WO2023170622A1 - Système et procédé de préchauffage de matière première dans la production de produits en ferrochrome - Google Patents

Système et procédé de préchauffage de matière première dans la production de produits en ferrochrome Download PDF

Info

Publication number
WO2023170622A1
WO2023170622A1 PCT/IB2023/052249 IB2023052249W WO2023170622A1 WO 2023170622 A1 WO2023170622 A1 WO 2023170622A1 IB 2023052249 W IB2023052249 W IB 2023052249W WO 2023170622 A1 WO2023170622 A1 WO 2023170622A1
Authority
WO
WIPO (PCT)
Prior art keywords
raw material
hot gas
heat exchanger
preheater unit
feeding
Prior art date
Application number
PCT/IB2023/052249
Other languages
English (en)
Inventor
Benjamin Thomas DU PLESSIS
Donald Bruce GRANT
Original Assignee
Samancor Chrome Limited
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Samancor Chrome Limited filed Critical Samancor Chrome Limited
Publication of WO2023170622A1 publication Critical patent/WO2023170622A1/fr

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
    • C21C5/52—Manufacture of steel in electric furnaces
    • C21C5/5229—Manufacture of steel in electric furnaces in a direct current [DC] electric arc furnace
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
    • C21C5/52—Manufacture of steel in electric furnaces
    • C21C5/5264—Manufacture of alloyed steels including ferro-alloys
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
    • C21C5/56—Manufacture of steel by other methods
    • C21C5/562—Manufacture of steel by other methods starting from scrap
    • C21C5/565—Preheating of scrap
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B2100/00—Handling of exhaust gases produced during the manufacture of iron or steel
    • C21B2100/60—Process control or energy utilisation in the manufacture of iron or steel
    • C21B2100/66—Heat exchange
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C2100/00—Exhaust gas
    • C21C2100/04—Recirculation of the exhaust gas

