C21B13/02

METHOD FOR RECYCLING SPENT REDUCTION GAS IN A DIRECT REDUCTION OF IRON ORE SYSTEM UTILIZING AN ELECTRIC GAS HEATER
20230052345 · 2023-02-16 ·

A process for producing direct reduced iron with a hydrogen rich gas, utilizing a non-fired reducing gas heater such as an electric heater to heat the reducing gas to the temperatures sufficient for iron reduction, includes: providing a shaft furnace to reduce iron oxide with the hydrogen rich reducing gas; removing steam and particulates from the shaft furnace top gas with a scrubber; processing all or a portion of the scrubbed top gas in a gas separation unit such as a membrane and a PSA gas separation unit to create a hydrogen rich stream to be recycled back to the shaft furnace as the reducing agent, so that the hydrogen consumption can be reduced when non-fired reducing gas heater is applied.

METHOD FOR RECYCLING SPENT REDUCTION GAS IN A DIRECT REDUCTION OF IRON ORE SYSTEM UTILIZING AN ELECTRIC GAS HEATER
20230052345 · 2023-02-16 ·

A process for producing direct reduced iron with a hydrogen rich gas, utilizing a non-fired reducing gas heater such as an electric heater to heat the reducing gas to the temperatures sufficient for iron reduction, includes: providing a shaft furnace to reduce iron oxide with the hydrogen rich reducing gas; removing steam and particulates from the shaft furnace top gas with a scrubber; processing all or a portion of the scrubbed top gas in a gas separation unit such as a membrane and a PSA gas separation unit to create a hydrogen rich stream to be recycled back to the shaft furnace as the reducing agent, so that the hydrogen consumption can be reduced when non-fired reducing gas heater is applied.

FACILITY AND METHOD FOR PRODUCTION OF DIRECT REDUCED IRON
20230038218 · 2023-02-09 · ·

The present disclosure provides a facility to produce direct reduced iron, which makes it possible to perform reforming and reduction and adjust the carbon amount in a product within a wide range without requiring an externally heating reformer and without causing the metal dusting problem in a circulating gas preheater and the problem of sintering each other or fusion between reduced iron, in a furnace. The facility to produce the direct reduced iron according to the present invention is equipped with a water content control device for controlling the water content in a gas discharged from a shaft-type reduction furnace, a first gas mixing device for mixing the gas from which a portion of water has been removed with an oxygen-containing gas and a hydrocarbon-containing gas to produce a mixed gas, and an auto-thermal reformer for reforming the mixed gas with its energy. The facility is also equipped with a cooling gas loop for circulating a cooling gas, wherein the cooling gas has a hydrocarbon concentration of 50% or more, and the cooling gas loop is equipped with a cooling gas after-cooler having a flow rate control function and capable of controlling the temperature of the cooling gas.

Charging system, in particular for a shaft smelt reduction furnace

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.

Charging system, in particular for a shaft smelt reduction furnace

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.

SYSTEM AND METHOD FOR THE PRODUCTION OF HOT BRIQUETTED IRON (HBI) CONTAINING FLUX AND/OR CARBONACEOUS MATERIAL AT A DIRECT REDUCTION PLANT
20220403481 · 2022-12-22 ·

A process for producing hot briquetted iron with increased solid carbonaceous material and/or flux includes: providing a shaft furnace of a direct reduction plant to reduce iron oxide with reducing gas; providing a hot briquette machine to produce hot briquetted iron; coupling a chute between a) a discharge exit of the shaft furnace for discharge of hot direct reduced iron and b) an entrance of the hot briquette machine; adding solid carbonaceous material and/or flux to the discharged hot direct reduced iron from the shaft furnace to produce a mixture of the discharged hot direct reduced iron and the solid carbonaceous material and/or flux before feeding to the hot briquette machine; and processing in the hot briquette machine to produce a product of hot briquetted iron with increased solid carbonaceous material content greater than about 3 weight percent and/or an increased flux content.

METHOD AND CORRESPONDING APPARATUS FOR PRODUCING IRON FROM DIRECT REDUCTION OF IRON ORE

A method for producing direct reduced iron is provided. The method includes circulating a first stream of spent reducing gas exiting a reactor in a reducing gas circuit through at least one carbon dioxide removal unit and a reducing gas heater and the reactor. The method also includes mixing the first stream with reducing gas containing heavier hydrocarbons than methane.

METHOD AND CORRESPONDING APPARATUS FOR PRODUCING IRON FROM DIRECT REDUCTION OF IRON ORE

A method for producing direct reduced iron is provided. The method includes circulating a first stream of spent reducing gas exiting a reactor in a reducing gas circuit through at least one carbon dioxide removal unit and a reducing gas heater and the reactor. The method also includes mixing the first stream with reducing gas containing heavier hydrocarbons than methane.

METHOD FOR THE DIRECT REDUCTION OF IRON ORE

The invention relates to a process for direct reduction of iron ore to afford direct reduced iron, wherein the iron ore sequentially passes through a reduction zone for reducing the iron ore to direct reduced iron and a cooling zone for cooling the direct reduced iron, wherein in the reduction zone the iron ore is subjected to a flow of a reduction gas and wherein in the cooling zone the direct reduced iron is subjected to a flow of a cooling gas. The cooling gas in the cooling zone comprises H2 and CO2, wherein the ratio of the mole fractions of H2 to CO2 is greater than 1.8 and the mole fraction of CO2 is greater than 20 mol %.

Direct reduction process utilizing hydrogen

A process for the production of direct reduced iron (DRI), with or without carbon, using hydrogen, where the hydrogen is produced utilizing water generated internally from the process. The process is characterized by containing either one or two gas loops, one for affecting the reduction of the oxide and another for affecting the carburization of the DRI. The primary loop responsible for reduction recirculates used gas from the shaft furnace in a loop including a dry dedusting step, an oxygen removal step to generate the hydrogen, and a connection to the shaft furnace for reduction. In the absence of a second loop, this loop, in conjunction with natural gas addition, can be used to deposit carbon. A secondary carburizing loop installed downstream of the shaft furnace can more finely control carbon addition. This loop includes a reactor vessel, a dedusting step, and a gas separation unit.