Purification system

Abstract

Reduce the energy consumption when purifying methane. [Solution] The purification system S is provided in a pipeline 101 through which a gas containing methane flows and includes a supply unit 110 that supplies ozone to the gas, and a catalyst 120 provided inside the pipeline 101 that purifies methane in an ozone atmosphere. The supply unit 110 has an electrode that generates ozone by discharging when a voltage is applied, and the catalyst 120 is heated by the heat generated by the discharge of the electrode. The catalyst 120 is provided downstream of the electrode in the flow direction of the gas flowing through the pipeline 101 and within a predetermined distance from the electrode.

Description

Technical Field

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[0001] The present invention relates to a purification system for purifying methane.

Background Art

[0002] A catalyst for decomposing methane, which is an air pollutant, in an ozone atmosphere is known. Patent Document 1 discloses a technique for purifying methane by heating a gas containing methane and ozone in a heating unit to 100° C. or higher and then bringing it into contact with a catalyst in which iron is supported on silica, zeolite, or the like.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the technique of Patent Document 1, it is necessary to heat a gas containing methane and ozone to 100° C. or higher in a heating unit. Therefore, energy is consumed to heat the gas containing methane and ozone.

[0005] Therefore, the present invention has been made in view of these points, and an object thereof is to reduce the energy consumption when purifying methane.

Means for Solving the Problems

[0006] In an aspect of the present invention, there is provided a purification system including a supply unit provided in a pipeline through which a gas containing methane flows and configured to supply ozone to the gas, and a catalyst provided in the pipeline and configured to purify the methane in an ozone atmosphere, the supply unit having an electrode configured to generate the ozone by discharging when a voltage is applied, and the catalyst being heated by heat generated by the discharging of the electrode.

[0007] The catalyst may be provided downstream of the electrode in the flow direction of the gas through the pipeline, and within a predetermined distance from the electrode.

[0008] The electrode is composed of two or more needle-shaped electrodes, and each of the two or more needle-shaped electrodes may be provided in the conduit such that its longitudinal direction is perpendicular to the flow direction.

[0009] The electrode comprises a first electrode having a plurality of needle-shaped electrodes and a base to which each needle-shaped electrode is connected, and a second electrode having a plurality of needle-shaped electrodes and a base to which each needle-shaped electrode is connected, wherein each of the plurality of needle-shaped electrodes of the first electrode and the second electrode is provided perpendicular to the base, the longitudinal direction of each of the plurality of needle-shaped electrodes of the first electrode and the second electrode is perpendicular to the flow direction, the surfaces on which the needle-shaped electrodes are provided of the base of the first electrode and the base of the second electrode face each other, and one of the needle-shaped electrodes of the first electrode and one of the needle-shaped electrodes of the second electrode may be positioned alternately in a plane perpendicular to the flow direction.

[0010] The catalyst may be provided on the surface of the electrode.

[0011] The electrode comprises a conductive layer of metal and an insulating layer covering the conductive layer, and the catalyst may be provided on the surface of the insulating layer.

[0012] The electrode is composed of a plurality of plate-shaped electrodes, and the catalyst may be provided on the opposing surfaces of the plurality of plate-shaped electrodes that face each other.

[0013] The electrode comprises a first electrode having a plurality of plate-shaped electrodes and a base to which the sides of each plate-shaped electrode are connected, and a second electrode having a plurality of plate-shaped electrodes and a base to which the sides of each plate-shaped electrode are connected, wherein each of the plurality of plate-shaped electrodes of the first electrode and the second electrode is provided perpendicular to the base, and the first electrode and the second electrode are provided such that the surfaces on which the plate-shaped electrodes are provided of the base of the first electrode and the base of the second electrode face each other, the longitudinal direction of the base is parallel to the flow direction of the gas, and one of the plate-shaped electrodes of the first electrode and one of the plate-shaped electrodes of the second electrode are positioned alternately.

