Pyrolysis gas self-circulation biomass pyrolysis system

Abstract

The utility model belongs to the technical field of biomass pyrolysis, and discloses a pyrolysis gas self-circulation biomass pyrolysis system which comprises a raw material treatment module, a raw material input module, a continuous pyrolysis furnace, a pyrolysis gas circulation treatment module, a waste gas treatment module and a carbon storage module, the raw material input module provides biomass raw materials for the continuous pyrolyzing furnace, the continuous pyrolyzing furnace is connected with the carbon storage module, a pyrolysis gas outlet of the continuous pyrolyzing furnace is connected to the pyrolysis gas circulating treatment module, and the pyrolysis gas circulating treatment module comprises a combustion furnace for performing combustion and deoxidation treatment on pyrolysis gas. A gas outlet of the combustion furnace is connected to a heat source gas inlet of the continuous pyrolyzing furnace, the heat source gas inlet is communicated with a pyrolyzing cavity of the continuous pyrolyzing furnace, and the gas outlet of the combustion furnace is further connected to the waste gas treatment module. According to the utility model, biomass raw materials are directly heated by utilizing high-temperature flue gas generated by combustion of pyrolysis gas, so that additional fuel supplementation is avoided, the energy consumption is reduced, and the cost is also reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of biomass pyrolysis, and relates to a biomass pyrolysis system with self-circulation of pyrolysis gas. Background Art

[0002] Countries around the world are increasingly interested in the application of biomass energy. The global crisis of conventional energy supply shortages is becoming increasingly serious. The large-scale development and utilization of fossil energy has become one of the main causes of natural environmental pollution and the deterioration of the human living environment. Biomass energy has received widespread attention and is gradually being applied. Biomass pyrolysis refers to the process in which biomass absorbs heat energy at relatively low temperatures under oxygen-free or anoxic conditions, causing thermal cracking and destroying the biomass's internal macromolecular structure, converting it into solid coke, combustible gases (methane, ethylene, carbon monoxide), and liquid biomass oils (tar, wood vinegar).

[0003] Biomass pyrolysis needs to be carried out under oxygen-free or oxygen-deficient conditions. The current main technologies all use indirect heating methods using external heating of the pyrolysis furnace. The indirect heating method is safe, but the biomass cannot directly contact the heat source, the heat transfer efficiency is low, and the production cost is high. The use of conventional fuel combustion to provide a heat source has the disadvantages of high energy consumption and the generation of more pollutants. Utility Model Content

[0004] The purpose of the utility model is to provide a biomass pyrolysis system with self-circulating pyrolysis gas, so as to solve the technical problems in the prior art that the pyrolysis process uses conventional fuel to provide a heat source, usually requiring an indirect heating method, resulting in low heat transfer efficiency, high energy consumption, and high pollution.

[0005] The biomass pyrolysis system with self-circulation of pyrolysis gas comprises a raw material processing module, a raw material input module, a continuous pyrolysis furnace, a pyrolysis gas circulation treatment module, a waste gas treatment module and a charcoal storage module. The raw material processing module is connected to the raw material input module via a conveying device. The raw material input module provides biomass raw materials to the continuous pyrolysis furnace. The discharge port of the continuous pyrolysis furnace is connected to the feed port of the carbon storage module. The pyrolysis gas outlet of the continuous pyrolysis furnace is connected to the pyrolysis gas circulation treatment module. The pyrolysis gas circulation treatment module comprises a combustion furnace for combustion and deoxygenation treatment of the pyrolysis gas. The gas outlet of the combustion furnace is connected to the heat source gas inlet of the continuous pyrolysis furnace. The heat source gas inlet is connected to the pyrolysis chamber of the continuous pyrolysis furnace. The gas outlet of the combustion furnace is also connected to the waste gas treatment module.

[0006] Preferably, the pyrolysis gas circulation processing module also includes an oxygen supply and distribution fan and a pyrolysis gas fan. The pyrolysis gas fan is arranged on the pipeline between the pyrolysis gas outlet and the combustion furnace, and the oxygen distribution fan is connected to the combustion furnace for air supply and oxygen distribution; the combustion furnace is also provided with a fuel inlet for receiving fuel and an atomizing burner.

[0007] Preferably, the system also includes a drying device, the discharge port of the raw material input module is arranged at the feed port of the drying device, the drying device supplies the continuous pyrolysis furnace through a conveying device, the pyrolysis gas circulation treatment module also includes a mixed air system and a blower, the air inlet of the mixed air system and the air inlet of the heat source gas are connected in parallel to the air outlet of the combustion furnace, the blower provides normal temperature gas distribution to the mixed air system, and the air outlet of the drying device is connected to the exhaust gas treatment module.

