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 method for producing direct reduced iron having increased carbon content, comprising: providing a carbon monoxide-rich gas stream; and delivering the carbon-monoxide-rich gas stream to a direct reduction furnace and exposing partially or completely reduced iron oxide to the carbon monoxide-rich gas stream. The carbon monoxide-rich gas stream is delivered to one or more of a transition zone and a cooling zone of the direct reduction furnace. Optionally, providing the carbon monoxide-rich gas stream comprises initially providing one of a reformed gas stream from a reformer and a syngas stream from a syngas source. Optionally, the carbon monoxide-rich gas stream is derived from a carbon monoxide recovery unit that forms the carbon monoxide-rich gas stream and an effluent gas stream. Optionally, the method still further includes providing a hydrocarbon-rich gas stream to one or more of a transition zone and a cooling zone of the direct reduction furnace.

The disclosure relates to a process for the production of sponge iron from iron ore that includes the steps: charging iron ore into a direct reduction shaft; introducing a hydrogen-rich reducing gas into the direct reduction shaft in order to reduce the iron ore and produce sponge iron; removing a top gas from the direct reduction shaft; dividing the top gas into a recycle stream and a bleed-off stream; processing the bleed-off stream through a separation unit to provide a hydrogen-enriched off-stream and an inert-enriched off-stream; and introducing the recycle stream and the hydrogen-enriched off-stream as constituent parts of the hydrogen-rich reducing gas to the direct reduction shaft. The disclosure further relates to a system for the production of sponge iron.

A direct reduction method/system, including: adding variable amounts of natural gas, hydrogen, and a carbon-free oxidizing gas to a feed gas stream upstream of a reformer; reforming the feed gas stream in the reformer to form a reformed gas stream, and delivering the reformed gas stream to a shaft furnace, where the reformed gas stream is used to reduce a metallic ore material to a direct reduced metallic material. The feed gas stream includes a top gas stream recycled from the shaft furnace. Optionally, the carbon-free oxidizing gas includes steam and the method further includes controlling a steam flow rate of the steam to maintain a maximum k-factor value of the feed gas stream of 0.74 or lower. Optionally, the variable amount of hydrogen is selected to replace 20-90% of the natural gas by fuel value. The variable amount of hydrogen is selected based upon an available supply of hydrogen.

A process for reducing metal ore may include: carrying out a reaction between a stream of carbon dioxide and a stream of at least one hydrocarbon, at pressure greater than or equal to 0.5 atmospheres (atm) and less than or equal to 100 atm and at temperature greater than or equal to 800 C. and less than or equal to 1,350 C., to produce a reducing gaseous stream comprising at least H.sub.2, CO, CO.sub.2, and water vapor; and/or reducing at least one metal ore using the reducing gaseous stream so as to obtain at least one reduced metal material and at least one exhausted gaseous stream comprising at least CO.sub.2 and water vapor.

Methods and systems for producing direct reduced iron having increased carbon content, comprising: providing a reformed gas stream from a reformer; delivering the reformed gas stream to a carbon monoxide recovery unit to form a carbon monoxide-rich gas stream and a hydrogen-rich gas stream; and delivering the carbon-monoxide-rich gas stream to a direct reduction furnace and exposing partially or completely reduced iron oxide to the carbon monoxide-rich gas stream to increase the carbon content of resulting direct reduced iron. The carbon monoxide-rich gas stream is delivered to one of a transition zone and a cooling zone of the direct reduction furnace. Optionally, the method further comprises mixing the carbon monoxide-rich gas stream with a hydrocarbon-rich gas stream.

A process for processing metal ore includes: reducing a metal ore, particularly a metallic oxide, in a blast furnace shaft; producing furnace gas containing CO.sub.2, in the blast furnace shaft; discharging the furnace gas from the blast furnace shaft; directing at least a portion of the furnace gas directly or indirectly into a CO.sub.2-converter; and converting the CO.sub.2 contained in the furnace gas into an aerosol consisting of a carrier gas and C-particles in the CO.sub.2-converter in the presence of a stoichiometric surplus of C; directing at least a first portion of the aerosol from the CO.sub.2-converter into the blast furnace shaft; and introducing H.sub.2O into the blast furnace shaft. By virtue of the reaction C+H.sub.2O.fwdarw.CO.sub.2+2H, nascent hydrogen is produced in the blast furnace which causes rapid reduction of the metal ore. The speed of reduction of the metal ore is thus increased, and it is possible to increase either the throughput capacity of the blast furnace or to reduce the size of the blast furnace. An aerosol in the form of a fluid is easily introducible into the blast furnace shaft.

A method for manufacturing direct reduced iron wherein iron ore is reduced in a direct reduction furnace by a reducing gas, the reducing gas exiting the furnace through the top as a top reduction gas. The top reduction gas is captured and at least partly subjected to a CO2 recovery step during which it is divided into two streams, a CO2-rich stream and a CO2-poor stream. The CO2-rich stream is subjected to an alkanol production step to produce an alkanol product.

Described are a method and a system for producing porous iron by means of a direct reduction process. In said method and system, a reducing gas is introduced into a DRI reduction device, and the direct reduction process is carried out therein. Coke oven gas and/or natural gas is/are reformed by adding gas, which contains steam and carbon dioxide and which is top gas from a DRI reduction device, and oxygen in a COG reformer so as to obtain reducing gas.

The present invention provides a novel method for supplying a reducing gas to the shaft part of a blast furnace with which a large amount of reducing gas containing hydrogen at a high concentration can be supplied to a deeper position in the blast furnace (location of the blast furnace closer to the center axis in the radial direction) and with which it is possible to reduce the total generated amount of CO.sub.2 of the CO.sub.2 amount that is reduced by conducting hydrogen smelting in the blast furnace and the CO.sub.2 amount that is generated during production of the reducing gas supplied to the blast furnace. The method for supplying a reducing gas to the shaft part of a blast furnace according to the present invention is characterized by reforming coke oven gas by increasing the temperature thereof to 1200 to 1800? C. in a reactor in which an oxygen-containing gas is supplied to preheated coke oven gas to generate reformed gas in which hydrogen gas is enriched; mixing the reformed gas with CO-containing gas in the reactor so that the hydrogen concentration of the reducing gas is adjusted to 15-35 vol % (wet); and supplying the resultant reducing gas to the shaft part of the blast furnace under a condition of a ratio of a flow rate of reducing gas blown into shaft part/flow rate of reducing gas blown into tuyere >0.42.