Spiral pyrolysis device with multi-stage cam and pyrolysis method

Abstract

The present invention relates to the field of high-value utilization of organic solid waste, and specifically to a spiral pyrolysis device with a multi-stage cam, which includes a pyrolysis furnace, a rotating shaft, a multi-stage cam and a mixing blade. In addition, the present invention also proposes a pyrolysis method. Through the interaction between the inner surface of the rolling and grinding section of the pyrolysis furnace and the friction layer on the outer surface of the multi-stage cam, the rolling and crushing of raw materials such as fruit shell waste and sufficient contact with the catalyst are achieved, and the heat transfer and mass transfer effects are effectively enhanced. The raw material enters the rolling and grinding section, and continues to move forward in the constantly changing gap space between the surface of the multi-stage cam and the inner wall of the rolling and grinding section. Through the mutual extrusion and friction of the friction layer on the surface, efficient crushing pretreatment of fruit shell waste is achieved. After the crushed raw material is fully mixed with the catalyst, it enters the catalytic pyrolysis section of the pyrolysis furnace. The raw material is rapidly heated and catalytic pyrolysis occurs. Under the stirring and pushing action of the mixing blades, the raw material continues to move forward and is finally fully pyrolyzed.

Description

Technical Field

[0001] The invention relates to the field of high-value utilization of organic solid waste, and in particular to a spiral pyrolysis device with a multi-stage cam and a pyrolysis method. Background Art

[0002] my country has a very large planting area for economic forests. Every year, a large amount of residues such as fruit shells, pomace, and pruned branches and leaves are produced during the collection and processing process. The annual output of oil tea, walnut, and chestnut shells alone is more than 29.3 million tons. However, most of these organic fruit shell wastes are randomly discarded or incinerated, which not only pollutes the environment, but also causes a large waste of renewable carbon resources.

[0003] Pyrolysis is an efficient means of treating fruit shell waste. Compared with traditional treatment methods, it has the advantages of short treatment cycle, high conversion efficiency, and obvious volume reduction effect. At the same time, it can also obtain high-value solid, liquid, and gas products. It is a technology with great application and promotion prospects in the current harmless disposal and high-value utilization of fruit shell waste. The spiral pyrolysis reactor has the advantages of simple structure, precise control of reaction temperature, low wear of the device, and no need for additional carrier gas. It is the mainstream type of organic solid waste pyrolysis device. For example, Chinese invention patent CN101709224A discloses a spiral pyrolysis device for biomass waste, which uses conventional spiral blades to efficiently pyrolyze and liquefy raw materials such as sawdust into bio-oil at a pyrolysis temperature of 500 to 550°C. Unlike conventional biomass waste, fruit shell waste usually has a hard shell, and it is difficult to reduce the size of the raw material by collision. This will not only hinder the rotation of the spiral blades or even damage the blades, but also because the traditional pyrolysis device cannot effectively transfer heat and mass to them, the raw materials and the catalyst are difficult to fully contact, resulting in an insufficient pyrolysis process, very low oil yield, and severe carbonization. It is inevitable to use additional pretreatment equipment to deeply crush the hard shell in advance, which greatly increases the power consumption of the device and has poor technical and economic efficiency.

[0004] Therefore, it is urgent to develop a simple and efficient pyrolysis device for fruit shell waste, avoid complex pretreatment equipment, and improve the heat and mass transfer efficiency of the device, so as to achieve harmless disposal and high-value utilization of fruit shell waste. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a spiral pyrolysis device and a pyrolysis method with a multi-stage cam which can pre-deeply crush the hard shells, so as to solve the problems of low heat and mass transfer efficiency, severe blade wear, severe carbonization and high pretreatment cost in the treatment of fruit shell waste by the existing spiral pyrolysis device.