[0014] The electrodes may be provided such that their longitudinal direction is parallel to the flow direction of the gas through the pipeline. [Effects of the Invention]

[0015] According to the present invention, the energy consumption during methane purification can be reduced. [Brief explanation of the drawing]

[0016] [Figure 1] This is a diagram illustrating the configuration of the purification system S. [Figure 2] This is a diagram illustrating the configuration of the supply unit. [Figure 3] This is a diagram to explain the methane purification rate. [Figure 4] This is a flowchart illustrating an example of a methane purification process. [Figure 5] This is a diagram illustrating two opposing comb-shaped electrodes. [Figure 6] This is a diagram illustrating the purification system according to the second embodiment. [Figure 7] This is a diagram illustrating the disassembled parts. [Figure 8] This is a schematic diagram of one plate-shaped electrode when the system is composed of three or more plate-shaped electrodes. [Figure 9] This is a schematic diagram of a disassembled section consisting of two electrodes, each having multiple plate-shaped electrodes. [Figure 10] It is a schematic diagram of a needle-shaped electrode provided with a catalyst.

Embodiments for Carrying Out the Invention

[0017] <Configuration of Purification System S According to the First Embodiment> FIG. 1 is a diagram for explaining the configuration of the purification system S. The purification system S includes a sensor 102, an intake section 103, a supply section 110, a catalyst 120, an AC power supply 130, and a supply control device 200. The purification system S has a function of purifying methane contained in a gas. The purification system S adds ozone to the gas containing methane and causes ozone and methane to react on the catalyst, thereby decomposing methane to generate water and nitrogen dioxide. In the following description, decomposing methane to generate water and nitrogen dioxide may be referred to as purifying methane.

[0018] A gas to be purified containing methane flows through the pipeline 101. The gas to be purified containing methane is, for example, the atmosphere. A sensor 102 is provided in the pipeline 101. The sensor 102 detects the amount of methane in the gas. For example, the sensor 102 detects the methane concentration in the gas to be purified. The sensor 102 outputs the detected methane concentration to the supply control device 200.

[0019] The intake section 103 is, for example, an intake fan. The intake section 103 sucks the gas to be purified into the pipeline 101. The intake section 103 is provided on the downstream side of the sensor 102 in the pipeline 101. In FIG. 1, the intake section 103 sucks the gas to be purified so that the gas to be purified flows from left to right in the z direction in the pipeline 101.

[0020] The supply section 110 is provided downstream of the intake section 103 in the pipeline 101. The supply section 110 supplies ozone to the gas to be purified. The supply section 110 generates ozone by discharge and supplies the generated ozone to the gas to be purified. Hereinafter, the configuration of the supply section 110 will be described with reference to FIG. 2. FIG. 2 is a diagram for explaining the configuration of the supply section 110.

[0021] The supply unit 110 has a first needle-type electrode 111 and a second needle-type electrode 112 that discharge and generate ozone when a voltage is applied. The first needle-type electrode 111 and the second needle-type electrode 112 are covered with a dielectric or insulator. The dielectric or insulator can be ceramic, glass, rubber, etc. In the following description, when it is not necessary to distinguish between the first needle-type electrode 111 and the second needle-type electrode 112, they will be referred to as needle-type electrodes.

[0022] The first needle-type electrode 111 and the second needle-type electrode 112 are provided separated by a predetermined distance P. The distance P is the distance at which a discharge can occur between the first needle-type electrode 111 and the second needle-type electrode 112 when a voltage is applied between them. The specific value of the distance P is 0.1 mm or more and 10 mm or less. The predetermined distance is preferably 0.5 mm or more and 5 mm or less. It is even more preferable that the predetermined distance is 1 mm or more and 2 mm or less.

[0023] The needle-shaped electrodes are positioned within the conduit 101 such that their longitudinal direction is perpendicular to the flow direction (z-direction) of the gas to be purified within the conduit 101. For example, the needle-shaped electrodes are positioned so that their longitudinal direction lies within a plane parallel to the xy-plane. Furthermore, each of the two needle-shaped electrodes is positioned within the same plane. Specifically, the longitudinal direction of the needle-shaped electrodes is positioned parallel to the x-direction in the xy-plane, but it may also be positioned parallel to the y-direction. Note that the longitudinal direction of the needle-shaped electrodes can be in any orientation within the xy-plane as long as it is perpendicular to the z-direction.

