Abstract: Method of constructing and installing a direct smelting unit comprising a smelting vessel (11). The vessel is prefabricated off site in three modules (11A, 11B, 11C) which are then transported to the installation site where they are hoisted by a crane and deposited sequentially on top of one another and joined together by welding to form a unitary vessel. The vessel modules are prefabricated so as to be internally lined with water cooling panels connected to water inlet and outlet connectors (62) on the exterior of the circumferential wall sections of those modules. A vessel access tower is formed in modules brought together to envelop the tower and carrying water supply and return piping which is connected to the water inlet and outlet connectors (62) of the cooling panels.

Abstract: A gravity gradiometer is disclosed which has a sensor in the form of bars (41 and 42) which are supported on a mounting (5) which has a first mount section (10) and a second mount section (20). A first flexure web (33) pivotally couples the first and second mount sections about a first axis. The second mount has a first part (25), a second part (26) and a third part (27). The parts (25 and 26) are connected by a second flexure web (37) and the parts (26 and 27) are connected by a third flexure web (35). The bars (41 and 42) are located in housings (45 and 47) and form a monolithic structure with the housings (45 and 47) respectively. The housings (45 and 47) are connected to opposite sides of the second mount section 20. The bars (41 and 42) are connected to their respective housings by flexure webs (59). Transducers (71) are located in proximity to the bars for detecting movement of the bars to in turn enable the gravitational gradient tensor to be measured.

Abstract: The present invention provides a method of tuning properties of a gravity gradiometer for measuring components of the gravity gradient tensor. The gravity gradiometer comprises a pair of first and second transversely arranged sensor masses that are arranged for movement about an axis and relative to each other in response to a gravity gradient. The gravity gradiometer further comprises first and second capacitors for sensing and influencing the movement of the first and second sensor masses. The method comprising applying a bias voltage to at least one of the capacitors for generating an electrostatic force which acts on one of the sensor masses and thereby influences the movement of that sensor mass.

Abstract: The present invention provides a gravity gradiometer for measuring components of the gravity gradient tensor. The gravity gradiometer comprises at least one sensor mass for movement in response to a gravity gradient and a sensor and actuator unit for generating an electrical signal in response to the movement of the at least one sensor mass and for influencing the movement of the at least one sensor mass. The gravity gradiometer also comprises an electronic circuit for simulating an impedance. The electrical circuit is arranged for amplifying the electrical signal received from the sensor and actuator unit and for directing an actuating signal to the sensor and actuator unit. The electronic circuit comprises a differential amplifiers having first and second amplifier input terminals and an amplifier output terminal and impedances Z1, Z2, Z3, at least one of the impedances have an imaginary impedance component.

Abstract: The present invention provides a gravity gradiometer for measuring components of the gravity gradient tensor. The gravity gradiometer comprises a housing and a gimballed support structure with at least one actuator. The gravity gradiometer further comprises at least one sensor mass arranged for movement in response to a gravity gradient. The gravity gradiometer also comprises a transducer that is arranged so that the movement of the at least one sensor mass relative to a portion of the transducer generates a transducer signal. Further, the gravity gradiometer comprises an electrical feedback loop arranged to direct an electrical signal to the actuator of the external support structure. The gravity gradiometer is arranged so that an influence of an external angular acceleration on the rotation of the housing is reduced by the actuator when the transducer generates a transducer signal effected by the external angular acceleration on the gravity gradiometer.

Abstract: The present invention provides a gravity gradiometer for measuring components of the gravity gradient tensor. The gravity gradiometer comprises at least one sensor mass for movement in response to a gravity gradient and a pivotal coupling enabling the movement of the at least one sensor mass about an axis. Further, the gravity gradiometer comprises a constant charge capacitor that is arranged so that the movement of the at least one sensor mass generates a change in a voltage across the constant charge capacitor.

Abstract: The present invention provides a gravity gradiometer for measuring components of the gravity gradient tensor. The gravity gradiometer comprises at least one sensor mass for movement in response to a gravity gradient. The gravity gradiometer also comprises a pivotal coupling enabling the movement of the at least one sensor mass about an axis. Further, the gravity gradiometer comprises a plurality of capacitors. Each capacitor has first and second capacitor elements positioned opposite each other so that a gap is defined between respective first and second capacitor elements. The capacitors are arranged so that movement of the at least one sensor mass results in a change in the gap between respective first and second capacitor elements. At least one of the capacitor elements has at least two separate capacitor portions arranged so that separate voltages can be applied to the capacitor portions.

Abstract: The present invention provides a gravity gradiometer which comprises at least one sensor mass suspended by a coupling which enables movement of the at least one sensor mass about an axis in response to a gravity gradient. Further, the gravity gradiometer comprises at least one transducer for generating an electrical signal in response to the movement of the at least one sensor mass relative to a component of the transducer and for influencing the movement of the at least one sensor mass. The gravity gradiometer also comprises electrical circuitry for receiving the electrical signal from the at least one transducer and for directing an actuating signal to the at least one transducer so that in use the at least one transducer functions as sensor and actuator.

Abstract: A metallurgical vessel having a cylindrical upper end section and a top section fitted to the upper end of another section to form a top closure of the vessel about a central opening through which to extend a gas injection lance for injecting gas into the vessel. Top section is formed as a two-part domed construction comprising an outer annular panel welded to the vessel top section and an inner annular panel removably fastened to outer panel, both panels being formed with inwardly concave curvature so as to form together the continuously domed top section. The two panels are fastened together by clamping bolts extended through outturned flanges formed on annular flanges standing up from the panels. On release of bolts panel is removable to provide access to the interior of the vessel.

