Abstract: A charging device for a shaft furnace, which includes at least one charging hopper having a discharge orifice arranged in a position off-centre with respect to the central axis of the shaft furnace, and a material distribution device arranged below this hopper. The material distribution device includes a feed channel coaxial with the central axis of the furnace and a rotatable, pivotable chute, which is arranged below the feed channel for distributing a charge in the shaft furnace. The charging device also includes a connecting box in the shape of a funnel, arranged between the material distribution device and the charging hopper. The connecting box possesses a lower central outlet communicating with the charging hopper and at least one upper inlet which is arranged off-centre with respect to the central axis of the furnace and communicates with the discharge orifice of the hopper.

Abstract: A checker brick (10), in particular for hot blast stove, has a top surface (12) and an opposite bottom surface (14), wherein a plurality of through passages (16) extend from the top surface (12) to the bottom surface (14) for allowing fluids to circulate through the checker brick (10), partition walls (18) being formed between neighbouring through passages (16). According to an aspect of the invention, the through passages (16) have a cross-section based on a hexagonal shape (20) having alternating convex (24) and concave sides (26).

Abstract: A charging device (1 10; 210; 310; 410; 510; 610, 710) for distributing bulk material in an enclosure, in particular in a shaft furnace comprises a stationary housing (12) that supports a rotatable structure (14) carrying adjustable distribution means (16). Distribution of bulk material in circumferential direction is achieved by rotation of the distribution means (16) together with the rotatable structure (14). Distribution of bulk material in radial direction is achieved by adjustment of the distribution means (16). For rotating the distribution means, usually about the central axis (A) of the charging device, the device (1 10; 210; 310; 410; 510; 610, 710) includes a first rolling bearing (122) with a first stationary race (124; 324) that bears a first rotary race (128). The first rotary race is coupled to a first gear ring (130; 430; 530; 730) that cooperates with a first drive (50) for rotating the rotatable structure and thereby the distribution means.

Abstract: The present invention proposes a charge distribution apparatus for a furnace comprising a charge distribution chute and a drive mechanism (12) with a first rotary drive shaft (14) for rotating the charge distribution chute and a second rotary drive shaft (16) for changing the angle of inclination of the charge distribution chute. The first and second drive shafts (14, 16) are coupled to respective first and second motors (18, 22) via a planetary gear mechanism (20) for driving the first and second drive shafts (14, 16).

Abstract: A method for constructing a support ring in a curved wall, in particular around an opening in a curved wall of a hot blast stove, wherein the method includes providing a plurality of standardized wedge-shaped bricks with side faces having tongue and groove profiles for cooperating with the side faces of the neighbouring bricks, the thickness of the brick in the axial direction being in excess of the desired end thickness of the brick, and determining the intended location of each individual brick in the curved wall and determining, based on the intended location, the location of a front cut line and a rear cut line for shaping the front and rear faces of the brick, where the front and rear faces of the brick are then shaped in accordance with the above determined front and rear cut lines by a cutting tool.

Abstract: A process for recovering non-ferrous metals, in particular copper, nickel and cobalt, from metallurgical residues containing these non-ferrous metals at an oxidation state of greater than or equal to zero, in an alternating current type plasma arc electric furnace comprising a plurality of electrodes, containing a liquid copper heel covered by a fluid slag comprising at least one fusion-reduction phase, comprising charging of metallurgical residues comprising the non-ferrous metals onto the heel contained in the plasma arc electric furnace, fusion of the metallurgical residues in the fluid slag or at the slag-metal bath interface, reduction of at least the non-ferrous metals to oxidation state zero, and intense stirring of the copper heel by injection of inert gas, preferably nitrogen and/or argon, so as to avoid crust formation and to accelerate the reduction reaction and to cause the copper-miscible non-ferrous metals to pass into the copper heel.

Abstract: A method for calibrating a weighing system of a blast furnace top hopper and a corresponding weighing system are disclosed. The method comprises the step of using at least one actuator for exerting a vertical net force with a certain magnitude onto the hopper, so as to simulate a certain weight of charge material in the hopper; and the step of determining the magnitude of the vertical net force. According to the invention, the method further comprises the step of determining the magnitude of a pressure exerting a lifting force onto said hopper and the step of using the determined magnitude of the vertical net force and the determined magnitude of the pressure to establish calibration data for the weighing system.

