A carbonization device and system for preparing biochar by co-pyrolysis of bio-oil and biomass

Abstract

The application discloses a carbonization device for preparing biochar by co-pyrolysis of bio-oil and biomass, which comprises a feeding tank, a furnace body and a discharging tank, wherein one end of the furnace body is connected with the feeding tank in a dynamic sealing mode, the other end of the furnace body is connected with the discharging tank in a dynamic sealing mode, the furnace body is a rotary furnace body, the furnace body comprises a first shell and a second shell, a part of cavities between the first shell and the second shell is arranged as a heating cavity, and the other part of cavities is arranged as a condensing cavity; the temperature of corresponding sections can be controlled by heat-conducting media introduced into the condensing cavity and the heating cavity. Thus, the application can condense pyrolysis gas generated during pyrolysis of biomass to form pyrolysis oil, and use the biomass itself as one of condensing media, so that the condensed bio-oil is wrapped on the biomass, thereby realizing co-pyrolysis of bio-oil and biomass for carbon fixation, and further utilizing the co-pyrolysis effect to seal more carbon elements in biochar, so as to improve the yield of biochar.

Description

Technical Field

[0001] This invention relates to the field of biomass pyrolysis technology, and in particular to a pyrolysis carbonization apparatus and system for preparing biochar through co-pyrolysis. Background Technology

[0002] Biomass energy is a widely distributed renewable energy source that is carbon neutral and can balance CO2 emissions and absorption. 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 lead to a series of problems that restrict its wider application, such as difficult transportation, high cost, and seasonal limitations.

[0003] Pyrolysis, as a biomass processing and fuel upgrading technology, can improve the properties of raw materials and produce energy and chemical products. Pyrolysis typically converts biomass into gaseous, liquid, and solid three-phase products, and the yield of these products is controlled by altering pyrolysis process parameters, such as pyrolysis temperature, heating rate, and carrier gas flow rate. Among these three-phase products, biochar, due to its excellent fuel characteristics (high energy density, high calorific value, high carbon content, and low oxygen content), is the most promising alternative to coal.

[0004] In traditional biomass pyrolysis processes, most of the carbon is transferred to bio-oil and pyrolysis gas, resulting in low biochar yield. The resulting biochar fuel has limitations in yield, carbon retention, and combustion performance, leading to poor economic viability. Increasing the biochar yield and carbon content allows for the sequestration of more carbon elements within the biochar, which is crucial for achieving green and sustainable development.

[0005] Currently, there are two main methods for carbon fixation in biomass pyrolysis. One is to use pressure equipment to increase the reaction pressure during the biomass pyrolysis process. However, pressurized pyrolysis is usually intermittent, which cannot meet the requirements of 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 method is to use additives mixed with biomass for pyrolysis. However, the use of additives will increase the industrial production cost, and the addition of additives will change the composition of biomass pyrolysis products, which may affect the subsequent utilization value of the pyrolysis products. In addition, some additives may cause environmental pollution. Summary of the Invention

[0006] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a carbonization device for preparing biochar by co-pyrolysis of bio-oil and biomass. This device can realize in-situ continuous atmospheric pressure carbonization, and coordinate the pyrolysis between bio-oil and biomass, thereby encapsulating more carbon elements in the biomass in the biochar.

[0007] A carbonization apparatus for preparing biochar by co-pyrolysis of bio-oil and biomass according to an embodiment of the present invention includes: A feeding box, wherein the feeding box is provided with a first feeding port and an air outlet; The furnace body has one end dynamically sealed to the feed box. The furnace body includes a first shell and a second shell. A portion of the cavity between the first shell and the second shell is set as a heating chamber, and another portion of the cavity is set as a condensing chamber. The condensing chamber is located on the side close to the first feed inlet, and the heating chamber is located on the side away from the first feed inlet. The discharge box is dynamically sealed to the other end of the furnace body, and the bottom of the discharge box is provided with a first discharge port.

[0008] 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 located near the gas outlet, and the second condensation zone is located between the first condensation zone and the heating chamber.

[0009] According to some embodiments of the present invention, a material-lifting plate is provided on the inner sidewall of the first housing.

