A direct reduction method and system including an electric heater system adapted to heat a reduction gas and a shaft furnace adapted to receive and utilize the heated reduction gas and one or more of a carbonaceous gas and/or material to produce the direct reduced iron containing carbon, including: providing the reduction gas to an electric heating elements of the electric heater system to heat the reduction gas; stopping the providing the reduction gas; and providing a hydrogen gas or a hydrogen gas with added steam to remove carbon deposition from the electric heating elements of the electric heater system while continuing to heat the reduction gas such that the direct reduced iron production including carbon is not interrupted.
A direct reduction method and system including an electric heater system adapted to heat a reduction gas and a shaft furnace adapted to receive and utilize the heated reduction gas and one or more of a carbonaceous gas and/or material to produce the direct reduced iron containing carbon, including: providing the reduction gas to an electric heating elements of the electric heater system to heat the reduction gas; stopping the providing the reduction gas; and providing a hydrogen gas or a hydrogen gas with added steam to remove carbon deposition from the electric heating elements of the electric heater system while continuing to heat the reduction gas such that the direct reduced iron production including carbon is not interrupted.
A method and system for producing a direct reduced iron product, including: generating hot direct reduced iron in a shaft furnace; receiving the hot direct reduced iron in a feed-leg downstream of the shaft furnace; and adding carbon to the hot direct reduced iron in the feed-leg downstream of the shaft furnace to form the direct reduced iron product. The process may further include receiving and briquetting the hot direct reduced iron with the carbon added to form the direct reduced iron product. The process may further include receiving the hot direct reduced iron in an additional (optionally parallel) feed-leg downstream of the shaft furnace and adding other carbon (in a different amount) to the hot direct reduced iron in the additional feed-leg downstream of the shaft furnace to form an additional direct reduced iron product having a different carbon content, using the same stream of hot direct reduced iron.
Direct reduction systems and methods utilize a direct reduction shaft furnace to reduce the iron oxide with a reduction gas received from a reduction/recycle gas loop. An electric gas heating system disposed in the reduction/recycle gas loop heats up the reduction gas with make-up hydrogen and/or natural gas before introducing to the shaft furnace. The gas heating system includes, in sequence, a primary gas heating unit utilizing a direct or indirect heating mechanism to first heat the reduction gas to a temperature below 600°C or above 700°C to avoid carbon deposition in the gas heating system and a secondary gas heating unit utilizing a direct heating mechanism to second heat the reduction gas to the temperature between 900°C and 1100°C.
A method and system for producing synthesis gas for the production of direct reduced iron in a direct reduction shaft furnace, including: preheating cold feed gas in a heater to form hot feed gas; adding preheated external hydrogen gas to the hot feed gas downstream of the heater; feeding the hot feed gas and the preheated external hydrogen added to the hot feed gas to a reformer; and reforming the hot feed gas and the preheated external hydrogen added to the hot feed gas in the reformer to form the synthesis gas. The method and system also include feeding the synthesis gas to a bustle of the direct reduction shaft furnace for the production of the direct reduced iron in the direct reduction shaft furnace. The method may include adding preheated external hydrogen gas to the synthesis gas downstream of the reformer and upstream of the direct reduction shaft furnace.
A method and system for producing a direct reduced iron product, including: generating hot direct reduced iron in a shaft furnace; receiving the hot direct reduced iron in a feed-leg downstream of the shaft furnace; and adding carbon to the hot direct reduced iron in the feed-leg downstream of the shaft furnace to form the direct reduced iron product. The process may further include receiving and briquetting the hot direct reduced iron with the carbon added to form the direct reduced iron product. The process may further include receiving the hot direct reduced iron in an additional (optionally parallel) feed-leg downstream of the shaft furnace and adding other carbon (in a different amount) to the hot direct reduced iron in the additional feed-leg downstream of the shaft furnace to form an additional direct reduced iron product having a different carbon content, using the same stream of hot direct reduced iron.
A method and system for producing synthesis gas for the production of direct reduced iron in a direct reduction shaft furnace, including: preheating cold feed gas in a heater to form hot feed gas; adding preheated external hydrogen gas to the hot feed gas downstream of the heater; feeding the hot feed gas and the preheated external hydrogen added to the hot feed gas to a reformer; and reforming the hot feed gas and the preheated external hydrogen added to the hot feed gas in the reformer to form the synthesis gas. The method and system also include feeding the synthesis gas to a bustle of the direct reduction shaft furnace for the production of the direct reduced iron in the direct reduction shaft furnace. The method may include adding preheated external hydrogen gas to the synthesis gas downstream of the reformer and upstream of the direct reduction shaft furnace.
Direct reduction systems and methods utilize a direct reduction shaft furnace to reduce the iron oxide with a reduction gas received from a reduction/recycle gas loop. An electric gas heating system disposed in the reduction/recycle gas loop heats up the reduction gas with make-up hydrogen and/or natural gas before introducing to the shaft furnace. The gas heating system includes, in sequence, a primary gas heating unit utilizing a direct or indirect heating mechanism to first heat the reduction gas to a temperature below 600° C. or above 700° C. to avoid carbon deposition in the gas heating system and a secondary gas heating unit utilizing a direct heating mechanism to second heat the reduction gas to the temperature between 900° C. and 1100° C.
A method of heating direct reduced iron between a direct reduced iron source and processing equipment for the direct reduced iron, comprises providing a conduit heater assembly between the direct reduced iron source and the processing equipment, wherein the conduit heater assembly receives a flow of the direct reduced iron from the direct reduced iron source and heats the direct reduced iron as the direct reduced iron flows through the conduit heater assembly and to the processing equipment.
A method of heating direct reduced iron between a direct reduced iron source and processing equipment for the direct reduced iron, comprises providing a conduit heater assembly between the direct reduced iron source and the processing equipment, wherein the conduit heater assembly receives a flow of the direct reduced iron from the direct reduced iron source and heats the direct reduced iron as the direct reduced iron flows through the conduit heater assembly and to the processing equipment.
C21B 13/02 - Making spongy iron or liquid steel, by direct processes in shaft furnaces
C21B 13/00 - Making spongy iron or liquid steel, by direct processes
F27D 5/00 - Supports, screens or the like for the charge within the furnace
F27D 11/06 - Induction heating, i.e. in which the material being heated, or its container or elements embodied therein, form the secondary of a transformer
11.
