Bamboo waste pyrolysis poly-generation device and process

Abstract

The invention provides a bamboo waste pyrolysis poly-generation device and process, relates to the field of organic solid waste reutilization, and aims to solve the problem of low pyrolysis efficiency caused by poor pyrolysis continuity and stability of bamboo processing waste at present, a two-stage pyrolysis furnace structure is adopted, bamboo waste is preliminarily pyrolyzed in a first pyrolysis furnace, a product enters a second pyrolysis furnace to be deeply pyrolyzed, and the pyrolysis efficiency is improved. Sufficient pyrolysis of materials is ensured, and the product quality is optimized; pyrolysis gas produced by the two pyrolyzing furnaces is guided into the incinerator to be combusted to generate high-temperature flue gas, one part of the pyrolysis gas is supplied with heat according to the sequence from the second pyrolyzing furnace to the first pyrolyzing furnace, the combustion pyrolysis gas is utilized for self-supply heat supply, dependence on external energy is reduced, meanwhile, sufficient pyrolysis gas is produced by the two pyrolyzing furnaces, stable heat supply is maintained, heat supply is prevented from being affected by insufficient pyrolysis gas, and the service life of the pyrolyzing furnace is prolonged. By means of stable pyrolysis gas output and heat supply, abnormal fluctuation of pyrolysis can be reduced, the possibility of rapid or non-uniform generation of tar is reduced, and frequent shutdown can be avoided by means of the continuous and stable pyrolysis process.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of organic solid waste recycling, in particular to a bamboo waste pyrolysis multi-production device and process. BACKGROUND

[0002] The waste such as bamboo chips and bamboo edge scraps generated in the process of bamboo processing and after use are usually disposed by direct incineration or landfill, or are used to produce bamboo charcoal, prepare bamboo pulp, process composite boards, and extract bamboo vinegar. Pyrolysis is an effective means for high-value utilization of organic solid waste, which can convert bamboo processing waste into high-value products such as biochar and biofuel gas.

[0003] The moisture content of bamboo processing waste is high and fluctuates greatly, usually reaching 30-42%, which causes the failure rate of the crushing equipment to increase. The existing method of organic waste pyrolysis multi-production converts bamboo processing waste into pyrolysis raw materials from the beginning of bamboo fragment and wire drawing, realizing energy cascade utilization. However, in the process of pyrolysis of bamboo processing waste, a single pyrolysis furnace is prone to insufficient pyrolysis and unstable product quality (such as biochar and pyrolysis oil). However, by adding a pyrolysis furnace, the dependence on external energy is higher due to the need for continuous heating during pyrolysis. In addition, the pyrolysis gas containing combustible components produced by a single pyrolysis furnace is difficult to meet the heating demand due to insufficient pyrolysis, and the produced tar is prone to adhere to the furnace wall, causing the equipment to need frequent shutdown for decoking. The continuity of pyrolysis gas production is poor, resulting in poor stability of the heating of the pyrolysis furnace, affecting the pyrolysis efficiency and reducing the service life of the equipment. SUMMARY

[0004] The present application aims to overcome the defects of the prior art and provide a bamboo waste pyrolysis multi-production device and process. The device adopts a two-stage pyrolysis furnace structure, the bamboo waste is preliminarily pyrolyzed in the first pyrolysis furnace, and the product is further pyrolyzed in the second pyrolysis furnace to ensure sufficient pyrolysis of the material and optimize the product quality. The pyrolysis gas produced by the two pyrolysis furnaces is introduced into the incinerator to produce high-temperature flue gas, a part of which is used for heating in the order of the second pyrolysis furnace to the first pyrolysis furnace, utilizing the self-supply of combustion pyrolysis gas to reduce the dependence on external energy.

[0005] The first object of the present application is to provide a bamboo waste pyrolysis multi-production device, which adopts the following scheme: It comprises: a feeding assembly comprising a drying device and a temporary storage bin, the drying device being connected to the temporary storage bin; a pyrolysis assembly comprising a first pyrolysis furnace and a second pyrolysis furnace, the feeding port of the first pyrolysis furnace being connected to the temporary storage bin, the discharging port of the first pyrolysis furnace being connected to the feeding port of the second pyrolysis furnace, and the discharging port of the second pyrolysis furnace being connected to a multi-stage cooling screw; The heat supply assembly comprises a burning furnace and a steam boiler, the pyrolysis gas outlets of the first pyrolysis furnace and the second pyrolysis furnace are connected to the burning furnace respectively, the high-temperature flue gas of the burning furnace is connected to the second pyrolysis furnace and the first pyrolysis furnace in turn in one way, and connected to the steam boiler in another way, and the steam output by the steam boiler or the high-temperature flue gas discharged from the first pyrolysis furnace is connected to the drying equipment to utilize the waste heat.

[0006] Further, the high-temperature flue gas output by the first pyrolysis furnace is also connected to the steam boiler, and the other way of the high-temperature flue gas output by the mixed burning furnace is jointly connected to the steam boiler.

[0007] Further, the first pyrolysis furnace and the second pyrolysis furnace each comprise a cylindrical pyrolysis furnace body, a spiral flue gas chamber and a heat preservation layer are sequentially sleeved outside the pyrolysis furnace body, the flue gas chamber is used for flue gas circulation; a rotating shaft, a support and a scraper are arranged inside the pyrolysis furnace body, the rotating shaft is coaxially distributed with the pyrolysis furnace body, the support is distributed in a spiral line shape around the rotating shaft at intervals, one end of the support is connected to the rotating shaft, and the other end extends to the inner wall of the pyrolysis furnace body and is connected to the scraper.

[0008] Further, the support is a support rod and is arranged radially along the rotating shaft, and the scraper is distributed in an inclined manner relative to the axis of the support rod and is movably connected to the support rod through a pin shaft.

