System for preparing biochar through pyrolysis of smoked and baked biomass

Abstract

The invention discloses a system for preparing biochar through pyrolysis of smoked and baked biomass, the system comprises a smoked and baked furnace and a pyrolysis furnace, the smoked and baked furnace comprises a first discharge port, a first air inlet and a first air outlet; the pyrolysis furnace is internally provided with a pyrolysis chamber, the pyrolysis chamber is provided with a feed port, a second discharge port and a second air outlet, the feed port is communicated with the first discharge port, and the second air outlet is communicated with the first air inlet. Therefore, the biomass is continuously smoked and baked by using the pyrolysis gas through the system, so that condensable volatile matters in the pyrolysis gas are promoted to be directly condensed and attached to the biomass, and then the biochar yield and the carbon retention rate are improved by using the co-pyrolysis effect of the bio-oil and the biomass, so that more carbon elements are sealed in the biochar, and the biochar yield is improved. Therefore, the carbon sequestration effect is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of biochar, in particular to a production system for preparing biochar by pyrolysis. Background Art

[0002] Biomass energy is a widely distributed renewable energy source that is carbon neutral and can balance the emission and absorption of CO2. Although biomass has the potential to be directly converted into fuel, its high moisture content, low energy density, large volume, high fiber content, poor grindability and poor uniformity have led to a series of problems such as difficulty in transporting biomass, high cost and seasonal restrictions, which restrict its wider application.

[0003] As a biomass processing and fuel upgrading technology, pyrolysis can improve the characteristics of the raw materials themselves and produce energy and chemical products. Biomass is usually converted into three-phase products of gas, liquid and solid through pyrolysis technology, and the yield of the three-phase products is regulated by changing the pyrolysis process parameters, such as changing the pyrolysis temperature, heating rate and carrier gas flow rate. Among these three-phase products, biochar has the most potential to replace coal due to its good fuel properties (high energy density, high calorific value, high carbon content and low oxygen content).

[0004] In the traditional biomass pyrolysis process, most of the carbon is transferred to bio-oil and pyrolysis gas, resulting in low biochar yield, limited carbon retention rate and combustion performance of the generated biochar, and poor economic efficiency. Improving the charcoal yield and carbon content of biomass can seal more carbon elements in biochar, which is of great significance to achieving green and sustainable development.

[0005] Currently, there are two main ways to fix carbon by biomass pyrolysis. One is to use pressure equipment to increase the reaction pressure during biomass pyrolysis. However, pressurized pyrolysis is usually intermittent and cannot meet the high efficiency and continuity of biomass pyrolysis carbon fixation technology. At the same time, the safety of pressure equipment is also a technical problem that hinders the development of biomass pressurized pyrolysis carbon fixation. The second is to use additives and biomass mixed pyrolysis, but the use of additives will increase industrial production costs, and the addition of additives will change the composition of biomass pyrolysis products, which may affect the subsequent utilization value of the pyrolysis products. At the same time, some additives may cause pollution to the environment. Summary of the invention

[0006] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a system for preparing biochar by pyrolysis of smoked biomass, which can use pyrolysis gas to smoke biomass raw materials and then pyrolyze them, thereby sealing more carbon elements in the biomass into the biochar.

[0007] A system for preparing biochar by pyrolysis of smoked biomass according to an embodiment of the present invention comprises:

[0008] A fumigation and roasting furnace, the fumigation and roasting furnace comprising a first material discharge port, a first air inlet port and a first air outlet port;

[0009] A pyrolysis furnace, wherein a pyrolysis chamber is provided in the pyrolysis furnace, wherein the pyrolysis chamber is provided with a feed port, a second feed port and a second gas outlet, wherein the feed port is communicated with the first feed port, and the second gas outlet is communicated with the first gas inlet.

[0010] According to some embodiments of the present invention, the smoking and roasting furnace includes: a first feed box, a first rotary furnace body and a first discharge box, the two ends of the first rotary furnace body are dynamically sealed and connected to the first feed box and the first discharge box respectively, the first discharge port and the first air inlet are arranged on the first discharge box, and the first air outlet is arranged on the first feed box.

