An energy-saving internal and external synchronous heating continuous carbonization device and its application

Abstract

The present invention relates to the field of energy-saving pyrolysis carbonization technology, and discloses an energy-saving internal and external synchronous heating continuous carbonization device and its application. The carbonization device includes an external heating furnace body and a rotary kiln body; the rotary kiln body is placed in the middle and upper part of the external heating furnace body and penetrates the external heating furnace body. The present invention exchanges heat with part of the pyrolysis gas discharged from the rotary kiln body with high-temperature flue gas, converting it into a high-temperature heat carrier and then flowing back into the rotary kiln body; this can quickly increase the temperature at the material inlet of the rotary kiln body and make the temperature inside the entire rotary kiln body tend to be uniform, thereby achieving the internal heating effect of the rotary kiln body and enhancing the adjustability of the pyrolysis carbonization temperature level in the rotary kiln body; using the reflux pyrolysis gas as a heat carrier has less impact on the gas environment in the kiln and will not dilute the pyrolysis gas, which is convenient for the later utilization of biomass pyrolysis carbonization by-products; the reasonable arrangement of the direct-fired heating end outside the rotary kiln body and the circuitous flue end can greatly improve the utilization efficiency of the flue gas waste heat.

Description

Technical Field

[0001] The present invention relates to the technical field of energy-saving pyrolysis carbonization, and in particular to an energy-saving internal and external synchronous heating continuous carbonization device and its application. Background Art

[0002] Pyrolysis carbonization is one of the primary technologies for treating organic waste and biomass feedstock. Based on temperature, it can be divided into two types: high-temperature and low-temperature. The former, typically performed at temperatures above 300°C, rapidly decomposes biomass, primarily producing pyrolysis gas and char. The latter, performed at temperatures between 200 and 300°C, slowly decomposes biomass, resulting in biochar with low moisture content, high calorific value and energy density, good grindability and hydrophobicity, and suitability for long-distance transportation and storage. This low-temperature pyrolysis biochar can be used for secondary carbonization or gasification, producing relatively pure biogas for power generation or chemical synthesis. Furthermore, low-temperature pyrolysis carbonization retains a significant amount of aromatic organic matter, making it an excellent soil conditioner. It is particularly suitable for converting agricultural waste biomass resources such as straw and manure, promoting sustainable agriculture.

[0003] However, low-temperature pyrolysis carbonization requires a lower heating rate (less than 50°C / min) to obtain better quality. At present, continuous pyrolysis carbonization equipment is mainly based on rotary kiln carbonization furnaces, and most of them adopt a separate external heating mode. The heating temperature of the kiln surface can reach over 1000°C, resulting in extremely high internal surface temperatures or difficult to be effectively controlled. Biomass raw materials are very prone to uneven carbonization in the kiln, which is often manifested as the carbonization intensity of the biomass outside is much greater than that of the inside. Therefore, many equipment require raw materials to enter the carbonization furnace at a lower moisture content and smaller particle size to enhance carbonization uniformity, which greatly limits the efficiency and raw material adaptability of low-temperature pyrolysis carbonization. Patent application number CN201810696127.X discloses an internal and external synchronous heating carbonization device to promote the uniformity of the carbonization process, but the internal heating of the device adopts a radiation electric heating device, which has problems such as high energy consumption and low heat conduction efficiency; Patent CN220012533U discloses an internal heating continuous carbonization furnace, which also adopts electric heating; Patent application number CN201711020672.9 also discloses an internal heating carbonization furnace. Although its heat energy comes from the combustion heat of the fuel, the heating method is a less efficient radiation heating method.

[0004] Therefore, due to the difficulty in controlling low-temperature carbonization and the high energy consumption, the development and application potential of low-temperature carbonization of biomass are severely restricted. There is an urgent need for an energy-saving internal and external synchronous heating continuous carbonization device and its application. Summary of the Invention

[0005] The purpose of the present invention is to provide a technical solution to exchange heat between part of the pyrolysis gas discharged from the rotary kiln body and the high-temperature flue gas, and use the reflux pyrolysis gas as a heat carrier to internally heat the rotary kiln, so as to solve the problems in the prior art raised in the above background technology.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] An energy-saving internal and external synchronous heating continuous carbonization device, comprising:

[0008] Externally heated furnace body and rotary kiln body;

[0009] The rotary kiln body is placed in the middle and upper part of the external heating furnace body and passes through the external heating furnace body, and a rotating seal is provided at the penetration point;

[0010] Also included are a reflow pyrolysis gas heater and an air preheater;

[0011] The high-temperature flue gas generated inside the external heating furnace body is passed into the reflux pyrolysis gas heater. The pyrolysis gas generated inside the rotary kiln body is also passed into the reflux pyrolysis gas heater. The high-temperature flue gas heats the pyrolysis gas inside the reflux pyrolysis gas heater, and the heated pyrolysis gas flows back into the rotary kiln body.