Definitions

  • This invention relates to a system and process for preheating raw material in the production of ferrochrome products.
  • the system and process are used in the production of ferrochrome products using a DC arc furnace.
  • Preheating is a known concept and is used in many mineral and pyro metallurgical processes.
  • Preheating of furnace feed material as a specific processing step is also known.
  • This preheating step generally includes the use of energy from combustible carbon monoxide (CO) present in furnace exhaust gasses to heat the raw material in a shaft kiln located above the furnace.
  • An example of such shaft kiln is produced by Metso Outotec Oyj in which a porous raw material column is preheated before smelting it in a submerged arc furnace.
  • Preheating is also used in solid reduction processes, which generally include partial pre-reduction of pelletised raw materials to a high level of reduction for feeding at high temperatures and smelting in a submerged arc furnace.
  • a significant disadvantage of the known processes is that, in the preheating step, there is direct contact between the raw material and the hot gas used for heating it. Bringing the hot gas in direct contact with fine raw material has the risk that the fine material may be carried over into the gas stream, which then has to be separated and disposed of post preheating with the solids filtered and return to the feed stream.
  • the direct contact between the raw material and the hot gas could also cause segregation of fine and coarse material, with associated poor gas flow and efficiency as a result. There is furthermore a risk of possible combustion (oxidation) of the carbonaceous materials contained in the raw material.
  • a process for preheating raw material in the production of ferrochrome products including: extracting off-gas produced in a DC arc furnace; feeding the extracted off-gas to a hot gas generator; generating hot gas by using the off-gas as a fuel source in the hot gas generator; feeding the hot gas to at least one preheater unit; feeding the raw material to the at least one preheater unit; conveying the raw material and hot gas along discrete paths in the preheater unit such that there is no direct contact between the hot gas and raw material; heating the raw material in the preheater unit by means of conduction using the hot gas; and extracting heated raw material from the preheater unit for use in the DC arc furnace.
  • the step of heating the raw material may include using a counter flow heat exchanger.
  • the process may include using a tube or plate type heat exchanger, preferably a shell and tube heat exchanger, and conveying the raw material in tubes of the heat exchanger while conveying the hot gas in an internal volume defined by a shell of the heat exchanger surrounding the tubes.
  • the process may include securing the tubes in position by using parallel, spaced apart baffles in the internal volume and directing the flow of hot gas in the internal volume within the shell.
  • the process may include conveying the raw material through the heat exchanger under the force of gravity, preferably by arranging the tubes in a substantially vertical orientation.
  • the process may include feeding raw material to a buffer located at the top of the preheater unit and preferably above the heat exchanger.
  • the process may further include extracting heated raw material from a discharge hopper located at the bottom of the preheater unit and preferably below the heat exchanger.
  • the process may include monitoring and controlling the extraction of heated raw material from the preheater unit in response to operational requirements of the DC arc furnace.
  • the process may further include automatically adjusting feeding parameters of the raw material into the preheater unit, preferably the buffer, based on extraction parameters of the heated raw material from the preheater unit.
  • the process may include monitoring and controlling hot gas properties in response to operational requirements of the DC arc furnace. This may include monitoring and controlling the temperature, humidity and chemical composition of the hot gas.
  • the process may include introducing a secondary fuel source and/or secondary air flow into the hot gas generator.
  • the process may further include extracting dust and/or fumes from the preheater unit. This may include extracting dust and/or fumes from a feed hopper used in delivering raw material to the heat exchanger.
  • the process may further include cleaning and discharging the dust and/or fumes extracted from the preheater unit in a cleaning sub-system, such as a separate, freestanding system for cleaning the extracted dust and/or fumes.
  • the process may further include separating the particulates from the extracted stream of dust and/or fumes and feeding the particulates back into the preheater unit as part of the raw material stream.
