Straw pyrolysis carbonization device and straw pyrolysis carbon gas co-production method

Abstract

The invention discloses a straw pyrolysis carbonization device and a straw pyrolysis carbon gas co-production method, and relates to the technical field of agricultural machineries, the straw pyrolysis carbonization device comprises a pre-carbonization system and a pyrolysis system, the pre-carbonization system comprises a pre-carbonization channel, a straw conveying assembly and a cutter set, the pre-carbonization channel is provided with a straw inlet and a straw outlet, and the cutter set is provided with a cutter set; the cutter group is arranged at the straw outlet and is used for breaking and crushing the bundled straws to form straw pre-carbonized powder; the pyrolysis system is provided with a pyrolysis inlet, a pyrolysis outlet and an exhaust air duct, the pyrolysis inlet is communicated with the straw outlet to receive the straw pre-carbonized powder, the pyrolysis system pyrolyzes the straw pre-carbonized powder to generate biochar, the biochar is discharged through the pyrolysis outlet, the exhaust air duct is communicated with the pre-carbonization channel, waste heat of the pyrolysis system is used for pre-carbonizing bundled straw, and the straw pre-carbonized powder is discharged through the pyrolysis outlet. The straw pretreatment energy consumption and the treatment cost are reduced, and by means of the straw pyrolysis carbon gas co-production method, co-production of pyrolysis gas and biochar can be achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of agricultural machinery, and in particular to a straw pyrolysis carbonization device and a straw pyrolysis carbonization gas co-production method. Background Art

[0002] Currently, a large amount of straw resources are abandoned and burned, causing environmental pollution. Pyrolysis carbonization technology can effectively convert straw into biochar, achieving efficient utilization of straw resources, reducing carbon emissions and protecting the environment. Therefore, straw pyrolysis carbonization and straw charcoal applications have received widespread attention.

[0003] Continuous biomass pyrolysis carbonization and gas cogeneration technology is widely used in straw pyrolysis carbonization due to its continuous production and scalable application. However, existing continuous straw carbonization technologies are not suitable for carbonizing whole straw bales. Instead, they crush the straw to a specific particle size before feeding it into a reactor for pyrolysis carbonization. This increases straw pretreatment energy consumption and processing costs, hindering industrial development. Summary of the Invention

[0004] The purpose of the present invention is to provide a straw pyrolysis carbonization device and a straw pyrolysis carbonization gas co-production method, which can adapt to the carbonization of whole bundles of straw, reduce pretreatment energy consumption and treatment costs, and solve the problems existing in the above-mentioned prior art.

[0005] To achieve the above object, the present invention provides the following solutions: The present invention provides a straw pyrolysis carbonization device, comprising a pre-carbonization system and a pyrolysis system, the pre-carbonization system comprising a pre-carbonization channel, a straw conveying assembly and a knife group, the pre-carbonization channel is provided with a straw inlet for allowing bundles of straw to pass through and a straw outlet with an opening facing downward, the straw conveying assembly is arranged in the pre-carbonization channel, and is used to convey the bundles of straw from the straw inlet to the straw outlet, the knife group is arranged at the straw outlet, and is used to break and crush the bundles of straw to form straw pre-carbonized powder; the pyrolysis system is provided with a pyrolysis inlet, a pyrolysis outlet and an exhaust air duct, the pyrolysis inlet is connected with the straw outlet, and is used to receive the straw pre-carbonized powder, the pyrolysis system can pyrolyze the straw pre-carbonized powder to produce biochar, the pyrolysis outlet can discharge the biochar, and the exhaust air duct is connected with the pre-carbonization channel to discharge the waste heat of the pyrolysis system to the pre-carbonization channel for pre-carbonizing the bundles of straw.

[0006] In some embodiments, the pyrolysis system includes a rotary kiln, a combustion furnace and an air distribution pipe, the pyrolysis inlet is the inlet of the rotary kiln, the pyrolysis outlet is the outlet of the rotary kiln, and the furnace wall of the rotary kiln is provided with a plurality of pyrolysis gas outlets for the escape of pyrolysis gas formed during the pyrolysis process of the straw pre-carbonized powder; the rotary kiln is rotatably arranged inside the combustion furnace, and the pyrolysis gas can enter the combustion furnace through the pyrolysis gas outlet; the exhaust air duct is provided on the chamber wall of the combustion furnace; the air distribution pipe is provided in the combustion furnace, and the air distribution pipe is used to introduce air into the combustion furnace for sufficient combustion of the pyrolysis gas and to heat the rotary kiln. The waste heat of the pyrolysis system is the flue gas generated when the rotary kiln is heated.