[0009] Further, the support is a spiral fin, the inner radial circle of the spiral fin is connected to the support rod, and the outer radial circle is movably connected to the scraper through a pin shaft, and the scraper is distributed in an inclined manner relative to the radial direction of the connected position of the spiral fin.

[0010] Further, one end of the scraper is connected to the support rod, and the other end is connected to the inner wall of the pyrolysis furnace body and forms a blade part to scrape off the attachments on the inner wall of the pyrolysis furnace body, and the blade part is distributed at intervals from the inner wall of the pyrolysis furnace body.

[0011] Further, the first pyrolysis furnace is provided with two, and the feeding ports of the two first pyrolysis furnaces are connected to the temporary storage bin respectively, and the corresponding two discharge ports are connected to the feeding ports of the second pyrolysis furnace respectively. Or, The first pyrolysis furnace and the second pyrolysis furnace are each provided with two, the feeding ports of the two first pyrolysis furnaces are connected to the temporary storage bin respectively, the corresponding two discharge ports are one-to-one connected to the feeding ports of the two second pyrolysis furnaces, and the discharge ports of the two second pyrolysis furnaces are connected to the multi-stage cooling screw respectively.

[0012] Further, a third pyrolysis furnace is further included, the feeding port of the third pyrolysis furnace is connected to the discharge port of the first pyrolysis furnace and the temporary storage bin, and the discharge port of the third pyrolysis furnace is connected to the feeding port of the second pyrolysis furnace and the multi-stage cooling screw, and the working states of the first pyrolysis furnace, the second pyrolysis furnace and the third pyrolysis furnace are switched by switching the connection positions of the feeding port and the discharge port of the third pyrolysis furnace.

[0013] The second object of the present application is to provide a bamboo waste pyrolysis multi-generation process, which utilizes the bamboo waste pyrolysis multi-generation device provided in the first object, comprising: The bamboo waste is fed into the drying device of the feeding assembly, dried by steam from the steam boiler or waste heat from the high-temperature flue gas of the first pyrolysis furnace, and the moisture is removed; the dried bamboo waste is temporarily stored in the temporary storage bin; The dried bamboo waste in the temporary storage bin is fed into the first pyrolysis furnace for preliminary pyrolysis, and the generated solid product is further pyrolyzed in the second pyrolysis furnace; the pyrolysis gas generated in the two-stage pyrolysis process is sent into the incinerator through the outlet; The incinerator burns the pyrolysis gas to generate high-temperature flue gas, which is sequentially introduced into the second pyrolysis furnace and the first pyrolysis furnace to provide the required heat for the two-stage pyrolysis; another route of high-temperature flue gas enters the steam boiler to generate steam; the steam or waste heat flue gas discharged from the first pyrolysis furnace is transported to the drying device to realize the recycling of energy; The final solid product of the second pyrolysis furnace is output after multi-stage cooling spiral cooling, and the bamboo waste pyrolysis multi-generation process is completed.

[0014] Further, the first pyrolysis furnace and the second pyrolysis furnace each include a cylindrical pyrolysis furnace body, a spiral distributed flue gas chamber and a heat preservation layer are sequentially sleeved outside the pyrolysis furnace body, the flue gas chamber is for the flow of high-temperature flue gas, a rotating scraper is arranged in the first pyrolysis furnace and the second pyrolysis furnace for disturbance, the scraper pushes the bamboo waste towards the inner wall of the first pyrolysis furnace and the second pyrolysis furnace for heat transfer, and the scraper scrapes the adhering material adhering to the inner wall of the first pyrolysis furnace and the second pyrolysis furnace during rotation.

[0015] Compared with the prior art, the present application has the advantages and positive effects that: In view of the problem of low pyrolysis efficiency caused by poor continuity and stability of bamboo processing waste pyrolysis, a two-stage pyrolysis furnace structure is adopted, the bamboo waste is preliminarily pyrolyzed in the first pyrolysis furnace, and the product is further pyrolyzed in the second pyrolysis furnace to ensure sufficient pyrolysis of the material and optimize the product quality; the pyrolysis gas produced by the two pyrolysis furnaces is introduced into the incinerator to burn and generate high-temperature flue gas, a part of which is sequentially supplied to the second pyrolysis furnace and the first pyrolysis furnace to utilize the self-supply of burning pyrolysis gas and reduce the reliance on external energy, at the same time, the double pyrolysis furnace produces sufficient pyrolysis gas to maintain stable heat supply and prevent the heat supply from being affected by insufficient pyrolysis gas, stable pyrolysis gas production and heat supply can reduce the possibility of abnormal fluctuations in pyrolysis and rapid or uneven generation of tar, and continuous and stable pyrolysis process can avoid frequent shutdown, even if there is tar adhesion, the tar adhesion period can be prolonged, thereby ensuring the continuity of pyrolysis gas, pyrolysis efficiency and equipment life, and the steam or high-temperature flue gas output by the heat supply assembly is fed into the drying device of the feeding assembly to dry the bamboo waste in advance, so that the moisture content of the bamboo waste is reduced to a suitable level for pyrolysis, and the problems of crushing equipment failure and subsequent pyrolysis caused by high humidity are avoided.

[0016] The rotating shaft drives the support and the scraper to rotate, the helical line distributed support pushes the material to move along the axial direction of the furnace body to avoid stagnation; the scraper is movably connected through the pin shaft, and can be self-adaptively adjusted in angle according to the internal working condition of the furnace body, the blade part of the scraper is distributed at intervals with the furnace wall, so that the adhered impurities such as tar can be scraped off, and the furnace wall is avoided from being directly rubbed and damaged. The support rod is adopted to stir and scatter the material in the pyrolysis furnace body, and the heat exchange between the material and the pyrolysis furnace body is promoted.