[0008] Preferably, the raw material processing module includes a crusher and a storage bin, the crusher is connected to the feed port of the storage bin via a conveying device, and the discharge port of the storage bin is provided with a screw feeder.

[0009] Preferably, the raw material input module includes a raw material bin and a variable frequency metering feeder, the storage bin is connected to the feed port of the raw material bin through a conveying device, the discharge port of the raw material bin is provided with the variable frequency metering feeder, and the variable frequency metering feeder is used to meter and feed the raw material to the feed port of the drying device.

[0010] The present invention has the following advantages: It utilizes the high-temperature flue gas generated by the combustion of pyrolysis gas to heat the biomass raw material. The main component of the high-temperature flue gas contains only trace amounts of oxygen, and the biomass raw material is in an oxygen-deficient atmosphere, thereby enabling stable pyrolysis. The residual pyrolysis gas in the high-temperature flue gas is also recycled. This avoids the need for additional fuel, reducing both energy consumption and costs. The calorific value generated by these substances is utilized through combustion in the combustion chamber, and direct combustion purification is achieved, avoiding pollution caused by the discharge of pyrolysis gas, thus saving the corresponding gas purification equipment. In addition, the high-temperature flue gas is introduced into the biomass drying process for biomass drying after being cooled by air distribution, further reducing the energy consumption required for drying. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 The utility model is a schematic structural diagram of a biomass pyrolysis system with pyrolysis gas self-circulation.

[0012] The marks in the attached drawings are: 1. Crusher, 2. Conveying equipment, 3. Storage bin, 4. Raw material bin, 5. Frequency conversion metering feeder, 6. Drying device, 7. Continuous pyrolysis furnace, 8. Slag cooler, 9. Carbon storage bin, 10. Combustion furnace, 11. Mixed air system, 12. Purification device, 13. Bag dust collector, 14. Induced draft fan, 15. Chimney, 16. Pyrolysis gas fan, 17. Supply fan, 18. Oxygen distribution fan. DETAILED DESCRIPTION

[0013] The following is a further detailed description of the specific implementation methods of the present invention by referring to the accompanying drawings, so as to help those skilled in the art to have a more complete, accurate and in-depth understanding of the utility model concept and technical solution of the present invention.

[0014] like Figure 1 As shown, the utility model provides a biomass pyrolysis system with self-circulation of pyrolysis gas, including a raw material processing module, a raw material input module, a continuous pyrolysis furnace 7, a pyrolysis gas circulation treatment module, a waste gas treatment module and a charcoal storage module. The raw material processing module is connected to the raw material input module through a conveying device 2, and the raw material input module provides biomass raw materials to the continuous pyrolysis furnace 7. The discharge port of the continuous pyrolysis furnace 7 is connected to the feed port of the carbon storage module, and the pyrolysis gas outlet of the continuous pyrolysis furnace 7 is connected to the pyrolysis gas circulation treatment module. The pyrolysis gas circulation treatment module includes a combustion furnace 10 for combustion and deoxygenation treatment of the pyrolysis gas, and the air outlet of the combustion furnace 10 is connected to the heat source gas inlet of the continuous pyrolysis furnace 7. The heat source gas inlet is connected to the pyrolysis chamber of the continuous pyrolysis furnace 7, and the air outlet of the combustion furnace 10 is also connected to the waste gas treatment module.

[0015] In the above structure, since the heat source gas is the high-temperature flue gas generated by the combustion of pyrolysis gas, the main component of the high-temperature flue gas contains only trace amounts of oxygen, and the main components are combustion products such as carbon dioxide, and also contain a small amount of residual pyrolysis gas. Therefore, it can be directly input into the pyrolysis chamber to contact the biomass raw material to heat it. The heat transfer efficiency is high, and the pyrolysis gas, a pyrolysis product, can be utilized, avoiding the need for additional fuel, reducing energy consumption and costs. The residual pyrolysis gas generated by the combustion can be re-entered into the combustion chamber for combustion. The pyrolysis gas generated by the pyrolysis process and the liquid products vaporized by high temperature are mostly combustible substances. The calorific value generated by these substances is utilized through combustion in the combustion chamber, and direct combustion purification can be achieved, avoiding pollution caused by the discharge of pyrolysis gas, and saving the corresponding gas purification equipment.

