Combination system for steel production and method for operating combination system
By introducing hydrogen recovery and chemical plants into the integrated steel production plant, and utilizing water-gas shift reaction and carbon capture technology, the problem of high carbon dioxide emissions has been solved, enabling the plant to operate stably and sustainably, and reducing its carbon footprint.
Patent Information
- Application Number
- CN202480019151.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-03-16
- Filing Date
- 2024-03-08
- Publication Date
- 2025-11-04
AI Technical Summary
Existing steel production processes have high carbon dioxide emissions and a large carbon footprint, and the operation of these plants is not stable or sustainable.
By introducing a hydrogen recovery plant and a chemical plant into an integrated chemical plant, carbon monoxide in blast furnace gas is converted into hydrogen using a water-gas shift reaction. The hydrogen is then recovered and utilized in the chemical plant. Combined with carbon capture and storage technology, carbon dioxide emissions are reduced. At the same time, the gas stoichiometry is adjusted through a mixing device to achieve efficient gas utilization.
It reduced carbon dioxide emissions, improved the stability and sustainability of the factory, achieved closed-loop energy utilization, and reduced dependence on external energy sources.
Smart Images
Figure CN120898005A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present invention relates to an integrated chemical plant for steel production and a method of operating the integrated chemical system. BACKGROUND
[0002] The integrated chemical plant for steel production comprises a blast furnace for pig iron production, a basic oxygen furnace (BOF) steelmaking plant for crude steel production, an interconnection system for gases produced during the pig iron production and / or during the crude steel production, and a chemical plant connected to the gas pipeline system. In the chemical plant, chemical products can be produced using the provided gas streams, which contain components of the end products, respectively.
[0003] In the blast furnace, pig iron is produced from iron ore, additives such as coke, and other reducing agents such as coal, oil, gas, biomass, recycled waste plastics or other carbon- and / or hydrogen-containing substances. Products inevitably generated in the reduction reaction include carbon monoxide (CO), carbon dioxide (CO2), and in particular hydrogen (H2) and water vapor. The blast furnace top gas (also referred to as top gas and / or blast furnace gas) drawn from the blast furnace process and the above-mentioned components, usually have a high nitrogen content and can contain impurities. The gas content and composition of the blast furnace top gas vary depending on the raw materials and the mode of operation. However, in general, the blast furnace top gas contains nitrogen (N2) in a volume fraction of 35% to 60%, carbon monoxide (CO) in a volume fraction of 20% to 30%, carbon dioxide (CO2) in a volume fraction of 20% to 30%, and hydrogen (H2) in a volume fraction of 2% to 15%. Of the blast furnace top gas produced during pig iron production, approximately 30% to 40% is usually used to heat the hot blast required for the blast furnace process in hot blast stoves; the remaining top gas can be externally utilized, for example, for heating or power generation in other parts of the plant.
[0004] In the basic oxygen furnace steelmaking plant connected downstream of the blast furnace process, pig iron is converted into crude steel. By blowing oxygen into the liquid pig iron, harmful impurities such as carbon, silicon, sulfur, and phosphorus are removed. Due to the large amount of heat generated by the oxidation process, scrap steel is usually added up to 25% of the weight of the pig iron as a coolant. In addition, lime for slagging and alloying additives are added. The basic oxygen furnace gas discharged from the steelmaking vessel contains a large amount of carbon monoxide (CO) and contains nitrogen (N2), hydrogen (H2), and carbon dioxide (CO2). A typical basic oxygen furnace gas composition has a volume fraction of 50% to 70% carbon monoxide (CO), 10% to 20% nitrogen (N2), about 15% carbon dioxide (CO2), and about 2% hydrogen (H2). This basic oxygen furnace gas is either flared or, in modern steel plants, captured and transported to an energy utilization system.
