Provided is a method for manufacturing reduced iron which includes the steps of: i) drying ores in an ore drier; ii) supplying the dried ores to at least one reduction reactor; iii) reducing the ores in the at least one reduction reactor and manufacturing reduced iron; iv) discharging exhaust gas by which the ores are reduced in the reduction reactor; v) branching the exhaust gas and providing the branched exhaust gas as ore feeding gas; and vi) exchanging heat between the exhaust gas and the ore feeding gas and transferring the sensible heat of the exhaust gas to the ore feeding gas. In the supplying the dried ores to the at least one reduction reactor, the dried ores are supplied to the at least one reduction reactor by using the ore feeding gas.

A process for the production of sponge iron and a system for the production of sponge iron. The process includes the steps of: producing electrolytic hydrogen and oxygen by electrolysis of water; producing methanol by reacting the electrolytic hydrogen with carbon dioxide; storing the methanol; reforming the methanol using water and/or oxygen to provide carbon dioxide and released hydrogen; providing the released hydrogen as a component portion of a reducing gas to a direct reduction shaft; and reducing iron ore in the direct reduction shaft using the reducing gas to produce the sponge iron.

A method for producing reduced iron that produces reduced iron by reducing iron oxide charged in a shaft furnace, in which a gas mixture which contains a reducing gas and a nitrogen gas, and has a predetermined temperature, is blown into the shaft furnace. The reducing gas contains 90 volume% or more of a hydrogen gas.

A method for producing reduced iron that produces reduced iron by reducing iron oxide charged in a shaft furnace, in which a heated gas mixture which contains a reducing gas and a nitrogen gas, the reducing gas containing 90 volume % or more of a hydrogen gas, is blown into the shaft furnace from a tuyere equipped at a lower portion of a reduction zone of the shaft furnace, at least part of the reducing gas is blown into a cooling zone of the reduced iron provided at a lower portion of the shaft furnace at normal temperature, and the reducing gas that has flowed up in the cooling zone is used for reduction of the iron oxide.

Provided is an apparatus for manufacturing reduced iron and a method for manufacturing reduced iron. The method for manufacturing reduced iron includes the steps of: i) drying ores in an ore drier; ii) supplying the dried ores to at least one reduction reactor; iii) reducing the ores in the at least one reduction reactor and manufacturing reduced iron; iv) discharging exhaust gas by which the ores are reduced in the reduction reactor; v) branching the exhaust gas and providing the branched exhaust gas as ore feeding gas; and vi) exchanging heat between the exhaust gas and the ore feeding gas and transferring the sensible heat of the exhaust gas to the ore feeding gas. In the steps of supplying the dried ores to the at least one reduction reactor, the dried ores are supplied to the at least one reduction reactor by using the ore feeding gas.

A method of operating an ironmaking or steelmaking plant with low CO.sub.2-emissions is provided. Hydrogen and oxygen are generated by water decomposition and at least part of the generated hydrogen is injected as a reducing gas into one or more ironmaking furnaces with off-gas decarbonation and reinjection into the furnaces of at least a significant part of the decarbonated off-gas and at least part of the generated oxygen is injected as an oxidizing gas in the one or more ironmaking.

A direct reduction system and process for reducing a metal oxide to a metal, including and utilizing: a process gas line configured to deliver a portion of a process gas to a reformer operable for reforming the process gas to form a reformed gas; a bustle gas line configured to deliver the reformed gas to a shaft furnace as a bustle gas, wherein the shaft furnace is operable for reducing the metal oxide to the metal; and a direct recycle line including a direct recycle cooler configured to selectively deliver a portion of the process gas to the bustle gas line while circumventing the reformer, thereby selectively cooling and lowering the moisture content of the bustle gas delivered to the shaft furnace. Optionally, the direct reduction system further includes a reheat line configured to deliver a portion of the bustle gas to the shaft furnace as reheat gas.

A classified reduction gasification iron smelting process of iron ore powder and coal powder in a Y-type entrained flow bed. The process comprises the following steps: uniformly mixing the pre-reduced hot iron ore powder with the coal powder, and introducing the mixture, a gasification agent and water vapor into a Y-type entrained flow bed for performing combustion, gasification and reduction reaction to obtain crude syngas and molten iron; the crude syngas is used for sucking iron ore powder to enter a riser to perform preheating and partial reduction.

The invention relates to the use of off-gas from furnaces (2) for the process of reduction of iron oxide. The bypass duct leads off-gas with reduction atmosphere directly into the reactor, passing through and back to join the main duct of dedusting system using negative pressure of the primary dedusting system. The off-gas directly heats up the iron oxide pellet and maintain the reduction atmosphere in the reactor and allow the reaction to proceed and prevent re-oxidation.

A method of operating an ironmaking or steelmaking plant with low CO.sub.2-emissions is provided. Hydrogen and oxygen are generated by water decomposition and at least part of the generated hydrogen is injected as a reducing gas into one or more ironmaking furnaces with off-gas decarbonation and reinjection into the furnaces of at least a significant part of the decarbonated off-gas and at least part of the generated oxygen is injected as an oxidizing gas in the one or more ironmaking.