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Re: Urethane Systems House
---A while ago, Bill Wilson wrote:--------------
>A colleague is settling an enforcement case with a small chemical company,
>and would like to have the company explore P2 options as part of a
>supplemental environmental project (SEP). Unfortunately, we haven't been
>able to shed much light on the options due to our (total) unfamiliarity
>with the processes and practices at such a facility -- here's how he puts
> "The facility is a compounding and blending house for aromatic
>urethanes. This type of operation is also known as a "systems house," as
>they produce urethane systems for other facilities' use. The urethane
>system consists of two sides, an A and a B side. This facility purchases
>the A side, consisting primarily of diisocyanates, ships it in on railcars,
>tranfers it to holding tanks, and repackages it for sale in conjunction
>with the B side. The facility compounds the B side. The components are
>polyols, blowing agents (HCFC 141B), catalysts, plasticizers, fire
>retardants, pigments, surfactants, and various extenders like ethylene
> "The facility claims that there are no regular emissions during this
>blending and packaging process, but nontheless manages to go through about
>20,000 lbs a year of dichloromethane to clean up the floor.
> "Any suggestions on potential projects a facility like this could do
>to minimize its impact on the environment would be appreciated."
>Does anyone have enough familiarity with such a facility to make
There are a number of potential P2 practices to check for at such a
facility. For example:
1. how are the compunding reactors cleaned? What is done with the
cleaning waste? Is it reincorporated into product?
2. The facility claims there are no regular emissions during processing
-- is this because the mixing unit is connected to a thermal oxidizer of
some sort? I would definately expect volatile emissions during the
compounding process. If there is no control equipment, one P2 option would
be the use of condensors for each reactor. A company I am familiar with got
fined for not having proper air permits and was force to do BACT -- which
meant installing a thermal oxidizer. They connected their six reaction
vessels to an existing oxidizer located roughly 125 yards away. However,
this long duct work now acts as a condenser and many of the less volatile
componetns (e.g. n-methyl perrolidone) condense in the duct work and drip
out onto the floor and outside on the parking lot. Condensors would have
been a much better option.......
3. What type of quality control do they have on their batch processes?
One of the biggest sources of waste in such an operation is bad batches that
firms spend hours on trying to rework -- often it ends up as hazardous waste
which is doubly costly. Not only does the material have raw material and
waste disiposal costs, but there is all that labor already put into it.
4. why is the floor getting dirty and why are they using
dichloromethane to clean it up? There are a number of substitute materials
that are less toxic that they could use for clean up purposes. I did some
research with a urethane manufacturer sponsored by the Massachusetts Toxics
Use REduction Institute. We found a few terpines that actually clean
uncurred and semi-curred urethanes very well. But the real opportunity is
to figure out why there is such a mess to begin with. Perhaps a fish-bone
diagram analysis would help the company get to the root cause of the problem.
Sorry for responding so late to your post. .... Your message has been in my
in-box for weeks and I keeep on meaning to get to it. Anyhow, there are
many other possible changes you could make so feel free to call if you'd like
Timothy J. Greiner MBA, MCP
2 Emily Lane
Gloucester, MA 01930