[0005] The integrated chemical plant can optionally be operated in combination with a coking plant. In this case, the aforementioned integrated chemical plant also comprises a coke oven plant, in which coal is converted into coke by a coking process. The coking of coal produces coke oven gas, which is rich in hydrogen and contains appreciable amounts of methane (CH4). A typical coke oven gas contains 55 to 70 vol% hydrogen (H2), 20 to 30 vol% methane (CH4), 5 to 10 vol% nitrogen (N2) and 5 to 10 vol% carbon monoxide (CO). In addition, the coke oven gas also contains certain proportions of carbon dioxide (CO2), ammonia (NH3) and hydrogen sulfide (H2S). In practical applications, the coke oven gas is used, for example, for heating various parts of the plant and for power generation in a power generation process. In addition, it is known that coke oven gas can be used together with blast furnace top gas or basic oxygen furnace gas for the production of synthesis gas.
[0006] In an integrated metallurgical plant operated in combination with a coking plant, about 40 to 50% of the three raw gases obtained, namely blast furnace top gas, basic oxygen furnace gas and coke oven gas, are used in the chemical process. About 50 to 60% of the generated gas is sent to a power plant for power generation. The electricity generated in the power plant can meet the electricity demand for pig iron and crude steel production. Ideally, the energy balance is closed, i.e. no additional energy input is required in addition to the iron ore as raw material and carbon in the form of coal and coke as an energy source, and no other products leave the integrated plant in addition to crude steel and slag.
[0007] A problem in the prior art is the high carbon dioxide (CO2) emissions, in particular a large carbon footprint.
[0008] Against this background, the object of the present application is to improve the sustainability of the overall process and the carbon dioxide (CO2) balance, in particular to reduce carbon dioxide (CO2) emissions, to reduce the carbon footprint, while at the same time achieving a stable, continuous and sustainable operation of the plant. SUMMARY
[0009] The above object is achieved by the integrated plant for steel production according to claim 1 and the method for operating an integrated plant according to claim 8.
[0010] The invention provides an integrated chemical plant for steel production, comprising: a blast furnace for pig iron production; a basic oxygen converter steel plant for crude steel production; a blast furnace gas pipeline system for gases obtained during pig iron production; an interconnection system for gases obtained during pig iron production and / or during crude steel production, in particular comprising carbon-containing gases (such as CO-containing gases, CO2-containing gases or combinations thereof); a hydrogen recovery plant; a chemical plant, wherein the chemical plant is connected to the interconnection system; a hydrogen pipeline for hydrogen-containing gases (in particular hydrogen) obtained in the hydrogen recovery, wherein the hydrogen pipeline is connected to the interconnection system upstream of the chemical plant in flow direction; a mixing device for hydrogen-containing gases (in particular hydrogen) obtained in the hydrogen recovery and for gases produced during pig iron production and / or during crude steel production, which mixing device is arranged downstream of the hydrogen recovery plant and upstream of the chemical plant in flow direction, in particular connected to the interconnection system, for mixing the gases obtained during pig iron production and / or during crude steel production with the hydrogen-containing gases (in particular hydrogen) obtained in the hydrogen recovery, for example to adjust the stoichiometric ratio of the gas components in the interconnection system before the gases enter the chemical plant, wherein the blast furnace gas pipeline system is connected to the hydrogen recovery plant as an input pipeline into the hydrogen recovery plant and the hydrogen pipeline is connected to the hydrogen recovery plant as an output pipeline from the hydrogen recovery plant.
