Chemical Engineering December 2010 - 47

solvent Recycle and Reuse
S
1-Ethyl-2-pyrrolidone
Acetone
Decalin (Decahydronaphthalene)
Dimethyl sulfoxide
Ethanol solutions
(excluding specially denatured
alcohols)
Ethyl acetate
Ethylene glycol
Isoamyl alcohol
Isopropyl alcohol
Isopropyl alcohol (high water)
Methanol
standing the chemical waste disposal
process minimizes costs up front by
smoothing the transition from the
MSA to disposal and reuse.
ome waste disposal companies offer more sophisticated services, such as the ability
to recycle solvents. Examples of solvents that are typically recycled for reuse include
the following:
Revise #1 - 2/4/10
6:00 PM
Methyl ethyl ketone
Methylene chloride
N,N-Dimethyl acetamide
Naptha
N-Methyl-2-pyrrolidone
N-Propyl bromide
Perchloroethylene
Petroleum distillates
Propylene glycol
Tetrachloroethylene
Tetrahydrofuran
Toluene
Xylenes (ortho-, meta-, para-)
Communication
with the waste disposal
company has become even more critical
over the last few years due to increased
opportunities for chemical
reuse, recycling and tolling.
Reuse and recycle. Some hazardous
and non-hazardous waste and byproducts
with residual value can be directly
reused in other processes by another
manufacturer. In the past, these
materials may have been landfilled
or incinerated because it was less expensive
and there were few disposal
alternatives. Today, both environmental
and financial incentives encourage
materials reuse.
Beneficial reuse and recycling provide
additional revenue streams, or
at least the potential for cost reductions,
for the generator; however, they
add complexity to the removal-anddisposal
process. Rather than a oneway
transaction where the disposal
company removes and disposes of the
material, reuse and recycling may now
include waste removal discounts for
materials sold on the secondary market.
Tolling, where reprocessed materials
are returned to the generator,
also results in more complex price negotiations
based on fluctuating rates
for virgin materials.
Recycling, where the waste disposal
company reprocesses chemicals
for new uses, can also substantially
advance generators' sustainability
performance. The materials stay out
of the waste stream and become feedstock
for another company's process,
as outlined in Figure 1.
There are several other benefits
that accrue from the reuse and recycling
of chemical materials. In some
cases reuse and recycling operations
reclassify wastes, removing them from
the generator's hazardous waste manifest,
which reduces the volume of materials
listed in Toxics Release Inventory
(TRI) reports and advances waste
minimization goals. They contribute
to reduced taxes and annual fees associated
with RCRA regulations (see
box titled TRI Chemicals) and other
corporate responsibility and environmental
reports.
Clearly, sustainable disposal, reuse
and recycling require a more sophisticated
service level from the waste
disposal company. Only a few are able
to analyze the waste with an eye toward
potential uses and the secondary
market. They also have knowledge of
the underlying regulations and access
to the separation and purification resources
necessary to reprocess the materials
(see box titled Solvent Recycle
and Reuse). Companies that offer these
services along with in-house processing,
tolling and resale capabilities, are
best suited to develop comprehensive
waste management programs that
fully leverage sustainable secondary
uses for waste chemicals.
It makes financial and environmental
sense to explore these opportunities
with a waste processor.
■
Edited by Dorothy Lozowski
Author
Victor Belenchia is vice
president, chemical industry
for Clean Harbors (42
Longwater Dr., Norwell, MA
02061-9149; Email: belenchia.
victor@cleanharbors.com;
Phone: 781-792-5471; Website:
www.cleanharbors.com).
He holds a B.S. in biology and
chemistry from the University
of Central Connecticut and an
MBA in marketing from the
University of Connecticut. He spent more than
20 years in the chemical industry with American
Cyanamid and Cytec Industries in various
technical and commercial positions and has been
with Clean Harbors for the last six years in his
current role.
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Chemical Engineering December 2010

Table of Contents for the Digital Edition of Chemical Engineering December 2010