[0011] According to some embodiments of the present invention, the first rotary furnace body includes an inner furnace body and an outer furnace body, and a condensation chamber is provided between the inner furnace body and the outer furnace body.

[0012] According to some embodiments of the present invention, the condensation chamber includes a first condensation zone and a second condensation zone, the temperature of the first condensation zone is lower than the temperature of the second condensation zone, the first condensation zone is arranged on a side close to the first feed box, and the second condensation zone is arranged on a side of the first discharge box.

[0013] According to some embodiments of the present invention, a material removal plate is provided on the inner side wall of the inner furnace body.

[0014] According to some embodiments of the present invention, a hollow heat conduction chamber is provided in the material copying plate, and the heat conduction chamber is communicated with the condensation chamber.

[0015] According to some embodiments of the present invention, a burner is further included, wherein the burner includes an air inlet and an air outlet, the air inlet is connected to the first air outlet, and the air outlet is connected to the pyrolysis chamber.

[0016] According to some embodiments of the present invention, the burner further includes: a fuel inlet, a slag outlet and a mesh partition, the mesh partition is arranged above the air inlet, the fuel inlet is arranged on the burner side wall on one side of the mesh partition, and the slag outlet is arranged on the burner side wall on the other side of the mesh partition.

[0017] According to some embodiments of the present invention, the pyrolysis furnace includes: a second feed box, a second rotary furnace body and a second discharge box, the two ends of the second rotary furnace body are dynamically sealed and connected to the second feed box and the second discharge box respectively, the feed port is arranged on the second feed box, and the second air outlet and the second discharge port are arranged on the second discharge box.

[0018] Beneficial effects:

[0019] The present invention continuously utilizes pyrolysis gas to fumigate biomass through the system, thereby promoting the direct condensation and attachment of condensable volatiles in the pyrolysis gas to the biomass, and then utilizes the co-pyrolysis of bio-oil and biomass to improve the biochar yield and carbon retention rate, so that more carbon elements are sealed in the biochar, thereby achieving the effect of carbon fixation.

[0020] At the same time, the high retention rate of carbon elements in biochar is conducive to improving the combustion calorific value of biochar as an alternative fuel, enhancing the thermal stability of biochar fuel, improving the fuel performance of biochar, and making the biochar combustion process closer to fossil fuels. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0022] Figure 1 Schematic diagram of a system for preparing biochar by pyrolysis of smoked biomass according to an embodiment of the present invention;

[0023] Figure 2 Schematic diagram of the cross-sectional structure of the first rotary furnace body according to an embodiment of the present invention Figure 1 ;

[0024] Figure 3 Schematic diagram of the cross-sectional structure of the first rotary furnace body according to an embodiment of the present invention Figure 2 ;

[0025] Figure 4 Schematic diagram of the structure of a burner according to an embodiment of the present invention.

[0026] Reference numerals:

[0027] 100. Biochar preparation system by pyrolysis of smoked biomass

[0028] 1. Smoking and roasting furnace; 11. First feed box; 12. First rotary furnace body; 121. Inner furnace body; 122. Outer furnace body; 13. First discharge box; 14. First discharge port; 15. First air inlet; 16. First air outlet;

[0029] 2. pyrolysis furnace; 21. second feed box; 22. second rotary furnace body; 23. second discharge box; 24. feed port; 25. second discharge port; 26. second gas outlet;

[0030] 3. Condensation chamber; 31. First condensation zone; 32. Second condensation zone;

[0031] 4. Copying board; 41. Heat transfer chamber;

[0032] 5. Burner; 51. Air inlet; 52. Air outlet; 53. Fuel inlet; 54. Slag outlet; 55. Mesh partition. DETAILED DESCRIPTION

[0033] The following is a clear and complete description of the technical solutions in the embodiments of the present disclosure in conjunction with the drawings in the embodiments disclosed in this application. The description of the embodiments is actually only illustrative and exemplary, and does not serve as any limitation to the present disclosure and its application or use; based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without carrying out creative work should fall within the scope of protection of the present disclosure. In addition, the technologies, methods and equipment known to ordinary technicians in the relevant fields may not be discussed in detail, but where appropriate, the technologies, methods and equipment should be regarded as part of the specification.

