Bulletin 3 - Work Practice Alternatives for Screen Reclamation

Increase the Benefits
by Reducing Your
Chemical Use

The Design for the Environment (DfE) Screen Printing Partnership is a voluntary cooperative effort between the screen printing industry and the U.S. Environmental Protection Agency (EPA) dedicated to helping screen printers improve their efforts to reduce risk to their workers and the environment in cost effective ways.

Printers, EPA, product manufacturers, and the screen printing trade association are all concerned with minimizing the environmental and health hazards of screen reclamation. Through the DfE Screen Printing Partnership, these groups are working together to ide ntify and share information on alternative screen reclamation work practices and to evaluate alternative screen reclamation products. Using information from a survey of screen printers, DfE identified many alternative workplace practices that participants found helped them prevent pollution while reducing chemical exposures and screen cleaning costs.

This bulletin describes simple changes in screen reclamation work practices that have resulted in significant reductions in costs, environmental impact and worker exposures. Although this bulletin concentrates on preventing pollution in the screen reclama tion process, it highlights a basic framework for pollution prevention through improved work practices that can be applied to any process in your shop.

Background

A survey of screen printers (conducted by the screen printing trade association) determined that almost 36 percent of the respondents had implemented changes in workplace practices to reduce their use of ink removal or screen cleaning/reclamation products. With little or no capital expenditures, pollution prevention through improved workplace practices can result in cost savings through the reduced use of materials, lower waste disposal costs, less worker exposure and other benefits. Improving work practices to prevent pollution is simply a common-sense approach to running a print shop.

The first step in a pollution prevention program is to examine your process and identify the waste generated by each process step, any inefficient use of resources, and areas where improvements can be made. This examination can be accomplished through an in-house process evaluation. Undertaking a process evaluation involves observing, measuring, and recording data on the materials used and waste generated in your shop. This information will then allow you to take a comprehensive look at your facility and to focus your attention on areas where waste reduction and cost savings are most easily accomplished. After your initial evaluation, periodic in-house evaluations will help you determine the effectiveness of alternative products and practices being implemented. The process evaluation results should be shared with all employees to raise employee awareness about the benefits of the pollution prevention program, to provide them with feedback on pollution prevention progress, and to get their input on improvements. In-house evaluations can give both operators and managers the incentive to strive for continuous improvement.

How Everyone Can Help

Process Improvements

After obtaining a good understanding of your material flows and waste streams through a process evaluation, you should identify your opportunities for pollution prevention. While the materials use and waste generation are different in every shop, and solutions particular to your operation may need to be developed, many of the printers contacted through the survey found similar pollution prevention solutions to be effective, including:

Keep chemicals in safety cans or covered containers.
This minimizes chemical losses from evaporation and spills.

Use plunger cans, squeeze bottles, or specialized spraying equipment to apply chemicals.
The use of such equipment can reduce materials and accidental spills.

Use manual spot application of screen reclamation chemicals and alternative rinses.
One printer reduced chemicals use for screen cleaning 15% by using spot application of ink degradant, and a low pressure rinse, followed by a high pressure water blast.

Reuse shop towels to reduce ink remover use.
If using towels for ink removal, reuse the towel from the last pass of one screen for the first pass on the next screen. This will reduce the number of towels disposed of or sent to the laundry service.

Try increasing your water dilution.
Some printers have been able to dilute their screen reclamation products without reducing performance.

Avoid delays in cleaning and reclaiming screens.
If screens are cleaned promptly, the chemicals needed to remove ink, emulsion, and haze can be reduced.

Recover solvent from rags for reuse.
Some printers realized significant savings in their chemical costs by recovering solvent from used rags either by gravity draining, wringing the solvent into a covered container, or using an explosion-proof centrifuge.

Recover used cleaning product and chemical overspray for reuse.
One printer found that used cleaning chemicals could be captured, treated in a small still to remove pigments, and then used again. Another printer found that installing a simple "catching frame" around each screen to capture overspray during chemical application steps allowed significant amount of chemical to be reused.

Reuse Your Reclamation
Chemicals

Many printers have found that proper materials management and inventory control cut both the amount of chemicals used and their screen cleaning costs. Keeping track of chemical usage clarifies materials flow, how it relates to waste generation rates, and where pollution prevention opportunities can be implemented. Materials management and inventory control techniques used by many printers to help reduce material use and disposal include:

Manage inventories on a first-in, first-out basis.
This will minimize the disposal of expired materials.

Maintain accurate logs of your chemical and materials stock, use and waste generation rates.
This will help you evaluate your shop's materials flow and identify where wastes are being generated.

Minimize the amount of chemicals in the production area.
This will encourage materials conservation.

Keep all wastes separate and in clearly marked containers.
This allows wastes to be reused or recycled, and prevents hazardous wastes from contaminating non-hazardous wastes.

Keeping it Going

According to many printers, a reluctance to change to alternative screen cleaning products or work practices is one of the largest obstacles to pollution prevention in their shops. Much of this unwillingness to try new products, technologies, and procedures arises from employees' lack of awareness of the benefits and a belief that the alternatives will not work. Training on health and safety issues and on materials handling and disposal procedures will help employees understand both the benefits of proper materials handling and disposal and the potential consequences of improper workplace practices to their health and safety, the environment, and company profitability.

Seek your employees' input on pollution prevention activities to encourage their participation; the people closest to the process often come up with the most creative approaches to pollution prevention. Awareness of materials use and waste generati on can be fostered by centralizing the responsibility for storing and distributing chemicals, by making employees accountable for the waste they generate, and by providing incentives for waste reductions.

It is important that employees are aware of your company's commitment to environmental goals and pollution prevention. Depending on the company size, it may be helpful to prepare a written environmental policy and written procedures on proper equipment operation, maintenance, and materials handling and disposal. Providing feedback to employees on materials handling, disposal and pollution prevention performance re-emphasizes your commitment to pollution prevention and encourages your employees to continue to improve their workplace practices.

Finally, pollution prevention should be an ongoing process where work practices are monitored regularly to ensure that improved practices already identified are actually being implemented on the shop floor, and that new opportunities for pollution prevent ion are being identified continuously.

Reduce Your
Chemical Use
Through Continuous Improvement

For more detailed information on technological and chemical alternatives for screen reclamation, see the DfE Screen Printing Partnership summary booklet, Designing Solutions for Screen Printers: An Evaluation of Screen Reclamation Systems. Additional case studies and other bulletins summarizing the evaluation of screen reclamation alternatives are also available.

For copies of this bulletin, other DfE Screen Printing Partnership materials, or for more information about the project, please contact:

Pollution Prevention Information Clearinghouse (PPIC)
U.S. Environmental Protection Agency
1200 Pennsylvania Ave. NW (7407-T)
Washington, DC 20460-0001
Phone: 202-566-0799
FAX: 202-566-0794
Email: ppic@epamail.epa.gov

or

Screenprinting and Graphic Imaging Association International (SGIA)
10015 Main Street
Fairfax, VA 22031
Telephone: (703) 385-1335
Fax: (703) 273-2870