Coal pyrolysis device

Abstract

The invention discloses a coal pyrolysis device. The coal pyrolysis device comprises a reaction tube, a feeding assembly, a heating assembly and a product collecting device, a low-temperature plasma high-voltage electrode is arranged in the reaction tube, a low-voltage electrode is arranged at the position, corresponding to the low-temperature plasma high-voltage electrode, of the outer portion of the reaction tube, a discharge area is arranged in the reaction tube, and a catalyst is arranged in the discharge area and used for assisting pulverized coal in activating hydrogen-rich gas in the pyrolysis process. The feeding assembly is communicated with the bottom of the reaction tube and conveys to-be-treated pulverized coal into the reaction tube for a pyrolytic reaction; the heating assembly is arranged on the periphery of the reaction tube and is used for heating the reaction tube; the product collecting device is connected with the top end of the reaction tube and is used for collecting gas-liquid-solid products generated by pyrolysis. According to the method, the catalyst assists the low-temperature plasma to activate the hydrogen-rich gas so as to strengthen fluidization and hydropyrolysis of the low-rank coal in situ, energy is provided for fracture of chemical bonds of the hydrogen-rich gas, the effective collision probability of active species and volatile free radicals is increased, and then the yield and quality of tar are improved.

Description

Technical Field

[0001] This application belongs to the field of coal pyrolysis technology, and specifically relates to a coal pyrolysis apparatus. Background Technology

[0002] It is estimated that low-rank coal reserves account for more than 42% of all coal reserves in my country, of which lignite accounts for about 14%. Currently, 90% of these coals are used for direct combustion. Industrial analysis of low-rank coal shows that volatile matter content is higher than 30%, but tar yield is low. The C / H ratio is high, and pyrolysis tar contains different fractions: below 180℃ is light oil, and above 360℃, the components are bitumen. The tar fraction required for the preparation of special fuels is 80% between 180℃ and 360℃. Improving the yield and selectivity of pyrolysis tar is a core issue of concern in coal pyrolysis research. Because low-rank coal contains a large amount of volatile matter, and the oil yield is less than half of the volatile matter, hydropyrolysis of low-rank coal can effectively suppress secondary reactions in pyrolysis and improve tar yield and quality. The gas produced by low-rank coal pyrolysis contains gases such as ethane, ethylene, H2, CH4, and CO2, which are natural hydrogen sources. CH4 and CO2 are typical greenhouse gases. The recycling and reuse of pyrolysis gas can not only improve the yield of tar, but also achieve efficient utilization of C and H elements in low-rank coal, thereby reducing the greenhouse effect.

[0003] However, in the hydropyrolysis process, the CH4 dissociation energy is 435 KJ / mol and the activation energy is 4.52 eV, making it difficult to activate. It is cracked at a high temperature of 880℃. The presence of a catalyst can reduce the activation energy of the reaction, but the temperature cannot match the optimal temperature range for coal pyrolysis to produce tar. Furthermore, the catalyst is in the coal sample, and there is a gas-solid two-phase reaction mass transfer problem in the hydropyrolysis process. Moreover, the catalyst is difficult to recover, which affects the further processing and utilization of semi-coke products, resulting in low tar yield. Summary of the Invention

[0004] The purpose of this application is to provide a coal pyrolysis apparatus to solve the technical problems of low tar yield and poor tar quality in traditional coal pyrolysis technology.

[0005] To achieve the above objectives, this application provides a coal pyrolysis apparatus, comprising: The reaction tube is equipped with a low-temperature plasma high-voltage electrode inside. A low-voltage electrode is provided on the outside of the reaction tube corresponding to the position of the low-temperature plasma high-voltage electrode. There is a discharge area inside the reaction tube, and a catalyst is provided in the discharge area. The catalyst is used to assist the coal powder in activating hydrogen-rich gas during the pyrolysis process. The feeding assembly is connected to the bottom of the reaction tube and is used to transport the coal powder to be processed into the reaction tube for pyrolysis reaction; A heating assembly is disposed on the outer periphery of the reaction tube and is used to heat the reaction tube; A product collection device is connected to the top of the reaction tube and is used to collect the gaseous, liquid and solid products generated by pyrolysis.

