Abstract: The top-submergable injection lance has an elongate conduit which extends between upper and discharge ends and defines a bore, for the supply of reactants, through the conduit and an annular, alloy steel tip at the discharge end. The conduit comprises an inner pipe defining the bore, an outer pipe, and a third pipe which divides an annular volume between the inner and an outer pipes for circulation of coolant fluid. The tip is defined by inner and outer peripheral surfaces merging at a sharp lower edge and a top surface extending between the peripheral surfaces. The top surface of the tip joins the inner and outer pipes so as to be contactable by the coolant fluid. The frusto-conical inner peripheral surface provides a continuation of the bore which increases in cross-section to an opening at the lower edge.

Abstract: A process for smelting metallurgical waste material containing at least one iron compound, at lest one heavy metal, and at least one toxic element. The waste material and a reductant are introduced into a furnace. Heat is applied to the waste material and to the reductant to form a melt under reducing conditions whereby volatilization of the heavy metal occurs and a matte or speiss is formed in which the toxic element is stabilized. Fuel and an oxidizing gas are introduced into the melt by submerged injection to create a submerged oxidizing region. The melt is circulated to the submerged oxidizing region and is oxidized causing volatilization of the toxic element stabilized in the matte or speiss.