HOT METAL PRODUCTION FROM DRI WITH ELECTRIC ARC HEATING
According to embodiments, disclosed is a method and system to maintain the soft and sparse slag characteristic favorable for an electric arc to efficiently transfer the energy to molten iron with the power input per furnace area higher than 600KW/m2 while keeping FeO amount less than 5% in the slag and carbon amount higher than 2.5% in the product hot metal at a DRI melting furnace.
According to embodiments, disclosed is a method and system to maintain the soft and sparse slag characteristic favorable for an electric arc to efficiently transfer the energy to molten iron with the power input per furnace area higher than 600 KW/m2 while keeping FeO amount less than 5% in the slag and carbon amount higher than 2.5% in the product hot metal at a DRI melting furnace.
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 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.
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.
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.
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.
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.
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.
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.
A briquette cooling conveyor system includes an apron pan conveyor. The apron pan conveyor includes: an apron pan with openings adapted to drain water from the apron pan conveyor, an apron pan upper, carry strand, and an apron pan lower, return strand. The briquette cooling conveyor system further includes a carriage side flushing hopper positioned between the apron pan upper, carry strand and the apron pan lower, return strand, and the carriage side flushing hopper is configured to capture fines and water from the system.
C21B 13/00 - Making spongy iron or liquid steel, by direct processes
B65G 15/08 - Conveyors having endless load-conveying surfaces, i.e. belts and like continuous members, to which tractive effort is transmitted by means other than endless driving elements of similar configuration the load-carrying surface being formed by a concave or tubular belt, e.g. a belt forming a trough
B65G 17/06 - Conveyors having an endless traction element, e.g. a chain, transmitting movement to a continuous or substantially-continuous load-carrying surface or to a series of individual load-carriersEndless-chain conveyors in which the chains form the load-carrying surface having a load-carrying surface formed by a series of interconnected, e.g. longitudinal, links, plates, or platforms
A briquette cooling conveyor system includes an apron pan conveyor. The apron pan conveyor includes: an apron pan with openings adapted to drain water from the apron pan conveyor, an apron pan upper, carry strand, and an apron pan lower, return strand. The briquette cooling conveyor system further includes a carriage side flushing hopper positioned between the apron pan upper, carry strand and the apron pan lower, return strand, and the carriage side flushing hopper is configured to capture fines and water from the system.
B65G 17/00 - Conveyors having an endless traction element, e.g. a chain, transmitting movement to a continuous or substantially-continuous load-carrying surface or to a series of individual load-carriersEndless-chain conveyors in which the chains form the load-carrying surface
B65G 47/44 - Arrangements or applications of hoppers or chutes
F26B 11/04 - Machines or apparatus for drying solid materials or objects with movement which is non-progressive in moving drums or other mainly-closed receptacles rotating about a horizontal or slightly-inclined axis
F26B 13/10 - Arrangements for feeding, heating or supporting materialsControlling movement, tension or position of materials
A briquette cooling conveyor system includes an apron pan conveyor. The apron pan conveyor includes: an apron pan with openings adapted to drain water from the apron pan conveyor, an apron pan upper, carry strand, and an apron pan lower, return strand. The briquette cooling conveyor system further includes a carriage side flushing hopper positioned between the apron pan upper, carry strand and the apron pan lower, return strand, and the carriage side flushing hopper is configured to capture fines and water from the system.
F26B 11/04 - Machines or apparatus for drying solid materials or objects with movement which is non-progressive in moving drums or other mainly-closed receptacles rotating about a horizontal or slightly-inclined axis
24.
OXYGEN INJECTION FOR REFORMER FEED GAS FOR DIRECT REDUCTION PROCESS
A direct reduction plant is disclosed. The direct reduction plant includes an oxygen injection system, a reformer, and a shaft furnace. The oxygen injection system includes an oxygen injection reactor and a main oxygen burner. The oxygen injection reactor is adapted to receive a gas mixture. The main oxygen burner is adapted to increase a temperature of the gas mixture by burning a mixture of fuel and oxygen fed to the main oxygen burner. The reformer is adapted to reform the gas mixture with the increased temperature. The shaft furnace is adapted to reduce iron ore using the reformed gas mixture.
A direct reduction plant is disclosed. The direct reduction plant includes an oxygen injection system, a reformer, and a shaft furnace. The oxygen injection system includes an oxygen injection reactor and a main oxygen burner. The oxygen injection reactor is adapted to receive a gas mixture. The main oxygen burner is adapted to increase a temperature of the gas mixture by burning a mixture of fuel and oxygen fed to the main oxygen burner. The reformer is adapted to reform the gas mixture with the increased temperature. The shaft furnace is adapted to reduce iron ore using the reformed gas mixture.
A direct reduction plant is disclosed. The direct reduction plant includes an oxygen injection system, a reformer, and a shaft furnace. The oxygen injection system includes an oxygen injection reactor and a main oxygen burner. The oxygen injection reactor is adapted to receive a gas mixture. The main oxygen burner is adapted to increase a temperature of the gas mixture by burning a mixture of fuel and oxygen fed to the main oxygen burner. The reformer is adapted to reform the gas mixture with the increased temperature. The shaft furnace is adapted to reduce iron ore using the reformed gas mixture.
A process cooling water (PCW) system and method for an iron or steelmaking application, the PCW system and method including: sampling a plurality of characteristics of PCW using a plurality of sensors; calculating one or more of Langelier Saturation Index (LSI) and Ryznar Stability Index (RSI) based on the plurality of characteristics using a LSI/RSI measurement unit coupled to the plurality of sensors; and injecting one or more anti-sealant chemicals into the PCW responsive to the calculated one or more of the LSI and the RSI in real time using an anti-sealant injection system to thereby control scale formation in the PCW.
C02F 5/10 - Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents using organic substances
C02F 5/12 - Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents using organic substances containing nitrogen
C02F 5/14 - Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents using organic substances containing phosphorus
28.
SEAL GAS OPTIMIZATION SYSTEMS AND METHODS FOR A DIRECT REDUCTION PROCESS
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 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.
A62D 3/36 - Detoxification by using acid or alkaline reagents
B01J 10/00 - Chemical processes in general for reacting liquid with gaseous media other than in the presence of solid particlesApparatus specially adapted therefor
C02F 1/66 - Treatment of water, waste water, or sewage by neutralisationTreatment of water, waste water, or sewage pH adjustment
C21B 13/00 - Making spongy iron or liquid steel, by direct processes
30.