[0006] In some embodiments, the activation device further includes a variable diameter assembly disposed within the reaction tube, the variable diameter assembly being disposed near the top end of the reaction tube, one end of the variable diameter assembly being spaced apart from the top end of the low-temperature plasma high-voltage electrode, and the other end being connected to the product collection device, the distance between the end of the variable diameter assembly and the top end of the low-temperature plasma high-voltage electrode being adjustable.

[0007] In some embodiments, the variable diameter assembly includes: The variable diameter tube includes a variable diameter section and a straight tube section connected sequentially from top to bottom. The variable diameter section has an inverted funnel-shaped structure. The large end of the variable diameter section is open and faces the top of the low-temperature plasma high-voltage electrode. The outer peripheral wall of the variable diameter section is sealed to the inner peripheral wall of the reaction tube. The straight tube section and the reaction tube are arranged coaxially.

[0008] In some embodiments, the product collection device comprises, arranged sequentially from bottom to top: The semi-coke collection tube is used to collect the semi-coke product flowing out of the reaction tube; A sieve tube is connected to the top end of the semi-coke collecting tube. A sieve plate is provided inside the sieve tube. The top end of the reaction tube is located below the sieve plate. The sieve plate is used to separate the gas, solid and liquid discharged from the reaction tube. A liquid nitrogen condenser is provided, in which liquid nitrogen or ice water is poured as a condenser. The condenser is used to condense the volatiles passing through the condenser, so that the volatiles are condensed from the gas phase to the liquid phase. An exhaust pipe is provided inside the condenser, with one end of the exhaust pipe extending out of the top of the liquid nitrogen condenser and the other end passing through the bottom of the liquid nitrogen condenser and corresponding to the outlet end of the sieve tube.

[0009] In some embodiments, a fixing member is provided on the outer periphery of the liquid nitrogen condenser tube, the fixing member being used to fix the liquid nitrogen condenser tube and the sieve tube in a fixed connection.

[0010] In some embodiments, the top of the reaction tube is funnel-shaped, and the straight tube section extends through the top of the reaction tube. The end of the straight tube section opposite to the diameter-changing section is the outlet end. An umbrella-shaped shielding member is suspended from the outlet end of the straight tube section. The umbrella-shaped shielding member shields the top of the reaction tube, and a gap is left between the maximum outer edge of the umbrella-shaped shielding member and the semi-coke collecting tube. The umbrella-shaped shielding member is used to assist the raw coal and semi-coke flowing out of the straight tube section to fall into the semi-coke collecting tube.

[0011] In some embodiments, the top end of the reaction tube has a through tube communicating with the interior of the reaction tube. The through tube is located inside the semi-coke collecting tube and is spaced apart from the inner peripheral wall of the semi-coke collecting tube. The straight tube extends out of the top end of the reaction tube and passes through the through tube. The umbrella-shaped shielding member covers the top end of the through tube.

[0012] In some embodiments, the diameter of the straight tube is 1 / 4 to 1 / 2 of the diameter of the reaction tube.

[0013] In some embodiments, the bottom end of the reaction tube is sealed with a plug, one end of the low-temperature plasma high-voltage electrode is located inside the reaction tube, and the other end passes through the plug. The feeding assembly includes: Storage tank, containing pulverized coal awaiting processing; A pulverized coal conveying pipe is inserted into the storage tank at one end and passes through the sealing plug at the other end, which is located at the bottom of the reaction tube. The pulverized coal conveying pipe is used to transport gas carrying pulverized coal to be processed into the reaction tube.

[0014] In some embodiments, the heating component is a three-section vertical heating furnace, and the heating temperature range of the three-section vertical heating furnace is 450~700℃.

