Pollution Prevention for Dry-cleaners. Published by Metro-Dade County

Pollution Prevention for Dry-cleaners

Published by:

Metro-Dade County
Department of Environmental Resources Management
33 S.W. 2nd Avenue
Miami, FL 33130-1540

Last Revision:  August 1995

This document is published to help educate businesses on some of the environmental issues affecting them. It suggests options that may help businesses to operate in an environmentally appropriate manner. They are based on experience and simple common sense ideas. Many of the options go beyond what is required to remain in compliance with the regulations. Please refer to Chapter 24 of the Metropolitan Dade County Code ("Metropolitan Dade County Environmental Protection Ordinance") for the specific regulations.

What is pollution prevention?

It is the reduction or elimination of pollutants or wastes at the source. The idea behind pollution prevention is to avoid producing the waste in the first place. If the waste is not produced, then you don't have to worry about storage or disposal problems. Having less waste means a better environment for all of us.

What's in it for you?

Dry-cleaners deal with many hazardous chemicals. Hey, it's part of the business! But, you can reduce the amount of waste your shop produces by following some simple pollution prevention tips. Look at some of the benefits:

* Save money! * Protect workers, the public, and the environment! * Improve your company image! * Reduce the risk of liability!

What can you do?

Dade County D.E.R.M. (Department of Environmental Resources Management) is encouraging every business to reduce pollution by starting a waste reduction program. Here are some things to consider when setting up your program.

* Make a commitment to pollution prevention. This commitment should start at the top, with the owner or manager of your shop. It should be made a part of your company's policy.

* Employee participation. Every employee must be aware of the importance of waste reduction through pollution prevention practices. Their participation and suggestions in your waste reduction program will help to make it a success.

* Evaluate your shop's waste. Look around your shop to see how much and what kind of waste is being produced. This will make it easier for you to spot areas where pollution prevention tips can be applied.

* Find some new ideas. Talk to other employees, or vendors, or even inspectors. Maybe they can help you. Or look through trade journals or magazines. There is always a better way to do things.

* Make the change! Don't be afraid to experiment.

Many pollution prevention practices are low-cost and low-risk alternatives to help minimize waste and the resulting disposal costs. Most of the approaches are based on common sense and do not require sophisticated technology. This booklet contains some ideas to get you started. Your shop may already be using pollution prevention practices without realizing it!

Keep it clean!

Poor housekeeping results in spills and overflows. This may double your expense by making you pay to replace lost material and also for its treatment and disposal. It can also lead to accidents and worker injury. Good housekeeping is one of the easiest and least expensive way to reduce waste. Here are some tips:

* Keep your shop clean and your floors dry. Sweep floors and use dry or damp clean-up techniques. For example, use absorbent material for spills and if necessary, use a very small volume of water for final cleanup. This material should then be disposed of properly.

* Practice good inventory control. Mark the purchase date on containers and adopt a "first in, first out" policy, so that older materials are used up before new ones are bought.

* Keep all containers closed and properly labeled.

* Keep storage and work areas clean and well organized.

* Do not mix hazardous chemicals with non-hazardous chemicals. Otherwise all of the waste will have to be treated as a hazardous waste. This can be very expensive.

Dry-cleaners use many different chemicals, machines, and processes. Often things are done a certain way simply because, "It's always been done that way." Remember, there is always room for improvement and, "An ounce of (pollution) prevention is better than a pound of cure."

Dry Cleaning Chemicals

Typically one of three types of cleaning solvents is used:

* Perchloroethylene (PCE or simply "perc") This is the most commonly used dry-cleaning solvent.

* Petroleum solvents (e.g. Stoddard, quick-dry, or low-odor). Many new non-chlorinated petroleum solvents are being formulated that are not flammable (Flashpoint > 140 deg F). Wastes from the use of these substances may be hazardous, but their air emissions are not regulated as closely as perc.

