Ultralow-concentration methane heat storage catalytic oxidation furnace

Abstract

The invention relates to the field of coal mine methane heat storage oxidation catalysis, and discloses an ultralow-concentration methane heat storage catalytic oxidation furnace which comprises a furnace body, the furnace body comprises a lower chamber body, a middle chamber body and an upper chamber body, the lower chamber body is provided with a gas inlet channel, a gas outlet channel and a middle channel, and the middle channel is communicated with the gas inlet channel and the gas outlet channel. A push-pull valve is arranged at the communication part, and the flow direction of the methane gas in the whole furnace body is controlled by controlling the opening and closing of the push-pull valve; the middle channel is composed of a plurality of subareas which are separated from one another, each subarea is connected with the middle chamber body, the middle chamber body is composed of a plurality of heat storage catalysis chambers, and ceramic honeycomb heat storage bodies and methane catalysts are placed in the heat storage catalysis chambers; the upper chamber body is a communicated combustion chamber, and a large amount of heat generated by combustion of ultralow-concentration methane in the combustion chamber is discharged from a high-temperature heat taking port for power generation or heat supply. The invention provides a stable, safe and efficient heat storage catalytic oxidation furnace for the utilization of ultralow-concentration methane, and has very important significance for carbon emission reduction.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of coal mine methane heat accumulation oxidation, in particular to a super-low concentration methane heat accumulation catalytic oxidation furnace. BACKGROUND

[0002] Coalbed gas is a gas resource associated with coal, which refers to hydrocarbon gas stored in coal seams, mainly composed of methane, and belongs to unconventional natural gas, commonly known as "methane". According to the different concentrations of methane, coal mine methane can be divided into high concentration methane and low concentration methane (including super-low concentration methane). High concentration methane generally refers to methane with a methane concentration of more than 30%, which can be directly mined through surface drilling and can be used as civil fuel, chemical raw material, etc., with simple technology and fast utilization. Low concentration methane generally refers to methane with a methane concentration of less than 30%, which is mainly extracted through the coal mine underground drainage system, so it is also called coal mine drainage methane. Low concentration methane with a methane concentration of 8%-30% can be used for internal combustion engine power generation, and the utilization progress is also relatively fast. Low concentration methane with a methane concentration of less than 8% is also called super-low concentration methane, which cannot be directly used for power generation due to its low concentration, and its total amount is huge, accounting for more than 80% of coal mine methane in China.

[0003] Methane is the second largest greenhouse gas in the world, with a global warming potential of 28 times that of carbon dioxide in a century, and a global warming contribution rate of 25%. Direct discharge of super-low concentration methane not only causes serious greenhouse gas emissions, but also leads to waste of energy resources. In order to improve the enthusiasm of super-low concentration methane utilization and respond to the national "double carbon" strategy, the Ministry of Ecology and Environment issued the "Methodology for Voluntary Greenhouse Gas Reduction Projects Methane Volume Concentration Less Than 8% Coal Mine Low Concentration Methane and Wind Drainage Methane Utilization" in January 2025, which not only provides policy basis and technical specifications for the super-low concentration methane utilization industry, but also provides an industrial development path.

[0004] Super-low concentration methane is discharged into the atmosphere during the ventilation process of coal mines, which will produce significant greenhouse effect. According to statistics, the methane discharged into the atmosphere by coal mine ventilation in China is equivalent to the annual gas transmission of West-East Gas Transmission, and the greenhouse effect is equivalent to 200 million tons of carbon dioxide equivalent. Therefore, it is of great significance to make full use of super-low concentration methane.

[0005] However, due to the characteristics of super-low concentration, large fluctuation range, and easy explosion when encountering open flame of methane in coal mines, how to deal with super-low concentration methane in coal mines is a great challenge. SUMMARY

[0006] The purpose of the present application is to provide an ultra-low concentration methane regenerative catalytic oxidation furnace to solve the problems of large fluctuation and difficult utilization of existing ultra-low concentration methane, easy explosion in high-temperature oxidation process, and inability to guarantee safety, and to improve the safety and stability of the ultra-low concentration methane treatment process.

