Abstract: A system and method of direct reduction of iron (DRI) is disclosed, having a reduction unit configured to reduce iron oxides to metallic iron; a process gas heater coupled to the reduction unit, the process gas heater configured to supply the reduction unit directly with a source of heated reducing gas, where the process gas heater is further configured to receive a synthetic combustion air stream for heating the reducing gas, the synthetic combustion air stream comprising a source of oxygen with essentially no nitrogen. A method of carbon dioxide emission reduction from a direct reduction of iron (DRI) process is also disclosed.

Abstract: A method of direct reduction of iron (DRI) is disclosed, the method comprising generating metallic iron by removing oxygen from iron ore using a reducing gaseous mixture with excess carbon monoxide that produces an excess CO2 by-product is provided. CO2 by-product is optionally sequestered. A system for carrying out the method is also disclosed.

Abstract: 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.

Abstract: 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.

Abstract: A method for producing high carbon content metallic iron using coke oven gas, including: dividing a top gas stream from a direct reduction shaft furnace into a first top gas stream and a second top gas stream; mixing the first top gas stream with a coke oven gas stream from a coke oven gas source and processing at least a portion of a resulting combined coke oven gas stream in a carbon dioxide separation unit to form a synthesis gas-rich gas stream and a carbon-dioxide rich gas stream; delivering the synthesis gas-rich gas stream to the direct reduction shaft furnace as bustle gas; using the carbon-dioxide rich gas stream as fuel gas in one or more heating units; and delivering the second top gas stream to the direct reduction shaft furnace as bustle gas.

Abstract: The present invention provides a method for reducing iron oxide to metallic iron using coke oven gas, including: dividing coke oven gas from a coke oven gas source into a plurality of coke oven gas streams; providing a first coke oven gas stream to a hydrogen enrichment unit to form a hydrogen-rich product stream that is delivered to a reduction shaft furnace as part of a reducing gas stream; and providing a tail gas stream from the hydrogen enrichment unit to a reforming reactor to form a reformed gas stream that is delivered to a reduction shaft furnace as part of the reducing gas stream. Optionally, a spent top gas stream from the reduction shaft furnace is cleansed of CO2 and recycled back to the reducing gas stream.

Abstract: Systems and methods for removal of gas phase contaminants may utilize catalytic oxidation. For example, a method may include passing a gas that includes a gas phase contaminant through a catalytic membrane reactor at a temperature of about 150° C. to about 300° C., wherein the catalytic membrane reactor includes a bundle of tubular inorganic membranes, wherein each of the tubular inorganic membranes comprise a macroporous tubular substrate with an oxidative catalyst and a microporous layer disposed on a bore side of the macroporous tubular substrate, and wherein at least about 50% of the gas flows through the tubular inorganic membranes in a Knudsen flow regime; and oxidizing at least some of the gas phase contaminant with the oxidative catalyst layer, thereby reducing a concentration of the gas phase contaminant in the gas.

Abstract: 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.

Abstract: 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 to increase the carbon content of resulting direct reduced iron. 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, at least in part, from a carbon monoxide recovery unit that forms the carbon monoxide-rich gas stream and an effluent gas stream.

Abstract: A method for producing high carbon content metallic iron using coke oven gas, including: dividing a top gas stream from a direct reduction shaft furnace into a first top gas stream and a second top gas stream; mixing the first top gas stream with a coke oven gas stream from a coke oven gas source and processing at least a portion of a resulting combined coke oven gas stream in a carbon dioxide separation unit to form a synthesis gas-rich gas stream and a carbon-dioxide rich gas stream; delivering the synthesis gas-rich gas stream to the direct reduction shaft furnace as bustle gas; using the carbon-dioxide rich gas stream as fuel gas in one or more heating units; and delivering the second top gas stream to the direct reduction shaft furnace as bustle gas.

Abstract: The present invention provides a method for reducing iron oxide to metallic iron using coke oven gas, including: dividing coke oven gas from a coke oven gas source into a plurality of coke oven gas streams; providing a first coke oven gas stream to a hydrogen enrichment unit to form a hydrogen-rich product stream that is delivered to a reduction shaft furnace as part of a reducing gas stream; and providing a tail gas stream from the hydrogen enrichment unit to a reforming reactor to form a reformed gas stream that is delivered to a reduction shaft furnace as part of the reducing gas stream. Optionally, a spent top gas stream from the reduction shaft furnace is cleansed of CO2 and recycled back to the reducing gas stream.