Catalyst state determination method and catalyst state determination device

Abstract

A catalyst state determination method comprises measuring temperatures of a catalyst (15) heated by the generation of hydrocarbons at a plurality of measuring points (PO) in a flow direction of a feedstock in a reactor (12) that generates hydrocarbons by bringing the feedstock containing carbon dioxide and hydrogen into contact with the catalyst (15); and determining the state of the catalyst (15) based on the relationship between the plurality of measuring points (PO) and the temperatures of the catalyst (15) measured at the plurality of measuring points (PO).

Description

Background 1. Technical field

[0001] The invention relates to a catalyst state determination method and a catalyst state determination device. 2. State of the art

[0002] Hydrocarbons are widely used as energy sources and raw materials for chemical products, and most hydrocarbons are produced from fossil fuels. However, burning fossil fuel products increases the concentration of carbon dioxide in the atmosphere, which is considered a cause of global warming. Hydrocarbons can be produced from raw materials that contain carbon dioxide. For example, if hydrocarbons are produced from carbon dioxide contained in factory exhaust gases, a reduction in carbon dioxide emissions can be expected.

[0003] JP 2018-8913A discloses a monitoring method for monitoring the condition of a catalyst used in a methane production reaction in which carbon dioxide and hydrogen react continuously in the presence of a catalyst to produce methane in a reactor. In this monitoring method, the amount of hydrogen introduced into the reactor is increased at predetermined intervals over a predetermined period. The change in the reaction efficiency of the methane production reaction is then measured with each increase in the amount of hydrogen introduced, and the condition of the catalyst is monitored based on this change in reaction efficiency. Brief description

[0004] According to the monitoring procedure described in JP 2018-8913A, it is possible to identify the cause of a decrease in the reaction efficiency of the methane production reaction. However, the conventional monitoring procedure does not allow for the prediction of the future state of the catalyst.

[0005] Therefore, it is an object of the invention to provide a catalyst state determination method and a catalyst state determination device that are capable of determining the state of a catalyst in the future.

[0006] A catalyst state determination method according to the invention comprises measuring the temperatures of a catalyst heated by the generation of hydrocarbons at a plurality of measuring points in the flow direction of a raw material in a reactor that generates hydrocarbons by bringing the raw material containing carbon dioxide and hydrogen into contact with the catalyst. The catalyst state determination method determines the state of the catalyst based on a relationship between the plurality of measuring points and the temperatures of the catalyst measured at the plurality of measuring points.

[0007] The condition of the catalyst can include at least one selected from a group consisting of a deterioration state, a remaining lifetime and a catalyst replacement time.

[0008] The catalyst state determination method can estimate a first peak position in a current operating state, based on the relationship between the numerous measurement points and the catalyst temperatures measured at these points. This is the point at which the catalyst temperature reaches a maximum value in the direction of feedstock flow. The catalyst state determination method can then determine the state of the catalyst based on this first peak position.

[0009] The state of the catalyst can be determined based on a relationship between the first peak position, a second peak position where the temperature of the catalyst reaches a maximum value at the start of catalyst use, and a third peak position where the temperature of the catalyst reaches a maximum value at the time of catalyst replacement.

[0010] The state of the catalyst can be determined based on the first peak position and the catalyst's service life from the second peak position to the first peak position.

[0011] The catalyst state-determining device has an input unit configured to input catalyst temperatures. These temperatures are generated by heating the catalyst through the production of hydrocarbons in a reactor that produces hydrocarbons by bringing a feedstock containing carbon dioxide and hydrogen into contact with the catalyst. The temperatures are measured at a multitude of points along the feedstock flow path. The catalyst state-determining device has a control unit configured to determine the state of the catalyst based on the relationship between the multiple measurement points and the catalyst temperatures measured at these points.