[0024] Two needle-shaped electrodes are connected to an AC power supply 130. The AC power supply 130 applies an AC voltage to each of the two needle-shaped electrodes. For example, the AC power supply 130 applies an AC power capable of causing a discharge between the two needle-shaped electrodes. Specifically, the AC power supply 130 applies an AC voltage of, for example, 1kV or more and 1kHz or higher to the needle-shaped electrodes. More specifically, when the AC power supply 130 causes a silent discharge between the needle-shaped electrodes, it applies an AC voltage of 10kV or more and a frequency of 1kHz or more and 100kHz or lower to the needle-shaped electrodes. Alternatively, when the AC power supply 130 causes a creepage discharge on the surface of the needle-shaped electrodes, it may apply an AC voltage of 1kV or more and 10kV or lower and a frequency of 1kHz or more and 10kHz or lower to the needle-shaped electrodes.

[0025] When a discharge occurs between the two needle-shaped electrodes, the electrons generated by the discharge collide with oxygen molecules contained in the gas to be purified flowing between and around the two needle-shaped electrodes. One oxygen molecule that is hit by an electron separates into two oxygen atoms. Then, ozone is generated when the oxygen atoms and oxygen molecules combine. In this way, the supply unit 110 supplies the ozone generated by the discharge to the gas to be purified flowing between and around the two needle-shaped electrodes.

[0026] The catalyst 120 is provided downstream of the supply unit 110 in the flow direction (z-direction) in which the gas to be purified flows through the pipeline 101. The catalyst 120 has a carrier of a predetermined structure and a coating layer supported on the surface of the carrier. The predetermined structure is, for example, a honeycomb structure, a corrugated structure, a mesh structure, or a porous structure. The material of the carrier is, for example, cordierite, silicon carbide, aluminum titanate, stainless steel, iron-chromium-aluminum alloy, glass wool, glass fiber, or titanium. The coating layer includes, for example, zeolite, iron ion exchange zeolite, or cobalt ion exchange zeolite. The surface area of ​​the carrier may include areas that do not support the coating layer.

[0027] Catalyst 120 purifies methane in an ozone atmosphere. Catalyst 120 decomposes methane by reacting ozone with methane on its surface, producing water and carbon dioxide. As the gas to be purified passes through catalyst 120, the methane is purified, resulting in a purified gas with a lower methane content than the original gas. The purified gas is discharged through pipeline 101. In this way, the purification system S can purify the air by drawing in air containing methane, purifying the methane, and then discharging it.

[0028] The methane purification rate of catalyst 120 changes with temperature. Figure 3 is a diagram illustrating the methane purification rate. The horizontal axis of Figure 3 shows the temperature of catalyst 120 (corresponding to the temperature of the gas to be purified), and the vertical axis shows the methane purification rate. In Figure 3, catalysts M1, M2, and M3 are shown as types of coating layers for catalyst 120. Catalyst M1 is a cobalt ion exchange zeolite (Co-BEA) in which cobalt is supported on a β-type skeleton structure zeolite. Catalyst M2 is an iron ion exchange zeolite (Fe-BEA) in which iron is supported on a β-type skeleton structure zeolite. Catalyst M3 is a β-type skeleton structure zeolite (BEA). As shown in Figure 3, for catalysts M1 and M2, when the temperature is below 150°C, the methane purification rate increases with increasing temperature. For catalyst M3, when the temperature is below 200°C, the methane purification rate increases with increasing temperature.

[0029] The catalyst 120 is heated by the heat generated when an electrical discharge occurs in the AC power supply 130. The mechanism by which heat is generated by the electrical discharge is explained below. When atoms or molecules in the gas to be purified collide with electrons generated by the electrical discharge, they enter an excited state. The atoms or molecules in the gas to be purified include, but are not limited to, nitrogen molecules, oxygen molecules, carbon dioxide, and noble gases (helium). Heat is generated when the energy released when the excited atoms or molecules return to a stable state is converted into thermal energy. The purification system S heats the catalyst 120 with the heat generated when atoms or molecules in the gas to be purified return from an excited state to a stable state. In this way, the purification system S can heat the catalyst 120 using the heat generated when an electrical discharge occurs in the supply unit 110 without using a heater or the like. Since the power consumption when generating ozone and heat by electrical discharge is less than the power consumption of a heater, the purification system S can reduce the energy consumption when purifying methane compared to when heating is performed by a heater.