[0034] Combination Figures 1 to 4 As shown, a system 100 for preparing biochar by pyrolysis of smoked and roasted biomass according to an embodiment of the present invention comprises at least: a smoked and roasted furnace 1 and a pyrolysis furnace 2, wherein the smoked and roasted furnace 1 comprises a first discharge port 14, a first air inlet 15 and a first air outlet 16, and a pyrolysis chamber is provided in the pyrolysis furnace 2, and the pyrolysis chamber is provided with a feed port 24, a second discharge port 25 and a second air outlet 26, wherein the feed port 24 is connected to the first discharge port 14, and the second air outlet 26 is connected to the first air inlet 15.

[0035] When in use, the biomass raw material enters the fumigation furnace 1 and comes into contact with the pyrolysis gas generated by pyrolysis in the pyrolysis furnace 2. During this process, the pyrolysis gas continuously fumigates the biomass and condenses the pyrolysis oil that adheres to the biomass particles. Finally, the biomass particles attached with the bio-oil are pyrolyzed in the pyrolysis furnace 2.

[0036] Specifically, during the pyrolysis process of the smoked and roasted biomass, the bio-oil attached to the biomass particles can close the intrinsic pore structure of the biomass and form a confined space inside the biomass structure, thereby limiting the escape of the primary products of biomass pyrolysis and causing them to remain in the biomass. The free radicals in these primary pyrolysis products (such as phenoxy groups) can cross-link with hemicellulose and cellulose, undergoing further condensation polymerization reactions, and ultimately promoting the formation of stable biochar. At this time, the condensed bio-oil can produce the effect of a carbon fixer.

[0037] Therefore, the present invention continuously utilizes pyrolysis gas to fumigate biomass through the system, thereby promoting the direct condensation and attachment of condensable volatiles in the pyrolysis gas to the biomass, and then utilizes the co-pyrolysis of bio-oil and biomass to improve the biochar yield and carbon retention rate, so that more carbon elements are sealed in the biochar, thereby achieving the effect of carbon fixation, so that the carbon element retention rate of the produced biochar is high, which is beneficial to improving the combustion calorific value of biochar as an alternative fuel, enhancing the thermal stability of biochar fuel, improving the fuel performance of biochar, and making the biochar combustion process closer to fossil fuels.

[0038] Furthermore, on the basis of the above embodiment, as shown in the figure, the smoking and roasting furnace 1 includes: a first feed box 11, a first rotary furnace body 12 and a first discharge box 13, the two ends of the first rotary furnace body 12 are dynamically sealed and connected to the first feed box 11 and the first discharge box 13 respectively, the first discharge port 14 and the first air inlet 15 are arranged on the first discharge box 13, and the first air outlet 16 is arranged on the first feed box 11.

[0039] When in use, the biomass raw material enters from the first feed box 11, is constantly turned in the first rotary furnace, is constantly mixed with the pyrolysis gas, and finally moves to the first discharge box 13 and leaves through the first discharge port 14. In this process, the continuous turning of the first rotary furnace body 12 is conducive to promoting more uniform smoking between the biomass and the pyrolysis gas.

[0040] Furthermore, on the basis of the above embodiment, as shown in the figure, the first rotary furnace body 12 includes an inner furnace body 121 and an outer furnace body 122, and a condensation chamber 3 is provided between the inner furnace body 121 and the outer furnace body 122, wherein a heat conductive medium is introduced into the condensation chamber 3 to control the temperature of the fumigation furnace 1, and the heat conductive medium here can be low-temperature air, so that the cooling effect of the condensation chamber 3 promotes the condensation of pyrolysis gas into pyrolysis oil attached to the biomass, which is beneficial to improve the yield of biochar.