[0012] According to the invention, it is possible to provide a catalyst state determination method and a catalyst state determination device that determine the state of a catalyst in the future. Brief description of the drawings Fig. Figure 1 is a block diagram showing a catalyst state determination device according to an exemplary embodiment. Fig. Figure 2 is a schematic diagram showing a reaction device according to an exemplary embodiment. Fig. Figure 3 is a schematic diagram showing the state of a reactor and a measuring unit according to an exemplary embodiment. Fig. Figure 4 is a curve representing changes in the temperature peak of a catalyst. Fig. Figure 5 is a curve diagram to illustrate a method for calculating the remaining service life and replacement time of a catalyst. Fig. Figure 6 is a flowchart that illustrates a procedure for determining the remaining service life of a catalyst. Fig. Figure 7 is a flowchart that illustrates a procedure for determining the time to replace the catalyst. Description of the exemplary implementations

[0013] Several exemplary embodiments are described below with reference to the drawings. For illustrative purposes, the dimensions in the drawings are exaggerated and may differ from the actual dimensions.

[0014] As in Fig. As shown in Figure 1, a catalyst state determination device 1 according to this embodiment comprises a reactor 10, a measuring unit 20, an input unit 30, a control unit 40, and an output unit 50. The measuring unit 20 and the input unit 30 are electrically connected. The input unit 30, the control unit 40, and the output unit 50 are also electrically connected.

[0015] As in Fig. As shown in Figure 2, reaction device 10 produces hydrocarbons from a raw material containing carbon dioxide and hydrogen. For example, reaction device 10 produces methane from the raw material containing carbon dioxide and hydrogen, as shown in the following reaction formula (1). CO2 + 4H2 → CH4 + 2H2O (1)

[0016] As in Fig. As shown in Figure 2, the reaction device 10 according to this embodiment can comprise a heater 11, a reactor 12, a cooler 13, and a gas-liquid separator 14. The heater 11 heats a raw material that is fed into the reactor 12. The reactor 12 produces hydrocarbons from the raw material containing carbon dioxide and hydrogen. The reactor 12 also produces water vapor as a byproduct. The cooler 13 cools a product containing hydrocarbons and water vapor that is produced in the reactor 12. The gas-liquid separator 14 separates hydrocarbons produced in the reactor 12 from water that is produced in the reactor 12 and condensed in the cooler 13 by cooling.

[0017] As in Fig. As shown in Figure 3, reactor 12 in this embodiment has a reaction tube 16 filled with a catalyst 15. The feedstock thus passes through the reaction tube 16 and comes into contact with the catalyst 15. Therefore, reactor 12 produces hydrocarbons when it brings the carbon dioxide and hydrogen-containing feedstock into contact with the catalyst 15. The carbon dioxide supplied to reactor 12 can include carbon dioxide recovered from power plants or factories. Using such carbon dioxide as a feedstock not only reduces the amount of carbon dioxide emitted by power plants or factories, but also allows for the efficient utilization of the carbon dioxide. The hydrogen supplied to reactor 12 can be obtained using renewable energy sources such as solar, wind, and hydropower.Using this type of hydrogen can reduce carbon dioxide emissions in an overall system.

[0018] Reactor 12 can include a fixed-bed reactor. The fixed-bed reactor can be a single-tube reactor or a multi-tube reactor such as a shell-and-tube reactor. The fixed-bed reactor can include reaction tube 16 and a shell (not shown) containing reaction tube 16. The reaction to produce hydrocarbons from carbon dioxide and hydrogen-containing feedstocks is an exothermic reaction. Therefore, if a heating medium such as oil is passed through the shell, the heat of reaction generated by the production of the hydrocarbons can be removed to accelerate the reaction.

[0019] The hydrocarbons produced in reactor 12 can include an alkane and / or an alkene. These hydrocarbons can be produced by a methanation reaction or a Fisher-Tropsch (FT) reaction. The hydrocarbons produced in reactor 12 can be used as sustainable aviation fuel (SAF). The alkane and / or alkene can contain at least one hydrocarbon with 1 to 100 carbon atoms. The alkane and / or alkene can contain at least one hydrocarbon with 1 to 4 carbon atoms. The alkane can, for example, contain at least one alkane selected from a group consisting of methane, ethane, propane, and butane. The alkene can, for example, contain at least one alkene selected from a group consisting of ethylene, propylene, 1-butene, 2-butene, isobutene, and 1,3-butadiene. Methane, ethane, and propane can be used as fuel for town gas.Furthermore, alkenes containing 2 or more and 4 or fewer carbon atoms are useful as raw materials for plastics. The reaction products generated in reactor 12 may contain compounds other than those described above.

