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.

The invention relates to a blast furnace plant (1, 1a-1c) with a blast furnace (2) and a charging device (3) for the blast furnace (2). In order to provide an economical way of providing clean gas to the charging device, the invention provides that the blast furnace plant (1, 1a-1c) further comprises: at least one nozzle (6) for introducing a clean gas into said charging device (3); a cleaning device (7) which is connected for receiving gas from the blast furnace (2) and arranged for removing dust from the gas; at least one compressor (9) arranged for receiving gas from the cleaning device (7), compressing the gas and feeding the gas to the at least one nozzle (6); and at least one turbine (8) connected for receiving and being driven by gas from the blast furnace (2), the at least one turbine being mechanically coupled to drive the at least one compressor (9).

A system for reducing ore includes a hydrogen supply unit configured to supply hydrogen, a furnace configured to reduce the ore using the supplied hydrogen, and a hydrogen recovery unit configured to recover hydrogen from an exhaust gas that is exhausted from the furnace.

A method for operating a blast furnace for producing of pig iron, includes the following steps heating a first stream of steam in a first heater, before or after having been mixed with an oxygen source selected from oxygen and oxygen-enriched air, to provide a first heated stream of oxygen-enriched steam; heating a first stream of blast furnace gas from the blast furnace and a first stream of natural gas in a second heater, before or after being mixed together, to provide a heated carbon feed stream; feeding the first heated stream of oxygen-enriched steam and the heated carbon feed stream either as a combined stream or separately to a catalytic partial oxidation reactor to produce a stream of syngas; and feeding the stream of syngas to the shaft of the blast furnace.

A plant complex for producing steel, having a blast furnace for producing pig iron; a converter steel works for producing crude steel; a gas pipeline system for gases that occur in the production of pig iron and/or the production of crude steel; a chemical plant and/or a biotechnology plant which are/is connected to the gas pipeline system, wherein the plant complex additionally includes a biogas plant which is connected to the gas pipeline system.

A plant complex for pig iron production may include a furnace and a furnace gas conduit system for a furnace gas quantity stream that comprises nitrogen, carbon monoxide, and carbon dioxide. The plant complex may also include a hydrogen source, an H.sub.2 gas conduit system for a hydrogen-containing gas quantity stream emitted from the hydrogen source, a mixing apparatus for establishing a mixed gas formed from the furnace gas stream and the hydrogen-containing gas quantity stream. The mixing apparatus may be connected to the furnace gas conduit system and to the H.sub.2 gas conduit system. The mixed gas established may have a stoichiometric mixing quotient formed from a dividend with a difference value between molar amounts of hydrogen as minuend and carbon dioxide as subtrahend and of a divisor with a sum value of molar amounts of carbon monoxide and carbon dioxide. The plant complex may also include a mixed gas conduit system and a chemical plant connected to the mixed gas conduit system.

A charging system for a shaft smelt reduction furnace includes a frame structure for mounting on a top charge opening of a shaft smelt reduction vessel; a center shaft arrangement supported by the frame structure and for removing off-gas gases from the furnace and to introduce granular charge materials to form a stack of materials in the furnace. The center shaft arrangement includes a center hood for off-gas extraction; a pair of first and second feed channels for first and second materials. The center hood includes a pair of facing off-gas panels defining an off-gas channel. The partition walls include lower portions that extend towards each other below the center hood to define a center feed passage, whereby material descending through the first feed channels may accumulate on lower portions according to the angle of repose of the material, permitting self-adjustment of the first material stock-line in the shaft arrangement.

The invention relates to a plant complex for steel production comprising a blast furnace for producing pig iron, a converter steel mill for producing crude steel and a gas-conducting system for gases that occur when producing the pig iron and/or producing the crude steel. According to the invention, the plant complex additionally has a chemical plant or biotechnological plant, connected to the gas-conducting system, and also energy storage for covering at least part of the electricity demand of the plant complex. Also the subject of the invention is a method for operating the plant complex.

The invention relates to a plant complex for steel production comprising a blast furnace for producing pig iron, a converter steel mill for producing crude steel, a gas-conducting system for gases that occur when producing the pig iron and/or the crude steel, and a power-generating plant for electricity generation. The power-generating plant is designed as a gas-turbine power-generating plant or gas-turbine and steam-turbine power-generating plant and is operated with a gas that comprises at least a partial amount of the blast-furnace top gas that occurs in the blast furnace and/or a partial amount of the converter gas. The plant complex additionally comprises a chemical plant and a biotechnological plant, the power-generating plant, the chemical plant and the biotechnological plant being arranged in a parallel setup with regard to the gas supply. The gas-conducting system comprises an operationally controllable gas-distributing device for dividing the streams of gas.

The invention relates to a method for producing syngas in combined operation with a metallurgical plant which comprises at least one blast furnace for producing crude iron, a converter steel mill and a coke-oven plant. Part of the blast-furnace top gas that is produced in the production of crude iron and/or part of the converter gas that occurs in the converter steel mill and/or part of the coke-oven gas that is produced in the coke-oven plant are mixed. By choosing the gas streams that are brought together to form a mixed gas and/or by changing the mixing ratios of the gas streams that are brought together, at least two streams of useful gas are produced, differing with regard to their composition and respectively prepared to form streams of syngas.