[0030] When heating the catalyst 120 with the heat generated by the electrical discharge, the shorter the distance between the supply unit 110 where the discharge occurs and the catalyst 120, the easier it is for the heat generated by the discharge to be transferred to the catalyst 120. For this reason, the catalyst 120 is located within a predetermined distance from the supply unit 110. The predetermined distance is the distance at which the catalyst 120 can be heated to a predetermined temperature or higher by the heat of the electrical discharge. The predetermined temperature is, for example, 50°C, and preferably 80°C. The specific value of the predetermined distance can be determined as appropriate, for example, 100 mm or less. The predetermined distance is preferably 50 mm or less, and even more preferably 10 mm or less. By bringing the supply unit 110 and the catalyst 120 closer together in this way, the heat of the electrical discharge is more easily transferred to the catalyst 120, so the purification system S can easily heat the catalyst 120.

[0031] Incidentally, if the amount of methane in the gas to be purified is high, more ozone needs to be supplied. Also, if the gas to be purified does not contain methane, supplying ozone will waste energy.

[0032] Therefore, the supply control device 200 controls the amount of ozone supplied to the gas to be purified according to the amount of methane contained in the gas to be purified. The supply control device 200 has a storage unit 210 and a control unit 220. The storage unit 210 is a storage medium including ROM (Read Only Memory), RAM (Random Access Memory), and hard disk. The storage unit 210 stores the program to be executed by the control unit 220.

[0033] The control unit 220 is a computing resource that includes a processor such as a CPU (Central Processing Unit). The control unit 220 performs the functions of the acquisition unit 221 and the supply control unit 222 by executing a program stored in the storage unit 210. The acquisition unit 221 acquires the methane concentration detected by the sensor 102. The acquisition unit 221 outputs the acquired methane concentration to the supply control unit 222.

[0034] The supply control unit 222 controls the frequency and voltage value of the AC voltage applied by the AC power supply 130 to the supply unit 110. The supply control unit 222 changes the frequency and voltage value of the AC voltage applied by the AC power supply 130 to the supply unit 110 according to the methane concentration. For example, the supply control unit 222 increases at least one of the frequency and voltage value of the AC voltage applied by the AC power supply 130 to the supply unit 110 as the methane concentration increases. In this way, the more methane contained in the gas to be purified, the more ozone is generated in the supply unit 110, making it easier for ozone and methane to react on the catalyst 120, and improving the methane purification rate.

[0035] Furthermore, the supply control unit 222 does not apply AC voltage from the AC power supply 130 to the supply unit 110 if the methane concentration is below a threshold. The threshold is, for example, the lower limit at which the sensor 102 can detect methane. As a result, the purification system S does not supply ozone to the gas to be purified when there is little methane in the gas to be purified, thus suppressing energy waste.

[0036] [Process to purify methane] Figure 4 is a flowchart illustrating an example of a methane purification process. The acquisition unit 221 acquires the methane concentration (step S1). Specifically, the acquisition unit 221 acquires the methane concentration detected by the sensor 102 and outputs the acquired methane concentration to the supply control unit 222.

[0037] The supply control unit 222 determines whether the methane concentration is above a threshold (step S2). If the methane concentration is above the threshold (Yes in step S2), the supply control unit 222 starts the intake unit 103 (step S3). After the intake unit 103 starts, the supply control unit 222 applies an AC voltage from the AC power supply 130 to the supply unit 110 (step S4). In other words, if the methane concentration is above the threshold, the supply control unit 222 draws in the gas to be purified and supplies ozone to the gas to be purified to purify the methane.

[0038] If the methane concentration is below the threshold (No in step S2), the supply control unit 222 does not apply an AC voltage from the AC power supply 130 to the supply unit 110 (step S5). In other words, if the methane concentration is below the threshold, the supply control unit 222 does not supply ozone to the gas to be purified because there is no need to purify the gas to be purified.

[0039] (Modification 1 of the supply unit 110) The supply unit 110 may have three or more needle-shaped electrodes. The three or more needle-shaped electrodes are arranged such that adjacent electrodes have opposite polarity. Each needle-shaped electrode is connected to the AC power supply 130 such that adjacent needle-shaped electrodes have opposite polarity when an AC voltage is applied.