Abstract: A coke oven piping system (10) comprises a pipe assembly for conveying coke oven gases (14) from a coke oven to a collecting main (16); and flow control means comprising a flow orifice (22) in the pipe assembly with an associated obturating member (20), the obturating member being axially moveable between an open position at a certain distance from the flow orifice to a closed position in which it substantially obstructs the flow orifice (22). At least one throttling opening (28) is arranged so as to offer, towards the end of the closing stroke of the obturating member (20), an opening area for the gases to the collecting main (16) that depends on the axial position of the obturating member (20).

Abstract: A shaft furnace bleeder valve for controlling a gas outflow from the interior of a pressurized furnace to the ambient atmosphere through an exhaust conduit is proposed. The bleeder valve comprises a valve seat associated with the exhaust conduit, a movable closure member having a central closure surface and a peripheral sealing surface cooperating with the valve seat, the closure surface comprising a convex surface at least in proximity to the sealing surface. The valve further has an actuating mechanism, which is connected to the closure member for moving the closure member between a closed position on the valve seat and an open position distant from the valve seat.

Abstract: The present invention describes a method for treating residues comprising zinc ferrites and non-ferrous metals selected from among the group made up of lead (Pb), silver (Ag), indium (In), germanium (Ge) and gallium (Ga) or mixtures thereof in the form of oxides and sulfates, comprising the following steps: roasting of the residues in an oxidising medium at elevated temperature in order to obtain a desulfurised residue, carburising reduction/smelting of the desulfurised residue in a reducing medium, liquid phase extraction of carburised melt and slag, vapour phase extraction of the non-ferrous metals, followed by oxidation and recovery thereof in solid form.

Abstract: A coke oven offtake piping system including a pipe assembly for conveying coke oven gases from a coke oven to a collecting main, at least one spraying nozzle in pipe assembly, and a discharge section with a discharge pipe having a discharge orifice, where a gate member cooperates with the discharge orifice and is movable along the discharge orifice in order to present a closing surface to the extremity thereof, whereby the opening area of said discharge orifice can be varied for controlling the flow rate to the collecting main.

Abstract: “A flow control valve for fluidized material comprises a valve housing having a valve chamber with a valve seat and a valve plug having a flow passage, the valve plug being arranged inside the valve chamber in front of the valve seat (30) so as to be rotatable about an axis of rotation for controlling a flow through the flow control valve. It further comprises spring means biasing the valve plug against the valve seat perpendicularly to the axis of rotation, for achieving a sealing contact between the valve seat and the valve plug. According to an important aspect of the invention, the spring means comprises at least one cantilever spring (40) arranged in a clearance space opposite to the valve seat (30) so as to bias the valve plug against the valve seat.

Abstract: The inventive multi-level furnace comprises a furnace wall delimiting a cylindrical space having a vertical axis, a plurality of beds defining the levels inside said cylindrical space and at least one scraping arm which is provided with a wall scraper and associated with the bed in such a way that it is rotatable about the vertical axis of the furnace. During scraping arm rotation, said wall scraper defines a scraped area on the internal surface of the furnace wall which comprises a plurality of wall cavities forming a row of access openings in the scraped area, thereby making it possible to avoid the formation of a hardened crust adhered to the internal surface of the furnace wall and to develop braking shocks in the scraping arm.

Abstract: The invention describes a method for recovering molybdenum, nickel, cobalt or their mixtures from used or regenerated catalysts in an electric arc furnace containing a heel of liquid cast iron, surmounted with a fluid slag, comprising the following steps: a) adding used or regenerated catalysts into the heel contained in the electric arc furnace, b) adding dosed lime in order to obtain a slag with a CaO to Al2O3ratio comprised between 0.7 and 1.3, c) mixing the heel by injecting gas so as to avoid formation of crusts, d) melting the used or regenerated catalysts in the electric arc furnace in order to obtain a liquid ferro-alloy.

