Pyrolysis reactor, carbonaceous material fast pyrolysis system and method for carbonaceous material fast pyrolysis

Abstract

The present application relates to coal pyrolysis technical field, disclose a kind of pyrolysis reactor, carbonaceous raw material rapid pyrolysis system and carbonaceous raw material rapid pyrolysis method, the pyrolysis reactor includes vertically arranged activation reaction section and horizontally arranged activation stabilization section, activation reaction section and activation stabilization section are connected in series along the flow direction;From bottom to top, the activation reaction section includes mixing zone and reaction lifting zone;Wherein, the mixing zone contains a first-order venturi structure, and the activation stabilization section contains a second-order venturi structure;Throat of first-order venturi structure and second-order venturi structure is respectively provided with at least one supplementary gas inlet, and activation device and / or activation material are arranged at the supplementary gas inlet, for the activation of supplementary gas, the inlet section of first-order venturi structure is provided with carbonaceous raw material and lifting gas inlet, and the outlet section of second-order venturi structure is provided with pyrolysis product outlet.Using the pyrolysis reactor can realize the process controllable of carbonaceous raw material pyrolysis process oil yield improvement.

Description

Technical Field

[0001] This invention relates to the field of coal pyrolysis technology, specifically to a pyrolysis reactor, a rapid pyrolysis system for carbonaceous raw materials, and a method for rapid pyrolysis of carbonaceous raw materials. Background Technology

[0002] Currently, the thermal conversion of carbonaceous raw materials such as waste plastics, coal, and biomass aims to increase the yield of liquid products. For example, the main development direction in the field of low-rank coal fractionation is high oil yield and large-scale industrialization. However, in actual industrial processes, pyrolysis technology is prone to blockages. This is mainly because, whether the pyrolysis reaction proceeds in a single pass or enters a circulating system, it is necessary to address the fluctuations in gas velocity or other operating conditions caused by the additional gas produced in situ. However, when the gas-solid mixture enters the gas-solid separation unit, these fluctuations in gas velocity and other operating conditions will cause system instability.

[0003] Specifically, pyrolysis technology can employ various methods such as rotary kilns, fixed beds, and fluidized beds. However, the oil yield is often low, primarily due to severe material accumulation, which hinders the escape of volatiles during programmed temperature rise and leads to severe secondary reactions such as coking. Current advanced pyrolysis technologies aim to improve oil yield by reducing powder particle density, adding gases and solid heat carriers to enhance heat transfer, and combining the characteristics of rapid reaction beds like fluidized beds. This increases the rate of rapid volatile removal, reduces the probability of secondary reactions, and improves the overall oil yield. Despite current technologies optimizing mass and heat transfer, the oil yield still hasn't reached its maximum, mainly because free radicals haven't been stabilized in time. Therefore, a hydrogen-rich gas or other raw materials that can generate free radicals are proposed to activate and couple the pyrolysis reaction, stabilizing volatiles to increase liquid product production. Simultaneously, the velocity and temperature fields are effectively controlled during the replenishment of hydrogen-rich gases. Thus, by coupling strategies such as hydrogenation, gaseous heat carriers, fluidized beds, gas activation, and online rapid separation of products to improve oil yield, the oil yield of carbonaceous feedstock pyrolysis can be increased and the process can be made more controllable. Summary of the Invention

[0004] The purpose of this invention is to overcome the problem of low liquid product yield in the pyrolysis reaction of carbonaceous materials in the prior art, and to provide a pyrolysis reactor, a rapid pyrolysis system for carbonaceous raw materials, and a method for rapid pyrolysis of carbonaceous raw materials. Using this pyrolysis reactor, the oil yield in the pyrolysis process of carbonaceous raw materials can be improved and the process can be controlled.

[0005] The inventors of this invention discovered during their research that pyrolysis technology is very difficult to control in existing industrial processes, and the system is prone to coking. One major reason may be that the raw materials used are usually high-volatile materials, such as oil-rich low-rank coal. Oil-rich low-rank coal typically produces a large amount of chain hydrocarbons during the conversion process. These hydrocarbons undergo C / C bond breakage during heat recovery to generate olefins, and olefin products are one of the causes of coking in the system. Another major reason for coking is the generation of high-boiling-point polycyclic aromatic hydrocarbon free radicals during the conversion process. These free radicals not only easily become liquid upon cooling but are also unstable and prone to condensation. To minimize the occurrence of such problems, substances that stabilize various free radicals can be added to the system.

[0006] However, this approach also presents other problems.