Seal gas optimization systems and methods for a direct reduction process
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 direct reduction process comprises providing a shaft furnace of a direct reduction plant to reduce iron oxide with reducing gas; providing a direct reduced iron melting furnace; and coupling a discharge chute between a discharge exit of the direct reduced shaft furnace and an inlet of the direct reduced iron melting furnace; wherein direct reduced iron and the reducing gas from the shaft furnace flow through the discharge chute and the reducing gas controls the melting furnace atmosphere to reducing environment.
A method for producing direct reduced iron having increased carbon content, comprises delivering each of the herein-described mixed carburizing gas streams, which are of different composition, to a transition zone of a direct reduction furnace, and exposing partially or completely reduced iron oxide to the mixed carburizing gas streams to increase the carbon content of resulting direct reduced iron to greater than 4.5 wt. %.
A method of heating direct reduced iron between a direct reduced iron source and processing equipment for the direct reduced iron, comprises providing a conduit heater assembly between the direct reduced iron source and the processing equipment, wherein the conduit heater assembly receives a flow of the direct reduced iron from the direct reduced iron source and heats the direct reduced iron as the direct reduced iron flows through the conduit heater assembly and to the processing equipment.
C21B 13/02 - Making spongy iron or liquid steel, by direct processes in shaft furnaces
C21B 13/00 - Making spongy iron or liquid steel, by direct processes
F27B 1/21 - Arrangement of devices for discharging
F27D 5/00 - Supports, screens or the like for the charge within the furnace
F27D 11/06 - Induction heating, i.e. in which the material being heated, or its container or elements embodied therein, form the secondary of a transformer
F27D 99/00 - Subject matter not provided for in other groups of this subclass
34.
Integration of DR plant and electric DRI melting furnace for producing high performance iron
A direct reduction process comprises providing a shaft furnace of a direct reduction plant to reduce iron oxide with reducing gas; providing a direct reduced iron melting furnace; and coupling a discharge chute between a discharge exit of the direct reduced shaft furnace and an inlet of the direct reduced iron melting furnace; wherein direct reduced iron and the reducing gas from the shaft furnace flow through the discharge chute and the reducing gas controls the melting furnace atmosphere to reducing environment.
A method for producing direct reduced iron having increased carbon content, comprises: providing a carbon monoxide-rich gas stream, and separating the carbon monoxide-rich gas stream into at least two separate carbon monoxide-rich gas streams; providing a hydrocarbon- rich gas stream and separating the hydrocarbon-rich gas stream into at least two separate hydrocarbon-rich gas streams; blending one of the carbon monoxide-rich gas streams with one of the hydrocarbon-rich gas streams to form a mixed carburizing gas stream; blending another carbon monoxide-rich gas stream of the at least two separate carbon monoxide-rich gas streams with another hydrocarbon-rich gas stream of the at least two separate hydrocarbon-rich gas streams to form a distinct mixed carburizing gas stream; delivering each of the mixed carburizing gas streams, which are of different composition, to a transition zone of a direct reduction furnace, and exposing partially or completely reduced iron oxide to the mixed carburizing gas streams to increase the carbon content of resulting direct reduced iron to greater than 4.5 wt.%.
A direct reduction process comprises providing a shaft furnace of a direct reduction plant to reduce iron oxide with reducing gas; providing a direct reduced iron melting furnace; and coupling a discharge chute between a discharge exit of the direct reduced shaft furnace and an inlet of the direct reduced iron melting furnace; wherein direct reduced iron and the reducing gas from the shaft furnace flow through the discharge chute and the reducing gas controls the melting furnace atmosphere to reducing environment.
A method of heating direct reduced iron between a direct reduced iron source and processing equipment for the direct reduced iron, comprises providing a conduit heater assembly between the direct reduced iron source and the processing equipment, wherein the conduit heater assembly receives a flow of the direct reduced iron from the direct reduced iron source and heats the direct reduced iron as the direct reduced iron flows through the conduit heater assembly and to the processing equipment.
F24H 3/04 - Air heaters with forced circulation the air being in direct contact with the heating medium, e.g. electric heating element
F24H 9/20 - Arrangement or mounting of control or safety devices
H05B 3/16 - Heating elements characterised by the composition or nature of the materials or by the arrangement of the conductor the conductor being mounted on an insulating base
38.
METHODS AND SYSTEMS FOR INCREASING THE CARBON CONTENT OF DIRECT REDUCED IRON IN A REDUCTION FURNACE
A method for producing direct reduced iron having increased carbon content, comprises: providing a carbon monoxide-rich gas stream, and separating the carbon monoxide-rich gas stream into at least two separate carbon monoxide-rich gas streams; providing a hydrocarbon- rich gas stream and separating the hydrocarbon-rich gas stream into at least two separate hydrocarbon-rich gas streams; blending one of the carbon monoxide-rich gas streams with one of the hydrocarbon-rich gas streams to form a mixed carburizing gas stream; blending another carbon monoxide-rich gas stream of the at least two separate carbon monoxide-rich gas streams with another hydrocarbon-rich gas stream of the at least two separate hydrocarbon-rich gas streams to form a distinct mixed carburizing gas stream; delivering each of the mixed carburizing gas streams, which are of different composition, to a transition zone of a direct reduction furnace, and exposing partially or completely reduced iron oxide to the mixed carburizing gas streams to increase the carbon content of resulting direct reduced iron to greater than 4.5 wt.%.
A method of heating direct reduced iron between a direct reduced iron source and processing equipment for the direct reduced iron, comprises providing a conduit heater assembly between the direct reduced iron source and the processing equipment, wherein the conduit heater assembly receives a flow of the direct reduced iron from the direct reduced iron source and heats the direct reduced iron as the direct reduced iron flows through the conduit heater assembly and to the processing equipment.
F24H 3/04 - Air heaters with forced circulation the air being in direct contact with the heating medium, e.g. electric heating element
F24H 9/20 - Arrangement or mounting of control or safety devices
H05B 3/16 - Heating elements characterised by the composition or nature of the materials or by the arrangement of the conductor the conductor being mounted on an insulating base
42 - Scientific, technological and industrial services, research and design
Goods & Services
Remote electronic monitoring services of iron and steelmaking plants by computerized means comprised of computers and sensors for use in electronic data collection to increase the operational efficiency of iron and steelmaking plants
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 forrn a reforrned 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 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 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 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.
