Silver recovery from photographic wastes
Abstract
Abstract A METHOD FOR THE RENDERING OF SILVER FROM PHOTOGRAPHIC WASTE IN WHICH THE FILM OR OTHER WASTE IS IGNITED AND BROUGHT UP TO A SATISFACTORY BURNING TEMPERATURE IN A PRIMARY CHAMBER AND MAINTAINED AT THIS TEMPERATURE UNTIL THE FILM OR WASTE IS BURNED BY CONTROLLING THE AMOUNT OF OXYGEN SUPPLIED TO THE PRIMARY CHAMBER. THE BURNING OF THE PHOTOGRAPHIC WASTE IS CONTROLLED SO THAT THE TEMPERATURE OF THE GASES AND PARTICULATE MATTER RESULTING FROM THE BURINING OF THE PHOTOGRAPHIC WASTE IS ABOVE ABOUT 1200* F. AND BELOW ABOUT 1500*F. AS THE GASES AND PARTICULATE MATTER ARE ABOUT TO LEAVE THE PRIMARY CHAMBER. DURING THE IGNITION AND BURNING OF THE PHOTOGRAPHIC WASTE THE SMOKE AND PARTICULATE MATTER IS DIRECTED TO A SECONDARY CHAMBER WHERE IT IS SUBJECTED TO BURNING AT A TEMPERATURE THAT IS HIGHER THAN THAT IN THE PRIMARY CHAMBER. AFTER THE PHOTOGRAPHIC WASTE IS BURNED, THE SILVER BEARING ASH IS COOLED AND REMOVED FROM THE PRIMARY CHAMBER. THE ASH IS THEN PROCESSED BY CONVENTIONAL TECHNIQUES TO REFINE THE SILVER. THIS METHOD PERMITS THE ECONOMICAL RENDERING OF SILVER FROM PHOTOGRAPHIC WASTE BY BURNING WITH THE ELIMINATION OR REDUCTION OF SMOKE AND OTHER AIR POLLUTANTS.
Inventors
- 👤 Edward B Johnson
Bibliographic Details
Claims Analysis
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