  • a system for preheating raw material in the production of ferrochrome products including: a hot gas generator for generating hot gas using off-gas produced in a DC arc furnace as a fuel source in the hot gas generator; at least one preheater unit housing a heat exchanger for heating the raw material using the hot gas produced by the hot gas generator; raw material feeding means for feeding raw material into the at least one preheater unit; extraction means for extracting heated raw material from the at least one preheater unit; and heated raw material feeding means for feeding the extracted, heated raw material to the DC arc furnace; wherein the heat exchanger is a counter flow heat exchanger defining discrete flow paths for the raw material and the hot gas respectively through the heat exchanger such that there is no direct contact between the raw material and the hot gas, thereby using conduction as the primary heat transfer mechanism.
  • the heat exchanger may be a tube or plate type heat exchanger, preferably a shell and tube heat exchanger.
  • the heat exchanger may include tubes for conveying the raw material and an internal volume defined by the shell of the heat exchanger surrounding the tubes for conveying the hot gas around the tubes.
  • Parallel, spaced apart baffles may be provided in the internal volume to secure the tubes in position and to direct the flow of hot gas within the internal volume in the shell.
  • the heat exchanger is preferably arranged such that the tubes are in a substantially vertical orientation so that the raw material is conveyed, in use, through the heat exchanger under the force of gravity.
  • the at least one preheater unit may include a buffer in which the raw material is received.
  • the buffer is preferably located at the top of the preheater unit and more preferably above the heat exchanger.
  • the at least one preheater unit may include a collection container, preferably a discharge hopper, in which heated raw material is collected prior to being discharged or extracted from the preheater unit.
  • the discharge hopper may be located at the bottom of the preheater unit and preferably below the heat exchanger such that heated raw material is collected therein under the force of gravity as it exits the heat exchanger.
  • the hot gas generator may include a primary fuel source inlet through which the off-gas is fed into the hot gas generator, a secondary fuel source inlet through which a secondary fuel source is fed into the hot gas generator, a primary air inlet through which a primary air flow stream enters the hot gas generator and a secondary air inlet through which a secondary air flow stream enters the hot gas generator.
  • the system may include a control system for monitoring and controlling the operations of the system.
  • the control system may include monitoring, measuring and/or control devices for monitoring, measuring and/or controlling the extraction of heated raw material from the preheater unit in response to operational requirements of the DC arc furnace, and/or the hot gas properties in ducting used to convey the hot gas from the hot gas generator to the preheater unit, the buffer and/or the discharge hopper.
  • the system may include adjusting means for automatically adjusting feed parameters of the raw material into the preheater unit in response to extraction parameters of the heated raw material from the preheater unit.
  • the adjusting means for automatically adjusting the feed and/or extraction parameters is preferably controlled by and/or form part of the control system.
  • the system may further include adjusting means for automatically adjusting operational parameters of the hot gas generator to control the temperature, humidity and chemical composition of the hot gas.
  • the adjusting means for automatically adjusting the hot gas operational parameters is preferably controlled by and/or form part of the control system.
  • the system may further include a dust and/or fumes extraction system for extracting dust and/or fumes from the preheater unit.
  • the dust and/or fumes extraction system may be in fluid communication with a feed hopper of the preheater unit to extract dust and/or fumes from the feed hopper.
  • the system may further include a metering system for controlling the extraction of raw material from the at last one preheater unit.
  • the metering system is preferably located below the at least one preheater unit and includes weighing means for weighing the raw material during extraction and feeding means for feeding the extracted raw material to the DC arc furnace.
  • the metering system is preferably enclosed, airtight and insulated to counter heat losses and the ingress of air so as to mitigate the risk of combustion of the raw material.
  • the system may include a cleaning subsystem for cleaning and discharging the dust and/or fumes extracted from the preheater unit and a return line for feeding particulates separated from the extracted stream of dust and/or fumes back into the preheater unit as part of the raw material stream.
  • Figure 1 shows a schematic diagram of a system and process for preheating raw materials in the production of ferrochrome products in accordance with the invention
  • Figure 2 shows an enlarged detail view of one preheater unit of the system of Figure 1. DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS