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.
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.
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 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 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.
An oxygen injection system for a direct reduction process, including: a common circumferential gas injection header adapted to be coupled to an oxygen source and an enrichment natural gas source and adapted to deliver oxygen from the oxygen source and enrichment natural gas from the enrichment natural gas source to a reducing gas stream flowing through a conduit axially disposed within the common circumferential gas injection header through a plurality of circumferentially disposed ports to form a bustle gas stream; wherein the common circumferential gas injection header includes a circumferential oxygen injection header adapted to deliver the oxygen from the oxygen source to the reducing gas stream through the plurality of circumferentially disposed ports and a circumferential enrichment natural gas injection header adapted to deliver the enrichment natural gas from the enrichment natural gas source to the reducing gas stream through the plurality of circumferentially disposed ports.
C01B 3/36 - Production of hydrogen or of gaseous mixtures containing hydrogen by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide, air by reaction of hydrocarbons with gasifying agents using oxygen or mixtures containing oxygen as gasifying agents
C21B 13/00 - Making spongy iron or liquid steel, by direct processes
51.
OXYGEN INJECTION SYSTEM FOR A DIRECT REDUCTION PROCESS
An oxygen injection system for a direct reduction process, including: a common circumferential gas injection header adapted to be coupled to an oxygen source and an enrichment natural gas source and adapted to deliver oxygen from the oxygen source and enrichment natural gas from the enrichment natural gas source to a reducing gas stream flowing through a conduit axially disposed within the common circumferential gas injection header through a plurality of circumferentially disposed ports to form a bustle gas stream; wherein the common circumferential gas injection header includes a circumferential oxygen injection header adapted to deliver the oxygen from the oxygen source to the reducing gas stream through the plurality of circumferentially disposed ports and a circumferential enrichment natural gas injection header adapted to deliver the enrichment natural gas from the enrichment natural gas source to the reducing gas stream through the plurality of circumferentially disposed ports.
C01B 3/36 - Production of hydrogen or of gaseous mixtures containing hydrogen by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide, air by reaction of hydrocarbons with gasifying agents using oxygen or mixtures containing oxygen as gasifying agents
C21B 13/00 - Making spongy iron or liquid steel, by direct processes
52.
Oxygen injection system for a direct reduction process
An oxygen injection system for a direct reduction process, including: a common circumferential gas injection header adapted to be coupled to an oxygen source and an enrichment natural gas source and adapted to deliver oxygen from the oxygen source and enrichment natural gas from the enrichment natural gas source to a reducing gas stream flowing through a conduit axially disposed within the common circumferential gas injection header through a plurality of circumferentially disposed ports to form a bustle gas stream; wherein the common circumferential gas injection header includes a circumferential oxygen injection header adapted to deliver the oxygen from the oxygen source to the reducing gas stream through the plurality of circumferentially disposed ports and a circumferential enrichment natural gas injection header adapted to deliver the enrichment natural gas from the enrichment natural gas source to the reducing gas stream through the plurality of circumferentially disposed ports.
A method and apparatus for producing direct reduced iron (DRI), including: generating a reducing gas in a coal gasifier using coal, oxygen, steam, and a first coke oven gas (COG) stream as inputs to the coal gasifier; and delivering the reducing gas to a shaft furnace and exposing iron ore agglomerates to the reducing gas to form metallic iron agglomerates. The method further includes delivering a second COG stream directly to the shaft furnace.
A shaft furnace for producing metallic direct reduced iron (DRI) from iron-containing pellets or lumps and reducing gas disposed therein, including: a circumferential outer wall defining a top interior reducing zone, a middle interior transition zone, and a bottom interior cooling zone, wherein the iron-containing pellets or lumps travel downwards through the top interior reducing zone, the middle interior transition zone, and the bottom interior cooling zone as the iron-containing pellets or lumps encounter the upward-flowing reducing gas and one or more other gases; and a flow diverter disposed along a centerline of the circumferential outer wall including a convex-upwards upper tapering section disposed in the middle transition zone defined by the circumferential outer wall coupled to a convex-downwards lower tapering section disposed in the bottom cooling zone defined by the circumferential outer wall.
A shaft furnace for producing metallic direct reduced iron (DRI) from iron-containing pellets or lumps and reducing gas disposed therein, including: a circumferential outer wall defining a top interior reducing zone, a middle interior transition zone, and a bottom interior cooling zone, wherein the iron-containing pellets or lumps travel downwards through the top interior reducing zone, the middle interior transition zone, and the bottom interior cooling zone as the iron-containing pellets or lumps encounter the upward-flowing reducing gas and one or more other gases; and a flow diverter disposed along a centerline of the circumferential outer wall including a convex-upwards upper tapering section disposed in the middle transition zone defined by the circumferential outer wall coupled to a convex-downwards lower tapering section disposed in the bottom cooling zone defined by the circumferential outer wall.
A shaft furnace for producing metallic direct reduced iron (DRI) from iron-containing pellets or lumps and reducing gas disposed therein, including: a circumferential outer wall defining a top interior reducing zone, a middle interior transition zone, and a bottom interior cooling zone, wherein the iron-containing pellets or lumps travel downwards through the top interior reducing zone, the middle interior transition zone, and the bottom interior cooling zone as the iron-containing pellets or lumps encounter the upward-flowing reducing gas and one or more other gases; and a flow diverter disposed along a centerline of the circumferential outer wall including a convex-upwards upper tapering section disposed in the middle transition zone defined by the circumferential outer wall coupled to a convex-downwards lower tapering section disposed in the bottom cooling zone defined by the circumferential outer wall.
A method and apparatus for producing direct reduced iron (DRI), including: generating a reducing gas in a coal gasifier using coal, oxygen, steam, and a first coke oven gas (COG) stream as inputs to the coal gasifier; and delivering the reducing gas to a shaft furnace and exposing iron ore agglomerates to the reducing gas to form metallic iron agglomerates. The method further includes delivering a second COG stream directly to the shaft furnace.
A method for producing direct reduced iron having increased carbon content, comprising: providing a carbon monoxide-rich gas stream; and delivering the carbonmonoxide-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.