[0020] Catalyst 15 can contain at least one catalyst selected from a group consisting of, for example, a nickel catalyst, a ruthenium catalyst, an iron catalyst, and a cobalt catalyst. Catalyst 15 can be selected according to the type of hydrocarbons to be produced. A nickel or ruthenium catalyst can be used in a methanation reaction to produce methane. Iron and cobalt catalysts can be used for FT reactions. Iron catalysts can primarily produce light hydrocarbons, and cobalt catalysts can primarily produce heavy hydrocarbons, including waxes. Iron catalysts can primarily produce alkenes and alkanes, and cobalt catalysts can primarily produce alkanes. Nickel catalysts contain nickel as the active ingredient. Ruthenium catalysts contain ruthenium as the active ingredient.Iron catalysts contain iron as the active ingredient. Cobalt catalysts contain cobalt as the active ingredient. The content of the active ingredient can be 20% by mass or more of the total catalyst.

[0021] The measuring unit 20 measures the temperature of the catalyst 15, which is heated by hydrocarbon production, at a plurality of measuring points PO in a flow direction of the raw material. The measuring unit 20 can have a plurality of temperature sensors. For example, the measuring unit 20 can have a multi-point temperature sensor that has a plurality of thermocouples. The measuring unit 20 can measure the temperature of the catalyst 15 at a plurality of measuring points PO. In this embodiment, the plurality of measuring points PO comprises measuring points PO1 to PO5, and the temperatures of the catalyst 15 are measured at these measuring points. Specifically, the measuring unit 20 measures the current temperature of the catalyst 15 at measuring points PO1 to PO5. However, the number of the plurality of measuring points PO at which the measuring unit 20 measures is not particularly limited. The number of the plurality of measuring points PO can, for example, be four or more.

[0022] The temperatures of catalyst 15, which is heated during the production of hydrocarbons, are measured at multiple measuring points PO in the direction of raw material flow and entered into input unit 30. Specifically, the temperatures at measuring points PO1 to PO5 are measured by measuring unit 20 and entered into input unit 30.

[0023] The controller 40 is a computer comprising a central processing unit (CPU), memory, and an input / output unit. The controller 40 stores a program for determining the state of catalyst 15 and data such as the temperatures at measuring points PO1 to PO5, which are referenced during the program's execution. The controller 40 then determines the state of catalyst 15.

[0024] Catalyst 15 deteriorates over time due to sintering, carbon deposition, and catalyst poisoning, leading to a decrease in its performance. Sintering is a phenomenon in which active metal particles aggregate within the catalyst 15 when it is used at high temperatures, reducing the specific surface area of ​​the active metal and thus decreasing its performance. Carbon deposition is a phenomenon in which hydrocarbons produced from the carbon dioxide-containing feedstock cover the surface of the active metal in the catalyst 15, also resulting in a decrease in its performance.Catalyst poisoning is a phenomenon in which a catalyst poison, such as sulfur, contained in the raw material impairs the chemical action of the active material, leading to a decrease in the performance of the catalyst 15.

[0025] Fig. Figure 4 is a curve representing changes in the temperature peak of catalyst 15, which is heated by hydrocarbon production. As in Fig. As shown in Figure 4, the reaction to produce hydrocarbons from the carbon dioxide-containing feedstock is an exothermic reaction, and the temperature of catalyst 15 rises due to the heat generated in the reaction. At the start of catalyst 15's use in year 0, the temperature peak is located upstream of catalyst 15. This may be because, at the start of catalyst 15's use, the reaction occurs mainly upstream of catalyst 15, where the concentration of the reaction feedstock is high. However, as catalyst 15's use progresses, the temperature peak shifts downstream.This may be because the performance of catalyst 15 on the upstream side deteriorates due to sintering, carbon deposition, catalyst poisoning or the like, and the area where the reaction mainly occurs shifts to the downstream side.