  • the terms “mounted”, “connected”, “engaged” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings and are thus intended to include direct connections between two members without any other members interposed therebetween and indirect connections between members in which one or more other members are interposed therebetween. Further, “connected” and “engaged” are not restricted to physical or mechanical connections or couplings. Additionally, the words “lower”, “upper”, “upward”, “down” and “downward” designate directions in the drawings to which reference is made. The terminology includes the words specifically mentioned above, derivatives thereof, and words or similar import.
  • the system 10 includes a direct current (DC) arc furnace in which raw material is melted using electrical energy.
  • the furnace 12 is fed with a direct current electrical supply via an electrode column 14 forming part of an electrical circuit 16.
  • the electrical circuit 16 is completed by an anode 18 located at the bottom of the furnace 12 ( Figure 1 ) or as a separate anode device placed under or over the molten bath of the DC Arc furnace (not shown).
  • the electrical circuit 16 includes a DC rectifier 20 supplied by a transformer 22 and an alternating current (AC) supply 24.
  • the raw material is melted by an open DC arc between an end of the electrode 14 and the anode 18, and liquid alloy and slag are drawn off through custom tapping apertures or outlets 26 and 28 respectively. Alloy ingots 30 are typically cast from the liquid alloy drawn off through the outlet 26.
  • the off-gas produced in the smelting process is continuously extracted from the furnace 12 through a chute or duct 32.
  • the off has is conveyed to a gas scrubbing plant 34 where it is cleaned for downstream use.
  • the off-gas may be stored for later use.
  • the off-gas is at an elevated temperature and contains chemical energy in the form of, among other, carbon monoxide (CO) and hydrogen (H 2 ).
  • the off-gas is generally a mixture of CO, H 2 , nitrogen (N), water vapour and other minor gasses as they occur in the furnace waste gas from time to time.
  • From the scrubbing plant 34 the cleaned off-gas runs through a compressor 36 or suitable fan, which is used to get the off-gas to a desired pressure.
  • the off-gas passes through a gas dryer 38 prior to being supplied to a hot gas generator 40.
  • the hot has generator 40 is typically a combustion furnace or chamber. Although only one combustion chamber 40 is shown in Figure 1 , it is envisaged that multiple units or chambers could be used in alternative embodiments.
  • the configuration and number of combustion chambers 40 will generally depend on the operational requirements of the system 10. It should therefore be clear that the combustion chamber 40 is suitably constructed for the temperature, composition and flow required for the process, and can be of a single unit or multiple unit configuration for proper and efficient production of hot gas for use in the pre-heating of the raw material.
  • the hot gas generator 40 typically comprises the necessary fans, gas lines, gas control safety and control gear, instruments, ducts and vessel so constructed to withstand the desired process demands.
  • the fuel used in the hot gas generator 40 to produce the hot gas is the off-gas produced by the DC arc furnace 12 of the same system 10.
  • a combustion air supply 42 is fed into the hot gas generator 40 for use in the combustion process.
  • the system 10 of the invention includes an optional secondary fuel supply 44 supplying fuel to the hot gas generator 40.
  • the secondary fuel supply 44 could provide fuel in the form of a liquid fuel, liquid petroleum gas, methane gas or similar fuel.
  • the secondary fuel is typically used during start-up of the hot gas generator 40 or to supplement the primary fuel supply, i.e. the supply of off-gas, as and when required. It is also envisaged that waste gas could be provided to the hot gas generator from a gas network on the ferrochrome production plant or facility.
  • An optional secondary air supply 46 is also provided to supplement the air supply into the hot gas generator 40.
  • the hot gas is supplied to at least one preheater.
  • the hot gas is supplied to a heat exchange plant 48.
  • the hot gas generator is preferably located in close proximity to the heat exchange plant 48 to minimise heat losses while conveying the hot gas. Insulated ducting is used to minimise heat losses while conveying the hot gas from the hot gas generator to 40 to the heat exchange plant 48.
  • the heat exchange plant 48 includes at least one and preferably a number of preheater units 50.
  • Each preheater unit 50 includes a heat exchanger 52 for heating raw material using the hot gas.
  • the heat exchangers 52 are cross flow or counter flow heat exchangers.
  • the heat exchangers 52 are of the tube or plate type heat exchangers.
  • the heat exchangers 52 are shell and tube heat exchangers in which the raw material is conveyed in tubes 52.1 of the heat exchangers and the hot gas is supplied into an internal volume 52.4 of the heat exchanger 52 surrounding the tubes, i.e. the volume around the tubes as defined by a shell 52.2 of the heat exchanger 52.
  • Parallel, spaced apart baffles 52.3 extend from the shell 52.2 into the internal volume 52.4 and secure the tubes 52.1 in position while directing the flow of hot gas within the shell.
  • the heat exchangers 52 are constructed to withstand the duties imposed on them by the abrasive nature of the raw material passing on one side and the hot gas passing on the other side of the heat exchanger elements, i.e. the tubes 52.1 in the illustrated embodiment.
