A biomass pyrolysis process and equipment

Abstract

The present invention discloses a biomass pyrolysis process, the steps of which include putting biomass raw materials and catalysts into a gasifier for pyrolysis and gasification, thereby obtaining combustible gas and solid particles; and then collecting the combustible gas and solid particles respectively. The present invention also discloses a biomass pyrolysis device, which includes a gasifier, and the gasifier includes a furnace body and a cover body from top to bottom; the lower end of the furnace body is open and a furnace screen is provided at the open part, a stirring shaft coaxial with the furnace body is vertically provided in the furnace body, a pulling rod is provided on the side wall of the stirring shaft, and the stirring shaft is connected to the stirring motor by transmission; a vertical shaft is also provided in the furnace body, and stirring rods are arranged in an array along the vertical direction on the side wall of the vertical shaft, and a communicating flow channel is provided in the vertical shaft and the stirring rod, and the opening of the flow channel at the upper end of the vertical shaft is connected to one end of a circulating water pipe. The purpose of the present invention is to flexibly adjust the temperature in the gasifier, thereby adjusting the proportion of the product.

Description

Technical Field

[0001] The present invention relates to the field of biomass utilization, and in particular to a biomass pyrolysis process and equipment. Background Art

[0002] Biomass primarily refers to organic materials such as straw and wood chips. To utilize biomass materials like straw generated during daily labor, they are typically fed into a gasifier for pyrolysis to produce combustible gas, which can be used as a clean energy source. The activated carbon produced after pyrolysis is then used as a soil conditioner or air purifier.

[0003] However, due to the limited availability of biomass raw materials and unstable raw material sources (for example, raw materials are abundant during harvest time but less available at other times), biomass utilization is not ideal. Currently, centralized industrial processing is often used to address the poor performance of decentralized utilization. Centralizing biomass fuel processing can address the problems of raw material shortages and lack of professional maintenance that often arise in decentralized processing.

[0004] To pyrolyze biomass feedstock, the process involves feeding it into a gasifier. However, the ratio of activated carbon to combustible gas varies depending on the temperature. To meet market demand, the gasifier temperature needs to be flexibly adjusted. Summary of the Invention

[0005] The purpose of the present invention is to address the above problems and provide a biomass pyrolysis process and equipment that can flexibly adjust the temperature in the gasifier, thereby adjusting the ratio of activated carbon and combustible gas in the product.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is a biomass pyrolysis process: biomass raw materials and catalysts are put into a gasifier for pyrolysis and gasification to obtain combustible gas and solid particles; the combustible gas and solid particles are then collected separately. Under the action of the catalyst, the biomass raw materials in the gasifier are divided into a drying zone, a pyrolysis zone, an oxidation zone, a reduction zone and a cooling zone from top to bottom. The temperature of the drying zone is controlled at 100-250°C, the pyrolysis zone is in an oxygen-deficient environment and the temperature is controlled at 550-650°C, the oxidation zone is in an oxygen-deficient environment and the temperature is controlled at 650-800°C, and the reduction zone is in an oxygen-deficient environment and the temperature is controlled at 650-850°C; under the action of thermal decomposition, the biomass releases a large amount of biomass combustible gas such as carbon dioxide, carbon monoxide, hydrogen, methane, and solid particles such as activated carbon. The redox layer is the main reaction area of ​​biomass gasification.

[0007] The present invention also discloses a biomass pyrolysis device, which is used in the biomass pyrolysis process of Example 1, and includes a gasifier, which includes a furnace body and a cover body from top to bottom, a feed port is provided at the upper end of the furnace body, and biomass raw materials enter the furnace body from the feed port, and the biomass raw materials are mixed with a catalyst and then undergo a pyrolysis reaction in the furnace body; the lower end of the furnace body is open and a furnace screen is provided at the open part, the lower part of the furnace body extends into the cover body from the upper end of the cover body, an outlet pipe as a combustible gas outlet is provided on the cover body, and a vent pipe is provided at the lower end of the cover body. Coal outlet; a stirring shaft coaxial with the furnace body is vertically arranged, a pulling rod is arranged on the side wall of the stirring shaft, the pulling rod is arranged horizontally, and the stirring shaft is connected to the stirring motor; a vertical shaft is also provided in the furnace body, and stirring rods are arranged in an array along the vertical direction on the side wall of the vertical shaft, and the stirring rods are positioned in the oxidation zone, reduction zone and cooling zone, and a connecting flow channel is provided in the vertical shaft and the stirring rod, the flow channel is connected to one end of a circulating water pipe at an opening at the upper end of the vertical shaft, and the other end of the circulating water pipe extends out of the furnace body and is connected to a water source.