[0017] By switching the in-out material connection position of the third pyrolysis furnace, the series number of the pyrolysis furnace can be flexibly adjusted, such as one-stage, two-stage or three-stage pyrolysis, or the standby, maintenance switching of part of the pyrolysis furnace can be realized. The adaptability of the device to the diversity of raw materials and the differentiation of products is enhanced, and the multifunctionality and operation flexibility of the system are improved. BRIEF DESCRIPTION OF DRAWINGS

[0018] The drawings constituting a part of the specification of the present application are used to provide further understanding of the present application, the schematic embodiments of the present application and the description thereof are used to explain the present application, and do not constitute improper limitation on the present application.

[0019] Figure 1 A schematic diagram of a bamboo waste pyrolysis poly-generation device in one or more embodiments of the present application.

[0020] Figure 2 A structural schematic diagram of a pyrolysis furnace body in one or more embodiments of the present application.

[0021] Figure 3 A structural schematic diagram of distribution of two first pyrolysis furnaces and one second pyrolysis furnace in one or more embodiments of the present application.

[0022] Figure 4 A structural schematic diagram of distribution of two first pyrolysis furnaces and two second pyrolysis furnaces in one or more embodiments of the present application.

[0023] Figure 5 A structural schematic diagram of distribution of one first pyrolysis furnace, one second pyrolysis furnace and one third pyrolysis furnace in one or more embodiments of the present application.

[0024] In the figure, 1 is raw material, 2 is raw material bin, 3 is screening equipment, 4 is crushing equipment, 5 is heating cavity, 6 is drying cavity inner wall, 7 is drying equipment, 8 is temporary storage bin, 9 is heat insulation cover, 10 is cylindrical structure, 11 is pyrolysis furnace body, 12 is stirring and pushing mechanism, 13 is first pyrolysis furnace, 14 is second pyrolysis furnace, 15 is multi-stage cooling spiral, 16 is incinerator, 17 is steam boiler, 18 is pyrolysis furnace body inner wall, 19 is heat preservation layer, 20 is flue gas chamber, 21 is scraper, 22 is support rod, 23 is rotating shaft, 24 is bearing, and 25 is third pyrolysis furnace. DETAILED DESCRIPTION

[0025] Embodiment 1 In a typical embodiment of the present application, as shown in Figures 1-5 A bamboo waste pyrolysis multi-cogeneration device is given.

[0026] The bamboo processing waste has a high moisture content, which can easily cause the failure rate of the crushing equipment 4 to rise, which is not conducive to the stable development of pyrolysis. A single pyrolysis furnace can easily cause incomplete pyrolysis, resulting in unstable quality of products such as biochar and pyrolysis oil. The addition of a pyrolysis furnace will increase the dependence on external energy. At the same time, the amount or quality of pyrolysis gas produced by a single pyrolysis furnace is insufficient to ensure stable heating. The tar produced by pyrolysis is easy to adhere to the furnace wall. Frequent shutdown for decoking can affect the continuity of pyrolysis gas production, pyrolysis efficiency and equipment service life. Based on this, the present embodiment provides a bamboo waste pyrolysis multi-cogeneration device, which adopts a multi-stage pyrolysis furnace structure. The pyrolysis gas produced by the multi-stage pyrolysis furnace can be introduced into the incinerator 16 to produce high-temperature flue gas. A part is sequentially heated from the second pyrolysis furnace 14 to the first pyrolysis furnace 13. The combustion of pyrolysis gas is used for self-supply heating, reducing the dependence on external energy. The double pyrolysis furnace produces sufficient pyrolysis gas to maintain stable heating and prevent the impact of insufficient pyrolysis gas on heating. Stable pyrolysis gas production and heating can reduce the abnormal fluctuations of pyrolysis and reduce the possibility of rapid or uneven generation of tar.

[0027] As shown in Figures 1-5 The bamboo waste pyrolysis multi-cogeneration device mainly includes a feeding assembly, a pyrolysis assembly and a heating assembly.

[0028] The feeding assembly mainly includes a drying equipment 7 and a temporary storage bin 8 connected to the pyrolysis assembly. The drying equipment 7 is connected to the temporary storage bin 8 for drying and storing the dried materials. In the present embodiment, the bamboo waste is used as the raw material 1 for pyrolysis multi-cogeneration, as shown in Figure 1 The raw material bin 2, screening equipment 3 and crushing equipment 4 are also included. The bamboo processing waste produced by bamboo processing is transported into the raw material bin 2 by fixed conveying or forklift transportation. The raw material bin 2 has the ability to temporarily store and transport the raw material 1. The raw material bin 2 has a certain storage volume, for example, 60 cubic meters.

[0029] When the bamboo processing waste is used as the raw material 1, it usually has a high moisture content, with a moisture content range of 30%-42%. The raw material bin 2 preferably uses a step-type raw material bin 2 and can be set below or above the ground. For easy maintenance, it is preferably set above the ground.

[0030] Different products and different processing methods of bamboo processing produce bamboo processing waste with different sizes of raw materials 1. For example, the bamboo processing waste produced by bamboo straw processing has a particle diameter or length size of less than 30mm, accounting for 60-70%.

[0031] Due to the high moisture content and fibrous nature of bamboo processing waste, it is easy to block the filter screen of the crushing device 4, and at the same time, the blade of the crushing device 4 is severely worn. Therefore, in this embodiment, the bamboo processing waste raw material 1 is first screened before crushing. The screening device 3 uses a vibrating drum screen for screening, and the screen aperture is not less than 30 mm, preferably 20 mm. After screening by the screening device 3, the raw material 1 less than 30 mm in the raw material 1 directly enters the drying device 7 for drying; the raw material 1 greater than 30 mm enters the crushing device 4 for crushing, and after crushing, it enters the drying device 7 for drying to reduce the load of the crushing device 4, prolong the service life of the crushing device 4 and reduce the failure.