[0015] The above technical solution involves a low-temperature plasma high-voltage electrode inside the reaction tube, and a low-voltage electrode corresponding to the low-temperature plasma high-voltage electrode on the outside of the reaction tube. A discharge region is formed inside the reaction tube, and a catalyst is placed within the discharge region. The catalyst assists in activating hydrogen-rich gas during the pyrolysis process of pulverized coal. During the reaction, the catalyst can break down free radical fragments of the hydrogen-rich gas, thereby enabling the synergistic effect of the catalyst and the low-temperature plasma electrode to efficiently control the tar yield and quality. The feeding assembly is connected to the bottom of the reaction tube and is used to transport the pulverized coal to be processed into the reaction tube for pyrolysis. The heating assembly is located on the outer periphery of the reaction tube and is used to heat the reaction tube. The product collection device is connected to the top of the reaction tube and is used to collect the gaseous-liquid-solid products generated by pyrolysis. This application provides high-energy electrons for the activation of hydrogen-rich gas generated during coal pyrolysis by combining the low-temperature plasma high-voltage electrode and the low-voltage electrode. This can excite the hydrogen-rich gas generated during coal pyrolysis into active particles in advance, thereby achieving rapid sulfidation pyrolysis, reducing the reaction activation energy, improving the activation efficiency of hydrogen-rich components, and effectively controlling the degree of secondary reaction of volatiles, thus significantly increasing the tar yield of coal pyrolysis.

[0016] Other features and advantages of the embodiments of this application will be described in detail in the following detailed description section. Attached Figure Description

[0017] The accompanying drawings are provided to further illustrate the embodiments of this application and form part of the specification. They are used together with the following detailed description to explain the embodiments of this application, but do not constitute a limitation on the embodiments of this application. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without any inventive effort. In the drawings: Figure 1 This is a schematic diagram of the coal pyrolysis device of this application.

[0018] Explanation of reference numerals in the attached figures Detailed Implementation

[0019] The specific embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this application.

[0020] The coal pyrolysis apparatus according to this application is described below with reference to the accompanying drawings.

[0021] like Figure 1As shown, this application proposes a coal pyrolysis device. This technology is mainly applied to the pyrolysis process of low-rank coal activated by hydrogen-rich gases such as methane. By introducing a catalyst and low-temperature plasma in a synergistic effect, the hydrogen-rich gas is activated into active species, free radicals, and excited-state substances, stabilizing the free radicals in the volatile matter of low-rank coal pyrolysis tar. This effectively inhibits the cracking and polymerization of volatile free radicals, improving the tar yield and quality during the low-rank coal pyrolysis process, ensuring that the tar fraction is between 180 and 360°C, with the tar fraction above 360°C less than 40 wt.%. The hydrogen-rich gas originates from the components of the pyrolysis gas produced in low-rank coal. The coal pyrolysis unit includes a reaction tube 10, a feeding assembly, a heating assembly, and a product collection device. A low-temperature plasma high-voltage electrode 11 is installed inside the reaction tube 10, and a low-pressure electrode 12 is wound around the outside of the reaction tube 10 at the position corresponding to the low-temperature plasma high-voltage electrode 11. The low-temperature plasma high-voltage electrode 11 and the low-pressure electrode 12 work together to provide high-energy electrons for the activation of the hydrogen-rich gas generated during the coal pyrolysis process. This allows the hydrogen-rich gas generated during the coal pyrolysis process to be activated into active particles in advance, thereby achieving rapid sulfidation pyrolysis, reducing the reaction activation energy, and improving the activation efficiency of the hydrogen-rich components. This effectively controls the degree of secondary reaction of volatiles, resulting in a significant increase in the coal pyrolysis tar yield. Furthermore, a discharge region is formed inside the reaction tube 10 (this discharge region can be understood as the region of the reaction tube 10 where the low-temperature plasma high-voltage electrode 11 and the low-voltage electrode 12 are located). A catalyst 13 is provided in the discharge region. The catalyst 13 is used to assist the coal powder in activating the hydrogen-rich gas during the pyrolysis process. During the reaction, the catalyst 13 can break down the free radical fragments of the hydrogen-rich gas, thereby enabling the synergistic effect of the catalyst 13 and the low-temperature plasma electrode to efficiently control the tar yield and quality. The feeding assembly is connected to the bottom of the reaction tube 10 and is used to transport the coal powder to be processed into the reaction tube 10 for pyrolysis reaction. The heating assembly is located on the outer periphery of the reaction tube 10 and is used to heat the reaction tube 10. The product collection device is connected to the top of the reaction tube 10 and is used to collect the gaseous-liquid-solid products generated by pyrolysis.