A method for mitigating the buildup of direct reduced iron (DRI) clusters on the walls of a direct reduction (DR) furnace, including: injecting one or more of lime, dolomite, and another anti-sticking agent into a charge disposed within a reduction zone of the DR furnace by: (1) injecting the one or more of lime, dolomite, and another anti-sticking agent into a bustle gas stream upstream of or in a bustle of the DR furnace; (2) injecting the one or more of lime, dolomite, and another anti-sticking agent into the bustle gas stream through a pipe collocated with a bustle gas port through which the bustle gas stream is introduced into the DR furnace; and (3) injecting the one or more of lime, dolomite, and another anti-sticking agent directly into the reduction zone of the DR furnace separate from the bustle gas stream.
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 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.
F25J 3/02 - Processes or apparatus for separating the constituents of gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
62.
METHODS AND SYSTEMS FOR INCREASING THE CARBON CONTENT OF SPONGE IRON IN A REDUCTION FURNACE
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 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.
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.
Methods and systems for producing direct reduced iron (DRI), comprising: generating a syngas stream in a carbon dioxide (C02) and steam reformer; and providing the syngas stream to a direct reduction (DR) shaft furnace as a reducing gas stream. The methods and systems also comprise combining the syngas stream with a recycled off-gas stream from the DR shaft furnace to form the reducing gas stream. The methods and systems further comprise removing carbon dioxide (C02) from the recycled off-gas stream from the DR shaft furnace prior to combining it with the syngas stream to form the reducing gas stream. The methods and systems still further comprise feeding C02 removed from the recycled off-gas stream from the DR shaft furnace to the C02 and steam reformer. The methods and systems still further comprise feeding recycled off-gas from the recycled off-gas stream from the DR shaft furnace to the C02 and steam reformer.
Methods and systems for producing direct reduced iron (DRI), comprising: generating a syngas stream in a carbon dioxide (CO2) and steam reformer; and providing the syngas stream to a direct reduction (DR) shaft furnace as a reducing gas stream. The methods and systems also comprise combining the syngas stream with a recycled off-gas stream from the DR shaft furnace to form the reducing gas stream. The methods and systems further comprise removing carbon dioxide (CO2) from the recycled off-gas stream from the DR shaft furnace prior to combining it with the syngas stream to form the reducing gas stream. The methods and systems still further comprise feeding CO2 removed from the recycled off-gas stream from the DR shaft furnace to the CO2 and steam reformer. The methods and systems still further comprise feeding recycled off-gas from the recycled off-gas stream from the DR shaft furnace to the CO2 and steam reformer.
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.
A process for producing reducing gas for use in the production of direct reduced iron (DRI) and fuel gas for use in a steel mill, including: compressing a coke oven gas (COG) stream in a compressor; passing the compressed coke oven gas stream through an activated charcoal bed to remove tars from the compressed coke oven gas stream; separating a hydrogen-rich gas stream from the compressed cleaned coke oven gas stream using a pressure swing absorption unit; providing the hydrogen-rich gas stream to a direct reduction shaft furnace as reducing gas; and providing a remaining gas stream from the pressure swing absorption unit to a steel mill as fuel gas. Both once-through and recycle options are presented. Optionally, basic oxygen furnace gas (BOFG) is added to the reducing gas.
C21B 13/00 - Making spongy iron or liquid steel, by direct processes
C21B 13/02 - Making spongy iron or liquid steel, by direct processes in shaft furnaces
C01B 3/02 - Production of hydrogen or of gaseous mixtures containing hydrogen
C01B 3/50 - Separation of hydrogen or hydrogen containing gases from gaseous mixtures, e.g. purification
C01B 3/56 - Separation of hydrogen or hydrogen containing gases from gaseous mixtures, e.g. purification by contacting with solidsRegeneration of used solids
70.
METHODS AND SYSTEMS FOR PRODUCING DIRECT REDUCED IRON AND STEEL MILL FUEL GAS
A process for producing reducing gas for use in the production of direct reduced iron (DRI) and fuel gas for use in a steel mill, comprising: compressing a coke oven gas (COG) stream in a compressor; passing the compressed coke oven gas stream through an activated charcoal bed to remove tars from the compressed coke oven gas stream; separating a hydrogen-rich gas stream from the · compressed cleaned coke oven gas stream using a pressure swing absorption unit; providing the hydrogen-rich gas stream to a direct reduction shaft furnace as reducing gas; and providing a remaining gas stream from the pressure swing absorption unit to a steel mill as fuel gas. Both once through and recycle options are presented. Optionally, basic oxygen fumace gas (BOFG) is added to the reducing gas.
C10K 1/32 - Purifying combustible gases containing carbon monoxide with selectively absorptive solids, e.g. active carbon
C10K 3/00 - Modifying the chemical composition of combustible gases containing carbon monoxide to produce an improved fuel, e.g. one of different calorific value, which may be free from carbon monoxide
C21B 13/02 - Making spongy iron or liquid steel, by direct processes in shaft furnaces
71.
Methods and systems for producing direct reduced iron utilizing a petroleum refinery bottoms or petroleum coke gasifier and a hot gas cleaner
Methods and systems for producing DRI utilizing a petroleum refinery bottoms (i.e. heavy fuel oil, vacuum residue, visbreaker tar, asphalt, etc.) or petroleum coke gasifier and a hot gas cleaner. Cooling of the hot synthesis gas generated by the petroleum refinery bottoms or petroleum coke gasifier to <200 C is not necessary. Rather, the synthesis gas from the petroleum refinery bottoms or petroleum coke gasifier is desulfurized and dedusted at high temperature (>350 C) using a hot gas cleaner, well known to those of ordinary skill in the art, although not in such an application. This hot gas cleaner may be high pressure or low pressure.
Methods and systems for producing DRI utilizing a petroleum refinery bottoms (i.e. heavy fuel oil, vacuum residue, visbreaker tar, asphalt, etc.) or petroleum coke gasifier and a hot gas cleaner. Cooling of the hot synthesis gas generated by the petroleum refinery bottoms or petroleum coke gasifier to < 200 C is not necessary. Rather, the synthesis gas from the petroleum refinery bottoms or petroleum coke gasifier is desulfurized and dedusted at high temperature (> 350 C) using a hot gas cleaner, well known to those of ordinary skill in the art, although not in such an application. This hot gas cleaner may be high pressure or low pressure.