[0010] According to some embodiments of the present invention, the lifting plate includes a first lifting plate unit, and a plurality of first lifting plate units are axially spaced along the inner wall of the furnace body corresponding to the condensation cavity. Each first lifting plate unit includes a first lifting plate, which is distributed circumferentially along the inner wall of the furnace body. The first lifting plates of adjacent first lifting plate units are staggered. The lifting plate includes a second lifting plate unit. Multiple second lifting plate units are axially spaced along the inner wall of the furnace corresponding to the heating chamber. Each second lifting plate unit includes a second lifting plate. The second lifting plates are distributed circumferentially along the inner wall of the furnace body, and the second lifting plates of adjacent second lifting plate units are staggered.

[0011] According to some embodiments of the present invention, the first heat transfer plate is provided with a hollow first heat transfer cavity, which is in communication with the condensation cavity; and / or The second heat transfer plate has a hollow second heat transfer cavity, which is connected to the heating cavity.

[0012] According to some embodiments of the present invention, a hopper and a feeding device are also included, one end of the feeding device being connected to the hopper and the other end being connected to the first feed inlet.

[0013] In some embodiments of the present invention, the feeding device is a screw feeder.

[0014] A carbonization system for preparing biochar by co-pyrolysis of bio-oil and biomass according to another embodiment of the present invention includes: A drying oven, the drying oven including a second inlet and a second outlet; A carbonization furnace, wherein the carbonization furnace employs the carbonization apparatus as described in any one of claims 1 to 7, and the first feed inlet is connected to the second discharge outlet.

[0015] According to some embodiments of the present invention, the combustion furnace further includes an air inlet and an air outlet, the air inlet being connected to the air outlet and the air outlet being connected to the heating chamber.

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

[0017] Beneficial effects

[0018] This invention utilizes the pyrolysis gas generated during biomass pyrolysis to condense and form pyrolysis oil, and uses the biomass itself as one of the condensation media to coat the biomass with the condensed bio-oil, thereby achieving synergistic pyrolysis and carbon fixation of bio-oil and biomass. Furthermore, this synergistic pyrolysis effect allows more carbon elements to be sealed in biochar, thereby increasing the yield of biochar.

[0019] Furthermore, this application essentially combines the traditional condensation device and carbonization device into one, integrating the condensation function into the carbonization device to achieve in-situ condensation. This greatly simplifies the operation process of co-pyrolysis of bio-oil and biomass, eliminating the need for manual collection of condensed oil and the need for mixing bio-condensed oil with biomass before pyrolysis. Therefore, it can achieve in-situ continuous co-pyrolysis charcoal production, which not only improves the yield of charcoal production but also enhances the efficiency of charcoal production. Attached Figure Description

[0020] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of a carbonization system according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the carbonization apparatus according to an embodiment of the present invention; Figure 3 This is a schematic cross-sectional view of the furnace body according to an embodiment of the present invention. Figure 1 ; Figure 4 This is a schematic cross-sectional view of the furnace body according to an embodiment of the present invention. Figure 2 .

[0021] Figure label: 100. Carbonization device; 200. Carbonization system; 1. Feed box; 11. First feed inlet; 12. Air outlet; 2. Furnace body; 21. First shell; 22. Second shell; 23. Condensation chamber; 231. First condensation zone; 232. Second condensation zone; 24. Heating chamber; 3. Discharge box; 31. First discharge outlet; 4. Lifting plate; 41. First lifting plate; 42. Second lifting plate; 43. First heat transfer chamber; 44. Second heat transfer chamber; 51. Hopper; 52. Feeding device; 6. Drying furnace; 61. Second feed inlet; 62. Second discharge outlet; 7. Combustion furnace; 71. Air inlet; 72. Air outlet; 73. Fuel inlet; 74. Slag outlet; 75. Mesh plate. Detailed Implementation

[0022] The technical solutions of the embodiments disclosed in this application will be clearly and completely described below with reference to the accompanying drawings. The descriptions of the embodiments are merely illustrative and exemplary, and are not intended to limit the scope of this disclosure or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without inventive effort should fall within the scope of protection of this disclosure. Furthermore, techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification.