[0007] In some embodiments, the plurality of pyrolysis gas outlets are evenly distributed in the axial and circumferential directions of the rotary kiln; and at least one pyrolysis gas outlet is provided around each of the air distribution pipes.

[0008] In some embodiments, the straw pyrolysis carbonization device also includes an online monitoring system arranged in the combustion furnace, and the online monitoring system includes a plurality of detection probes, each of which is surrounded by at least one pyrolysis gas outlet, and the detection probe is used to detect the components of the pyrolysis gas and the concentration of each component; each of the air distribution pipes is provided with a valve, and the valve is communicatively connected to the online monitoring equipment, and the valve can adjust the exhaust flow of the air distribution pipe according to the detection value of the detection probe.

[0009] In some embodiments, the pre-carbonization channel is arranged at the top of the combustion furnace, and the exhaust duct includes a plurality of exhaust ports arranged on the top chamber wall of the combustion furnace, and the plurality of exhaust ports are evenly distributed along the length direction of the pre-carbonization channel.

[0010] In some embodiments, the straw pyrolysis carbonization device also includes a conveying mechanism, which includes: a connecting channel, a distributor and a driving device, the inlet end of the connecting channel is sealedly connected to the straw outlet, and the outlet end of the connecting channel is sealedly connected to the pyrolysis inlet; the connecting channel is used to convey the straw pre-carbonized powder; the distributor is arranged at the pyrolysis inlet, for conveying the straw pre-carbonized powder to the pyrolysis system; the driving device is connected to the distributor, for driving the distributor.

[0011] In some embodiments, the straw pyrolysis carbonization device further includes a carbon collection system, and the inlet of the carbon collection system is sealedly connected to the pyrolysis outlet for collecting the biochar.

[0012] In some embodiments, the pre-carbonization system is a push-plate furnace, the straw inlet is the inlet of the push-plate furnace, and the straw outlet is the outlet of the push-plate furnace; the pre-carbonization system also includes a flue gas outlet and an induced draft fan, the flue gas outlet is arranged at one end of the outlet of the push-plate furnace, and the induced draft fan is arranged at the flue gas outlet to guide the flue gas in the push-plate furnace to be discharged through the flue gas outlet.

[0013] In some embodiments, the knife group includes: a rotating shaft, a knife group and a motor, the rotating shaft is rotatably arranged on the side wall of the pre-carbonization channel; the knife group is detachably connected to the rotating shaft; the motor is connected to the rotating shaft, and is used to drive the rotating shaft to rotate, so that the knife group breaks and crushes the bundled straw.

[0014] The present invention also discloses a straw pyrolysis carbonization gas co-production method implemented using the above-mentioned straw pyrolysis carbonization device, comprising: pre-carbonizing the bundled straw through the pre-carbonization channel; breaking and crushing the pre-carbonized bundled straw through the knife group to form the straw pre-carbonized powder; receiving the straw pre-carbonized powder through the pyrolysis system to pyrolyze the straw pre-carbonized powder and generate biochar; and discharging the waste heat of the pyrolysis system to the pre-carbonization channel to provide the pre-carbonization channel with heat for pre-carbonizing the bundled straw.

[0015] Compared with the prior art, the present invention has achieved the following technical effects: The present invention provides a straw pyrolysis and carbonization device. Straw bundles are directly placed into a pre-carbonization system for pre-carbonization, and then broken and pulverized by a blade assembly. Because the straw becomes brittle and easier to break apart after pre-carbonization, undried straw is tougher and more difficult to break, resulting in higher energy consumption. Therefore, compared to the method of first crushing the straw to a certain particle size before feeding it into a reactor for pyrolysis and carbonization, the present invention directly pre-carbonizes the straw bundles before breaking and pulverizing them, thereby reducing processing energy consumption and processing costs. Furthermore, the high temperature in the pre-carbonized straw partially breaks the straw fibers, increasing microporosity and specific surface area, which facilitates the full pyrolysis of the straw and improves the quality of the pyrolysis gas produced by the straw pyrolysis.

[0016] The present invention also provides a straw pyrolysis carbonization gas co-production method, which solves the problem that bundled straw cannot be continuously pyrolyzed and carbonized, and can discharge the waste heat of the pyrolysis system to the pre-carbonization channel, and use the waste heat of the pyrolysis system to pre-carbonize the bundled straw, thereby reducing the energy consumption of straw pre-carbonization and realizing the co-production of pyrolysis gas and biochar from bundled straw. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 This is a schematic diagram of the overall structure of the straw pyrolysis and carbonization device in the first embodiment disclosed in the present invention; Figure 2 This is a flow chart of the straw pyrolysis charcoal gas co-generation method in Example 2 disclosed in the present invention.