[0040] (Modification 2 of the supply unit 110) The supply unit 110 may have two opposing comb-shaped electrodes instead of a needle-shaped electrode. Figure 5 is a diagram illustrating two opposing comb-shaped electrodes. In this case, the supply unit 110 has a first comb-shaped electrode 113 and a second comb-shaped electrode 114. The first comb-shaped electrode 113 comprises a plurality of needle-shaped electrodes 113a and a base 113b to which each needle-shaped electrode 113a is connected. Each of the plurality of needle-shaped electrodes 113a of the first comb-shaped electrode 113 is provided perpendicular to the base 113b.

[0041] The configuration of the second comb-shaped electrode 114 is the same as that of the first comb-shaped electrode 113. Specifically, the second comb-shaped electrode 114 comprises a plurality of needle-shaped electrodes and a base to which each needle-shaped electrode is connected. Each of the plurality of needle-shaped electrodes of the second comb-shaped electrode 114 is positioned perpendicular to the base.

[0042] The two comb-shaped electrodes are positioned opposite each other. More specifically, the two comb-shaped electrodes are positioned so that the bases of the two needle-shaped electrodes face each other. More specifically, the two comb-shaped electrodes are positioned so that the surface of the base 113b of the first comb-shaped electrode 113 on which the needle-shaped electrode is attached faces the surface of the base of the second comb-shaped electrode 114 on which the needle-shaped electrode is attached faces each other.

[0043] Each needle-shaped electrode of the two comb-shaped electrodes is positioned perpendicular to the flow direction (z-direction). Specifically, each needle-shaped electrode of the two comb-shaped electrodes is positioned so as to fit within the xy-plane perpendicular to the z-direction. Specifically, each needle-shaped electrode is positioned so that its longitudinal direction is parallel to the x-direction. However, each needle-shaped electrode may also be positioned so that its longitudinal direction is parallel to the y-direction, and it may be oriented in any direction within the xy-plane as long as its longitudinal direction is perpendicular to the z-direction.

[0044] The first comb-shaped electrode 113 and the second comb-shaped electrode 114 are arranged such that one needle-shaped electrode 113a of the first comb-shaped electrode 113 and one needle-shaped electrode of the second comb-shaped electrode 114 are alternately positioned in the xy-plane. Specifically, the two comb-shaped electrodes are arranged with a predetermined gap between them so that the needle-shaped electrodes of each of the two comb-shaped electrodes do not come into contact with each other. The gap is the distance at which a discharge occurs between each needle-shaped electrode. As a result, the gas to be purified is supplied with ozone as it passes around the needle-shaped electrodes of the two comb-shaped electrodes that generate ozone, and becomes a gas to be purified that contains ozone.

[0045] The purification system S can increase the number of discharge points by using a comb-shaped electrode with multiple needle-shaped electrodes. As a result, the purification system S can supply ozone almost uniformly as the gas to be purified passes between each needle-shaped electrode of the comb-shaped electrode.

[0046] [Effects of the purification system S of the first embodiment] As described above, the purification system S of the first embodiment includes a supply unit 110 provided in a pipeline 101 through which a gas to be purified containing methane flows, and which supplies ozone to the gas to be purified, and a catalyst 120 provided in the pipeline 101, which purifies methane in an ozone atmosphere. The supply unit 110 has electrodes that generate ozone by performing a discharge when a voltage is applied, and the catalyst 120 is heated by the heat generated by the discharge of the electrodes. In other words, the purification system S can heat the catalyst 120 with the heat generated by the discharge. Therefore, the purification system S can heat the catalyst 120 with the thermal energy generated when a discharge occurs in the supply unit 110 without using a heater or the like. As a result, the purification system S can reduce the energy consumption when purifying methane.

[0047] <Configuration of the purification system S according to the second embodiment> In the first embodiment of the purification system S, the supply unit 110 and the catalyst 120 were provided separately. However, the supply unit 110 and the catalyst 120 may be provided as a single unit. Figure 6 is a diagram illustrating the purification system S according to the second embodiment. In the second embodiment of the purification system S, instead of the supply unit 110 and the catalyst 120, there is a decomposition unit 160 in which the electrode and catalyst are integrated. In describing the second embodiment, points similar to the purification system S of the first embodiment will be omitted, and points that differ from the purification system S of the first embodiment will be described.

