Dry Cleaning Operations Case Study

Many dry cleaners are evaluating new cleaning processes as part of their overall environmental improvement program to help them reduce or eliminate the amount of hazardous waste generated and to save on hazardous waste disposal costs. Environmental improvement programs can also help generate more business by meeting your customer’s corporate or individual environmental goals. Businesses that implement environmental improvement projects are often viewed as valuable partners in the community.

In 1993, the Environmental Protection Agency issued national regulations in the form of a National Emission Standard for Hazardous Air Pollutant (NESHAP) that provides strategies to help perchloroethylene dry cleaning facilities lessen their impacts on the environment. EPA’s Plain English Guide for the Dry Cleaners provides detailed information on the NESHAP for perchloroethylene dry cleaning facilities.

EPA’s RCRA IN FOCUS provides an overview of the basic federal regulations covering wastes that are likely to be hazardous.

All cleaners, regardless of the technology they use, perform spotting before and/or after all major cleaning processes. The most widely used spotting agents are based on halogenated solvents including trichloroethylene (TCE), perchloroethylene, and a new solvent, npropyl bromide (nPB). These solvents can enter the sewer through wet cleaning processes and can contaminate the waste streams in solvent cleaning processes. The Institute for Research and Technical Assistance’s (IRTA) has prepared a fact sheet on commonly used spotting agents containing trichloroethylene (TCE) and perchloroethylene (PERC) and a report on alternative spotting agents.

Use the following table and links to additional resources to evaluate new cleaning processes such as liquid carbon dioxide, Green Earth, and green jet technology against the more traditional cleaning processes such as perchloroethylene, hydrocarbon, and wet cleaning. The table is arranged according to the most common use:

Process Equipment/Kauri-Butanol Value Benefits Concerns Environmental Impacts
Hydrocarbon
(includes Stoddard and 1400F petroleum solvents and DF-2000)

Comprises 70% of machines sold in the U.S. (DLI, 2010)

Two types: Dry-to-dry and transfer machines

Kauri-Butanol Value:

Stoddard: 29-45
DF-2000: 27
(SCRDC, 2010)

Good cleaning performance for a wide range of fabrics. Established technology. DF-2000 and 1400F are considered non-ignitable (EPA, 1998). Stoddard solvent is ranked by National Fire Association as ignitable (EPA, 1998). Hydrocarbon solvent wastes generated from certain cleaning processes are defined as hazardous waste. Considered a Volatile Organic Compound but not high in toxicity. May leak to ground water before reaching POTW. High risk of toxicity to aquatic species. Potential to contribute to smog and global warming (EPA, 1998).
Perc Dry Cleaning Comprises 20% of the machines sold in the U.S. (DLI, 2010) Two types: Dry-to-dry and transfer machines

Kauri-Butanol Value: 90
(SCRDC, 2010)

Aggressive solvent for oil-based contaminants (IRTA, 2008). Good cleaning performance for a wide range of fabrics. Established technology. Considered non-ignitable (EPA, 1998). Filters, sludge and still bottoms are disposed of as hazardous waste under RCRA. Classified as a Hazardous Air Pollutant under CAA. May leak to ground water before reaching POTW for treatment. Potential risk to aquatic organisms for effluent not treated by POTW (EPA, 1998).
Green Earth

Comprises 10% of the machines sold in the U.S. (DLI, 2010)

Cleans with liquid silicone.

Kauri-Butanol Value: 13

D5 not classified as a VOC. Higher flash point than hydrocarbon (IRTA, 2008). Cycle time longer than Perchloroethylene and Hydrocarbon (IRTA, 2008). Not managed as a hazardous waste (EPA, 1998).* Results from EPA study indicate potential cancer hazard (EPA, 2005). Identified as a potential concern to the environment (Government of Canada)
Hydrocarbon Dry Cleaning with Tonsil Uses the hydrocarbon
process with a material called tonsil, which is an absorbent. The absorbent is made of natural calcium bentonite material that is acid-activated (IRTA, 2009).
Controls bacterial growth by adsorbing moisture. No distillation so smaller in size than traditional hydrocarbon. No detergent needed. No transfer of dyes to other garments (IRTA, 2009). Still bottoms, will need to be removed and treated by a certified waste disposal service.
Traditional Wet Cleaning Relies on computer-controlled washers and dryers. Uses detergents, conditioners, and sizing agents. Some cleaners finish the garments with tensioning equipment (IRTA, 2008). Effective on both oil- based and water-soluble soils. Non-toxic, energy-efficient (IRTA, 2008). Cleaners must learn entirely new processing methods, garments may need to be hung which requires space, and the finishing may be more difficult and time consuming (IRTA, 2008). Not managed as a hazardous waste.* Potential risk to aquatic organisms from specific detergent component releases (EPA, 1998). Ranked as the best environmental option by IRTA.
Green Jet Technology Uses one machine to clean and dry the garments. The process uses a mist of water and detergent to clean the garments; garments are not immersed in liquid (IRTA, 2008).

Kauri-Butanol Value: Not available; process designed for garments that are lightly soiled.

Equipment is less expensive than the equipment used with solvents. Finishing is easier than with traditional wet cleaning since garments are not immersed. No tensioning equipment required (IRTA, 2008). Process designed only for garments that are lightly soiled. Should only be used as a supplementary technology (IRTA, 2008). Not managed as a hazardous waste (IRTA, 2008).*
Carbon Dioxide Technology Relies on liquid carbon dioxide under pressure, filters for removing particulate contaminants and a distillation unit for separating the soluble contaminants. Does not use heat (IRTA, 2008). Many oil-based contaminants are soluble in carbon dioxide (IRTA, 2008). More spotting is required with carbon dioxide than with PERC. The detergent used in the carbon dioxide process is relatively expensive. Vinyl, rubber or beads can swell during the cleaning process. Some acetate and Triacetate materials cannot be cleaned with carbon dioxide (IRTA, 2008). Not managed as a hazardous waste (EPA, 1998).* Ranked as the best environmental option by IRTA. Closed-loop machine reduces CO2 emissions by recovering/recycling solvent (EPA, 1998).

* Keep in mind that spotting agents or other contaminants on clothing can contaminate the waste streams of a cleaning process. To identify whether your waste stream is hazardous, send a representative sample to a certified laboratory for analysis.

References

  • USEPA. 1998. Cleaner Technologies Substitutes Assessment: Professional Fabricare Processes. EPA 744-B-98-001. USEPA, Office of Pollution Prevention and Toxics. Washington, DC. June.
  • IRTA. 2008. Institute for Research and Technical Assistance. AB998 Non-Toxic Dry Cleaning Incentive Program: Demonstrations of Safer Technologies for the Textile Cleaning Industry. Prepared for California Air Resources Board and the California Environmental Protection Agency Under Grant Number DP07-0001. May.
  • IRTA. 2008. Institute for Research and Technical Assistance. Presentation: Alternative Textile Cleaning Processes and Spotting Chemicals: Will They Really Be Safer?
  • USEPA. 2005. Siloxane D5 in Drycleaning Applications. Office of Pollution Prevention and Toxics. 774-F-03-004. December.
  • DLI. 2010. Drycleaning & Laundry Institute. www.ifi.org
  • SCRDC. 2010. State Coalition for Remediation of Dry Cleaners.

Resource Links

Questions?

Eleanor Divver, Business Assistance Coordinator: (801) 536-0091