  • the raw material is conveyed to the individual preheater units 50 where it is fed into the preheater unit using raw material feeding means.
  • the raw material enters the unit through an inlet located at the top of the heat exchanger 52 into the area known as a feed hopper (not shown).
  • the raw material can be fed to the feed hoppers as continuous streams or in batches.
  • the raw material is supplied from a raw material handling plant 54 where the raw material is prepared, particularly weighed off and blended, according to the requirements of the ferrochrome production process.
  • the prepared raw material is conveyed to the at least one preheater unit 50, in particular the heat exchange plant 48, by way of conveyances 56.
  • the raw material is accumulated in a buffer 58 located at the top of each preheater unit 50 from where it is fed into the heat exchanger 52.
  • the raw material moves along the tubes 52.1 of the heat exchanger 52, i.e. downward, under the force of gravity.
  • the hot gas enters the heat exchanger 52 through an inlet or port located vertically below the inlet of the raw material.
  • the hot gas inlets are located at the bottom of the heat exchanger 52. In this configuration, the hot gas and raw material move in substantially opposite directions through the heat exchanger 52.
  • the hot gas inlet is arranged to provide effective flow patterns around the heat exchanger elements.
  • the raw material in the heat exchanger tubes 52.1 is substantially a packed bed and, as such, is able to conduct heat on a particle-to-particle basis.
  • the hot gas is cooled down as it flows across the heat exchanger elements and heat is conducted to the raw material.
  • the cooled hot gas is discharged through exhaust ducting 60 provided and arranged to dispose of the cooled gas stream safely.
  • the dust and/or fumes extraction system 62 is typically in fluid connection with the feed hopper.
  • the dust and/or fumes extracted through the extraction system 62 is to be cleaned and discharged in a separate, freestanding system.
  • the raw material heated by the hot gas i.e. the heated raw material
  • the heated raw material is accumulated or collected in collection containers, preferably in discharge hoppers 64, located below the heat exchanger elements.
  • the discharge hoppers 64 are illustrated as bottom discharge hoppers through which the heated raw material is discharged. As mentioned above, the raw material moves vertically down the preheater units 50 and accumulate in the discharge hoppers 64. In each preheater unit 50 the discharge hopper 64 forms a bottom section or floor of the preheater unit.
  • the discharge hoppers 64 are insulated to reduce heat losses from the heated raw material. In use, the heated raw material is drawn from the discharge hopper 64 either as a continuous stream or in batches.
  • the raw material in the preheater units 50 is therefore automatically replenished through the discharge and charge process described above. In other words, the raw material is automatically fed into the preheater units 50 based on the discharge of raw material from the preheater units 50.
  • the system 10 includes adjusting means (not shown) for automatically adjusting feeding parameters of the raw material into the preheater unit 50 in response to extraction parameters of the heated raw material from the preheater unit 50.
  • the feeding and extraction parameters could include parameters such as the weight, speed, rate, volumetric rate, temperature, composition, moisture content or any other relevant parameter of the raw material at the point of feeding and extracting raw material to and from the preheater unit 50 respectively.
  • the adjusting means is typically controlled by the control system
  • Extraction of the heated raw material from the preheater units 50, in particular the discharge hoppers 64, is controlled according to the demands of the DC arc furnace 12. Sufficient volume of raw material at ambient temperature is maintained in the buffer 58 at the top of the heat exchanger 52 to provide continuous feed of material to the heat exchanger as the heated raw material is drawn off.
  • a metering system 66 is located below the preheater units 50 for controlling the extraction of raw material from the preheater units.
  • the metering system 66 includes suitable mechanical, electrical and control devices provided to ensure that the raw material is accurately extracted from the preheater units 50 according to the demands of the DC Arc furnace.
  • the metering system 66 further includes weighing means for weighing the raw material during extraction and feeding means 68 for feeding the extracted raw material to the DC arc furnace 12.
  • the feeding means 68 includes pipes or chutes 70 through which the heated raw material is conveyed to the DC arc furnace 12, which are arranged specifically for stability in the electrical circuit 16.
  • the extraction, weighing and feeding of heated raw material occur in an enclosed and airtight arrangement, which is preferably insulated against heat losses and/or against the ingress of air so as to mitigate the risk of combustion of the raw material.