[0023] Combination Figures 1 to 4 As shown, a carbonization apparatus 100 for preparing biochar by co-pyrolysis of bio-oil and biomass according to an embodiment of the present invention includes at least: a feed box 1, a furnace body 2, and a discharge box 3. One end of the furnace body 2 is dynamically sealed to the feed box 1, and the other end is dynamically sealed to the discharge box 3. The feed box 1 is provided with a first feed inlet 11 and an air outlet 12. The bottom of the discharge box 3 is provided with a first discharge outlet 31. The furnace body 2 is a rotary furnace body 2, which includes a first shell 21 and a second shell 22. A portion of the cavity between the first shell 21 and the second shell 22 is set as a heating chamber 24, and another portion of the cavity is set as a condensing chamber 23. The condensing chamber 23 is located on the side close to the first feed inlet 11, and the heating chamber 24 is located on the side away from the first feed inlet 11. Specifically, the temperature of the corresponding section can be controlled by the heat-conducting medium introduced into the condensing chamber 23 and the heating chamber 24. The condensing chamber can use room temperature air or coolant as the cooling medium, and the heating chamber can use heat-conducting oil or high temperature air as the heating medium.

[0024] In use, biomass pellets enter the furnace body 2 through the first feed inlet 11 and undergo pyrolysis in the heating chamber 24 section of the furnace body 2. While producing biochar, a large amount of gaseous products are also generated during pyrolysis. The pyrolyzed biochar is discharged through the first feed inlet 11, and the generated gaseous products move towards the outlet 12. The condensable volatiles in the gaseous products will condense into bio-oil in the condensation chamber 23 section of the furnace body 2 and adhere to and coat the biomass. Subsequently, the bio-oil and biomass are synergistically pyrolyzed in the heating chamber 24 section to achieve carbon fixation.

[0025] Therefore, this device can utilize the synergistic pyrolysis of bio-oil and biomass to encapsulate more carbon elements in biochar, thereby increasing the biochar yield. Specifically, during the co-pyrolysis process, the presence of bio-oil distillation residue fills part of the porous structure of the biochar, thus limiting the escape of primary biomass pyrolysis products and retaining them in the carbon matrix. The free radicals (such as phenoxy groups) in these primary pyrolysis products can crosslink with hemicellulose and cellulose, undergoing further condensation polymerization reactions, ultimately promoting the formation of stable biochar. At this point, the condensed bio-oil can act as a carbon fixation agent.

[0026] The high carbon retention rate in biochar is beneficial for improving the 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 that of fossil fuels.

[0027] Furthermore, this application essentially combines the traditional condensation device and carbonization device into one, integrating the condensation function into the carbonization device to achieve in-situ condensation. This greatly simplifies the operation process of co-pyrolysis of bio-oil and biomass, eliminating the need for manual collection of condensed oil and the need to collect bio-condensed oil separately before mixing and pyrolysis with biomass. Therefore, it can improve the mixing efficiency between bio-oil and biomass, greatly reduce the transmission loss of bio-oil in the device pipeline, and achieve the effect of efficient and continuous co-pyrolysis char production. This not only increases the yield of char production but also improves the efficiency of char production.

[0028] Furthermore, based on the above embodiments, such as Figure 2As shown, the condensation chamber 23 also includes a first condensation zone 231 and a second condensation zone 232. The temperature of the first condensation zone 231 is lower than that of the second condensation zone 232. The first condensation zone 231 is located near the gas outlet 12, and the second condensation zone 232 is located between the first condensation zone 231 and the heating chamber 24. Specifically, dividing the condensation chamber into zones facilitates the formation of a staged condensation effect. Since the organic compounds in the biomass pyrolysis gas have different boiling points, different temperature ranges can be used to stage-wise condense organic compounds with different boiling points, thereby increasing the total yield of bio-oil. This is beneficial for the co-pyrolysis of bio-oil and biomass to produce biochar, thus increasing the biochar yield.

[0029] In some embodiments of the present invention, such as Figure 2 and Figure 3 As shown, a lifting plate 4 is provided on the inner wall of the first shell 21. When the lifting plate 4 is placed in the area of ​​the furnace body 2 corresponding to the heating chamber 24, the biomass is continuously turned over by the lifting plate 4, so that the biomass pyrolysis is more uniform and the quality of biochar production is improved.

[0030] When the lifting plate 4 is set in the area inside the furnace body 2 corresponding to the condensation chamber 23, the biomass can be lifted and scattered by the lifting plate 4, thereby increasing the contact area between the biomass and the biomass pyrolysis gas. This is beneficial for the condensable volatiles in the pyrolysis gas to condense and coat the biomass, thereby increasing the yield of biochar.