[0019] In the figure: 100-straw pyrolysis carbonization device; 110-pre-carbonization system; 11-pre-carbonization channel; 12-straw conveying assembly; 13-knife group; 14-straw inlet; 15-straw outlet; 16-flue gas outlet; 200-pyrolysis system; 21-pyrolysis inlet; 22-pyrolysis outlet; 23-exhaust air duct; 24-rotary kiln; 241-pyrolysis gas outlet; 25-combustion furnace; 26-air distribution duct; 300-conveyance mechanism; 31-connecting channel; 32-distributor; 33-drive device; 400-carbon collection system. DETAILED DESCRIPTION

[0020] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0021] The purpose of the present invention is to provide a straw pyrolysis carbonization device and a straw pyrolysis carbonization gas co-generation method, which can carbonize straw in bundles, reduce pretreatment energy consumption and treatment costs, and solve the problems existing in the above-mentioned prior art.

[0022] In order to make the above-mentioned objects, features and advantages of the present invention more clearly understood, the following Figures 1 and 2 The present invention is further described in detail with reference to the accompanying drawings and specific embodiments.

[0023] Example 1 This embodiment provides a straw pyrolysis carbonization device 100, referring to Figure 1, including a pre-carbonization system 110 and a pyrolysis system 200, the pre-carbonization system 110 includes a pre-carbonization channel 11, a straw conveying assembly 12 and a knife group 13, the pre-carbonization channel 11 is provided with a straw inlet 14 for allowing bundles of straw to pass through and a straw outlet 15 with an opening facing downward, the straw conveying assembly 12 is arranged in the pre-carbonization channel 11, and is used to convey the bundles of straw from the straw inlet 14 to the straw outlet 15, and the knife group 13 is arranged at the straw outlet 15, and is used to break the bundles of straw and crush them , to form straw pre-carbonized powder; the pyrolysis system 200 is provided with a pyrolysis inlet 21, a pyrolysis outlet 22 and an exhaust duct 23. The pyrolysis inlet 21 is connected to the straw outlet 15 for receiving the straw pre-carbonized powder. The pyrolysis system 200 can pyrolyze the straw pre-carbonized powder to produce biochar. The pyrolysis outlet 22 can discharge the biochar. The exhaust duct 23 is connected to the pre-carbonization channel 11 to discharge the waste heat of the pyrolysis system 200 to the pre-carbonization channel 11 to pre-carbonize the bundled straw. The straw pyrolysis carbonization device 100 provided in this embodiment is to directly put the bundled straw into the pre-carbonization system 110 for pre-carbonization, and then break the bundle and crush it by the knife group 13. Since the straw becomes brittle after pre-carbonization, it is easier to break up, while the undried straw has strong toughness, is more difficult to break, and consumes more energy. Therefore, compared with the method of first crushing the straw to a certain particle size and then sending it into the reactor for pyrolysis carbonization, the present invention directly pre-carbonizes the bundled straw and then breaks the bundle and crushes it, which can reduce the processing energy consumption and processing cost of the straw. In addition, the straw that has been pre-carbonized is partially broken due to the high temperature, the microscopic porosity increases, and the specific surface area increases, which is conducive to the full pyrolysis of the straw and can also improve the quality of the pyrolysis gas produced by the pyrolysis of the straw. In addition, the downward opening in this embodiment is not vertically downward in the absolute sense. The opening can be set in the form of an angle with the horizontal plane to form an inclined opening to facilitate the actual assembly and application of the straw pyrolysis carbonization device 100.

