I thought you might be interested in this message, which I am
forwarding from the P2Tech listserv.
------- Forwarded Message Follows -------
Ron Joseph asks:
Does anyone know what really does happen to the solvent-laden rags
when they arrive at the laundries? I can't see any P2 opportunity
here, except for specifying the use of rags that can be recycled more
frequently. In fact, I have heard of one air force base that does
have a specification for the rags they purchase. Can anyone throw new
light on this?
I don't know the details of the air force base and the rag specs you
mentioned. But based on the P2 assessments conducted for EPA Region 9 at five
industrial laundries in Southern Californian 1992-93, I can offer to send you a
report on what "really does happen to the solvent-laden rags when they arrive
at the laundries" - at least for these S. California facilities.
The report by Bob Kerr and Cam Metcalf identified several reuse & P2 opportunities along the
way -the most important being steps the customer can take to reduce
hazardous solvent use and some basic best management practices that
laundries can adopt for shop towels.
When laundry route salespeople pick up shop towels from customers,
ideally they ensure that shop towels are not accepted bearing free
liquid. Once shop towels arrive at the laundry, they are ordinarily sorted
according to soil/solvent type. Laundries varied in techniques for handling rags.
Prior to water washing, some of these laundries utilized one of two
methods for recovering solvents from the soiled rags: 1) centrifuging
and 2) VOC stripping. One laundry utilized a VOC stripper that processes
the soiled shop towels by injecting live steam at controlled temperatures
to release the solvents from the fabric. The steam and VOC vapors are drawn off
through a condenser to a separator where the VOCS are recovered. A
cold water rinse cycle quickly lowers the temperature of the shop towels for unloading. The
recovered solvents are stored in tanks and ideally, a laundry might investigate
the option of returning recovered VOCs to the customer/generator for reuse at their
facility possibly prompting a P2 analysis at the facility itself.
Sometimes heavily soiled shop towels are soaked overnight. When shop
towels are laundered, temperatures of 165-170 degrees F or a terpene
cleaner are sometimes used to remove heavy, oily soils. At another
plant, sulfuric acid cracking (pH2-3) is used to break or float the
oil/soils from the towels. For more details, I can send you the
report with flow charts.
The most promising P2 opportunity for reducing waste from shop towels
rests with the customer - hopefully, the customer undertakes an
analysis of the solvents used. EPA's Design for the Environment
program produced a fact sheet under the PrintingProject (Case Study 1)
about a P2 program at the John Roberts Company (printer) in
Minneapolis. The industrial laundry picking up the company's towels
was facing problems from a local regulatory agency causing the
laundry's effluent to exceed the lower explosive limit (LEL). Instead
of using type wash solvent frequently, the company reserved its use forvery specific cases and switched to a
replacement solvent with a lower evaporation rate (and they saved $18,000 in the
first year by doing so).
Since the time of the 92-93 EPA Region 9 Industrial Laundry Study,
the Region has initiated a follow-up industrial laundry study, this
time focused on the key question of customer outreach. The study is
currently underway with a Southern California industrial laundry comparing different approaches of
working with customers to reduce the waste generated and contaminating uniforms and
shop towels. For more information, contact Bonnie Barkett of the
Water Management Division, EPA Region 9 at (415) 744-1908.
If you're interested in the 1992-93 study or the DfE fact sheet, let
EPA Region 9
75 Hawthorne Street, H-W-2
San Francisco, CA 94105
Fax (415) 744-1796