[0031] Furthermore, based on the above embodiments, such as Figure 3 As shown, the lifting plate 4 includes a first lifting plate 41 unit. Multiple first lifting plate 41 units are axially spaced along the inner wall of the furnace body 2 corresponding to the condensation chamber 23. Each first lifting plate 41 unit includes a first lifting plate 41, which is distributed circumferentially along the inner wall of the furnace body 2. The first lifting plates 41 of adjacent first lifting plate 41 units are staggered. This helps to form multiple sprinkling surfaces, thereby further increasing the contact area between biomass pellets and pyrolysis gas.

[0032] Similarly, the lifting plate 4 may also include a second lifting plate 42 unit. Multiple second lifting plate 42 units are axially spaced along the inner wall of the furnace body 2 corresponding to the heating chamber 24. Each second lifting plate 42 unit includes a second lifting plate 42, which is distributed circumferentially along the inner wall of the furnace body 2. The second lifting plates 42 of adjacent second lifting plate 42 units are staggered, which helps to form multiple sprinkling surfaces, making the biomass pellets more uniformly heated and improving the quality of biomass pyrolysis.

[0033] Preferably, based on the above embodiments, such as Figure 4As shown, the first lifting plate 41 is provided with a hollow first heat transfer cavity 43, which is connected to the condensation cavity 23. This helps to maintain the heat transfer effect between the first heat transfer cavity 43 and the condensation cavity 23, reduces the temperature effect of biomass pyrolysis gas on the temperature of the first lifting plate 41, and thus improves the condensation effect of condensable volatiles between the first lifting plate 41 and biomass.

[0034] Similarly, the second heat transfer plate 42 is also provided with a hollow second heat transfer cavity 44, which can be connected to the heating cavity 24. This is conducive to the transfer of heat from the heating cavity 24 to the biomass, thereby improving the pyrolysis efficiency of the biomass.

[0035] In some embodiments of the present invention, such as Figure 1 As shown, the carbonization device also includes a hopper 51 and a feeding device 52. One end of the feeding device 52 is connected to the hopper 51, and the other end is connected to the feed inlet. Specifically, the combination of the hopper 51 and the feeding device 52 can better control the conveying rate of biomass raw materials, thereby more accurately controlling the amount of feed per unit time, and thus controlling the reaction balance of biomass and bio-oil in the carbonization device, and improving the yield of biochar.

[0036] Preferably, the feeding device 52 can be a screw feeder, which helps to improve the overall sealing of the carbonization device, prevent the pyrolysis gas from escaping at will, and avoid affecting the condensation effect of condensable volatiles and operational safety.

[0037] Another embodiment of the present invention provides a carbonization system 200 for preparing biochar through co-pyrolysis of bio-oil and biomass, comprising at least a drying furnace 6 and a carbonization furnace. The drying furnace 6 includes a second feed inlet 61 and a second discharge outlet 62. The carbonization furnace employs any of the carbonization devices described in the above embodiments. Specifically, the first feed inlet 11 is connected to the second discharge outlet 62. The biomass raw material enters the drying furnace 6 through the second feed inlet 61, undergoes pre-drying within the drying furnace 6, and then exits through the second discharge outlet 62. This pre-drying process reduces the moisture content of the biomass in advance, thereby improving the carbonization efficiency during biomass pyrolysis.

[0038] Furthermore, based on the above embodiments, such as Figure 1As shown, the carbonization system 200 also includes a combustion furnace 7, which includes an air inlet 71 and an air outlet 72. The air inlet 71 is connected to the air outlet 12, and the air outlet 72 is connected to the heating chamber 24. In use, the condensed pyrolysis gas leaves the carbonization device through the air outlet 12 and then enters the combustion furnace 7 through the air inlet 71 for complete combustion. The combustion produces high-temperature flue gas, which is then introduced into the heating chamber 24 of the carbonization device. This allows the large amount of heat contained in the flue gas to supplement the energy consumption of the pyrolysis device, thereby achieving the effect of recovering some heat, reducing energy consumption during pyrolysis, and improving energy utilization.

