Flue gas treatment system and graphitization furnace

Abstract

The utility model relates to a flue gas treatment system and a graphitization furnace. The flue gas treatment system comprises a cooling tower which is communicated with a flue gas outlet of the graphitization furnace and is used for cooling initial flue gas; the incinerator communicates with a flue gas outlet of the cooling tower and is used for combusting flue gas discharged by the cooling tower; and the secondary treatment equipment communicates with a flue gas outlet of the incinerator and is used for recycling heat of the first flue gas discharged by the incinerator and purifying the first flue gas. According to the flue gas treatment system, through cooperative arrangement of the cooling tower, the incinerator and the secondary treatment equipment, the probability that functional parts in the incinerator and the secondary treatment equipment are damaged due to the too high temperature of flue gas can be reduced. And meanwhile, the difficulty of heat recovery and purification of the flue gas by secondary treatment equipment at the rear end can be reduced. Therefore, the purification effect of the secondary treatment equipment at the rear end on the flue gas is improved, the flue gas exhausted from the tail end meets the emission standard, and the pollution to the environment is reduced.

Description

Technical Field

[0001] This application relates to the field of flue gas treatment technology for graphitization furnaces, and in particular to a flue gas treatment system and a graphitization furnace. Background Technology

[0002] When producing graphite materials using a graphitization furnace, carbonaceous materials need to undergo a high-temperature reaction within the furnace's reaction chamber to be graphitized, thereby transforming them into more stable graphite materials. The graphitization process within the reaction chamber generates a large amount of high-temperature flue gas (volatiles).

[0003] In related technologies, the treatment method for high-temperature flue gas involves connecting an external flue gas purification device to the graphitization furnace. This device directly draws out the high-temperature flue gas from the furnace, purifies it, and then discharges it directly to the outside. However, in this method, the functional components of the flue gas purification device are easily damaged by the excessively high temperature of the flue gas. Furthermore, the purification effect on high-temperature flue gas is often poor, making it difficult to meet emission standards and potentially causing significant environmental pollution. Utility Model Content

[0004] This application aims to address the problems of current methods for treating high-temperature flue gas generated by graphitization furnaces, such as the easy damage to the functional components of the flue gas purification device due to the excessively high temperature of the flue gas, and the poor purification effect on high-temperature flue gas. Therefore, this application provides a flue gas treatment system and a graphitization furnace.

[0005] In a first aspect, this application provides a flue gas treatment system for treating initial flue gas discharged from a graphitization furnace, the flue gas treatment system comprising:

[0006] A cooling tower is connected to the flue gas outlet of the graphitization furnace and is used to cool the initial flue gas.

[0007] An incinerator, connected to the flue gas outlet of the cooling tower, is used to burn the flue gas discharged from the cooling tower;

[0008] A secondary treatment device is connected to the flue gas outlet of the incinerator and is used to recover the heat of the first flue gas discharged from the incinerator and purify the first flue gas.

[0009] The flue gas treatment system according to the first aspect of this application has at least the following beneficial effects:

[0010] The flue gas treatment system of this application, through the coordinated arrangement of a cooling tower, an incinerator, and secondary treatment equipment, pre-cools and removes heavy components from the initial flue gas discharged from the graphitization furnace. This lowers the temperature of the initial flue gas to a level that the functional components in the downstream incinerator and secondary treatment equipment can withstand, thereby reducing the probability of damage to these components due to excessively high flue gas temperatures. Simultaneously, by pre-removing heavy components from the initial flue gas through the cooling tower, the difficulty of heat recovery and purification of the flue gas in the downstream secondary treatment equipment is reduced. Thus, the purification effect of the downstream secondary treatment equipment on the flue gas is improved, ensuring that the flue gas discharged at the end meets emission standards and reducing environmental pollution.

[0011] In some embodiments, the cooling tower includes a tower body and a spraying mechanism, the spraying mechanism being disposed at the top or bottom of the tower body for spraying a first cooling medium into the tower body.

[0012] This design allows the primary cooling medium inside the tower to exchange heat with the initial flue gas entering the tower, reducing the temperature of the initial flue gas and decreasing the probability of damage to functional components in the downstream incinerator and secondary treatment equipment due to excessively high flue gas temperatures. Simultaneously, the primary cooling medium adsorbs and removes heavy components from the initial flue gas, reducing the difficulty of heat recovery and purification in the downstream secondary treatment equipment, improving its purification efficiency, and ensuring that the discharged flue gas meets emission standards, thus reducing environmental pollution.

[0013] In some embodiments, cooling pipes are arranged on the peripheral wall of the tower body, and a second cooling medium is circulated within the cooling pipes.

[0014] With this configuration, the initial flue gas comes into contact with the cooling pipes on the tower's perimeter wall and exchanges heat with the second cooling medium within the pipes. This, combined with the cooling effect of the first cooling medium, accelerates the cooling efficiency of the initial flue gas. Furthermore, the water film formed on the pipe walls can also adsorb heavy components in the initial flue gas, further enhancing the removal efficiency of these heavy components, in conjunction with the adsorption effect of the first cooling medium.

[0015] In some embodiments, the cooling tower further includes a solid-liquid separation mechanism disposed at the bottom of the tower body, the solid-liquid separation mechanism being used to receive a solid-liquid mixture flowing down from the upper part of the tower body and to separate the solid-liquid mixture.

[0016] With this configuration, the first cooling medium inside the tower absorbs the heat from the initial flue gas inside the tower and adsorbs the heavy components in the initial flue gas, becoming a solid-liquid mixture composed of the liquid first cooling medium and the solid heavy components. The solid-liquid mixture falls to the bottom of the tower by gravity and is received by the solid-liquid separation mechanism at the bottom of the tower. The solid-liquid separation mechanism separates the liquid first cooling medium and the solid heavy components in the solid-liquid mixture, thereby recovering the first cooling medium and the solid heavy components respectively.

[0017] In some embodiments, the secondary processing device includes:

[0018] A waste heat recovery device is connected to the flue gas outlet of the incinerator and is used to exchange heat with the first flue gas discharged from the incinerator in order to recover the heat of the first flue gas.

[0019] A dust removal device is connected to the flue gas outlet of the waste heat recovery device and is used to remove dust from the second flue gas discharged from the waste heat recovery device.

[0020] A desulfurization device is connected to the flue gas outlet of the dust removal device and is used to desulfurize and denitrify the third flue gas discharged from the dust removal device.

[0021] This configuration allows the incinerator to burn the combustibles in the initial flue gas discharged from the graphitization furnace, fully releasing the heat from the initial flue gas so that the downstream waste heat recovery device can improve the heat recovery rate. The waste heat recovery device recovers a large amount of heat from the first flue gas discharged from the incinerator, reducing direct heat loss, improving energy utilization, and reducing energy waste. The dust removal device removes dust and particulate matter from the second flue gas discharged from the waste heat recovery device, achieving filtration and purification of the second flue gas. The desulfurization device removes gaseous pollutants from the third flue gas discharged from the dust removal device, achieving filtration and purification of the third flue gas, ensuring that the final emission gas meets emission standards. In this way, a large amount of heat from the high-temperature flue gas discharged from the graphitization furnace is effectively recovered, improving energy utilization and reducing energy waste. Moreover, the high-temperature flue gas discharged from the graphitization furnace is transformed into clean, green flue gas that meets emission standards, reducing environmental pollution.