[0024] In some embodiments, reference Figure 1The pyrolysis system 200 includes a rotary kiln 24, a combustion furnace 25 and an air distribution pipe 26. The pyrolysis inlet 21 is the entrance of the rotary kiln 24, and the pyrolysis outlet 22 is the outlet of the rotary kiln 24. The furnace wall of the rotary kiln 24 is provided with a plurality of pyrolysis gas outlets 241 for the escape of pyrolysis gas generated during the pyrolysis process of straw pre-carbonized powder; the rotary kiln 24 is rotatably arranged inside the combustion furnace 25, and the pyrolysis gas can enter the combustion furnace 25 through the pyrolysis gas outlet 241; the chamber wall of the combustion furnace 25 is provided with an exhaust air duct 23; the air distribution pipe 26 is arranged in the combustion furnace 25, and the air distribution pipe 26 is used to introduce air into the combustion furnace 25 for sufficient combustion of the pyrolysis gas and to heat the rotary kiln 24. The waste heat of the pyrolysis system 200 is the flue gas generated when the rotary kiln 24 is heated. In this embodiment, the rotary kiln 24 is a horizontal rotary kiln, the rotating axis of the rotary kiln 24 is arranged horizontally, and a spiral blade coaxially arranged with the rotating axis of the rotary kiln 24 is fixed in the rotary kiln 24. The straw pre-carbonized powder can move from the inlet to the outlet under the drive of the spiral blade as the rotary kiln 24 rotates. At the same time, the straw pre-carbonized powder can also roll in the rotary kiln 24, so that the straw pre-carbonized powder can be fully pyrolyzed in the rotary kiln 24. The pyrolysis gas enters the combustion furnace 25 through the pyrolysis gas outlet 241, and air is introduced into the combustion furnace 25 through the air distribution pipe 26. The pyrolysis gas is ignited to release heat to heat the rotary kiln 24, providing heat for the pyrolysis of the straw pre-carbonized powder, which can achieve full utilization of the pyrolysis gas. By using the pyrolysis gas to heat the rotary kiln 24, the energy consumption of heating the rotary kiln 24 is saved, and the energy consumption of pyrolysis of the straw pre-carbonized powder is reduced. In some other embodiments, a rotary kiln 24 with a rotating shaft at a certain angle to the horizontal plane can be used to pyrolyze the straw pre-carbonized powder. In some other embodiments, the spiral blades in the rotary kiln 24 can be replaced by an agitator.

[0025] In some embodiments, reference Figure 1, a plurality of pyrolysis gas outlets 241 are evenly distributed in the axial and circumferential directions of the rotary furnace 24 ; and at least one pyrolysis gas outlet 241 is provided around each air distribution pipe 26 . The pyrolysis gas outlets 241 are evenly distributed in the axial and circumferential directions of the rotary furnace 24. In this embodiment, the pyrolysis gas outlets 241 are evenly arranged in multiple circles in the axial direction of the rotary furnace 24, and each circle is also provided with multiple pyrolysis gas outlets 241. The multiple pyrolysis gas outlets 241 are evenly distributed in the circumferential direction of the rotary furnace 24. Specifically, in this embodiment, three pyrolysis gas outlets 241 are arranged in a single circle in the circumference of the rotary furnace 24, and the angle between each two pyrolysis gas outlets 241 is 120°. In addition, the axial spacing of the pyrolysis gas outlets 241 in each circle in the rotary furnace 24 is 1m~1.5m, and three air distribution ducts 26 are also provided in a circle, and the angle between each two air distribution ducts 26 is 120 degrees, and the axial setting position of the air distribution duct 26 in the combustion furnace 25 is aligned with the axial setting position of the pyrolysis gas outlet 241 in the rotary furnace 24. In some other embodiments, other arrangements may be provided according to actual conditions, such as spirally opening the pyrolysis gas outlet 241 on the rotary kiln 24 and aligning the axial position of the air distribution pipe 26 in the combustion furnace 25 with the axial position of the pyrolysis gas outlet 241 on the rotary kiln 24.

[0026] In some embodiments, reference Figure 1 The straw pyrolysis carbonization device 100 also includes an online monitoring system arranged in the combustion furnace 25. The online monitoring system includes several detection probes, each of which is surrounded by at least one pyrolysis gas outlet 241. The detection probe is used to detect the components and concentrations of the pyrolysis gas; each air distribution pipe 26 is provided with a valve, which is in communication with the online monitoring device and can adjust the exhaust flow of the air distribution pipe 26 according to the detection value of the detection probe. By detecting the components and concentrations of the pyrolysis gas by the detection probe and controlling the opening of the valve according to the detection value of the detection probe, exhaust can be achieved according to the components and concentrations of the pyrolysis gas, and the ratio of pyrolysis gas to air is controlled to 1:2~1:4 to achieve full combustion and heat release of the pyrolysis gas, while also avoiding the generation of harmful substances produced by incomplete combustion of the pyrolysis gas, which is more environmentally friendly. In this embodiment, the detection probe is specifically a TDLS8100 / TDLS8200 online gas analyzer produced by Yokogawa Electric (China) Co., Ltd. In other embodiments, other equipment that can detect the components and concentrations of the pyrolysis gas can also be selected according to actual conditions. When the pyrolysis system 200 is not working, the exhaust flow rate of the air distribution pipe 26 is 0, and the valve is closed.

