Determination method for state of gas adsorption tower, maintenance method for gas adsorption tower, and gas adsorption tower facility

Abstract

To provide a determination method for a state of a gas adsorption tower, enabling the state of the gas adsorption tower to be determined so that appropriate maintenance is performed at a time when the maintenance of the gas adsorption tower is necessary, with a simpler configuration, and to provide a maintenance method for a gas adsorption tower, and a gas adsorption tower facility.SOLUTION: There is provided a determination method for a state of a gas adsorption tower, the gas adsorption tower being used for separating a specific gas component from a mixed gas by a pressure swing adsorption method. The determination method performs: a temperature measurement step of measuring a temperature of an adsorbent unit for each of a plurality of adsorbent units arranged along a flow path of the mixed gas in the gas adsorption tower; a pressure measurement step of measuring a pressure of the gas passing through the adsorbent unit in the flow path; and a determination step of determining the state of the adsorbent unit on the basis of the measured temperature and the determined pressure.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for determining the state of a gas adsorption tower, a method for maintaining a gas adsorption tower, and gas adsorption tower equipment, and more particularly to a method for determining the state of a gas adsorption tower used to separate a specific gas component from a mixed gas by pressure swing adsorption (PSA), a method for maintaining a gas adsorption tower, and gas adsorption tower equipment. [Background technology]

[0002] Conventionally, the PSA method has been used as a method for separating specific gas components contained in a raw material gas (see Patent Document 1). Equipment (hereinafter also referred to as PSA equipment) that separates and recovers specific gas components from a raw material gas (mixed gas) using the PSA method includes a gas adsorption tower filled with an adsorbent. The gas adsorption tower performs a process of adsorbing the specific gas components onto the adsorbent (adsorption phase) and a process of desorbing the adsorbed specific gas components from the adsorbent and recovering them (desorption phase). PSA equipment is usually equipped with multiple gas adsorption towers, and the specific gas components are separated from the raw material gas by operating each gas adsorption tower while alternately switching between the adsorption phase and the desorption phase (see Patent Documents 2 and 3).

[0003] The performance of the adsorbent packed into the gas adsorption tower (specifically, its gas separation characteristics) is determined by the adsorbent's pore size, pore volume, and other characteristics. Meanwhile, if the raw gas supplied to the gas adsorption tower contains organic solvent components, oil, or moisture, these components adhere to the pores of the adsorbent and cannot be removed from the adsorbent during the desorption phase, causing a decrease (deterioration) in the performance of the adsorbent. Therefore, it is necessary to periodically replace all of the adsorbent in the gas adsorption tower with new adsorbent.

[0004] In addition, adsorbents are highly hydrophilic, and the adsorbents located upstream of the gas flow path in the gas adsorption tower are exposed to moisture and oil in the raw gas, so they tend to deteriorate faster than the adsorbents located downstream. As a result, there tends to be a distribution (bias) in the degree of deterioration of the adsorbents within the gas adsorption tower. Despite this, it was necessary to completely replace the adsorbents in the gas adsorption tower every time the adsorbents located upstream deteriorated.

[0005] The structure and use of gas adsorption towers that take into account the distribution (unevenness) of adsorbent deterioration within the adsorption tower have been developed. For example, Patent Document 4 proposes a gas adsorption tower equipped with multiple adsorbent units and a gas distribution method for the adsorption tower. Specifically, the publication discloses a gas adsorption tower in which multiple adsorbent-packed beds, each filled with adsorbent between breathable partition walls such as mesh members, are arranged in series with intervening spaces where no adsorbent is packed, and gas is distributed into the adsorption tower from the top, bottom, or space of the adsorption bed, bypassing the adsorbent-packed bed. It is disclosed that this gas adsorption tower allows periodic switching of the gas flow path within the gas adsorption tower by opening and closing valves on multiple gas pipes, thereby preventing uneven distribution of gas adsorption amount and recovery purity across the entire adsorbent, thereby reducing the frequency of replacement. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 6-144818 [Patent Document 2] Patent Publication No. 2021-122801 [Patent Document 3] Japanese Patent Publication No. 2022-149023 [Patent Document 4] Patent No. 6468995 Summary of the Invention [Problem to be solved by the invention]

[0007] However, even in the adsorption tower equipped with multiple adsorbent units described in Patent Document 4, when replacing the adsorbent in the adsorption tower in a PSA facility where raw gas is constantly flowing, maintenance such as adsorbent replacement must be performed during a short downtime of the constantly operating PSA facility. Furthermore, because gas adsorption towers are generally large, completely replacing the adsorbent in the tower (maintenance work) requires time and effort. In contrast, if the deterioration state of each of the multiple adsorbent units could be individually determined and the need for maintenance could be determined, the condition of the gas adsorption tower could be managed more efficiently. In this case, it is necessary to be able to appropriately determine the deterioration state of each adsorbent unit using a simpler method.