[0022] In some embodiments, the waste heat recovery device includes a waste heat boiler and a high-temperature economizer connected to the waste heat boiler. The waste heat boiler is used to exchange heat with the first flue gas, and the high-temperature economizer is used to exchange heat with the flue gas discharged from the waste heat boiler. The heat exchange pipeline of the high-temperature economizer is connected to the steam drum of the waste heat boiler, and the flue gas outlet of the high-temperature economizer is connected to the dust removal device.

[0023] This configuration allows the first flue gas to undergo heat exchange twice consecutively, enabling more effective recovery and utilization of the heat from the first flue gas discharged from the incinerator, thereby further improving energy efficiency.

[0024] In some embodiments, the waste heat recovery device further includes a low-temperature economizer, the flue gas inlet of which is connected to the flue gas outlet of the high-temperature economizer for heat exchange with the flue gas discharged from the high-temperature economizer, the heat exchange pipeline of the low-temperature economizer being connected to the steam drum of the waste heat boiler, and the flue gas outlet of the low-temperature economizer being connected to the dust removal device.

[0025] This configuration allows the first flue gas to undergo heat exchange three times consecutively, enabling more effective recovery and utilization of the heat from the first flue gas discharged from the incinerator, thereby further improving energy efficiency.

[0026] In some embodiments, the heat exchange pipelines of the low-temperature economizer, the heat exchange pipelines of the high-temperature economizer, and the steam drum of the waste heat boiler are connected in sequence; and / or,

[0027] The heat exchange pipelines of the high-temperature economizer, the heat exchange pipelines of the low-temperature economizer, and the steam drum of the waste heat boiler are connected in sequence.

[0028] This configuration effectively simplifies the piping arrangement between the heat exchanger of the low-temperature economizer, the heat exchanger of the high-temperature economizer, and the steam drum of the waste heat boiler, and also saves the water supply to the low-temperature economizer and the high-temperature economizer.

[0029] In some embodiments, the waste heat recovery device further includes a high-temperature air preheater, wherein the flue gas outlet of the high-temperature economizer, the flue gas inlet of the high-temperature air preheater, the flue gas outlet of the high-temperature air preheater, and the flue gas inlet of the low-temperature economizer are connected in sequence, and the air outlet of the high-temperature air preheater is connected to the flue gas inlet of the incinerator.

[0030] With this setup, the first flue gas discharged from the incinerator flows sequentially through the waste heat boiler, the high-temperature economizer, the high-temperature air preheater, and the low-temperature economizer. After four heat exchanges, it becomes a low-temperature third flue gas and is discharged from the low-temperature economizer into the dust removal device for dust removal. This efficiently recovers the heat from the first flue gas and significantly reduces the temperature of the flue gas entering the dust removal device.

[0031] Meanwhile, the high-temperature air preheater can also supply preheated air to the incinerator, which is conducive to strengthening the ignition and combustion process of the incinerator, so that the combustibles in the initial flue gas can be fully burned, improving the combustion efficiency of the incinerator, and correspondingly improving the heat release efficiency in the initial flue gas, which is beneficial to the downstream waste heat recovery device to improve the heat recovery rate.

[0032] In some embodiments, the waste heat recovery device further includes a low-temperature air preheater, which is located on the connecting pipeline between the low-temperature economizer and the dust removal device, and the air outlet of the low-temperature air preheater is also connected to the flue gas inlet of the incinerator.

[0033] With this setup, the first flue gas discharged from the incinerator flows sequentially through the waste heat boiler, high-temperature economizer, high-temperature air preheater, low-temperature economizer, and low-temperature air preheater. After five heat exchanges, it becomes low-temperature second flue gas and is discharged from the low-temperature economizer into the dust removal device for dust removal. This efficiently recovers the heat from the first flue gas and significantly reduces the temperature of the flue gas entering the dust removal device.

[0034] Meanwhile, the high-temperature air preheater and the low-temperature air preheater can also supply preheated air medium to the incinerator, which is conducive to strengthening the ignition and combustion process of the incinerator, so that the combustibles in the initial flue gas are fully burned, improving the combustion efficiency of the incinerator, and correspondingly improving the heat release efficiency in the initial flue gas, which is beneficial to improving the heat recovery rate of the downstream waste heat recovery device.

[0035] In some embodiments, the air outlet of the low-temperature air preheater, the air inlet of the high-temperature air preheater, the air outlet of the high-temperature air preheater, and the flue gas inlet of the incinerator are sequentially connected; and / or,

[0036] The air outlet of the high-temperature air preheater, the air inlet of the low-temperature air preheater, the air outlet of the low-temperature air preheater, and the flue gas inlet of the incinerator are connected in sequence.

[0037] This configuration effectively simplifies the piping arrangement between the low-temperature air preheater, the high-temperature air preheater, and the incinerator, and also saves the amount of air supplied to the low-temperature air preheater and the high-temperature air preheater.

[0038] In some embodiments, the secondary treatment equipment further includes a pressure relief mechanism, which is disposed on the connecting pipe between the flue gas outlet of the waste heat boiler and the flue gas inlet of the high-temperature economizer.

[0039] This setup improves the safety and operational stability of the waste heat recovery device.

[0040] In some embodiments, the incinerator is equipped with an igniter for igniting the incinerator when it is shut down.

[0041] This design allows the igniter to automatically ignite the fuel gas inside the incinerator, ensuring complete combustion of the combustibles and full release of heat from the flue gas. Simultaneously, it reduces the probability of fuel gas accumulating inside the incinerator and causing an explosion, thus improving the incinerator's safety and stability.

[0042] Secondly, this application provides a graphitization furnace, which includes the flue gas treatment system described above.

[0043] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0044] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0045] Figure 1 This is a schematic diagram of the graphitization furnace according to an embodiment of this application.

[0046] Figure 2 This is a schematic diagram of the flue gas treatment system according to an embodiment of this application.

[0047] Figure 3 This is another structural schematic diagram of the flue gas treatment system according to an embodiment of this application.

[0048] Explanation of reference numerals in the attached drawings: Graphitization furnace 10; Reaction chamber 11; Incinerator 20; Ignition device 21; Second induced draft fan 22; Waste heat recovery device 30; Waste heat boiler 31; Steam drum 311; High-temperature economizer 32; Low-temperature economizer 33; High-temperature air preheater 34; Low-temperature air preheater 35; Dust removal device 40; Desulfurization device 50; First induced draft fan 51; Chimney 52; Pressure relief mechanism 60; Cooling tower 70; Tower body 71; Spraying mechanism 72; Cooling pipe 73; Solid separation mechanism 74. Detailed Implementation

[0049] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0050] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0051] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0052] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0053] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0054] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0055] This application relates to a graphitization furnace, which can transform the disordered layer structure of carbon atoms into an ordered graphite crystal structure through heating, thereby achieving the graphitization treatment of non-graphitic carbon. Graphitization aims to improve the thermal and electrical conductivity of carbon materials, enhance their thermal shock resistance and chemical stability, impart lubricity and wear resistance, increase their purity, reduce their hardness, and make them easier to machine, among other things.