[0007] (II) Technical solution

[0008] In order to achieve the above object, the spiral pyrolysis device with a multi-stage cam of the present invention comprises:

[0009] A pyrolysis furnace, wherein the pyrolysis furnace is a hollow circular tube arranged obliquely, wherein the first end of the pyrolysis furnace is higher than the second end, a feed inlet is provided at the top of the first end of the pyrolysis furnace, a discharge outlet is provided at the bottom of the second end of the pyrolysis furnace, and an exhaust outlet is provided at the top of the second end of the pyrolysis furnace; a continuous crushing section and a catalytic pyrolysis section are formed in the pyrolysis furnace from the first end to the second end;

[0010] a rotating shaft, the rotating shaft being coaxially disposed in the pyrolysis furnace and being rotatable in the pyrolysis furnace, the rotating shaft extending from a first end to a second end of the pyrolysis furnace;

[0011] A multi-stage cam, each stage of the cam is an eccentric solid cylinder; the multi-stage cam is fixed on the rotating shaft in sequence from the first end to the second end of the rolling and grinding section, the thickness of the multi-stage cam gradually decreases and the bottom surface diameter gradually increases; the two adjacent stages of the cam fit each other and have opposite eccentric directions;

[0012] A mixing blade is fixed on the rotating shaft in the catalytic pyrolysis section.

[0013] Optionally, a friction layer is provided on the surface of the cam and the inner wall of the rolling and grinding section; the friction layer is a texture and / or a wear-resistant coating.

[0014] Optionally, a groove-shaped pyrolysis gas channel is provided on the inner wall at the top of the catalytic pyrolysis section, and the pyrolysis gas channel is directly connected to the exhaust port.

[0015] Optionally, the axial direction of the pyrolysis furnace forms an angle of 15 to 45 degrees with the horizontal direction.

[0016] Optionally, the mixing blade is a spiral blade coaxially arranged with the rotating shaft; the gap between the outer edge of the mixing blade and the inner wall of the pyrolysis furnace is 1 to 3 mm; and the pitch of the mixing blade is 30 to 100 mm.

[0017] Optionally, the bottom diameter of the first stage of the multi-stage cam is 1 to 1.2 times the diameter of the rotating shaft; the bottom diameter of the last stage of the multi-stage cam is 0.5 to 0.9 times the diameter of the mixing blade, and the thickness is 3 to 10 mm.

[0018] Optionally, a thermal insulation layer is arranged inside the furnace wall of the pyrolysis furnace.

[0019] Furthermore, the present invention also provides a pyrolysis method, which is implemented based on the above-mentioned spiral pyrolysis device with a multi-stage cam, and comprises the following steps:

[0020] S1, driving the rotating shaft to rotate, driving the multi-stage cam and the mixing blades to rotate at a set speed, and at the same time heating the crushing section and the catalytic pyrolysis section of the pyrolysis furnace to a set temperature respectively;

[0021] S2, adding raw materials and catalysts in a predetermined mass ratio from the feed port, and through the extrusion and friction between the surface of the cam and the inner wall of the rolling and grinding section, the raw materials are crushed and contacted with the catalyst in the rolling and grinding section;

[0022] S3. Under the action of gravity and friction, the mixture of raw materials and catalyst enters the catalytic pyrolysis section, the raw materials are heated and catalytic pyrolysis occurs;

[0023] S4, the pyrolysis gas generated in the catalytic pyrolysis section is discharged through the exhaust port, and then condensed and separated to obtain pyrolysis oil and non-condensable gas;

[0024] S5. The char generated after the raw material is completely pyrolyzed is discharged from the discharge port and collected under the combined action of the mixing blades and gravity.

[0025] Optionally, the set temperature of the rolling and grinding section is 100-200°C; the set temperature of the catalytic pyrolysis section is 400-600°C.

[0026] Optionally, the rotation speed of the rotating shaft is 5 to 15 r / min.

[0027] (III) Beneficial effects

[0028] The pyrolysis device and pyrolysis method provided by the technical solution of the present invention realize the crushing and full contact of raw materials such as fruit shell waste with the catalyst through the interaction between the inner surface of the crushing and grinding section of the pyrolysis furnace and the friction layer on the outer surface of the multi-stage cam, and effectively enhance the heat transfer and mass transfer efficiency. The raw material enters the crushing and grinding section in the pyrolysis furnace, and continues to move forward in the constantly changing gap space between each stage of the cam and the inner wall of the crushing and grinding section. Through the mutual extrusion and friction of the friction layer on the surface, the efficient crushing pretreatment of fruit shell waste is achieved. After the crushed raw material is fully mixed with the catalyst, it enters the catalytic pyrolysis section of the pyrolysis furnace. The raw material is rapidly heated and catalytic pyrolysis occurs. Under the stirring and pushing action of the mixing blades, the raw material continues to move forward and is finally fully pyrolyzed. Then, the generated pyrolysis gas is discharged after being converged through the pyrolysis gas channel, and then subjected to subsequent separation and condensation treatment, while the solid carbon and waste residue remaining from the pyrolysis are discharged under the action of the mixing blades and gravity and subjected to subsequent treatment.