[0007] On the one hand, substances that readily stabilize free radicals are typically difficult to activate within a pyrolysis temperature window of 500-600℃ during the matching chemical field process, making it difficult for them to achieve their desired effects. To solve this problem, it is necessary to add catalysts or plasma activation devices to the system.

[0008] On the other hand, hydrogenation is typically an exothermic process, while pyrolysis is usually an endothermic process. In systems where hydrogenation and pyrolysis are coupled, temperature instability within the reaction space is common. If the operating conditions fluctuate significantly, large fluctuations in the gas-solid ratio and gas velocity will occur. In such cases, the device itself needs strong resistance to fluctuations, requiring continuous control of gas flow rate and velocity within the reaction system.

[0009] Based on this, we simultaneously controlled the reaction field of free radicals, the temperature field and the velocity field within the reaction range when using gas and activation methods, thereby generating a rapid pyrolysis process technology that is resistant to the risk of operating condition fluctuations.

[0010] To achieve the above objectives, a first aspect of the present invention provides a pyrolysis reactor, the pyrolysis reactor comprising a vertically arranged activation reaction section and a horizontally arranged activation stabilization section, the activation reaction section and the activation stabilization section being connected in series along the material flow direction; From bottom to top, the activation reaction section includes a mixing zone and a reaction enhancement zone; wherein, the mixing zone contains a first-order Venturi structure, and the activation stabilization section contains a second-order Venturi structure; At least one supplementary gas inlet is provided at the throat of both the primary and secondary Venturi structures. The supplementary gas inlet is equipped with an activation device and / or activation material for activating the supplementary gas. The inlet section of the primary Venturi structure is equipped with a carbonaceous raw material and a booster gas inlet, and the outlet section of the secondary Venturi structure is equipped with a pyrolysis product outlet.

[0011] A second aspect of the present invention provides a rapid pyrolysis system for carbonaceous raw materials, the system comprising a pulverizing unit, a gasification unit, a pyrolysis unit, a dust removal unit, and a fractionation unit connected sequentially along the material flow direction; the pyrolysis unit comprises the aforementioned pyrolysis reactor; The pulverizing unit is used to screen carbonaceous raw materials and includes a fine particle outlet and a coarse particle outlet. The inlet of the gasification unit is connected to the fine particle outlet of the pulverizing unit and is used to gasify the screened fine particles. The dust removal unit is connected to the pyrolysis product outlet of the pyrolysis unit and is used to separate the pyrolysis products into gas and solid phases. The dust removal unit has an oil and gas outlet and a solid phase outlet. The oil and gas outlet is connected to the fractionation unit, and the solid phase outlet is connected to the inlet of the gasification unit. The fractionation unit includes at least one fractionation tower for fractionating the oil and gas from the dust removal unit. The carbonaceous raw material and booster gas inlets of the pyrolysis unit are connected to the coarse particle outlet of the pulverizing unit, the top outlet of the fractionation tower, and the gasification gas outlet of the gasification unit.

[0012] A third aspect of the present invention provides a method for rapid pyrolysis of carbonaceous raw materials, the method being carried out in the aforementioned system and comprising: S1. The carbonaceous raw material is sieved to obtain particulate component I with a particle size of 0.06-0.3 mm and particulate component II with a particle size <0.06 mm; S2. Gasify the particulate component II with a particle size <0.06mm to obtain gasified gas and gasified slag; S3. In the presence of booster gas, particulate component I with a particle size of 0.06-0.3 mm is fed into the pyrolysis reactor, and supplementary gas is fed into the pyrolysis reactor through the supplementary gas inlets of the primary Venturi structure and the secondary Venturi structure to carry out the pyrolysis reaction. The booster gas is provided by at least one of gasification gas, pyrolysis gas, hydrogen-rich gas, or inert gas; S4. The pyrolysis reaction products are separated by dust removal to obtain oil and gas; S5. The oil and gas are fractionated to obtain pyrolysis gas.

[0013] Through the above technical solutions, the present invention has designed a structure for the pyrolysis reactor, coupled fluidized bed pyrolysis and fluidized bed gasification, and adopted hydrogen activation coupling technology in the pressurized fluidized bed pyrolysis section to achieve multi-field coupling and control. Gas activation and other process methods have been added to the system process, and the purpose of relatively independent units has been achieved in the reaction process. Furthermore, other technologies can be nested and coupled in this process.