[0056] Currently, graphitization furnaces are mainly used for the sintering and graphitization of carbon materials, graphitization of polyimide films (PI films), graphitization of thermal conductive materials, sintering of carbon fiber ropes, graphitization of carbon fiber filaments, graphite purification, and high-temperature processing of other materials that can be graphitized in a carbon environment. In some specific applications, graphite materials processed in graphitization furnaces can be used to form negative electrode materials for batteries; for example, graphite is currently a major negative electrode material for lithium batteries.

[0057] In this application, a battery refers to a physical module comprising one or more battery cells to provide electrical energy. A battery generally includes a casing for encapsulating one or more battery cells. Optionally, the battery cell may include a lithium-ion secondary battery, a lithium-ion primary battery, a lithium-sulfur battery, a sodium-lithium-ion battery, a sodium-ion battery, or a magnesium-ion battery, etc., and the embodiments of this application are not limited thereto. Graphite can be used as the negative electrode active material of the battery cell, and in conjunction with the positive electrode active material of the battery cell, such as lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, to facilitate the movement of metal ions to form an electric current.

[0058] When producing graphite materials using a graphitization furnace, carbonaceous materials need to undergo a high-temperature reaction within the furnace's reaction chamber to be graphitized, thereby transforming them into more stable graphite materials. During the graphitization process within the reaction chamber, a large amount of high-temperature volatile matter is generated in the flue gas.

[0059] In related technologies, the treatment method for high-temperature flue gas involves connecting an external flue gas purification device to the graphitization furnace. This device directly draws out the high-temperature flue gas from the furnace, purifies it, and then discharges it directly to the outside. The temperature of the high-temperature flue gas discharged from the graphitization furnace is generally in the range of 800℃ to 1000℃, classifying it as ultra-high-temperature flue gas. This high-temperature flue gas contains not only H2S (hydrogen sulfide), pitch fumes, CO (carbon monoxide), and SO2 (sulfur dioxide), but also substantial solid components (heavy components such as petroleum coke and aromatic hydrocarbon mixtures). Therefore, using the above treatment method, the functional components of the flue gas purification device are easily damaged by the excessively high temperature of the flue gas. Furthermore, the purification device struggles to remove the solid components from the high-temperature flue gas, resulting in poor purification effects, difficulty in meeting emission standards, and significant environmental pollution.

[0060] Based on the above considerations, and to address the problems of current methods for treating high-temperature flue gas generated by graphitization furnaces, such as the susceptibility of functional components of the flue gas purification device to damage due to excessively high flue gas temperatures and poor purification efficiency, this application provides one or more embodiments of a flue gas treatment system. Through the coordinated arrangement of a cooling tower, an incinerator, and secondary treatment equipment, the cooling tower pre-cools and removes heavy components from the initial flue gas discharged from the graphitization furnace, reducing the temperature of the initial flue gas to a level that the functional components in the downstream incinerator and secondary treatment equipment can withstand. This reduces the probability of damage to these components due to excessively high flue gas temperatures. Simultaneously, by pre-removing heavy components from the initial flue gas through the cooling tower, the difficulty of heat recovery and purification of the flue gas in the downstream secondary treatment equipment is reduced. Thus, the purification efficiency of the downstream secondary treatment equipment is improved, ensuring that the discharged flue gas meets emission standards and reducing environmental pollution.

[0061] See Figure 1 and Figure 2 This application provides a flue gas treatment system for treating the initial flue gas discharged from the graphitization furnace 10. The flue gas treatment system includes a cooling tower 70, an incinerator 20, and secondary treatment equipment.

[0062] The cooling tower 70 is connected to the flue gas outlet of the graphitization furnace 10. The cooling tower 70 is used to cool the initial flue gas and remove heavy components from the initial flue gas.

[0063] The incinerator 20 is connected to the flue gas outlet of the cooling tower 70, and the incinerator 20 is used to burn the flue gas discharged from the cooling tower 70.

[0064] The secondary treatment equipment is connected to the flue gas outlet of the incinerator 20 and is used to recover the heat of the first flue gas discharged from the incinerator 20 and purify the first flue gas.

[0065] It should be noted that, in this application, cooling tower 70 refers to a device capable of cooling and reducing the temperature of the high-temperature initial flue gas discharged from graphitization furnace 10 and effectively removing heavy components from the initial flue gas. Cooling tower 70 may be, but is not limited to, counter-flow cooling tower, cross-flow cooling tower, packed cooling tower, and unpacked cooling tower.

[0066] Taking a packed cooling tower 70 as an example, the process of treating flue gas in cooling tower 70 is briefly described: Inside cooling tower 70, cooling water is sprayed upwards from the bottom of cooling tower 70, causing the sprayed water to form a water film on each layer of packing material inside cooling tower 70. The initial flue gas discharged from graphitization furnace 10 enters cooling tower 70 from the flue gas inlet at the top of cooling tower 70 and flows downwards through each layer of packing material inside cooling tower 70. When the initial flue gas passes through each layer of packing material, it comes into contact with the water film formed by the cooling water. The heat in the initial flue gas is absorbed by the water film, and the initial flue gas is cooled by the evaporation of water, thus achieving the cooling of the initial flue gas. During this process, heavy components in the initial flue gas (such as petroleum coke and aromatic hydrocarbon mixtures) are adsorbed by the cooling water and flow to the bottom of the tower with the cooling water, thereby removing heavy components from the initial flue gas.

[0067] It should be noted that by cooling the initial flue gas through the cooling tower 70, the initial flue gas temperature, which is in the range of 800℃ to 1000℃, can generally be reduced to the range of 100℃ to 300℃. This reduces the temperature of the initial flue gas to a level that the functional components in the downstream incinerator 20 and secondary treatment equipment can withstand, thereby reducing the probability of damage to the functional components in the incinerator 20 and secondary treatment equipment due to excessively high flue gas temperatures.

[0068] Meanwhile, by pre-removing heavy components from the initial flue gas through the cooling tower 70, the difficulty of heat recovery and purification of the flue gas by the downstream secondary treatment equipment is reduced, the purification effect of the downstream secondary treatment equipment on the flue gas is improved, and the flue gas discharged at the end meets the emission standards, reducing environmental pollution.

[0069] In this application, the incinerator 20 refers to a device capable of burning and oxidizing the flue gas discharged after being cooled by the cooling tower 70. The incinerator 20 may be, but is not limited to, a direct-fired furnace, a hot blast stove, etc., and the combustion medium may be one or more combinations of blast furnace gas, coke oven gas, converter gas, or natural gas.

[0070] Specifically, the incinerator 20 performs high-temperature combustion on the initial flue gas, oxidizing and burning H2S in the initial flue gas into H2O and SO2, oxidizing and burning asphalt fumes into H2O and CO2, oxidizing and burning CO into CO2, and oxidizing and burning organic matter into H2O and CO2. At this time, the first flue gas discharged from the incinerator 20 contains H2O, CO2, SO2, particulate matter, etc. The first flue gas is high-temperature flue gas and carries a large amount of heat.

