Abstract: A method for operating a smelting furnace installation, in particular a blast furnace installation, includes the following steps: feeding coke, iron oxide containing material and if required fluxing agents to the top of the smelting furnace; injecting a first reducing gas containing hydrogen at a tuyere level of the smelting furnace at a temperature above 1600° C.; injecting oxygen at the tuyere level of the smelting furnace; and injecting a second reducing gas at a lower shaft level of the smelting furnace. Coke is fed at a lump coke rate below 220 kg/t HM and wherein the rate of oxygen injected at the tuyere level is below 120 Nm3/t HM.

Abstract: An iron ore reducing and melting apparatus includes a furnace including from bottom to top: a hearth, a tuyere level, a shaft level and a top level, the blast furnace including at least one first gas injector on the tuyere level, at least one first reducing gas generator connected to the at least one first gas injector, wherein the apparatus is adapted to provide reducing gas including 30-100% (vol/vol) hydrogen on the tuyere level and to operate at a coke rate of below 200 kg/t hot metal.

Abstract: A method for operating a smelting furnace installation, in particular a blast furnace installation, the method including the following steps: feeding coke, iron oxide containing material and if required fluxing agents to the top of the smelting furnace; injecting a first reducing gas containing hydrogen at a tuyere level of the smelting furnace at a temperature above 1600° C.; and injecting a second reducing gas at a lower shaft level of the smelting furnace. The coke is fed at a lump coke rate below 220 kg/t HM, and the density of the first reducing gas is below 0.80 kg/Nm3.

Abstract: A method for operating a blast furnace plant having a blast furnace and an ammonia reforming plant, the method including the steps of feeding a stream of ammonia to the ammonia reforming plant, cracking the stream of ammonia in the ammonia reforming plant to produce a reducing gas, feeding an iron oxide containing charge and the reducing gas into the blast furnace, and reducing iron oxide inside the blast furnace by reaction between the iron oxide containing charge and the reducing gas, where the reducing gas comprises less than 15% of ammonia.

Abstract: A method can be used to burn and cool material in a parallel flow-counter flow regenerative shaft kiln having two shafts that are operated alternately as a burning shaft and a regenerative shaft. The material flows through a preheating zone, a burning zone, and a cooling zone to a material outlet. Fuel is supplied in or above the preheating zone, and thus fuel is heated in the preheating zone prior to entering the burning zone. Further, a parallel flow-counter flow regenerative shaft kiln for burning and cooling material may have two shafts that can be operated alternately as a burning shaft and a regenerative shaft. Each shaft has, in a flow direction, a preheating zone for preheating material, a burning zone for burning material, and a cooling zone for cooling material. A fuel inlet that admits fuel into each shaft is arranged above or inside the preheating zone.

Abstract: A process for recycling blast furnace gas is provided. At least one portion of the gases resulting from the blast furnace undergo a CO2 purification step to create a CO-rich gas which is reinjected at a first top injection point at a temperature between 700° C. and 1000° C. through a top injection line, and at a second bottom injection point at a temperature between 1000° C. and 1300° C. through a bottom injection line. The gases from the bottom and top injection lines are heated at a temperature between 1000° C. and 1300° C. A portion of the CO-rich gas exiting the purification step is directly introduced into the top injection line via a cold gas injection line to obtain a temperature between 700° C. and 1000° C. at the first top injection point. The gas that flows through the bottom and top injection points controlled upstream of the system of the heaters. A device is also provided.

Abstract: The invention mainly relates to a process for recycling blast furnace gas in which at least one portion of the gases resulting from the blast furnace undergo a CO2 purification step so as to create a CO-rich gas which is reinjected at a first top injection point located above the base of the blast furnace at a temperature between 700° C. and 1000° C. through a top injection line, and at a second bottom injection point at the base of the blast furnace at a temperature between 1000° C. and 1300° C. through a bottom injection line, in which the gases from the bottom and top injection lines are heated by means of heaters from which the gases emerge at a temperature between 1000° C. and 1300° C. The process of the invention is essentially characterized in that a portion of the CO-rich gas (18) exiting the purification step is directly introduced into the top injection line (21) via a cold gas injection line (35) in order to obtain a temperature between 700° C. and 1000° C.