[0041] Preferably, the condensation chamber 3 can also be divided into a first condensation zone 31 and a second condensation zone 32. The temperature of the first condensation zone 31 is lower than that of the second condensation zone 32. The first condensation zone 31 is arranged on the side close to the first feed box 11, and the second condensation zone 32 is arranged on the side of the first discharge box 13. In this way, after the biomass enters the fumigation and roasting furnace 1, it gradually moves toward the side of the first discharge box 13 in the first rotary furnace body 12, and the pyrolysis gas flows toward the side of the first feed box 11 after entering the fumigation and roasting furnace 1, so that the pyrolysis gas and the biomass move toward each other and are in continuous contact. At this time, volatiles with different boiling points can be condensed due to different temperature ranges, thereby forming a graded condensation effect.

[0042] Specifically, the temperature of the second condensation zone 32 can be set in a medium-low or medium-high temperature range, for example: 80 degrees to 150 degrees, so as to condense the bio-oil that meets the temperature range, and then the pyrolysis gas after preliminary condensation is mixed with the biomass in the first condensation zone 31. The temperature of the first condensation zone 31 can be set between 20 degrees and 30 degrees, so as to condense the bio-oil that meets the range of 20 degrees to 30 degrees, and finally achieve the effect of graded condensation, so as to further facilitate the co-pyrolysis of bio-oil and biomass to prepare biochar, thereby improving the yield of biochar.

[0043] In some embodiments of the present invention, as shown in the figure, a scooping plate 4 is provided on the inner wall of the inner furnace body 121. Specifically, the biomass can be continuously scooped up and sprinkled through the scooping plate 4, thereby increasing the contact surface between the biomass and the pyrolysis gas, which is beneficial to the condensability of the volatile matter in the pyrolysis gas and condensing it on the biomass, thereby improving the yield of biochar.

[0044] Furthermore, on the basis of the above embodiment, a hollow heat conduction chamber 41 is provided in the material copying plate 4, and the heat conduction chamber 41 is connected to the condensation chamber 3, which is beneficial to improve the control of the condensation chamber 3 over the temperature of the inner area of ​​the furnace body and promote the condensation effect of condensable volatiles, so as to improve the fumigation effect between the pyrolysis gas and the biomass.

[0045] In some embodiments of the present invention, as shown in the figure, the system for preparing biochar by pyrolysis of fumigated biomass also includes a burner 5, wherein the burner 5 includes an air inlet 51 and an air outlet 52, the air inlet 51 is connected to the first air outlet 16, and the air outlet 52 is connected to the pyrolysis chamber. Specifically, there are still some condensable volatiles and non-condensable gases in the pyrolysis gas after condensation in the fumigation furnace 1, and this part of the pyrolysis gas can be introduced into the burner 5 for full combustion to generate high-temperature flue gas, and then the flue gas is introduced into the pyrolysis furnace 2. In this way, a large amount of heat contained in the flue gas can be used to supplement the energy consumption during pyrolysis, thereby achieving the effect of recovering part of the heat, reducing the energy consumption during pyrolysis, and improving energy utilization.

[0046] Preferably, since pyrolysis gas has requirements for its concentration and temperature during combustion, if it is used by directly igniting the pyrolysis gas, it is easily affected by the concentration and thus causes flameout, which in turn causes an adverse chain reaction. Therefore, the stability of solid fuel combustion can be used to ignite the pyrolysis gas, thereby achieving stable combustion of the pyrolysis gas.

[0047] Specifically, as shown in the figure, the burner 5 also includes a fuel inlet 53, a slag outlet 54 and a mesh partition 55. The mesh partition 55 is arranged above the air inlet 51, the fuel inlet 53 is arranged on the side wall of the burner 5 on one side of the mesh partition 55, and the slag outlet 54 is arranged on the side wall of the burner 5 on the other side of the mesh partition 55.