[0014] The integrated pyrolysis system provided by this invention features rapid pyrolysis via multi-field coupling in a fluidized bed, enabling the production of high-quality tar, semi-coke, and coal gas under a controllable atmosphere. The fluidized bed pyrolysis unit is a single-pass gaseous heat carrier pyrolyzing low-rank coal, resulting in a short system flow and simple operation. The pyrolysis unit is coupled with controllable combustion and gasification systems for semi-coke, exhibiting high system maturity and flexible module combination. A hydrogen-rich atmosphere is constructed by adjusting the circulating gas composition, and hydrogen-rich activation technology is integrated to achieve reaction atmosphere control. The multi-product pathway is clear, enabling high system integration. It is easily scalable for large-scale industrialization and can be integrated with existing gasification processes, resulting in low unit investment. It offers high flexibility in scale adjustment, allowing for large-scale replication and making it suitable for industries such as chemical, power, and metallurgy, demonstrating strong adaptability to various scenarios. It is highly adaptable to different types of raw coal, providing a reliable technical path for the regional on-site conversion of low-rank coal. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the pyrolysis reactor in this invention; Figure 2 This is a schematic diagram of the structure of the rapid pyrolysis system for carbonaceous raw materials in this invention.

[0016] Explanation of reference numerals in the attached figures 1. Powdering unit 2. Pyrolysis unit 3 dust removal units 4 fractionation units 5. Gasification unit; 6. Gas mixing and distribution device Detailed Implementation The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0017] The first aspect of the present invention provides a pyrolysis reactor, the pyrolysis reactor comprising a vertically arranged activation reaction section and a horizontally arranged activation stabilization section, the activation reaction section and the activation stabilization section being connected in series along the material flow direction; From bottom to top, the activation reaction section includes a mixing zone and a reaction enhancement zone; wherein, the mixing zone contains a first-order Venturi structure, and the activation stabilization section contains a second-order Venturi structure; At least one supplementary gas inlet is provided at the throat of both the primary and secondary Venturi structures. The supplementary gas inlet is equipped with an activation device and / or activation material for activating the supplementary gas. The inlet section of the primary Venturi structure is equipped with a carbonaceous raw material and a booster gas inlet, and the outlet section of the secondary Venturi structure is equipped with a pyrolysis product outlet.

[0018] In this invention, such as Figure 1As shown, the pyrolysis reactor includes a vertically arranged activation reaction section and a horizontally arranged activation stabilization section, which are connected in series along the material flow direction. The activation reaction section and the activation stabilization section can be connected in a manner conventional in the art, such as using a bent pipe or a right-angle pipe; the present invention does not have any particular requirements in this regard.

[0019] In a preferred embodiment, the pyrolysis reactor consists of a vertically arranged activation reaction section, a connecting bend, and a horizontally arranged activation stabilization section.

[0020] The present invention does not impose any particular limitation on the shape of the pyrolysis reactor, which can generally be tubular. The diameter of the pyrolysis reactor is related to the raw material processing capacity, and those skilled in the art can adjust it according to actual needs.

[0021] According to the present invention, the relative lengths of the activation reaction section and the activation stabilization section can be adjusted according to the scale of the device and the type of coal being processed. Preferably, the length ratio of the activation reaction section to the activation stabilization section is 1:0.001-0.5, more preferably 1:0.01-0.1.

[0022] In this invention, from bottom to top, the activation reaction section includes a mixing zone and a reaction enhancement zone. Preferably, the height of the reaction enhancement zone accounts for 50-80% of the total height of the activation reaction section, and more preferably 60-70%. Under these preferred conditions, it is beneficial to increase the residence time, improve the stabilization process of free radicals, and achieve better oil stability.

[0023] Preferably, from bottom to top, the reaction enhancement zone includes a constant diameter section, a reduced diameter section, and a narrow diameter section, wherein the inner diameter of the constant diameter section is the same as the inner diameter at the outlet of the outlet section of the first-stage Venturi structure.

[0024] Preferably, the ratio of the inner diameter of the equal diameter section to the narrow diameter section is 1:(0.1-1), and more preferably 1:(0.2-0.5).

[0025] Preferably, the height ratio of the equal diameter section, the reduced diameter section, and the narrow diameter section is 1:0.01-1:0.01-1, and more preferably 1:0.05-0.1:0.2-0.5.

[0026] In this invention, the mixing zone contains a primary Venturi structure, which includes an inlet section, a contraction section, a throat, and a diffusion section. At least one supplementary gas inlet is provided at the throat of the primary Venturi structure, and the supplementary gas inlet is equipped with an activation device and / or activation material for activating the supplementary gas. The inlet section of the primary Venturi structure is equipped with a carbonaceous raw material and a booster gas inlet. In this invention, this component enables in-situ activation of the gas and comprehensive temperature control, thereby achieving free radical stabilization in the reaction process.