[0032] Due to the high moisture content and fibrous nature of bamboo processing waste, the crushing device 4 can use a hammer crusher, and preferably a crusher without a filter screen. By extending the crushing path in the crushing device 4 and increasing the shear plate, the size of the crushed raw material 1 is ensured to be less than 30 mm. In the case of higher requirements for the size of the crushed raw material 1, a secondary screening of the crushed raw material 1 can also be used.

[0033] The drying device 7 uses a steam drying device, such as a paddle dryer or a rotary kiln pipe dryer, which has a drying chamber inside, and a heating chamber 5 is arranged outside the inner wall 6 of the drying chamber. The drying device 7 uses steam from a steam boiler 17, and the steam is introduced into the heating chamber 5, with a steam temperature not higher than 180°C. Indirect heating by steam can also be used, or high-temperature flue gas after heating the pyrolysis furnace body 11. The moisture content of the dried raw material 1 is 10-15wt%.

[0034] The dried raw material 1 enters the temporary storage bin 8 for temporary storage, and the volume of the temporary storage bin 8 is not less than 50 cubic meters, so as to ensure the use of the subsequent pyrolysis assembly when the previous processing process fails. The temporary storage bin 8 has fireproofing, anti-arching and other devices or facilities.

[0035] As shown in Figure 1 , Figure 2 , the pyrolysis assembly mainly comprises a first pyrolysis furnace 13 and a second pyrolysis furnace 14, which are connected in sequence. The feed inlet of the first pyrolysis furnace 13 is connected to the temporary storage bin 8, the discharge outlet is connected to the feed inlet of the second pyrolysis furnace 14, and the discharge outlet of the second pyrolysis furnace 14 is connected to the multi-stage cooling screw 15, which is used for cooling the product.

[0036] The heating system includes an incinerator 16 and a steam boiler 17. The pyrolysis gas outlets of the first pyrolysis furnace 13 and the second pyrolysis furnace 14 are respectively connected to the incinerator 16. The high-temperature flue gas from the incinerator 16 is sequentially connected to the second pyrolysis furnace 14 and the first pyrolysis furnace 13, and another path is connected to the steam boiler 17. The steam output from the steam boiler 17 or the high-temperature flue gas discharged from the first pyrolysis furnace 13 is connected to the drying equipment 7 to utilize waste heat. By using the steam or high-temperature flue gas output from the heating system to the drying equipment 7 of the feeding system, the bamboo waste is dried in advance, reducing its moisture content to a suitable level for pyrolysis, thus avoiding malfunctions of the crushing equipment 4 and subsequent pyrolysis problems caused by high humidity.

[0037] The system employs a two-stage pyrolysis furnace structure. Bamboo waste is initially pyrolyzed in the first pyrolysis furnace 13, and the product then enters the second pyrolysis furnace 14 for further pyrolysis. This ensures that the material is fully pyrolyzed, optimizes product quality, and improves issues such as insufficient pyrolysis and product quality.

[0038] To reduce the impact of tar adhesion, although this embodiment does not directly address tar adhesion, stable pyrolysis gas production and heating can reduce abnormal fluctuations in pyrolysis and decrease the possibility of rapid or uneven tar formation. Simultaneously, a continuous and stable pyrolysis process can avoid frequent shutdowns, and even with tar adhesion, it can extend the tar removal cycle, thereby ensuring the continuity of pyrolysis gas, pyrolysis efficiency, and equipment lifespan.

[0039] The material undergoes drying and two-stage pyrolysis, resulting in fully pyrolyzed products such as biochar and pyrolysis oil, which are of stable quality and high value. By utilizing the heat from pyrolysis gas combustion and the waste heat for drying, external energy input can be significantly reduced, achieving energy cascading and recycling. The stability of the pyrolysis process is improved, reducing downtime caused by tar cleaning or unstable heating, thus increasing pyrolysis efficiency and extending the overall service life of the equipment.

[0040] like Figure 1 As shown, the high-temperature flue gas output from the first pyrolysis furnace 13 is fed into the steam boiler 17 and mixed with another high-temperature flue gas from the incinerator 16 before entering the steam boiler 17, thus enhancing the efficiency of waste heat utilization. This avoids the waste of heat that might occur when the high-temperature flue gas from the first pyrolysis furnace 13 is directly used for drying, as the temperature is too high. The temperature of the high-temperature flue gas output from the first pyrolysis furnace 13 is measured to determine if it meets the requirements of the steam boiler 17. If so, it is prioritized for use in the steam boiler 17, reducing the problem of insufficient waste heat utilization caused by fluctuations in drying demand.

[0041] The waste heat flue gas of the first pyrolysis furnace 13 is combined with the high-temperature flue gas directly discharged from the incinerator 16, and they are jointly introduced into the steam boiler 17, which can stabilize the heat source input of the steam boiler 17, improve the steam output efficiency and stability, maximize the recovery of high-temperature flue gas heat in the system, reduce energy loss, and at the same time, ensure the continuity of steam supply, and provide more reliable energy support for the drying equipment 7 or other potential energy links.

[0042] As shown in Figure 1 and Figure 2 , the first pyrolysis furnace 13 and the second pyrolysis furnace 14 adopt the pyrolysis furnace body 11 of the cylindrical structure 10, the outer ring of the pyrolysis furnace body 11 is provided with spiral flue chambers 20, the spiral flue chambers 20 are wrapped with a heat preservation layer 19, the heat preservation layer 19 is provided with a heat shield 9, and the inside of the pyrolysis furnace body 11 is provided with a rotating shaft 23, a support and a scraper 21, as shown in Figure 2 , the inside of the pyrolysis furnace body 11 forms a pyrolysis chamber, one end of the pyrolysis chamber serves as a feeding port, and the other end serves as a discharging port, the rotating shaft 23 is rotatably installed on the end face of the pyrolysis furnace body 11 through bearings 24 at both ends, the rotating shaft 23 is coaxially distributed with the pyrolysis furnace body 11, the support is distributed in a spiral line shape around the rotating shaft 23, one end of the support is connected with the rotating shaft 23, and the other end extends to the direction of the inner wall 18 of the pyrolysis furnace body and is connected with the scraper 21.