[0007] To achieve the above-mentioned purpose, the present application provides an ultra-low concentration methane regenerative catalytic oxidation furnace, comprising a furnace body, the furnace body comprising a lower chamber body, a middle chamber body and an upper chamber body stacked in turn along the height direction; The lower chamber body comprises an inlet channel, an intermediate channel and an outlet channel arranged in turn along the width direction; the intermediate channel comprises a plurality of independent partitions distributed along the length direction, an inlet push-pull valve is arranged between each partition and the inlet channel for guiding the ultra-low concentration methane into the partition; an outlet push-pull valve is arranged between each partition and the outlet channel for discharging the catalytically oxidized reaction gas; wherein the intermediate channel is divided into at least a first partition unit and a second partition unit, the first partition unit and the second partition unit respectively comprising different at least one partition; The middle chamber body comprises a plurality of regenerative chambers distributed along the length direction, each regenerative chamber is correspondingly and communicatively arranged with the partition, and the regenerative chamber is provided with a ceramic regenerative body and a catalyst; wherein the middle chamber body is divided into at least a first regenerative chamber unit and a second regenerative chamber unit, the first regenerative chamber unit and the second regenerative chamber unit respectively comprising different at least one regenerative chamber; The upper chamber body is a combustion chamber for oxidizing the ultra-low concentration methane; Wherein, the ultra-low concentration methane is periodically introduced into the furnace body in batches for reaction, after the ultra-low concentration methane of the current batch is introduced into the first partition unit, the flue gas generated after heating by the first regenerative chamber unit and oxidation reaction by the combustion chamber is discharged in turn through the second regenerative chamber unit and the second partition unit, and the heat energy generated by the reaction is stored in the second regenerative chamber unit; After the ultra-low concentration methane of the next batch is introduced into the second partition unit, the flue gas generated after heating by the second regenerative chamber unit and oxidation reaction by the combustion chamber is discharged in turn through the first regenerative chamber unit and the first partition unit, and the heat energy generated by the reaction is stored in the first regenerative chamber unit.

[0008] Optionally, in combination with any of the above aspects, in another implementation manner of the present application, the lower chamber body is an overall skid-mounted structure, the intermediate channel comprises four independent partitions distributed along the length direction, and the middle chamber body comprises four regenerative chambers distributed along the length direction.

[0009] Optionally, in combination with any of the above aspects, in another implementation form of the aspect, the intermediate channel is provided with a high-strength heat storage body support frame in each of the sub-zones, and a cross-sectional shape of the intermediate channel in the width direction is Y-shaped.

[0010] Optionally, in combination with any of the above aspects, in another implementation form of the aspect, the inner wall of the heat storage chamber is provided with high-temperature-resistant ceramic aluminum silicate cotton with a temperature resistance ≥ 1200℃, and the thickness of the ceramic aluminum silicate cotton is 100-500 mm.

[0011] Optionally, in combination with any of the above aspects, in another implementation form of the aspect, the ceramic heat storage body and the catalyst are in a multi-layer composite stacking structure, and the multi-layer composite stacking structure is provided with a grid support net and a rhombic air uniformization net at the bottom.

[0012] Optionally, in combination with any of the above aspects, in another implementation form of the aspect, the multi-layer composite stacking structure comprises five layers of honeycomb ceramic heat storage body layers and one layer of catalyst layer.

[0013] Optionally, in combination with any of the above aspects, in another implementation form of the aspect, the multi-layer composite stacking structure comprises, in sequence along the air inlet direction, three layers of honeycomb ceramic heat storage body layers, a catalyst layer, and two layers of honeycomb ceramic heat storage body layers, and the length, width and height of each of the honeycomb ceramic heat storage body layers are 150mm×150mm×300mm, and the length, width and height of the catalyst layer are 150mm×150mm×50mm.

[0014] Optionally, in combination with any of the above aspects, in another implementation form of the aspect, the multi-layer composite stacking structure is further provided with a plurality of temperature sensors.

[0015] Optionally, in combination with any of the above aspects, in another implementation form of the aspect, the inner wall of the combustion chamber is provided with high-temperature-resistant ceramic aluminum silicate cotton with a temperature resistance ≥ 1200℃, and the thickness of the ceramic aluminum silicate cotton is 100-500 mm.

[0016] Optionally, in combination with any of the above aspects, in another implementation form of the aspect, the middle part of the combustion chamber is provided with a furnace head with a combustion system, a temperature sensor and a pressure sensor, the side of the upper chamber body is provided with a maintenance door, and the top of the upper chamber body is provided with a high-temperature heat extraction port and a blast vent.