* Fluorocarbon 113 or Trichlorotrifluoroethane (Valclene[tm]) Title Vl of the Clean Air Act Amendments of 1990 has mandated the phaseout of the production of certain Ozone Depleting Substances. This includes Fluorocarbon 113, which will not be manufactured after January 1, 1996. Multi-Process Wet Cleaning is a new approach that uses the controlled application of heat, steam and natural soaps to clean clothes that are typically dry-cleaned. Garments are not necessarily saturated with water and are not damaged. Contact the Pollution Prevention Program for more information.

Dry-cleaners & the "Perc" M.A.C.T. Standards

Title III of the Clean Air Act Amendments of 1990 lists perchloroethylene as one of the 189 chemicals to be regulated as Hazardous Air Pollutants (HAPs). Facilities using these chemicals will be required to lower their air emission levels to those established in Maximum Achievable Control Technology (M.A.C.T.) standards. The M.A.C.T. standards for dry-cleaners using perchloroethylene have already been established and are summarized in the Table (see Pg.7-8). Vapor emissions from dry-cleaners can be classified into two general types: 1) Process Vent and 2) Fugitive.

1) Reducing Process Vent Emissions:

In a VENTED process, during the aeration cycle, fresh air is introduced and passed through the clothes. The air that is subsequently vented can contain significant quantities of solvent. Here are some tips to reduce process vent emissions:

* Use a non-vented dry-to-dry machine.

* Pass process vent emissions through a refrigerated condenser and/or carbon adsorber.

(Ref. Pg. 7-8 for specific source category requirements.)

Refrigerated Condensers

Refrigerated condensers recover solvent vapor emissions by cooling the air stream to a temperature below the solvent's dew point. This causes the solvent (and usually water vapor) to condense into a liquid form.

* Refrigerated condensers can be used in the following areas:

-- On the air stream at the end of the drying cycle.
-- On the air stream at the final exhaust point for the process.
-- On the air stream received from the washer in transfer type machines.
-- On the vapors from the dryer during the drying cycle. This air stream is continually passed through the condenser and back to the dryer.

* It is important to maintain the proper condensing coil-in and coil-out temperatures. Generally the exhaust on the outlet side of a refrigerated condenser should be equal to or less than 45 deg F (7 deg C). As well, a temperature difference of at least 20 deg F (11 deg C) between inlet and exhaust may be recommended.

* Regular measurement and recording of the exhaust (and inlet) temperatures may be required. (Ref. Pg. 7-8 for specific source category requirements.)

Carbon Adsorbers

Carbon adsorbers remove vapors from an air stream by absorbing the vapor onto the surfaces of a bed of activated carbon.

* Carbon adsorption (sniffer) units can:

-- Handle high air flows with low solvent concentrations.
-- Reduce solvent vapors in exhaust by up to 95%.
-- Range in size from 100 to 1,000 lb.


* Carbon adsorption (sniffer) units can be used in the following areas:

-- As a secondary add-on control, after refrigerated condensers. These units are used to "clean" the air even further and capture low concentrations of solvents.
-- As a control for fugitive emissions.

* To optimize performance of the carbon adsorber units:

-- Determine and maintain the maximum or optimum ratio of clothes cleaned for the quantity of activated carbon used.
-- Maintain the optimum solvent to carbon ratio to ensure that the stripping is done at proper intervals according to equipment manufacturer instructions.
-- Determine and maintain the optimum air flow rate passed through the carbon bed.
-- Determine and maintain the optimum steam pressure used to strip solvents from the carbon bed. This steam and solvent mixture can then be separated and the solvent distilled for reuse.
* Regular measurement of the concentration of perchloroethylene in the exhaust from the carbon adsorbers may be required. This can be performed using a colorimetric tube when the adsorber is operating at the finish of a dry cleaning cycle. (Ref. Pg. 7-8 for specific source category requirements.)

* Carbon adsorber exhaust concentrations should generally be less than 100 ppm. For no-vent type carbon adsorbers the perc concentration inside the dry cleaning drum at the finish of the cycle should be less than 300 ppm.

2) Reducing Fugitive Emissions:
Fugitive emissions can be attributed to a variety of sources including clothing transfer from washer to dryer for transfer type machines, equipment leaks, open containers, opening of the equipment doors, etc. Here are some tips to help you to reduce fugitive emissions:
* Replace transfer machines with dry-to-dry machines. For transfer machines, the tumblers or reclaimers may not be replaced. Any machine replacements must be with dry-to-dry machines. Any new sources must use dry-to-dry machines.

