Silver recovery and fixer management: a new approach.

Existing methods of silver recovery need more attention than can be devoted to them by the staff of radiographic departments if they are to be operated at full efficiency. A study of the problems involved has led to the design of an electrolytic cell having a stainless steel anode and an expendable, carbon-fibre cathode. The fixing bath is recycled through the cell which maintains a low concentration of silver, thus cutting down the volume of replenisher required and the loss of silver to effluent, and improving the washing. The fixer can be run indefinitely without replacement, the tendency to discolour through the oxidation of developing agents being controlled partly by the use of the metal anode and partly by an absorptive resin. The operation of the system is controlled by a microprocessor that recognises the formats of the sheets of film being fed to the processor, maintains an inventory of the films used, and silver recovered, and adjusts the time of electrolysis as required. The microprocessor speaks to the operator, acknowledging the input of work, and will advise of any malfunction, or of the need to replace the cathode when fully loaded. The stored information is available to the holder of a key.