[0026] In the catalyst state determination device 1 according to this embodiment, the control unit 40 therefore determines the state of the catalyst 15 based on the relationship between the plurality of measuring points PO and the temperatures of the catalyst 15 measured at the plurality of measuring points PO. As described above, the temperature peak of the catalyst 15 shifts towards the downstream side of the catalyst 15 as its service life increases. Therefore, the state of the catalyst 15 can be determined based on the relationship between the plurality of measuring points PO and the temperatures of the catalyst 15.

[0027] Fig. Figure 5 is an explanatory diagram illustrating a procedure for calculating a replacement time for the catalyst 15. Fig. 5. A first peak P1 represents the current temperature of catalyst 15; a second peak P2 represents the temperature peak at the start of catalyst 15 use; and a third peak P3 represents the temperature peak at catalyst 15 replacement time. Fig. In section 5, the current service life of catalyst 15 is given by Tc; the time at the start of the service life of catalyst 15 is given by Ts=0; and the time at which catalyst 15 needs to be replaced is given by Te. Fig. 5 is a peak of the first peak P1, designated as a first peak PT1; a peak of the second peak P2, designated as a second peak PT2; and a peak of the third peak P3, designated as a third peak PT3. In Fig. 5 is the position of the first peak PT1, designated as first peak position Xc; the position of the second peak PT2, designated as second peak position Xs; and the position of the third peak PT3, designated as third peak position Xe. Peak here refers to the point where the temperature is highest among the peaks. The peak position refers to the position of catalyst 15 at the peak in the direction of feedstock flow.

[0028] Each peak can be derived from the current temperatures of catalyst 15, which are measured by measuring unit 20 at the multiple measuring points PO. Each peak can be obtained by estimating a point where the temperature is highest among the peaks. The first peak position Xc, for example, can be determined as a position where the temperature of catalyst 15 reverses from an upward trend to a downward trend from an upstream to a downstream side of the catalyst 15. Each peak position can be obtained by determining the peak position within each peak. The second peak P2 can be a temperature peak at the start of catalyst 15 use, for which the first peak P1 was measured.However, if the same type of catalyst 15 is used and the transition of the same or a similar peak is shown, the second peak P2, obtained by measurement with a different batch of catalyst 15, can be used. The third peak P3 is a temperature peak at a catalyst 15 exchange point, so it cannot be measured at the present time. Therefore, the third peak P3 is a previously measured temperature peak at a catalyst 15 exchange point, where the catalyst shows the transition of the same or a similar peak.

[0029] The current remaining lifetime of catalyst 15 is calculated using the following formula (1): Remaining life(%)=(Xe−Xc) / (Xe−Xs)×100

[0030] In mathematical formula (1), Xc is the first peak position, Xs is the second peak position, and Xe is the third peak position. The remaining lifetime of catalyst 15 is assumed to be 100% at the beginning of its use and 0% at the time of replacement.

[0031] As can be seen from the mathematical formula (1), the current remaining lifetime of catalyst 15 can be determined based on the first peak position Xc. Specifically, the current remaining lifetime of catalyst 15 can be determined based on the first peak position Xc, the second peak position Xs, and the third peak position Xe.

[0032] As described above, the controller 40 can estimate the first peak position Xc, at which the temperature of the catalyst 15 in the direction of raw material flow is at its maximum value in the current operating state, based on the relationship between the multitude of measurement points PO and the temperatures of the catalyst 15 measured at the multitude of measurement points PO. Then, based on the first peak position Xc, the controller 40 can determine the state of the catalyst 15.