* Room enclosures

A room enclosure is a stationary structure enclosing transfer type dry cleaning machines. Air in this room enclosure can then be vented to a carbon adsorber or similar control device. (Ref. Pg. 7-8 for specific source category requirements.)

The following sections discuss reducing fugitive vapor emissions from equipment leaks, distillation operations, filter muck, and cartridge filters.

Equipment Leaks

Equipment leaks can account for up to 25% of the solvent emissions from dry cleaning operations.

* Leaks can be detected by:

-- The odor of perchloroethylene.

-- Visual observations, such as dripping or puddles of liquid.

-- The detection of a gas flow by passing fingers over the equipment.

-- The use of a halogenated-hydrocarbon detector. This is usually the most accurate, reliable, and quickest method.

* Places to check for leaks include: hose and pipe connections, fittings, couplings, and valves; door gasket seating; filter gaskets and seating; pumps; solvent tanks and containers; water separators; "muck cookers"; distillation units; exhaust dampers; diverter valves; and cartridge filter housings.

TABLE [refer to source document] SUMMARY OF REQUIREMENTS OF THE PERCHLOROETHYLENE (PCE) DRY-CLEANING National Emission Standard for Hazardous Air Pollutants (NESHAP)

Machine Types at Facility; PCE Consumption per year

Only Dry-to-Dry; < 140 gallons; < 200 gallons; < 140 gallons Only Transfer; 140-2,100 gallons; 200-1,800 gallons; 140-1,800 gallons Both Dry-to-Dry and Transfer; > 2,100 gallons; > 1,800 gallons; >1,800 gallons

Then you are classified as a; SMALL AREA Source; LARGE AREA Source; MAJOR Source

Process Vent Controls

at Existing Facilities; -None; Refrigerated condenser or equivalent., Existing carbon adsorbers can remain. at New Facilities (after Dec. 9,1991); -Refrigerated condenser or

equivalent.; -Refrigerated condenser followed by small carbon adsorber or equivalent. Fugitive Controls

at Existing Facilities; -Leak detection and repair., -Store all PCE solvent & waste in sealed containers.; -Room enclosure

at New Facilities (after Dec. 9, 1991); -Leak detection and repair.; -Store all PCE solvent and waste in sealed containers.; -No new transfer type machines allowed.

Monitoring

at Existing Facilities; -None

at New Facilities (after Dec. 9, 1991); -Same as for "Large Area" and "Major" sources. -Refrigerated condenser (RC): Measure the temperature at the end

of the cycle on the outlet side of the RC on a dry-to-dry machine, dryer, or reclaimer. (Needs to be < or = 45 deg F.) Measure the inlet and outlet temperature difference of the RC on a washer. (Needs to be >or= 20 deg F)

-Carbon adsorber (CA): Measure the PCE concentration out of the CA (used for process vent control) with a colorimetric detector tube. (Must be < or = 100 ppm.)

Operation/Maintenance

at New & Existing Facilities; -Operate and maintain dry cleaning systems according to manufacturer's specifications and recommendations.

at New & Existing Facilities; -Each facility must maintain monthly records of PCE purchases, calculations and results of yearly PCE consumption based on PCE purchase receipts and dated records of all monitoring data and pollution prevention activities These must be retained for at least 5 years.

Reporting

at New & Existing Facilities; -Each facility must submit an initial report and a compliance report. Reports must be certified by a responsible official.

For a complete listing and explanation of the requirements for each of the source categories please contact the Air Section (305) 372-6925.

[end of table] * Documentation of regular leak inspections is required.

* If fugitive equipment leaks are detected:

-- Begin the process of repair within 24 hours.

-- If you need parts they should be ordered within 2 days.

-- Install parts within five days of receipt .

-- Actions taken to repair identified leaks should be documented.