[0029] The beneficial effects of the above technical solution of the present invention are as follows:

[0030] 1. High space utilization: No additional auxiliary pretreatment equipment is required, and the crushing section for raw material pretreatment and the catalytic pyrolysis section for pyrolysis are arranged in the same pyrolysis furnace. The device has a compact structure and improves space utilization.

[0031] 2. Strong adaptability to raw materials: A crushing device is added to the traditional spiral pyrolysis device, which can handle fruit shell waste with higher hardness. By replacing multi-stage cams with different numbers and sizes, precise crushing of specific fruit shell biomass can be achieved. It is also suitable for other organic solid waste raw materials with lower hardness.

[0032] 3. Efficient heat and mass transfer: Crushing fruit shell waste can effectively improve the degree of contact with the catalyst and enhance the heat and mass transfer effects.

[0033] 4. Segmented precise temperature control: Through segmented precise temperature control of the grinding and catalytic pyrolysis sections, the temperature conditions of the pretreatment and pyrolysis processes are made to conform to the optimal pyrolysis temperature of the pyrolysis curve as much as possible, thereby improving the pyrolysis conversion rate of the raw materials and the yield of the target product.

[0034] 5. Convenient reaction control: By controlling the feed rate, type and amount of catalyst, heating power, rotation speed of the rotating shaft, etc., the reaction temperature, reaction time, reaction mode and other conditions of different processes can be adjusted in time.

[0035] 6. Stable operation of the device: The crushing and grinding section pre-processes the hard fruit shell waste, making the mixing blades of the catalytic pyrolysis section less likely to be worn and stuck, which can ensure the smooth and continuous operation of the rotating mechanism.

[0036] 7. Long service life: The friction layer is a hard texture processed on the metal surface, or a wear-resistant coating can be set. It is easy to update and has low cost. At the same time, it can effectively reduce structural wear and extend service life.

[0037] 8. Automatic exhaust and pressure protection: In the catalytic pyrolysis section, the efficient pyrolysis of the raw materials causes the rapidly expanding pyrolysis gas to be collected through the pyrolysis gas channel above the pyrolysis furnace and discharged from the exhaust port, avoiding excessive pressure in the catalytic pyrolysis section that affects the pyrolysis reaction.

[0038] 9. Automatic slag discharge: The solid carbon and waste residue remaining from pyrolysis will be automatically discharged through the discharge port under the action of gravity and the pushing force of the mixing blades to prevent the pipeline in the pyrolysis furnace from being blocked.

[0039] 10. Effective dechlorination and clean emission: Pyrolysis is an anaerobic process that can produce reducing components such as H2 and CO, and the temperature is relatively low. It can effectively inhibit the generation of harmful substances such as dioxins from the source and achieve efficient dechlorination. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1It is a schematic structural diagram of a spiral pyrolysis device with a multi-stage cam according to the present invention.

[0041] [Description of Reference Numerals]

[0042] 1: pyrolysis furnace; Z1: rolling and grinding section; Z2: catalytic pyrolysis section; 11: feed inlet; 12: discharge outlet; 13: exhaust outlet; 14: insulation layer; 15: pyrolysis gas channel;

[0043] 2: Rotating shaft; 3: Cam; 4: Mixing blade; 5: Friction layer. DETAILED DESCRIPTION

[0044] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below through specific implementation modes in conjunction with the accompanying drawings.