[0017] Optionally, in combination with any of the above aspects, in another implementation form of the aspect, the air inlet push-pull valve or the air outlet push-pull valve comprises, in sequence, an air cylinder, a shaft coupling, a bearing adjuster, a valve plate, a valve seat and a support bearing, and the bearing adjuster is used to adjust the position of the push-pull valve plate so that the valve plate is tightly attached to the valve seat.

[0018] Working principle: the heat storage layer in the middle chamber body stores the heat released by the high-temperature oxidized methane gas, when the heat storage layer stores the heat to the limit, the methane gas inlet and outlet flow direction is switched, at this time, the heat storage layer stores the heat to heat the entering methane gas, so that it gradually rises to the required temperature of oxidation, as long as the gas concentration reaches the ignition value, without consuming the heat provided by the external furnace, the energy and temperature stored in the heat storage chamber can make the methane gas oxidized through the tower. The heat storage bed layer works alternately (average period 60-120 seconds), to ensure continuous and stable operation.

[0019] Through the above technical scheme, the ultra-low concentration methane heat storage catalytic oxidation furnace provided by the application has the effect that, by combining the heat storage and catalysis technologies, the ultra-low concentration methane is converted into heat energy, and the continuous, stable and intrinsically safe operation is realized, the industry problem is solved, and great economic and environmental benefits are obtained. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the application or the prior art, the drawings needed in the embodiment or prior art description will be briefly introduced below, and obviously, the drawings in the following description are only some embodiments described in the application, and other drawings can be obtained by those skilled in the art without creative labor.

[0021] Figure 1 The axial view of the embodiment of the application; Figure 2 The front view of the embodiment of the application; Figure 3 The side view of the embodiment of the application; Figure 4 The top view of the lower chamber body of the embodiment of the application; Figure 5 The heat storage body support grid and rhombus net structure of the ultra-low concentration methane heat storage catalytic oxidation furnace in the embodiment of the application; Figure 6 The push-pull valve structure of the ultra-low concentration methane heat storage catalytic oxidation furnace in the embodiment of the application; Figure 7 The methane conversion rate analyzed in embodiment 1 according to the application.

[0022] Explanation of reference signs: 100 - lower chamber body, 110 - inlet channel, 120 - intermediate channel, 131 - first inlet push-pull valve, 132 - first outlet push-pull valve, 133 - second inlet push-pull valve, 134 - second outlet push-pull valve, 135 - third inlet push-pull valve, 136 - third outlet push-pull valve, 137 - fourth inlet push-pull valve, 138 - fourth outlet push-pull valve, 1301 - push-pull valve cylinder, 1302 - push-pull valve coupling, 1303 - push-pull valve bearing adjuster, 1304 - push-pull valve plate, 1305 - push-pull valve seat, 1306 - push-pull valve support bearing, 140 - purge pipe set, 150 - lower chamber body intermediate channel, 151 - first intermediate channel section, 152 - second intermediate channel section, 153 - third intermediate channel section, 154 - fourth intermediate channel section, 160 - heat storage body support frame, 200 - middle chamber body, 201 - heat storage body support assembly, 2011 - rhombic air distribution grid, 2012 - grid support net, 202 - first honeycomb ceramic heat storage body layer, 203 - second honeycomb ceramic heat storage body layer, 204 - third honeycomb ceramic heat storage body layer, 205 - catalyst layer, 206 - fourth honeycomb ceramic heat storage body layer, 207 - fifth honeycomb ceramic heat storage body layer, 251 - first heat storage chamber, 252 - second heat storage chamber, 253 - third heat storage chamber, 254 - fourth heat storage chamber, 300 - upper chamber body, 301 - upper chamber body shell, 302 - combustion chamber, 310 - upper chamber body maintenance door, 320 - burner head, 330 - high-temperature heat extraction port, 340 - explosion vent, 350 - inner heat insulation ceramic aluminum silicate wool. DETAILED DESCRIPTION

[0023] The exemplary embodiments will be described in detail herein with reference to the attached drawings. The description of the exemplary embodiments is intended to apply to all alternative embodiments, as would be understood by one skilled in the art. The following description is presented for the purpose of clarity and explanation only. Therefore, the description is not intended to limit the scope of the exemplary embodiments as set forth in the claims.