[0043] The support is a support rod 22 and is arranged radially along the rotating shaft 23, and the scraper 21 is distributed in an inclined manner relative to the axis of the support rod 22 and is movably connected with the support rod 22 through a pin shaft.

[0044] The problems of uneven heating, material retention, tar adhesion to the furnace wall, frequent decoking and the like are common in single pyrolysis furnaces. The spiral distribution of the flue chambers 20 enables the high-temperature flue gas to flow along the furnace body in a spiral manner, prolongs the heat exchange path, improves the uniformity of the temperature in the furnace, and ensures that the pyrolysis reaction is sufficient and stable. The rotating shaft 23 drives the support and the scraper 21 to rotate, the spiral line-shaped support pushes the material to move axially along the furnace body, avoiding retention; the scraper 21 is movably connected through a pin shaft, and can adaptively adjust the angle according to the internal working condition of the furnace body, and the blade part is distributed in a spaced manner with the inner wall 18 of the pyrolysis furnace body, which can not only scrape off the adhered impurities such as tar, but also avoid direct friction and damage to the inner wall 18 of the pyrolysis furnace body. The heat transfer efficiency of the pyrolysis furnace and the uniformity of the material flow are improved, the frequency of shutdown and decoking caused by tar adhesion is reduced, the continuous operation time of the equipment is prolonged, the equipment wear is reduced, and the service life is improved.

[0045] In order to improve the pushing efficiency of the raw material 1, in the present embodiment, the support can also be a spiral fin, the radial inner circle of the spiral fin is connected with the support rod 22, and the radial outer circle is movably connected with the scraper 21 through a pin shaft, and the scraper 21 is distributed in an inclined manner relative to the radial direction of the spiral fin at the connected position.

[0046] The pyrolysis gas generated by the upper and lower pyrolysis furnaces enters the incinerator 16, and the high-temperature flue gas generated by incineration is used for heating. The combustion temperature of the incinerator 16 is 800-1000℃. One way of the high-temperature flue gas enters the lower pyrolysis furnace through the flue gas pipeline, heats the lower pyrolysis furnace, and then enters the upper pyrolysis furnace through the flue gas pipeline to heat the pyrolysis furnace body 11, and then is discharged through the flue gas pipeline. Since the discharged flue gas still has a relatively high temperature, usually above 300℃, it can be used for preheating the water inlet of the steam boiler 17 or heating the steam boiler 17, or drying the raw material 1. Then, together with the tail gas of the steam boiler 17, it enters the conventional flue gas treatment device, and after treatment, it is discharged into the atmosphere in accordance with the standard. One way of the high-temperature flue gas directly enters the steam boiler 17 to generate steam for heating.

[0047] The raw material 1 is pyrolyzed in two stages by the upper and lower pyrolysis furnaces to generate pyrolysis carbon, which is collected and stored through multi-stage cooling screws 15 and outlet pipes of the lower pyrolysis furnace.

[0048] As shown in Figure 2 , the pyrolysis furnace body 11 is internally provided with a stirring and advancing mechanism 12 composed of a rotating shaft 23, a support rod 22, and a scraper 21, which is used to turn the raw material 1 to facilitate heat transfer and gas overflow of the raw material 1, and at the same time, to push the raw material 1 to move from the inlet to the outlet. The scraper 21 is connected to the support rod 22 by a pin shaft and has a certain deflection angle with the support rod 22, so as to form a spiral arrangement in the axial direction of the rotating shaft 23. At the same time, the pin shaft connection of the scraper 21 to the support rod 22 allows the scraper 21 to have a certain degree of deflection freedom with the pin shaft as the center line. The trajectories of adjacent scrapers 21 partially overlap, and the overlapping trajectory is usually not less than 1 / 3 of the length of the scraper 21, so that the trajectory of the scraper 21 covers the entire inner surface of the furnace body. The end of the scraper 21 is provided with a certain gap, for example, 5mm, from the inner wall 18 of the pyrolysis furnace body, and the other end of the scraper 21 is connected to the pin shaft. The connecting end has a farther distance from the inner wall 18 of the pyrolysis furnace body, forming a space similar to a wedge, which continuously pushes the raw material 1 to the inner wall 18 of the pyrolysis furnace body for heat transfer when the scraper 21 rotates with the rotating shaft 23, forming auxiliary contact heat transfer and improving the heat transfer efficiency of the raw material 1.

[0049] The end of the scraper 21 has a small thickness to form a blade part for scraping the attachments on the inner wall 18 of the pyrolysis furnace body, achieving self-cleaning of the pyrolysis furnace body 11. When there are foreign matters or attachments in the raw material 1 that are too firm, the scraper 21 automatically deflects along the pin shaft connected to the support rod 22 to prevent mechanical damage or scratching of the inner surface of the furnace body.

[0050] As shown in Figure 2 , the support member is a spiral fin arranged in a spiral along the axial direction of the rotating shaft 23, and a plurality of scrapers 21 are arranged at intervals on the outer side of the spiral fin in the radial direction. The connection method of the scraper 21 to the spiral fin can refer to the connection of the support rod 22 to the scraper 21.

[0051] As shown in Figures 3-5 The single pyrolysis furnace has limited processing capacity, or the risk of overall system shutdown due to equipment failure. By parallel or corresponding series of multiple pyrolysis furnaces, the material in the temporary storage bin 8 can be distributed, and the overall processing capacity can be improved. At the same time, if a single pyrolysis furnace needs to be maintained, the remaining pyrolysis furnaces can continue to operate, ensuring system continuity, improving the processing scale and operation flexibility of the device, and reducing the risk of production interruption caused by single equipment failure.