[0045] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0046] In addition, in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0047] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; "connection" can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0048] See also Figure 1The present invention provides a spiral pyrolysis device with a multi-stage cam, which includes: a pyrolysis furnace 1, a rotating shaft 2, a multi-stage cam 3 and a mixing blade 4. The pyrolysis furnace 1 is a hollow circular tube arranged obliquely, and the first end of the pyrolysis furnace 1 is higher than the second end. A feed inlet 11 is provided at the top of the first end of the pyrolysis furnace 1 for feeding raw materials such as fruit shell waste, a discharge port 12 is provided at the bottom of the second end of the pyrolysis furnace 1 for the discharge of pyrolysis carbon, and an exhaust port 13 is provided at the top of the second end of the pyrolysis furnace 1 for the discharge of pyrolysis gas. Among them, the axial direction of the pyrolysis furnace 1 can preferably form an angle of 15 to 45° with the horizontal direction, so that the raw materials and catalyst can flow smoothly from the higher first end to the lower second end, but the flow speed will not be too fast to affect the pyrolysis reaction. Moreover, a continuous rolling and grinding section Z1 and a catalytic pyrolysis section Z2 are formed in the pyrolysis furnace 1 from the first end to the second end, that is, a section near the head end of the pyrolysis furnace 1 is the rolling and grinding section Z1, and a section near the end end is the catalytic pyrolysis section Z2, and the end of the rolling and grinding section Z1 and the head end of the catalytic pyrolysis section Z2 are connected to each other, wherein the rolling and grinding section Z1 and the catalytic pyrolysis section Z2 are respectively provided with independent heating mechanisms, such as electric heating pipes, so that segmented independent temperature control can be achieved. Through the segmented and precise temperature control of the rolling and grinding section Z1 and the catalytic pyrolysis section Z2, the temperature conditions of the pretreatment and pyrolysis process are made to meet the optimal pyrolysis temperature of the pyrolysis curve as much as possible, thereby improving the pyrolysis conversion rate of the raw materials and the yield of the target product. In addition, in order to further improve the heating efficiency and pyrolysis efficiency, an insulation layer 14 is also arranged in the furnace wall of the pyrolysis furnace 1 to prevent heat loss. Moreover, the crushing section Z1 and the catalytic pyrolysis section Z2 are continuously arranged in the pyrolysis furnace 1, eliminating the need for additional auxiliary pretreatment equipment. The crushing section Z1 for raw material pretreatment and the catalytic pyrolysis section Z2 for pyrolysis are arranged in the same pyrolysis furnace 1, making the device structure compact and improving space utilization.

[0049] The rotating shaft 2 is coaxially arranged in the pyrolysis furnace 1 and can rotate in the pyrolysis furnace 1. The rotating shaft 2 extends from the first end to the second end of the pyrolysis furnace 1. The rotating shaft 2 is rotatably supported by bearings on the end covers at both ends of the pyrolysis furnace 1, and is sealed at both ends of the pyrolysis furnace 1. Moreover, the rotating shaft 2 is driven by an external rotary driver. By controlling the feed rate, the type and amount of the catalyst, the heating power, the rotation speed of the rotating shaft 2, etc., the reaction temperature, reaction time, reaction mode and other conditions of different processes can be adjusted in time.

[0050] The multi-stage cam 3 can be divided into a first-stage cam, a second-stage cam, ... an N-stage cam (i.e., the last-stage cam), and each stage cam 3 is an eccentric solid cylinder (preferably an eccentric cylinder). The multi-stage cam 3 is fixed on the rotating shaft 2 in sequence from the first end to the second end of the rolling and grinding segment Z1 (the first-stage cam is close to the first end of the rolling and grinding segment Z1 and the last-stage cam is close to the second end of the rolling and grinding segment Z1), and the thickness of the multi-stage cam 3 gradually decreases and the bottom diameter gradually increases (for example, the thickness of the first-stage cam is greater than the thickness of the second-stage cam, and the bottom diameter of the first-stage cam is smaller than the bottom diameter of the second-stage cam). Moreover, the adjacent two-stage cams 3 fit each other and have opposite eccentric directions.

[0051] The multi-stage cam 3 arranged in this way can make the raw material continue to move forward in the constantly changing gap space between each stage cam 3 and the inner wall of the rolling and grinding section Z1 after entering the pyrolysis furnace 1, so as to achieve efficient crushing pretreatment of fruit shell waste. By adding a crushing device, fruit shell waste with higher hardness can be processed, and by replacing the multi-stage cam 3 with different numbers and sizes, the precise crushing of specific fruit shell biomass can be achieved, and it is also applicable to other organic solid waste raw materials with lower hardness. In addition, by using the gap between the multi-stage cam 3 and the inner wall of the rolling and grinding section Z1 to crush the fruit shell waste, it can effectively improve the full contact degree with the catalyst and enhance the heat transfer and mass transfer effects.