[0008] The present invention has been made to address these problems, and aims to provide a method for determining the state of a gas adsorption tower, a maintenance method for a gas adsorption tower, and gas adsorption tower equipment that are capable of determining the state of a gas adsorption tower with a simpler configuration so that appropriate maintenance can be performed on the gas adsorption tower when it is necessary. [Means for solving the problem]

[0009] The present invention has been made to address the above-mentioned problems and has the following features: That is, the present invention provides a method for determining the state of a gas adsorption tower as set forth in [1] to [4] below, a maintenance method for a gas adsorption tower as set forth in [5] below, and a gas adsorption tower facility as set forth in [6] to [8] below. [1] A method for determining the state of a gas adsorption tower used to separate specific gas components from a mixed gas by pressure swing adsorption, the method comprising the steps of: a temperature measurement step of measuring the temperature of an adsorbent unit for each of a plurality of adsorbent units arranged along a mixed gas flow path in the gas adsorption tower; a pressure measurement step of measuring the pressure of gas that has passed through the adsorbent unit in the flow path; and a determination step of determining the state of the adsorbent unit based on the measured temperature and the measured pressure. [2] A method for determining the state of a gas adsorption tower described in [1], wherein in the pressure measurement step, the pressure of the adsorbent unit is determined as the differential pressure between a first position and a second position located on opposite sides of the adsorbent unit in the flow path, and in the temperature measurement step, the temperature of the adsorbent unit is determined as the amount of temperature fluctuation of the adsorbent between gas adsorption and gas desorption. [3] A method for determining the state of a gas adsorption tower according to [2], wherein in the determination step, if the differential pressure is equal to or greater than a specified value, the adsorbent unit is determined to be in a state of severe degradation, and if the differential pressure is less than the specified value and the temperature fluctuation amount is equal to or less than a specified value, the adsorbent unit is determined to be in a state of mild degradation. [4] The method for determining the state of a gas adsorption tower according to [2], further comprising a second determination step for determining the state of deterioration of each adsorbent unit based on information relating to the appearance of the adsorbent. [5] A maintenance method for a gas adsorption tower used to separate specific gas components from a mixed gas by pressure swing adsorption, comprising the following steps: a temperature measurement step of measuring the temperature of each of a plurality of adsorbent units arranged along the flow path of the mixed gas in the gas adsorption tower; a pressure measurement step of measuring the pressure of the gas that has passed through the adsorbent unit in the flow path; a determination step of determining the state of the adsorbent unit based on the measured temperature and the measured pressure; and a determination step of determining whether or not maintenance is required for each adsorbent unit based on the determination results. [6] A gas adsorption tower facility used to separate specific gas components from a mixed gas by pressure swing adsorption, the gas adsorption tower facility comprising: a plurality of adsorbent units arranged along a flow path of the mixed gas; a thermometer for measuring the temperature of the adsorbent installed in each adsorbent unit; and a pressure gauge for measuring the pressure of the gas passing through the adsorbent unit in the flow path; and a determination device for determining the state of each adsorbent unit based on the measured temperature and pressure. [7] The gas adsorption tower facility according to [6], wherein the determination device determines whether or not maintenance of each adsorbent unit is required based on the determination result. [8] A gas adsorption tower facility according to [6] or [7], which has a housing that houses a plurality of adsorbent units, and the housing has an observation section for each adsorbent unit at a position opposite the adsorbent unit for observing the adsorbent in the adsorbent unit, and the determination device determines the state of each adsorbent unit based on information regarding the appearance of the adsorbent obtained through the observation section. [Effects of the Invention]

[0010] According to the present invention, the state of a plurality of adsorbent units can be appropriately determined for each adsorbent unit. As a result, the labor and time required for maintenance work on the gas adsorption tower can be significantly reduced, and the state of the gas adsorption tower can be managed more efficiently. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic diagram showing the configuration of a gas adsorption tower facility according to one embodiment of the present invention, and the view showing the gas adsorption tower in FIG. 1 is a side cross-sectional view (cross-sectional view taken along II-II in FIG. 2). [Figure 2] FIG. 2 is a top view showing cross section II of the gas adsorption tower of FIG. [Figure 3] FIG. 2 is a side view of the gas adsorption tower of FIG. [Figure 4] 3 is a flowchart showing an example of a method for determining the state of a gas adsorption tower according to one embodiment of the present invention. [Figure 5] 1 is a flow chart showing an example of a maintenance method for a gas adsorption tower according to an embodiment of the present invention. [Figure 6] FIG. 10 is a schematic diagram showing a gas adsorption tower according to a modified example, and is a side view of the gas adsorption tower. DETAILED DESCRIPTION OF THE INVENTION

[0012] A gas adsorption tower system according to one embodiment of the present invention (hereinafter referred to as the present embodiment) will be described below with reference to the accompanying drawings. The embodiment described below is merely an example for facilitating understanding of the present invention and is not intended to limit the present invention. In other words, the present invention can be modified and improved without departing from the spirit and scope of the present invention. Furthermore, the present invention naturally includes equivalents thereof.

