Spiral pyrolysis device with concave pressure roller 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 concave pressure roller, which includes a furnace body, a rotating shaft, a concave pressure roller and a stirring blade. In addition, the present invention also proposes a pyrolysis method. Through the interaction between the inner surface of the crushing section of the furnace body and the friction layer on the outer surface of the concave pressure roller, the crushing and sufficient contact of 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 furnace body crushing section of the pyrolysis device, and continues to move forward in the gap space that is constantly shrinking between the groove of the concave pressure roller and the inner wall of the crushing 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 reaction section of the furnace body, the raw material is rapidly heated and catalytic pyrolysis occurs, and the raw material is stirred and pushed by the stirring blade, and 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 concave pressure roller and a pyrolysis method. Background Art

[0002] Every year, during the collection and processing of economic forests, a large amount of residues such as fruit shells, fruit residues, and pruned branches and leaves are generated. If these organic fruit shell wastes are discarded or burned at will, it will not only pollute the environment, but also cause a large amount of 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 CN1 01709224A 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 500N550℃. 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 concave pressure roller capable of pre-deeply crushing the hard shell.

[0007] (II) Technical solution

[0008] In order to achieve the above object, the spiral pyrolysis device with a concave pressure roller of the present invention comprises:

[0009] The furnace body is a hollow circular tube arranged obliquely, the head end of the furnace body is higher than the tail end, a feed inlet is provided at the top of the head end of the furnace body, a discharge port is provided at the bottom of the tail end of the furnace body, and a gas outlet is provided at the top of the tail end of the furnace body; a continuous crushing section and a reaction section are formed in the furnace body from the head end to the tail end;

[0010] A rotating shaft, the rotating shaft is coaxially disposed in the furnace body and can rotate in the furnace body, and the rotating shaft extends from the head end to the tail end of the furnace body;

[0011] A concave pressure roller, wherein the concave pressure roller is a solid cylindrical roller body, the roller body is coaxially fixed on the rotating shaft in the crushing section, and a plurality of grooves are arranged on the circumferential side surface of the roller body, which are spaced and parallel to the rotating shaft; the grooves gradually become shallower from the beginning to the end of the crushing section; on the cross section of the concave pressure roller, the groove depth of one side wall of a single groove gradually increases along the rotation direction of the rotating shaft;

[0012] A stirring blade is fixed on the rotating shaft in the reaction section.

[0013] Optionally, a friction layer is provided on the surface of the groove and the inner wall of the crushing 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 reaction section, and the pyrolysis gas channel is directly connected to the gas outlet.

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

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

[0017] Optionally, the diameter of the roller body is the same as the diameter of the stirring blade; the structure of each of the grooves is the same and is symmetrically distributed around the axis of the rotating shaft; the maximum groove depth of the groove on the end surface of the head end of the roller body is 0.2 to 0.4 times the diameter of the roller body, and the maximum groove depth on the end surface of the tail end of the roller body is 0.05 to 0.1 times the diameter of the roller body; the minimum groove depth of the groove is 0 to 3 mm.

[0018] Optionally, on the end surface of the front end of the concave pressing roller, the sum of the central angles of all the grooves is 180-300°; and the spacing between the grooves of adjacent grooves is greater than 10 mm.

[0019] Optionally, a heat-insulating layer is arranged inside the furnace wall of the furnace body.

[0020] Furthermore, the present invention also provides a pyrolysis method, which is implemented based on the above-mentioned spiral pyrolysis device with a concave pressure roller, and comprises the following steps:

[0021] S1, driving the rotating shaft to rotate, driving the concave pressure roller and the stirring blade to rotate at a set speed, and at the same time heating the crushing section and the reaction section of the furnace body to a set temperature respectively;

[0022] 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 groove and the inner wall of the crushing section, the raw materials are crushed and contacted with the catalyst in the crushing section;

[0023] S3. Under the action of gravity and friction, the mixture of raw materials and catalyst enters the reaction section, the raw materials are heated and catalytic pyrolysis occurs;

[0024] S4, the pyrolysis gas generated in the reaction section is discharged through the gas outlet, and then condensed and separated to obtain pyrolysis oil and non-condensable gas;

[0025] 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 stirring blades and gravity.

