Well im sure you are correct but either way in the world of sewerage that
is what the issue is with diaposing used ferric chloride.
On Mar 10, 2013 11:31 PM, "Todd F. Carney / K7TFC" <k7tfc@...> wrote:
> ∗∗
>
>
> Neither iron nor copper are actually "heavy." Atomic number is part of the
> definition. Fe (iron): 26 / Ni (nickel): 28 / Cu (copper): 29 / Zn (zinc):
> 30. Each of these needed by all life (in the proper quantities, of course).
>
> Now, these buggers ∗are∗ heavy: Hg (mercury): 80 and Pb (lead): 82. Useful
> but nasty metals.
>
> Sorry for the quibble. Heavy metals is commonly used to mean "toxic metal
> compounds." That's okay. I need coffee. I'll feel better.
>
> 73,
>
> Todd
> ----------------------------------------------------------
> K7TFC / Medford, Oregon, USA / CN82ni / UTC-8
> ----------------------------------------------------------
> QRP (CW & SSB) / EmComm / SOTA / Homebrew / Design
>
> On Sun, Mar 10, 2013 at 11:30 AM, Charlie Taylor <scubadogct@...
> >wrote:
>
> > in my opinon the preasence of ferric is not the issue. It is tje heavy
> > metals that is the peoblem.
> > On Mar 10, 2013 1:03 PM, "Dave Sage" <davesage12@...> wrote:
> >
> > > ∗∗
> > >
> > >
> > > Perhaps someone with some knowledge on public works and sewage
> treatment
> > > can
> > > clarify this for me.
> > >
> > > I guess it must be the copper in the ferric chloride etchant that we
> > > dispose
> > > of that is the problem - is that correct? Is there actually copper per
> se
> > > any more after the reaction of etching?
> > >
> > > I'm pretty sure somewhere in the sewage treatment process, after gross
> > > solids are removed, the water in the sewage system is sent to settling
> > > ponds. While in the ponds ferric chloride is added to act as a
> flocculent
> > > i.e. an agent that causes solids to gather together in clumps for easy
> > > removal. If this is the case, would it make any difference if there
> were
> > > some ferric chloride in the system to begin with (from flushing etchant
> > > down
> > > the drain)?
> > >
> > > [Non-text portions of this message have been removed]
> > >
> > >
> > >
> >
> >
> > [Non-text portions of this message have been removed]
> >
> >
> >
> > ------------------------------------
> >
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>
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