United States
Environmental Protection
Agency
National Risk Management
Research Laboratory
Research Triangle Park NC 27711
Research and Development
EPA/600/SR-96/030 April 1996
4>EPA Project Summary
Review of Control Options for
Methyl Bromide in Commodity
Treatment
Glenn B. DeWolf and Jim L. Phillips
Methyl bromide (MeBr), a fumigant
for agricultural commodities, is an
ozone depleting chemical. The U.S. EPA
has banned its use beginning in 2001.
In some applications, a suitable substi-
tute for MeBr has not been found, so
there is discussion of an exempted use
of MeBr with capture and recovery or
recycle for some applications. The re-
port describes recent developments in
control of MeBr and discusses techni-
cal considerations and requirements for
and economic feasibility of recovery.
The primary focus of the report is on
quarantine applications using MeBr.
Two of the most promising approaches
to recovery, recycle, and reuse con-
tinue to be physical adsorption on a
solid sorbent and cryogenic condensa-
tion. In addition to discussing each of
these technologies, the report identi-
fies some of the critical considerations
for process economics and remaining
information gaps. The overall conclu-
sion of this review is that recovery,
recycle, and reuse appear to be fea-
sible, have not been unequivocally
proven to be so, and there is little cur-
rent incentive to pursue such technolo-
gies unless there is hope of exemptions
to or a recision of the MeBr ban.
This Project Summary was developed
by EPA's National Risk Management
Research Laboratory, Research Triangle
Park, NC, to announce key findings of
the research project that is fully docu-
mented in a separate report of the same
title (see Project Report ordering infor-
mation at back).
Overview
Methyl bromide (MeBr), a significant fu-
migant for agricultural commodities, is
listed by the Montreal Protocol as an ozone
depleting chemical. The U.S. EPA has
banned its use beginning in 2001. In some
applications, a suitable substitute for MeBr
has not been found, so there is discus-
sion of an exempted use of MeBr with
capture and recovery or recycle for some
applications. In 1994, a brief study was
undertaken to characterize fumigation pro-
cesses for one important type of com-
modity fumigation, space fumigation, and
to identify potential methods for control,
recovery, and recycle of MeBr. EPA is-
sued a report in 1994. Since that time,
there have been additional developments
in finding appropriate technologies for this
purpose. Continuing interest in the sub-
ject has been reflected in two prominent
forums for disseminating information re-
lated to MeBr. The first was a conference
held in Orlando, Florida, in November
1994. The second was a report issued by
the United Nations Methyl Bromide Tech-
nical Options Committee in 1995. Also an
important development was the installa-
tion and testing of a MeBr treatment and
reuse system at the Port of San Diego in
1995. Because of these advances, and
additional study, this report was prepared
to communicate information on these de-
velopments and to discuss further techni-
cal considerations and requirements for
technical and economic feasibility of re-
covery. The primary focus of this report is
on MeBr treatment in quarantine applica-
tions.
-------
At this time, two of the most promising
approaches to recovery, recycle, and re-
use continue to be physical adsorption on
a solid sorbent and cryogenic condensa-
tion.
A new adsorption system was installed
and tested at the Port of San Diego. Based
on zeolite adsorption technology, the sys-
tem achieved over 95% removal efficiency
of MeBr from the post-fumigation vent
stream. This is consistent with expecta-
tions based on other tests that have been
reported. In addition to zeolite adsorption,
condensation at cryogenic temperatures
still appears to be a potentially feasible
candidate for some applications. However,
like activated carbon, another candidate
technology, little if any new activity in these
areas appears to have occurred recently.
In addition to discussions on each of these
technologies and their costs, this report
identifies some of the critical consider-
ations for process economics and identi-
fies remaining information gaps and further
needs. The overall conclusion of this re-
view is that recovery, recycle, and reuse
appear to be feasible, have not been un-
equivocally proven to be so, and there is
little current incentive to pursue such tech-
nologies unless there is hope of exemp-
tions to or a recision of the MeBr ban.
Glenn B. DeWolfandJim L. Phillips are with Radian Corp., Austin TX 78720-1088.
Robert V. Hendriks is the EPA Project Officer (see below).
The complete report, entitled "Review of Control Options for Methyl Bromide in
Commodity Treatment," (Order No. PB96-167556 Cost: $21.50, subject to
change) will be available only from
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at
National Risk Management Research Laboratory
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
United States
Environmental Protection Agency
National Risk Management
Research Laboratory (G-72)
Cincinnati, OH 45268
BULK RATE
POSTAGE & FEES PAID
EPA
PERMIT No. G-35
Official Business
Penalty for Private Use
$300
EPA/600/SR-96/030
------- |