Abstract: Silver is recovered from used film plates by passing them into a solution into which their silver material is dissolved and by electroplating the dissolved silver out of the solution. Electrical circuits are provided to increase the magnitude of a continuous plating current in proportion to the rate of film and silver input and to decrease the current gradually to coincide with the decrease in silver concentration as plating continues.

Abstract: Electrical current used in electrolytic recovery of metals, such as silver, is controlled digitally by causing pulses from an oscillator operating at a first frequency to be counted during introduction of silver bearing salts into solution and causing the electroplating current to correspond to the cumulative count. Thereafter, following salt introduction, the oscillator is operated at a second frequency, corresponding to the previously accumulated count, and the counter is counted down at this second frequency while the electroplating current is correspondingly reduced.

Abstract: Portable apparatus is disclosed for recovering metal from metal bearing solutions. The apparatus includes a chamber arranged to be mounted on a container for the solution to establish a fluid flow path between an anode and cathode in the chamber for deposition of metal on the cathode, the unit being arranged to prevent unauthorized removal of deposited metal from the cathode.

Abstract: Silver is recovered from used film plates by passing them into a solution into which their silver material is dissolved and by electroplating the dissolved silver out of the solution. Electrical circuits are provided to increase the magnitude of a continuous plating current in proportion to the rate of film and silver input and to decrease the current gradually to coincide with the decrease in silver concentration as plating continues.