Boliden Aktiebolag

Johan S Leirnes

Malkolm S Lundstrom

Martin L Hedlund

Kurt J Buren

The invention relates to a method for producing lead from moist lead-sulphide concentrates and oxidic and/or sulphatic lead raw materials by the known roasting and reaction process. According to the method granules or pellets of oxidic and/or sulphatic lead raw materials are brought together with the moist lead concentrate in a drum-like vessel arranged for rotation about its longitudinal axis. Said moist concentrate is dried while rotating said drum-like vessel to form sulphide-containing granulates. The formed granulates are introduced into a furnace together with flux in given proportions. The charge is vigorously agitated and turbulence created in the resultant melt, while effecting the roasting and reaction process to form a liquid slag and a molten lead phase. Both the drying and the smelting may be provided in the same unit if a top-blown rotary converter is employed.

Method for producing lead from sulphidic and oxidic and/or sulphatic

The invention relates to a method for producing lead having a sulphur content beneath about 2%, from sulphur-containing oxidic lead raw materials contaminated with zinc and/or other readily oxidized elements, by smelting the materials in a furnace in which the furnace contents can be agitated. When practicing the method, the lead raw materials are charged to the furnace together with iron-containing fluxes and solid reduction agents. The charged materials are heated under agitation, to form a lead phase and a slag phase. The amount of reduction agent charged is selected so that at least all the lead contained in the furnace is reduced to lead metal and the amount and composition of the fluxes are selected so that a terminal slag is obtained in which the sum of the iron and zinc present is 30-40%, and so that the slag has a content of 15-25% of both SiO.sub.2 and CaO+MgO. Lead raw materials, fluxes and reduction agents are suitably introduced in a plurality of charges, with intermediate moderate heating, prior to commencing the smelting process.

Method for producing lead from oxidic lead raw materials which contain

The invention relates to a method for converting metal-containing waste material having substantial quantities of organic constituents, such as plastics, rubber, paper and greases, to a product from which metal can readily be recovered. The waste material is introduced into a reactor vessel arranged for rotation about its longitudinal axis, the vessel being provided with a bottom and a common charge and discharge opening, whereafter the reactor vessel is rotated with its axis inclined to the horizontal plane at an angle of less than 90.degree.. The reactor vessel is maintained during this rotation at a temperature which is sufficiently high to expel organic constituents in the form of a combustible gas for as long as such a gas continues to be generated. The combustible gas is combusted continuously at a location external of the reactor vessel, and the residual content of the reactor vessel is taken out in a molten and/or non-molten state. During at least a part of the expulsion process, air or gas containing free oxygen can be supplied to the reactor vessel through a lance in sub-stoichiometric amount.

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Skelleftehamn, Sweden

Johan S Leirnes