[0027] In some embodiments, reference Figure 1The pre-carbonization channel 11 is provided at the top of the combustion furnace 25, and the exhaust duct 23 includes a plurality of exhaust ports provided on the top wall of the combustion furnace 25, and the plurality of exhaust ports are evenly distributed along the length of the pre-carbonization channel 11. By providing the plurality of exhaust ports evenly distributed along the length of the pre-carbonization channel 11, the flue gas generated by the combustion of the pyrolysis gas can be evenly introduced into the pre-carbonization channel 11, thereby evenly pre-carbonizing the bundles of straw in the pre-carbonization channel 11. The pre-carbonization degree of the bundles of straw at various locations in the pre-carbonization channel 11 is made uniform, thereby improving the uniformity of the pre-carbonization degree of the straw pre-carbonized powder and thus improving the quality of the pyrolysis gas.

[0028] In some embodiments, reference Figure 1 The straw pyrolysis carbonization device 100 further includes a conveying mechanism 300, which includes: a connecting channel 31, a distributor 32, and a driving device 33. The inlet end of the connecting channel 31 is sealedly connected to the straw outlet 15, and the outlet end of the connecting channel 31 is sealedly connected to the pyrolysis inlet 21. The connecting channel 31 is used to convey straw pre-carbonized powder. The distributor 32 is provided at the pyrolysis inlet 21 and is used to convey straw pre-carbonized powder to the pyrolysis system 200. The driving device 33 is connected to the distributor 32 and is used to drive the distributor 32. By providing the connecting channel 31, the inlet end of the connecting channel 31 is sealedly connected to the straw outlet 15, and the outlet end of the connecting channel 31 is sealedly connected to the pyrolysis inlet 21. This ensures that smoke will not overflow from the connecting channel 31, thereby avoiding environmental pollution. It also prevents the straw pre-carbonized powder from flying out and affecting the working environment of on-site personnel. By setting a distributor 32, the driving device 33 drives the distributor 32 to distribute the powder to the rotary kiln 24, so that the straw pre-carbonized powder can smoothly enter the rotary kiln 24. In this embodiment, the distributor 32 is a distribution plate and is arranged obliquely. The driving device 33 includes a driving motor, a cam and a connecting rod. One end of the connecting rod is hinged to the edge of the cam, and the other end is hinged to the top of the distributor 32. The bottom of the distributor 32 is rotatably connected to the pyrolysis inlet 21. The output end of the driving motor is connected to one side of the cam to drive the cam to rotate. The rotation of the cam drives the connecting rod to move, thereby driving the top of the distributor 32 to shake up and down, thereby causing the straw pre-carbonized powder on the distributor 32 to be shaken into the rotary kiln 24, achieving uniform distribution of the straw pre-carbonized powder, thereby making the straw pre-carbonized powder more uniformly heated and pyrolyzed, and improving the quality of the pyrolysis gas. In some other embodiments, the distributor 32 may be a spreading shaft driven by the driving device 33 to rotate, and a spreading blade is provided on the spreading shaft. The straw pre-carbonized powder is evenly distributed into the rotary kiln 24 under the spreading action of the spreading blade. In some other embodiments, the distributor 32 may also be other structures that can achieve uniform distribution of the rotary kiln 24.

[0029] In some embodiments, reference Figure 1The straw pyrolysis carbonization device 100 also includes a carbon collection system 400, and the inlet of the carbon collection system 400 is sealed and connected to the pyrolysis outlet 22 for collecting biochar. By setting the carbon collection system 400 and making the inlet of the carbon collection system 400 and the pyrolysis outlet 22 sealed and connected, in this embodiment, the carbon collection system 400 also includes a sealed channel and a carbon collection box, the inlet of the sealed channel is sealed and connected to the pyrolysis outlet 22, and the outlet of the sealed channel is sealed and connected to the inlet of the carbon collection box. The biochar enters the carbon collection box through the sealed channel from the pyrolysis outlet 22. This can prevent the biochar from flying out during the collection process and affecting the working environment and health of the operator. The collected biochar can be applied to the soil to improve the physical and chemical properties of the soil, increase the soil's fertility, water holding capacity and air permeability, and adjust the soil pH to better provide for the growth of crops.