[0033] Specifically, the controller 40 can determine the state of the catalyst 15 based on the relationship between the first peak position Xc, the second peak position Xs (where the temperature of the catalyst 15 is at its maximum at the start of its use), and the third peak position Xe (where the temperature of the catalyst 15 is at its maximum at the time of catalyst replacement). In the mathematical formula (1) above, the current remaining lifetime of the catalyst 15 is determined using the first peak position Xc, the second peak position Xs, and the third peak position Xe. However, the current state of the catalyst 15 can be roughly understood if the first peak position Xc is known. Therefore, the state of the catalyst 15 can be determined based on only the first peak position Xc.

[0034] The replacement time of catalyst 15 can be calculated using the mathematical formula (2) below. Te=Tc+(Tc−Ts)×(Xe−Xc) / (Xc−Xs)

[0035] In the mathematical formula (2) above, Te is the exchange time (or exchange period) of catalyst 15; Ts is the time at which catalyst 15 began to be used; and Tc is the current usage time of catalyst 15. Furthermore, Xc is the first peak position; Xs is the second peak position; and Xe is the third peak position.

[0036] As can be seen from the mathematical formula (2) above, the current replacement time of catalyst 15 can be determined based on the second peak position Xc. Specifically, the current replacement time of catalyst 15 can be determined based on the first peak position Xc, the second peak position Xs, the third peak position Xe, the current service life Tc of catalyst 15, the time Ts at the start of use of catalyst 15, and a replacement time Te of catalyst 15.

[0037] Thus, the controller 40 can determine the state of the catalyst 15 based on the first peak position Xc and the service life of the catalyst 15 from the second peak position Xs to the first peak position Xc. It should be noted that the controller 40 can determine the replacement time Te of the catalyst 15, similarly to how it determines the current remaining service life of the catalyst 15, based on the first peak position Xc.

[0038] The output unit 50 outputs data indicating the state of the catalyst 15, which is received from the controller 40. The output unit 50 can output at least one state selected from a group consisting of a deterioration state, a remaining service life, and a replacement time for the catalyst 15. The state of the catalyst 15 output by the output unit 50 can be displayed on a display device, such as a monitor (not shown).

[0039] In this embodiment, the controller 40 estimates the first peak PT1 of the first peak P1 and determines the state of the catalyst 15 based on the first peak position Xc. However, the controller 40 can determine that the catalyst 15 has degraded if the measurement point with a temperature higher than a threshold value is among the plurality of measurement points PO downstream of a predetermined measurement point. Therefore, it is not strictly necessary to use the first peak PT1.

[0040] Next, with reference to the flowchart in Fig. 6 a procedure for determining the remaining lifetime of catalyst 15 is described.

[0041] In step S1, the controller acquires 40 temperatures of the catalyst 15, which are measured by the measuring unit 20 at the multitude of measuring points, and an input via the input unit 30.

[0042] In step S2, for example, the controller 40 estimates the first peak position Xc. In addition to the first peak position Xc, the controller 40 can also estimate the second peak position Xs.

[0043] In step S3, the controller 40 determines a state of the catalyst 15 based on the first peak position Xc. The controller 40 determines the remaining lifetime of the catalyst 15 based on, for example, the first peak position Xc, the second peak position Xs, and the third peak position Xe. Specifically, the controller 40 determines the remaining lifetime of the catalyst 15 based on the mathematical formula (1) above.

[0044] Next, with reference to the flowchart in Fig. 7 a procedure for determining a replacement time of the catalyst 15 is described.

[0045] First, the controller 40 receives temperatures similar to step S1 above and estimates a peak position in step S2.

[0046] In step S4, the controller 40 determines a state of the catalyst 15 based on the first peak position Xc. The controller 40 determines a replacement time for the catalyst 15 based, for example, on the first peak position Xc and the service life of the catalyst 15. Specifically, the controller 40 determines the replacement time of the catalyst 15 based on the mathematical formula (2).

[0047] This embodiment describes the method for determining the remaining service life and replacement time of the catalyst 15 using the controller 40. However, based on the first peak position Xc of the catalyst 15, a deterioration state of the catalyst 15 can be determined by an indicator of the deterioration state, such as a degree of deterioration or a deterioration progress of the catalyst 15. Therefore, the state of the catalyst 15 can comprise at least one element selected from a group consisting of the deterioration state, the remaining service life, and the replacement time of the catalyst 15.