[0027] More preferably, in the primary Venturi structure, the ratio of the inner diameter of the throat to the inner diameter at the entrance of the inlet segment is 1:(10-100), more preferably 1:(40-70).

[0028] Preferably, the ratio of the length of the larynx to the inner diameter of the larynx is 0.1-5:1, more preferably 0.5-2:1.

[0029] Preferably, in the primary Venturi structure, the cone angle of the contraction section is 10-80°, more preferably 15-75°, and even more preferably 50-75°.

[0030] Preferably, in the primary Venturi structure, the cone angle of the diffusion section is 10-80°, more preferably 15-75°, and even more preferably 50-75°.

[0031] The preferred first-stage Venturi structure described above helps to increase the mixing intensity during material conveying, ensuring thorough mixing of materials and thus further improving the heat transfer effect.

[0032] In this invention, at least one supplementary air inlet is provided at the throat of the primary Venturi structure; preferably, 1-4 supplementary air inlets are provided at the throat of the primary Venturi structure. Preferably, the supplementary air inlets are evenly distributed along the circumference of the throat.

[0033] According to the present invention, the activation device or activation material is a device or material capable of achieving in-situ activation with supplemental gas, and those skilled in the art can select it according to actual needs. Preferably, the activation device is an internal electrode and / or a plasma device. Preferably, the activation material is a plasma and / or an activation catalyst.

[0034] According to the present invention, the activation and stabilization section contains a secondary Venturi structure, and at least one supplementary gas inlet is provided at the throat of the secondary Venturi structure. This structure increases the residence time of the semi-coke, enabling the reforming or stabilization of volatile free radicals precipitated from the carbonaceous feedstock, thereby improving the stability of primary products and reducing coking potential. Simultaneously, this structure helps achieve oil product stability. Furthermore, the gas supplementation process enables velocity field regulation, and the temperature control of the activated gas allows for temperature control of the primary coal pyrolysis products, ensuring that they do not experience coking problems due to temperature drops causing the precipitation of heavy tar.

[0035] According to some preferred embodiments of the present invention, the secondary Venturi structure includes an inlet section, a constriction section, a throat, and a diffuser section. Preferably, in the secondary Venturi structure, the ratio of the inner diameter of the throat to the inner diameter at the inlet of the inlet section is 1:(10-100):1, more preferably 1:(40-70).

[0036] Preferably, the ratio of the length of the larynx to the inner diameter of the larynx is 0.1-5:1, more preferably 0.5-2:1.

[0037] Preferably, in the secondary Venturi structure, the cone angle of the contraction section is 10-80°, more preferably 15-75°, and even more preferably 50-75°.

[0038] Preferably, in the secondary Venturi structure, the cone angle of the diffusion section is 10-80°, more preferably 15-75°, and even more preferably 50-75°.

[0039] The preferred secondary Venturi structure described above is beneficial for the replenishment of hydrogen-rich gas and the regulation of the overall material flow rate.

[0040] In this invention, at least one supplementary air inlet is provided at the throat of the secondary Venturi structure; preferably, 1-4 supplementary air inlets are provided at the throat of the secondary Venturi structure. Preferably, the supplementary air inlets are evenly distributed along the circumference of the throat.

[0041] According to the present invention, the activation device or activation material in the secondary Venturi structure may be the same as or different from the device or material in the primary Venturi structure, and the present invention does not have any particular limitation in this regard.

[0042] A second aspect of the present invention provides a rapid pyrolysis system for carbonaceous raw materials, the system comprising a pulverizing unit, a gasification unit, a pyrolysis unit, a dust removal unit, and a fractionation unit connected sequentially along the material flow direction; the pyrolysis unit comprises the pyrolysis reactor described in the first aspect; The pulverizing unit is used to screen carbonaceous raw materials and includes a fine particle outlet and a coarse particle outlet. The inlet of the gasification unit is connected to the fine particle outlet of the pulverizing unit and is used to gasify the screened fine particles. The dust removal unit is connected to the pyrolysis product outlet of the pyrolysis unit and is used to separate the pyrolysis products into gas and solid phases. The dust removal unit has an oil and gas outlet and a solid phase outlet. The oil and gas outlet is connected to the fractionation unit, and the solid phase outlet is connected to the inlet of the gasification unit. The fractionation unit includes at least one fractionation tower for fractionating the oil and gas from the dust removal unit. The carbonaceous raw material and booster gas inlets of the pyrolysis unit are connected to the coarse particle outlet of the pulverizing unit, the top outlet of the fractionation tower, and the gasification gas outlet of the gasification unit.