[0022] As is well known, the mechanism of hydropyrolysis follows the free radical reaction mechanism. The main principle is to utilize the active species and free radicals of hydrogen-rich gas excited by high energy to stabilize the volatiles produced by the pyrolysis of low-rank coal, avoiding the disproportionation of primary tar volatiles, inhibiting the polymerization of medium-scale free radicals to form semi-coke or cracking into small molecule gases or light oil, thereby increasing the yield of pyrolysis tar and improving tar quality. Furthermore, traditional hydrogen-rich gas CH4 is sp3 hybridized, possessing a stable tetrahedral structure. Activating methane at 880℃ is not compatible with the coal pyrolysis temperature. Even with catalysts, activation of methane requires high temperatures, and the catalyst is prone to carbon deposition, leading to coking and deactivation.

[0023] To overcome the aforementioned limitations, this application introduces catalyst 13 and low-temperature plasma synergistically during coal fluidized pyrolysis to activate the hydrogen-rich gas generated in the coal pyrolysis reaction. The low-temperature plasma, through dielectric barrier discharge, can generate high-energy electrons and high-density active species at 100-300℃, achieving a conversion efficiency of CH4 and other hydrogen-rich gases that is greater than the sum of its parts (1+1>2). This significantly improves tar yield and quality while reducing semi-coke formation, thereby enhancing the overall conversion efficiency and economic value of coal resources. Furthermore, by using catalyst 13 to assist low-temperature plasma activation of hydrogen-rich gas to in-situ enhance the fluidized hydropyrolysis of low-rank coal, the activation energy of the reaction is lowered, increasing the effective collision probability between active species and volatile free radicals. Compared with traditional fixed-bed hydropyrolysis of low-rank coal, this method improves heat and mass transfer efficiency and reaction kinetics, achieving the goal of increasing tar yield and quality. It also has significant advantages over traditional high-energy-consuming and high-cost hydrogen activation methods.

[0024] Furthermore, experimental verification shows that the synergistic effect of catalyst 13 and low-temperature plasma on the activation of gas components is greater than that of catalyst 13 or low-temperature plasma alone, and its function of significantly reducing the activation energy of the reaction has been confirmed by a large number of experimental processes.

[0025] In a preferred embodiment, the catalyst 13 can be a glass fiber thin-tube liner impregnated with a transition metal or nitrate. This catalyst 13 has a large specific surface area, high mechanical strength, and high temperature resistance to assist in the stable discharge of the low-temperature plasma electrode. The transition metal can be Fe, Co, Ni, etc. Furthermore, in traditional pyrolysis processes, the catalyst 13 and coal are often mixed and laid flat, resulting in low separation efficiency. When the catalyst 13 and coal are laid flat, the active phase will decompose tar volatiles, transforming them into lighter oils, water, gases, and other products with smaller molecular weights. This application, by placing the catalyst 13 on the inner wall of the discharge region of the reaction tube 10, can better assist in activating the hydrogen-rich gas while reducing the decomposition of volatiles when the catalyst 13 is mixed with coal, and controlling the yield and quality of tar. Moreover, plasma technology can enhance the performance of the catalyst 13, reduce its deactivation, and thus lower maintenance costs.

[0026] In some embodiments, the activation device further includes a diameter-changing component disposed within the reaction tube 10. The diameter-changing component is positioned near the top of the reaction tube 10, with one end spaced apart from the top of the low-temperature plasma high-voltage electrode 11, and the other end connected to a product collection device. The product from the pyrolysis reaction of coal powder within the reaction tube 10 is collected by the product collection device through the diameter-changing component. In this embodiment, by providing a diameter-changing component within the reaction tube 10, the distance between the end of the component and the top of the low-temperature plasma high-voltage electrode 11 can be adjusted according to actual needs, thereby controlling the reaction residence time, increasing the heat and mass transfer of the reaction, and significantly improving the tar yield and quality.

[0027] In some embodiments, the variable diameter assembly includes a variable diameter capillary tube, which includes a variable diameter section 21 and a straight tube section 22 connected sequentially from top to bottom. The variable diameter section 21 has an inverted funnel-shaped structure, with its large end opening facing the top of the low-temperature plasma high-voltage electrode 11. This allows the hydrogen-rich gas generated by coal pyrolysis in the reaction tube 10 to completely enter the large end opening of the variable diameter section 21 and then enter the straight tube section 22 along the large end opening. The outer peripheral wall of the variable diameter section 21 is sealed to the inner peripheral wall of the reaction tube 10, and the straight tube section 22 is coaxially arranged with the reaction tube 10.

