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 of the space 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 a 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 upwards 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 (29, 49) 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:
A steelmaking process is disclosed. The process includes producing molten steel and molten steelmaking slag in a steelmaking process, the steelmaking slag including iron units and flux units, and thereafter producing molten iron in a molten bath based direct smelting process using a substantial portion of the steelmaking slag as part of the feed material requirements for the direct smelting process. A direct smelting process is also disclosed. The process includes pre-treating ferrous material including steelmaking slag and thereafter direct smelting molten iron using the pretreated ferrous material as part of the feed material for the process.
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 characterised 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 characterised 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 reactor for aerating a fluid with a gas comprises a mixing tank (12) for the fluid and a centrally located vertical draft tube (13) submerged in the fluid to divide the mixing tank (12) into an inner chamber (21) and an outer chamber (23). The reactor further comprises a motor driven axial flow impeller (14) located in the draft tube (13) for circulating fluid downwardly through the inner chamber (21) and upwardly through the outer chamber (23). The reactor further comprises an external circuit for withdrawing a portion of the fluid from the mixing tank (12), aerating the fluid, and returning the aerated fluid to the mixing tank (12). The aerator is in the form of a venturi device (17).
Abstract:
A method of separating potassium chloride and sodium chloride from a heated solution of these salts, such as a solution obtained from potash ore, to recover potassium chloride from the ore is disclosed. The method includes a combination of steps of (a) extracting water from a heated solution containing potassium chloride and sodium chloride using a membrane system and (b) subsequently cooling the solution discharged from the membrane system, whereby steps (a) and (b) make it possible to selectively recover potassium chloride and sodium chloride from the solution.
Abstract:
Un método para separar cloruro de potasio y cloruro de sodio a partir de una solución calentada de estas sales, como por ejemplo una solución obtenida a partir de mineral de potasa, para recuperar cloruro de potasio del yacimiento. El método incluye una combinación de los pasos siguientes: (a) extraer agua de una solución calentada, que contiene cloruro de potasio y cloruro de sodio, utilizando un sistema de membrana; y (b) enfriar posteriormente la solución descargada del sistema de membrana, por lo cual los pasos (a) y (b) hacen posible recuperar selectivamente cloruro de potasio y cloruro de sodio a partir de la solución.