[0043] The above system further improves the oil yield and oil quality of the pyrolysis process. At the same time, it reduces the pressure of the separation unit from the reaction unit, improves the continuous stability of the device, and improves the control of temperature and flow rate of materials during the process. Furthermore, gas activation enables the controllability of the reaction field. Overall, it forms a rapid pyrolysis method and process based on multi-length coupling and regulation of the fluidized bed.

[0044] In this invention, the powder-making unit is used to screen carbonaceous raw materials, and those skilled in the art can select it according to the particle size distribution of the raw materials.

[0045] The pyrolysis reactor, as described in the first aspect, is used for the pyrolysis of carbonaceous raw materials. The primary pyrolysis products, maintained in a gas-solid state, enter a dust removal unit, which may include devices such as a cyclone separator, a filter, and a baghouse dust collector.

[0046] In this invention, after the oil and gas products undergo gas activation and oil and gas stabilization in the secondary Venturi structure of the pyrolysis reactor, it is beneficial to reduce the separation pressure of the dust removal system.

[0047] According to the present invention, preferably, the apparatus further includes a mixing and distribution device 6 for mixing the booster gas with the carbonaceous raw material and then entering the pyrolysis reactor. Specifically, the inlet of the mixing and distribution device is connected to the coarse particle outlet of the pulverizing unit, the top outlet of the fractionation tower, and the gasification gas outlet of the gasification unit, respectively, and the outlet of the carbonaceous raw material of the pyrolysis unit is connected to the booster gas inlet.

[0048] In this invention, the type and flow rate of the booster gas are related to the density and particle size of the raw materials. For example, the booster gas can be an inert atmosphere or a mixed gas containing reducing gas components. In actual industrial processes, pyrolysis gas circulation can be used for replenishment. If connected to a gasification process, it can be syngas, or some CH4 can be added to the gas. Therefore, those skilled in the art can also set other gas sources in the system as needed, and this invention does not limit this.

[0049] Preferably, the system includes a hydrogen-containing gas supply unit for providing supplemental gas.

[0050] A third aspect of the present invention provides a method for rapid pyrolysis of carbonaceous raw materials, the method being carried out in the system described in the second aspect, comprising: S1. The carbonaceous raw material is sieved to obtain particulate component I with a particle size of 0.06-0.3 mm and particulate component II with a particle size <0.06 mm; S2. Gasify the particulate component II with a particle size <0.06mm to obtain gasified gas and gasified slag; S3. In the presence of booster gas, particulate component I with a particle size of 0.06-0.3 mm is fed into the pyrolysis reactor, and supplementary gas is fed into the pyrolysis reactor through the supplementary gas inlets of the primary Venturi structure and the secondary Venturi structure to carry out the pyrolysis reaction. The booster gas is provided by at least one of gasification gas, pyrolysis gas, hydrogen-rich gas, or inert gas; S4. The pyrolysis reaction products are separated by dust removal to obtain oil and gas; S5. The oil and gas are fractionated to obtain pyrolysis gas.

[0051] The method provided by this invention has a wide range of raw material adaptability and can be applied to various carbon-containing raw materials, such as at least one of coal powder, biomass, and waste plastics, preferably coal powder.

[0052] In this invention, there are no particular limitations on the gasification conditions for step S2; conventional conditions in the art can be used, such as fluidized bed dry powder, fluidized bed coal-water slurry, or other gasification technologies. This invention does not have any special requirements in this regard. Preferably, the temperature of the gasifying gas is 500-1300℃, more preferably 650-1100℃.

[0053] The present invention allows for a wide range of temperature selection for the lifting gas. The specific temperature is determined by ensuring that the mixture provides heat to the fluidized bed pyrolyzer and guarantees the required temperature for the reaction within the pyrolyzer. Preferably, the temperature of the lifting gas is 650-1100℃, and more preferably 680-900℃.

[0054] In step S3, the amount of supplementary gas fed into the pyrolysis reactor through the primary Venturi structure can be flexibly adjusted according to different coal types. The overall calculation is based on three boundaries: fluidized transport of solid materials, guaranteed residence time, and sufficient heat supply for pyrolysis.

[0055] According to some preferred embodiments of the present invention, the carbonaceous raw material is selected from at least one of pulverized coal, biomass, and waste plastics.