[0013] First, the configuration of a gas adsorption tower system according to this embodiment (hereinafter referred to as gas adsorption tower system S) will be described with reference to Figure 1. Note that in the drawings, each component is shown somewhat simplified and schematic to make the explanation easier to understand. Furthermore, the size (dimensions) of each component and the spacing between components shown in each figure differ from the actual ones. In addition, in this specification, "horizontal," "vertical," "orthogonal," and "parallel" include the range of error generally accepted in the technical field of the present invention, and also include states where the state is deviated from strictly horizontal, vertical, orthogonal, and parallel within a range of a few degrees or less. In this specification, the term "up-down direction" refers to the up-down direction of the gas adsorption tower, ie, the vertical direction.

[0014] In the present invention, the "adsorbent" is not particularly limited as long as it can be used in PSA, and for example, zeolite can be used. In the present invention, the "feed gas" is not particularly limited as long as it is a mixed gas that can be used in PSA, and examples thereof include blast furnace gas and coke oven gas. In the present invention, the "specific gas component" is not particularly limited as long as it is a gas component that can be separated from the raw material gas by PSA. Examples include carbon dioxide (CO) gas separated from blast furnace gas and hydrogen (H) gas separated from coke oven gas.

[0015] (Gas absorption tower equipment) The gas adsorption tower facility S is a PSA facility, and as shown in FIG. 1, includes a gas adsorption tower 1 and a maintenance device 2 as a determination device. The maintenance device 2 is made up of a general-purpose computer. The maintenance device 2 may include one or more computers. The computer also includes a CPU as a processor and a memory 26 as a storage device. The computer also includes a program for determining the state of the gas adsorption tower and a program for maintaining the gas adsorption tower.

[0016] <Gas adsorption tower> As shown in FIGS. 1 and 2, the gas adsorption tower 1 includes multiple adsorbent units 3A-3F, a cylindrical housing 4 that houses the multiple adsorbent units 3A-3F, thermometers T1-T6, and pressure gauges P1-P8. Gas pipes 6A and 6B are connected to the top (upper portion) and bottom (lower portion) of the gas adsorption tower 1. The gas flow direction within the gas adsorption tower 1 switches between gas adsorption (hereinafter also referred to as the adsorption phase) and gas desorption (hereinafter also referred to as the desorption phase). Specifically, during the adsorption phase, pressurized raw gas is supplied from the top of the gas adsorption tower 1 through gas pipe 6A, passes through each of the multiple adsorbent units 3, and is discharged from gas pipe 6B at the bottom. During the desorption phase, the pressure within the gas adsorption tower 1 is reduced to desorb specific gas components from the adsorbent A in the adsorbent unit 3, and the desorbed gas is sucked from the bottom of the gas adsorption tower 1 through gas pipe 6B.

[0017] The gas flow direction in the gas adsorption tower 1, both in the adsorption phase and the desorption phase, is not limited to flowing downward from the top of the gas adsorption tower 1. However, if the gas is flowed upward from the bottom of the gas adsorption tower 1, the adsorbent A may be scattered inside the gas adsorption tower 1, which may cause the vacuum pump to clog when reducing the pressure, etc. Therefore, it is preferable to flow the gas downward from the top of the gas adsorption tower 1, particularly in the adsorption phase.

[0018] Furthermore, when zeolite is used as adsorbent A, during the adsorption phase, CO2 (a specific gas component) with a smaller molecular diameter and higher polarity than the pores is adsorbed in large amounts within the pores of the adsorbent near the gas inlet of each adsorbent unit, while impurities (such as N2) are adsorbed in large amounts in adsorbent A near the gas outlet. Zeolite also has the property of adsorbing CO2 more easily than impurities. Therefore, during the desorption phase, if high vacuum is applied from the gas outlet side during the adsorption phase and CO2 is separated and extracted from adsorbent A, impurities that are weakly adsorbed are released quickly and impurities are released slowly, so by capturing CO2 at different times, it is possible to separate and capture high-concentration CO2 excluding impurities.

[0019] The plurality of adsorbent units 3A to 3F are each formed by placing pellet-shaped adsorbent A inside a cylindrically molded metal mesh member, and are arranged vertically along the flow path of the raw material gas inside the casing 4. There are no particular restrictions on the size or weight of each of the adsorbent units 3A to 3F, but from the perspective of portability during maintenance, it is preferable that the weight of each of the adsorbent units 3A to 3F containing adsorbent A be 20 kg or less.

[0020] The housing 4 is a hollow container that houses a plurality of adsorbent units 3A to 3F therein, and extends vertically as shown in Figures 1 and 3. As shown in Figure 1, the housing 4 includes a frame 8 that extends horizontally inside and on which the adsorbent units 3A to 3F are placed, and a guide member 10 that holds the adsorbent units 3A to 3F in the vertical direction. The frame 8 is for horizontally placing the adsorbent units 3A to 3F, and in this embodiment is composed of two rail members that allow the adsorbent units 3A to 3F to slide on the upper surface of the frame 8. The frame 8 is provided in multiple stages (six stages in FIG. 1) in the vertical direction, and the multiple stages of frames 8 are each arranged at different heights on a support member 12 that is provided parallel to the gas flow direction.

