A method and device for depleting copper smelting slag. The method comprises mixing copper smelting molten slag (1) with a reductant (2) and an inert gas (3) under pressure, and then depleting same. The device for depletion comprises a furnace body (4), which furnace body (4) is provided with a feed opening (413) and a slag discharge port (416), and gas nozzles (411) disposed on the side wall of the furnace body.

An integral melter and pump assembly or system, and a method of making the same, is disclosed wherein the pump assembly comprises a melter housing having a melter container defined within the melter housing. A pump mounting plate is integrally mounted within a side wall portion of the melter container and an output dispensing supply pump is mounted directly upon an external surface portion of the pump mounting plate in a surface-to-surface manner such that heat generated internally within the melter container is effectively transferred by conduction from the melter container and through the pump mounting plate such that the temperature level of the output pump is elevated to, and maintained at, a predeterminedly desired level even when the pump, is not disposed in its output dispensing mode. In addition, since the output dispensing or material supply pump is disposed externally of the melter container and the melter housing, the output dispensing or material supply pump is easily and readily accessible in case maintenance becomes necessary. Optionally, an oil jacket or chamber can surround the melter container so as to more evenly or consistently provide heating of the melter container.