In the US the discharge limits are typically usually less than 1 ppm of
silver for discharges to municipal sewers and much less for straight
discharges to rivers and other water bodies. In many European countries
they are not allowed to discharge fixers and other chemistry from
photodeveloping and must have it hauled away by a licensed hauler.
If you want more information on silver recovery or to discuss this further
please give me call.
Environmental Activities Dept.
Photo Marketing Association Int'l
From: Sharma, Aarti [mailto:sharma@RTI.ORG]
Sent: Tuesday, April 13, 1999 8:55 AM
Cc: Bahner, Mark A.
Subject: Rinse water for photographic plates and scrap paper generation rates
We are working with a printing company outside the US that does Offset
lithography and are having trouble finding some specific environmental / P2
performance information that the company is interested in - would someone on
this listserver be able to shed some light on the following?
1. How much rinse water do the "best" US plants typically use for rinsing
fixing solution or "hypo" off from photographic plates? Is this water
pretreated prior to discharge?
Background: When this company rinses "fixing" solution from their plates
(it's also called sodium thiosulfate, or "hypo"), they use approximately 6.2
gallons of water per plate. (106,000 gallons/year for approximately 17,000
plates). The rinse water with the "hypo" goes down a drain, and directly
into a canal leading to the river.
2. What are "average" and "best" numbers for scrap paper produced in a
comparable offset litho plant.
Background: This company produces 275 tons per year of printed sheet
products, and 275 tons per year of books, magazines, booklets, catalogs, and
posters. I have printing press models and ages, if this will help.
Thank you very much for your help!