[0024] It should be noted that, in this article, the term "comprise", "include" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not clearly listed, or also includes elements inherent to such process, method, article or device. In the absence of more restrictions, the elements limited by the sentence "comprise one..." do not exclude the presence of other identical elements in the process, method, article or device comprising the element. It should be further understood that, as used in this article, the singular forms "one", "an" and "the" are intended to also include plural forms, unless there is an opposite indication in the context. Furthermore, the terms "or", "and / or", "including at least one of the following" etc. used in this article can be interpreted as inclusive, or mean any one or any combination. Only when the combination of elements, functions, steps or operations is inherently mutually exclusive in some way, will the exception to this definition occur.

[0025] It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the scope of rights of the present application.

[0026] like Figures 1-7 As shown, as an example, a four-tower (two-inlet, two-outlet) ultra-low-concentration methane thermal storage catalytic oxidation furnace is shown. It should be noted that although a four-tower structure is shown, this application does not limit the number of towers. Those skilled in the art will appreciate that, based on this example, two or more tower structures can be provided based on the actual methane exhaust gas emissions.

[0027] like Figure 1 As shown, the furnace body comprises a lower chamber 100, a middle chamber 200, and an upper chamber 300 stacked in sequence along the height direction. Lower chamber 100 is used for air intake and exhaust, middle chamber 200 is used for heating the intake air and performing catalytic oxidation, and upper chamber 300 is an integrally connected combustion chamber 302 for oxidizing ultra-low concentration methane. Each chamber is described in detail below.

[0028] like Figures 1-4 As shown, the lower chamber 100 includes an inlet channel 110, an intermediate channel 150, and an outlet channel 120, arranged sequentially along the width. The intermediate channel 150 includes four independent sections 151-154 distributed along the length. An inlet push-pull valve is installed between each section and the inlet channel 110 to introduce ultra-low-concentration methane gas into the corresponding section. An outlet push-pull valve is also installed between each section and the outlet channel 120 to discharge the reaction gas after catalytic oxidation.

[0029] like Figure 4As shown, four air inlet push-pull valves 131, 133, 135 and 137 are arranged in the air inlet channel 110, and four air outlet push-pull valves 132, 134, 136 and 138 are arranged in the air outlet channel 120 correspondingly. Among them, the air inlet push-pull valve 131 and the air outlet push-pull valve 132 are respectively used for air inlet and air outlet of the first intermediate channel partition 151, the air inlet push-pull valve 133 and the air outlet push-pull valve 134 are respectively used for air inlet and air outlet of the second intermediate channel partition 152, the air inlet push-pull valve 135 and the air outlet push-pull valve 136 are respectively used for air inlet and air outlet of the third intermediate channel partition 153, and the air inlet push-pull valve 137 and the air outlet push-pull valve 138 are respectively used for air inlet and air outlet of the fourth intermediate channel partition 154.

[0030] Please refer to Figures 1-3 The middle chamber body 200 includes four heat storage chambers 251-254 distributed along the length direction, each of which is arranged in one-to-one correspondence with and in communication with each of the independent partitions 151-154 of the lower chamber body 100.

[0031] Each heat storage chamber is provided with a multi-layer composite stacking structure composed of ceramic heat storage bodies and catalysts. As shown in Figure 5 The bottom of the multi-layer composite stacking structure is provided with a heat storage body support assembly 201, which includes a rhombic air equalization net 2011 and a grid support net 2012, for supporting the multi-layer composite stacking structure and uniformly guiding the air into the multi-layer composite stacking structure. Preferably, the grid support net 2012 and the rhombic air equalization net are made of temperature-resistant 304 material. Preferably, the size of the grid support net 2012 is larger than that of the multi-layer composite stacking structure, and is provided with a peripheral compensator to compensate for expansion and contraction caused by high and low temperature switching.

[0032] Optionally, the multi-layer composite stacking structure is arranged in the order of a first honeycomb ceramic heat storage body layer 202, a second honeycomb ceramic heat storage body layer 203, a third honeycomb ceramic heat storage body layer 204, a catalyst layer 205, a fourth honeycomb ceramic heat storage body layer 206 and a fifth honeycomb ceramic heat storage body layer 207 along the air inlet direction. Among them, the length, width and height of each honeycomb ceramic heat storage body layer are 150mm x 150mm x 300mm, and the length, width and height of the catalyst layer are 150mm x 150mm x 50mm. Each layer of heat storage body and the catalyst layer are closely placed to ensure no leakage.

