Sorry, Franklin, it is not semantics. You are putting forward a scientific statement
and the essence of science is precision. Hopefully, your "crystalline growths" were
mostly calcium/magnesium hydroxides, carbonates and hydrocarbonates, which are common
in many tap waters, rather than chlorides. Calcium chloride is physiologically not very
good, especially for children, and excess sodium chloride (>~400 mg/l) is worse for
hypertensive patients.
Interestingly, chlorination can produce minute amounts of hydrochloric acid if the
water has a heavy microorganic content and this may react with dissolved calcium
hydroxide (lime) to produce calcium chloride, but the quantities involved are
negligible. Care should always be taken to introduce sufficient chlorine to kill off
the microorganisms but not sufficient excess chlorine that the water becomes
objectionably odoriferous. It is for this reason that UV irradiation is sometimes
preferred, by itself or as a pretreatment before a milder chlorination, as a biocide,
e.g. in desalination plants for potable water. Incidentally, the NaCl limit for many
desalination plants is ~400 - 800 mg/l, but this is often mixed with ground water or
other sources in the reservoirs, to dilute it down to under 200 - 300 mg/l NaCl. About
800 mg/l is the threshold of taste.
Anyway, not all municipal water is bad. In Scotland, for instance, many highland lochs
have negligible TDS. In fact, Loch Katrine is a major reservoir for Glasgow and they
actually add some lime to it because the water is so soft, with a pH of about 5,5, that
it corrodes the cast iron conduits (not to mention kid's teeth and bones). In Glasgow,
before the 39-45 war, over 1/3 of the kids had rickets in some degree or other because
the water was so poor in calcium and they drank little milk (heavily depressed area and
milk was beyond the purses of many households). I know some plants in some parts of
Scotland that use unpurified water for cleaning PCBs, quite successfully, but this is
the exception that proves your generalisation.
Brian
Franklin D Asbell wrote:
> Semantics, or the wrong choice of word, contaminates in the city water
> rinse used at that company caused crystalline growth as evident by SEM
> and Auger analysis.
>
> The point being city water....bad!!!
>
> ~grin~
>
> Sorry to stir the pot...
>
> Franklin
>
> ##############################################################
> TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c
> ##############################################################
> To subscribe/unsubscribe, send a message to [log in to unmask] with following text in
> the body:
> To subscribe: SUBSCRIBE TECHNET <your full name>
> To unsubscribe: SIGNOFF TECHNET
> ##############################################################
> Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
> information.
> If you need assistance - contact Keach Sasamori at [log in to unmask] or
> 847-509-9700 ext.5315
> ##############################################################
##############################################################
TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c
##############################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following text in
the body:
To subscribe: SUBSCRIBE TECHNET <your full name>
To unsubscribe: SIGNOFF TECHNET
##############################################################
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information.
If you need assistance - contact Keach Sasamori at [log in to unmask] or
847-509-9700 ext.5315
##############################################################
|