[0016] The pyrolysis gas circulation processing module also includes an oxygen supply and distribution fan 18 and a pyrolysis gas fan 16. The pyrolysis gas fan 16 is arranged on the pipeline between the pyrolysis gas outlet and the combustion furnace 10. The oxygen distribution fan 18 is connected to the combustion furnace 10 to supply air and distribute oxygen. When distributing oxygen, attention should be paid to ensuring that the oxygen content in the flue gas after combustion is lower than the oxygen content threshold required for pyrolysis; the combustion furnace 10 is also provided with a fuel inlet for receiving fuel and an atomizing burner. Before the pyrolysis gas is produced, this system will send liquid fuel such as diesel into the fuel inlet, and then ignite and burn it through the atomizing burner to produce high-temperature flue gas.

[0017] This system also includes a drying device 6. The discharge port of the raw material input module is arranged at the feed port of the drying device 6. The drying device 6 supplies the continuous pyrolysis furnace 7 through the conveying equipment 2. The pyrolysis gas circulation treatment module also includes a mixed air system 11 and a blower 17. The air inlet of the mixed air system 11 and the air inlet of the heat source gas are connected in parallel to the air outlet of the combustion furnace 10. The blower 17 provides normal temperature gas distribution to the mixed air system 11 to control the flue gas temperature, thereby obtaining drying gas with a slightly lower temperature. The air outlet of the mixed air system 11 is connected to the air inlet of the drying device 6, and the air outlet of the drying device 6 is connected to the exhaust gas treatment module.

[0018] The raw material processing module includes a crusher 1 and a storage silo 3. The crusher 1 is connected to the feed port of the storage silo 3 via a conveyor 2. The discharge port of the storage silo 3 is equipped with a screw feeder. The crusher 1 is used to crush the biomass feedstock to a size suitable for pyrolysis. The crushed biomass feedstock is then transported to the feed port at the top of the storage silo 3 via a conveyor 2 (such as a feeding belt), where it is temporarily stored. The material in the storage silo 3 is fed by the screw feeder, and the feeding rate can be controlled.

[0019] The raw material input module includes a raw material bin 4 and a variable frequency metering feeder 5. The storage bin 3 is connected to the feed port of the raw material bin 4 through a conveying device 2. The discharge port of the raw material bin 4 is provided with the variable frequency metering feeder 5. The variable frequency metering feeder 5 is used to meter and feed the raw material to the feed port of the drying device 6, accurately control the feeding speed, and ensure that the pyrolysis process is carried out continuously.

[0020] The charcoal storage module includes a slag cooler 8, a conveying device 2, and a charcoal storage bin 9. The slag cooler 8 is located at the discharge port of the continuous pyrolysis furnace 7 and is connected to the inlet of the charcoal storage bin 9 via the conveying device 2. The biochar produced by pyrolysis is cooled by the slag cooler 8 and then transported to the charcoal storage bin 9 for storage.

[0021] The exhaust gas treatment module includes a purification device 12, a bag filter 13, an induced draft fan 14, and a chimney 15. The air inlet of the purification device 12 is connected to the air outlet of the drying device 6. The purification device 12 is connected to the chimney 15 in sequence through the bag filter 13 and the induced draft fan 14. The purification device 12 is used to purify the combustible and harmful gases remaining in the high-temperature flue gas. The bag filter 13 is used for dust removal, and the induced draft fan 14 is used to introduce the gas into the chimney 15 for discharge.

[0022] This system includes crushing and storage process, drying process, pyrolysis process and cooling and conveying process during production. The details are as follows:

[0023] 1. Biomass raw materials are transported into the factory by car, crushed by crusher 1, and then sent to storage bin 3 by feeding belt, and then sent to raw material bin 4 at a certain speed.

[0024] Second, liquid fuel (such as diesel) is fed into the combustion furnace 10, atomized and then combusted with oxygen. The high-temperature flue gas generated is respectively transported to the air mixing system 11 and the continuous pyrolysis furnace 7. The air mixing system 11 controls the temperature of the drying gas through air distribution. The drying gas and the high-temperature flue gas heat the drying device 6 and the continuous pyrolysis furnace 7 respectively.

[0025] 3. The raw material bin 4 feeds the drying device 6 via the variable frequency metering feeder 5. The feeding speed is precisely controlled according to the feeding requirements of the continuous pyrolysis. The drying device 6 uses high temperature flue gas to dry the raw material and then feeds the raw material into the continuous pyrolysis furnace 7.