[0012] The flue gas and exhaust gas generated inside the external heating furnace body are passed into the air preheater, and the air required for combustion inside the external heating furnace body is also passed into the air preheater. The flue gas and exhaust gas preheat the air inside the air preheater.

[0013] Preferably, the high-temperature flue gas of the external heating furnace body is passed into the reflux pyrolysis gas heater through the high-temperature flue gas external exhaust pipe, and the high-temperature flue gas after heat exchange inside the reflux pyrolysis gas heater is refluxed to the inside of the external heating furnace body through the high-temperature flue gas reflux pipe.

[0014] Preferably, the pyrolysis gas generated inside the rotary kiln body is passed into the reflux pyrolysis gas heater through the pyrolysis gas reflux pipe, and the reflux pyrolysis gas heater is connected to a pyrolysis gas disperser through the pyrolysis gas reflux pipe. The heated pyrolysis gas is evenly dispersed inside the rotary kiln body through the pyrolysis gas disperser; the pyrolysis gas disperser is arranged in the center of the rotary kiln body and close to the junction of the external heating furnace body and the rotary kiln body.

[0015] Preferably, a biomass feeder and a biochar discharger are respectively provided at both ends of the rotary kiln body, and the biomass feeder and the biochar discharger are both installed with the rotary kiln body through a rotating seal, and a feed port is provided on the biomass feeder;

[0016] The biochar discharging device is provided with a discharging port; rotary kiln driving devices are also provided at both ends of the rotary kiln body; and a fuel burner for heating the rotary kiln body is provided inside the external heating furnace body.

[0017] Preferably, the biochar discharger is connected to a reflux pyrolysis gas heater via a pyrolysis gas reflux pipe, and the biochar discharger is further connected to a pyrolysis gas condenser and a wood vinegar collection tank via a pyrolysis gas exhaust pipe.

[0018] Preferably, the fuel burner is supplied with fuel through a fuel pipeline, and the air preheated by the air preheater is connected to the fuel pipeline through the air pipeline; the pyrolysis gas condenser is also connected to the fuel pipeline through a pyrolysis gas exhaust pipe to burn the incompletely condensed pyrolysis gas as fuel, and valves are provided at the inlet of the fuel pipeline and on the pyrolysis gas exhaust pipe.

[0019] Preferably, the interior of the external heating furnace body includes a main combustion chamber and a detour flue, the end of the detour flue of the external heating furnace body is connected to the air preheater through an external exhaust flue, a first flue partition is provided at one end of the interior of the external heating furnace body, and a second flue partition is provided at one end of the outer wall of the rotary kiln body, the first flue partition and the first flue partition are both configured as annular partitions, and a certain distance is provided between the first flue partitions to form a detour flue.

[0020] Preferably, the reflux pyrolysis gas heater includes a heat exchange chamber and connecting chambers at both ends, the connecting chambers at both ends are connected by a heat exchange tube, the heat exchange tube is located in the heat exchange chamber, and the interior of the heat exchange chamber is provided with a first spoiler and a second spoiler arranged perpendicular to the heat exchange tube, and the first spoiler and the second spoiler are provided with clearance holes, and the clearance holes of the first spoiler and the second spoiler are staggered, and the high-temperature flue gas entering the heat exchange chamber needs to pass through the clearance holes of the first spoiler and the second spoiler;

[0021] A smoke inlet is provided at one end of the top of the heat exchange chamber, a waste outlet is provided at one end of the bottom of the heat exchange chamber, and a smoke outlet is provided at the other end of the bottom of the heat exchange chamber. The smoke outlet is connected to the external heating furnace body.