Abstract: Metallurgical processing installation comprising a metallurgical vessel lined internally with water cooled panels. A vessel access tower (61) fits around vessel (11) and supports a coolant flow system (62) to provide for flow of cooling water to and from the cooling panels within the vessel through water inlet and outlet connections (42,43) distributed around the exterior of the vessel. Coolant flow system (62) includes large diameter water supply and return pipes (66,67) mounted on an upper part of the tower (61) to extend around the upper end of vessel (11), a first series of vertical dropper pipes (68) of relatively small diameter connected to the main water supply pipe 66 and extending downwardly to connections with the water inlet connectors for respecting cooling panels of the vessel and a second series of smaller diameter vertical pipes (69) connected at their upper ends to the main return pipe (67) and at their lower ends to undivided outlet connectors for the cooling panels in the vessel.

Abstract: A roll crusher assembly for use in the mining industry is disclosed. The assembly includes one or more than one roll (3) for crushing a feed material. The roll or rolls has an outer surface that is formed from a wear resistant material. The assembly also includes a means, such as a welding assembly (13), for depositing a hard facing material onto the surface of the roll or rolls as the roll or rolls rotate during a crushing operation.

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 process for producing desulphurised iron in a solid form is disclosed. The process includes the steps of (a) direct smelting an iron-containing metalliferous feed material and producing molten iron; (b) desulphurising molten iron produced in direct smelting step (a); and (c) casting desulphurised molten iron from desulphurisation step (b) into a solid form, such as pigs.

Abstract: A direct smelting plant that includes an effective and reliable solids feed means for injecting solid feed materials, particularly carbonaceous material, into a direct smelting vessel of the plant is disclosed. The solid feed means is characterised by independent supply of carbonaceous material to injection lances. The independent supply of carbonaceous material minimises the possible adverse impact of a a breakdown of one or more than one lance or a breakdown of the carbonaceous material injection means for that lance or lances.

Abstract: A method and an apparatus for analyzing a material, such as coal and iron ore, particularly with a view to identifying contaminants, is disclosed. The method and apparatus are based on the use of multiple (particularly dual) energy x-ray analysis with x-rays at different photon energies. X-rays are transmitted through a material and the detected x-rays are processed to produce an image of the material that combines together the separated images produced by the different photon energy x-rays. The combined image has enhanced contrast which minimizes the affects of non-compositional factors that otherwise would affect identifying constituents of the material.

Abstract: A method and an apparatus for producing metals and metal alloys from metal oxides in a metallurgical vessel containing a molten bath having a metal layer and a slag layer is disclosed. The method is characterized by injecting a carrier gas and a solid carbonaceous material and/or metal oxides into the molten bath from a side of the vessel that is in contact with the molten bath or from above the molten bath so that the solids penetrate the molten bath and cause molten metal to be projected into the gas space above the molten bath to form a transition zone. The method is also characterized by injecting an oxygen-containing gas into the gas space to post-combust reaction gases released from the molten bath into the transition zone.

Abstract: A method of treating inorganic solid waste in a bath of molten metal contained in a vessel (3) which has a space above the bath and a waste gas outlet (11) is disclosed. The method comprises injecting waste into the bath to form a primary reaction zone (13) in which there are reactions between the waste and the bath or in which the waste undergoes a change of phase to convert the waste into more readily recoverable or disposable products. The method further comprises injecting oxygen-containing gas towards the surface of the bath to form a secondary reaction zone (17) in a section above the bath through which oxidisable products released from the primary reaction zone (13) flow to reach the waste gas outlet (11) in the vessel (3) and in which the oxidisable products are oxidised and the heat released by such oxidation is transferred into the bath.

Abstract: A reactor for introducing gas into a fluid comprises a mixing tank (12, 43) for the fluid and a partition means (13,45) for dividing the tank into at least two chambers (21, 89) and (23, 91). The reactor further comprises a first pump means (14, 47) located in one of the chambers for circulating the fluid downwards in one chamber and then upward in the other chamber and an aerator assembly (29, 49) for aerating a sidestream of the fluid and introducing the aerated fluid into the tank for mixing the aerated fluid with the circulating fluid in the tank. The aerator assembly comprises a bank of venturi aerators (38, 57) each having an aerator inlet; an aerator outlet; and a constriction intermediate the aerator inlet and the aerator outlet for creating a region of reduced pressure in the fluid, the constriction being elongate in a section transverse to the direction of flow of the fluid through the constriction; and a means for introducing the gas into the constriction to aerate the fluid.

Abstract: The invention relates to a method for intensifying the reactions in metallurgical reaction vessels containing a molten bath to which the reacting agents are fed below and above the bath surface, the gases emerging from the metal bath being afterburned in the space above the smelt by oxidizing gases injected into said gas space and the resulting heat being transferred to the molten bath, whereby fractions of the smelt in the form of drops, splashes and large particles of the smelt move on ballistic trajectories within the gas space of said metallurgical reaction vessel, being ejected from the smelt like a fountain through the amount of gas introduced via underbath tuyeres.

Abstract: The invention relates to a method for protecting the refractory lining of a metallurgical reaction vessel containing a smelt consisting of metal and slag, the reacting agents for the smelt being fed to the metal bath through introducing means disposed below and above the bath surface, and the gases escaping from the smelt being afterburned with oxidizing agents in the gas space, i.e. in the space above the still smelt, whereby gaseous reacting agents and/or gases acting inertly in the metal bath are fed to the smelt below the bath surface, and the total refractory lining surface in the gas space of the metallurgical reaction vessel is wetted by partial amounts of smelt in the form of drops, splashes, liquid portions rising or ejected eruptively and like a fountain and/or by wave or sloshing motion of the smelt.