[0071] It is understandable that the combustibles in the initial flue gas are burned by the incinerator 20, and the heat in the initial flue gas is fully released so that the heat of the flue gas can be efficiently recovered by the downstream secondary treatment equipment.

[0072] In this application, secondary treatment equipment refers to structural equipment capable of recovering heat and purifying the first flue gas discharged from the incinerator 20. The secondary treatment equipment may include a waste heat recovery device 30, a dust removal device 40, and a desulfurization device 50, which are connected sequentially via pipelines. The waste heat recovery device 30 can be configured as a waste heat boiler to recover heat from the flue gas; the dust removal device 40 can be configured as a bag filter to remove dust and particulate matter from the flue gas; and the desulfurization device 50 can be configured as a wet desulfurization tower to remove gaseous pollutants such as NOx, SO2, and SO3 from the flue gas.

[0073] Understandably, secondary treatment equipment recovers heat and purifies the primary flue gas. It not only recovers a large amount of heat from the flue gas, reduces direct heat loss, improves energy utilization, and reduces energy waste, but also performs secondary purification of the flue gas, ensuring that the flue gas discharged at the end meets emission standards and reduces environmental pollution.

[0074] It is easy to understand that the flue gas treatment system of this embodiment utilizes the coordinated arrangement of a cooling tower 70, an incinerator 20, and secondary treatment equipment. The cooling tower 70 pre-cools and lowers the initial flue gas discharged from the graphitization furnace 10, removing heavy components from the initial flue gas. This reduces the temperature of the initial flue gas to a level that the functional components in the downstream incinerator 20 and secondary treatment equipment can withstand, thereby reducing the probability of damage to these components due to excessively high flue gas temperatures. Simultaneously, by pre-removing heavy components from the initial flue gas through the cooling tower 70, the difficulty of heat recovery and purification of the flue gas by the downstream secondary treatment equipment is reduced. This improves the purification effect of the downstream secondary treatment equipment, ensuring that the flue gas discharged at the end meets emission standards and reduces environmental pollution.

[0075] In some embodiments of this application, see Figure 1 and Figure 2 The cooling tower 70 includes a tower body 71 and a spraying mechanism 72. The spraying mechanism 72 is located at the top or bottom of the tower body 71 and is used to spray a first cooling medium into the tower body 71.

[0076] Specifically, the first cooling medium is liquid water or water vapor.

[0077] The cooling tower 70 can be configured as a packed cooling tower or a packingless cooling tower. The spraying mechanism 72 includes a water storage tank at the bottom of the tower body 71, a water pump, and spray nozzles at the bottom or top of the tower body 71. The first cooling medium is cooling water in the water storage tank. The water pump delivers the cooling water in the water storage tank to the spray nozzles, so that the spray nozzles spray the cooling water from bottom to top or from bottom to top into the tower body 71. The cooling water forms a water film inside the tower body 71. The initial flue gas discharged from the graphitization furnace 10 enters the cooling tower 70 from the flue gas inlet at the top of the cooling tower 70 and comes into contact with the water film formed by the cooling water. The heat in the initial flue gas is absorbed by the water film, and the initial flue gas is cooled by the evaporation of water, thereby achieving the cooling of the initial flue gas. During this process, heavy components in the initial flue gas (such as petroleum coke and aromatic hydrocarbon mixtures) are adsorbed by the cooling water and flow to the bottom of the tower with the cooling water, thus removing heavy components in the initial flue gas.

[0078] Of course, in other embodiments, the spraying mechanism 72 can be directly set at the top inside the tower body 71. The spraying mechanism 72 introduces the first cooling medium outside the tower body 71 and then sprays the first cooling medium into the tower body 71 from top to bottom, which can also achieve the effect of cooling the initial flue gas and removing heavy components in the initial flue gas.

[0079] It is easy to understand that by spraying the first cooling medium into the tower body 71 through the spray mechanism 72, the first cooling medium inside the tower body 71 exchanges heat with the initial flue gas entering the tower body 71, reducing the temperature of the initial flue gas and decreasing the probability of damage to functional components in the downstream incinerator 20 and secondary treatment equipment due to excessively high flue gas temperatures. Simultaneously, the first cooling medium adsorbs and removes heavy components from the initial flue gas, reducing the difficulty of heat recovery and purification of the flue gas by the downstream secondary treatment equipment, improving the purification effect of the downstream secondary treatment equipment, ensuring that the exhaust gas meets emission standards, and reducing environmental pollution.

[0080] Further, see Figure 1 and Figure 2 Cooling pipes 73 are arranged on the periphery of the tower body 71, and the second cooling medium is circulated inside the cooling pipes 73.

[0081] Specifically, the cooling pipe 73 can be a water-cooled jacket installed on the inner or outer circumferential wall of the tower body 71, and a second cooling medium flows through the water-cooled jacket. The second cooling medium can be low-temperature pure water, low-temperature cooling oil, low-temperature nitrogen, low-temperature steam, etc.

[0082] For example, in some embodiments, the second cooling medium circulating in the water-cooled jacket is cooling water, with the water pressure controlled at 0.1MPa-1MPa, preferably at 0.3MPa-0.5MPa.

[0083] In other embodiments, the cooling medium flowing within the water-cooled jacket is low-temperature nitrogen or low-temperature steam, with the flow rate of the low-temperature nitrogen or low-temperature steam controlled at 10 m³ / h-50 m³ / h and the pressure controlled at 0.2 MPa-1 MPa, preferably controlled at 0.2 MPa-0.4 MPa.

[0084] When the initial flue gas discharged from the graphitization furnace 10 flows through the cooling tower 70, it comes into contact with the cooling pipes 73 on the periphery of the tower body 71 and exchanges heat with the second cooling medium inside the cooling pipes 73. This, combined with the cooling effect of the first cooling medium, accelerates the cooling efficiency of the initial flue gas. Furthermore, the water film formed on the wall of the cooling pipes 73 can also adsorb heavy components in the initial flue gas, further enhancing the removal efficiency of heavy components in the initial flue gas, in conjunction with the adsorption effect of the first cooling medium.

[0085] Further, see Figure 1 and Figure 2 The cooling tower 70 also includes a solid-liquid separation mechanism 74, which is located at the bottom of the tower body 71. The solid-liquid separation mechanism 74 is used to receive the solid-liquid mixture flowing down from the upper part of the tower body 71 and to separate the solid-liquid mixture.

[0086] Specifically, the solid-liquid separation mechanism 74 is a solid-liquid separator that operates based on the principle of centrifugal separation.

[0087] It is easy to understand that the first cooling medium inside the tower body 71 absorbs the heat of the initial flue gas inside the tower body 71 and adsorbs the heavy components in the initial flue gas, becoming a solid-liquid mixture composed of the liquid first cooling medium and the solid heavy components. The solid-liquid mixture falls to the bottom of the tower body 71 by gravity and is received by the solid-liquid separation mechanism 74 at the bottom of the tower body 71. The solid-liquid separation mechanism 74 separates the liquid first cooling medium and the solid heavy components in the solid-liquid mixture, thereby recovering the first cooling medium and the solid heavy components respectively.

[0088] See also some embodiments of this application. Figure 1 and Figure 2 The secondary treatment equipment includes a waste heat recovery device 30, a dust removal device 40, and a desulfurization device 50.

