A method and system of controlling a melting process of copper in a copper melting furnace including measuring at least one furnace parameter, wherein the at least one furnace parameter includes one or both of a furnace temperature and a furnace exhaust oxygen concentration, calculating a first rate of change of the furnace parameter over a first time period, calculating a second rate of change of the furnace parameter over a second time period at least a portion of which occurs after the first time period, comparing the first rate of change with the second rate of change, and indicating substantial completion of a process phase in the furnace when the second rate of change deviates by a predetermined threshold percentage from the first rate of change.

A method and system of controlling a melting process of copper in a copper melting furnace including measuring at least one furnace parameter, wherein the at least one furnace parameter includes one or both of a furnace temperature and a furnace exhaust oxygen concentration, calculating a first rate of change of the furnace parameter over a first time period, calculating a second rate of change of the furnace parameter over a second time period at least a portion of which occurs after the first time period, comparing the first rate of change with the second rate of change, and indicating substantial completion of a process phase in the furnace when the second rate of change deviates by a predetermined threshold percentage from the first rate of change.

Ultrasonic probes containing a plurality of gas delivery channels are disclosed, as well as ultrasonic probes containing recessed areas near the tip of the probe. Ultrasonic devices containing these probes, and methods for molten metal degassing using these ultrasonic devices, also are disclosed.

Provided is a method for producing cathode copper. The method comprises a smelting step including feeding sulfidic copper bearing material and oxygen-bearing reaction gas into a suspension smelting furnace, to produce blister copper, a fire refining step including feeding blister copper into an anode furnace to produce molten anode copper, an anode casting step to produce cast anodes, a quality checking step for dividing cast anodes into accepted cast anodes and rejected cast anodes, an electrolytic refining step including subjecting accepted cast anodes to electrolytic refining in an electrolytic cell to produce cathode copper and as a by-product, spent cast anodes, and a recycling step for recycling anode copper of rejected cast anodes and anode copper of spent cast anodes.

A method for obtaining metals of the 8th to 14th groups, in particular raw copper, comprises the following steps: i) providing and melting down a mixed feed comprising electronic waste in a smelting reactor, so that a first melt with a first metallic phase and a first slag phase is formed; ii) separating out the first slag phase from the smelting reactor; iii) refining the remaining first metallic phase by means of an oxygen-containing gas, possibly with the addition of copper-containing residual materials, so that a second, copper-enriched slag phase is formed; iv) possibly separating off the second slag phase and repeating the step; v) separating off the refined first metallic phase from the smelting reactor; and vi) adding a further mixed feed comprising electronic waste to the remaining second, copper-enriched slag phase and repeating process steps i) to vi).