[Dioxin-l] Thank you Connie Hansson

[David Ross]

I find the contribution by Connie Hansson to be the most cogent and
thoughtful contribution to the list I have seen in the short time I
have been a member.  Thank you for it.

Her posting prompts the following response:  For the record (and as I
had thought I had made clear earlier), while now retired my
professional experience and present motivation are directed to
alternatives to combustion for the destruction of halogenated waste. 
We all agree that dioxin and related materials are toxic, and that
classical incineration (i.e. combustion) of chlorinated waste is a
significant (sole?) source.  And for very good technical reasons we
cannot make incinerators cleaner and cost effective at the same time.
There are moreover political elements to this issue as well, as
Connie suggested. 

It is the case, however, that there do exist combustion alternatives
that can be developed to commercial scale to be at least as cost
effective as incinerators.  In such systems, which are not at all
exotic and use common materials, dioxins cannot form (temperatures
too low), and indeed purposefully introduced dioxins are destroyed as
rapidly as other chloroorganics.  The products are NaCl, CO2, and
water.

There are therefore two paths to follow in my view:  i) Accepting
that the PVC industry and its cousins are huge and will not be
replaced, and that they are processes with very large quantities of
chlorinated waste-side products that are largely incinerated or
deep-welled, work to force a cleanup of the processes; and ii) since
there will inevitably be waste at any rate, work to affect
development and implementation of a combustion alternative for
disposal.  (The list of course is no place for product promotion, and
that is one reason why I have minimized discussing my background.  I
won’t go into specific alternatives accordingly, but will be pleased
to discuss the technical issues individually with interested
parties.) 

My guess is that this view will not be very popular with some list
members since I am not advocating elimination of all organochlorines
forever.  Rather I recognize that PVC and other chlorinated products
are with us like it or not, and they are in many ways useful to us. 
And while I cannot support the following statement with a citation,
my view is that replacement of those chlorinated materials we find so
useful today, including polymers, pesticides, pharmaceuticals, etc,
with halogen-free substitutes would be difficult if not impossible. 
But since a big part of the problem is their ultimate disposal, it
would seem that a replacement for combustion is a satisfactory route.

Finally, I don’t know the answer but I ask Connie:  Is not municipal
incineration where the feed is largely common C,H,O,N's and is
relatively chlorine-free ok?  Or are there problems in that arena
too?  

Michael


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