[0021] The guide member 10 abuts against each of the adsorbent units 3A to 3F from the outside in the circumferential direction and holds each of the adsorbent units 3 so that the adsorbent units 3A to 3F are arranged in series without any vertical misalignment. This structure forms a gas flow path that prevents any of the adsorbent units 3A to 3F from coming off, thereby suppressing leakage of gas passing through the adsorbent units 3A to 3F. A packing sheet 5 is sandwiched between the guide member 10, which is disposed between two adjacent adsorbent units among the plurality of adsorbent units 3A to 3F, and the lower adsorbent unit of the two adsorbent units. This ensures airtightness between the two members, and more effectively prevents leakage of gas flowing through the plurality of adsorbent units 3A to 3F.

[0022] 3, a side wall 14 of the housing 4 is provided with a plurality of hatches 16 (hinged doors) that allow the adsorbent units 3A to 3F to be inserted and removed. The structure of the hatches 16 is not limited to hinged doors, and may be, for example, sliding doors, as long as the adsorbent units 3A to 3F can be replaced. With such a structure, the adsorbent units 3A to 3F can be individually replaced (exchanged) with new ones. If the gas adsorption tower 1 is a very large piece of equipment, it is preferable for safety reasons that scaffolding or a deck (not shown) be provided around the side wall 14 of the housing 4. In this case, the scaffolding or the deck can be used to open and close the hatch 16 and to insert and remove (replace) the adsorbent units 3A to 3F through the hatch 16.

[0023] Here, the procedure for replacing the adsorbent units 3A to 3F will be described. In the gas adsorption tower 1, first, the hatch 16 at the location where the adsorbent units 3A to 3F that need to be replaced are located is opened, and the adsorbent units 3A to 3F are removed from the guide members 10 and slid on the frame 8 from inside the housing 4 to the outside. The adsorbent units 3A to 3F that need to be replaced are then removed, and a new adsorbent unit 3 is placed on the frame 8 and slid into the housing 4. After that, the new adsorbent units 3A to 3F are placed in an appropriate position within the housing 4 by abutting the guide members 10 from the outside in the circumferential direction. After the new adsorbent units 3A to 3F are placed, the hatch 16 is closed, completing the replacement of the adsorbent units 3A to 3F. By the above procedure, the plurality of adsorbent units 3A to 3F arranged in the housing 4 can be replaced unit by unit, that is, each unit can be replaced independently.

[0024] 1, the pressure gauges P1 to P8 are arranged inside the upstream gas pipe 6A, inside the downstream gas pipe 6B, and at the bottom of each of the adsorbent units 3A to 3F, and constantly measure the pressure at each position during the adsorption phase. In addition, the pressure gauges P1 to P8 are connected to the maintenance device 2 so as to be able to communicate with each other, and pressure data measured by the pressure gauges P1 to P8 is sent to the maintenance device 2.

[0025] The thermometers T1 to T6 are thermocouples and are arranged at the bottom (downstream side in the gas flow path) of each of the adsorbent units 3A to 3F, as shown in Fig. 1. However, the position of the thermometer T is not limited to the bottom of the adsorbent units 3A to 3F, and it may be arranged inside the unit. The thermometer T constantly measures the temperature of the adsorbent A installed in each of the adsorbent units 3A to 3F during the adsorption phase and the desorption phase. The thermometers T1 to T6 are communicably connected to the maintenance device 2, and the temperature data measured by the thermometers T1 to T6 is sent to the maintenance device 2.

[0026] The connection between the thermometers T1 to T6 and the pressure gauges P1 to P8 and the maintenance device 2 is not particularly limited, and may be wired or wireless.

[0027] Next, a method for operating the gas adsorption tower 1 will be described. In the gas adsorption column 1, as in a general method, a specific gas component is separated from the raw material gas by alternately switching between an adsorption phase and a desorption phase. For example, when zeolite is used as adsorbent A to separate and recover CO2 gas (a specific component) from blast furnace gas (raw material gas), the blast furnace gas is passed through a plurality of adsorbent units 3A to 3F in sequence at a gauge pressure of about 50 KPa from gas pipe 6A and then flows out of gas pipe 6B (adsorption phase). As the blast furnace gas with a high concentration of CO2 passes through the plurality of adsorbent units 3A to 3F in sequence, the CO2 is adsorbed by the zeolite and removed, and the CO2 concentration gradually decreases.

[0028] After the adsorption phase is completed, the CO2 adsorbed in the pores of the zeolite is desorbed and recovered by suctioning from the gas pipe 6B and creating a high vacuum inside the gas adsorption tower 1 (desorption phase). The CO2 is desorbed in order, starting from the zeolite installed in the adsorbent units 3A to 3F closest to the lower gas pipe 6B.

