The invention relates to a method for the direct reduction of oxidic iron carrier particles to a reduction product in a fluidized bed through which a reduction gas containing 30-100 mol % hydrogen H.sub.2 flows in crossflow. At least 90% by mass of oxidic iron carrier particles introduced into the fluidized bed have a particle size of less than or equal to 200 micrometers. The superficial velocity U of the reduction gas flowing through the fluidized bed is set between 0.05 m/s and 1 m/s such that, for the particle size d equal to d.sub.30 of the oxidic iron carrier particles introduced into the fluidized bed, it is above the theoretical suspension velocity U.sub.t and is less than or equal to U.sub.max.

A method for producing a homogenous molten composition and a fluid product is disclosed. For example, the method includes producing a first molten metal composition in an enclosed volume, contacting a hydrocarbon reactant with the first molten metal composition, decomposing the hydrocarbon reactant into at least one fluid product and carbon, forming a metal alloy from a mixture of the carbon and the first molten metal composition, and separating a homogenous second molten composition from the metal alloy.

A method and system for operating a seal gas compressor utilized in a direct reduction process including: monitoring a pH level of a water stream used in the seal gas compressor, wherein the pH level of the water stream is affected by a reformer flue gas stream that comes into contact with the water stream, wherein the monitoring step is carried out one or more of upstream of the seal gas compressor and downstream of the compressor; and adjusting the pH level of the water stream to maintain the pH level of the water stream within a predetermined range based on feedback from the monitoring step. The method includes maintaining the pH level of the water stream upstream of the seal gas compressor in a range between 7.5 and 10 and maintaining the pH level of the water stream downstream of the seal gas compressor in a range between 7.8 and 9.5.

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.

Provided is a steelmaking line contributing to the realization of a method that achieves energy saving and CO.sub.2 emission reduction when producing reduced iron from iron oxide. The steelmaking line comprises: a blast furnace configured to reduce iron oxide; a reducing furnace configured to reduce iron oxide; a methane synthesizer configured to synthesize methane from blast furnace gas and/or furnace top gas, and hydrogen gas; a blower configured to blow the methane gas synthesized by the methane synthesizer into the blast furnace; a heat-reformer configured to heat or heat-reform the blast furnace gas and/or the furnace top gas, and the methane gas synthesized by the methane synthesizer, to generate reducing gas; a reducing gas blower configured to blow the reducing gas into the reducing furnace; and a supply path configured to supply the furnace top gas to the methane synthesizer and/or the heat-reformer.

Systems for producing iron may include (a) a reactor configured to receive iron ore and a reducing gas, and from these produce iron; and (b) a carbon dioxide reduction electrolyzer configured to produce at least carbon monoxide and/or a hydrocarbon. Such systems may be configured to transport carbon dioxide produced by the reactor and/or produced by combustion of a gas generated by the reactor to a cathode side of the carbon dioxide reduction electrolyzer. Such systems may be further configured to transport at least a portion of the carbon monoxide and/or hydrocarbon produced by the carbon dioxide reduction electrolyzer to the reactor, where the carbon monoxide and/or hydrocarbon serves as at least a part of the reducing gas.

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.

In a process and apparatus for the reduction of metal oxides to form metalized material by contact with hot reducing gas, which is produced at least partially by catalytic reformation of a mixture of—a gas containing carbon dioxide (CO.sub.2) and/or steam (H.sub.2O) with—gaseous hydrocarbons, the fuel gas for burners which provide the heat for the endothermal reformation processes which take place during the reformation is obtained at least partially from a partial quantity of the top gas produced during the reduction of metal oxides to form metalized material, wherein this partial quantity of the top gas, before it is used as a component of the fuel gas, is firstly subjected to dedusting and then to a CO conversion reaction, and the conversion gas obtained during the CO conversion reaction is subjected to CO.sub.2 removal after cooling.

A method for producing steel in which iron ore is reduced with hydrogen and the resulting intermediate product of reduced iron ore is subjected to further metallurgical processing; the hydrogen is produced through electrolysis of water; the electrical energy required for the electrolysis is regenerative energy from hydroelectric, wind, and/or photovoltaic sources and the hydrogen and/or the intermediate product is produced regardless of demand, whenever enough regeneratively produced electrical energy is available; and unneeded intermediate product is stored until there is demand or it is used so that the regenerative energy that is stored therein is also stored; and using a calculation model to calculate a required discharge rate in a reduction shaft to achieve a desired metallization grade of the steel by tracing batches of the iron ore in the reduction shaft, and using the calculation model to calculate the amount of carbon-containing gas or hydrogen-containing gas to add to the hydrogen for the reduction.