[0052] Also, see again Figure 1 The mixing blades 4 are fixed on the rotating shaft 2 in the catalytic pyrolysis section Z2. The solid carbon and waste residues left over from pyrolysis are automatically discharged through the discharge port 12 under the force of gravity and the pushing action of the mixing blades 4, thus preventing the pipeline in the pyrolysis furnace 1 from being blocked. The crushing and pretreatment of the hard shell waste by the rolling and grinding section Z1 makes the mixing blades 4 in the catalytic pyrolysis section less likely to be worn or stuck, thus ensuring the smooth and continuous operation of the rotating mechanism.

[0053] Moreover, in a preferred embodiment, a friction layer 5 may be provided on the surface of the cam 3 and the inner wall of the grinding and crushing section Z1. The friction layer 5 may be a hard cross pattern and / or a wear-resistant coating. According to actual needs, the friction layer 5 may be a pattern with a wear-resistant coating attached thereto, or may only be a pattern or only be a wear-resistant coating. The wear-resistant coating may be made of materials such as silicon carbide, aluminum oxide, and quartz, which is easy to update and has a low cost, and can effectively reduce structural wear and extend service life.

[0054] In addition, a groove-shaped pyrolysis gas channel 15 is provided on the inner wall at the top of the catalytic pyrolysis section Z2, and the pyrolysis gas channel 15 is directly connected to the exhaust port 13, so that the pyrolysis gas can be collected and flowed inside the pyrolysis furnace 1, and can also play a guiding role so that the pyrolysis gas can be discharged from the pyrolysis furnace 1 more quickly. In the catalytic pyrolysis section Z2, the pyrolysis gas that expands rapidly due to the efficient pyrolysis of the raw materials can be collected through the pyrolysis gas channel 15 above the pyrolysis furnace 1 and discharged from the exhaust port 13, so as to avoid excessive pressure in the catalytic pyrolysis section Z2 and affect the pyrolysis reaction.

[0055] Through the interaction between the inner surface of the crushing and grinding section Z1 of the pyrolysis furnace 1 and the friction layer 5 on the outer surface of the multi-stage cam 3, the crushing and full contact of the raw materials such as fruit shell waste with the catalyst are achieved, and the heat transfer and mass transfer effects are effectively enhanced. The raw material enters the crushing and grinding section Z1 of the pyrolysis furnace 1, and continues to move forward in the constantly changing gap space between each stage of the cam 3 and the inner wall of the crushing and grinding section Z1. Through the mutual extrusion and friction of the friction layer 5 on the surface, the efficient crushing pretreatment of the fruit shell waste is achieved. After the crushed raw material is fully mixed with the catalyst, it enters the catalytic pyrolysis section Z2 of the pyrolysis furnace 1. The raw material is rapidly heated and catalytically pyrolyzed. Under the stirring and pushing action of the mixing blades 4, the raw material continues to move forward and is finally fully pyrolyzed. Then, the generated pyrolysis gas is discharged after being gathered through the pyrolysis gas channel 15, and then subjected to subsequent separation and condensation treatment, while the solid carbon and waste residue remaining from the pyrolysis are discharged under the action of the mixing blades 4 and gravity and subjected to subsequent treatment. Pyrolysis is carried out in a closed pyrolysis furnace 1, which is an oxygen-free process and can produce reducing components such as H2 and CO, and the temperature is relatively low, which can effectively inhibit the generation of harmful substances such as dioxins from the source, and achieve efficient dechlorination. The pyrolysis device provided by the technical solution of the present invention has the characteristics of high space utilization, convenient reaction control, wide adaptability of raw materials, stable device operation, automatic exhaust, automatic slag discharge, etc., and can realize the efficient and continuous pyrolysis process of fruit shell waste that is difficult to handle by conventional pyrolysis methods, so that fruit shell waste is used at a high value.

[0056] In a more preferred embodiment, see again Figure 1, the mixing blade 4 is a spiral blade coaxially arranged with the rotating shaft 2. The diameter of the mixing blade 4 remains unchanged in the catalytic pyrolysis section Z2, and the gap between the outer edge of the mixing blade 4 and the inner wall of the pyrolysis furnace 1 (i.e., the circumferential inner surface of the pyrolysis furnace 1) is 1 to 3 mm, so that the material can be pushed smoothly to prevent the material from getting stuck. In addition, the pitch of the mixing blade 4 can be designed to be 30 to 100 mm according to actual needs. Further, in actual production, the bottom diameter of the first-stage cam in the multi-stage cam 3 can be 1 to 1.2 times the shaft diameter of the rotating shaft 2; the bottom diameter of the Nth-stage cam (i.e., the last-stage cam) in the multi-stage cam 3 can be 0.5 to 0.9 times the diameter of the mixing blade 4, and the thickness can be 3 to 10 mm. Such a clever setting can enable the multi-stage cam 3 to achieve optimal efficiency when crushing the raw materials.