[0008] Furthermore, in order to ensure that solid particles such as activated carbon can fall off the furnace screen, a feed hole is provided in the middle of the furnace screen, and the upper end surface of the furnace screen is provided as an inclined surface that slopes downward toward one side of the feed hole.

[0009] Furthermore, in order to ensure that solid particles such as activated carbon can fall off the furnace screen, a circle of transmission teeth concentric with it is provided on the furnace screen, and the transmission teeth are engaged with the driving gear. The driving gear is provided on the output shaft of the furnace screen drive motor. The vibration generated by the rotation of the furnace screen causes the solid particles to fall.

[0010] Furthermore, in order to avoid clogging of the sieve holes on the furnace screen, the furnace screen includes a furnace screen plate and a support spaced apart from top to bottom, a spring is provided between the furnace screen plate and the support, and the support is provided with an interpenetrating portion that is adapted to the number and position of the sieve holes on the furnace screen plate, and the upper end surface of the interpenetrating portion extends out of the upper end surface of the furnace screen plate. As the furnace screen rotates and the interpenetrating portion contacts the material, the interpenetrating portion swings in the sieve holes, so that the material will not clog the sieve holes, and the upper part of the interpenetrating portion has an arc.

[0011] Furthermore, in order to prevent the spring from getting stuck, the spring is arranged in the telescopic tube.

[0012] Furthermore, in order to flexibly adjust the stability of each zone and to make the lower end surface of the lowest stirring rod lower than the upper end surface of the interpenetrating part, a lifting column is provided in the gasification furnace, and a lifting drive device is provided in the lifting column for driving the vertical axis to move in the vertical direction.

[0013] Furthermore, to prevent materials from getting stuck in the vertical shaft, a receiving groove is provided at the lower end of the vertical shaft, the upper end of the jacking column is inserted into the receiving groove, and the piston rod of the jacking drive device passes through the upper end surface of the jacking column and is connected to the top wall of the receiving groove.

[0014] Furthermore, in order to make the material fall out of the cover instead of staying at the bottom of the cover, the carbon outlet is set on one side of the cover axis, and a carbon pulling scraper is set on the bottom wall of the cover. The carbon pulling scraper is set on the output shaft of the scraper drive motor.

[0015] Furthermore, in order to level and compact the material, the lower end of the puller rod is connected to the pressing plate through a connecting rod.

[0016] The beneficial effects of the present invention are as follows: the circulating water pipe delivers the liquid into the vertical shaft and the stirring rod. By adjusting the temperature of the liquid entering the vertical shaft and the stirring rod, the temperature in the gasification furnace can be flexibly adjusted; at the same time, during the rotation of the furnace screen, the stirring rod and the material produce relative movement, so that the material can fall from the furnace screen into the cover more smoothly.

[0017] 1. The furnace screen consists of a furnace screen plate and upper and lower intervals of the support, which are connected by a spring. When the furnace screen rotates, the object drives the interpenetrating part on the support to shake or move up and down to prevent the material from being stuck in the sieve holes on the furnace screen plate.

[0018] 2. The vertical shaft rises and falls under the drive of the jacking drive device in the jacking column, thereby adjusting the position of the stirring rod in the furnace body along the vertical direction to flexibly adjust the temperature of the pyrolysis zone, oxidation zone and reduction zone. When the lowest stirring rod is at the lowest position it can reach, it can contact the upper part of the interpenetrating part, thereby driving the interpenetrating part to move downward to further prevent the sieve holes from being blocked.

[0019] 3. Equipped with pulling rods and pressing plates, they can level and compact the biomass raw materials entering the furnace body. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the internal structure of the present invention.

[0021] Figure 2 for Figure 1 A is a partial enlarged schematic diagram of the figure.

[0022] Figure 3 The schematic diagram of the connection between the puller rod and the pressure plate is in the radial direction of the puller rod.