[0022] Preferably, a scraper is provided inside the heat exchange chamber and reciprocates along the axial direction of the heat exchange chamber. The scraper passes through the clearance holes of the first spoiler and the second spoiler. The scraper is provided with multiple groups of scraper holes, which respectively correspond to the multiple groups of heat exchange tubes inside the heat exchange chamber.

[0023] A bidirectional screw and a positioning rod are provided on the heat exchange chamber. The upper thread of the scraper is engaged with the bidirectional screw, and the lower part of the scraper is slidably engaged with the positioning rod. Under the drive of the bidirectional screw by the driving motor, the scraper reciprocates to scrape the outer surface of the heat exchange tube to prevent high-temperature flue gas from being deposited on the outer surface of the heat exchange tube and affecting the heat exchange efficiency of the heat exchange tube.

[0024] The present invention also provides an application of an energy-saving internal and external synchronous heating continuous carbonization device, comprising the following steps:

[0025] The fuel burner is ignited and the rotary kiln drive device is started at the same time. When the air temperature at the rotary kiln outlet begins to rise rapidly, biomass raw materials are continuously fed into the feed port through the biomass feeder.

[0026] By coordinating the flame size of the fuel burner and the rotation speed of the rotary kiln, the outlet temperature of the rotary kiln is stabilized at 200°C;

[0027] Open the valve of the flue gas pipeline connecting the external heating furnace body and the reflux pyrolysis gas heater, and simultaneously start the circulation fan located on the reflux pyrolysis gas and high-temperature flue gas pipelines to promote heat exchange between the high-temperature flue gas and the reflux pyrolysis gas. The high-temperature flue gas pipeline includes a high-temperature flue gas exhaust pipe and a high-temperature flue gas return pipe;

[0028] By adjusting the circulation fan flow on the high-temperature flue gas pipeline, the reflux pyrolysis gas temperature is controlled between 200-350℃;

[0029] When the carbonization device is operating stably, monitor the pyrolysis gas temperature at the outlet of the rotary kiln body. This temperature can be used as a reference value for the pyrolysis carbonization temperature in the rotary kiln body. If the temperature at the outlet of the rotary kiln body is lower than the required pyrolysis carbonization temperature, increase the pyrolysis gas recirculation ratio, and simultaneously increase the flow rate of the high-temperature flue gas circulation fan and the fuel supply of the fuel burner to increase the heat carrying capacity of the reflux pyrolysis gas.

[0030] Technical effects and advantages of the present invention: The energy-saving internal and external synchronous heating continuous carbonization device and its application proposed by the present invention have the following advantages compared with the existing technology:

[0031] The present invention exchanges heat between part of the pyrolysis gas discharged from the rotary kiln body and the high-temperature flue gas, converting it into a high-temperature heat carrier and then flowing back into the rotary kiln body; this can quickly increase the temperature at the material inlet of the rotary kiln body and make the temperature inside the entire rotary kiln body tend to be uniform, thereby achieving an internal heating effect of the rotary kiln body and enhancing the adjustability of the pyrolysis and carbonization temperature level in the rotary kiln body; using the reflux pyrolysis gas as a heat carrier has a small impact on the gas environment in the kiln and does not dilute the pyrolysis gas, which is convenient for the later utilization of the by-products of biomass pyrolysis and carbonization; the reasonable arrangement of the direct-fired heating end outside the rotary kiln body and the circuitous flue end can greatly improve the utilization efficiency of the flue gas waste heat; non-electric internal heating and utilization of the flue gas waste heat can effectively improve the thermal utilization efficiency and energy-saving effect of the pyrolysis and carbonization furnace. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a schematic diagram of the front structure of the carbonization device of the present invention;

[0033] Figure 2 It is a side structural schematic diagram of the carbonization device of the present invention;

[0034] Figure 3This is a schematic structural diagram of the external heating furnace body and the rotary kiln body of the present invention;

[0035] Figure 4 For the present invention Figure 3 Schematic diagram of the enlarged structure at A in the middle;

[0036] Figure 5 This is a schematic diagram of the internal structure of the reflux pyrolysis gas heater of the present invention;

[0037] Figure 6 For the present invention Figure 5 Schematic diagram of the enlarged structure at B in the middle;

[0038] Figure 7 Schematic diagram of the structure of the first spoiler, the second spoiler and the scraper in the present invention;

[0039] Figure 8 The figure is a flow chart of the steps of applying the carbonization device of the present invention.