[0052] As shown in Figure 3 The first pyrolysis furnace 13 is provided with two, and the feed inlet of the two first pyrolysis furnaces 13 is respectively connected to the temporary storage bin 8, and the corresponding two discharge outlets are respectively connected to the feed inlet of the second pyrolysis furnace 14. The two first pyrolysis furnaces 13 process the raw material 1 in parallel, and then jointly enter the second pyrolysis furnace 14 to complete the subsequent process.

[0053] The two first pyrolysis furnaces 13 simultaneously receive the pretreated bamboo waste from the temporary storage bin 8, which can distribute the raw material 1 and significantly improve the processing scale of the raw material 1 per unit time, adapt to large-scale industrial production needs, and solve the problem of limited processing capacity of a single pyrolysis furnace. When one of the first pyrolysis furnaces 13 needs to be maintained, the other can continue to operate, and the raw material 1 can still enter the second pyrolysis furnace 14 for sufficient pyrolysis, avoiding interruption of the entire pyrolysis process due to single furnace maintenance, and realizing online maintenance in a semi-production state.

[0054] The two first pyrolysis furnaces 13 can simultaneously perform preliminary pyrolysis on the raw material 1. Due to the possible differences in the composition of bamboo waste, parallel processing can to some extent balance the influence of the characteristics of the raw material 1 on preliminary pyrolysis, making the state of the raw material 1 entering the second pyrolysis furnace 14 more uniform, laying a foundation for subsequent sufficient pyrolysis, and helping to improve the stability of the quality of the final product.

[0055] During operation, the dried bamboo waste in the temporary storage bin 8 is distributed to the two first pyrolysis furnaces 13, where preliminary pyrolysis is performed (temperature range of 300-450°C, residence time not less than 20 minutes), and the solid products produced are respectively discharged from the two discharge outlets and jointly enter the second pyrolysis furnace 14; the pyrolysis gas produced by the two first pyrolysis furnaces 13 is uniformly introduced into the incinerator 16 for combustion.

[0056] The high-temperature flue gas produced by the incinerator 16 supplies heat to the second pyrolysis furnace 14 and the two first pyrolysis furnaces 13, ensuring stable pyrolysis temperature in each furnace; at the same time, the high-temperature flue gas discharged from the first pyrolysis furnace 13 and the other flue gas from the incinerator 16 are jointly introduced into the steam boiler 17, and the waste heat is fully utilized in the drying link, forming a complete energy cycle.

[0057] Without changing the segmented pyrolysis core logic, by increasing the number of first pyrolysis furnaces 13, both the processing capacity and the flexibility and risk resistance of the system operation are improved, the production loss caused by equipment maintenance is reduced, and the efficiency and economy of bamboo waste pyrolysis poly-generation are further consolidated.

[0058] As shown in Figure 4 , two first pyrolysis furnaces 13 and two second pyrolysis furnaces 14 are respectively provided, the two first pyrolysis furnaces 13 are respectively connected to the temporary storage bin 8, the two second pyrolysis furnaces 14 are respectively connected to the multi-stage cooling screw 15.

[0059] One first pyrolysis furnace 13 and one second pyrolysis furnace 14 form an independent unit, and two groups of independent units can share the processing capacity, significantly improving the overall bamboo waste processing scale of the system and adapting to the demand of industrial mass production; the two groups of units are independent of each other, and when one group (such as a first pyrolysis furnace 13 or a second pyrolysis furnace 14) needs to be shut down for maintenance (such as cleaning coking and equipment maintenance), the other group can operate normally, realizing online maintenance in a half-production state, avoiding the shutdown of the entire system due to single-group failure, and ensuring production continuity.

[0060] In operation, each group of units follows the process of preliminary pyrolysis, sufficient pyrolysis, and cooling collection, the first pyrolysis furnace 13 performs preliminary pyrolysis on the raw material 1, and the generated pyrolysis gas is connected to the incinerator 16 together with the pyrolysis gas of the other first pyrolysis furnace 13 and the two second pyrolysis furnaces 14; the high-temperature flue gas generated by the incinerator 16 is proportionally supplied to each group of pyrolysis furnaces, and the waste heat is reused to the drying link through the steam boiler 17 or the flue gas, forming an energy self-circulation. Both the optimization of product quality by segmented pyrolysis and the flexibility and risk resistance of the system by parallel grouping are enhanced, ultimately improving the efficiency and stability of bamboo waste pyrolysis poly-generation.

[0061] As shown in Figure 5 , a third pyrolysis furnace 25 is further included, the inlet of the third pyrolysis furnace 25 is connected to the outlet of the first pyrolysis furnace 13 and the temporary storage bin 8, and the outlet of the third pyrolysis furnace 25 is connected to the inlet of the second pyrolysis furnace 14 and the multi-stage cooling screw 15, and the working state of the first pyrolysis furnace 13, the second pyrolysis furnace 14 and the third pyrolysis furnace 25 is switched by switching the connection position of the inlet and outlet of the third pyrolysis furnace 25.

[0062] The moisture content and particle size of bamboo waste fluctuate, and different characteristics of raw materials 1 require different pyrolysis stages. The third pyrolysis furnace 25 can flexibly adjust the pyrolysis stage by switching the connection position: when the raw material 1 needs deeper pyrolysis, it can be connected between the first and second pyrolysis furnaces 14 to form a three-stage pyrolysis; when the raw material 1 is easy to process, it can be simplified to two-stage or even single-stage pyrolysis, matching the characteristics of the raw material 1 to optimize the product quality.