[0048] The decomposition section 160 includes an electrode and a catalyst provided on the electrode. Figure 7 is a diagram illustrating the decomposition section 160. The decomposition section 160 is composed of a plurality of plate-shaped electrodes. Specifically, the decomposition section 160 is composed of a first plate-shaped electrode 161 and a second plate-shaped electrode 162. The first plate-shaped electrode 161 and the second plate-shaped electrode 162 are provided facing each other. The first plate-shaped electrode 161 and the second plate-shaped electrode 162 are provided with a gap P between them. The gap P is the distance at which discharge occurs between the first plate-shaped electrode 161 and the second plate-shaped electrode 162. In the following description, when it is not necessary to distinguish between the first plate-shaped electrode 161 and the second plate-shaped electrode 162, they will be referred to as plate-shaped electrodes.

[0049] The plate-shaped electrodes are positioned so that their longitudinal direction is parallel to the flow direction. In other words, the plate-shaped electrodes are positioned so that their longitudinal direction is parallel to the z-direction. Furthermore, the cross-section of each plate-shaped electrode perpendicular to its longitudinal direction is positioned so that its vertical direction is parallel to the y-direction and its horizontal direction is parallel to the x-direction. However, the cross-section of each plate-shaped electrode perpendicular to its longitudinal direction may be positioned so that its vertical direction is parallel to the x-direction and its horizontal direction is parallel to the y-direction.

[0050] The plate-type electrode includes a conductive layer 301, an insulating layer 302, and a catalyst 303. The conductive layer 301 is shown in white. The conductive layer 301 is a metal such as iron, copper, or gold, but is not limited to metals; any conductive material is acceptable. The insulating layer 302 is provided so as to cover the conductive layer 301. The insulating layer 302 is shown in light gray. The insulating layer 302 is ceramic or glass, but is not limited to these.

[0051] The catalyst 303 is provided on the surface of the insulating layer 302. In other words, the catalyst 303 is provided on the opposing surfaces of the plate-type electrodes. The catalyst 303 is shown in dark gray. The catalyst 303 is provided on both opposing surfaces of the first plate-type electrode 161 and the second plate-type electrode 162. The catalyst 303 may be provided on either the opposing surface of the first plate-type electrode 161 or the second plate-type electrode 162. The catalyst 303 decomposes methane to produce water and carbon dioxide. The catalyst 303 includes at least one of zeolite, iron ion exchange zeolite, and cobalt ion exchange zeolite.

[0052] The first plate-shaped electrode 161 and the second plate-shaped electrode 162 are connected to an AC power supply 130. Specifically, the conductive layer 301 of the plate-shaped electrodes is connected to the AC power supply 130. The AC power supply 130 applies an AC voltage to the plate-shaped electrodes. For example, the AC power supply 130 applies an AC voltage of 10kV and 10kHz to the plate-shaped electrodes. When an AC voltage is applied from the AC power supply 130 to the needle-shaped electrode, a discharge occurs between the two plate-shaped electrodes. When a discharge occurs between the plate-shaped electrodes, heat is generated. The catalyst 303 is heated by the heat generated by the discharge.

[0053] Thus, the purification system S of the second embodiment can heat the catalyst 303 using the thermal energy generated when an electrical discharge occurs, without using a heater or the like. Furthermore, since the catalyst 303 is provided on the surface of the plate-shaped electrode, an electrical discharge occurs on the surface of the catalyst 303. As a result, the purification system S of the second embodiment can heat the catalyst 303 more efficiently than the purification system S of the first embodiment. Consequently, the purification system S can further reduce the energy consumption when purifying methane.

[0054] Furthermore, since the plate-shaped electrodes of the purification system S in the second embodiment are arranged so that their longitudinal direction is parallel to the flow direction, the opportunities for methane and ozone in the gas to be purified to come into contact with the catalyst 303 as the gas to be purified passes between the two plate-shaped electrodes are increased. As a result, the purification system S in the second embodiment is more efficient at purifying methane.