[0029] <Maintenance equipment> The maintenance device 2 judges the state of each of the adsorbent units 3A-3F based on data output from the thermometers T1-T6 and the pressure gauges P1-P8, and determines whether maintenance is required for each of the adsorbent units 3A-3F based on the judgment results. In this embodiment, the maintenance device 2 judges the state of each of the multiple adsorbent units 3A-3F for each adsorbent unit, and determines whether maintenance is required for each adsorbent unit. Here, the state of the adsorbent units 3A-3F refers to the deterioration state of the adsorbent installed in the adsorbent units 3A-3F, and more specifically, the degree of deterioration. Regarding the maintenance of the adsorbent units 3A to 3F, if the deterioration of the adsorbent A is severe, the adsorbent unit will be replaced, and if the deterioration of the adsorbent A is mild, the adsorbent A will be regenerated in the adsorbent unit.

[0030] 1, the maintenance device 2 has an analysis unit 18, a determination unit 20, a decision unit 22, a control unit 24, a memory 26, and a display unit 28. The analysis unit 18, determination unit 20, decision unit 22, and display unit 28 of the maintenance device 2 are controlled by the control unit 24. The analysis unit 18, determination unit 20, decision unit 22, and control unit 24 are realized by cooperation between the hardware devices of a computer that constitutes the maintenance device 2 and software implemented in the computer (specifically, a program installed on the computer).

[0031] The analysis unit 18 determines, for each adsorbent unit, the measured pressure of the gas passing through each adsorbent unit 3A-3F based on the pressure data acquired from the pressure gauges P1-P8. Specifically, the analysis unit 18 determines, for each adsorbent unit 3A-3F, the differential pressure (pressure loss) between a first position and a second position located on opposite sides of each adsorbent unit 3A-3F in the gas flow path. The differential pressure in each adsorbent unit 3A-3F is calculated based on the pressures measured at the first and second positions, and is determined as the difference in pressure between the first and second positions. Here, the first and second positions refer to the upstream and downstream positions of each adsorbent unit 3A-3F, respectively, and the specific positions are not particularly limited. For example, the differential pressure in the second adsorbent unit 3B from the top may be determined from the measurement data of the pressure gauges P1 and P3 shown in FIG. 1, or from the measurement data of the pressure gauges P2 and P3. In the case described below, the differential pressure for the target adsorbent unit 3A to 3F (hereinafter also referred to as the target adsorbent unit) for which the differential pressure is to be calculated is calculated from the measurement data of the pressure gauge located upstream of the target adsorbent unit that is closest to the target adsorbent unit, and the measurement data of the pressure gauge located downstream of the target adsorbent unit that is closest to the target adsorbent unit.

[0032] The differential pressure obtained for the target adsorbent unit reflects the deterioration state of the adsorbent A in that unit. More specifically, when dust accumulates between the particles of adsorbent A in the adsorbent units 3A to 3F and causes clogging, the adsorbent A deteriorates and the differential pressure in the adsorbent units 3A to 3F tends to increase. Therefore, the deterioration state of the adsorbent A in that unit can be determined from the differential pressure of the target adsorbent unit.

[0033] Furthermore, the analysis unit 18 determines the temperature of each of the adsorbent units 3A-3F for each adsorbent unit based on the temperature data acquired from the thermometers T1-T6. Specifically, the analysis unit 18 calculates the temperature fluctuation amount between the adsorption phase and the desorption phase for the adsorbent A in each of the adsorbent units 3A-3F. Here, the temperature fluctuation amount corresponds to, for example, the difference between the maximum temperature of the adsorbent A in the adsorption phase and the minimum temperature of the adsorbent A in the desorption phase. Note that the temperatures indicated by the thermometers T1-T6 are the temperatures of the adsorbent units 3A-3F corresponding to the thermometers T1-T6, but these temperatures can be assumed to be the temperatures of the adsorbent A in the units.

[0034] The temperature fluctuation of adsorbent A reflects the deterioration state of the adsorbent A. More specifically, when a specific component gas is adsorbed onto an adsorbent, heat of adsorption is generated, causing the temperature of the adsorbent unit to rise. Meanwhile, when the adsorbed gas is desorbed, the heat of desorption is removed, causing the temperature inside the gas adsorption tower 1 to drop. However, as the adsorbent A deteriorates, it becomes more difficult for the specific component gas to be adsorbed and desorbed by the adsorbent A, and the temperature fluctuation tends to decrease. For example, when zeolite is used as adsorbent A, the temperature of the adsorbent A increases upon adsorption of CO2 and decreases upon desorption. However, when the adsorbent A deteriorates due to excessive adsorption, it becomes more difficult for the adsorbent A's pores to adsorb or desorb gas, and the temperature fluctuation of the adsorbent A decreases accordingly. Therefore, the deterioration state of the adsorbent A in the adsorbent units 3A to 3F can be determined from the temperature fluctuation of the adsorbent A between the adsorption phase and the desorption phase.

[0035] The determining unit 20 determines the state of each of the plurality of adsorbent units 3A to 3F for each adsorbent unit, and in this embodiment, determines the state of each of the adsorbent units 3A to 3F in two stages. Specifically, in the first stage, the determining unit 20 determines the state of deterioration of each of the adsorbent units 3A to 3F based on the differential pressure in each of the adsorbent units 3A to 3F identified by the analyzing unit 18. In addition, in the second stage, the determining unit 20 determines the state of deterioration of each of the adsorbent units 3A to 3F based on the amount of temperature fluctuation in each of the adsorbent units 3A to 3F calculated by the analyzing unit 18.