[0023] The text labels in the figure are as follows: 1. furnace body; 2. cover body; 3. feed port; 4. furnace screen; 401. furnace screen plate; 402. support; 403. spring; 404. insertion part; 405. telescopic tube; 5. air outlet pipe; 6. charcoal outlet; 7. stirring shaft; 8. pulling rod; 9. stirring motor; 10. vertical shaft; 11. stirring rod; 12. circulating water pipe; 13. discharge hole; 14. transmission tooth; 15. driving gear; 16. furnace screen drive motor; 17. lifting column; 18. storage trough; 19. charcoal pulling scraper; 20. scraper drive motor; 21. connecting rod; 22. pressing plate. DETAILED DESCRIPTION

[0024] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is described in detail below with reference to the accompanying drawings. The description in this part is only exemplary and explanatory and should not have any limiting effect on the scope of protection of the present invention.

[0025] Example 1: A biomass pyrolysis process, which includes the following steps: putting biomass raw materials and catalysts into a gasifier for pyrolysis and gasification to obtain combustible gas and solid particles; then collecting the combustible gas and solid particles separately; under the action of the catalyst, the biomass raw materials in the gasifier are divided into a drying zone, a pyrolysis zone, an oxidation zone, a reduction zone and a cooling zone from top to bottom, wherein the temperature of the drying zone is controlled at 100-250°C, the pyrolysis zone is in an oxygen-deficient environment and the temperature is controlled at 550-650°C, the oxidation zone is in an oxygen-deficient environment and the temperature is controlled at 650-800°C, and the reduction zone is in an oxygen-deficient environment and the temperature is controlled at 650-850°C; wherein the oxidation zone and the reduction zone are the main reaction areas of biomass gasification, and the cellulose in the biomass releases a large amount of biomass combustible gas such as carbon dioxide, carbon monoxide, hydrogen, and methane under the action of thermal decomposition, and the other parts generate activated carbon, etc.

[0026] Example 2: A biomass pyrolysis device, which can be used for the pyrolysis gasification in Example 1, can also be used for other biomass pyrolysis processes, such as Figure 1-3As shown, it includes a gasifier, which includes a furnace body 1 and a cover body 2 from top to bottom. The outer diameter of the furnace body 1 is smaller than the inner diameter of the cover body 2. The upper end of the furnace body 1 is provided with a feed port 3; the lower end of the furnace body 1 is open and a furnace screen 4 is provided at the open part, and the furnace screen 4 closes the open part of the lower end of the furnace body 1. The lower part of the furnace body 1 extends into the cover body 2 from the upper end of the cover body 2. The connection between the furnace body 1 and the cover body 2 is sealed by welding or the like. The upper part of the side wall of the cover body 2 is provided with an outlet pipe 5 as a combustible gas outlet, and the lower end of the cover body 2 is provided with a charcoal outlet 6; a stirring shaft 7 coaxial with the furnace body 1 is vertically provided in the furnace body 1, and the stirring shaft 7 is a hollow tube. A pulling rod 8 is provided on the side wall of the stirring shaft 7. 8 is arranged horizontally, and the upper end of the stirring shaft 7 passes through the bearing on the top wall of the furnace body 1 and is connected to the stirring motor 9 at the upper end of the furnace body 1; a vertical shaft 10 is also provided in the furnace body 1, and the vertical shaft 10 is coaxially arranged with the stirring shaft, and stirring rods 11 are arranged in an array along the vertical direction on the side wall of the vertical shaft 10, and a connecting flow channel is provided in the vertical shaft 10 and the stirring rod 11, and the opening of the flow channel at the upper end of the vertical shaft 10 is connected to one end of the circulating water pipe 12, and the circulating water pipe 12 passes through the stirring shaft 7, and the other end of the circulating water pipe 12 extends out of the furnace body 1 and is connected to the water source; the lower end of the pulling rod 8 is connected to the pressure plate 22 through the connecting rod 21, and the pressure plate 22 extends obliquely upward at the front end in the rotation direction of the stirring shaft.

[0027] Specific working status: biomass raw materials are added to the furnace body 1, and the pulling rod 8 flattens and compacts the biomass raw materials. The biomass raw materials can be divided into a drying zone, a pyrolysis zone, an oxidation zone, a reduction zone and a cooling zone from top to bottom; under the action of the air catalyst, a large amount of combustible gas is generated, and the solid part of the biomass after the reaction is completed generates activated carbon, etc. The stirring rod 11 is located in the pyrolysis layer, the redox layer and the cooling zone. According to the ratio of the required products, the temperature of the liquid entering the circulating water pipe 12 is adjusted to achieve effective control of the oxidation and reduction reaction process, and finally obtain biochar and combustible gas; the generated biochar falls into the lower end of the cover.