[0055] (Modified example 1 of the disassembled section 160) The decomposition section 160 was composed of a first plate-type electrode 161 and a second plate-type electrode 162, but it may be composed of three or more plate-type electrodes. In this case, the decomposition section 160 has a catalyst 303 on the surface of the plate-type electrodes. Figure 8 is a schematic diagram of a decomposition section 160 composed of three or more plate-type electrodes 163. Each plate-type electrode 163 is composed of a conductive layer 301, an insulating layer 302, and a catalyst 303. The conductive layer 301 is shown in white. The insulating layer 302 is provided so as to cover the conductive layer 301. The insulating layer 302 is shown in light gray. The catalyst 303 is provided so as to cover the insulating layer 302. The catalyst 303 is shown in dark gray.

[0056] When the disassembled section 160 is composed of three or more plate-shaped electrodes 163, each plate-shaped electrode 163 is provided with a predetermined spacing P so as not to come into contact with other plate-shaped electrodes 163. Furthermore, each plate-shaped electrode 163 is provided so that its longitudinal direction is parallel to the z-direction. Each plate-shaped electrode 163 is provided so that the vertical direction in a cross section perpendicular to the longitudinal direction is parallel to the y-direction and the horizontal direction is parallel to the x-direction. However, the plate-shaped electrode 163 may also be provided so that the vertical direction in a cross section perpendicular to the longitudinal direction is parallel to the x-direction and the horizontal direction is parallel to the y-direction.

[0057] By using three or more plate-shaped electrodes, the purification system S can increase the area for ozone generation and the surface area of ​​the catalyst. As a result, the purification system S can generate more ozone and increase the opportunities for methane and ozone to come into contact with the catalyst, thereby improving the methane purification rate.

[0058] (Modified example 2 of the disassembled section 116) The disassembled section 160 may be composed of two electrodes, each having a plurality of plate-shaped electrodes. Figure 9 is a schematic diagram of a disassembled section 160 composed of two electrodes, each having a plurality of plate-shaped electrodes. The disassembled section 160 is composed of a first electrode 117 and a second electrode 118. The first electrode 117 comprises a plurality of plate-shaped electrodes 117a and a base 117b to which the sides of each plate-shaped electrode 117a are connected. Each of the plurality of plate-shaped electrodes 117a is positioned perpendicular to the base 117b. The second electrode 118, similar to the first electrode 117, comprises a plurality of plate-shaped electrodes and a base to which the sides of each plate-shaped electrode are connected. Each of the plurality of plate-shaped electrodes of the second electrode 118 is positioned perpendicular to the base of the second electrode 118.

[0059] The first electrode 117 and the second electrode 118 are arranged so that the surfaces on which the plate-shaped electrodes are attached to the base 117b of the first electrode 117 and the base of the second electrode 118 face each other. Furthermore, the longitudinal direction of the bases of the first electrode 117 and the second electrode 118 are arranged so that the plate-shaped electrodes 117a of the first electrode 117 and the plate-shaped electrodes of the second electrode 118 are positioned alternately. The plate-shaped electrodes 117a of the first electrode 117 and the plate-shaped electrodes of the second electrode 118 are arranged with a gap P between them where discharge occurs.

[0060] (Modified example 3 of the disassembled section 160) The decomposition section 160 may use a needle-type electrode instead of a plate-type electrode. Figure 10 is a schematic diagram of the decomposition section 164 of the modified example 3. The decomposition section 160 has a conductive layer 401 which is a needle-type electrode, an insulating layer 402 covering the conductive layer 401, and a catalyst layer 403 covering the insulating layer 402. Each of the multiple decomposition sections 164 is provided so that its longitudinal direction is parallel to the z direction. Each decomposition section 164 is provided with a gap P between them. Each decomposition section 164 is provided so that they are arranged vertically in the y direction, but they may also be provided so that they are arranged horizontally in the x direction.

[0061] [Effects of the purification system S of the second embodiment] As described above, the purification system S of the second embodiment has a plurality of plate-shaped electrodes that generate ozone by discharging when a voltage is applied, and a decomposition unit 160 that includes a catalyst provided on the electrodes. The catalyst 303 is heated by the heat generated by the discharge of the electrodes. Since the catalyst 303 is provided on the surface of the plate-shaped electrodes, discharge occurs on the surface of the catalyst 303. As a result, the purification system S of the second embodiment can heat the catalyst 303 more efficiently than the purification system S of the first embodiment. Consequently, the purification system S can further reduce the energy consumption when purifying methane.