C21B 15/00 - Other processes for the manufacture of iron from iron compounds
C10J 3/00 - Production of gases containing carbon monoxide and hydrogen, e.g. synthesis gas or town gas, from solid carbonaceous materials by partial oxidation processes involving oxygen or steam
F02C 3/28 - Gas-turbine plants characterised by the use of combustion products as the working fluid using a special fuel, oxidant, or dilution fluid to generate the combustion products the fuel or oxidant being solid or pulverulent, e.g. in slurry or suspension using a separate gas producer for gasifying the fuel before combustion
C21B 13/06 - Making spongy iron or liquid steel, by direct processes in multi-storied furnaces
C01B 3/36 - Production of hydrogen or of gaseous mixtures containing hydrogen by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide, air by reaction of hydrocarbons with gasifying agents using oxygen or mixtures containing oxygen as gasifying agents
In various exemplary embodiments, the present invention provides systems and methods that can convert clean or raw natural gas, clean or dirty coke oven gas, or the like to reducing gas/syngas suitable for direct reduction with minimal processing or cleaning. Hydrocarbons and the like are converted to H2 and CO. S does not affect the conversion to reducing gas/syngas, but is removed or otherwise cleaned up by the iron bed in the direct reduction shaft furnace. Top gas may be continuously recycled or a once-through approach may be employed.
C01B 3/02 - Production of hydrogen or of gaseous mixtures containing hydrogen
C01B 3/34 - Production of hydrogen or of gaseous mixtures containing hydrogen by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide, air by reaction of hydrocarbons with gasifying agents
C21B 13/02 - Making spongy iron or liquid steel, by direct processes in shaft furnaces
74.
REDUCING IRON OXIDE TO METALLIC IRON USING NATURAL GAS
In various exemplary embodiments, the present invention provides systems and methods that can convert clean or raw natural gas, clean or dirty coke oven gas, or the like to reducing gas/syngas suitable for direct reduction with minimal processing or cleaning. Hydrocarbons and the like are converted to H2 and CO. S does not affect the conversion to reducing gas/syngas, but is removed or otherwise cleaned up by the iron bed in the direct reduction shaft furnace. Top gas may be continuously recycled or a once-through approach may be employed.
Novel systems and methods are described for reducing iron oxide to metallic iron in an integrated steel mill or the like that has a coke oven and/or an oxygen steelmaking furnace. More specifically, the present invention relates to novel systems and methods for reducing iron oxide to metallic iron using coke oven gas (COG) or COG and basic oxygen furnace gas (BOFG).
A method for producing a high purity high carbon molten chrome product from chrome and carbon bearing material, said method comprising the steps of: (a) continuously introducing chrome compacts directly into an electric melter; (b) heating and melting the chrome compacts in the electric melter at a temperature of between about 1300° C to about 1700° C to form high carbon molten chrome; (c) preventing oxidation of the high carbon molten chrome via minimization of the ingress of oxygen containing gas in said heating step; (d) carburizing the high carbon molten chrome to form high carbon molten metallized chrome; (e) purifying the high carbon molten metallized chrome by reducing silicon oxides to silicon and desulfurizing the high carbon molten metallized chrome to produce the high purity high carbon molten chrome product; and (f) discharging the high purity high carbon molten chrome product from the electric melter.
A method for producing a high purity high carbon molten chrome product from chrome and carbon bearing material, said method comprising the steps of: (a) continuously introducing chrome compacts directly into an electric melter; (b) heating and melting the chrome compacts in the electric melter at a temperature of between about 1300° C. to about 1700° C. to form high carbon molten chrome; (c) preventing oxidation of the high carbon molten chrome via minimization of the ingress of oxygen containing gas in said heating step; (d) carburizing the high carbon molten chrome to form high carbon molten metallized chrome; (e) purifying the high carbon molten metallized chrome by reducing silicon oxides to silicon and desulfurizing the high carbon molten metallized chrome to produce the high purity high carbon molten chrome product; and (f) discharging the high purity high carbon molten chrome product from the electric melter.
Processes that generate syngas or reformed gas that have the desired H2/CO ratio, such that they can be used directly for producing higher value liquids, such as using a FT GTL process. The systems and methods of the present invention are simpler and more cost effective than conventional systems and methods. The systems and methods of the present invention generate the required C02 in a reforming furnace by combusting natural gas with a mixture of 02 from an external source and C02 that is recirculated from a reforming furnace. A second application of the natural gas combustion with external 02 mixed with recirculated C02 in the reformer burners can be utilized in a DR process. The reformed gas or syngas containing H2 and CO is used to reduce iron oxide to metallic iron in a shaft furnace, for example.
B01D 53/14 - Separation of gases or vapoursRecovering vapours of volatile solvents from gasesChemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases or aerosols by absorption
C07C 27/00 - Processes involving the simultaneous production of more than one class of oxygen-containing compounds
79.
Systems and methods for generating carbon dioxide for use as a reforming oxidant in making syngas or reformed gas
Processes that generate syngas or reformed gas that have the desired H2/CO ratio, such that they can be used directly for producing higher value liquids, such as using a FT GTL process. The systems and methods of the present invention are simpler and more cost effective than conventional systems and methods. The systems and methods of the present invention generate the required CO2 in a reforming furnace by combusting natural gas with a mixture of O2 from an external source and CO2 that is recirculated from a reforming furnace. A second application of the natural gas combustion with external O2 mixed with recirculated CO2 in the reformer burners can be utilized in a DR process. The reformed gas or syngas containing H2 and CO is used to reduce iron oxide to metallic iron in a shaft furnace, for example.
C01B 3/38 - Production of hydrogen or of gaseous mixtures containing hydrogen by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide, air by reaction of hydrocarbons with gasifying agents using catalysts
C21B 13/02 - Making spongy iron or liquid steel, by direct processes in shaft furnaces
80.
METHODS AND SYSTEMS FOR REDUCING CHROMIUM CONTAINING RAW MATERIAL
A method for reducing a chromium containing material, comprising: combining the chromium containing material comprising chromium oxide with a carbonaceous reductant to form a chromium containing mixture; delivering the chromium containing mixture to a moving hearth furnace and reducing the chromium containing mixture to form a reduced chromium containing mixture; delivering the reduced chromium containing mixture to a smelting furnace; and separating the reduced chromium containing mixture into chromium metal and slag. The method also comprises agglomerating the chromium containing mixture in a granulator or the like. The chromium containing mixture has an average particle size of less than about 200 mesh (about 75 μm).
