Abstract: A process for manufacturing a vitreous slag including rotating a cone about a vertical cone axis, the cone including an external shell having a lateral surface; cooling the lateral surface of the external shell; pouring molten slag onto the lateral surface of the cone to form a film of slag by gravity, which is solidified as it is entrained in rotation by the cone about the cone axis; and detaching pieces of the film from the lateral surface and removing solidified slag in the form of the pieces after the film has been entrained through between 0.6 and 0.9 revolutions of the cone, the molten slag being poured onto the lateral surface in a pouring zone and spreads to form a film over substantially the entire length of the lateral surface, preferably over between 75% and 95% of the length of the lateral surface.

Abstract: A device for removing dross from the bottom of a molten metal bath comprises a perforated basket assembly for receiving said dross, pumping means for pumping said bottom dross and molten metal from the bottom of the molten metal bath into the perforated basket assembly when the perforated basket assembly is in a pumping position, lifting and/or rotating means for moving said perforated basket assembly from its pumping position out of said molten metal bath in a separation position and in a disposal position and separation means for separating said bottom dross from said molten metal, wherein the separation means comprise a paddle assembly capable of contacting said dross inside the perforated basket assembly with a cutting action in a first position followed by a cutting action in at least one adjacent second position, when the perforated basket assembly is in the separation position.

Abstract: The invention relates to a method for producing directly reduced, desulfurized iron in a multiple-hearth furnace which comprises two zones arranged one above the other and each having several hearths. Iron ore is reacted with a reducing agent in a first zone of the multiple-hearth furnace at a temperature ranging from 800° C. to 1100° C. to obtain metallic iron. In addition, the gases are desulfurized using desulphurizing agents, whereby the directly reduced iron is discharged from the multiple-hearth furnace and the desulfurized gases are guided into a second zone where the iron ore is preheated to a temperature ranging from 600° C. to 800° C.

Abstract: A process for thermal treatment of residual materials containing heavy metal and iron oxide, including providing a multiple-hearth furnace having hearths provided one above the other, depositing the residual materials continuously on a top hearth of the hearths, gradually transferring the residual materials to lower hearths of the hearths, introducing reducing agents to at least one of the hearths and reacting the residual materials to form heavy metals and directly reduced iron, exhausting gases containing heavy metals from below hearths of the hearths where the heavy metals are being vaporised, re-injecting at least a part of the gases into the multiple-hearth furnace from above the hearths of the hearths where the heavy metals are being vaporised, and discharging the directly reduced iron together with residues of the reducing agents in an area of a bottom hearth of the hearths in the multiple hearth furnace.

Abstract: A method for producing reduced iron in a layered furnace which includes several superimposed layers. Ore is continuously fed into the layered furnace, deposited on the uppermost layer, and gradually transferred to the lower layer. A reducing agent is deposited on the uppermost layer and/or layers thereunder and is reacted with the ore in order to form directly reduced iron. The directly reduced iron and reducing agent residues are discharged in the vicinity of the lowest layer of the furnace.

Abstract: Process for thermal treatment of residual materials containing oil and iron oxide in a multiple-hearth furnace, which has several hearths one above the other, the residual materials containing oil and iron oxide being mixed with a solid reducing agent, introduced continuously into the multiple-hearth furnace, charged on the top hearth and transferred gradually to the lower hearths, the residual materials containing oil and iron oxide being dried in the top hearths, the oil subsequently evaporated and pyrolised and the reducing agent reacting with the iron oxides to form directly reduced iron, the directly reduced iron being discharged with residues of reducing agents in the areas of the bottom hearth of the multiple-hearth furnace.

Abstract: The invention relates to a method for the heat treatment of residues containing heavy metals, carried out in a multiple-hearth furnace which is divided into three zones, each of which comprises several stacked levels. Said method consists of the following steps: continuous feeding of the heavy-metal residues into the top level of the first zone of the multiple-hearth furnace, the residues being gradually transferred to the second zone and dried during the transfer; continuous feeding of reducing agents and desulfurizers into the top level of the second zone, whereby the reducing agents and desulfirizers are mixed with the dried residues and the mixture is heated to approximately 800° C., calcined during heating and gradually transferred to the third zone; heating of the mixture to approximately 1000° C. in the third zone, whereby the metals are reduced and the waste gases resulting in said third zone are drawn off and treated separately; and discharge of the mixture from the multiple-hearth furnace.

Abstract: A process for thermal treatment of residual materials containing heavy metal and iron oxide, including providing a multiple-hearth furnace having hearths provided one above the other, depositing the residual materials continuously on a top hearth of the hearths, gradually transferring the residual materials to lower hearths of the hearths, introducing reducing agents to at least one of the hearths and reacting the residual materials to form heavy metals and directly reduced iron, exhausting gases containing heavy metals from below hearths of the hearths where the heavy metals are being vaporised, re-injecting at least a part of the gases into the multiple-hearth furnace from above the hearths of the hearths where the heavy metals are being vaporised, and discharging the directly reduced iron together with residues of the reducing agents in an area of a bottom hearth of the hearths in the multiple hearth furnace.

Abstract: The invention relates to a charging device for creating superimposed layers of fine-grained bulk material on a rotating hearth (2). For each layer of bulk material to be charged, said charging device comprises a discharge hopper (22) having an outflow slot (36) and a discharge roller (42) positioned ahead of each outflow slot (26). Said outflow slot (36) and discharge roller (42) extend essentially at a right angle to the direction of rotation of the rotating hearth and the discharge roller (42) has a drive (44), the rotational frequency of which can be controlled.

Abstract: A device for the discharge of bulk material (96) from a pressure vessel (2) is proposed, which comprises at least one sluice bin (24, 26) with a bottom (42, 44) and a top (40) sluice gate. The sluice bin (24, 26) is arranged under a plate (76, 76'), into which it forms an orifice (28, 30) for the bulk material (96). The top sluice gate (40) has a sealing plate (66), which is arranged above this plate (76, 76') in such a way that it can be positioned above the orifice (28, 30) of the sluice bin (24, 26) and, after a sealing connection to the edge of the orifice (28, 30) has been made, can be forced against this edge by overpressure in the pressure vessel (2).

Abstract: A device in which a mixture of steam and contaminated air is first of all channelled into an upward stream and that the mixture subsequently flows as a downward stream in a vessel maintained at reduced pressure. The device further includes an arrangement for spraying an alkaline aqueous solution into the downward stream of the mixture of steam and contaminated air. The decontaminated uncondensed gases are thereby removed from the vessel by a forced and adjustable stream which creates and maintains a reduced pressure inside the vessel.

Abstract: An isolation and flow control valve in a furnace charging installation, installed in a discharge conduit of a storage hopper which may be alternately at ambient pressure for loading and furnace pressure for discharging, is characterized by a valve member which is caused to move serially in two directions during opening and closing. The movement is produced by an actuator mechanism including a pivot arm and a cam system and results in movement axially with respect to the conduit for seating and unseating and generally transverse to the conduit axis for controlling material flow through the conduit.