[0028] Example 3, as Figure 1 As shown, the other structures of this embodiment are the same as those of Example 2, but in this embodiment, a jacking column 17 is provided in the gasifier, and the jacking column 17 has a heat insulation effect. The lower end of the jacking column 17 passes through the furnace screen 4 and is connected to the support part in the cover body 2, and the two ends of the support part are fixed on the inner wall of the cover body 2. A jacking drive device for driving the vertical shaft 10 to move in the vertical direction is provided in the jacking column 17. The jacking drive device can adopt an oil cylinder. A discharge hole 13 is provided in the middle of the furnace screen 4, and the upper end face of the furnace screen 4 is provided as an inclined surface inclined downward to one side of the discharge hole 13; a circle of transmission teeth 14 concentric with it is provided on the furnace screen 4, and the transmission teeth 14 are meshed with the driving gear 15. The driving gear 15 is provided on the output shaft of the furnace screen drive motor 16, and the furnace screen drive motor 16 is provided on the outside of the cover body 2.

[0029] The specific working state is the same as that of Example 2, but in this embodiment, the furnace screen 4 rotates under the drive of the furnace screen drive motor 16, so that the activated carbon and the like can fall into the cover body 2 more smoothly. At the same time, in order to install the lifting column and the vertical shaft 10, a support part is set in the cover body 2.

[0030] Example 3, as Figure 1-2 As shown, the other structures of this embodiment are the same as those of embodiment 3, but in this embodiment, the furnace screen 4 includes a furnace screen plate 401 and a support 402 spaced apart from each other from top to bottom, the outer wall of the furnace screen plate 401 extends into the groove of the side wall of the furnace body 1 and is connected to the bearing in the groove, the sieve hole is provided on the furnace screen plate 401, the transmission gear 14 is provided at the lower end of the furnace screen plate 401, a spring 403 is provided between the furnace screen plate 401 and the support 402, and the spring 403 is provided on the telescopic tube 40 5, the telescopic tube 405 is composed of two nested sleeves, wherein the upper sleeve with a larger diameter is located at the top, the upper end of the upper sleeve is fixed to the lower end of the furnace sieve plate 401, and the lower end of the lower sleeve is fixed to the upper end of the support 402. The cross section of the support 402 is circular, and the support 402 is provided with an insertion portion 404 that is compatible with the number and position of the sieve holes on the furnace sieve plate 401. The upper end surface of the insertion portion 404 extends out of the upper end surface of the furnace sieve plate 401. The insertion portion 404 is preferably a cone that is narrow at the top and wide at the bottom.

[0031] The specific working state is the same as that of Example 3, but in this embodiment, the jacking drive device pulls the vertical shaft 10 to the lowest end it can reach. At this time, the stirring rod 11 at the lowest end of the vertical shaft contacts the upper part of the insertion part 404. As the furnace screen 4 rotates, the insertion part 404 shakes under the action of the cooling layer material, the stirring rod 11 and the spring 403, thereby preventing the material from being stuck in the screen hole.

[0032] Example 4, as Figure 1 As shown, the other structures of this embodiment are the same as those of Example 3, but in this embodiment, a receiving groove 18 is provided at the lower end of the vertical shaft, the upper end of the jacking column 17 is inserted into the receiving groove 18, and the piston rod of the jacking drive device passes through the upper end surface of the jacking column 17 and is connected to the top wall of the receiving groove 18; thereby preventing materials from entering between the vertical shaft 10 and the jacking column 17.

[0033] Example 5, as Figure 1 As shown, the other structures of this embodiment are the same as those of Example 2, but in this embodiment, the carbon outlet 6 is arranged on one side of the axis of the cover body 2, and a carbon extraction scraper 19 is provided on the bottom wall of the cover body 2. The length of the carbon extraction scraper 19 is adapted to the radius of the bottom wall of the cover body 2; the carbon extraction scraper 19 is provided on the output shaft of the scraper drive motor 20, and the output shaft of the scraper drive motor 20 is coaxially arranged with the cover body 2. The output shaft of the scraper drive motor 20 passes through the sealed bearing in the bottom wall of the cover body 2 and is connected to the carbon extraction scraper 19; as the carbon extraction scraper 19 rotates, the material is pushed toward the carbon outlet 6.