[0033] After the ultra-low concentration methane is heated to the catalytic activation temperature by the first three layers of honeycomb ceramic heat storage body layers, it is subjected to catalytic oxidation reaction in the fourth layer of catalyst, about 30%-50% of the methane gas is catalytically oxidized, so as to ensure that the concentration of the methane gas entering the upper chamber body 300 is further reduced to below the lower explosive limit, and the safe operation is achieved in essence.

[0034] Further refer to Figures 1-3The upper chamber body 300 is a whole communication combustion chamber 302 composed of an upper chamber body shell 301, used for oxidizing the ultra-low concentration methane. A plurality of evenly distributed furnace heads 320 (two are shown) with combustion systems are arranged in the middle of the combustion chamber 302, so that the furnace body can be preheated faster and more uniformly in the preheating stage. The whole furnace body is preheated by the heat supply of the furnace head before the furnace body is operated, and the preheating is completed when the hearth reaches 950 DEG C. The methane gas reaches a certain residence time in the hearth, so that the methane is completely oxidized to carbon dioxide and water, and a large amount of heat is released, which is discharged through the high-temperature heat extraction port 330 for power generation or heat supply. The top of the upper chamber body 300 is provided with an explosion vent 340, which further improves the safety of the equipment. The side of the upper chamber body 300 is provided with a maintenance door 310, which is convenient for repairing or replacing the heat storage body and catalyst in the heat storage chamber.

[0035] Optionally, the inner wall of the heat storage chamber and the inner wall of the combustion chamber 302 are provided with high-temperature resistant ceramic aluminum silicate cotton, and the temperature resistance is ≥1200 DEG C. The thickness of the ceramic aluminum silicate cotton is 100-500 mm, preferably 250 mm, 300 mm or 350 mm. When the furnace body is normally operated, the furnace wall temperature is not higher than 40 DEG C of the ambient temperature, so as to ensure that the heat loss of the furnace body is minimized and a large amount of energy is saved.

[0036] Before the furnace body is normally operated, the plurality of independent partitions of the intermediate channel 200 are at least divided into a first partition unit and a second partition unit, and the first partition unit and the second partition unit respectively include different at least one partition. Correspondingly, the plurality of heat storage chambers of the middle chamber body 200 are also at least divided into a first heat storage chamber unit and a second heat storage chamber unit, and the first heat storage chamber unit and the second heat storage chamber unit respectively include different at least one heat storage chamber. Thus, the two partition units can alternately perform gas inlet and gas outlet, and the two heat storage chamber units can alternately perform preheating and heat storage, and the heat storage bed layers alternately work, with an average period of 60-120 seconds, so as to ensure that the furnace body can be continuously, efficiently and stably operated.

[0037] Specifically, the ultra-low concentration methane is periodically introduced into the furnace body in batches for reaction. After the current batch of ultra-low concentration methane is introduced into the first partition unit, the flue gas generated after the heating of the first heat storage chamber unit and the oxidation reaction of the combustion chamber is discharged in turn through the second heat storage chamber unit and the second partition unit, and at the same time, the heat energy generated by the reaction is stored in the second heat storage chamber unit.

[0038] Next, after the next batch of ultra-low concentration methane is introduced into the second partition unit, the flue gas generated after the heating of the second heat storage chamber unit and the oxidation reaction of the combustion chamber is discharged in turn through the first heat storage chamber unit and the first partition unit, and at the same time, the heat energy generated by the reaction is stored in the first heat storage chamber unit.