[0036] In the first stage of judgment, the judgment unit 20 judges whether the differential pressure in each of the adsorbent units 3A to 3F is equal to or greater than a specified value. If the differential pressure is equal to or greater than the specified value, the judgment unit 20 judges that the pores of the adsorbent A in the adsorbent unit being judged are excessively clogged by dust or the like, and that the adsorbent unit is in a severely deteriorated state. Here, the specified value is set in advance for judgment by the judgment unit 20 and is the sum of the differential pressure value in a new adsorbent unit (i.e., the initial value) plus a specified value. The specified value may be determined depending on the type of adsorbent A and the gas to be adsorbed; for example, when carbon dioxide gas is adsorbed by an adsorbent A made of zeolite, it may be approximately 10 kPa. The specified value is stored in the memory 26 of the maintenance device 2.

[0037] The determining unit 20 then performs a second-stage determination for the adsorbent units 3A-3F for which the differential pressure in the first-stage determination was less than a predetermined value. In the second-stage determination, the determining unit 20 determines whether the temperature fluctuation amount (hereinafter simply referred to as the temperature fluctuation amount) between the adsorption phase and the desorption phase of the adsorbent A in the adsorbent unit being determined is equal to or greater than a predetermined value. If the temperature fluctuation amount is equal to or greater than the predetermined value, the determining unit 20 determines that the adsorbent A in the adsorbent unit being determined has excessive moisture adsorbed into its pores, and that the adsorbent unit is in a mildly deteriorated state. The predetermined value is set in advance for the determination by the determining unit 20 and is a value that depends on the type of adsorbent A and the gas to be adsorbed. For example, when carbon dioxide gas is adsorbed by an adsorbent A made of zeolite, it is preferably 2°C. The specified value is stored in the memory 26 of the maintenance device 2.

[0038] The display section 28 is configured by a display or the like, and displays the determination results by the determination section 20, that is, the determination results regarding the states of each of the plurality of adsorbent units 3A to 3F.

[0039] The decision unit 22 decides whether or not maintenance is required for each of the plurality of adsorbent units 3A to 3F, based on the determination result by the determination unit 20. Specifically, the decision unit 22 determines that maintenance is required for the adsorbent units determined to be in a severely deteriorated state in the first-stage determination and for the adsorbent units determined to be in a mildly deteriorated state in the second-stage determination, and determines that maintenance is not required for the other adsorbent units. Furthermore, the determination unit 22 determines the content of maintenance for the adsorbent unit determined to require maintenance. Specifically, for the adsorbent unit determined to be in a severely deteriorated state, the determination unit 22 determines unit replacement as the maintenance, and for the adsorbent unit determined to be in a mildly deteriorated state, the determination unit 22 determines regeneration treatment as the maintenance. The display unit 28 displays the determined necessity of maintenance for each adsorbent unit and the details of the maintenance.

[0040] (Method for determining the state of a gas adsorption tower) Next, a method for determining the state of the gas adsorption tower 1 in this embodiment will be described with reference to Fig. 4. Here, as an example, a method for determining the state of the gas adsorption tower 1 will be described in the case where zeolite is used as the adsorbent A and carbon dioxide gas is separated from blast furnace gas. The flow described below is merely an example, and some steps in the flow may be changed, new steps may be added, or the order in which steps are performed may be rearranged, as long as it does not deviate from the spirit of the present invention.

[0041] The flow for determining the state of the gas adsorption tower 1 proceeds according to the procedure shown in Fig. 4. Specifically, when the supply of blast furnace gas to the gas adsorption tower 1 begins, thermometers T1 to T6 arranged at predetermined positions within the gas adsorption tower 1 begin constantly measuring the temperature of each of the adsorbent units 3A to 3F (S1). The measured temperature data is sent to the maintenance device 2, and the analysis unit 18 of the maintenance device 2 calculates the amount of temperature fluctuation of the adsorbent A between the adsorption phase and the desorption phase for each of the multiple adsorbent units 3A to 3F based on the temperature data acquired from the thermometers T1 to T6 (S2).

[0042] Simultaneously with step S1, pressure gauges P1 to P8, which are disposed upstream and downstream of each of the adsorbent units 3A to 3F in the gas adsorption tower 1, measure the gas pressure (S3). The measured pressure data is sent to the maintenance device 2, and the analysis unit 18 of the maintenance device 2 calculates, for each of the multiple adsorbent units 3A to 3F, the differential pressure (pressure loss) when the gas passes through the adsorbent unit, based on the pressure data acquired from the pressure gauges P1 to P8 during the adsorption phase (S4).