[0040] In the picture:

[0041] 1. External heating furnace body; 2. Rotary kiln body; 3. Reflux pyrolysis gas heater; 4. Feed port; 5. Biomass feeder; 6. Biochar discharger; 7. Discharge port; 8. Pyrolysis gas exhaust pipe; 9. Pyrolysis gas condenser; 10. Wood vinegar collection tank;

[0042] 11. Fuel burner; 12. Rotary kiln drive device; 13. Rotating seal; 14. Circuitous flue; 15. External flue; 16. Pyrolysis gas return pipe; 17. Pyrolysis gas disperser; 18. High-temperature flue gas external exhaust pipe; 19. High-temperature flue gas return pipe; 20. Air preheater; 21. Air pipeline; 22. Fuel pipeline; 141. First flue baffle; 142. Second flue baffle;

[0043] 31. Connecting cavity; 32. Heat exchange cavity; 33. Heat exchange tube; 34. First spoiler; 35. Second spoiler; 36. Smoke inlet; 37. Smoke exhaust port; 38. Waste exhaust port; 39. Scraper; 310. Bidirectional screw rod; 311. Positioning rod; 312. Scraper hole; 313. Clearance hole. DETAILED DESCRIPTION

[0044] The subject matter described herein will now be discussed with reference to exemplary embodiments. It should be understood that these embodiments are discussed solely to enable those skilled in the art to better understand and implement the subject matter described herein, and that the functions and arrangements of the elements discussed may be varied without departing from the scope of this specification. Various examples may omit, substitute, or add various processes or components as needed. In addition, features described with respect to some examples may also be combined in other examples.

[0045] The invention provides Figures 1-8 As shown, an energy-saving internal and external synchronous heating continuous carbonization device comprises:

[0046] External heating furnace body 1 and rotary kiln body 2;

[0047] The rotary kiln body 2 is placed in the middle and upper part of the external heating furnace body 1 and passes through the external heating furnace body 1. A rotary seal 13 is provided at the penetration point.

[0048] It also includes a reflux pyrolysis gas heater 3 and an air preheater 20;

[0049] The high-temperature flue gas generated inside the external heating furnace body 1 is passed into the reflux pyrolysis gas heater 3. The pyrolysis gas generated inside the rotary kiln body 2 is also passed into the reflux pyrolysis gas heater 3. The high-temperature flue gas heats the pyrolysis gas inside the reflux pyrolysis gas heater 3. The heated pyrolysis gas flows back into the rotary kiln body 2.

[0050] The flue gas and exhaust gas generated inside the external heating furnace body 1 are passed into the air preheater 20 , and the air required for combustion inside the external heating furnace body 1 is also passed into the air preheater 20 . The flue gas and exhaust gas preheat the air inside the air preheater 20 .

[0051] The high-temperature flue gas of the external heating furnace body 1 is passed into the reflux pyrolysis gas heater 3 through the high-temperature flue gas external exhaust pipe 18 , and the high-temperature flue gas after heat exchange in the reflux pyrolysis gas heater 3 is refluxed to the inside of the external heating furnace body 1 through the high-temperature flue gas reflux pipe 19 .

[0052] Working principle: The present invention exchanges heat between part of the pyrolysis gas discharged from the rotary kiln body 2 and the high-temperature flue gas, so that it becomes a high-temperature heat carrier and then flows back into the rotary kiln body 2; this can quickly increase the temperature at the material inlet of the rotary kiln body 2 and make the internal temperature of the entire rotary kiln body 2 tend to be uniform, thereby achieving the internal heating effect of the rotary kiln body 2 and enhancing the adjustability of the pyrolysis carbonization temperature level in the rotary kiln body 2; using the reflux pyrolysis gas as a heat carrier has less impact on the gas environment in the kiln and will not dilute the pyrolysis gas, which is convenient for the later utilization of biomass pyrolysis carbonization by-products; the reasonable arrangement of the direct-fired heating end outside the rotary kiln body 2 and the circuitous flue 14 end can greatly improve the utilization efficiency of the flue gas waste heat; non-electric internal heating and utilization of flue gas waste heat can effectively improve the thermal utilization efficiency and energy-saving effect of the pyrolysis carbonization furnace.