[0089] Waste heat recovery device 30 is connected to the flue gas outlet of incinerator 20. Waste heat recovery device 30 is used to exchange heat with the first flue gas discharged from incinerator 20 in order to recover the heat of the first flue gas.

[0090] The dust removal device 40 is connected to the flue gas outlet of the waste heat recovery device 30, and the dust removal device 40 is used to remove dust from the second flue gas discharged from the waste heat recovery device 30.

[0091] The desulfurization device 50 is connected to the flue gas outlet of the dust removal device 40. The desulfurization device 50 is used to desulfurize and denitrify the third flue gas discharged from the dust removal device 40.

[0092] In this application, the waste heat recovery device 30 refers to a device capable of exchanging heat with the first flue gas discharged from the incinerator 20 and absorbing the heat of the first flue gas to recover its heat. The waste heat recovery device 30 can be a waste heat hot water boiler assembly. After the first flue gas enters the waste heat hot water boiler assembly, the heat of the first flue gas exchanges heat with the water flowing in the heat exchange pipes of the waste heat hot water boiler assembly, heating the water to a certain temperature. The resulting hot water or steam can be used in other processes, such as for domestic heating or power generation. Of course, in other embodiments, the waste heat recovery device 30 can also be a thermal oil heat exchanger.

[0093] Understandably, the waste heat recovery device 30 recovers a large amount of heat from the first flue gas, reducing direct heat loss, improving energy utilization, and reducing energy waste. After the waste heat recovery device 30 recovers a large amount of heat from the first flue gas, the high-temperature first flue gas is cooled into a low-temperature second flue gas, which is then discharged from the flue gas outlet of the waste heat recovery device 30 to the dust removal device 40.

[0094] Dust removal device 40 refers to a device capable of removing dust and particulate matter from the second flue gas discharged from the waste heat recovery device 30, thereby filtering and purifying the second flue gas to ensure that the final emission of the flue gas meets emission standards. Dust removal device 40 can be, but is not limited to, a bag filter, a wet scrubber, an electrostatic precipitator, or a cyclone separator. For example, dust removal device 40 is a bag filter.

[0095] Understandably, after the dust removal device 40 removes dust from the second flue gas, the second flue gas is purified into a clean third flue gas, and the dust removal device 40 can transport the clean third flue gas to the desulfurization device 50 through the first induced draft fan 51.

[0096] The desulfurization unit 50 refers to a device capable of desulfurizing and denitrifying the third flue gas discharged from the dust removal unit 40, removing gaseous pollutants such as NOx, SO2, and SO3 from the third flue gas, achieving filtration and purification of the third flue gas, and ensuring that the flue gas emitted at the end meets emission standards. The desulfurization unit 50 preferably adopts a wet desulfurization tower.

[0097] Understandably, after the desulfurization and denitrification treatment of the third flue gas by the desulfurization unit 50, the third flue gas is purified into green and clean fourth flue gas. At this time, the fourth flue gas meets the emission standards, and the desulfurization unit 50 can discharge the green and clean fourth flue gas into the atmosphere through the chimney 52, thereby reducing environmental pollution.

[0098] It is easy to understand that the flue gas treatment system of this application embodiment, through the coordinated arrangement of an incinerator 20, a waste heat recovery device 30, a dust removal device 40, and a desulfurization device 50, allows the incinerator 20 to burn the combustibles in the initial flue gas discharged from the graphitization furnace 10, fully releasing the heat in the initial flue gas so that the downstream waste heat recovery device 30 can improve the heat recovery rate. The waste heat recovery device 30 recovers a large amount of heat from the first flue gas discharged from the incinerator 20, reducing direct heat loss, improving energy utilization, and reducing energy waste. The dust removal device 40 removes dust and particulate matter from the second flue gas discharged from the waste heat recovery device 30, achieving filtration and purification of the second flue gas. The desulfurization device 50 removes gaseous pollutants from the third flue gas discharged from the dust removal device 40, achieving filtration and purification of the third flue gas, ensuring that the flue gas emitted at the end meets emission standards. In this way, a large amount of heat in the high-temperature flue gas discharged from the graphitization furnace 10 is effectively recovered, improving energy utilization and reducing energy waste. Moreover, the high-temperature flue gas discharged from the graphitization furnace 10 is converted into clean, green flue gas that meets emission standards, reducing environmental pollution.

[0099] In some embodiments of this application, see Figure 1 and Figure 2 The waste heat recovery device 30 includes a waste heat boiler 31 and a high-temperature economizer 32 connected to the waste heat boiler 31. The waste heat boiler 31 is used to exchange heat with the first flue gas, and the high-temperature economizer 32 is used to exchange heat with the flue gas discharged from the waste heat boiler 31. The heat exchange pipeline of the high-temperature economizer 32 is connected to the steam drum 311 of the waste heat boiler 31, and the flue gas outlet of the high-temperature economizer 32 is connected to the dust removal device 40.

[0100] Specifically, the waste heat boiler 31 is a waste heat hot water boiler or a waste heat steam boiler. It can be understood that the waste heat boiler 31 has a flue gas inlet and a flue gas outlet. The first flue gas discharged from the incinerator 20 enters the waste heat boiler 31 through the flue gas inlet. Water in the heat exchange pipes of the waste heat boiler 31 exchanges heat with the first flue gas, absorbing heat from the first flue gas and turning into hot water or steam. The generated hot water or steam flows into the steam drum and can be used for heating, power generation, etc. In this way, the heat of the first flue gas is recovered.

[0101] The high-temperature economizer 32 can be, but is not limited to, a bare tube economizer or a finned economizer. The high-temperature economizer 32 is connected to the flue gas outlet of the waste heat boiler 31 through a pipe. After the first flue gas heats the water in the heat exchange pipe of the waste heat boiler 31, it cools down to form the first sub-flue gas. The first sub-flue gas then enters the high-temperature economizer 32 from the flue gas outlet of the waste heat boiler 31. The water in the heat exchange pipe of the high-temperature economizer 32 exchanges heat with the first sub-flue gas, absorbing the heat in the first sub-flue gas, causing the first sub-flue gas to cool down to the second sub-flue gas with a lower temperature. The water in the heat exchange pipe of the high-temperature economizer 32 is heated to a higher temperature hot water.

[0102] It should be noted that the waste heat boiler 31 also includes a steam drum 311, which is located at the top of the waste heat boiler 31 and is constructed as a cylindrical pressure vessel. The steam drum 311 is connected to the heat exchange pipelines of the waste heat boiler 31 and the heat exchange pipelines of the high-temperature economizer 32. The water in the heat exchange pipelines of the high-temperature economizer 32 is heated by the aforementioned first sub-flue gas and flows into the steam drum 311. The steam drum 311 receives the water from the high-temperature economizer 32 and distributes it to the heat exchange pipelines of the waste heat boiler 31.

[0103] In this way, increasing the feedwater temperature into the waste heat boiler 31 makes it easier for the water in the heat exchange pipes of the waste heat boiler 31 to be heated into steam by the first flue gas, thereby more effectively recovering and utilizing the heat energy in the first flue gas and improving the thermal efficiency of the waste heat boiler 31. At the same time, it can also reduce the wall temperature difference of the steam drum 311, thereby reducing the thermal stress on the wall of the steam drum 311 and extending the service life of the steam drum 311.