[0011] The present application also provides a method of operating an integrated chemical plant for steel production, the plant comprising: a blast furnace for pig iron production; a basic oxygen converter steel plant for crude steel production; a blast furnace gas pipeline system for gases obtained during pig iron production; an interconnection system for gases obtained during pig iron production and / or during crude steel production, in particular comprising carbon-containing gases (such as CO-containing gases, CO2-containing gases or combinations thereof); a hydrogen recovery plant; a chemical plant, wherein the chemical plant is connected to the interconnection system; a hydrogen pipeline for hydrogen-containing gases (in particular hydrogen) obtained in the hydrogen recovery, wherein the hydrogen pipeline is connected to the interconnection system upstream of the chemical plant in flow direction; a mixing device for hydrogen-containing gases (in particular hydrogen) obtained in the hydrogen recovery and for gases produced during pig iron production and / or during crude steel production, wherein the mixing device is located downstream of the hydrogen recovery plant and upstream of the chemical plant in flow direction, in particular connected to the interconnection system, in particular for mixing the gases produced during pig iron production and / or during crude steel production with the hydrogen-containing gases (in particular hydrogen) obtained in the hydrogen recovery, for example to establish a stoichiometric ratio of the gas components in the interconnection system before the gases enter the chemical plant; the blast furnace gas pipeline system is connected to the hydrogen recovery plant as an input pipeline into the hydrogen recovery plant, and the hydrogen pipeline is connected to the hydrogen recovery plant as an output pipeline from the hydrogen recovery plant, wherein the mixing device establishes a mixed gas, and the mixing device is in particular for establishing a mixed gas with a stoichiometric mixture, which stoichiometric mixture is obtained by dividing the difference between the molar amount of hydrogen as the dividend and the molar amount of carbon dioxide as the subtrahend by the sum of the molar amount of carbon monoxide and the molar amount of carbon dioxide as the divisor.
[0012] The present application can be implemented in an integrated chemical plant for steel production and a method of operating the integrated chemical plant. The equipment in the integrated chemical plant can be present individually and / or in pairs.
[0013] Compared to conventional plant connections, the integrated chemical plant for steel production of the present application has the advantage that carbon monoxide present in the blast furnace gas can be converted into hydrogen by means of a water-gas shift reaction, and hydrogen or hydrogen-rich gas for converting carbon-containing gases (such as CO-containing gases, CO2-containing gases or combinations thereof) can be provided from the metallurgical gas in the chemical plant, so that CO and / or CO2 can be chemically bound on a larger volume without the need for external hydrogen provision and CO2 emissions are reduced. The physical recirculation of the blast furnace gas and the recovery of hydrogen from the blast furnace gas results in a higher utilization efficiency of the blast furnace gas than is conventionally the case in the conversion of blast furnace gas into electrical energy in a power plant.
[0014] The method of operating the integrated chemical plant according to the present application has the advantage compared to conventional methods that in addition to recovering hydrogen or recovering the synthesis gas converted in the chemical plant, CO2 is separated which can be converted in the chemical plant or otherwise utilized by carbon capture and utilization or carbon capture and storage, thereby reducing CO2 emissions. DETAILED DESCRIPTION
[0015] In the chemical plant, chemical products can be produced from the provided gas streams, which contain components of the end product, respectively. The chemical products can be, for example, methanol or higher alcohols, or other hydrocarbon compounds. The production performance, in particular the throughput, of the chemical plant is controlled by the volume of gas supplied to the chemical plant. A major challenge for the chemical plant is the dynamic mode of operation at different loads, which is stabilized by the integrated chemical plant according to the present application / the method of operating according to the present application. The mode of operation at different loads can be achieved by having a large number of small units connected in parallel to the chemical plant and individually starting / stopping these units depending on the amount of available utilizable gas. For example, different chemical products can also be produced in one or more units.
[0016] For producing hydrocarbon compounds, such as methanol or higher alcohols, it is necessary to provide a gas mixture consisting essentially of carbon monoxide (CO) and / or carbon dioxide (CO2) and hydrogen (H2), which contains the carbon monoxide and / or carbon dioxide and hydrogen components in the correct proportions. The hydrogen source used can be blast furnace gas and / or basic oxygen furnace gas and / or coke oven gas; additional hydrogen can be produced by converting the CO content by means of a water-gas shift reaction. Other hydrogen sources are also available, in particular water electrolysis. Carbon monoxide (CO) can be provided, for example, by basic oxygen furnace gas. Blast furnace top gas and / or basic oxygen furnace gas can be used, for example, as a source of carbon dioxide (CO2).
[0017] In the context of the present application, a hydrogen recovery plant is a device for hydrogen production, in particular a device capable of providing hydrogen, such as a water-gas shift reaction plant, in particular a device for converting the CO content by means of a water-gas shift reaction (CO + H2O <== > CO2 + H2), or a device for hydrogen removal, in particular a hydrogen separation membrane plant, or a combination thereof.
