| 摘要 |
<p>In an intermittently-operating electrolytic cell for the recovery of silver from used photographic bleach-fix solution, the cathode assembly and the solution are automatically separated when the plating current is switched off. A buffer tank upstream of the cell, from which solution is delivered to the cell by a metering pump during plating, has a bottom level switch that switches off the cell and feed and switches on an emptying pump for pumping the cell solution back to the buffer tank. The emptying pump is stopped by a cell bottom level switch; and a filling pump is started by a top level switch of the buffer tank, which also starts the plating cell and the metered feed, the filling pump being stopped by a top level switch of the cell. The cathode assembly is self-draining.</p> |