[0053] The pyrolysis gas generated inside the rotary kiln body 2 is passed into the reflux pyrolysis gas heater 3 through the pyrolysis gas reflux pipe 16. The reflux pyrolysis gas heater 3 is connected to the pyrolysis gas disperser 17 through the pyrolysis gas reflux pipe 16. The heated pyrolysis gas is evenly dispersed inside the rotary kiln body 2 through the pyrolysis gas disperser 17. The pyrolysis gas disperser 17 is used to evenly disperse the heated reflux pyrolysis gas in the rotary kiln body 2. The pyrolysis gas disperser 17 is arranged in the center of the rotary kiln body 2 and close to the junction of the external heating furnace body 1 and the rotary kiln body 2 to avoid uneven heating, heat loss and smoke backflow from the feed inlet 4.

[0054] Specifically, the reflux pyrolysis gas heater 3 should adopt a tubular high-temperature flue gas heat exchanger, and the flow direction of the reflux pyrolysis gas should be opposite to or perpendicular to that of the high-temperature flue gas; the high-temperature flue gas is taken from the corresponding position of the middle and lower part of the rotary kiln body 2 inside the external heating furnace body 1; the high-temperature flue gas returns to the external heating furnace body 1 after passing through the reflux pyrolysis gas heater 3, and should be discharged to the corresponding position of the middle and upper part of the rotary kiln body 2; the reflux pyrolysis gas heater 3 and the external heating furnace body 1 are connected by a high-temperature smoke pipe; an insulation layer should be provided on the outer layer of the high-temperature smoke pipe to prevent heat loss; a valve should be provided on the high-temperature smoke pipe to adjust the flow of flue gas through the reflux pyrolysis gas heater 3, thereby controlling the temperature to which the reflux pyrolysis gas is heated.

[0055] As inherent structures of the rotary kiln body 2, a biomass feeder 5 and a biochar discharger 6 are respectively provided at both ends of the rotary kiln body 2. The biomass feeder 5 and the biochar discharger 6 are both mounted to the rotary kiln body 2 via a rotating seal 13. The biomass feeder 5 is provided with a feed port 4; the biochar discharger 6 is provided with a discharge port 7. A rotary kiln drive device 12 is also provided at both ends of the rotary kiln body 2. A fuel burner 11 for heating the rotary kiln body 2 is provided inside the external heating furnace body 1. Specifically, a spiral structure is provided inside the rotary kiln body 2. During the rotation of the rotary kiln body 2, the biomass raw materials inside the rotary kiln body 2 will move, that is, move from the biomass feeder 5 toward the biochar discharger 6. Electric air-locking discharge valves are installed at the inlets and outlets of the biomass feeder 5 and the biochar discharger 6 to control the feed and discharge speeds and maintain an oxygen-deficient environment within the rotary kiln.

[0056] The biochar discharger 6 is connected to the reflux pyrolysis gas heater 3 via the pyrolysis gas reflux pipe 16. The biochar discharger 6 is also connected to the pyrolysis gas condenser 9 and the wood vinegar collection tank 10 via the pyrolysis gas exhaust pipe 8. The pyrolysis gas condenser 9 is preferably water-cooled, and a partition-type heat exchanger or a spray-type heat exchanger can be selected.

[0057] The fuel burner 11 is supplied with fuel via a fuel line 22. Air preheated by the air preheater 20 is connected to the fuel line 22 via an air line 21. The pyrolysis gas condenser 9 is also connected to the fuel line 22 via a pyrolysis gas exhaust pipe 8, allowing the incompletely condensed pyrolysis gas to be burned as fuel. Valves are provided at the inlet of the fuel line 22 and on the pyrolysis gas exhaust pipe 8. Specifically, the air preheater 20 is placed at an appropriate location on the exhaust gas pipeline of the external heating furnace body 1, and a smoke exhaust fan should be installed on the flue gas pipeline at the rear end of the air preheater 20 to balance the resistance to smoke exhaust created by the flue gas preheater.