Distillation

On-site distillation is the primary method used in purifying and recovering the dry cleaning solvent for reuse. Distillation residues, or still bottoms, may still contain as much as 50% solvent in addition to any non-volatile components, such as dirt, detergents, waxes, oils, greases, etc.

* These still bottoms are a RCRA hazardous waste end must be handled and disposed of properly.

* Regularly remove the residues in distillation units to improve their efficiency.

* The addition of steam (water) can enhance distillation, but will also increase the volume of wastewater. The mixture of water with distillation residues can form a perc/water azeotrope that boils at a lower temperature than pure perchloroethylene. As a result, the distillation rate increases and perc separates more completely from the nonvolatile components.

* To recover more solvent or reduce solvent content in the residue after a first boil-down, add water and redistill the residue. However, this can also increase the volume of wastewater. (Refer to "Wastewater & Perchloroethylene" on Pg. 11 )

* Vents from distillation units can be ducted directly to refrigerated condensers and carbon adsorber beds to minimize vapor emissions, if economically possible.

Cartridge Filters

Cartridge filters with carbon-cores are the most common type of filter used in dry cleaning.

* Spent cartridge filters are a RCRA hazardous waste and must be handled and disposed of properly.

* Cartridges should be drained for at least 24 hours in a closed container. These cartridges can contain as much as 1 gallon of solvent.

* Filters can be dried in enclosures that are vented to a refrigerated condenser and/or carbon adsorbers.

* Steam can be used to strip and recover additional solvent from the cartridge. This solvent and water mixture can then be separated and the solvent reclaimed in a distillation unit.

* Determine and maintain the optimal amount of clothes cleaned per standard cartridge before replacement or stripping is necessary.

* Determine and use the optimal steam pressure for stripping cartridges.

* Hot air that is vented to a refrigerated condenser and/or carbon adsorber bed can be used for stripping cartridges.

This can help to reduce wastewater if steam is normally used to strip cartridges.

Filter Muck

When dirty solvent is passed through a filter it creates a reusable solvent and filter "muck".

* Filter muck is a RCRA hazardous waste and must be handled and disposed of properly.

* A "muck cooker" can be used to heat the muck material and evaporate any solvent. These vapor emissions are then collected, cooled, condensed and reclaimed for reuse. Any residue must be disposed of properly as a hazardous waste.

Wastewater Perchloroethylene

Even though water will float on top of perchloroethylene, the perc is slightly soluble in water (up to 150 ppm or 0.015%) at standard conditions. The water can be drained off of the top and treated, and the perchloroethylene on the bottom can be collected for reuse.

* Wastewater containing perchloroethylene can come from:

-- Water separators used in condensers, carbon adsorbers, cartridge strippers, stills, and muck cookers.

-- Wash water from the laundering of industrial rags or garments.

-- Wash water from laundering with certain spot and stain treatment chemicals.

* Wastewaters containing perchloroethylene can be passed through carbon filters to reduce perchloroethylene levels prior to discharge to sanitary sewers. In Dade County the sanitary sewer discharge concentration limit for perchloroethylene is 2 ppm. Contact the Wastewater Section with any questions.

Solid Waste Reduction

Dry cleaners can help to reduce solid waste by working with their customers. They can do this by establishing a system and encouraging their customers to:

* Purchase and use heavy duty reusable garment bags when picking up dry cleaning instead of the standard light weight plastic garment covers.

* Bring back hangers to the dry cleaners for reuse.

BOILERS

Boilers are often used to generate steam for a variety of applications by dry cleaners.

* No boiler "blowdown" should be discharged to. the ground. Any boiler "blowdown" should be disposed of to sanitary sewers or by another approved method. Contact the Wastewater Section for the sanitary sewer standards.

* All boiler fuel tanks are required to have secondary containment to prevent accidental discharge of fuel to the floor or ground. Contact the Hazardous Facilities Section about requirements for secondary containment.

What if you have an accidental spill?

Here are some first steps if you have an accidental spill:

* Identify what has caused the leak or spill.

* Take steps to stop and contain any leaks. Follow any required repair and documentation procedures. (Refer to "Equipment Leaks" on Pg. 6)

* Immediately begin clean-up procedures. Any absorbent materials which are used to clean up the spill must be disposed of properly as a hazardous waste.