[0039] The following will be described in combination with the drawingsFigures 1-4 When the ultra-low concentration methane gas enters from the inlet channel 110, the first inlet push-pull valve 131 of the first intermediate channel section 151 and the second inlet push-pull valve 133 of the second intermediate channel section 152 are opened, and the third inlet push-pull valve 135 of the third intermediate channel section 153 and the fourth inlet push-pull valve 137 of the fourth intermediate channel section 154 are closed; at the same time, in the corresponding outlet channel 120, the first outlet push-pull valve 132 of the first intermediate channel section 151 and the second outlet push-pull valve 134 of the second intermediate channel section 152 are closed, and the third outlet push-pull valve 136 of the third intermediate channel section 153 and the fourth outlet push-pull valve 138 of the fourth intermediate channel section 154 are opened. Thus, the first intermediate channel section 151 and the second intermediate channel section 152 constitute a first section unit, and the third intermediate channel section 153 and the fourth intermediate channel section 154 constitute a second section unit; correspondingly, the first regenerator 151 and the second regenerator 152 constitute a first regenerator unit, and the third regenerator 153 and the fourth regenerator 154 constitute a second regenerator unit. At this time, the methane gas enters the first regenerator unit composed of the first regenerator 151 and the second regenerator 152 from the first section unit composed of the first intermediate channel section 151 and the second intermediate channel section 152, and is gradually heated by the lower three honeycomb ceramic regenerator layers 202-204, when the methane gas reaches the catalytic layer 205, part of the methane gas is catalytically oxidized, so that the concentration of methane gas is reduced, and then enters the last two honeycomb ceramic regenerator layers 206 and 207 to continue to heat to 950°C. Subsequently, the high-temperature methane gas is oxidized to carbon dioxide and water in the combustion chamber 302 and releases a large amount of heat, part of the heat energy is discharged from the high-temperature heat extraction port 330 at the top of the upper chamber body 300 with the flue gas, which is used for power generation or heating, and the other part of the heat energy enters the second regenerator unit composed of the third regenerator 153 and the fourth regenerator 154 with the flue gas, and stores heat in the regenerator.

[0040] When the heat storage of the heat storage body is full, the first intake push-pull valve 131 of the first intermediate passage section 151 and the second intake push-pull valve 133 of the second intermediate passage section 152 are closed, and the third intake push-pull valve 135 of the third intermediate passage section 153 and the fourth intake push-pull valve 137 of the fourth intermediate passage section 154 are opened. At the same time, in the corresponding exhaust passage 120, the first exhaust push-pull valve 132 of the first intermediate passage section 151 and the second exhaust push-pull valve 134 of the second intermediate passage section 152 are opened, and the third exhaust push-pull valve 136 of the third intermediate passage section 153 and the fourth exhaust push-pull valve 138 of the fourth intermediate passage section 154 are closed. The methane intake flow direction is changed to be introduced into the furnace body from the second sub-unit composed of the third intermediate passage section 153 and the fourth intermediate passage section 154. At this time, the methane gas will enter the combustion chamber 302 from the third heat storage chamber 153 and the fourth heat storage chamber 154, and be discharged after being fully oxidized and combusted. Such alternating and reciprocating cycle operation realizes stable operation, and the alternating average period is 60-120 seconds.

[0041] As can be seen, the heat storage body in the middle chamber body stores the heat released by the methane gas after high-temperature oxidation. When the heat storage of the heat storage layer reaches the limit, the methane intake and exhaust flow directions are switched. At this time, the heat storage layer stores heat to heat the incoming methane gas, which gradually rises to the required temperature for oxidation. As long as the gas concentration reaches the self-ignition value, the energy and temperature stored in the heat storage chamber can make the methane gas in the furnace oxidize without consuming the heat provided by the furnace head. The super-low concentration methane heat storage catalytic oxidation furnace provided in the embodiment realizes efficient methane oxidation by alternating use of heat storage and catalysis, converts super-low concentration methane into heat energy, and can continuously, stably and intrinsically safely operate.

[0042] As shown in Figure 6 The intake push-pull valves 131, 133, 135 and 137 and the exhaust push-pull valves 132, 134, 136 and 138 each include a cylinder 1301, a shaft coupling 1302, a bearing adjuster 1303, a valve plate 1304, a valve seat 1305 and a support bearing 1306 connected in sequence. The bearing adjuster 1303 can adjust the center position of the valve plate 1304 up, down, left and right, so that the valve plate 1304 and the valve seat 1305 are completely closed and fit, realizing zero leakage. Preferably, the valve plate 1304 is made of 304 material with a wall thickness of 3 mm, which can produce recoverable deformation under thrust while ensuring strength, so that the valve plate 1304 and the valve seat 1305 fit more reliably.