[0018] In a further embodiment of the present application, the hydrogen recovery plant is a water-gas shift reaction plant and / or a hydrogen separation membrane plant; in particular the hydrogen separation membrane plant is located downstream of the water-gas shift reaction plant in the flow direction.
[0019] In a further embodiment of the present application, the hydrogen recovery plant further comprises a first CO2 removal plant, in particular a CO2 scrubbing device, wherein the first CO2 removal plant is located upstream of the hydrogen separation membrane plant in flow direction and the first CO2 removal plant is connected to the interconnection system via a first CO2 conduit, in particular the first CO2 conduit is connected to the interconnection system upstream of the mixing device for hydrogen containing gas in flow direction.
[0020] In a further embodiment of the present application, the integrated chemical plant further comprises a first CO2 splitter for carbon dioxide obtained from the first CO2 removal plant, wherein the first CO2 splitter is connected to the first CO2 conduit.
[0021] In a further embodiment of the present application, the integrated chemical plant further comprises at least one controllable gas distribution device, in particular an operatively controlled gas distribution device, for distributing the blast furnace gas stream supplied to the blast furnace gas conduit system and the interconnection system, in particular the controllable gas distribution device is arranged between the blast furnace gas conduit system and the interconnection system. Preferably, the blast furnace gas stream is distributed between the blast furnace gas conduit system and the interconnection system by the gas distribution device such that after the chemical conversion of the gas stream in the blast furnace gas conduit system in the hydrogen production plant, the resulting hydrogen stream or hydrogen containing substance stream is mixed with the gas stream from the interconnection system in the mixing device, thereby generating a mixed gas having a stoichiometric mixing quotient in the range of 1 to 10, preferably in the range of 1.2 to 6, more preferably in the range of 1.8 to 4, most preferably in the range of 1.9 to 3, wherein the stoichiometric mixing quotient is obtained by dividing the difference between the molar amount of hydrogen as the dividend and the molar amount of carbon dioxide as the subtrahend by the sum of the molar amount of carbon monoxide and the molar amount of carbon dioxide as the divisor.
[0022] In the context of the present application, the mixing device refers to a device for mixing gases and / or liquids with each other. More specifically, the mixing device can be selected from the group consisting of a venturi nozzle, a mixing vessel, a mixing station, a static mixer, an eductor, a pipe T-junction or a combination thereof.
[0023] In a further embodiment of the present application, the integrated chemical plant further comprises a coke oven plant, wherein the coke oven plant is connected to the interconnection system.
[0024] In a further embodiment of the present application, the integrated chemical plant further comprises a biotechnology plant, wherein the biotechnology plant is connected to the interconnection system, in particular downstream of the mixing device for hydrogen containing gas in flow direction.
[0025] In the biotechnological plant, bio-chemical products can be produced using the provided gas streams, which contain components of the end product, respectively. The biological products can be, for example, alcohols (ethanol, butanol), acetone or organic acids. In particular, the biotechnological plant is a fermentation plant, or alternatively a photobiological reaction plant.
[0026] In a further embodiment of the present application, the integrated chemical plant further comprises a second CO2 removal plant, in particular a CO2 scrubbing device, wherein the blast furnace gas duct system is connected to the second CO2 removal plant as an input duct leading into the second CO2 removal plant and a second CO2 duct is connected to the blast furnace gas duct system and / or the interconnection system as an output duct leading out of the second CO2 removal plant, in particular the second CO2 duct is connected to the interconnection system upstream of the mixing device for hydrogen-containing gas in flow direction.
[0027] In a further embodiment of the present application, the integrated chemical plant further comprises a second CO2 splitter for carbon dioxide obtained from the second CO2 removal plant, wherein the second CO2 splitter is connected to the second CO2 duct.
[0028] In a further embodiment of the present application, the integrated chemical plant further comprises at least one blast furnace gas compression plant, in particular a blast furnace gas compression plant, wherein the blast furnace gas compression plant is connected to the blast furnace gas duct system.