[0048] When in use, solid fuel enters the burner 5 through the fuel inlet 53 and burns on the mesh partition 55. When the pyrolysis gas enters the burner 5 through the air inlet 51, it is fully burned under the action of the flame at the mesh plate. In this way, no matter how the concentration of the pyrolysis gas changes, it will not affect the combustion of the pyrolysis gas when passing through the mesh partition 55, thereby effectively ensuring the stable operation of the entire system.

[0049] In some embodiments of the present invention, as shown in the figure, the pyrolysis furnace 2 includes: a second feed box 21, a second rotary furnace body 22 and a second discharge box 23, the two ends of the second rotary furnace body 22 are dynamically sealed and connected to the second feed box 21 and the second discharge box 23 respectively, the feed port 24 is provided on the second feed box 21, and the second air outlet 26 and the second discharge port 25 are provided on the second discharge box 23. When in use, the smoked and roasted biomass raw material enters from the second feed box 21 and continuously turns in the second rotary furnace, and finally moves to the second discharge box 23 and leaves through the second discharge port 25. In this process, the continuous turning of the second rotary furnace body 22 is conducive to making the biomass more evenly heated, improving the pyrolysis carbonization efficiency and the quality of biochar.

[0050] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0051] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example.

[0052] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A system for preparing biochar by pyrolysis of smoked biomass, characterized in that: include: A fumigation and roasting furnace, the fumigation and roasting furnace comprising a first material discharge port, a first air inlet port and a first air outlet port; A pyrolysis furnace, wherein a pyrolysis chamber is provided in the pyrolysis furnace, wherein the pyrolysis chamber is provided with a feed port, a second feed port and a second gas outlet, wherein the feed port is communicated with the first feed port, and the second gas outlet is communicated with the first gas inlet.

2. A system for preparing biochar by pyrolysis of smoked biomass according to claim 1, characterized in that: The smoking and roasting furnace includes: a first feed box, a first rotary furnace body and a first discharge box, the two ends of the first rotary furnace body are dynamically sealed and connected to the first feed box and the first discharge box respectively, the first discharge port and the first air inlet are arranged on the first discharge box, and the first air outlet is arranged on the first feed box.

3. A system for preparing biochar by pyrolysis of smoked biomass according to claim 2, characterized in that: The first rotary furnace body comprises an inner furnace body and an outer furnace body, and a condensation chamber is arranged between the inner furnace body and the outer furnace body.

4. A system for preparing biochar by pyrolysis of smoked biomass according to claim 3, characterized in that: The condensation chamber includes a first condensation zone and a second condensation zone. The temperature of the first condensation zone is lower than the temperature of the second condensation zone. The first condensation zone is arranged close to the first feed box, and the second condensation zone is arranged on the first discharge box.

5. The system for preparing biochar by pyrolysis of smoked biomass according to claim 3, characterized in that: A material-scraping plate is arranged on the inner side wall of the inner furnace body.

6. A system for preparing biochar by pyrolysis of smoked biomass according to claim 5, characterized in that: A hollow heat conduction chamber is arranged in the material copying plate, and the heat conduction chamber is communicated with the condensation chamber.

7. The system for preparing biochar by pyrolysis of smoked biomass according to claim 1, characterized in that: Also includes: A burner, the burner comprises an air inlet and an air outlet, the air inlet is communicated with the first air outlet, and the air outlet is communicated with the pyrolysis chamber.

8. The system for preparing biochar by pyrolysis of smoked biomass according to claim 2, characterized in that: The burner also includes: a fuel inlet, a slag outlet and a mesh partition, the mesh partition is arranged above the air inlet, the fuel inlet is arranged on the burner side wall on one side of the mesh partition, and the slag outlet is arranged on the burner side wall on the other side of the mesh partition.

9. The system for preparing biochar by pyrolysis of smoked biomass according to claim 1, characterized in that: The pyrolysis furnace includes: a second feed box, a second rotary furnace body and a second discharge box, the two ends of the second rotary furnace body are dynamically sealed and connected to the second feed box and the second discharge box respectively, the feed port is arranged on the second feed box, and the second air outlet and the second discharge port are arranged on the second discharge box.

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