* Notify the appropriate D.E.R.M. Section (Hazardous Waste, Wastewater) and begin clean-up procedures. Florida requires that a discharge of 1 quart or more of dry cleaning solvent be reported to the State Warning Point (904)413-9911.

* Take steps to prevent this from occurring in the future.

The State of Florida has legislation in the form of a Dry-cleaning Contamination Cleanup Bill that establishes a program to assist dry-cleaners in the restoration of potable water supplies that have been contaminated by perchloroethylene. Dry-cleaners that participate are required to register and contribute to the fund each year. In the event of a spill the fund will act as an "insurance policy" and assist in paying a percentage of the clean-up costs, if the site meets certain eligibility requirements. For more information, please contact the Bureau of Waste Cleanup, State of Florida Department of Environmental Protection Ph: (904) 488-019 or S.E. District Office Ph: (407) 433-2650.

Hazardous materials storage

Below are some suggestions for storage of hazardous materials:

* Store on an impervious (sealed) surface, i.e. resists infiltration or corrosion by the stored materials.

* Store under cover,whether indoors or outdoors, to keep out the rain. Check with the Fire Department.

* Provide some type of secondary containment hat will hold up to 110% of the largest container stored in the area. This area should be able to catch and contain any leaks or spills.

* Label waste containers properly, including contents and date of generation for any hazardous wastes.

* Make sure drums are easily accessible but not stored in high traffic areas where they can be easily knocked over.

* Be sure containers are properly sealed. Regularly check for any signs of leak, rust, etc.

What to do with hazardous waste?

* Keep all records of Hazardous Waste handled on site for at least three (3) years. This includes amounts purchased, stored, reused, and hauled away.

* Hazardous waste should be shipped out by an properly permitted hauler to an EPA approved treatment, storage, and disposal facility. Check for all the proper local, state, and federal licenses. Contact D.E.R.M. for a list of approved haulers.

* The facility generating the waste should obtain an EPA identification number from the address below, unless officially classified as a "Conditionally Exempt Small Quantity Generator."

Bureau of Waste Planning and Regulation Twin Towers Office Bldg 2600 Blair Stone Road Tallahassee, FL 32399-2400 Ph: (904)487-3299

Phone Numbers

METRO-DADE COUNTY

Dept. of Environmental Resources Management

Main Switchboard (305) 372-6789
Wastewater Section (305) 372-6500
Air Section (305) 372-6925
Hazardous Facilities Section (305) 372-6600
Liquid Waste Transporters (305) 372-6804
Hazardous Waste Section (305) 372-6804


FLORIDA DEPT. OF ENVIRONMENTAL PROTECTION

Southeast Region Office (407) 433-2650
Tallahassee Office (904) 488-0300
State Warning Point (407) 433-2650
For more information ask for "Florida's Handbook for Small Quantity Generators of Hazardous Waste"
Sources of Additional Help For Pollution Prevention
Metro-Dade County
Department of Environmental Resources Management
Pollution Prevention (P2) Program (305)372-6789. The P2 program publishes a quarterly newsletter, has a library of information, holds workshops and training periodically, and provides on-site consultation to select facilities.

Florida Department of Environmental Protection

Pollution Prevention Program (904)488-0300. This program provides technical assistance in the form of informational resources, research for waste reduction options, telephone consultation, experts and speakers for workshops, and on-site waste reduction assessments to business, industry, and governmental agencies in Florida.

The Florida Clean Air Act

Small Business Assistance Program

1-800-722-7457. This office assists small businesses with compliance under the new Clean Air Act Amendments.

Waste Reduction Resource Center

1-800-476-8686. The center provides information to persons in EPA's Region IV (Florida included). Their library contains over 3000 journal articles, case studies, technical assistance reports and books.

DERM
Department of Environmental Resource Management
Office of Sustainable Environment & Education
Pollution Prevention Program
33 S.W. 2nd Avenue
Miami, Florida 33130-1540

This document was printed on recycled paper with at least 10% post-consumer content


Return to the top of this document.

Last Updated: April 23, 1997