[0104] It is easy to understand that, through the combined structure of the waste heat boiler 31 and the high-temperature economizer 32, the first flue gas can be heat-exchanged twice in succession, which can more effectively recover and utilize the heat of the first flue gas discharged from the incinerator 20, and further improve the energy utilization rate.

[0105] Further, see Figure 1 and Figure 2 The waste heat recovery device 30 also includes a low-temperature economizer 33. The flue gas inlet of the low-temperature economizer 33 is connected to the flue gas outlet of the high-temperature economizer 32 for heat exchange with the flue gas discharged from the high-temperature economizer 32. The heat exchange pipeline of the low-temperature economizer 33 is connected to the steam drum 311 of the waste heat boiler 31. The flue gas outlet of the low-temperature economizer 33 is connected to the dust removal device 40.

[0106] Specifically, the low-temperature economizer 33 may be, but is not limited to, a bare tube economizer or a finned economizer.

[0107] Understandably, the low-temperature economizer 33 is connected to the flue gas outlet of the high-temperature economizer 32 via a pipeline. After the first flue gas undergoes two heat exchanges with the waste heat boiler 31 and the high-temperature economizer 32, a large amount of heat is recovered, and the flue gas discharged from the flue gas outlet of the high-temperature economizer 32 is the second sub-flue gas with a lower temperature.

[0108] The second flue gas enters the low-temperature economizer 33 from the flue gas outlet of the high-temperature economizer 32. Water in the heat exchange pipes of the low-temperature economizer 33 exchanges heat with the second flue gas, absorbing its heat and cooling it into a lower-temperature third flue gas. Meanwhile, the water in the heat exchange pipes of the low-temperature economizer 33 is heated to a higher temperature. This further recovers heat from the second flue gas, improving the heat recovery rate.

[0109] In addition, since the heat exchange pipeline of the low-temperature economizer 33 is connected to the steam drum 311 of the waste heat boiler 31, the water in the heat exchange pipeline of the low-temperature economizer 33 is heated by the second sub-flue gas mentioned above and flows into the steam drum 311. The steam drum 311 receives the water from the low-temperature economizer 33 and distributes it to the heat exchange pipeline of the waste heat boiler 31.

[0110] In conjunction with the aforementioned high-temperature economizer 32, the feedwater temperature entering the waste heat boiler 31 is increased, making it easier for the water in the heat exchange pipes of the waste heat boiler 31 to be heated into steam by the first flue gas. This allows for more effective recovery and utilization of the heat energy in the first flue gas, improving the thermal efficiency of the waste heat boiler 31. Simultaneously, it reduces the wall temperature difference of the steam drum 311, thereby reducing the thermal stress on the walls of the steam drum 311 and extending its service life.

[0111] It is easy to understand that, through the combined structure of the waste heat boiler 31, the high-temperature economizer 32 and the low-temperature economizer 33, the first flue gas can be heat-exchanged three times in a row, which can more effectively recover and utilize the heat of the first flue gas discharged from the incinerator 20, and further improve the energy utilization rate.

[0112] Further, see Figure 2 The heat exchange pipelines of the low-temperature economizer 33, the heat exchange pipelines of the high-temperature economizer 32, and the steam drum 311 of the waste heat boiler 31 are connected in sequence.

[0113] Specifically, the heat exchange pipes of the low-temperature economizer 33, the heat exchange pipes of the high-temperature economizer 32, and the steam drum 311 of the waste heat boiler 31 are connected in series via pipes. It is easy to understand that the medium flowing in the heat exchange pipes of the low-temperature economizer 33 and the heat exchange pipes of the high-temperature economizer 32 is water.

[0114] In this way, by sequentially connecting the heat exchange pipes of the low-temperature economizer 33, the heat exchange pipes of the high-temperature economizer 32, and the steam drum 311 of the waste heat boiler 31, the pipe layout between the three can be effectively simplified, and the water consumption supplied to the low-temperature economizer 33 and the high-temperature economizer 32 can be reduced accordingly.

[0115] Of course, in other embodiments, see Figure 2 The heat exchange pipelines of the high-temperature economizer 32, the heat exchange pipelines of the low-temperature economizer 33, and the steam drum 311 of the waste heat boiler 31 are connected in sequence.

[0116] Specifically, the heat exchange pipelines of the high-temperature economizer 32, the heat exchange pipelines of the low-temperature economizer 33, and the steam drum 311 of the waste heat boiler 31 are connected in series through pipelines.

[0117] Understandably, ambient temperature water first enters the heat exchange pipes of the high-temperature economizer 32, which is located closer to the waste heat boiler 31. The ambient temperature water in the heat exchange pipes of the high-temperature economizer 32 first exchanges heat with the first sub-flue gas discharged from the waste heat boiler 31, absorbing heat from the first sub-flue gas. The low-temperature economizer 33 is located at the rear end of the high-temperature economizer 32. It receives the second sub-flue gas discharged from the high-temperature economizer 32 and cooled by it. The temperature of the second sub-flue gas is lower than that of the first sub-flue gas. The water in the heat exchange pipes of the high-temperature economizer 32 is heated by the first sub-flue gas and then flows into the heat exchange pipes of the low-temperature economizer 33, where it is reheated by the second sub-flue gas, further recovering heat from the flue gas and reducing heat loss.

[0118] In this way, by sequentially connecting the heat exchange pipes of the high-temperature economizer 32, the heat exchange pipes of the low-temperature economizer 33, and the steam drum 311 of the waste heat boiler 31, not only is the pipe arrangement between the three components simplified, but the heat recovery of the high-temperature first flue gas can be more fully recovered, further improving the heat recovery rate and energy utilization rate.

[0119] Further, see Figure 3 The waste heat recovery device 30 also includes a high-temperature air preheater 34, the flue gas outlet of the high-temperature economizer 32, the flue gas inlet of the high-temperature air preheater 34, the flue gas outlet of the high-temperature air preheater 34 and the flue gas inlet of the low-temperature economizer 33 are connected in sequence, and the air outlet of the high-temperature air preheater 34 is connected to the flue gas inlet of the incinerator 20.

[0120] It should be noted that the high-temperature air preheater 34 can be, but is not limited to, a tube-type air preheater, a rotary air preheater, etc.

[0121] Taking a rotary high-temperature air preheater 34 as an example, the working principle of the high-temperature economizer 32, high-temperature air preheater 34, low-temperature economizer 33, and incinerator 20 is explained as follows: The rotor of the high-temperature air preheater 34 rotates, and the second-stage flue gas discharged from the high-temperature economizer 32 enters the high-temperature air preheater 34 through its flue gas inlet, and then exits from the flue gas outlet side of the high-temperature air preheater 34 into the low-temperature economizer 33. During the flow of the second-stage flue gas within the high-temperature air preheater 34, the heat carried in the second-stage flue gas is absorbed by the heat sink in the high-temperature air preheater 34. Then, the rotor of the high-temperature air preheater 34 rotates slowly, and the heat sink in the high-temperature air preheater 34 rotates to the air inlet side of the high-temperature air preheater 34. After absorbing the heat from the heat sink, the air enters the incinerator 20 from the air outlet of the high-temperature air preheater 34, thereby supplying the combustion medium to the incinerator 20.