  • the words extracting and extraction, and their derivatives should be interpreted broadly to describe any action of removing, taking out or discharging irrespective of whether such action is by force or not.
  • the heated raw material may be extracted from the preheater unit(s) (50) under external force or simply be allowed to exit from the preheater unit(s) freely, such as under the force of gravity only.
  • the system 10 of the invention includes a control system (not shown) for controlling operations.
  • the objective of the control system is to execute the ferrochrome production process continuously while maintaining affective extraction of ferrochrome from the raw material provided.
  • the control system typically forms part of a plant control system used in controlling operations of the ferrochrome plant.
  • the control system includes sensors for sensing the raw material levels, including the discharge rates of the heated raw material from the preheater unit(s), and in response thereto feed fresh raw material into the feed hoppers.
  • the temperature of the raw material is also continuously monitored as the raw material moves through the preheater units 50.
  • the raw material temperatures are continuously communicated to the control system.
  • the control system includes field instrument devices, electronic signal collection devices, electronic processing units and associated equipment required for efficient control of the ferrochrome production plant as a whole or as subdivisions of the whole.
  • the control system includes monitoring and/or measuring devices installed in strategic locations throughout the system 10, including in the hot gas ducting used to convey hot gas from the hot gas generator 40 to the preheater units 50, the buffers 58 and discharge hoppers 64.
  • the monitoring and/or measuring devices communicate the status information and control inputs to the control system to maintain operating parameters and safety limits.
  • the temperature of the hot gas is continuously monitored and adjusted automatically according to process control parameters. These parameters may include operational parameters to ensure the optimal performance of the DC arc furnace and/or limits imposed by the process and equipment to ensure safe operation of the system 10. This includes using the control system to control operations of the hot gas generator 40 and the heat exchange plant 48 to provide hot gas at the desired temperature, humidity and chemical composition.
  • temperature setpoints are set via the control system and the volume of off-gas and the air-to-fuel ratio in the hot gas generator 40 are controlled in order to meet the requirements of the preheater units 50, and particularly the heat exchangers 52.
  • the control system not only controls the hot gas temperature in accordance with temperature setpoints and limits, but also controls the composition, in particular the amount of oxygen, in the hot gas stream.
  • the operational parameters of the hot gas generator are automatically adjusted by adjusting means (not shown) in order to adjust hot gas properties such as the temperature, humidity and chemical composition of the hot gas.
  • the control system furthermore contains process control logic required for the safe start-up, shut down, emergency shut down and ramp up curves as required by the ducting, equipment or raw material used in the system 10.
  • An advantage of the system 10 in accordance with the invention is that there is no direct contact between the raw material and the hot gas being used to preheat the raw material. As a result there is no mixing of the raw material and hot gas. Heat is transferred in the heat exchanger(s) 52 from the hot gas to the raw material through conduction. As a result of the type of heat exchanger(s) 52 being used, the hot gas transfers heat by conduction to the heat exchanger elements which, in turn, transfer heat to the raw material descending on the opposite side of the heat exchange elements by conduction. It should be clear that the heat exchanger(s) 52 define discrete flow paths for the raw material and the hot gas through them respectively such that there is no direct contact between the raw material and the hot gas. In the system 10 of the invention, conduction is the primary heat exchange mechanism in the preheating of raw material.
  • the preheater units 50 provide buffer stock of raw material and preheats the raw material, to an elevated and controlled temperature, without direct contact between the raw material and the hot gas.
  • the system 10 and the corresponding process for producing ferrochrome products in accordance with the invention address the disadvantages of the known systems and processes set out above. It is envisaged that, in the system 10, the improved electrical efficiency will result in increased production per unit electrical input, while avoiding at least some of the drawbacks of the known preheating techniques. It is believed that the system 10 and process in accordance with the invention have additional benefits, including a reduction in equipment count, reduced opportunity for oxidation in the feed material, avoidance of the consequences of oxidation in accurate temperature control and furnace feed control.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Furnace Details (AREA)