[0043] Alternatively, as shown in Figures 1-2As shown, a purge pipe group 140 is also arranged in each partition in the lower chamber body 100, for completely discharging the reacted gas from the furnace body, so that the next batch of methane gas can be efficiently and stably treated. Embodiment

[0044] This embodiment is equipped with a 5000Nm 3 / h ultra-low concentration methane regenerative catalytic oxidation furnace for a certain research institute, which is designed in a double-tower structure. Five layers of regenerative bricks are arranged in a single tower body, and one layer of catalyst is arranged on the upper part of the third layer of regenerative bricks. During the operation of the furnace body, one gas inlet and one gas outlet are designed, and four push-pull valves, one group of gas inlets and one group of gas outlets are arranged in the lower chamber body, which are operated alternately, and the valve switching time is 90S. A heat extraction port is reserved at the top. The methane inlet concentration is set to 6000ppm, and the methane inlet is uniformly mixed with air in a static mixer. The inlet concentration is monitored and fed back in real time by an online analysis instrument. The catalyst design space velocity is 10000h -1 , the catalyst loading of a single furnace body is 0.5m 3 , and the total filling amount is 1m 3 . During actual operation, the regenerative bricks and catalysts in the first tower body are preheated to the reaction temperature by a 300kW electric heater. After preheating, methane-air mixture with a concentration of 6000ppm is introduced. The mixed gas is first heated by the regenerative bricks and then catalytically oxidized in the catalyst layer to release heat. The reacted hot flue gas heats the regenerative bricks and catalysts in the second tower body. After 90S, the methane-air mixture with a concentration of 6000ppm enters the heated regenerative bricks and catalysts through valve switching to perform catalytic oxidation reaction. The reacted hot flue gas heats the regenerative bricks and catalysts in the first tower body, and the above process is repeated subsequently. The reacted flue gas is discharged through a pipeline, and an online analysis instrument is arranged at the outlet to monitor the outlet methane concentration in real time.

[0045] Reference Figure 7 Under different temperature conditions, the ultra-low concentration methane regenerative catalytic oxidation furnace shows excellent catalytic performance: the methane conversion efficiency is more than 99% at 380℃, more than 99% at 360℃, more than 97.53% at 340℃, 35% at 330℃, and 17.96% at 320℃.

[0046] It should be noted that the above detailed description is exemplary and is intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used in the present application have the same meaning as that understood by ordinary skilled persons in the technical field to which the present application belongs.

[0047] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments in accordance with the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, steps, operations, elements, components, and / or groups thereof, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof.

[0048] It should be noted that the terms "first", "second", and the like, herein do not necessarily have an ordinal meaning. Rather, these terms are used herein, inter alia, to distinguish a certain feature from another feature. It should be understood that the use of these terms is not intended to limit the scope of the embodiments described herein to only those embodiments which can be claimed using these terms. Rather, the scope of those embodiments is limited only by the claims.

[0049] Furthermore, the term "comprising" and "including" and their variants are intended to cover both the case where only the stated features are present and the case where additional features are also present. For example, a process, method, system, product, or apparatus that comprises or includes only the steps of those explicitly disclosed is still within the scope of the example embodiments.

[0050] For the purposes of the description hereinafter, the terms "upper", "lower", "right", "left", "rear", "front", "vertical", "horizontal", and derivatives thereof shall relate to the application as oriented in the drawings. However, it is to be understood that the application can assume various alternative orientations and, accordingly, such terms are not to be taken as limitations of the present application or any embodiments thereof described herein or is to be understood assuming each alternative orientation. Accordingly, the attached drawings are not necessarily drawn to scale.

[0051] In the detailed description herein, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments can be used, and other changes can be made, without departing from the spirit or scope of the subject matter presented herein.