[0063] The pyrolysis furnace is prone to coking and needs frequent maintenance, and the traditional fixed process will cause system downtime. The third pyrolysis furnace 25 can replace the function of the first pyrolysis furnace 13 or the second pyrolysis furnace 14 by switching the access position when maintenance is needed. For example, if the first pyrolysis furnace 13 is shut down, the third pyrolysis furnace 25 can be directly connected to the temporary storage bin 8 and the second pyrolysis furnace 14 to undertake the preliminary pyrolysis task; if the second pyrolysis furnace 14 is shut down, the third pyrolysis furnace 25 can be connected to the discharge port of the first pyrolysis furnace 13 and the multi-stage cooling screw 15 to undertake the full pyrolysis task, ensuring that the system can still maintain a semi-production state during maintenance.

[0064] According to the fluctuation of the processing capacity, the third pyrolysis furnace 25 can flexibly adjust the number of pyrolysis furnaces participating in operation. When the processing capacity is large, multiple furnaces cooperate to improve the processing capacity; when the processing capacity is small, the number of operating furnaces is reduced to reduce energy consumption, achieving dynamic balance between efficiency and energy consumption.

[0065] The feed inlet of the third pyrolysis furnace 25 can be connected to the temporary storage bin 8 to directly receive the pretreated raw material 1, or the feed inlet of the third pyrolysis furnace 25 can be connected to the discharge port of the first pyrolysis furnace 13 to receive the preliminary pyrolysis product. When connected to the temporary storage bin 8, it can undertake part or all of the preliminary pyrolysis task; when connected to the discharge port of the first pyrolysis furnace 13, it can further pyrolyze the preliminary pyrolysis product to extend the pyrolysis time.

[0066] The discharge port of the third pyrolysis furnace 25 can be connected to the feed inlet of the second pyrolysis furnace 14 to send the pyrolysis product to the next stage, or it can be directly connected to the multi-stage cooling screw 15 to output the product. When connected to the second pyrolysis furnace 14, it participates in multi-stage pyrolysis; when directly connected to the cooling screw, it serves as a terminal pyrolysis unit, simplifying the process.

[0067] Through the above switching, various pyrolysis modes can be formed, such as a three-stage pyrolysis mode combining the first pyrolysis furnace 13, the third pyrolysis furnace 25, and the second pyrolysis furnace 14, a two-stage pyrolysis mode combining the third pyrolysis furnace 25 and the second pyrolysis furnace 14, and a two-stage pyrolysis mode combining the first pyrolysis furnace 13 and the third pyrolysis furnace 25, etc., to meet different scene requirements.

[0068] Through the flexible switching of the third pyrolysis furnace 25, the problems of poor adaptability of the fixed pyrolysis process to the characteristics of the raw material 1 and downtime caused by maintenance are solved, the dynamic matching of the pyrolysis process and the characteristics of the raw material 1 is realized, and the stability and quality of the products such as biochar and pyrolysis gas are improved; the system can still operate during single-furnace maintenance, reducing production interruption losses and adapting to the needs of industrial continuous production; the dynamic balance between processing capacity and energy consumption avoids equipment idling or excessive load, further improving the economic efficiency and practicality of the system.

[0069] Embodiment 2 In another typical embodiment of the present application, asFigures 1-5 As shown, a bamboo waste pyrolysis multi-generation process is given, and a bamboo waste pyrolysis multi-generation device as in Embodiment 1 is used.

[0070] A bamboo waste pyrolysis multi-generation process comprises the following steps: The bamboo waste is fed into the drying device 7 of the feeding assembly, dried by steam from the steam boiler 17 or the waste heat of the high-temperature flue gas from the first pyrolysis furnace 13 to remove moisture, and temporarily stored in the temporary storage bin 8; The dried bamboo waste in the temporary storage bin 8 is fed into the first pyrolysis furnace 13 for preliminary pyrolysis, and the generated solid product is further pyrolyzed in the second pyrolysis furnace 14; the pyrolysis gas generated in the two-stage pyrolysis process is sent into the incinerator 16 through the outlet, and the internal pressure of the pyrolysis furnace body 11 is kept at ±100 Pa; The incinerator 16 burns the pyrolysis gas to generate high-temperature flue gas, and the combustion temperature of the incinerator 16 is 800-1000℃, which is sequentially introduced into the second pyrolysis furnace 14 and the first pyrolysis furnace 13 to provide the required heat for the two-stage pyrolysis; the other high-temperature flue gas enters the steam boiler 17 to generate steam; the steam or the waste heat flue gas discharged from the first pyrolysis furnace 13 is transported to the drying device 7 to realize the recycling of energy; The final solid product of the second pyrolysis furnace 14 is cooled by the multi-stage cooling screw 15 and then output, and the bamboo waste pyrolysis multi-generation process is completed.

[0071] The first pyrolysis furnace 13 and the second pyrolysis furnace 14 each comprise a cylindrical pyrolysis furnace body 11, which is sequentially sleeved with a spiral flue gas chamber 20 and a heat preservation layer 19 outside, the flue gas chamber 20 is used for the flow of high-temperature flue gas, and the first pyrolysis furnace 13 and the second pyrolysis furnace 14 are provided with rotating scrapers 21 for disturbance, which push the bamboo waste to the inner wall of the first pyrolysis furnace 13 and the second pyrolysis furnace 14 for heat transfer, and the scrapers 21 scrape the attachments on the inner wall of the first pyrolysis furnace 13 and the second pyrolysis furnace 14 during rotation.

[0072] The pyrolysis temperature of the first pyrolysis furnace 13 is controlled to be 300-450℃, preferably 350-400℃, and the residence time is not less than 20 minutes; then the bamboo waste is fully pyrolyzed in the second pyrolysis furnace 14, the pyrolysis temperature is controlled to be 400-500℃, preferably 400-450℃, and the residence time is not less than 20 minutes.