[0026] 4. The pyrolysis chamber in the continuous pyrolysis furnace 7 receives high-temperature flue gas to directly heat the biomass raw material. The biomass char produced during the pyrolysis process is discharged from the discharge port, and the generated pyrolysis gas and high-temperature evaporated liquid substances are discharged from the pyrolysis gas outlet together with the pyrolysis gas.

[0027] 5. The pyrolysis gas generated by pyrolysis is sprayed into the combustion furnace 10 and burned after precise oxygen distribution. After the heat balance is achieved, the diesel combustion heat supply is stopped to realize the self-circulation of biomass pyrolysis gas for biomass pyrolysis. As the pyrolysis gas increases, the high-temperature flue gas is further cooled by air distribution and introduced into the drying device 6 for drying.

[0028] 6. The biomass char produced by pyrolysis is output to the slag cooler 8 for cooling, and then transported by the conveying equipment 2 to the charcoal storage bin 9 for storage; at the same time, the drying gas output from the drying device 6 is purified and dust-removed before being discharged.

[0029] The above is an exemplary description of the present invention in conjunction with the accompanying drawings. It is obvious that the specific implementation of the present invention is not limited to the above-mentioned method. As long as various non-substantial improvements are made using the utility model concept and technical solution of the present invention, or the utility model concept and technical solution are directly applied to other occasions without improvement, they are all within the scope of protection of the present invention.

Claims

1. A biomass pyrolysis system with pyrolysis gas self-circulation, characterized by: The invention comprises a raw material processing module, a raw material input module, a continuous pyrolysis furnace (7), a pyrolysis gas circulation treatment module, an exhaust gas treatment module and a charcoal storage module, wherein the raw material processing module is connected to the raw material input module via a conveying device (2), the raw material input module provides biomass raw materials to the continuous pyrolysis furnace (7), the discharge port of the continuous pyrolysis furnace (7) is connected to the feed port of the charcoal storage module, the pyrolysis gas outlet of the continuous pyrolysis furnace (7) is connected to the pyrolysis gas circulation treatment module, the pyrolysis gas circulation treatment module comprises a combustion furnace (10) for combustion and deoxygenation treatment of the pyrolysis gas, the gas outlet of the combustion furnace (10) is connected to the heat source gas inlet of the continuous pyrolysis furnace (7), the heat source gas inlet is connected to the pyrolysis chamber of the continuous pyrolysis furnace (7), and the gas outlet of the combustion furnace (10) is also connected to the exhaust gas treatment module.

2. The biomass pyrolysis system with pyrolysis gas self-circulation according to claim 1, characterized in that: The pyrolysis gas circulation processing module also includes an oxygen supply and distribution fan (18) and a pyrolysis gas fan (16). The pyrolysis gas fan (16) is arranged on the pipeline between the pyrolysis gas outlet and the combustion furnace (10), and the oxygen distribution fan (18) is connected to the combustion furnace (10) to supply air and oxygen; the combustion furnace (10) is also provided with a fuel inlet for receiving fuel and an atomizing burner.

3. The biomass pyrolysis system with pyrolysis gas self-circulation according to claim 2, characterized in that: It also includes a drying device (6), the discharge port of the raw material input module is arranged at the feed port of the drying device (6), the drying device (6) supplies the continuous pyrolysis furnace (7) through the conveying equipment (2), and the pyrolysis gas circulation treatment module also includes a mixed air system (11) and a blower (17), the air inlet of the mixed air system (11) and the heat source gas inlet are connected in parallel to the air outlet of the combustion furnace (10), the blower (17) provides normal temperature gas distribution air to the mixed air system (11), and the air outlet of the drying device (6) is connected to the exhaust gas treatment module.

4. The biomass pyrolysis system with pyrolysis gas self-circulation according to claim 3, characterized in that: The raw material processing module comprises a crusher (1) and a storage bin (3); the crusher (1) is connected to the feed port of the storage bin (3) via a conveying device (2); and the discharge port of the storage bin (3) is provided with a screw feeder.

5. The biomass pyrolysis system with pyrolysis gas self-circulation according to claim 4, characterized in that: The raw material input module comprises a raw material bin (4) and a variable frequency metering feeder (5); the storage bin (3) is connected to the feed port of the raw material bin (4) via a conveying device (2); the discharge port of the raw material bin (4) is provided with the variable frequency metering feeder (5); the variable frequency metering feeder (5) is used for metering and feeding the raw material to the feed port of the drying device (6).

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