[0057] Furthermore, the present invention also provides a pyrolysis method, which is implemented based on the above-mentioned spiral pyrolysis device with a multi-stage cam, and comprises the following steps:

[0058] S1, start the rotary driver to drive the rotating shaft 2 to rotate, drive the multi-stage cam 3 and the mixing blade 4 to rotate at a set speed, and at the same time heat the crushing section Z1 and the catalytic pyrolysis section Z2 of the pyrolysis furnace 1 to the set temperature respectively;

[0059] S2, adding fruit shell waste and other raw materials and catalysts in a predetermined mass ratio from the feed port 11, and through the extrusion and friction between the surface of the cam 3 and the inner wall of the rolling and grinding section Z1, the raw materials are crushed in the rolling and grinding section Z1, and the size of the raw materials gradually becomes smaller and fully contacts the catalyst;

[0060] S3, under the action of gravity and friction, the mixture of raw materials and catalyst enters the catalytic pyrolysis section Z2, the raw materials are rapidly heated and catalytic pyrolysis occurs;

[0061] S4, the pyrolysis gas generated in the catalytic pyrolysis section Z2 is gathered in the pyrolysis gas channel 15 and discharged through the exhaust port 13, and then condensed and separated to obtain pyrolysis oil and non-condensable gas;

[0062] S5. The char generated after the raw material is completely pyrolyzed is discharged from the discharge port 12 and collected under the combined action of the mixing blades 4 and gravity.

[0063] The raw material enters the crushing and grinding section Z1 of the pyrolysis furnace 1, and continues to move forward in the constantly changing gap space between the surface of the multi-stage cam 3 and the inner wall of the crushing and grinding section Z1. Through the mutual extrusion and friction of the friction layer 5 on the surface, efficient crushing pretreatment of the fruit shell waste is achieved. The above-mentioned pyrolysis method can realize the efficient and continuous pyrolysis process of fruit shell waste that is difficult to treat by conventional pyrolysis methods, so that the fruit shell waste is used in a high-value manner. Moreover, pyrolysis is an anaerobic process, which can produce reducing components such as H2 and CO, and the temperature is relatively low, which can effectively inhibit the generation of harmful substances such as dioxins from the source and achieve efficient dechlorination.

[0064] Among them, in order to improve the catalytic pyrolysis efficiency of the raw materials, the set temperature of the rolling and grinding section Z1 is 100-200°C; the set temperature of the catalytic pyrolysis section Z2 is 400-600°C. Through the segmented and precise temperature control of the rolling and grinding section Z1 and the catalytic pyrolysis section Z2, the temperature conditions of the pretreatment and pyrolysis process are made to conform to the optimal pyrolysis temperature of the pyrolysis curve as much as possible, thereby improving the pyrolysis conversion rate of the raw materials and the yield of the target product. In addition, the rotation speed of the rotating shaft 2 can also be set to 5-15r / min accordingly. By controlling the feed rate, the type and amount of the catalyst, the heating power, the rotation speed of the rotating shaft 2, etc., the reaction temperature, reaction time, reaction mode and other conditions of different processes can be adjusted in time.

[0065] The following is a detailed description of the process flow of pyrolysis using a spiral pyrolysis device with a multi-stage cam through specific embodiments, and each embodiment uses a device with basically the same structure.

[0066] Example 1

[0067] The inner diameter of the pyrolysis furnace 1 is 300mm, the length of the crushing section Z1 of the pyrolysis furnace 1 is 540mm, and the length of the catalytic pyrolysis section Z2 is 1000mm; the diameter of the rotating shaft 2 is 100mm; the cam 3 has eighteen levels, and the diameter of the multi-level cam gradually increases from 120mm at the first level to 260mm at the eighteenth level, and the thickness decreases from 55mm at the first level to 5mm at the eighteenth level; the outer diameter of the mixing blade 4 is 296mm, the distance between the edge of the mixing blade 4 and the inner wall of the pyrolysis furnace 1 is 2mm, and the pitch of the mixing blade 4 is 50mm.

