Abstract: In a process for at least temporarily simultaneously subjecting a molten metal (5) in a metallurgical vessel (3) to the action of a gas and fine-grain solid materials, with a water-cooled first lance (17) for supplying the gas, in accordance with the invention the solid materials are supplied in the form of a conveyor stream (27) by way of a second lance (19). The solid materials are supplied in such a way that, after leaving the outlet opening (25) of the second lance (19), they are deflected by the gas (29) issuing from the outlet opening (23) of the first lance (17) and are supplied with said gas to the molten metal (5).