Silver Recovery with RenoCell Technology

Unidragmet BGU, UE, Minsk, Belarus

There are several reasons to be interested in the recovery of silver from photoprocessing waste. Silver is a valuable natural resource of finite supply, it has monetary value as a recovered commodity, and it’s release into the environment is strictly regulated. In photoprocessing, silver compounds are the basic light-sensitive material used in most of today’s photographic films and papers. During processing, particularly in the fixing bath or bleach-fix, silver is removed from the film or paper and is carried out in the solution, usually in the form of a silver thiosulfate complex.

Major sources of recoverable silver are: photoprocessing solutions, spent rinse water, scrap film, and scrap printing paper. As much as 80 percent of the total silver processed for black and white positives and almost 100 percent of the silver processed in colour work will end up in the fixer solution. Silver is also present in the rinse water following the fixer or bleach-fix due to carry-over.

“Unidragmet BGU”, selected RenoCell technology supplied by Efftech Ltd for electrowinning silver from fixing solutions used in fluorography and the printing industry. The process desilvers around 800litres of solution every day with RenoCell reducing silver levels left in solution to 1mg/l or less.

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