A method and apparatus for sequestering carbon dioxide from a waste gas and reusing it as a recycled gas without emissions concerns, including: given a gas source divided into a process gas and a waste gas: mixing the process gas with a hydrocarbon and feeding a resulting feed gas into a reformer for reforming the feed gas and forming a reducing gas; and feeding at least a portion of the waste gas into a carbon dioxide scrubber for removing at least some carbon dioxide from the waste gas and forming a carbon dioxide lean gas that is mixed with the reducing gas.
C01B 3/24 - Production of hydrogen or of gaseous mixtures containing hydrogen by decomposition of gaseous or liquid organic compounds of hydrocarbons
C01B 3/38 - Production of hydrogen or of gaseous mixtures containing hydrogen by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide, air by reaction of hydrocarbons with gasifying agents using catalysts
82.
DEVICES AND METHODS FOR ENHANCING BURDEN UNIFORMITY IN A COMBINATION REFORMING/REDUCING SHAFT FURNACE
The present invention provides a combination reforming/reducing shaft furnace for the production of direct reduced iron that utilizes one or more burden uniformity enhancers, such as one or more rotating/reciprocating mixing shafts, one or more stationary flow aids, one or more wall structures/variations, one or more agitators, or the like for ensuring that reforming and reducing in the shaft furnace take place evenly across the width of and throughout the depth of the burden in the shaft furnace.
The present invention provides a combination reforming/reducing shaft furnace for the production of direct reduced iron that utilizes one or more burden uniformity enhancers, such as one or more rotating/reciprocating mixing shafts, one or more stationary flow aids, one or more wall structures/variations, one or more agitators, or the like for ensuring that reforming and reducing in the shaft furnace take place evenly across the width of and throughout the depth of the burden in the shaft furnace.
The present invention provides a combination reforming/reducing shaft furnace for the production of direct reduced iron that utilizes one or more burden uniformity enhancers, such as one or more rotating/reciprocating mixing shafts, one or more stationary flow aids, one or more wall structures/variations, one or more agitators, or the like for ensuring that reforming and reducing in the shaft furnace take place evenly across the width of and throughout the depth of the burden in the shaft furnace.
2 and CO. S does not affect the conversion to reducing gas/syngas, but is removed or otherwise cleaned up by the iron bed in the direct reduction shaft furnace. Top gas may be continuously recycled or a once-through approach may be employed.
Novel systems and methods are described for reducing iron oxide to metallic iron in an integrated steel mill or the like that has a coke oven and/or an oxygen steelmaking furnace. More specifically, the present invention relates to novel systems and methods for reducing iron oxide to metallic iron using coke oven gas (COG) or COG and basic oxygen furnace gas (BOFG).
The present invention provides methods and systems for the production of direct reduced iron, including: removing a top gas from a direct reduction furnace; carbon monoxide shifting the top gas using a carbon monoxide shift reactor to form a carbon monoxide shifted top gas having a reduced carbon monoxide content; adding one of a coal gas, a synthesis gas, and an export gas to at least a portion of the carbon monoxide shifted top gas to form a combined gas; removing carbon dioxide from the combined gas using a carbon dioxide removal unit to form a carbon dioxide lean combined gas; and providing the carbon dioxide lean combined gas to the direct reduction furnace as a reducing gas for producing direct reduced iron after heating to reduction temperature.
Methods and systems for the production of direct reduced iron, including: removing a top gas from a direct reduction furnace; carbon monoxide shifting the top gas using a carbon monoxide shift reactor to form a carbon monoxide shifted top gas having a reduced carbon monoxide content; adding one of a coal gas, a synthesis gas, and an export gas to at least a portion of the carbon monoxide shifted top gas to form a combined gas; removing carbon dioxide from the combined gas using a carbon dioxide removal unit to form a carbon dioxide lean combined gas; and providing the carbon dioxide lean combined gas to the direct reduction furnace as a reducing gas for producing direct reduced iron after heating to reduction temperature. Optionally, the method includes removing carbon dioxide from the top gas using a carbon dioxide removal unit prior to carbon monoxide shifting the top gas.
A method and apparatus for sequestering carbon dioxide from a waste gas and reusing it as a recycled gas without emissions concerns, including: given a gas source divided into a process gas and a waste gas: mixing the process gas with a hydrocarbon and feeding a resulting feed gas into a reformer for reforming the feed gas and forming a reducing gas; and feeding at least a portion of the waste gas into a carbon dioxide scrubber for removing at least some carbon dioxide from the waste gas and forming a carbon dioxide lean gas that is mixed with the reducing gas. Optionally, the method also includes feeding at least a portion of the waste gas into the carbon dioxide scrubber for removing at least some carbon dioxide from the waste gas and forming a fuel gas after the addition of a hydrocarbon that is fed into the reformer. Optionally, the gas source and the reducing gas are associated with a direct reduction process for converting iron oxide to metallic iron in a reduction furnace that utilizes the reducing gas, optionally after some modification, and produces the gas source.
The present disclosure provides a Fischer-Tropsch tail gas recycling system, including: a Fischer-Tropsch reactor providing a source of tail gas; a first preheater for preheating the tail gas to between about 200 and 300 degrees C; a hydrogenator for hydrogenating the tail gas; an expansion device for reducing the pressure of the tail gas to between about 2.5 and 5 bar; a second preheater for preheating a feed gas comprising the tail gas and steam to between about 500 and 600 degrees C; and a catalytic reformer for reforming the feed gas in the presence of a catalyst, wherein the catalytic reformer operates at about 2 bar and about 1000 degrees C, for example. Optionally, C02 and/or natural gas are also added to the tail gas and/or steam to form the feed gas.
The present invention relates generally to a smelting operation or the like, by which molten metal is produced from a metal oxide after metal oxide agglomerates are directly reduced and melted with a carbonaceous material in an electric heating and melting furnace. More specifically, the present invention relates to an electric furnace for producing molten metal that has material recycling capability, especially in-process material recycling capability.