[0034] It should be noted that, in this article, the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements that are inherent to such process, method, article or apparatus.

[0035] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. The above is only a preferred implementation method of the present invention. It should be pointed out that due to the limitations of textual expression, there are objectively infinite specific structures. For ordinary technicians in this technical field, without departing from the principles of the present invention, they can make several improvements, modifications or changes, and can also combine the above technical features in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the inventive concept and technical solution to other occasions without improvement, should be regarded as the scope of protection of the present invention.

Claims

1. A biomass pyrolysis device, comprising a gasifier, the gasifier comprising a furnace body (1) and a cover body (2) from top to bottom, the furnace body (1) having an upper end provided with a feed port (3); the furnace body (1) having an open lower end and a furnace screen (4) provided at the open portion, the furnace body (1) having a lower portion extending from the upper end of the cover body (2) into the cover body (2), the cover body (2) having an outlet pipe (5) as a combustible gas outlet, the cover body (2) having a lower end provided with a charcoal outlet (6), characterized in that: A stirring shaft (7) coaxial with the stirring shaft (7) is vertically arranged in the furnace body (1), a pulling rod (8) is arranged on the side wall of the stirring shaft (7), the pulling rod (8) is arranged horizontally, and the stirring shaft (7) is connected to the stirring motor (9) in a transmission manner; a vertical shaft (10) is also arranged in the furnace body (1), and stirring rods (11) are arranged in an array along the vertical direction on the side wall of the vertical shaft (10), and a communicating flow channel is arranged in the vertical shaft (10) and the stirring rods (11), and the opening of the flow channel at the upper end of the vertical shaft (10) is connected to one end of a circulating water pipe (12), the circulating water pipe (12) passes through the stirring shaft (7), and the other end of the circulating water pipe (12) extends out of the furnace body (1) and is connected to a water source; a circle of transmission teeth (14) coaxial with the stirring shaft (7) is arranged on the furnace screen (4), and the transmission teeth (14) mesh with a driving gear (15), and the driving gear (15) is arranged at the output of the furnace screen drive motor (16). The furnace screen (4) comprises a furnace screen plate (401) and a support (402) which are spaced apart from each other from top to bottom, a spring (403) is arranged between the furnace screen plate (401) and the support (402), and an insertion portion (404) which matches the number and position of the sieve holes on the furnace screen plate (401) is arranged on the support (402), and the upper end surface of the insertion portion (404) protrudes from the upper end surface of the furnace screen plate (401); a lifting device is arranged in the gasifier. A column (17) is provided with a lifting drive device for driving the vertical shaft (10) to move in the vertical direction. The lower end of the lifting column (17) passes through the furnace screen (4) and is connected to the support part in the cover body (2). The two ends of the support part are fixed on the inner wall of the cover body (2). When the stirring rod (11) of the lowest layer is at the lowest position it can reach, it can contact the upper part of the insertion part (404), thereby driving the insertion part (404) to move downward.

2. A biomass pyrolysis device according to claim 1, characterized in that: A material discharge hole (13) is provided in the middle of the furnace screen (4), and an upper end surface of the furnace screen (4) is provided as an inclined surface that slopes downward toward one side of the material discharge hole (13).

3. The biomass pyrolysis equipment according to claim 1, characterized in that: The spring (403) is arranged in the telescopic tube (405).

4. The biomass pyrolysis equipment according to claim 1, characterized in that: A receiving groove (18) is provided at the lower end of the vertical shaft, the upper end of the jacking column (17) is inserted into the receiving groove (18), and the piston rod of the jacking drive device passes through the upper end surface of the jacking column (17) and is connected to the top wall of the receiving groove (18).

5. The biomass pyrolysis equipment according to claim 1, characterized in that: The charcoal outlet (6) is arranged on one side of the axis of the cover body (2), and a charcoal extraction scraper (19) is arranged on the bottom wall of the cover body (2), and the charcoal extraction scraper (19) is arranged on the output shaft of the scraper drive motor (20).

6. The biomass pyrolysis equipment according to claim 1, characterized in that: The lower end of the pulling rod (8) is connected to the pressing plate (22) via a connecting rod (21).

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