[0068] Walnut shell raw materials with an average particle size of 20 mm are mixed with activated carbon catalyst and sent to pyrolysis furnace 1. The temperature of the crushing section Z1 is set to 100°C, and the speed of the rotating shaft 2 is 10r / min. After the raw materials are crushed, the average particle size is reduced to 3mm. Then the raw materials are sent to the catalytic pyrolysis section Z2 with a temperature set to 450°C. Under the stirring and pushing of the mixing blade 4, the raw materials are rapidly heated and pyrolysis reaction occurs. The pyrolysis gas is collected and quickly separated and condensed. The liquid phase yield is 55.8wt%. Phenolic substances in bio-oil account for 68.5% of the detectable organic components, of which phenol accounts for 33.7%, realizing the high-value utilization of walnut shell waste.

[0069] Example 2

[0070] The present embodiment differs from the first embodiment in that the structure of the multi-stage cam 3 is changed. The cam 3 has fifteen stages, and the diameter of the cam 3 gradually increases from 120 mm at the first stage to 240 mm at the fifteenth stage, while the thickness decreases from 64 mm at the first stage to 8 mm at the fifteenth stage.

[0071] The coconut shell raw material with an average particle size of 30 mm was mixed with K2CO3 catalyst and sent to the pyrolysis furnace 1. The temperature of the grinding section Z1 was set to 200°C and the speed of the rotating shaft 2 was 5r / min. After the raw material was crushed, the average particle size was reduced to 10 mm. Then the raw material was sent to the catalytic pyrolysis section Z2 with a temperature set to 600°C. Under the stirring and pushing of the mixing blade 4, the temperature was rapidly increased and the pyrolysis reaction occurred. The solid product remaining from the pyrolysis was collected, and the solid phase yield was 45.5wt%. Finally, the specific surface area of ​​1798.3cm 2 / g, pore size distribution of 2 to 50nm, and mesoporous activated carbon have achieved high-value utilization of coconut shell waste.

[0072] Example 3

[0073] The difference between this embodiment and embodiment 1 is that the pitch of the mixing blade 4 is 30 mm.

[0074] The camellia oleifera shell raw material with an average particle size of 20 mm was mixed with a zinc chloride catalyst and sent to the pyrolysis furnace 1. The temperature of the crushing section Z1 was set to 100°C, and the speed of the rotating shaft 2 was 5r / min. The raw material was crushed, and the average particle size was reduced to 5 mm. Then the raw material was sent to the catalytic pyrolysis section Z2 with a temperature set to 400°C. Under the stirring and pushing of the mixing blade 4, the temperature gradually increased and a pyrolysis reaction occurred. The pyrolysis gas was collected and quickly separated and condensed. The yield of the liquid product was 53.8wt%, and the target product furfural accounted for 21.9% of the liquid product, realizing the high-value utilization of camellia oleifera shell waste.

[0075] Example 4

[0076] The difference between this embodiment and embodiment 1 is that the pitch of the mixing blade 4 is 100 mm.

[0077] The chestnut shells with an average particle size of 20 mm were fed into the pyrolysis furnace 1. The temperature of the crushing section Z1 was set to 200°C and the speed of the rotating shaft 2 was 5 r / min. The raw materials were crushed and the average particle size was reduced to 2 mm. Then the raw materials were fed into the catalytic pyrolysis section Z2 with a temperature set to 500°C. Under the stirring and pushing of the mixing blades 4, the temperature gradually increased and pyrolysis occurred. The combustible pyrolysis gas was collected, and the gas yield reached 63.7wt% and the average calorific value reached 13.6MJ / m 3 , realizing the high-value utilization of chestnut shell waste.

[0078] It should be understood that the above description of the specific embodiments of the present invention is only for illustrating the technical route and features of the present invention, and its purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly, but the present invention is not limited to the above specific implementation methods. Any changes or modifications made within the scope of the claims of the present invention should be included in the protection scope of the present invention.