Abstract: A multiple hearth furnace including a rabble arm with a tubular structure and a solid plug body. The latter is received in a socket arranged in an arm fixing node. It has an axial through boring and cooling fluid supply and return channels arranged around this through boring. A clamping bolt is rotatably fitted in the through boring. It has a bolt head, which can be brought by rotation into and out of hooking engagement with an abutment surface on the arm fixing node. A threaded end of the clamping bolt sticks out of the through boring at the rear end of the plug body. A threaded sleeve, which is screwed onto this threaded end, bears on an abutment surface at the rear end of the plug body for exerting a clamping force onto the clamping bolt.

Abstract: A multiple hearth furnace includes a gas cooling system for its central shaft and its rabble arms. This gas cooling system includes within the shaft an annular main distribution channel for supplying a cooling gas to the rabble arms and a central exhaust channel for evacuating the cooling gas leaving the rabble arms. The gas cooling system further includes an annular main supply channel surrounding the annular main distribution channel and being outwardly delimited by an outer shell of the shaft. A cooling gas inlet is connected to the annular main supply channel. A cooling gas passage between the annular main supply channel and the annular main distribution channel is spaced from the cooling gas inlet, so that cooling gas supplied to the cooling gas inlet has to flow through the annular main supply channel through several hearth chambers before it flows through the cooling gas passage into the annular main distribution channel.

Abstract: “A ceramic burner for use in a combustion chamber of a regenerative heat generator, such as a hot blast stove of a blast furnace, the ceramic burner including a burner feed chamber with a partition wall for dividing the burner feed chamber into a fuel chamber and an air chamber, where the fuel chamber has a fuel inlet for receiving combustible fuel and a fuel outlet for feeding the combustible fuel to a mixing zone (34), the air chamber having an air inlet for receiving combustion air and an air outlet for feeding the combustion air to the mixing zone, where the ceramic burner further includes a gastight metallic fuel container arranged in the burner feed chamber, the fuel container including the fuel chamber therein, a wall portion of the fuel container forming the partition wall between the fuel chamber and the air chamber.

Abstract: A rotary charging device (10) for a shaft furnace commonly comprises a rotary distribution means (12) for distributing charge material on a charging surface in the shaft furnace. A rotatable structure supports (16) the rotary distribution means and a stationary support (18) rotatably supports the rotatable structure. According to the invention, the charging device (10) is equipped with an inductive coupling device (30) including a stationary inductor (34) fixed to the stationary support and a rotary inductor (36) fixed to the rotatable structure. The stationary inductor (34) and the rotary inductor (36) are separated by a radial gap and configured as rotary transformer for achieving contact-less electric energy transfer from the stationary support (18) to the rotatable structure (16) by means of magnetic coupling trough the radial gap for powering an electric load arranged on the rotatable structure (16) and connected to said rotary inductor (36).

Abstract: Process and apparatus for the treatment of divided metal residues contaminated by one or more organic compounds, comprising: mixing, inside a chamber, of said metal residues with at least one calcium/magnesium compound capable of reacting exothermically with water; exothermic reaction of said at least one calcium/magnesium compound with the water that the metal residues contain; rise in temperature of the metal residues subject to an exothermic reaction; dehydration of said metal residues during this exothermic reaction; oxidation of the organic compounds during said mixing, by bringing the metal residues contaminated by one or more organic compounds mixed with said at least one calcium/magnesium compound into contact with a gas stream containing at least partly oxygen; and removal from the chamber of a handleable dehydrated treated product having a residual content of organic compounds of less than 1% by weight of said treated product.

Abstract: The present invention proposes a pulverized coal injection lance (10) for feeding pulverized coal from a rear end of the lance (10) to a front end (11) of the lance (10). The lance (10) comprises an outer pipe (12) for conveying combustive gas, and an inner pipe (14), coaxially arranged within the outer pipe (12), for conveying pulverized coal. The inner pipe (14) forms a separation wall for separating the pulverized coal from the combustive gas. The separation wall is at least partially discontinued in a region near the front end (11) of the lance (10), thereby forming a mixing region (16) within the pulverized coal injection lance (10). According to an important aspect of the invention, the outer pipe (12) and the inner pipe (14) have substantially the same length and wherein the inner pipe (14) comprises at least one lateral opening (18, 20) for allowing pulverized coal and combustive gas to come into contact within the pulverized coal injection lance (10) near the front end (11).