[0062] Although the present invention has been described above using embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments, and various modifications and changes are possible within the scope of its gist. For example, all or part of the apparatus can be configured by functionally or physically distributing and integrating in any unit. Furthermore, new embodiments resulting from any combination of multiple embodiments are also included in the embodiments of the present invention. The effects of the new embodiments resulting from the combinations are combined with the effects of the original embodiments. [Explanation of symbols]

[0063] S Purification System 101 Pipeline 102 Sensors 103 Intake section 110 Supply section 111 1st needle-shaped electrode 112 Second needle-type electrode 113 First comb-shaped electrode 113a Needle-shaped electrode 113b base 114 Second comb-shaped electrode 117 1st electrode 117a Plate electrode 117b base 118 2nd electrode 120 Catalyst 130 AC power supply 160 Disassembly section 161 1st plate electrode 162 2nd plate electrode 200 Supply control device 210 Storage section 220 Control Unit 221 Acquisition Department 222 Supply Control Unit 301 Conductive layer 302 Insulating layer 303 Catalyst 401 Conductive layer 402 Insulating layer 403 Catalyst layer

Claims

1. A supply unit is provided in a pipeline through which a gas containing methane flows, and which supplies ozone to the gas. A catalyst is provided within the aforementioned pipeline to purify the methane under an ozone atmosphere, It has, The supply unit has an electrode that discharges when a voltage is applied to generate the ozone, The catalyst is heated by the heat generated by the discharge of the electrode. Purification system.

2. The catalyst is provided downstream of the electrode in the flow direction of the gas flowing through the pipeline, and within a predetermined distance from the electrode. The purification system according to claim 1.

3. The electrode is composed of two or more needle-shaped electrodes. Each of the two or more needle-shaped electrodes is provided in the conduit such that its longitudinal direction is perpendicular to the flow direction. The purification system according to claim 2.

4. The electrode is composed of a first electrode having a plurality of needle-shaped electrodes and a base to which each needle-shaped electrode is connected, and a second electrode having a plurality of needle-shaped electrodes and a base to which each needle-shaped electrode is connected. Each of the plurality of needle-shaped electrodes of the first electrode and the second electrode is provided perpendicular to the base, The first electrode and the second electrode are arranged such that the longitudinal direction of each of the plurality of needle-shaped electrodes is perpendicular to the flow direction, the surfaces on which the needle-shaped electrodes are provided on the base of the first electrode and the base of the second electrode face each other, and one of the needle-shaped electrodes of the first electrode and one of the needle-shaped electrodes of the second electrode are alternately positioned in a plane perpendicular to the flow direction. The purification system according to claim 2.

5. The catalyst is provided on the surface of the electrode, The purification system according to claim 1.

6. The electrode has a conductive layer of metal and an insulating layer covering the conductive layer. The catalyst is provided on the surface of the insulating layer, The purification system according to claim 5.

7. The electrode is composed of multiple plate-shaped electrodes, The catalyst is provided on the opposing surfaces of the plurality of plate-shaped electrodes that face each other. The purification system according to claim 5.

8. The electrode comprises a first electrode having a plurality of plate-shaped electrodes and a base to which the sides of each plate-shaped electrode are connected, and a second electrode having a plurality of plate-shaped electrodes and a base to which the sides of each plate-shaped electrode are connected. Each of the plurality of plate-shaped electrodes of the first electrode and the second electrode is provided perpendicular to the base, The first electrode and the second electrode are arranged such that the surfaces on which the plate-shaped electrodes are provided on the bases of the first electrode and the second electrode face each other, the longitudinal direction of the bases is parallel to the gas flow direction, and one plate-shaped electrode of the first electrode and one plate-shaped electrode of the second electrode are positioned alternately. The purification system according to claim 6.

9. The electrode is provided such that its longitudinal direction is parallel to the flow direction of the gas through the pipe. The purification system according to claim 7 or 8.

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