[0058] like Figure 3 and Figure 4 The interior of the external heating furnace body 1 includes a main combustion chamber and a detour flue 14. The end of the detour flue 14 of the external heating furnace body 1 is connected to the air preheater 20 through an external exhaust flue 15. A first flue baffle 141 is provided at one end of the interior of the external heating furnace body 1, and a second flue baffle 142 is provided at one end of the outer wall of the rotary kiln body 2. The first flue baffle 141 and the first flue baffle 141 are both configured as annular baffles, and a certain distance is provided between the first flue baffle 141 and the first flue baffle 141 to form a detour flue 14. Specifically, the externally heated furnace body 1 is provided with an insulation layer on the exterior; a circuitous flue 14 is provided on the interior, located near the feed side of the rotary kiln body 2. The circuitous flue 14 comprises flue gas baffles fixed to the interior of the furnace body and the exterior of the rotary kiln body 2. The circuitous flue 14 effectively utilizes the waste heat of the flue gas generated by external heating to preheat and remove moisture from the fresh material in the feed side rotary kiln body 2, thereby achieving energy conservation during the carbonization process. The circuitous flue 14 is connected to a smoke duct on the exterior of the externally heated furnace body 1. The smoke duct is equipped with a smoke exhaust fan and a dust removal device, preferably a cyclone dust collector or a bag dust collector.

[0059] like Figure 5 and Figure 6 As shown, the reflux pyrolysis gas heater 3 includes a heat exchange chamber 32 and connecting chambers 31 at both ends. The connecting chambers 31 at both ends are connected by a heat exchange pipe 33. The heat exchange pipe 33 is located in the heat exchange chamber 32. The interior of the heat exchange chamber 32 is provided with a first spoiler 34 and a second spoiler 35 arranged perpendicular to the heat exchange pipe 33. The first spoiler 34 and the second spoiler 35 are provided with a clearance hole 313. The clearance holes 313 of the first spoiler 34 and the second spoiler 35 are staggered. The high-temperature flue gas entering the heat exchange chamber 32 needs to pass through the clearance holes 313 of the first spoiler 34 and the second spoiler 35; a smoke inlet 36 is provided at one end of the top of the heat exchange chamber 32, a waste outlet 38 is provided at one end of the bottom of the heat exchange chamber 32, and a smoke exhaust port 37 is provided at the other end of the bottom of the heat exchange chamber 32. The smoke exhaust port 37 is connected to the external heating furnace body 1.

[0060] like Figures 5 to 7 As shown, the heat exchange chamber 32 is provided with a scraper 39 that reciprocates along the axial direction of the heat exchange chamber 32, and the scraper 39 passes through the give way holes 313 of the first spoiler 34 and the second spoiler 35. The scraper 39 is provided with multiple groups of scraping holes 312, and the multiple groups of scraping holes 312 correspond to the multiple groups of heat exchange tubes 33 inside the heat exchange chamber 32; the heat exchange chamber 32 is provided with a bidirectional screw rod 310 and a positioning rod 311, the upper part of the scraper 39 is threadedly engaged with the bidirectional screw rod 310, and the lower part of the scraper 39 is slidably engaged with the positioning rod 311. Under the drive of the bidirectional screw rod 310 by the driving motor, the scraper 39 reciprocates to scrape the outer surface of the heat exchange tube 33 to prevent high-temperature flue gas from depositing on the outer surface of the heat exchange tube 33 and affecting the heat exchange efficiency of the heat exchange tube 33.

[0061] like Figure 8 The present invention also provides an application of an energy-saving internal and external synchronous heating continuous carbonization device, comprising the following steps:

[0062] The fuel burner 11 is ignited and the rotary kiln drive device 12 is started at the same time. When the outlet air temperature of the rotary kiln body 2 begins to rise rapidly, the biomass raw material begins to enter the feed port 4 through the biomass feeder 5.

[0063] By coordinating the flame size of the fuel burner 11 and the rotation speed of the rotary kiln body 2, the outlet temperature of the rotary kiln body 2 is stabilized at 200°C;

[0064] Open the valve of the flue gas pipeline connecting the external heating furnace body 1 and the reflux pyrolysis gas heater 3, and simultaneously start the circulation fan located on the reflux pyrolysis gas and high-temperature flue gas pipelines to promote heat exchange between the high-temperature flue gas and the reflux pyrolysis gas. The high-temperature flue gas pipeline includes a high-temperature flue gas exhaust pipe 18 and a high-temperature flue gas return pipe 19;

[0065] By adjusting the circulation fan flow on the high-temperature flue gas pipeline, the reflux pyrolysis gas temperature is controlled between 250-350℃;

[0066] When the carbonization device is operating stably, monitor the temperature of the pyrolysis gas at the outlet of the rotary kiln body 2. This temperature can be used as a reference value for the pyrolysis carbonization temperature in the rotary kiln body 2. If the temperature at the outlet of the rotary kiln body 2 is lower than the required pyrolysis carbonization temperature, increase the pyrolysis gas recirculation ratio, and simultaneously increase the flow rate of the high-temperature flue gas circulation fan and the fuel supply of the fuel burner 11 to increase the heat carrying capacity of the reflux pyrolysis gas.