[0029] In a further embodiment of the present application, the integrated chemical plant further comprises at least one blast furnace gas purification plant, in particular a blast furnace gas purification plant, wherein the at least one blast furnace gas purification plant is connected to the blast furnace gas duct system.
[0030] In the context of the present application, a blast furnace gas purification plant refers to a device for at least partial removal of components of the blast furnace gas that can have a detrimental effect on the efficiency of downstream process steps. In particular, blast furnace gas purification refers to a single- or multi-stage purification operation, in particular by mechanical separation methods (e.g. separation methods selected from the group of density, particle size, particle inertia, surface wettability, magnetization, electrical mobility, etc.), absorption, catalytic processes or combinations thereof.
[0031] In a further embodiment of the present application, the integrated chemical plant further comprises at least one basic oxygen converter gas compression plant, in particular a basic oxygen converter gas compression plant.
[0032] In a further embodiment of the present application, the integrated chemical plant further comprises at least one basic oxygen converter gas purification plant, in particular a basic oxygen converter gas purification plant.
[0033] In the context of the present invention, a basic oxygen converter gas cleaning plant refers to a device for at least partially removing components of the basic oxygen converter gas which can have an adverse effect on the efficiency of downstream process steps. In particular, basic oxygen converter gas cleaning refers to a single-stage or multi-stage cleaning operation, in particular by mechanical separation methods (e.g. separation methods selected from the group of density, particle size, particle inertia, surface wettability, magnetizability, electrical mobility, etc.), absorption, catalytic processes or combinations thereof,
[0034] In a further embodiment of the present invention, the stoichiometric mixing quotient of the mixed gas formed by the mixing device is obtained by dividing the difference between the molar amount of hydrogen as the minuend and the molar amount of carbon dioxide as the subtrahend as the dividend by the sum of the molar amount of carbon monoxide and the molar amount of carbon dioxide as the divisor, which has a value in the range of 1 to 10, preferably in the range of 1.2 to 6, more preferably in the range of 1.8 to 4, most preferably in the range of 1.9 to 3.
[0035] In a further embodiment of the present invention, the integrated chemical plant further comprises a first CO2 removal plant, in particular a CO2 scrubbing device, wherein the first CO2 removal plant is connected upstream of the hydrogen separation membrane plant in the flow direction, the first CO2 removal plant is connected to the interconnection system via a first CO2 conduit, in particular the first CO2 conduit is connected to the interconnection system upstream of the mixing device for hydrogen-containing gas in the flow direction; and a first CO2 splitter for carbon dioxide obtained from the first CO2 removal plant, wherein the first CO2 splitter is connected to the first CO2 conduit; and / or a second CO2 removal plant, in particular a CO2 scrubbing device, the blast furnace gas conduit system is connected to the second CO2 removal plant as an input conduit into the second CO2 removal plant, and a second CO2 conduit is connected to the blast furnace gas conduit system and / or downstream of the interconnection system as an output conduit from the second CO2 removal plant, in particular the second CO2 conduit is connected to the interconnection system upstream of the mixing device for hydrogen-containing gas in the flow direction; and a second CO2 splitter for carbon dioxide obtained from the second CO2 removal plant, wherein the second CO2 splitter is connected to the second CO2 conduit; wherein the mixing device and / or the first CO2 splitter and / or the second CO2 splitter establish a mixed gas for the chemical plant, in particular the mixed gas entering the chemical plant from the interconnection system, in which mixed gas the molar amount of carbon dioxide, in particular the removed CO2 gas stream, obtained in the mixing device and / or the first CO2 splitter and / or the second CO2 splitter, occupies a molar proportion in the range of 5 mol% to 45 mol%, preferably in the range of 8 mol% to 40 mol%, more preferably in the range of 15 mol% to 35 mol% of the molar amount of CO and CO2 produced from the blast furnace in the pig iron production process. BRIEF DESCRIPTION OF DRAWINGS
[0036] The application is explained below by means of the attached drawings, which show working examples only. The drawings show schematically:
[0037] Figure 1 Simplified block diagram of the integrated chemical plant for steel production according to the application (dashed parts are optional embodiments).