[0048] Next, the operation and effect of the catalyst state determination device 1 according to this embodiment will be described.

[0049] A catalyst state determination method comprises measuring the temperatures of the catalyst 15, heated by the generation of hydrocarbons, at a plurality of measuring points PO in the flow direction of a feedstock in the reactor 12, which generates hydrocarbons by bringing the feedstock containing carbon dioxide and hydrogen into contact with the catalyst 15. The catalyst state determination method determines the state of the catalyst based on the relationship between the plurality of measuring points PO and the temperatures of the catalyst 15 measured at the plurality of measuring points PO.

[0050] The catalyst state-determining device 1 has an input unit 30 for inputting temperatures of the catalyst 15 heated by the generation of hydrocarbons in the reactor 12, which generates hydrocarbons by bringing a feedstock containing carbon dioxide and hydrogen into contact with the catalyst 15, wherein the temperatures are measured at a plurality of measuring points in the direction of flow of the feedstock. The catalyst state-determining device 1 has a control unit 40 for determining the state of the catalyst 15 based on the relationship between the plurality of measuring points PO and the temperatures of the catalyst measured at the plurality of measuring points PO.

[0051] The temperature peak of catalyst 50 shifts over the service life of catalyst 15 in the direction of raw material flow. Therefore, the controller 40 can determine the state of catalyst 15 based on the temperatures at the numerous measuring points located in the raw material flow direction. Using the catalyst state determination method and the catalyst state determination device 1, a future state of the catalyst can be determined.

[0052] For example, the actual state of deterioration of the catalyst 15 varies, even in the case of a catalyst 15 with a fixed two-year replacement cycle, depending on the operating conditions of the catalyst 15, and therefore the catalyst does not necessarily reach its service life in two years. However, with the catalyst state determination method and the catalyst state determination device 1 according to this embodiment, the future state of the catalyst can be determined, so that the catalyst 15 can be used beyond the replacement point, depending on its condition.

[0053] The state of catalyst 15 can comprise at least one group selected from a deterioration state, remaining lifetime, and replacement time of catalyst 15. With this configuration, the deterioration state, remaining lifetime, and replacement time can be determined, enabling efficient use of catalyst 15 and reducing its operating costs.

[0054] Based on the relationship between the multitude of measurement points PO and the temperatures of catalyst 15 measured at these points, the controller 40 can estimate the first peak position Xc at which the temperature of catalyst 15 reaches its maximum value in the direction of raw material flow. The state of catalyst 15 can then be determined based on this first peak position Xc. By estimating the first peak position Xc and determining the state of catalyst 15 based on its location, the current state of catalyst 15 can be more accurately determined.

[0055] The condition of catalyst 15 can be determined based on the relationship between the first peak position Xc, the second peak position Xs (where the catalyst temperature is at its maximum at the start of use), and the third peak position Xe (where the catalyst temperature is at its maximum at the time of replacement). This configuration allows for a more precise determination of the condition of catalyst 15, such as its remaining service life. Therefore, catalyst 15 can be used more efficiently, and its operating costs can be further reduced.

[0056] The condition of catalyst 15 can be determined based on the first peak position Xc and the service life of catalyst 15 from the first peak position Xs to the first peak position Xc. With this configuration, the condition of catalyst 15, such as the replacement time, can be determined more accurately. Therefore, catalyst 15 can be used more efficiently, and its operating costs can be further reduced.

[0057] The entire content of Japanese patent application 2024-174774 (filed on October 4, 2024) is incorporated herein by reference.

[0058] Several exemplary embodiments have been described above. However, these embodiments can be modified based on the disclosure above. All components of the exemplary embodiments above and all features described in the claims can be individually extracted and combined, provided they are consistent with each other.

[0059] The invention can, for example, contribute to Goal 13 of the United Nations Sustainable Development Goals (SDGs): Urgent action to mitigate climate change and its impacts. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2018 - 8 913 A [0003, 0004] JP 2024-174774

[0057]

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