[0056] Preferably, the volume ratio of the supplementary gas to the booster gas fed into the pyrolysis reactor via the primary Venturi structure is 1:(8-12).

[0057] More preferably, the volume ratio of the supplementary gas to the booster gas fed into the pyrolysis reactor via the secondary Venturi structure is 1:(10-20).

[0058] Under the above-mentioned optimal supplementary gas dosage, it is beneficial to further optimize the control depth of the coking reaction and the stability of free radicals.

[0059] Preferably, the supplementary gas is a component that can supply hydrogen, such as at least one of hydrogen, low-carbon alkanes, low-carbon alcohols, and tetrahydronaphthalene; preferably, the supplementary gas is selected from at least one of hydrogen, methanol, methane, and tetrahydronaphthalene.

[0060] Preferably, the conditions for the pyrolysis reaction include: a temperature of 500-750℃, more preferably 520-620℃, a pressure of 0.1-7MPa, more preferably 2-3MPa, and a residence time of 3-10s for the carbonaceous raw material, more preferably 5-9s.

[0061] In this invention, "residence time of carbonaceous raw material" refers to the total time from when the carbonaceous raw material enters the pyrolysis reactor to when it leaves the pyrolysis reactor. In this invention, the gas velocity of the booster gas is controlled to maintain the raw material in a fluidized state, and the above residence time is satisfied during continuous feeding and discharging.

[0062] Under the above-mentioned preferred embodiments, it is beneficial to improve oil yield and tar stability.

[0063] The present invention will be described in detail below through embodiments.

[0064] Example 1 Adopting such Figure 2 The rapid pyrolysis system shown includes a pulverizing unit 1, a gasification unit 5, a pyrolysis unit 2, a dust removal unit 3, and a fractionation unit 4 connected sequentially along the material flow direction; the pyrolysis unit includes, as shown in the figure... Figure 1 The pyrolysis reactor shown is Figure 1 As shown, the pyrolysis reactor includes a vertically arranged activation reaction section and a horizontally arranged activation stabilization section, which are connected by a bent pipe. The activation reaction section has a height of 4.2m and the activation stabilization section has a length of 0.5m. From bottom to top, the activation reaction section includes a mixing zone and a reaction lifting zone with heights of 0.6m and 3.6m, respectively. The equal-diameter section, the reduced-diameter section, and the narrow-diameter section of the reaction lifting zone have heights of 2.8m, 0.2m, and 0.6m, respectively, and the inner diameter of the narrow-diameter section is 30mm and the inner diameter of the equal-diameter section is 40mm.

[0065] The mixing zone contains a primary Venturi structure with a throat having an inner diameter of 20 mm and a length of 20 mm. The inlet section has an inner diameter of 40 mm, and both the contraction and diffusion sections have a cone angle of approximately 75°. Four supplementary gas inlets are evenly distributed circumferentially within the throat of the primary Venturi structure. The activation and stabilization zone contains a secondary Venturi structure with a throat having an inner diameter of 16 mm and a length of 16 mm. The inlet section has an inner diameter of 30 mm, and both the contraction and diffusion sections have a cone angle of 75°. Four supplementary gas inlets are also evenly distributed circumferentially within the throat of the secondary Venturi structure. Each supplementary gas inlet is equipped with an activation material (silicon carbide on the outer surface and FeNi alloy on the inner surface).

[0066] The above system was used for rapid pyrolysis. The carbonaceous raw material used was a low-rank coal from northern Shanxi. The coal powder was screened in the pulverizing unit to obtain particle component I with a particle size of 0.06-0.3 mm and particle component II with a particle size <0.06 mm. Particle component II with a particle size <0.06 mm was gasified in an entrained flow bed (1350℃) to obtain gasification gas (~1300℃) and gasification slag. Particle component I (80 g / min) with a particle size of 0.06-0.3 mm was fed into the pyrolysis reactor using booster gas (temperature adjusted to ~750℃, 50 L / min). Hydrogen-containing gas with a hydrogen content of 25 vol% was fed into the pyrolysis reactor through the supplementary gas inlets of the primary and secondary Venturi structures for pyrolysis reaction. The booster gas was provided by gasification gas and pyrolysis gas. The supplementary gas flow rate into the pyrolysis reactor through the primary Venturi structure was 5 L / min, and the flow rate into the pyrolysis reactor through the secondary Venturi structure was 3 L / min. The reaction conditions in the pyrolysis reactor were: temperature 520℃, pressure 2.1 MPa, and residence time of carbonaceous feedstock 5.5 s.