[0038] Figure 1 An integrated chemical plant 1 for steel production according to one embodiment of the application is shown, comprising a blast furnace 2 for pig iron production, a basic oxygen converter steelworks 3 for crude steel production, a blast furnace gas pipeline system 4 for gases obtained in the pig iron production process, an interconnection system 5 for gases obtained in the pig iron production process and / or in the crude steel production process, a hydrogen recovery plant 6, a chemical plant 7. The chemical plant 7 is connected to the interconnection system 5. A hydrogen pipeline 8 for hydrogen-containing gases obtained in the hydrogen recovery is connected to the interconnection system 5 upstream of the chemical plant 7 in the flow direction. A mixing device 9 for hydrogen-containing gases obtained in the hydrogen recovery and for gases obtained in the pig iron production process and / or in the crude steel production process is arranged downstream of the hydrogen recovery plant 6 and upstream of the chemical plant 7 in the flow direction. The blast furnace gas pipeline system 4 is connected to the hydrogen recovery plant 6 as an input pipeline into the hydrogen recovery plant 6, and the hydrogen pipeline 8 is connected to the hydrogen recovery plant 6 as an output pipeline from the hydrogen recovery plant 6.
[0039] The hydrogen recovery plant 6 is shown as a water gas shift reaction device 10 and a hydrogen separation membrane plant 11, 11'.
[0040] A first CO2 removal plant 12 is connected upstream of the hydrogen separation membrane plant 11, 11' in the flow direction, and the first CO2 removal plant 12 is connected to the interconnection system 5 by a first CO2 pipeline 13.
[0041] A first CO2 splitter 14 for carbon dioxide obtained from the first CO2 removal plant 12 is connected to the first CO2 pipeline 13.
[0042] A controllable gas distribution device 15 for distributing the blast furnace gas stream supplied to the blast furnace gas pipeline system 4 and to the interconnection system 5 is arranged between the blast furnace gas pipeline system 4 and the interconnection system 5.
[0043] A coke oven plant 16 is connected to the interconnection system 5.
[0044] A biotechnological plant 17 is connected to the interconnection system 5 downstream of the mixing device 9 for hydrogen-containing gases in the flow direction.
[0045] The blast furnace gas pipeline system 4 is connected to a second CO2 removal plant 18 as an input pipeline into the second CO2 removal plant 18.
[0046] A second CO2 conduit 19 is connected to the blast furnace gas conduit system 4 and the interconnection system 5 as an output conduit leading from the second CO2 removal plant 18.
[0047] A second CO2 splitter 20 for carbon dioxide obtained from the second CO2 removal plant 18 is connected to the second CO2 conduit 19.
[0048] A blast furnace gas compression plant 21 is connected to the blast furnace gas conduit system 4.
[0049] A blast furnace gas purification plant 22 is connected to the blast furnace gas conduit system 4.
[0050] A basic oxygen converter gas compression plant 23 and a basic oxygen converter gas purification plant 24 are connected to the interconnection system 5 downstream of the basic oxygen converter steelmaking plant 3 for the production of crude steel in the flow direction.
[0051] Industrial applicability
[0052] The integrated steel plant of the type described above and the method for operating the integrated steel plant can be used for the production of steel.
