Abstract:
A method of generating hydrogen gas is disclosed. The method includes a first step of contacting an aqueous solution of a chemical hydride and a catalyst and producing hydrogen gas and a heated hydrogen-depleted solution. The hydrogen gas is recovered and used as required, for example in a fuel cell. The heated solution is brought into direct or indirect heat exchange relationship with a metal hydride, thereby heating the metal hydride and causing desorption of hydrogen from the metal hydride and producing hydrogen gas and cooling the heated solution and producing a cooled solution. The hydrogen gas is recovered and used as required.
Abstract:
A direct smelting plant for producing molten metal from a metalliferous feed material is disclosed. The plant includes a fixed smelting vessel to hold a molten bath of metal and slag and a gas space above the bath. The plant also includes means for supplying solids and gas feed materials to the vessel and for tapping molten material from the vessel. The plant also includes at least two platforms for supporting plant operators at different heights of the vessel. The metal tapping means and the slag tapping means are located so as to be accessible by plant operators on a cast house platform and the end metal tapping means and the end slag tapping means are located to be accessible by plant operators on an end tap platform that is at a lower height than the cast house platform.
Abstract:
A solids feed means for a direct smelting plant is disclosed. The solids feed means includes 2 or more pairs of lances for injecting solid feed materials for a direct smelting process into a direct smelting vessel. The solids feed means also includes a main supply line and a pair of branch lines for supplying solid feed material to the lances of each pair of lances with the branch lines interconnecting the main supply line and the lances of the pair of lances. The lances are arranged around the vessel in pairs of diametrically opposed lances. At least one pair of lances is provided for injecting metalliferous feed material (such as iron-containing materials, particularly iron ore fines) and at least one of the other pairs of lances is provided for injecting solid carbonaceous material (such as coal) and optionally fluxes. The pairs of lances are arranged around the vessel so that adjacent lances are lances that are provided to inject different materials.
Abstract:
A direct smelting process for producing iron and/or ferroalloys on a commercial scale in a metallurgical vessel is disclosed. The process includes injecting solid feed materials into a molten bath via multiple solids injection lances (27) and injecting post-combustion oxygen-containing gas into the vessel via one or more lance (26). The process is characterised by selecting the numbers of solids injection and oxygen gas injection lances and the relative positions of these lances and controlling process operating conditions so that: (i) an expanded molten bath zone (28) that has a raised region (70) forms around the oxygen gas injection region of the vessel between the region and the side walls of the vessel; (ii) splashes, droplets and streams of molten material project upwardly from the raised region and form a curtain (72) around the oxygen gas injection region between the region and the vessel side walls and wet the side walls; and (iii) a "free" space (29) forms around a lower end of the or each oxygen gas injection lance, the free space having a concentration of molten material that is lower than the molten material concentration in the expanded molten bath zone.
Abstract:
A direct smelting process for producing iron and/or ferroalloys is disclosed. The process operates on a commercial scale in a metallurgical vessel that has a hearth, side walls, and a roof, and a minimum width dimension of the interior of the hearth of at least 4 meters. The process is a molten bath-based process and includes supplying ferruginous material, carbonaceous material, and fluxes into the vessel and smelting ferruginous feed material to molten metal in the molten bath and generating gases in the bath. The process also includes injecting jets of oxygen-containing gas being air or air with up to 50% oxygen through 3 or more lances into a space above the quiescent surface of the molten bath (the "top space") and combusting gases generated in the process and generating upward movement of molten material from the molten bath into the top space to facilitate heat transfer to the bath and to minimise heat loss from the vessel. The process is characterised by entraining a volume of top space gas into the jets of oxygen-containing gas injected into the vessel that is 2-6 times the volume of the injected gas.
Abstract:
A process and apparatus for supplying solid feed materials for a direct smelting process to solids injection lances of a direct smelting vessel is disclosed. The feed materials supply apparatus includes a supply line (L) for conveying iron-containing material and solid carbonaceous material under pressure to solids injection lances (7), and the supply line includes a main feeder line section (15) and a plurality of branch line sections (17) extending from the main feeder line section. Each branch line section is connected to one solids injection lance for supplying iron-containing material and carbonaceous material to that lance. The apparatus further includes an assembly for dispensing iron-containing material under pressure into the main feeder line section of the supply line and an assembly for dispensing carbonaceous material under pressure into the main feeder line section of the supply line.
Abstract:
A molten bath-based direct smelting process for producing ferrous metal from a ferrous feed material is disclosed. The process is characterised by injecting pre-heated air downwardly into metallurgical vessel at an angle of 20 to 90 DEG C relative to a horizontal axis and at a temperature of 800-1400 DEG C and at a velocity of 200-600 m/s via at least one lance (27). This step forces molten material in the region of a lower end of the lance away from the lance and forming a "free" space around the lower end of the lance that has a concentration of molten material that is lower than the molten material concentration in the raised bath. The process is further characterised in that the lance is located so that: (i) the lance extends into the vessel a distance that is at least the outer diameter of the lower end of the lance; and (ii) the lower end of the lance is at least 3 times the outer diameter of the lower end of the lance above a quiescent surface of the molten bath.
Abstract:
An elongate metallurgical lance (27) for injecting solid particulate material into molten material held within a vessel (11) is disclosed. The lance includes a central core tube (31) through which to pass solid particulate material, an annular cooling jacket (32) surrounding the central core tube throughout a substantial part of its length, a coolant inlet means (52), and a coolant outlet means (53). An outer wall of a forward end section of the jacket is formed from a first material which has high heat transfer properties and can withstand external temperatures above 1100° C. for prolonged periods when the jacket is cooled by coolant flow. An outer wall of a body section of the jacket is formed from a second material that maintains its structural properties when exposed to external temperatures above 1100° C. for prolonged periods when the jacket is cooled by coolant flow, whereby the outer wall acts as a structural member that contributes to supporting the lance at these temperatures. The outer wall of the forward end section and the outer wall of the body section are welded together.
Abstract:
A process and an apparatus for producing metals from a metalliferous feed material are disclosed. The process includes the steps of partially reducing and at least partially melting a metalliferous feed material in a pre-reduction/melting means and completely reducing the partially reduced feed material in a reduction means. The pre-reduction/melting means is positioned directly above the reduction means and communicates with the reduction means so that at least partially molten, partially reduced feed material flows downwardly into a central region of the reduction means. The reduction means includes a vessel that contains a molten bath having a metal layer and a slag layer on the metal layer. The process includes injecting oxygen-containing gas into the reduction means and post-combusting reaction gas generated in the molten bath and injecting oxygen-containing gas into the pre-reduction/melting means and post-combusting reaction gas discharged from the reduction means. The process further includes injecting solid carbonaceous material and a carrier gas into a metal rich region of the molten bath and causing upward movement of splashes, droplets and streams of molten material which forms a transition zone.
Abstract:
A process for direct smelting a metalliferous feed material is disclosed. The process includes the steps of partially reducing metalliferous feed material and subsantially devolatilising coal in a pre-reduction vessel and producing a partially reduced matelliferous feed material and char. The process also includes direct smelting the partially reduced matalliferous feed material to molten metal in a direct smelting vessel using the char as a source of energy and as a reductant and post-combusting reaction gas produced in the direct smetling process with pre-heated air or oxygen-enriched air to a post-combustion level of greater than 70 % to generate heat required for the direct smelting reactions and to maintain the metal in a molten state.