[0067] The pyrolysis reaction products are separated by dust removal to obtain oil and gas; the oil and gas are then fractionated to obtain pyrolysis gas and tar.

[0068] The calculated oil yield is 14.5% (the gold value of this coal type is 9.35%, and the calculated oil yield is ≥ 155% of the gold value), and the content of heavy components in the oil is reduced to below 27% (the proportion of fractions above 420℃ in the total tar), with an overall ideal effect.

[0069] Wherein, oil yield (%) = oil mass / coal powder feed rate × 100%.

[0070] Example 2 The difference is that, following the method in Implementation 1, no supplementary gas enters the secondary Venturi structure.

[0071] The calculated oil yield was 14.2%, and the content of heavy components in the oil was 42%. Compared with Example 1, the oil yield was not significantly different, but the overall oil was heavier and the oil stability was slightly worse.

[0072] Example 3 The method is the same as in Example 1, except that no supplementary gas is introduced into the primary venturi structure, and the temperature of the boosting gas is approximately 800°C.

[0073] The yield of low-rank kerosene from northern Shanxi was 13.7%, and the content of heavy components in the oil was 29%, with a reduction in the heavy component, but the oil yield decreased significantly.

[0074] Example 4 The method is the same as in Example 1, except that the structure of the pyrolysis reactor is different: the narrow diameter section and the constricted diameter section in the pyrolysis reactor are relatively long, with the constant diameter section being 1.4 m, the constricted diameter section being 1.1 m, and the narrow diameter section being 1.1 m.

[0075] The yield of low-rank kerosene from northern Shanxi was 13.4%, and the content of heavy components in the oil was 31%.

[0076] Comparative Example 1 The method is the same as in Example 1, except that the primary venturi structure is replaced with a tube of equal diameter of the same height.

[0077] The yield of low-rank kerosene from northern Shanxi was 13.7%, and the oil yield decreased when the content of heavy components in the oil was 36%.

[0078] Comparative Example 2 The method is the same as in Example 1, except that the secondary Venturi structure is replaced with a tube of equal diameter at the same height.

[0079] The yield of low-rank kerosene from northern Shanxi was 13.5%, and the oil yield did not decrease significantly with a heavy component content of 44%, but the degree of heavy component content in the oil increased.

[0080] The results above show that the embodiments using the multi-field enhancement auxiliary methods proposed in this invention have higher oil yield and better oil quality.

[0081] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A pyrolysis reactor, characterized in that, The pyrolysis reactor includes a vertically arranged activation reaction section and a horizontally arranged activation stabilization section, which are connected in series along the material flow direction. From bottom to top, the activation reaction section includes a mixing zone and a reaction enhancement zone; wherein, the mixing zone contains a first-order Venturi structure, and the activation stabilization section contains a second-order Venturi structure; At least one supplementary gas inlet is provided at the throat of both the primary and secondary Venturi structures. The supplementary gas inlet is equipped with an activation device and / or activation material for activating the supplementary gas. The inlet section of the primary Venturi structure is equipped with a carbonaceous raw material and a booster gas inlet, and the outlet section of the secondary Venturi structure is equipped with a pyrolysis product outlet.

2. The pyrolysis reactor according to claim 1, characterized in that, The activation reaction section and the activation stabilization section are connected by a bent pipe or a right-angle pipe; The length ratio of the activation reaction section to the activation stabilization section is 1:0.001-0.2; In the activation reaction section, the height of the reaction enhancement zone accounts for 60-90% of the total height of the activation reaction section.

3. The pyrolysis reactor according to claim 1 or 2, characterized in that, From bottom to top, the reaction enhancement zone includes a constant diameter section, a reduced diameter section, and a narrow diameter section, wherein the inner diameter of the constant diameter section is the same as the inner diameter at the outlet of the outlet section of the first-stage Venturi structure. The ratio of the inner diameter of the equal diameter section to that of the narrow diameter section is 1:(0.1-1). The height ratio of the equal diameter section, the reduced diameter section, and the narrow diameter section is 1:0.01-1:0.01-1.

4. The pyrolysis reactor according to claim 1 or 2, characterized in that, The first-order Venturi structure includes an inlet section, a constriction section, a throat, and a diffusion section; In a first-order Venturi structure, the ratio of the inner diameter of the throat to the inner diameter at the entrance of the inlet segment is 1:(10-100); and / or, the ratio of the axial length of the throat to the inner diameter of the throat is 0.1-5:

1. In a first-order Venturi structure, the cone angle of the contraction section is 10-80° when calculated based on acute angles; and / or, the cone angle of the diffusion section is 10-80°. One to four hydrogen-rich gas inlets are evenly distributed circumferentially at the throat of the primary Venturi structure. The activation device is an internal electrode and / or a plasma device; The activating material is plasma and / or an activation catalyst.