[0030] In some embodiments, reference Figure 1 The pre-carbonization system 110 is a push plate furnace, the straw inlet 14 is the inlet of the push plate furnace, and the straw outlet 15 is the outlet of the push plate furnace; the pre-carbonization system 110 also includes a flue gas outlet 16 and an induced draft fan. The flue gas outlet 16 is provided at one end of the outlet of the push plate furnace, and the induced draft fan is provided at the flue gas outlet 16 to guide the flue gas in the push plate furnace to be discharged through the flue gas outlet 16. The push plate furnace is provided with a push plate, a guide rail and a propulsion system that provides driving force for the push plate. The push plate is pushed forward under the guidance of the guide rail, and the bundles of straw are placed on the push plate and move from the inlet of the push plate furnace to the outlet of the push plate furnace. The pre-carbonization system 110 can also be a chain furnace or other furnace type. By providing an induced draft fan, the flue gas can be discharged from the flue gas outlet 16. In this embodiment, the flue gas outlet 16 is also provided with a dust removal device or a filter device to remove dust from the flue gas, so that the discharged flue gas is within the legal range and avoids pollution to the environment. An induced draft fan can also be provided in the pre-carbonization channel 11 to guide the flow of flue gas in the pre-carbonization channel 11 so that the flue gas flows away from the straw inlet 14, thereby avoiding heat waste caused by high-temperature flue gas escaping from the straw inlet 14.

[0031] In some embodiments, reference Figure 1The blade assembly 13 comprises a rotating shaft, a blade assembly, and a motor. The rotating shaft is rotatably mounted on the sidewall of the pre-carbonization channel 11. The blade assembly is detachably connected to the rotating shaft. The motor is connected to the rotating shaft and drives the rotating shaft to rotate, causing the blade assembly to break and pulverize the straw bundles. The blade selection of the blade assembly enables the straw bundles to be pulverized into smaller particles, ensuring sufficient pyrolysis of the straw. Furthermore, the blade assembly is detachably connected to the rotating shaft, allowing the blade distribution of the blades on the blade assembly 13 to be adjusted according to the size of the straw bundles, ensuring sufficient pulverization. The blade assembly can be detachably connected to the rotating shaft by bolts or snap-on connections. The blade assembly can be a single blade with a fixed base or a ring of blades fixed to a ring base. Furthermore, the blades of the blades are spaced 10 to 15 cm apart to ensure sufficient pulverization of the straw bundles. Furthermore, both the blade assembly and the rotating shaft are made of high-temperature resistant materials to withstand high-temperature working environments.

[0032] Example 2 This embodiment provides a straw pyrolysis carbonization device 100 implemented in the first embodiment of the straw pyrolysis carbonization method, referring to Figure 2, including pre-carbonizing the input straw bundles through the pre-carbonization channel 11; breaking and crushing the pre-carbonized straw bundles through the knife group 13 to form straw pre-carbonized powder; receiving the straw pre-carbonized powder through the pyrolysis system 200 to pyrolyze the straw pre-carbonized powder and generate biochar; the waste heat of the pyrolysis system 200 is discharged to the pre-carbonization channel 11 to provide the pre-carbonization channel 11 with heat for pre-carbonizing the straw bundles. In this embodiment, the pyrolysis system 200 adopts a rotary kiln 24. When in use, the rotation speed of the rotary kiln 24 is first adjusted and the rotary kiln 24 is ignited to heat it. The residual heat from the heating enters the pre-carbonization channel 11 through the exhaust duct 23. After the bundles of straw are pre-carbonized, the straw pre-carbonized powder formed after the bundles are broken and crushed by the knife group 13 is evenly fed into the rotary kiln 24 by the distributor 32 for pyrolysis. The generated pyrolysis gas is discharged into the combustion furnace chamber through the pyrolysis gas outlet 241 evenly distributed along the axial and circumferential directions of the rotary kiln 24. The pyrolysis gas is mixed and burned with the air introduced through the air distribution pipe 26 in the combustion furnace chamber. The heat of combustion is used to heat the rotary kiln 24. The flue gas generated by the combustion enters the pre-carbonization channel 11 through the exhaust duct 23 to dehydrate, dry and pre-carbonize the bundles of straw. After the pyrolysis of the straw pre-carbonized powder is completed, the generated biochar is discharged through the pyrolysis outlet 22 and enters the carbon collection system 400. The rotary kiln 24 is heated by burning pyrolysis gas generated by pyrolysis of straw pre-carbonized powder, and the flue gas generated by the combustion of pyrolysis gas enters the pre-carbonization channel 11 to pre-carbonize the bundled straw, thereby solving the problem that the whole bundle of straw cannot be continuously pyrolyzed and carbonized. The pyrolysis gas outlets 241 are evenly arranged on the rotary kiln 24 to allow the pyrolysis gas to precipitate in an orderly manner. The pyrolysis gas is efficiently burned in the combustion furnace 25 and the waste heat of the high-temperature flue gas is utilized to pre-carbonize the bundled straw. While reducing the energy consumption of straw pyrolysis, the clean heating of the pyrolysis gas of the straw bale and the co-production of biochar are realized, in order to promote the development of straw pyrolysis technology.

