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Pollution Prevention
Photographic Processing Fact
Sheet
Office of Pollution
Prevention |
P2 in photographic processing
The photographic processing industry includes a large number of diverse
establishments processing a wide range of films and papers. The primary waste
streams associated with this industry are process bath wastes, color developer
wastes, bleach, fixer and bleach-fixer wastes. Substances of particular
environmental concern often found in photofinishing effluents include silver,
cadmium, chromium and ferrocyanide.
Reduction of these wastes, and others, involves improved housekeeping
practices, process modifications, and recovery and reuse.
Various pollution prevention practices for the photographic processing
industry are summarized in the following lists:
Improved
housekeeping
- Compare process inputs with outputs to identify
quantity of materials discharged in water.
- Stop water flow when film processing is halted.
- Directly pump bulk chemicals to lower risk of
spillage.
- Dedicate pumps to certain chemicals to reduce
cleaning operation wastes.
- Accurately add and monitor chemical replenishment
of process baths.
- Pay careful attention to storage specifications of
photosensitive film and
paper.
Process
modifications
- Use squeegees to wipe excess liquid from the
moving photographic material; to reduce contamination of process baths.
- Redesign tanks to convert an existing wash system
to a counter-current system in order to reduce water use and costs.
- Substitute less environmentally harmful
iron-complexed bleaches for ferrocyanide bleaches wherever possible.
- Substitute less toxic metals, such as bismuth, to
function as the image carrier in the film.
Recovery and
reuse
- Reover silver by one of the following methods:
metallic replacement, chemical precipitation, electrolytic recovery or ion
exchange.
- Use technologies such as evaporation or
electrodialysis to recover metals such as chromium from waste rinse water
before treatment.
- Recycle spoiled photographic film and paper to
reclaim silver.
- Regenerate spent ferricyanide bleach by one of the
following methods: ozone oxidation, electrolysis, use of persulfate salts
or use of liquid bromine.
This Pollution Prevention Fact Sheet is just one of the many resources available
to you from DEQ. DEQ, through its Office of Pollution Prevention, provides free,
voluntary, non-regulatory technical assistance and materials to industry,
governments, academia, non-profit organizations and the general public on how to
prevent pollution. For more information on pollution prevention strategies and
techniques, please contact:
Office of Pollution Prevention
Virginia Department of Environmental
Quality
629 East Main Street, 5th Floor
P.O. Box 10009
Richmond,
Virginia 23240-0009
(804) 698-4545, FAX (804) 698-4346
e-mail: rtgriffin@deq.state.va.us
Updated 9/29/97