Abstract

L'invention concerne un procédé de préchauffage de matière première dans la production de produits en ferrochrome. Le procédé comprend l'extraction de gaz de rejet produits dans un four à arc à courant continu (12), l'acheminement des gaz de rejet extraits dans un générateur de gaz chaud (40) et la génération de gaz chaud à l'aide des gaz de rejet en tant que source de carburant dans le générateur de gaz chaud (40). Le gaz chaud et la matière première sont introduits dans ladite unité de préchauffage (50) et transportés le long de trajets distincts de sorte qu'il n'y a pas de contact direct entre le gaz chaud et la matière première. Le procédé comprend le chauffage de la matière première dans l'unité de préchauffage (50) au moyen d'une conduction à l'aide du gaz chaud et l'extraction de la matière première chauffée de l'unité de préchauffage (50) pour une utilisation dans le four à arc à courant continu (12). L'invention concerne également un système (10) de préchauffage de la matière première.
PCT/IB2023/052249 2022-03-11 2023-03-09 Système et procédé de préchauffage de matière première dans la production de produits en ferrochrome WO2023170622A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
ZA202202936 2022-03-11
ZA2022/02936 2022-03-11

Publications (1)

Publication Number Publication Date
WO2023170622A1 true WO2023170622A1 (fr) 2023-09-14

Family

ID=86052182

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2023/052249 WO2023170622A1 (fr) 2022-03-11 2023-03-09 Système et procédé de préchauffage de matière première dans la production de produits en ferrochrome

Country Status (1)

Country Link
WO (1) WO2023170622A1 (fr)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA1173650A (fr) * 1980-09-02 1984-09-04 Frederick J. Nelson Methode et dispositif de prechauffage d'une matiere pulverulente avant son introduction dans un four de fonderie
CN209588733U (zh) * 2019-01-27 2019-11-05 中钢集团吉林机电设备有限公司 用于直流矿热炉热装料的炉料多级分离加热装置

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA1173650A (fr) * 1980-09-02 1984-09-04 Frederick J. Nelson Methode et dispositif de prechauffage d'une matiere pulverulente avant son introduction dans un four de fonderie
CN209588733U (zh) * 2019-01-27 2019-11-05 中钢集团吉林机电设备有限公司 用于直流矿热炉热装料的炉料多级分离加热装置

Similar Documents

Publication Publication Date Title
US4270740A (en) Apparatus for producing molten iron by submerged combustion
US4238226A (en) Method for producing molten iron by submerged combustion
US4045214A (en) Method for producing steel
CN102105608B (zh) 锌粉生产方法及设备
JPH06509051A (ja) 乾燥泡立ち流動床における炭素燃焼によるフライアッシュの選別
US5185032A (en) Process for fluidized bed direct steelmaking
NO339763B1 (no) Fremgangsmåte og anlegg for transport av finkornet tørrstoff.
EP2576845B1 (fr) Procédé et usine de production de métal chaud
PT99638B (pt) Processo para a producao de gusa ou de ferro poroso
JP2011525608A (ja) 銑鉄を生産するための熔融還元システム用プロセスガス高純度化装置
US20150135899A1 (en) Method and device for introducing fine particle-shaped material into the fluidised bed of a fluidised bed reduction unit
CN103069023A (zh) 从电炉粉尘回收金属的方法和装置
JPH04502648A (ja) 複式溶解炉における鉄および鋼の製造並びに固体状態オキサイドけんだく物予備還元機
JPS59205576A (ja) 金属材料装入物の融解炉
JPH06172835A (ja) 鉄鉱石の還元方法及びその装置
GB2032594A (en) Hot discharge direct reduction furnace
US4248626A (en) Method for producing molten iron from iron oxide with coal and oxygen
KR100241616B1 (ko) 용융 선철 또는 강 시제품의 제조방법 및 이를 수행하기 위한 플랜트
WO2023170622A1 (fr) Système et procédé de préchauffage de matière première dans la production de produits en ferrochrome
JPH10338513A (ja) 木炭及び活性炭の製造装置
US2307459A (en) Metallurgical process
US20110094337A1 (en) Steelmaking facility comprising a direct reduction plant and an electric-arc furnace
JPS605633B2 (ja) コ−クス化室への装入石炭の計量装置
CZ16898A3 (cs) Způsob výroby tekutého surového železa nebo polotovarů pro výrobu oceli a také zařízení k provádění tohoto způsobu
US3601381A (en) Gas sampling device

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 23717635

Country of ref document: EP

Kind code of ref document: A1

DPE1 Request for preliminary examination filed after expiration of 19th month from priority date (pct application filed from 20040101)