[0073] The above only describes the preferred embodiments of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A multi-product device for the pyrolysis of bamboo waste, characterized in that, include: The feeding assembly includes a drying device and a temporary storage bin, with the drying device connected to the temporary storage bin; The pyrolysis assembly includes a first pyrolysis furnace and a second pyrolysis furnace. The feed inlet of the first pyrolysis furnace is connected to a temporary storage bin, and the discharge outlet is connected to the feed inlet of the second pyrolysis furnace. The discharge outlet of the second pyrolysis furnace is connected to a multi-stage cooling spiral. The heating components include an incinerator and a steam boiler. The pyrolysis gas outlets of the first pyrolysis furnace and the second pyrolysis furnace are respectively connected to the incinerator. The high-temperature flue gas from the incinerator is connected sequentially to the second pyrolysis furnace and the first pyrolysis furnace, and another path is connected to the steam boiler. The steam output from the steam boiler or the high-temperature flue gas discharged from the first pyrolysis furnace is connected to a drying device to utilize waste heat.

2. The bamboo waste pyrolysis multi-product device as described in claim 1, characterized in that, The high-temperature flue gas output from the first pyrolysis furnace is also connected to the steam boiler, and another high-temperature flue gas output from the mixed incinerator is also connected to the steam boiler.

3. The bamboo waste pyrolysis multi-product device as described in claim 1, characterized in that, Both the first and second pyrolysis furnaces include a cylindrical pyrolysis furnace body. A spirally distributed flue gas chamber and a heat insulation layer are sequentially fitted outside the pyrolysis furnace body. The flue gas chamber allows high-temperature flue gas to circulate. Inside the pyrolysis furnace body, there is a rotating shaft, support members, and scrapers. The rotating shaft is coaxially distributed with the pyrolysis furnace body. The support members are distributed at intervals around the rotating shaft in a spiral trajectory. One end of the support member is connected to the rotating shaft, and the other end extends towards the inner wall of the pyrolysis furnace body and is connected to the scraper.

4. The bamboo waste pyrolysis multi-product device as described in claim 3, characterized in that, The support member is a support rod arranged radially along the rotation axis, and the scraper is distributed at an inclination relative to the axis of the support rod and is movably connected to the support rod by a pin.

5. The bamboo waste pyrolysis multi-product device as described in claim 3, characterized in that, The support is a spiral fin, with the inner radial ring of the spiral fin connected to a support rod, and the outer radial ring movably connected to a scraper via a pin. The scraper is radially inclined relative to the spiral fin at the connected position.

6. The bamboo waste pyrolysis multi-product device as described in claim 4 or 5, characterized in that, One end of the scraper is connected to a support rod, and the other end faces the inner wall of the pyrolysis furnace and forms a blade to scrape off the deposits on the inner wall of the pyrolysis furnace. The blade is spaced apart from the inner wall of the pyrolysis furnace.

7. The bamboo waste pyrolysis multi-product device as described in claim 1, characterized in that, The first pyrolysis furnace is provided in two parts. The feed inlets of the two first pyrolysis furnaces are respectively connected to the temporary storage bin, and the corresponding two discharge outlets are respectively connected to the feed inlets of the second pyrolysis furnace. or, There are two of each of the first and second pyrolysis furnaces. The feed inlets of the two first pyrolysis furnaces are connected to temporary storage bins, and the corresponding two discharge outlets are connected to the feed inlets of the two second pyrolysis furnaces. The discharge outlets of the two second pyrolysis furnaces are connected to multi-stage cooling spirals.

8. The bamboo waste pyrolysis multi-product device as described in claim 1, characterized in that, It also includes a third pyrolysis furnace. The feed inlet of the third pyrolysis furnace is connected to the discharge outlet and temporary storage bin of the first pyrolysis furnace, and the discharge outlet of the third pyrolysis furnace is connected to the feed inlet and multi-stage cooling spiral of the second pyrolysis furnace. The working state of the first, second and third pyrolysis furnaces can be switched by switching the connection positions of the feed inlet and discharge outlet of the third pyrolysis furnace.

9. A bamboo waste pyrolysis multi-product process, utilizing the bamboo waste pyrolysis multi-product apparatus as described in any one of claims 1-8, characterized in that, include: The bamboo waste is fed into the drying equipment of the feeding assembly, and is dried by steam from the steam boiler or waste heat from the high-temperature flue gas from the first pyrolysis furnace to remove moisture; the dried bamboo waste is temporarily stored in a temporary storage silo. The dried bamboo waste in the temporary storage warehouse is sent to the first pyrolysis furnace for preliminary pyrolysis, and the resulting solid products are sent to the second pyrolysis furnace for further pyrolysis; the pyrolysis gas generated in the two-stage pyrolysis process is sent to the incinerator through the outlet. The incinerator burns pyrolysis gas to produce high-temperature flue gas, one of which is sequentially fed into the second and first pyrolysis furnaces to provide the heat required for the two-stage pyrolysis; the other high-temperature flue gas enters the steam boiler to be heated and generate steam; the steam or the waste heat flue gas discharged from the first pyrolysis furnace is transported to the drying equipment to realize the recycling of energy. The final solid product from the second pyrolysis furnace is output after being cooled by a multi-stage cooling spiral, completing the pyrolysis and multi-product process of bamboo waste.

10. The bamboo waste pyrolysis multi-product process as described in claim 9, characterized in that, Both the first and second pyrolysis furnaces include a cylindrical pyrolysis furnace body. A spirally distributed flue gas chamber and a heat insulation layer are sequentially fitted outside the pyrolysis furnace body. The flue gas chamber allows high-temperature flue gas to circulate. Rotating scrapers are installed inside the first and second pyrolysis furnaces to agitate and push the bamboo waste towards the inner walls of the first and second pyrolysis furnaces for heat transfer. During the rotation of the scrapers, the attachments on the inner walls of the first and second pyrolysis furnaces are scraped off.

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