[0033] Example 3 This embodiment is a pyrolysis carbonization and gas co-production of corn straw. First, the rotary kiln 24 is started and ignited by firewood or diesel. The chamber temperature of the rotary kiln 24 is first heated to 600°C. The speed of the rotary kiln 24 is set to ensure that the residence time of the corn straw pre-carbonized powder in the kiln is 40-50 minutes. Then, the whole bundles of corn straw packaged in the field are continuously put into the entrance of the push plate furnace. After pre-carbonization in the push plate furnace and bale breaking and crushing by the knife group 13, the corn straw pre-carbonized powder enters the connecting channel 31 and falls onto the distributor 32. The pre-carbonized corn stalk powder is evenly transported to the rotary kiln 24 via a distributor 32. Once inside, the pre-carbonized corn stalk powder begins to pyrolyze due to the low oxygen and high temperature. The resulting pyrolysis gas is discharged through the surrounding pyrolysis gas outlets 241 and fully combusted within the combustion chamber 25. The generated heat is first used to heat the rotary kiln 24. Flue gas at approximately 300°C enters the pre-carbonization channel 11 through the exhaust duct 23 on the top wall of the combustion chamber 25, providing heat for drying and pre-carbonizing the bundled corn stalks. It is ultimately discharged through the flue gas outlet 16 via an induced draft fan. The biochar produced by the pyrolysis of the pre-carbonized corn stalk powder in the rotary kiln 24 enters the carbon collection system 400.

[0034] Example 4 This embodiment is a pyrolysis carbonization gas co-production of rice / wheat straw. First, the rotary kiln 24 is started, and the temperature of the chamber of the rotary kiln 24 is heated to 550°C by ignition with firewood or diesel. The speed of the rotary kiln 24 is set to ensure that the residence time of the rice / wheat straw pre-carbonized powder in the furnace is 30min-40min. Then, the rice / wheat straw bundles packaged in the field are continuously put into the entrance of the push plate furnace. After pre-carbonization in the push plate furnace and breaking and crushing by the knife group 13, the rice / wheat straw pre-carbonized powder enters the connecting channel 31 and falls onto the distributor 32. The pre-carbonized rice / wheat straw powder is evenly transported to the rotary kiln 24 via a distributor 32. Once in the rotary kiln 24, the pre-carbonized rice / wheat straw powder begins to pyrolyze due to the low oxygen and high temperature. The resulting pyrolysis gas is discharged through the surrounding pyrolysis gas outlets 241 and fully combusted within the combustion chamber 25. The generated heat is first used to heat the rotary kiln 24. Flue gas at approximately 200°C enters the pre-carbonization channel 11 through the exhaust duct 23 on the top wall of the combustion chamber 25, providing heat for drying and pre-carbonizing the bundled rice / wheat straw. It is ultimately discharged through the flue gas outlet 16 via an induced draft fan. The biochar produced by the pyrolysis of the pre-carbonized rice / wheat straw powder in the rotary kiln 24 enters the carbon collection system 400.

[0035] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A straw pyrolysis carbonization device, characterized by: include: A pre-carbonization system, comprising a pre-carbonization channel, a straw conveying assembly, and a knife group, wherein the pre-carbonization channel is provided with a straw inlet for allowing bundles of straw to pass through and a straw outlet with a downward opening, the straw conveying assembly is arranged in the pre-carbonization channel and is used to convey the bundles of straw from the straw inlet to the straw outlet, and the knife group is arranged at the straw outlet and is used to break and crush the bundles of straw to form pre-carbonized straw powder; and A pyrolysis system is provided with a pyrolysis inlet, a pyrolysis outlet and an exhaust duct. The pyrolysis inlet is connected to the straw outlet and is used to receive the straw pre-carbonized powder. The pyrolysis system can pyrolyze the straw pre-carbonized powder to produce biochar. The pyrolysis outlet can discharge the biochar. The exhaust duct is connected to the pre-carbonization channel to discharge the waste heat of the pyrolysis system to the pre-carbonization channel to pre-carbonize the bundled straw.