[0122] Thus, the first flue gas discharged from the incinerator 20 flows sequentially through the waste heat boiler 31, the high-temperature economizer 32, the high-temperature air preheater 34, and the low-temperature economizer 33. After four heat exchanges, it becomes a low-temperature third flue gas and is discharged from the low-temperature economizer 33 into the dust removal device 40 for dust removal, efficiently recovering the heat from the first flue gas and significantly reducing the temperature of the flue gas entering the dust removal device 40. At the same time, the high-temperature air preheater 34 can also supply preheated air to the incinerator 20, which is beneficial to enhance the ignition and combustion process of the incinerator 20, allowing the combustibles in the initial flue gas to burn completely, improving the combustion efficiency of the incinerator 20, and correspondingly improving the heat release efficiency of the initial flue gas, which is beneficial to improving the heat recovery rate of the downstream waste heat recovery device 30.

[0123] Further, see Figure 3 The waste heat recovery device 30 also includes a low-temperature air preheater 35, which is located on the connecting pipeline between the low-temperature economizer 33 and the dust removal device 40. The air outlet of the low-temperature air preheater 35 is also connected to the flue gas inlet of the incinerator 20.

[0124] Specifically, the flue gas outlet of the high-temperature economizer 32, the flue gas inlet of the high-temperature air preheater 34, the flue gas outlet of the high-temperature air preheater 34, the flue gas inlet of the low-temperature economizer 33, the flue gas outlet of the low-temperature economizer 33, the flue gas inlet of the low-temperature air preheater 35, the flue gas outlet of the low-temperature air preheater 35, and the flue gas inlet of the dust removal device 40 are connected in series through pipelines.

[0125] It should be noted that the low-temperature air preheater 35 can be, but is not limited to, a tube-type air preheater, a rotary air preheater, etc.

[0126] Similarly, taking a rotary air preheater 35 as an example, the working principle of the low-temperature economizer 33, the low-temperature air preheater 35, and the incinerator 20 is explained: The rotor of the low-temperature air preheater 35 rotates, and the third-stage flue gas discharged from the low-temperature economizer 33 enters the low-temperature air preheater 35 through its flue gas inlet, and is then discharged to the dust removal device 40 from the flue gas outlet side of the low-temperature air preheater 35. During the flow of the third-stage flue gas within the low-temperature air preheater 35, the heat carried in the third-stage flue gas is absorbed by the heat sink in the low-temperature air preheater 35. Then, the rotor of the low-temperature air preheater 35 rotates slowly, and the heat sink in the low-temperature air preheater 35 rotates to the air inlet side of the low-temperature air preheater 35. After absorbing the heat from the heat sink, the air enters the incinerator 20 from the air outlet of the low-temperature air preheater 35, thereby supplying the combustion medium to the incinerator 20. The flue gas entering the dust removal device 40 is the second flue gas discharged from the low-temperature air preheater 35.

[0127] It is easy to understand that the first flue gas discharged from the incinerator 20 flows sequentially through the waste heat boiler 31, the high-temperature economizer 32, the high-temperature air preheater 34, the low-temperature economizer 33, and the low-temperature air preheater 35. After five heat exchanges, it becomes a low-temperature second flue gas and is discharged from the low-temperature economizer 33 into the dust removal device 40 for dust removal. This efficiently recovers the heat from the first flue gas and significantly reduces the temperature of the flue gas entering the dust removal device 40. At the same time, the high-temperature air preheater 34 and the low-temperature air preheater 35 can also supply preheated air to the incinerator 20, which helps to enhance the ignition and combustion process of the incinerator 20, allowing the combustibles in the initial flue gas to burn completely, improving the combustion efficiency of the incinerator 20, and correspondingly improving the heat release efficiency of the initial flue gas. This benefits the downstream waste heat recovery device 30 by increasing its heat recovery rate.

[0128] Further, see Figure 3 The air outlet of the low-temperature air preheater 35, the air inlet of the high-temperature air preheater 34, the air outlet of the high-temperature air preheater 34, and the flue gas inlet of the incinerator 20 are connected in sequence.

[0129] Specifically, the air outlet of the low-temperature air preheater 35, the air inlet of the high-temperature air preheater 34, the air outlet of the high-temperature air preheater 34, and the flue gas inlet of the incinerator 20 are connected in sequence through pipelines.

[0130] Of course, in other embodiments, the air outlet of the high-temperature air preheater 34, the air inlet of the low-temperature air preheater 35, the air outlet of the low-temperature air preheater 35, and the flue gas inlet of the incinerator 20 are connected in sequence.

[0131] The above configuration effectively simplifies the piping arrangement between the low-temperature air preheater 35, the high-temperature air preheater 34, and the incinerator 20, and also saves the amount of air supplied to the low-temperature air preheater 35 and the high-temperature air preheater 34.

[0132] In some embodiments of this application, see Figure 1 and Figure 2 The secondary treatment equipment also includes a pressure relief mechanism 60, which is installed on the connecting pipe between the flue gas outlet of the waste heat boiler 31 and the flue gas inlet of the high-temperature economizer 32.

[0133] Specifically, the pressure relief mechanism 60 can be configured as a pressure relief valve.

[0134] When a large amount of flue gas accumulates in the connecting pipe between the flue gas outlet of the waste heat boiler 31 and the flue gas inlet of the high-temperature economizer 32 due to abnormal operating conditions, the large amount of flue gas accumulated in the pipe can be discharged in time by opening the pressure relief mechanism 60, thereby reducing the risk of explosion caused by the accumulation of a large amount of flue gas.

[0135] It is easy to understand that by installing a pressure relief mechanism 60 on the connecting pipe between the flue gas outlet of the waste heat boiler 31 and the flue gas inlet of the high-temperature economizer 32, the safety and operational stability of the waste heat recovery device 30 can be improved.

[0136] In some embodiments of this application, see Figure 1 and Figure 2 The incinerator 20 is equipped with an igniter 21, which is used to ignite the incinerator 20 when the incinerator 20 is extinguished.

[0137] Specifically, igniter 21 is configured as a natural gas continuous lamp.

[0138] When the incinerator 20 experiences flameout during prolonged combustion, the igniter 21 automatically re-ignites the fuel gas within the incinerator 20, ensuring complete combustion of the combustibles and releasing the heat from the flue gas. Simultaneously, this reduces the probability of fuel gas accumulating within the incinerator 20 and causing an explosion, thus improving the safety and stability of the incinerator 20.

[0139] In addition, the inner wall of the incinerator 20 is provided with a refractory lining structure (not shown in the figure) to improve the refractory performance of the incinerator 20 and reduce the risk of the incinerator 20 being damaged by overheating when burning combustibles in the initial flue gas.

[0140] In addition, the incinerator 20 can use the second induced draft fan 22 to introduce the initial flue gas discharged from the cooling tower 70 into the incinerator 20, thereby accelerating the flow rate of the flue gas and thus improving the efficiency of flue gas treatment.