[0028] In this embodiment, the outer peripheral wall of the variable diameter section 21 and the inner peripheral wall of the reaction tube 10 are sealed and fixed with quartz wool. Furthermore, the straight tube section 22 is located at the center inside the reaction tube 10, and its length can be flexibly adjusted to suit experimental needs. Moreover, the residence time through the reaction can be adjusted by changing the height of the variable diameter tube, thereby suppressing secondary reactions in the pyrolysis reaction. Excessive residence time consumes more energy. This application reduces the energy efficiency of the entire pyrolysis process by optimizing the length of the straight tube section 22, shortens the mass transfer time of the reaction products to the collection device, and improves the tar yield and product selectivity.

[0029] In some embodiments, the product collection device includes a semi-coke collection pipe 31, a sieving pipe 32, and a liquid nitrogen placement pipe 33 arranged sequentially from bottom to top; the semi-coke collection pipe 31 is used to collect the semi-coke product flowing out of the reaction tube 10; the top ends of the sieving pipe 32 and the semi-coke collection pipe 31 are connected, and a sieve plate 321 is provided inside the sieve pipe 32. The top end of the reaction tube 10 is spaced below the sieve plate 321, and the sieve plate 321 is used to separate the gas, solid, and liquid discharged from the reaction tube 10; liquid nitrogen or ice water is poured into the liquid nitrogen placement pipe 33 as a condenser, and the condenser is used to condense the volatiles generated by pyrolysis. An exhaust pipe 34 is provided inside the liquid nitrogen placement pipe 33. One end of the exhaust pipe 34 extends out of the top end of the liquid nitrogen placement pipe 33, and the other end passes through the bottom end of the liquid nitrogen placement pipe 33 and is set corresponding to the outlet end of the sieving pipe 32. In this embodiment, the low-rank coal powder in the reaction tube 10 is pyrolyzed by the catalyst 13 and the low-temperature plasma electrode to generate hydrogen-rich gas. After pyrolysis, the hydrogen-rich gas carrying semi-coke and unreacted coal powder flows out through the top of the reaction tube 10. The sieve plate 321 is used to separate the solid and liquid and leave them in the sieve tube 32. The solid and liquid flow from the sieve tube 32 into the semi-coke collection tube 31. The gas after sieving by the sieve plate 321 enters the exhaust pipe 34. The volatiles are condensed into liquid tar and remain in the exhaust pipe and above the sieve plate, which is convenient for later cleaning and collection.

[0030] In some embodiments, a fixing member 35 is provided on the outer periphery of the liquid nitrogen placement tube 33, which is used to fix the liquid nitrogen placement tube 33 and the sieve tube 32. The fixing member 35 can be a cow horn for fixing. By using multiple fixing members 35, the position of the liquid nitrogen placement tube 33 is fixed to prevent it from tipping over during the experiment.

[0031] In some embodiments, the top of the reaction tube 10 is funnel-shaped, and a straight tube section 22 extends through the top of the reaction tube 10. The end of the straight tube section 22 opposite to the diameter-reducing section 21 is the outlet end. An umbrella-shaped shielding member 23 is suspended from the outlet end of the straight tube section 22. The umbrella-shaped shielding member 23 shields the top of the reaction tube 10, and a gap is left between the maximum outer edge of the umbrella-shaped shielding member 23 and the semi-coke collecting pipe 31. The umbrella-shaped shielding member 23 is used to assist the raw coal and semi-coke flowing out of the straight tube section 22 to fall into the semi-coke collecting pipe 31. In this embodiment, the raw coal and semi-coke flowing out of the top of the straight tube section 22 fall onto the outer peripheral wall of the umbrella-shaped shielding member 23 and slide down along the outer peripheral wall of the umbrella-shaped shielding member 23 into the semi-coke collecting pipe 31, thereby achieving the collection of semi-coke and raw coal. The remaining semi-coke, injected upwards along with the gas, is sieved by the sieve plate 321 and returned to the semi-coke collection pipe 31. The gas then passes through the sieve plate 321 into the exhaust pipe 34, where it is condensed by the liquid nitrogen placement pipe 33 and the tar is collected. This application, through the design of this integrated-separated product collection device, shortens the mass transfer distance of the product and effectively achieves gas-solid-liquid separation. This technical solution not only improves the economic benefits of coal pyrolysis but also promotes the advancement of clean coal utilization technology.