2. The straw pyrolysis carbonization device according to claim 1, characterized in that: The pyrolysis system comprises: A rotary kiln, wherein the pyrolysis inlet is the inlet of the rotary kiln, the pyrolysis outlet is the outlet of the rotary kiln, and the furnace wall of the rotary kiln is provided with a plurality of pyrolysis gas outlets for escaping the pyrolysis gas generated during the pyrolysis process of the straw pre-carbonized powder; A combustion furnace, wherein the rotary kiln is rotatably disposed inside the combustion furnace, and the pyrolysis gas can enter the combustion furnace through the pyrolysis gas outlet; the exhaust air duct is disposed on the wall of the combustion furnace; and An air distribution pipe is provided in the combustion furnace, and is used to introduce air into the combustion furnace for sufficient combustion of the pyrolysis gas and heating the rotary kiln. The waste heat of the pyrolysis system is the flue gas generated when the rotary kiln is heated.

3. The straw pyrolysis carbonization device according to claim 2, characterized in that: The plurality of pyrolysis gas outlets are evenly distributed in the axial and circumferential directions of the rotary kiln; At least one pyrolysis gas outlet is provided around each of the air distribution pipes.

4. The straw pyrolysis carbonization device according to claim 2, characterized in that: It also includes an online monitoring system disposed in the combustion furnace, the online monitoring system including a plurality of detection probes, each of which is surrounded by at least one pyrolysis gas outlet, and the detection probes are used to detect the components of the pyrolysis gas and the concentration of each component; Each of the air distribution pipes is provided with a valve, which is communicatively connected to the online monitoring device. The valve can adjust the exhaust flow of the air distribution pipe according to the detection value of the detection probe.

5. The straw pyrolysis carbonization device according to any one of claims 2 to 4, characterized in that: The pre-carbonization channel is arranged at the top of the combustion furnace, and the exhaust air duct includes a plurality of exhaust ports arranged on the top chamber wall of the combustion furnace, and the plurality of exhaust ports are evenly distributed along the length direction of the pre-carbonization channel.

6. The straw pyrolysis carbonization device according to any one of claims 1 to 4, characterized in that: Also included is a conveying mechanism, the conveying mechanism comprising: A connecting channel, wherein the inlet end of the connecting channel is sealedly connected to the straw outlet, and the outlet end of the connecting channel is sealedly connected to the pyrolysis inlet; the connecting channel is used to transport the straw pre-carbonized powder; a distributor, provided at the pyrolysis inlet, for delivering the straw pre-carbonized powder to the pyrolysis system; and A driving device is connected to the distributor and is used to drive the distributor.

7. The straw pyrolysis carbonization device according to any one of claims 1 to 4, characterized in that: It also includes a carbon collection system, the inlet of which is sealedly connected to the pyrolysis outlet for collecting the biochar.

8. The straw pyrolysis carbonization device according to any one of claims 1 to 4, characterized in that: The pre-carbonization system is a push plate furnace, the straw inlet is the inlet of the push plate furnace, and the straw outlet is the outlet of the push plate furnace; The pre-carbonization system further includes a smoke outlet and an induced draft fan. The smoke outlet is arranged at one end of the outlet of the push plate furnace. The induced draft fan is arranged at the smoke outlet to guide the smoke in the push plate furnace to be discharged through the smoke outlet.

9. The straw pyrolysis carbonization device according to any one of claims 1 to 4, characterized in that: The knife set includes: a rotating shaft rotatably disposed on a side wall of the pre-carbonization channel; a blade-flinging assembly, the blade-flinging assembly being detachably connected to the rotating shaft; and The motor is connected to the rotating shaft and is used to drive the rotating shaft to rotate so that the blade group can break and crush the bundles of straw.

10. A straw pyrolysis carbonization and gas co-generation method using the straw pyrolysis carbonization device according to any one of claims 1 to 9, characterized in that: include: Pre-carbonizing the bundled straws fed into the pre-carbonization channel; The pre-carbonized straw bundles are broken and crushed by the blade group to form the pre-carbonized straw powder; The straw pre-carbonized powder is received by the pyrolysis system to pyrolyze the straw pre-carbonized powder and generate biochar; The waste heat of the pyrolysis system is discharged to the pre-carbonization channel to provide the pre-carbonization channel with heat for pre-carbonizing the bundled straw.

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