[0043] Next, the determination unit 20 of the maintenance device 2 determines the deterioration state of each of the adsorbent units 3A to 3F for each adsorbent unit based on the differential pressure identified for each adsorbent unit (S5a). Specifically, the determination unit 20 determines whether the differential pressure is equal to or greater than a specified value, and if the differential pressure is equal to or greater than the specified value, determines that the adsorbent A of that adsorbent unit 3A to 3F has excessive blockage of pores due to dust, is in a severely deteriorated state, and is abnormal (YES in S6a).

[0044] Furthermore, for any of the adsorbent units 3A-3F whose differential pressure is less than a specified value, the determination unit 20 determines the deterioration state of that adsorbent unit based on the temperature fluctuation amount identified in step S2 (S5b). Specifically, the determination unit 20 determines whether the temperature fluctuation amount is less than a specified value, and if so, determines that the adsorbent unit 3A-3F has excessive moisture adsorbed into the pores, is in a mildly deteriorated state, and is abnormal (YES in S6b). On the other hand, the adsorbent units 3A to 3F whose differential pressure is less than the specified value and whose temperature fluctuation amount exceeds the specified value are determined not to be in a deteriorated state and to be normal (NO in S6b).

[0045] Next, the determination unit 20 determines whether the determination of all the adsorbent units 3A to 3F has been completed (S7). If the determination has been completed (YES in S7), the determination flow ends, and if not completed, steps S1 to S6 are repeated (NO in S7).

[0046] (Gas adsorption tower maintenance method) Next, a maintenance method for the gas adsorption tower according to this embodiment will be described with reference to FIG. In the gas adsorption tower maintenance method of this embodiment, in addition to the steps in the gas adsorption tower condition determination flow shown in Figure 4, a step (S8) of determining whether maintenance is required for each of the multiple adsorbent units 3A to 3F is further performed.

[0047] Specifically, the determination unit 22 of the maintenance device 2 determines that maintenance is required for the adsorbent units 3A-3F determined to be abnormal in the above determination flow, among the plurality of adsorbent units 3A-3F. Then, the determination unit 22 determines the specific maintenance content for the adsorbent units determined to be in need of maintenance (S8). Specifically, it determines that an adsorbent unit determined to be in a severely deteriorated state should be replaced with a new unit. Furthermore, it determines that a regeneration process of the adsorbent A should be performed for the adsorbent unit determined to be in a mildly deteriorated state.

[0048] The control unit 24 determines whether it has determined whether maintenance is required for all of the adsorbent units 3A-3F and whether the details of the maintenance have been determined for the adsorbent units that require maintenance (S7'). If it has been determined whether maintenance is required for all of the adsorbent units 3A-3F and the details of the maintenance for the adsorbent units that require maintenance (YES in S7'), the processing flow shown in Fig. 5 ends. If it has not been completed, steps S1-S6 and S8 are repeated (NO in S7').

[0049] According to this embodiment, the state of each of the adsorbent units 3A-3F can be appropriately determined based on the temperature and pressure. Furthermore, the necessity of maintenance can be determined for each of the adsorbent units 3A-3F according to the state of deterioration, allowing maintenance to be performed at an appropriate time. Furthermore, the appropriate maintenance content can be determined for each of the adsorbent units 3A-3F. Furthermore, according to this embodiment, it is possible to perform replacement only on the adsorbent units 3A to 3F that need replacement, rather than replacing all of the adsorbent units 3A to 3F arranged in the gas adsorption tower 1. This reduces the time and workload associated with maintenance work.

[0050] Furthermore, if spare adsorbent units 3A to 3F are prepared, the adsorbent A installed in the removed adsorbent units 3A to 3F that require maintenance can be regenerated and replaced offline, which also reduces the downtime of the equipment. Furthermore, by providing a frame 8 and guide members 10 for installing the adsorbent units 3A to 3F in fixed positions, the adsorbent units 3A to 3F can be easily aligned, thereby reducing the time and burden of maintenance work. This also reduces the time the equipment is down. Furthermore, the appropriate replacement timing can be determined from the measurement data.

[0051] Furthermore, according to this embodiment, the deterioration state of the adsorbent A can be determined using the measurements of the pressure gauge P and the thermometer T installed in the gas adsorption tower 1, and the adsorbent units 3A to 3F that require maintenance can be identified, thereby reducing the frequency of maintenance. Furthermore, since the deterioration state of the adsorbent A installed inside the adsorbent units 3A to 3F can be grasped using both the pressure gauges P1 to P8 and the thermometers T1 to T6, maintenance suited to the deterioration state can be performed. Specifically, for adsorbent units 3A to 3F that are slightly deteriorated but not yet to the point of requiring replacement, nitrogen or the like can be supplied into the gas adsorption tower 1 to regenerate the adsorbent A, making it possible to avoid unnecessary replacement work.

[0052] The above describes one embodiment of the method for determining the state of a gas adsorption tower, the method for maintaining an adsorption tower, and the gas adsorption tower equipment of the present invention. However, the above embodiment is merely an example for facilitating understanding of the present invention and does not limit the present invention. In other words, the present invention can be modified and improved without departing from the spirit and scope of the present invention. Furthermore, the present invention naturally includes equivalents thereof.