[0032] In some embodiments, the top end of the reaction tube 10 has a connecting pipe 36 communicating with the interior of the reaction tube 10. The connecting pipe 36 is located inside the semi-coke collecting pipe 31 and is spaced apart from the inner peripheral wall of the semi-coke collecting pipe 31. A straight pipe portion 22 extends out of the top end of the reaction tube 10 and passes through the connecting pipe 36. An umbrella-shaped shielding member 23 covers the top end of the connecting pipe 36. In this embodiment, the raw coal and semi-coke injected from the top end of the straight pipe portion 22 slide down along the outer peripheral wall of the umbrella-shaped shielding member 23 into the gap between the connecting pipe 36 and the semi-coke collecting pipe 31, thereby allowing the raw coal and semi-coke to be collected inside the semi-coke collecting pipe 31.

[0033] In some embodiments, the diameter of the straight pipe section 22 is 1 / 4 to 1 / 2 of the diameter of the reaction tube 10. Preferably, the diameter of the straight pipe section 22 is 1 / 3 of the diameter of the reaction tube 10. With this size optimization, the volatiles generated by coal pyrolysis can be quickly discharged from the straight pipe section 22 to suppress secondary reactions and increase the tar yield.

[0034] In some embodiments, the bottom end of the reaction tube 10 is sealed with a sealing plug 53. One end of the low-temperature plasma high-voltage electrode 11 is located inside the reaction tube 10, and the other end passes through the sealing plug 53. The feeding assembly includes a storage tank 51 and a pulverized coal conveying pipe 52. The storage tank 51 stores pulverized coal to be processed. One end of the pulverized coal conveying pipe 52 is inserted into the storage tank 51, and the other end passes through the sealing plug 53 and is located at the bottom of the reaction tube 10. The pulverized coal conveying pipe 52 is used to transport gas carrying the pulverized coal to be processed into the reaction tube 10. In this embodiment, the storage tank 51 and the pulverized coal conveying pipe 52 together form the feeding structure. Gas and other carrier gases enter the storage tank through a 6mm outer diameter stainless steel pipe at a flow rate of 1-3L / min, carrying the pulverized coal in the storage tank 51, and enter the reaction tube 10 through the 3mm outer diameter stainless steel pulverized coal conveying pipe 52 for pyrolysis reaction. The sealing plug 53 is a polytetrafluoroethylene plug used to fix the low-temperature plasma high-voltage electrode 11 and the pulverized coal conveying pipe 52.

[0035] In some embodiments, the reaction tube 10 is made of quartz material, and the quartz reaction tube 10 serves as a single-layer dielectric required for discharge, so as to achieve stable discharge of the high-voltage electrode and the low-voltage electrode 12 during coal pyrolysis.

[0036] In some embodiments, the heating component is a three-stage vertical heating furnace 40, the heating temperature range of which is 450~700°C, which is the reaction temperature of the coal pyrolysis reaction, and can be used to provide the required heat source for the pyrolysis of low-rank coal.

[0037] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0038] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," 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, an electrical connection, or a connection that allows communication between components; 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.

[0039] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0040] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A coal pyrolysis apparatus, characterized in that, include: The reaction tube (10) is provided with a low-temperature plasma high-voltage electrode (11) inside. A low-pressure electrode (12) is provided on the outside of the reaction tube (10) corresponding to the position of the low-temperature plasma high-voltage electrode (11). The reaction tube (10) has a discharge area inside. A catalyst (13) is provided in the discharge area. The catalyst (13) is used to assist the coal powder in activating hydrogen-rich gas during the pyrolysis process. The feeding assembly is connected to the bottom of the reaction tube (10) and is used to transport the coal powder to be processed into the reaction tube (10) for pyrolysis reaction; A heating assembly is disposed on the outer periphery of the reaction tube (10) and is used to heat the reaction tube (10); A product collection device is connected to the top of the reaction tube (10) and is used to collect the gaseous-liquid-solid products generated by pyrolysis.

