after carbon
filtration.
Another sign is my water will not conduct electricity, even at 2000 volts
from my megger. Distilled water is an insulator uncontaminated.
I think you'll find that distilled water (unless it's distilled in
glass) will have a resistivity of about 2 megohms/cm, versus DI water at
~18 megohms/cm. There's more than enough ions released by the stainless
to drop the resistivity (increase conductivity) significantly when
compared to DI water.
ONE
grain of table salt just touching the water on the other side of a
container of it and ZOOM!....The current goes WAY up! I cannot get my
polycarbonate containers to get the TDS below about 1.9 ppm. I think the
containers themselves are being eaten by the really corrosive distilled
water, which causes a tiny leakage in the electrical test.
RO water has its place. But, there ARE bad problems with RO if it is not
meticulously maintained. And, it takes a lab test to see if it's safe
boaters don't have, placing WAY TOO MUCH FAITH in the integrity of that
membrane, I think.
You say that like everyone is feeding wastewater into their RO. With
simple maintenance, they can be very effective, and very safe,
especially when you're talking about desalinization. But take a look at
commercial (real) stills and look at the performance specs. Check
Stilmas, Steris/Finn-Aqua, Mueller, etc. You'll find that they will
provide a 3-log reduction of endotoxins, and they will not effect a
significant reduction in over TOC, so you can't dump sewage in a still
and be assured of pristine pure water coming out. Yes you *can* do that
with distillation, but you have to accept a 10 or 20 fold reduction in
efficiency to ensure that absolutely *no* vapor is carried over. That
doesn't sell well.
I'm not saying that your still is not effective, and not a good way to
make clean water. It's just not nearly as effective and foolproof as you
want to claim.
Keith Hughes
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