Process for calcining mineral rock in a regenerative parallel-flow vertical shaft furnace, containing at least two shafts (1, 2) interconnected by a gas transfer channel (3), each shaft operating alternately in firing mode and in preheating mode, the firing mode comprising a combustion of fuel in the presence of air so as to obtain a firing of the rock to give calcined rock, an emission of combustion gases, and a passage of these gases from one shaft to the other by means of said channel (3), the preheating mode comprising a heat exchange between said rock and said combustion gases from said channel (3), this process additionally comprising an injection of supplementary air into said channel (3) with oxidation of unburnt products contained in the combustion gases passing through this channel.

Process for calcining mineral rock in a regenerative parallel-flow vertical shaft furnace, containing at least two shafts (1, 2) interconnected by a gas transfer channel (3), each shaft operating alternately in firing mode and in preheating mode, the firing mode comprising a combustion of fuel in the presence of air so as to obtain a firing of the rock to give calcined rock, an emission of combustion gases, and a passage of these gases from one shaft to the other by means of said channel (3), the preheating mode comprising a heat exchange between said rock and said combustion gases from said channel (3), this process additionally comprising an injection of supplementary air into said channel (3) with oxidation of unburnt products contained in the combustion gases passing through this channel.

An injector configured for arrangement within a reactor of a vertical furnace to inject gas in the reactor is provided. The injector is made substantial elongated and configured with an internal gas conduction channel to transport gas from a first end of the injector to a second end of the injector. An outer sidewall of the injector may be tapered towards the second end over at least 10%, preferably 30% and most preferably 50% of the length of the injector to increase tolerances for fitting the injector in the tube.

An injector configured for arrangement within a reactor of a vertical furnace to inject gas in the reactor is provided. The injector is made substantial elongated and configured with an internal gas conduction channel to transport gas from a first end of the injector to a second end of the injector. An outer sidewall of the injector may be tapered towards the second end over at least 10%, preferably 30% and most preferably 50% of the length of the injector to increase tolerances for fitting the injector in the tube.

The invention relates to non-ferrous metallurgy and concerns a device for chlorinating titanium-containing material in a solution of chloride salts. The technical effect of the invention is an increase in the service life of the device and a reduction in raw material losses. This technical effect is achieved by means of the proposed device for chlorinating titanium-containing material in a solution of chloride salts, comprising a housing, a lined upper cylindrical chamber for a gas-vapour mixture, a lined chlorinating chamber in the shape of an inverted truncated cone, the generatrix of which is inclined at an angle of 15-25° to the axis of the chamber, graphite electrodes, a hearth, tuyeres, chlorine feed lines, and a feedstock charging assembly, wherein the housing is provided with reinforcing ribs in the region of the chlorinating chamber and of an upper drainage pocket.

The invention relates to non-ferrous metallurgy and concerns a device for chlorinating titanium-containing material in a solution of chloride salts. The technical effect of the invention is an increase in the service life of the device and a reduction in raw material losses. This technical effect is achieved by means of the proposed device for chlorinating titanium-containing material in a solution of chloride salts, comprising a housing, a lined upper cylindrical chamber for a gas-vapour mixture, a lined chlorinating chamber in the shape of an inverted truncated cone, the generatrix of which is inclined at an angle of 15-25° to the axis of the chamber, graphite electrodes, a hearth, tuyeres, chlorine feed lines, and a feedstock charging assembly, wherein the housing is provided with reinforcing ribs in the region of the chlorinating chamber and of an upper drainage pocket.

A blank for a conduit arrangement includes an annular conduit having a first end and a second end, which is formed by a channel surrounded by a wall. The conduit arrangement has an axis of rotation and the conduit extends in a circumferential direction over an angle of more than 360 degrees about the axis of rotation and forms at least one wind turn. The axis of rotation is arranged perpendicularly to a base surface, the wall having first surfaces which are arranged at a first angle of at least 30 degrees relative to the base surface or in which a surface normal forms at least one second angle of 0 to 60 degrees with respect to the base surface. First partial surfaces of the walls, which face one another in an axial direction, of adjacent turns are arranged spaced apart from one another. The blank is produced by an additive manufacturing process.

A method for reducing molten raw materials, includes placing the raw materials, in a solid or molten state, on an inductively heated bed with coke pieces. The reduced melt that runs off the coke bed is collected and the waste gases are discharged. A coke bed is inwardly limited by a tube-shaped element through which the reaction gases are drawn off via a plurality of draw-off openings in the tube-shaped element. The corresponding device has a reactor for a bed with coke pieces and an induction heater with at least one induction coil. The reactor has a loading opening and a discharge opening for the treated melt. The coke bed is ring-shaped around a tube-shaped element. The material of the tube-shaped element allows inductive coupling to the induction field of the induction coil and it has draw-off openings for drawing off reaction gases from the coke bed.

A method for reducing molten raw materials, includes placing the raw materials, in a solid or molten state, on an inductively heated bed with coke pieces. The reduced melt that runs off the coke bed is collected and the waste gases are discharged. A coke bed is inwardly limited by a tube-shaped element through which the reaction gases are drawn off via a plurality of draw-off openings in the tube-shaped element. The corresponding device has a reactor for a bed with coke pieces and an induction heater with at least one induction coil. The reactor has a loading opening and a discharge opening for the treated melt. The coke bed is ring-shaped around a tube-shaped element. The material of the tube-shaped element allows inductive coupling to the induction field of the induction coil and it has draw-off openings for drawing off reaction gases from the coke bed.

A furnace may include at least two vertical shafts, each of which may have at an upper end thereof an inlet for material to be burnt and at a lower end thereof a burnt material outlet. The inlet and the outlet may be connected by a transfer channel. In each case, at least one main burner may be positioned above the transfer channel, and a cooling gas inlet may be positioned below the transfer channel. At least one additional burner may be positioned below the transfer channel in each of the shafts. Such a furnace can be operated such that the material to be burnt in the currently fired shaft is at least partially calcined in a main burning zone above the transfer channel, and then thermally aftertreated in an additional burning zone positioned between the transfer channel and the additional burner.