2. The coal pyrolysis apparatus according to claim 1, characterized in that, The activation device also includes a variable diameter assembly disposed in the reaction tube (10). The variable diameter assembly is disposed near the top end of the reaction tube (10). One end of the variable diameter assembly is spaced apart from the top end of the low-temperature plasma high-voltage electrode (11), and the other end is connected to the product collection device. The distance between the end of the variable diameter assembly and the top end of the low-temperature plasma high-voltage electrode (11) is adjustable.

3. The coal pyrolysis apparatus according to claim 2, characterized in that, The variable diameter assembly includes: The variable diameter tube includes a variable diameter section (21) and a straight tube section (22) connected sequentially from top to bottom. The variable diameter section (21) has an inverted funnel-shaped structure. The large end of the variable diameter section (21) is open and faces the top of the low-temperature plasma high-voltage electrode (11). The outer peripheral wall of the variable diameter section (21) and the inner peripheral wall of the reaction tube (10) are sealed together. The straight tube section (22) and the reaction tube (10) are arranged coaxially.

4. The coal pyrolysis apparatus according to claim 3, characterized in that, The product collection device comprises, arranged sequentially from bottom to top: The semi-coke collection tube (31) is used to collect the semi-coke product flowing out of the reaction tube (10); The top end of the sieve tube (32) is connected to the top end of the semi-coke collection tube (31). The sieve tube (32) is provided with a sieve plate (321). The top end of the reaction tube (10) is located below the sieve plate (321). The sieve plate (321) is used to separate the gas-solid-liquid mixture discharged from the reaction tube (10). A liquid nitrogen placement tube (33) is provided with a condenser and an exhaust pipe (34). The condenser is used to condense the volatiles passing through the exhaust pipe (34) so ​​that the volatiles are condensed from the gas phase to the liquid phase. One end of the exhaust pipe (34) extends out of the top of the liquid nitrogen placement tube (33), and the other end passes through the bottom of the liquid nitrogen placement tube (33) and is set at the outlet end of the sieve tube (32).

5. The coal pyrolysis apparatus according to claim 4, characterized in that, The liquid nitrogen placement tube (33) is provided with a fixing member (35) on its outer periphery, which is used to fix the liquid nitrogen placement tube (33) and the screening tube (32) together.

6. The coal pyrolysis apparatus according to claim 4, characterized in that, The top of the reaction tube (10) is funnel-shaped. The straight tube section (22) is installed through the top of the reaction tube (10). The end of the straight tube section (22) away from the variable diameter section (21) is the outlet end. An umbrella-shaped shield (23) is suspended at the outlet end of the straight tube section (22). The umbrella-shaped shield (23) shields the top of the reaction tube (10), and there is a gap between the maximum outer edge of the umbrella-shaped shield (23) and the semi-coke collection tube (31). The umbrella-shaped shield (23) is used to assist the raw coal and semi-coke flowing out from the straight tube section (22) to fall into the semi-coke collection tube (31).

7. The coal pyrolysis apparatus according to claim 6, characterized in that, The top end of the reaction tube (10) has a connecting tube (36) that communicates with the interior of the reaction tube (10). The connecting tube (36) is located inside the semi-coke collecting tube (31) and is spaced apart from the inner peripheral wall of the semi-coke collecting tube (31). The straight tube (22) extends out of the top end of the reaction tube (10) and passes through the connecting tube (36). The umbrella-shaped shield (23) covers the top end of the connecting tube (36).

8. The coal pyrolysis apparatus according to claim 3, characterized in that, The diameter of the straight tube (22) is 1 / 4 to 1 / 2 of the diameter of the reaction tube (10).

9. The coal pyrolysis apparatus according to any one of claims 1 to 8, characterized in that, The bottom end of the reaction tube (10) is sealed with a sealing plug (53). One end of the low-temperature plasma high-voltage electrode (11) is located inside the reaction tube (10), and the other end is disposed through the sealing plug (53). The feeding assembly includes: Storage tank (51) contains coal powder to be processed; The coal powder conveying pipe (52) is inserted into the storage tank (51) at one end and passes through the sealing plug (53) at the other end and is located at the bottom of the reaction tube (10). The coal powder conveying pipe (52) is used to transport gas carrying coal powder to be processed into the reaction tube (10).

10. The coal pyrolysis apparatus according to any one of claims 1 to 8, characterized in that, The heating component is a three-section vertical heating furnace (40), and the heating temperature range of the three-section vertical heating furnace (40) is 450~700℃.

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