[0067] The above describes the specific implementation of this embodiment, but this embodiment is not limited to the above specific implementation. The above specific implementation is merely illustrative and not restrictive. Ordinary technicians in this field can also make many forms based on the inspiration of this embodiment, all of which are protected by this embodiment.

Claims

1. An energy-saving internal and external synchronous heating continuous carbonization device, characterized in that: include: An external heating furnace body (1) and a rotary kiln body (2); The rotary kiln body (2) is placed in the middle and upper part of the external heating furnace body (1) and passes through the external heating furnace body (1), and a rotating seal (13) is provided at the penetration point; Also included is a reflux pyrolysis gas heater (3) and an air preheater (20); The high-temperature flue gas generated inside the external heating furnace body (1) is passed into the reflux pyrolysis gas heater (3), and the pyrolysis gas generated inside the rotary kiln body (2) is also passed into the reflux pyrolysis gas heater (3). The high-temperature flue gas heats the pyrolysis gas inside the reflux pyrolysis gas heater (3), and the heated pyrolysis gas flows back into the rotary kiln body (2); The flue gas and exhaust gas generated inside the external heating furnace body (1) are passed into the air preheater (20), and the external air is also passed into the air preheater (20). The flue gas and exhaust gas preheat the air inside the air preheater (20) and then pass into the fuel burner (11) inside the external heating furnace body (1); The high-temperature flue gas of the external heating furnace body (1) is passed into the reflux pyrolysis gas heater (3) through the high-temperature flue gas external exhaust pipe (18); the high-temperature flue gas after heat exchange in the reflux pyrolysis gas heater (3) is refluxed into the internal part of the external heating furnace body (1) through the high-temperature flue gas reflux pipe (19); The reflux pyrolysis gas heater (3) includes a heat exchange chamber (32) and connecting chambers (31) at both ends. The connecting chambers (31) at both ends are connected through a heat exchange tube (33). The heat exchange tube (33) is located in the heat exchange chamber (32). A first spoiler (34) and a second spoiler (35) are provided inside the heat exchange chamber (32) and are arranged perpendicular to the heat exchange tube (33). The first spoiler (34) and the second spoiler (35) are provided with a clearance hole (313). The clearance holes (313) of the first spoiler (34) and the second spoiler (35) are staggered. The high-temperature flue gas entering the heat exchange chamber (32) needs to pass through the clearance holes (313) of the first spoiler (34) and the second spoiler (35). A smoke inlet (36) is provided at one end of the top of the heat exchange chamber (32), a waste outlet (38) is provided at one end of the bottom of the heat exchange chamber (32), and a smoke outlet (37) is provided at the other end of the bottom of the heat exchange chamber (32), and the smoke outlet (37) is connected to the external heating furnace body (1); A scraper (39) is provided inside the heat exchange cavity (32) and reciprocates along the axial direction of the heat exchange cavity (32). The scraper (39) passes through the clearance holes (313) of the first spoiler (34) and the second spoiler (35). The scraper (39) is provided with multiple groups of scraper holes (312). The multiple groups of scraper holes (312) respectively correspond to the multiple groups of heat exchange tubes (33) inside the heat exchange cavity (32). A bidirectional screw (310) and a positioning rod (311) are provided on the heat exchange chamber (32); the upper thread of the scraper (39) is engaged with the bidirectional screw (310); the lower part of the scraper (39) is slidably engaged with the positioning rod (311); and when the bidirectional screw (310) is driven by the driving motor, the scraper (39) reciprocates to scrape the outer surface of the heat exchange tube (33) to prevent high-temperature flue gas from being deposited on the outer surface of the heat exchange tube (33) and affecting the heat exchange efficiency of the heat exchange tube (33).