[0053] List of reference symbols
[0054] 1 = integrated steel plant
[0055] 2 = blast furnace
[0056] 3 = basic oxygen converter steelmaking plant
[0057] 4 = blast furnace gas conduit system
[0058] 5 = interconnection system
[0059] 6 = hydrogen recovery plant
[0060] 7 = chemical plant
[0061] 8 = hydrogen conduit
[0062] 9 = mixing device
[0063] 10 = water-gas shift reaction plant
[0064] 11, 11'= hydrogen separation membrane plant
[0065] 12 = first CO2 removal plant
[0066] 13 = first CO2 conduit
[0067] 14 = first CO2 splitter
[0068] 15 = controllable gas distribution device
[0069] 16 = coke oven plant
[0070] 17 = biotechnology plant
[0071] 18 = second CO2 removal plant
[0072] 19 = second CO2 conduit
[0073] 20 = second CO2 splitter
[0074] 21 = BFG compression plant
[0075] 22 = BFG purification plant
[0076] 23 = KVG compression plant
[0077] 24 = KVG purification plant
[0078] BFG = blast furnace gas
[0079] KVG = Kovaichy gas
[0080] KOG = coke oven gas
[0081] ____ = mandatory element
[0082] ------ = optional element
[0083] _.._ = reference line of reference symbol
Claims
1. An integrated plant (1) for steel production, comprising: Blast furnace (2) used for pig iron production, Basic oxygen converter steelmaking plant for crude steel production (3), Blast furnace gas pipeline system (4) for the gas obtained in the pig iron production process; Interconnection system for gases obtained in pig iron production and / or crude steel production (5), Hydrogen recovery plant (6), A chemical plant (7), wherein the chemical plant (7) is connected to the interconnection system (5). A hydrogen pipeline (8) for the hydrogen-containing gas obtained during the hydrogen recovery process, wherein the hydrogen pipeline (8) is connected to the interconnection system (5) upstream of the chemical plant (7) in the flow direction. A mixing device (9) for mixing hydrogen-containing gas obtained during hydrogen recovery and gas obtained during pig iron production and / or crude steel production, the mixing device (9) being arranged downstream of the hydrogen recovery plant (6) and upstream of the chemical plant (7) in the flow direction, wherein the blast furnace gas pipeline system (4) is connected to the hydrogen recovery plant (6) as an input pipeline into the hydrogen recovery plant (6), and the hydrogen pipeline (8) is connected to the hydrogen recovery plant (6) as an output pipeline leading out from the hydrogen recovery plant (6).
2. The integrated factory (1) as described in claim 1, characterized in that, The hydrogen recovery plant (6) is a water-gas shift reaction plant (10) and / or a hydrogen separation membrane plant (11, 11'), particularly the hydrogen separation membrane plant (11, 11') being located downstream of the water-gas shift reaction plant (10) in the flow direction.
3. The integrated factory (1) as described in claim 2, characterized in that, The hydrogen recovery plant (6) further includes a first CO2 removal plant (12), wherein the first CO2 removal plant (12) is located upstream of the hydrogen separation membrane plant (11, 11') in the flow direction, and the first CO2 removal plant (12) is connected to the interconnection system (5) via a first CO2 pipe (13), in particular the first CO2 pipe (13) is connected to the interconnection system (5) upstream of the mixing device (9) for hydrogen-containing gas in the flow direction.
4. The integrated factory (1) as described in claim 3, characterized in that, The integrated plant (1) further includes a first CO2 splitter (14) for obtaining CO2 from the first CO2 removal plant (12), wherein the first CO2 splitter (14) is connected to the first CO2 pipeline (13).
5. The integrated plant (1) as described in any one of claims 1 to 4, characterized in that, The integrated plant (1) also includes at least one controllable gas distribution device (15) for distributing the blast furnace gas flow supplied to the blast furnace gas pipeline system (4) and the interconnection system (5), in particular the controllable gas distribution device (15) is arranged between the blast furnace gas pipeline system (4) and the interconnection system (5).
6. The integrated plant (1) as described in any one of claims 1 to 5, characterized in that, The integrated plant (1) further includes a second CO2 removal plant (18), wherein the blast furnace gas pipeline system (4) is connected to the second CO2 removal plant (18) as an input pipeline into the second CO2 removal plant (18), and the second CO2 pipeline (19) is connected to the downstream of the blast furnace gas pipeline system (4) and / or the interconnection system (5) as an output pipeline leading out from the second CO2 removal plant (18). In particular, the second CO2 pipeline (19) is connected to the interconnection system (5) upstream of the mixing device (9) for hydrogen-containing gas in the flow direction.
7. The integrated factory (1) as described in claim 6, characterized in that, The integrated plant (1) further includes a second CO2 splitter (20) for obtaining CO2 from the second CO2 removal plant (18), wherein the second CO2 splitter (20) is connected to the second CO2 pipeline (19).