5. The pyrolysis reactor according to claim 1 or 2, characterized in that, The secondary Venturi structure includes an inlet section, a constriction section, a throat, and a diffusion section; In a second-order Venturi structure, the ratio of the inner diameter of the throat to the inner diameter at the entrance of the inlet segment is 1:(10-100); and / or, the ratio of the axial length of the throat to the inner diameter of the throat is 0.1-5:

1. In a second-order Venturi structure, the cone angle of the contraction section is 10-80° when calculated based on acute angles; and / or, the cone angle of the diffusion section is 10-80° when calculated based on acute angles. One to four hydrogen-rich gas inlets are evenly distributed circumferentially at the throat of the secondary Venturi structure.

6. A rapid pyrolysis system for carbonaceous raw materials, characterized in that, The system includes a pulverizing unit, a gasification unit, a pyrolysis unit, a dust removal unit, and a fractionation unit connected sequentially along the material flow direction; the pyrolysis unit includes the pyrolysis reactor as described in any one of claims 1-5; The pulverizing unit is used to screen carbonaceous raw materials and includes a fine particle outlet and a coarse particle outlet. The inlet of the gasification unit is connected to the fine particle outlet of the pulverizing unit and is used to gasify the screened fine particles. The dust removal unit is connected to the pyrolysis product outlet of the pyrolysis unit and is used to separate the pyrolysis products into gas and solid phases. The dust removal unit has an oil and gas outlet and a solid phase outlet. The oil and gas outlet is connected to the fractionation unit, and the solid phase outlet is connected to the inlet of the gasification unit. The fractionation unit includes at least one fractionation tower for fractionating the oil and gas from the dust removal unit. The carbonaceous raw material and booster gas inlets of the pyrolysis unit are connected to the coarse particle outlet of the pulverizing unit, the top outlet of the fractionation tower, and the gasification gas outlet of the gasification unit.

7. The system according to claim 6, characterized in that, The dust removal unit includes at least one of a cyclone separator, a filter, and a bag filter. The device also includes a gas mixing and distribution device, the inlet of which is connected to the coarse particle outlet of the pulverizing unit, the top outlet of the fractionation tower, and the gasification gas outlet of the gasification unit, and the outlet of the carbonaceous raw material and the lifting gas inlet of the pyrolysis unit.

8. A method for rapid pyrolysis of carbonaceous raw materials, characterized in that, The method is performed in the system described in claim 6 or 7, and includes: S1. The carbonaceous raw material is sieved to obtain particulate component I with a particle size of 0.06-0.3 mm and particulate component II with a particle size <0.06 mm; S2. Gasify the particulate component II with a particle size <0.06mm to obtain gasified gas and gasified slag; S3. In the presence of booster gas, particulate component I with a particle size of 0.06-0.3 mm is fed into the pyrolysis reactor, and supplementary gas is fed into the pyrolysis reactor through the supplementary gas inlets of the primary Venturi structure and the secondary Venturi structure to carry out the pyrolysis reaction. The booster gas is provided by at least one of the following: gasification gas, pyrolysis gas, hydrogen-rich gas, and inert gas; S4. The pyrolysis reaction products are separated by dust removal to obtain oil and gas; S5. The oil and gas are fractionated to obtain pyrolysis gas and tar.

9. The method according to claim 8, characterized in that, The carbonaceous raw material is selected from at least one of pulverized coal, biomass, and waste plastics; In step S2, the temperature of the vaporized gas is 500-1300℃; The temperature of the booster gas is 650-1100℃.

10. The method according to claim 8 or 9, characterized in that, The volume ratio of the supplementary gas to the booster gas fed into the pyrolysis reactor via the primary Venturi structure is 1:(8-12). The volume ratio of the supplementary gas to the booster gas fed into the pyrolysis reactor via the secondary Venturi structure is 1:(10-20).

11. The method according to claim 8 or 9, characterized in that, The supplementary gas is a component that can supply hydrogen, selected from at least one of hydrogen, low-carbon alkanes, low-carbon alcohols and tetrahydronaphthalene; The conditions for the pyrolysis reaction include: a temperature of 500-750℃, a pressure of 0.1-7MPa, and a residence time of 3-10s for the carbonaceous raw material.

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