2. The energy-saving internal and external synchronous heating continuous carbonization device according to claim 1 is characterized in that: The pyrolysis gas generated inside the rotary kiln body (2) is passed into the reflux pyrolysis gas heater (3) through the pyrolysis gas reflux pipe (16); the reflux pyrolysis gas heater (3) is connected to the pyrolysis gas disperser (17) through the pyrolysis gas reflux pipe (16); the heated pyrolysis gas is evenly dispersed inside the rotary kiln body (2) through the pyrolysis gas disperser (17); the pyrolysis gas disperser (17) is arranged at the center of the rotary kiln body (2) and close to the junction of the external heating furnace body (1) and the rotary kiln body (2).

3. The energy-saving internal and external synchronous heating continuous carbonization device according to claim 2 is characterized in that: A biomass feeder (5) and a biochar discharger (6) are respectively provided at both ends of the rotary kiln body (2); the biomass feeder (5) and the biochar discharger (6) are both mounted on the rotary kiln body (2) via a rotating seal (13); and a feed port (4) is provided on the biomass feeder (5); The biochar discharger (6) is provided with a discharge port (7); rotary kiln drive devices (12) are also provided at both ends of the rotary kiln body (2); and a fuel burner (11) for heating the rotary kiln body (2) is provided inside the external heating furnace body (1).

4. The energy-saving internal and external synchronous heating continuous carbonization device according to claim 3 is characterized in that: The biochar discharger (6) is connected to the reflux pyrolysis gas heater (3) via the pyrolysis gas reflux pipe (16), and the biochar discharger (6) is also connected to the pyrolysis gas condenser (9) and the wood vinegar collection tank (10) via the pyrolysis gas external exhaust pipe (8).

5. The energy-saving internal and external synchronous heating continuous carbonization device according to claim 4 is characterized in that: The fuel burner (11) is supplied with fuel via a fuel pipeline (22), and the air preheated by the air preheater (20) is connected to the fuel pipeline (22) via an air pipeline (21); the pyrolysis gas condenser (9) is also connected to the fuel pipeline (22) via a pyrolysis gas exhaust pipe (8) so as to burn the uncondensed pyrolysis gas as fuel, and valves are provided at the inlet of the fuel pipeline (22) and on the pyrolysis gas exhaust pipe (8).

6. The energy-saving internal and external synchronous heating continuous carbonization device according to claim 1 is characterized in that: The interior of the external heating furnace body (1) includes a main combustion chamber and a detour flue (14). The end of the detour flue (14) of the external heating furnace body (1) is connected to the air preheater (20) through an external exhaust flue (15). A first flue baffle (141) is provided at one end of the interior of the external heating furnace body (1). A second flue baffle (142) is provided at one end of the outer wall of the rotary kiln body (2). The first flue baffle (141) and the second flue baffle (142) are both configured as annular baffles. A certain distance is provided between the first flue baffle (141) and the second flue baffle (142) to form a detour flue (14).

7. Application of the energy-saving internal and external synchronous heating continuous carbonization device according to claim 1, characterized in that: The steps include: The fuel burner (11) is ignited and the rotary kiln drive device (12) is started simultaneously. When the air temperature at the outlet of the rotary kiln body (2) begins to rise rapidly, the biomass raw material begins to enter the feed port (4) continuously through the biomass feeder (5); By cooperatively adjusting the flame size of the fuel burner (11) and the rotation speed of the rotary kiln body (2), the outlet temperature of the rotary kiln body (2) is stabilized at a set temperature; Opening the valve of the flue gas pipeline connecting the external heating furnace body (1) and the reflux pyrolysis gas heater (3), and simultaneously starting the circulation fan located on the reflux pyrolysis gas and high-temperature flue gas pipelines to promote heat exchange between the high-temperature flue gas and the reflux pyrolysis gas, wherein the high-temperature flue gas pipeline includes a high-temperature flue gas external exhaust pipe (18) and a high-temperature flue gas return pipe (19); By adjusting the circulation fan flow on the high-temperature flue gas pipeline, the reflux pyrolysis gas temperature is controlled between 250-350℃; When the carbonization device is in stable operation, the temperature of the pyrolysis gas at the outlet of the rotary kiln body (2) is monitored, and this temperature can be used as a reference value for the pyrolysis carbonization temperature in the rotary kiln body (2); if the temperature at the outlet of the rotary kiln body (2) is lower than the required pyrolysis carbonization temperature, the pyrolysis gas recirculation ratio is increased, and the flow rate of the high-temperature flue gas circulation fan and the fuel supply of the fuel burner (11) are simultaneously increased to increase the heat carrying capacity of the reflux pyrolysis gas.

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