8. A method of operating an integrated plant (1) for steel production, said integrated plant (1) comprising: Blast furnace (2) used for pig iron production; A basic oxygen converter steelmaking plant (3) for crude steel production; a blast furnace gas pipeline system (4) for gases obtained during pig iron production; an interconnection system (5) for gases obtained during pig iron production and / or crude steel production; a hydrogen recovery plant (6); a chemical plant (7), wherein the chemical plant (7) is connected to the interconnection system (5); and a hydrogen pipeline (8) for hydrogen-containing gases obtained during hydrogen recovery, wherein the hydrogen pipeline (8) is connected to the interconnection system (5) upstream of the chemical plant (7) in the flow direction. A mixing device (9) for mixing hydrogen-containing gas obtained during hydrogen recovery and gas obtained during pig iron production and / or crude steel production, wherein the mixing device (9) is located downstream of the hydrogen recovery plant (6) and upstream of the chemical plant (7) in the flow direction, wherein the blast furnace gas pipeline system (4) is connected to the hydrogen recovery plant (6) as an input pipeline into the hydrogen recovery plant (6), and the hydrogen pipeline (8) is connected to the hydrogen recovery plant (6) as an output pipeline leading out from the hydrogen recovery plant (6). The mixing device (9) forms a mixed gas having a stoichiometric quotient obtained by dividing the difference between the molar amount of hydrogen and the molar amount of carbon dioxide by the sum of the molar amounts of carbon monoxide and carbon dioxide by the sum of the molar amounts of carbon monoxide and carbon dioxide.
9. The method as described in claim 8, characterized in that, The mixed gas formed by the mixing device (9) has a stoichiometric quotient obtained by dividing the difference obtained by subtracting the molar amount of carbon dioxide from the molar amount of hydrogen as the minuend by the divisor by the sum of the molar amounts of carbon monoxide and carbon dioxide as the divisor. The stoichiometric quotient is in the range of 1 to 10, preferably 1.2 to 6, more preferably 1.8 to 4, and most preferably 1.9 to 3.
10. The method of operating the integrated plant (1) as described in any one of claims 8 or 9, wherein, The integrated plant (1) also includes: A first CO2 removal plant (12), wherein the first CO2 removal plant (12) is connected upstream of the hydrogen separation membrane plant (11, 11') in the flow direction, the first CO2 removal plant (12) is connected to the interconnection system (5) via a first CO2 pipe (13), specifically the first CO2 pipe (13) is connected upstream of the mixing device (9) for hydrogen-containing gas in the flow direction to the interconnection system (5), and further includes a first CO2 splitter (14) for CO2 obtained from the first CO2 removal plant (12), wherein the first CO2 splitter (14) is connected to the first CO2 pipe (13), and / or A second CO2 removal plant (18), wherein the blast furnace gas pipeline system (4) is connected to the second CO2 removal plant (18) as an input pipeline into the second CO2 removal plant (18), and a second CO2 pipeline (19) is connected downstream of the blast furnace gas pipeline system (4) and / or the interconnection system (5) as an output pipeline leading out from the second CO2 removal plant (18), particularly the second CO2 pipeline (19) being connected upstream of the mixing device (9) for hydrogen-containing gas in the flow direction to the interconnection system (5), and further comprising a second CO2 splitter (20) for CO2 obtained from the second CO2 removal plant (18), wherein the second CO2 splitter (20) is connected to the second CO2 pipeline (19), characterized in that, The mixing device (9) and / or the first CO2 splitter (14) and / or the second CO2 splitter (20) form a mixed gas for the chemical plant (7), wherein the molar amount of CO2 obtained from the mixing device (9) and / or the first CO2 splitter (14) and / or the second CO2 splitter (20), particularly the molar amount of CO2 gas stream removed, relative to the molar amount of CO2 and CO obtained from the blast furnace (2) in the pig iron production process, is in the range of 5 mol% to 45 mol%, preferably in the range of 8 mol% to 40 mol%, and particularly preferably in the range of 15 mol% to 35 mol%.