[0053] As a modified example of the gas adsorption tower equipment S, as shown in Fig. 6, the housing 4 may have an observation unit 30 such as a looking glass at a position facing each of the adsorbent units 3A to 3F. In such a configuration, a camera 32 may be further provided to capture an image of the adsorbent A in each adsorbent unit through the observation unit 30. The image captured by this camera 32 corresponds to information about the appearance of the adsorbent A, such as information about the color and particle size of the adsorbent A. In the gas adsorption tower evaluation method and gas adsorption tower maintenance method according to the above embodiments, the condition of each of the plurality of adsorbent units 3A to 3F may be evaluated for each adsorbent unit based on the image captured by the camera 32, for example, from the color of the adsorbent A in each of the adsorbent units 3A to 3F. With this configuration, the state of the adsorbent units 3A to 3F can be determined based on the appearance of the adsorbent A in addition to the temperature fluctuation and differential pressure, so that it is possible to more accurately determine whether maintenance is required for each of the adsorbent units 3A to 3F. In addition, information on the appearance of adsorbent A is not limited to being obtained by photographing it with camera 23 through observation section 30, but may also be obtained by an operator visually inspecting it and inputting the inspection results via an input device. [Explanation of symbols]

[0054] 1 Gas adsorption tower 2 Maintenance equipment 3A~3F Adsorbent Unit 4. Cabinet 5. Packing sheet 6 Gas Pipes 6A Gas supply (inlet) side piping 6B Gas discharge (outflow) side piping 8 frames 10 Guide member 12 Support member 14 Side wall 16 Hatch 18 Analysis Department 20 Judgment section 22 Decision Section 24 Control Unit 26 memory 28 Display section 30 Observation Section (Looking Glass) 32 Camera A. Adsorbent S Gas adsorption tower equipment T1~T6 Thermometer P1~P8 pressure gauges

Claims

1. 1. A method for determining the state of a gas adsorption tower used to separate a specific gas component from a mixed gas by pressure swing adsorption, comprising: For each of the plurality of adsorbent units arranged along the flow path of the mixed gas in the gas adsorption tower, a temperature measuring step of measuring the temperature of the adsorbent unit; a pressure measuring step of measuring a pressure of the gas that has passed through the adsorbent unit in the flow path; a determining step of determining a state of the adsorbent unit based on the measured temperature and the measured pressure; A method for determining the state of a gas adsorption tower, comprising:

2. In the pressure measuring step, a differential pressure between a first position and a second position located on opposite sides of the adsorbent unit in the flow path is identified as the pressure of the adsorbent unit; In the temperature measurement step, a temperature fluctuation amount of the adsorbent between a gas adsorption time and a gas desorption time is identified as the temperature of the adsorbent unit. The method for determining the state of a gas adsorption tower according to claim 1.

3. In the determination step, If the differential pressure is equal to or greater than a specified value, it is determined that the adsorbent unit is in a severely deteriorated state; If the differential pressure is less than a specified value and the temperature fluctuation amount is equal to or less than a specified value, the adsorbent unit is determined to be in a mildly deteriorated state. The method for determining the state of a gas adsorption tower according to claim 2.

4. and further performing a second determination step of determining a deterioration state of each of the adsorbent units based on information about the appearance of the adsorbent. The method for determining the state of a gas adsorption tower according to claim 2.

5. A maintenance method for a gas adsorption tower used to separate a specific gas component from a mixed gas by pressure swing adsorption, comprising: For each of the plurality of adsorbent units arranged along the flow path of the mixed gas in the gas adsorption tower, a temperature measuring step of measuring the temperature of the adsorbent unit; a pressure measuring step of measuring a pressure of the gas that has passed through the adsorbent unit in the flow path; a determining step of determining a state of the adsorbent unit based on the measured temperature and the measured pressure; a determination step of determining whether or not maintenance of the adsorbent unit is required for each adsorbent unit based on the determination result; A gas adsorption tower maintenance method that performs the above.

6. A gas adsorption tower facility used to separate specific gas components from a mixed gas by pressure swing adsorption, a plurality of adsorbent units arranged along a flow path of the mixed gas; a thermometer for measuring the temperature of the adsorbent installed in each of the adsorbent units; a pressure gauge for measuring the pressure of the gas that has passed through the adsorbent unit in the flow path for each of the adsorbent units; a gas adsorption tower comprising: a determination device that determines the state of each adsorbent unit based on the measured temperature and the measured pressure; A gas adsorption tower facility having:

7. The gas adsorption tower facility according to claim 6 , wherein the determining device determines whether or not maintenance of each of the adsorbent units is required based on the determination result.

8. a housing that houses a plurality of the adsorbent units; the housing includes an observation section for each adsorbent unit, the observation section being located opposite the adsorbent unit and configured to observe the adsorbent in the adsorbent unit; 8. The gas adsorption tower facility according to claim 6, wherein the determining device determines the state of each adsorbent unit based on information about the appearance of the adsorbent obtained through the observation unit.

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