Abstract: Waste plastics including solid plastics, thin plastics, and foamy plastics are fed into a ring die of an extrusion molding machine. The waste plastics are either semi-melted or melted, and are then extruded onto an outer circumferential surface the ring die through die cavities. Thus, granular plastic moldings are extruded onto the outer circumferential surface of the ring die through the die cavities, and are then cut or scraped from the outer circumferential surface of the ring die. The pellets have a melt-solidified surface, and have a strength sufficient to reach a predetermine zone in a raceway of a furnace and a grain diameter sufficient to be fed at a velocity higher than a limiting velocity thereof during injection to the furnace.

Abstract: An apparatus and method for measuring a temperature of a high temperature liquid contained in a furnace. An optical fiber covered with a metallic tube is inserted through a passageway inside a nozzle arranged on a furnace wall of the furnace. The nozzle communicates with an interior of the furnace containing the liquid, and gas is supplied into the passageway inside the nozzle to prevent the nozzle from clogging. The metal-covered optical fiber is fed through the passageway inside the nozzle into the liquid such that spectral light radiated from the liquid enters a tip of the metal-covered optical fiber and is propagated therealong. The temperature of the liquid is determined by a radiation thermometer, coupled to the metal-covered optical fiber, based on the spectral light propagated along the metal-covered optical fiber.

Abstract: A method for controlling a flow rate of gas for prereducing ore comprises the steps of prereducing ore in a prereduction furnace having a fluidized bed with a gas generated in a smelting reduction furnace and controlling a pressure of gas generated in the smelting reduction furnace and introduced into the prereduction furnace, thereby controlling the actual flow rate of gas introduced into the prereduction furnace. An apparatus for controlling a flow rate of gas for prereducing ore comprises a flow passage for introducing gas generated in a smelting reduction furnace into a prereduction furnace and a gas pressure control valve positioned in the flow passage.

Abstract: A prereduction furnace of a smelting reduction facility of iron ore includes of a fluidizing prereduction chamber at an upper part of the prereduction furnace wherein iron ores are fed and prereduced, a gas blowing chamber at a lower part of the prereduction furnace wherein a reducing gas is fed, a ceramic main body of a distributor mounted between the fluidizing prereduction chamber and the gas blowing chamber, a metal box attached to the bottom side of the ceramic main body, which prevent adhesion of dust in the reducing gas, nozzles passing through the ceramic main body and through the metal box for injecting the reducing gas in the blowing chamber, into the prereduction chamber and a discharge pipe for discharging prereduced iron ores mounted at a bottom center portion of the prereduction chamber and extending through the ceramic main body, through the metal box, and through a bottom of the gas blowing chamber.

Abstract: A prereduction furnace of a smelting reduction facility of iron ore includes a fluidizing prereduction chamber installed at an upper part of the prereduction furnace wherein iron ores are fed and prereduced, a gas blowing chamber installed at a lower part of the prereduction furnace wherein a reducing gas is fed, a distributor installed between the fluidizing prereduction chamber and the gas blowing chamber, a first plurality of nozzles passing through the distributor for injecting the reducing gas in the gas blowing chamber into the fluidizing prereduction chamber, a discharge pipe for discharging prereduced iron ores installed at a bottom center portion of the fluidizing prereduction chamber and extending through the distributor, wherein a cooling fluid flows, at least two horizontally movable gas purging pipes arranged below the distributor, and a second plurality of nozzles attached to the horizontally movable gas purging pipes for injecting a purging gas to a bottom surface of the distributor to prevent

Abstract: A prereduction furnace of a smelting reduction facility comprises a fluidizing prereduction chamber in the upper part of the prereduction furnace wherein iron ores are fed and prereduced, a gas blowing chamber installed in the lower part of the prereduction furnace wherein a reducing gas is fed, a distributor for separating the fluidizing prereduction chamber from the gas blowing chamber, and a discharge pipe for discharging the prereduced ore from the fluidizing prereduction chamber. The distributor includes a body of refractory material, a metal plate installed on the bottom of the body, nozzles passing through the body and the metal plate, metallic pipes inserted in the nozzles, and cooling pipes connected to the metal plate. A metallic box may be installed below the metal plate for providing passages for gas flow. A bottom plate may be installed spacedly below the metal plate, with nozzles passing therethrough. The distributor may comprise a rigid thick plate and a refractory layer thereon.