[0141] See also Figure 1 Based on the same concept as the flue gas treatment system described above, this application embodiment also provides a graphitization furnace 10, which includes the flue gas treatment system described above.

[0142] Understandably, during the graphitization process, carbonaceous materials undergo a high-temperature reaction in the reaction chamber 11 of the graphitization furnace, generating high-temperature initial flue gas. This high-temperature initial flue gas is discharged from the flue gas outlet of the graphitization furnace 10 and flows sequentially through the cooling tower 70, the incinerator 20, the waste heat boiler 31, the high-temperature economizer 32, the high-temperature air preheater 34, the low-temperature economizer 33, the low-temperature air preheater 35, the dust removal device 40, and the desulfurization device 50. After initial cooling and temperature reduction by the cooling tower 70, and full release of heat from the combustibles in the flue gas by the incinerator 20, the waste heat boiler 31, the high-temperature economizer 32, the high-temperature air preheater 34, the low-temperature economizer 33, and the low-temperature air preheater 35 recover and utilize the heat from the flue gas, and after the dust removal device 40 removes dust and particulate matter from the flue gas and the desulfurization device 50 removes gaseous pollutants from the flue gas, it is finally discharged as clean, green flue gas that meets emission standards.

[0143] In this way, a large amount of heat in the high-temperature flue gas discharged from the graphitization furnace 10 is effectively recovered, improving energy utilization and reducing energy waste. Moreover, the high-temperature flue gas discharged from the graphitization furnace 10 is converted into clean, green flue gas that meets emission standards, reducing environmental pollution.

[0144] In addition, based on the same concept as the graphitization furnace 10 described above, this application embodiment also provides a battery production apparatus, which includes the graphitization furnace 10 described above.

[0145] It is easy to understand that the battery production system of this application embodiment, due to the configuration of the above-mentioned graphitization furnace 10, also has the same technical effects brought by the graphitization furnace 10, that is, in the process of producing graphite materials for batteries, it reduces the probability of damage to the functional components in the incinerator 20 and secondary processing equipment due to the excessively high temperature of flue gas, improves the purification effect of the downstream secondary processing equipment on flue gas, and effectively recovers a large amount of heat in the high-temperature flue gas discharged from the graphitization furnace 10, improves energy utilization, reduces energy waste, and converts the high-temperature flue gas discharged from the graphitization furnace 10 into clean and green flue gas that meets emission standards, reducing environmental pollution.

[0146] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0147] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A flue gas treatment system for treating the initial flue gas discharged from a graphitization furnace, characterized in that, include: A cooling tower, connected to the flue gas outlet of the graphitization furnace, is used to cool the initial flue gas and remove heavy components from the initial flue gas. An incinerator, connected to the flue gas outlet of the cooling tower, is used to burn the flue gas discharged from the cooling tower; A secondary treatment device is connected to the flue gas outlet of the incinerator and is used to recover the heat of the first flue gas discharged from the incinerator and purify the first flue gas.

2. The flue gas treatment system according to claim 1, characterized in that, The cooling tower includes a tower body and a spraying mechanism. The spraying mechanism is located at the top or bottom of the tower body and is used to spray a first cooling medium into the tower body.

3. The flue gas treatment system according to claim 2, characterized in that, Cooling pipes are arranged on the periphery of the tower body, and a second cooling medium is circulated within the cooling pipes.

4. The flue gas treatment system according to claim 2, characterized in that, The cooling tower also includes a solid-liquid separation mechanism, which is located at the bottom of the tower body. The solid-liquid separation mechanism is used to receive the solid-liquid mixture flowing down from the upper part of the tower body and to separate the solid-liquid mixture.

5. The flue gas treatment system according to claim 1, characterized in that, The secondary processing equipment includes: A waste heat recovery device is connected to the flue gas outlet of the incinerator and is used to exchange heat with the first flue gas discharged from the incinerator in order to recover the heat of the first flue gas. A dust removal device is connected to the flue gas outlet of the waste heat recovery device and is used to remove dust from the second flue gas discharged from the waste heat recovery device. A desulfurization device is connected to the flue gas outlet of the dust removal device and is used to desulfurize and denitrify the third flue gas discharged from the dust removal device.

6. The flue gas treatment system according to claim 5, characterized in that, The waste heat recovery device includes a waste heat boiler and a high-temperature economizer connected to the waste heat boiler. The waste heat boiler is used to exchange heat with the first flue gas, and the high-temperature economizer is used to exchange heat with the flue gas discharged from the waste heat boiler. The heat exchange pipeline of the high-temperature economizer is connected to the steam drum of the waste heat boiler, and the flue gas outlet of the high-temperature economizer is connected to the dust removal device.

7. The flue gas treatment system according to claim 6, characterized in that, The waste heat recovery device also includes a low-temperature economizer. The flue gas inlet of the low-temperature economizer is connected to the flue gas outlet of the high-temperature economizer for heat exchange with the flue gas discharged from the high-temperature economizer. The heat exchange pipeline of the low-temperature economizer is connected to the steam drum of the waste heat boiler, and the flue gas outlet of the low-temperature economizer is connected to the dust removal device.

8. The flue gas treatment system according to claim 7, characterized in that, The heat exchange pipelines of the low-temperature economizer, the heat exchange pipelines of the high-temperature economizer, and the steam drum of the waste heat boiler are connected in sequence; and / or, The heat exchange pipelines of the high-temperature economizer, the heat exchange pipelines of the low-temperature economizer, and the steam drum of the waste heat boiler are connected in sequence.

9. The flue gas treatment system according to claim 7, characterized in that, The waste heat recovery device also includes a high-temperature air preheater. The flue gas outlet of the high-temperature economizer, the flue gas inlet of the high-temperature air preheater, the flue gas outlet of the high-temperature air preheater, and the flue gas inlet of the low-temperature economizer are connected in sequence. The air outlet of the high-temperature air preheater is connected to the flue gas inlet of the incinerator.

10. The flue gas treatment system according to claim 9, characterized in that, The waste heat recovery device also includes a low-temperature air preheater, which is located on the connecting pipeline between the low-temperature economizer and the dust removal device. The air outlet of the low-temperature air preheater is also connected to the flue gas inlet of the incinerator.

11. The flue gas treatment system according to claim 10, characterized in that, The air outlet of the low-temperature air preheater, the air inlet of the high-temperature air preheater, the air outlet of the high-temperature air preheater, and the flue gas inlet of the incinerator are sequentially connected; and / or, The air outlet of the high-temperature air preheater, the air inlet of the low-temperature air preheater, the air outlet of the low-temperature air preheater, and the flue gas inlet of the incinerator are connected in sequence.

12. The flue gas treatment system according to claim 6, characterized in that, The secondary treatment equipment also includes a pressure relief mechanism, which is installed on the connecting pipe between the flue gas outlet of the waste heat boiler and the flue gas inlet of the high-temperature economizer.

13. The flue gas treatment system according to any one of claims 1 to 12, characterized in that, The incinerator is equipped with an igniter, which is used to ignite the incinerator when it is shut down.

14. A graphitization furnace, characterized in that, Includes the flue gas treatment system as described in any one of claims 1 to 13.

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