Claims

1. A spiral pyrolysis device with a multi-stage cam, characterized in that: include: A pyrolysis furnace (1), wherein the pyrolysis furnace (1) is a hollow circular tube arranged obliquely, the first end of the pyrolysis furnace (1) is higher than the second end, a feed inlet (11) is provided at the top of the first end of the pyrolysis furnace (1), a discharge outlet (12) is provided at the bottom of the second end of the pyrolysis furnace (1), and an exhaust outlet (13) is provided at the top of the second end of the pyrolysis furnace (1); a continuous crushing section (Z1) and a catalytic pyrolysis section (Z2) are formed in the pyrolysis furnace (1) from the first end to the second end; a rotating shaft (2), the rotating shaft (2) being coaxially arranged in the pyrolysis furnace (1) and being capable of rotating in the pyrolysis furnace (1), the rotating shaft (2) extending from a first end to a second end of the pyrolysis furnace (1); A multi-stage cam (3), each stage of the cam (3) is an eccentric solid cylinder; the multi-stage cam (3) is fixed to the rotating shaft (2) in sequence from the first end to the second end of the rolling and grinding section (Z1); the thickness of the multi-stage cam (3) gradually decreases and the bottom surface diameter gradually increases; two adjacent stages of the cam (3) fit each other and have opposite eccentric directions; A mixing blade (4), wherein the mixing blade (4) is fixed on the rotating shaft (2) in the catalytic pyrolysis section (Z2).

2. The spiral pyrolysis device with a multi-stage cam according to claim 1, characterized in that: The axial direction of the pyrolysis furnace (1) forms an angle of 15 to 45 degrees with the horizontal direction.

3. The spiral pyrolysis device with a multi-stage cam according to claim 1, characterized in that: A friction layer (5) is provided on the surface of the cam (3) and the inner wall of the rolling and grinding section (Z1); the friction layer (5) is a texture and / or a wear-resistant coating.

4. The spiral pyrolysis device with a multi-stage cam according to claim 1, characterized in that: A groove-shaped pyrolysis gas channel (15) is provided on the inner wall at the top of the catalytic pyrolysis section (Z2), and the pyrolysis gas channel (15) is directly connected to the exhaust port (13).

5. The spiral pyrolysis device with a multi-stage cam according to any one of claims 1 to 4, characterized in that: The mixing blade (4) is a spiral blade coaxially arranged with the rotating shaft (2); the gap between the outer edge of the mixing blade (4) and the inner wall of the pyrolysis furnace (1) is 1 to 3 mm; and the pitch of the mixing blade (4) is 30 to 100 mm.

6. The spiral pyrolysis device with a multi-stage cam according to any one of claims 1 to 4, characterized in that: The bottom diameter of the first stage of the multi-stage cam (3) is 1 to 1.2 times the diameter of the rotating shaft (2); the bottom diameter of the last stage of the multi-stage cam (3) is 0.5 to 0.9 times the diameter of the mixing blade (4), and the thickness is 3 to 10 mm.

7. The spiral pyrolysis device with a multi-stage cam according to any one of claims 1 to 4, characterized in that: A thermal insulation layer (14) is arranged inside the furnace wall of the pyrolysis furnace (1).

8. A pyrolysis method, which is implemented based on the spiral pyrolysis device with multi-stage cams according to any one of claims 1 to 7, characterized in that: The pyrolysis method comprises the following steps: S1, driving the rotating shaft (2) to rotate, driving the multi-stage cam (3) and the mixing blades (4) to rotate at a set speed, and at the same time heating the crushing section (Z1) and the catalytic pyrolysis section (Z2) of the pyrolysis furnace (1) to set temperatures respectively; S2, adding raw materials and catalyst in a predetermined mass ratio from the feed port (11), and through the extrusion and friction between the surface of the cam (3) and the inner wall of the rolling and grinding section (Z1), the raw materials are crushed and brought into contact with the catalyst in the rolling and grinding section (Z1); S3. Under the action of gravity and friction, the mixture of raw materials and catalyst enters the catalytic pyrolysis section (Z2), the raw materials are heated and catalytic pyrolysis occurs; S4, the pyrolysis gas generated in the catalytic pyrolysis section (Z2) is discharged through the exhaust port (13), and then condensed and separated to obtain pyrolysis oil and non-condensable gas; S5. The char generated after the raw material is completely pyrolyzed is discharged from the discharge port (12) and collected under the combined action of the mixing blades (4) and gravity.

9. The pyrolysis method according to claim 8, characterized in that The set temperature of the rolling and grinding section (Z1) is 100-200°C; the set temperature of the catalytic pyrolysis section (Z2) is 400-600°C.

10. The pyrolysis method according to claim 8, characterized in that: The rotation speed of the rotating shaft (2) is 5-15 r / min.

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