F27B 3/08 - Hearth-type furnaces, e.g. of reverberatory typeElectric arc furnaces heated electrically, e.g. electric arc furnaces, with or without any other source of heat
C21B 13/06 - Making spongy iron or liquid steel, by direct processes in multi-storied furnaces
A process for the direct reduction of iron ore when the external source of reductants is one or both of coke oven gas (COG) and basic oxygen furnace gas (BOFG). Carbon dioxide is removed from a mixture of shaft: furnace off gas, obtained from a conventional direct reduction shaft: furnace, and BOFG. This C02 lean gas is mixed with clean COG, humidified, and heated in an indirect heater. Oxygen is injected into the heated reducing gas. This hot reducing gas flows to the direct reduction shaft furnace for use. The spent hot reducing gas exits the direct reduction shaft furnace as shaft furnace off gas, produces steam in a waste heat boiler, cleaned in a cooler scrubber, compressed, and recycled to join fresh BOFG. A portion of the shaft furnace off gas is sent to the heater burners.
A process for reducing iron oxide to metallic iron using coke oven gas (COG), including: a direct reduction shaft furnace for providing off gas; a COG source for injecting COG into a reducing gas stream including at least a portion of the off gas; and the direct reduction shaft furnace reducing iron oxide to metallic iron using the reducing gas stream and injected COG. The COG has a temperature of about 1,200 degrees C or greater upon injection. The COG has a CH4 content of between about 2% and about 13%. Preferably, the COG is reformed COG. Optionally, the COG is fresh hot COG. The COG source includes a partial oxidation system. Optionally, the COG source includes a hot oxygen burner.
The present invention provides a method for producing direct reduced iron and/or hot metal using high-moisture content carbonaceous material, including: agglomerating carbonaceous material from the high-moisture content carbonaceous material with a metal oxide-bearing material to form an agglomerate suitable for use in a direct reduction and/or hot metal producing process. The method also includes distilling the high-moisture content carbonaceous material. The method further includes dry quenching the carbonaceous material obtained from the distilling step. The method still further includes drying the high-moisture content carbonaceous material with energy from a hot off gas from a furnace for producing direct reduced iron and/or hot metal prior to the distilling step.
The present invention provides a method for producing direct reduced iron and/or hot metal using high-moisture content carbonaceous material, including: agglomerating carbonaceous material from the high-moisture content carbonaceous material with a metal oxide-bearing material to form an agglomerate suitable for use in a direct reduction and/or hot metal producing process. The method also includes distilling the high-moisture content carbonaceous material. The method further includes dry quenching the carbonaceous material obtained from the distilling step. The method still further includes drying the high- moisture content carbonaceous material with energy from a hot off gas from a furnace for producing direct reduced iron and/or hot metal prior to the distilling step.
The present invention relates generally to a smelting operation or the like, by which molten metal is produced from a metal oxide after metal oxide agglomerates are directly reduced and melted with a carbonaceous material in an electric heating and melting furnace. More specifically, the present invention relates to an electric furnace for producing molten metal that has material recycling capability, especially in-process material recycling capability.
C22B 9/05 - Refining by treating with gases, e.g. gas flushing
F03B 13/00 - Adaptations of machines or engines for special useCombinations of machines or engines with driving or driven apparatusPower stations or aggregates
97.
System and method for reducing iron oxide to metallic iron using coke oven gas and oxygen steelmaking furnace gas
4 content of between about 2% and about 13%. Preferably, the COG is reformed COG. Optionally, the COG is fresh hot COG. The COG source includes a partial oxidation system. Optionally, the COG source includes a hot oxygen burner.
The present invention provides a reformer tube apparatus, including: an axially aligned tubular structure including a flange section, a top section, a middle section, and a bottom section; wherein the top section of the axially aligned tubular structure includes a first portion having a first wall thickness; wherein the top section of the axially aligned tubular structure includes a second portion having a second wall thickness; and wherein the top section of the axially aligned tubular structure includes a third portion having a transitioning wall thickness that joins the first portion to the second portion. The flange section includes a concentric flange disposed about a top portion thereof. The bottom section of the tubular structure includes a plurality of concentric wedge structures disposed about the interior thereof. The bottom section of the tubular structure also includes a recess disposed about the exterior thereof. The axially aligned tubular structure further includes a secondary flange section coupled to the flange section, wherein the secondary flange section includes a concentric flange disposed about a top portion thereof. Optionally, the reformer tube apparatus is disposed within a reformer used in a direct reduction process.
C01B 3/38 - Production of hydrogen or of gaseous mixtures containing hydrogen by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide, air by reaction of hydrocarbons with gasifying agents using catalysts
B01J 8/06 - Chemical or physical processes in general, conducted in the presence of fluids and solid particlesApparatus for such processes with stationary particles, e.g. in fixed beds in tube reactorsChemical or physical processes in general, conducted in the presence of fluids and solid particlesApparatus for such processes with stationary particles, e.g. in fixed beds the solid particles being arranged in tubes
B01J 19/02 - Apparatus characterised by being constructed of material selected for its chemically-resistant properties
C21B 13/00 - Making spongy iron or liquid steel, by direct processes
C21B 13/02 - Making spongy iron or liquid steel, by direct processes in shaft furnaces
99.
REFORMER TUBE APPARATUS HAVING VARIABLE WALL THICKNESS AND ASSOCIATED METHOD OF MANUFACTURE
A reformer tube apparatus includes an axially aligned tubular structure including a flange section, a top section, a middle section, and a bottom section. The top section of the axially aligned tubular structure includes a first portion having a first wall thickness, a second portion having a second wall thickness, and a third portion having a transitioning wall thickness that joins the first portion to the second portion. The flange section includes a concentric flange disposed about a top portion thereof. The bottom section of the tubular structure includes a plurality of concentric wedge structures disposed about the interior thereof. The bottom section of the tubular structure also includes a recess disposed about the exterior thereof. The axially aligned tubular structure further includes a secondary flange section coupled to the flange section, wherein the secondary flange section includes a concentric flange disposed about a top portion thereof.
A reformer tube apparatus includes an axially aligned tubular structure including a flange section, a top section, a middle section, and a bottom section. The top section of the axially aligned tubular structure includes a first portion having a first wall thickness, a second portion having a second wall thickness, and a third portion having a transitioning wall thickness that joins the first portion to the second portion. The flange section includes a concentric flange disposed about a top portion thereof. The bottom section of the tubular structure includes a plurality of concentric wedge structures disposed about the interior thereof. The bottom section of the tubular structure also includes a recess disposed about the exterior thereof. The axially aligned tubular structure further includes a secondary flange section coupled to the flange section, wherein the secondary flange section includes a concentric flange disposed about a top portion thereof.