[0039] Furthermore, since the concentration and temperature of pyrolysis gas are required during combustion, if the pyrolysis gas is used by direct ignition, it is easily affected by the concentration, which may lead to flameout and cause adverse chain reactions. Therefore, the stability of solid fuel combustion can be used to ignite the pyrolysis gas, thereby achieving stable combustion of the pyrolysis gas.

[0040] Specifically, such as Figure 1 As shown, the combustion furnace 7 also includes a fuel inlet 73, a slag outlet 74, and a mesh partition. The mesh partition is located above the air inlet 71, the fuel inlet 73 is located on one side of the combustion furnace 7 sidewall of the mesh partition, and the slag outlet 74 is located on the other side of the combustion furnace 7 sidewall of the mesh partition.

[0041] In use, solid fuel is introduced into the combustion furnace 7 through fuel inlet 73 and burned on the mesh partition. When the pyrolysis gas enters the combustion furnace 7 through air inlet 71, it is fully burned by the flame at the mesh plate 75. In this way, no matter how the concentration of the pyrolysis gas changes, it will not affect the combustion of the pyrolysis gas when it passes through the mesh partition, thus effectively ensuring the stable operation of the system.

[0042] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0043] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example.

[0044] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A carbonization apparatus for preparing biochar by co-pyrolysis of bio-oil and biomass, characterized in that, include: A feeding box, wherein the feeding box is provided with a first feeding port and an air outlet; The furnace body has one end dynamically sealed to the feed box. The furnace body includes a first shell and a second shell. A portion of the cavity between the first and second shells is a heating chamber, and another portion is a condensing chamber. The condensing chamber is located near the first feed inlet, and the heating chamber is located away from the first feed inlet. The condensing chamber includes a first condensing zone and a second condensing zone. The temperature of the first condensing zone is lower than the temperature of the second condensing zone. The first condensing zone is located near the air outlet, and the second condensing zone is located between the first condensing zone and the heating chamber. A lifting plate is provided on the inner wall of the first shell. The lifting plate includes a first lifting plate unit, and multiple first lifting plate units are positioned along the condensing chamber... The first lifting plate unit includes a first lifting plate, which is distributed circumferentially along the inner wall of the furnace body. The first lifting plates of adjacent first lifting plate units are staggered. The first lifting plate has a hollow first heat transfer cavity, which is connected to the condensation cavity. The second lifting plate also includes a second lifting plate unit, which is distributed circumferentially along the inner wall of the furnace body corresponding to the heating cavity. The second lifting plate unit includes a second lifting plate, which is distributed circumferentially along the inner wall of the furnace body. The second lifting plates of adjacent second lifting plate units are staggered. The second lifting plate has a hollow second heat transfer cavity, which is connected to the heating cavity. The discharge box is dynamically sealed to the other end of the furnace body, and the bottom of the discharge box is provided with a first discharge port.

2. The carbonization apparatus for preparing biochar by co-pyrolysis of bio-oil and biomass according to claim 1, characterized in that, It also includes a hopper and a feeding device, one end of which is connected to the hopper and the other end of which is connected to the first feed inlet.

3. The carbonization apparatus for preparing biochar by co-pyrolysis of bio-oil and biomass according to claim 2, characterized in that, The feeding device is a screw feeder.

4. A carbonization system for preparing biochar by co-pyrolysis of bio-oil and biomass, characterized in that, include: A drying oven, the drying oven including a second inlet and a second outlet; A carbonization furnace, wherein the carbonization furnace employs the carbonization apparatus as described in any one of claims 1 to 3, and the first feed inlet is connected to the second discharge outlet.

5. The carbonization system for preparing biochar by co-pyrolysis of bio-oil and biomass according to claim 4, characterized in that, Also includes: A combustion furnace, comprising an air inlet and an air outlet, wherein the air inlet is connected to the air outlet and the air outlet is connected to the heating chamber.

6. The carbonization system for preparing biochar by co-pyrolysis of bio-oil and biomass according to claim 5, characterized in that, The combustion furnace further includes a fuel inlet, a slag outlet, and a mesh partition. The mesh partition is located above the air inlet, the fuel inlet is located on one side of the combustion furnace sidewall of the mesh partition, and the slag outlet is located on the other side of the combustion furnace sidewall of the mesh partition.

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