[0052] The above merely describes the preferred embodiments of the present application, and is not used to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An ultra-low concentration methane thermal storage catalytic oxidation furnace, characterized in that: The furnace body comprises a lower chamber body, a middle chamber body and an upper chamber body stacked in sequence along the height direction; The lower chamber body includes an air inlet channel, an intermediate channel, and an air outlet channel arranged in sequence along the width direction; the intermediate channel includes a plurality of independent partitions distributed along the length direction, an air inlet push-pull valve is provided between each partition and the air inlet channel for introducing the ultra-low concentration methane into the partition; an air outlet push-pull valve is provided between each partition and the air outlet channel for discharging the reaction gas after catalytic oxidation; wherein the intermediate channel is divided into at least a first partition unit and a second partition unit, and the first partition unit and the second partition unit respectively include at least one different partition; The middle chamber body includes a plurality of heat storage chambers distributed along the length direction, each heat storage chamber corresponding to and communicating with a partition, and a ceramic heat storage body and a catalyst are arranged in the heat storage chamber; wherein the middle chamber body is divided into at least a first heat storage chamber unit and a second heat storage chamber unit, and the first heat storage chamber unit and the second heat storage chamber unit respectively include at least one different heat storage chamber; The upper chamber body is an integrally connected combustion chamber, which is used to carry out an oxidation reaction on the ultra-low concentration methane; The ultra-low concentration methane is periodically introduced into the furnace body in batches for reaction. After the current batch of ultra-low concentration methane is introduced into the first partition unit, it is heated by the first regenerator unit and oxidized by the combustion chamber. The generated flue gas is discharged through the second regenerator unit and the second partition unit in sequence, and the heat energy generated by the reaction is stored in the second regenerator unit. After the next batch of ultra-low concentration methane is introduced into the second partition unit, it is heated by the second regenerator unit and oxidized by the combustion chamber. The generated flue gas is discharged through the first regenerator unit and the first partition unit in sequence, and the heat energy generated by the reaction is stored in the first regenerator unit.

2. The ultra-low concentration methane thermal storage catalytic oxidation furnace according to claim 1, characterized in that: The lower chamber body is an integral skid-mounted structure, the middle channel includes four independent partitions distributed along the length direction, and the middle chamber body includes four heat storage chambers distributed along the length direction.

3. The ultra-low concentration methane thermal storage catalytic oxidation furnace according to claim 1 or 2, characterized in that: A high-strength heat storage body support frame is provided in each partition of the middle channel, and the cross-sectional shape of the middle channel in the width direction is Y-shaped.

4. The ultra-low concentration methane thermal storage catalytic oxidation furnace according to claim 1, characterized in that: The inner wall of the heat storage chamber is provided with high-temperature resistant ceramic aluminum silicate wool, which has a temperature resistance of ≥1200°C and a thickness of 100-500 mm.

5. The ultra-low concentration methane thermal storage catalytic oxidation furnace according to claim 1, characterized in that: The ceramic heat storage body and the catalyst are a multi-layer composite stacking structure, and a grid support net and a diamond-shaped air distribution net are provided at the bottom of the multi-layer composite stacking structure.

6. The ultra-low concentration methane thermal storage catalytic oxidation furnace according to claim 5, characterized in that: The multi-layer composite stacking structure includes five honeycomb ceramic heat storage layers and one catalyst layer.

7. The ultra-low concentration methane thermal storage catalytic oxidation furnace according to claim 6, characterized in that: The multi-layer composite stacking structure consists of three layers of honeycomb ceramic heat storage layer, a catalyst layer and two layers of honeycomb ceramic heat storage layer in sequence along the air inlet direction. The length, width and height dimensions of each honeycomb ceramic heat storage layer are 150mm×150mm×300mm, and the length, width and height dimensions of the catalyst layer are 150mm×150mm×50mm.

8. The ultra-low concentration methane thermal storage catalytic oxidation furnace according to any one of claims 5 to 7, characterized in that Several temperature sensors are also arranged in the multi-layer composite stacking structure.

9. The ultra-low concentration methane thermal storage catalytic oxidation furnace according to claim 1, characterized in that: The inner wall of the combustion chamber is provided with high-temperature resistant ceramic aluminum silicate wool, which has a temperature resistance of ≥1200°C and a thickness of 100-500 mm.

10. The ultra-low concentration methane thermal storage catalytic oxidation furnace according to claim 1 or 9, characterized in that: A burner with a combustion system, a temperature sensor and a pressure sensor are arranged in the middle of the combustion chamber, a maintenance door is arranged on the side of the upper chamber body, and a high-temperature heat outlet and an explosion vent are arranged on the top of the upper chamber body.

11. The ultra-low concentration methane thermal storage catalytic oxidation furnace according to claim 1, characterized in that: The air inlet push-pull valve or the air outlet push-pull valve includes a cylinder, a coupling, a bearing adjuster, a valve plate, a valve seat and a support bearing connected in sequence. The bearing adjuster is used to adjust the position of the push-pull valve plate so that the valve plate and the valve seat are tightly fitted.

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