[0026] Optionally, the set temperature of the crushing section is 100-200°C; the set temperature of the reaction section is 400-600°C;

[0027] And / or, the rotation speed of the rotating shaft is 5 to 15 r / min.

[0028] (III) Beneficial effects

[0029] The pyrolysis device and method provided by the technical solution of the present invention realizes 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 section of the furnace body and the friction layer on the outer surface of the concave pressure roller, and effectively enhances the heat transfer and mass transfer effect. The raw material enters the furnace crushing section of the pyrolysis device, and continues to move forward in the gap space between the groove of the concave pressure roller and the inner wall of the crushing section, which is constantly shrinking. Through the mutual squeezing 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 reaction section of the furnace body. The raw material is rapidly heated and catalytic pyrolysis occurs. Under the stirring and pushing action of the stirring 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 stirring blades and gravity and subjected to subsequent treatment.

[0030] The beneficial effects of the above technical solution of the present invention are as follows:

[0031] 1. High space utilization: No additional auxiliary pretreatment equipment is required, and the crushing section for raw material pretreatment and the pyrolysis reaction section are arranged in the same furnace body. The device has a compact structure and improves space utilization.

[0032] 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 the concave pressure rollers with different groove structures, precise crushing of specific fruit shell biomass can be achieved. It is also suitable for other organic solid waste raw materials with lower hardness.

[0033] 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.

[0034] 4. Segmented precise temperature control: Through segmented precise temperature control in the crushing section and the reaction section, 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.

[0035] 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.

[0036] 6. Stable operation of the device: The crushing section pre-processes the hard fruit shell waste, making the stirring blades in the reaction section less likely to be worn or stuck, thus ensuring the smooth and continuous operation of the rotating mechanism.

[0037] 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.

[0038] 8. Automatic exhaust and pressure protection: In the reaction section, the efficient pyrolysis of the raw materials causes the rapidly expanding pyrolysis gas to be collected through the pyrolysis gas channel above the furnace body and discharged from the gas outlet, avoiding excessive pressure in the reaction section affecting the pyrolysis reaction.

[0039] 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 stirring blades to prevent the pipes in the furnace from being blocked.

[0040] 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

[0041] Figure 1 It is a schematic structural diagram of a spiral pyrolysis device with a concave pressure roller of the present invention;

[0042] Figure 2 It is a cross-sectional schematic diagram of a concave pressing roller with a planar groove according to the present invention;

[0043] Figure 3 It is a schematic cross-sectional view of a concave pressing roller with curved grooves according to the present invention.

[0044] [Description of Reference Numerals]

[0045] 1: furnace body; Z1: crushing section; Z2: reaction section; 11: feed inlet; 12: discharge outlet; 13: gas outlet; 14: insulation layer; 15: pyrolysis gas channel;

[0046] 2: rotating shaft; 3: concave pressure roller; 31: roller body; 32: groove; 4: stirring blade; 5: friction layer. DETAILED DESCRIPTION

[0047] 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.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] See also Figure 1 The present invention provides a spiral pyrolysis device with a concave pressure roller, which includes: a furnace body 1, a rotating shaft 2, a concave pressure roller 3 and a stirring blade 4. The furnace body 1 is a hollow circular tube arranged obliquely, the head end of the furnace body 1 is higher than the tail end, a feed port 11 is provided at the top of the head end of the furnace body 1 for feeding raw materials such as fruit shell waste, a discharge port 12 is provided at the bottom of the tail end of the furnace body 1 for the discharge of pyrolytic carbon, and a gas outlet 13 is provided at the top of the tail end of the furnace body 1 for the discharge of pyrolytic gas. Among them, the axial direction of the furnace body 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 head end to the lower tail end, but the flow speed will not be too fast to affect the pyrolysis reaction. Moreover, a continuous crushing section Z1 and a reaction section Z2 are formed in the furnace body 1 from the head end to the tail end, that is, a section near the head end of the pyrolysis furnace 1 is the crushing section Z1, and a section near the tail end is the reaction section Z2, and the tail end of the crushing section Z1 and the head end of the reaction section Z2 are connected to each other, wherein the crushing section Z1 and the reaction section Z2 are respectively provided with independent heating mechanisms, such as electric heating tubes, so that segmented independent temperature control can be achieved. Through segmented and precise temperature control of the crushing section Z1 and the reaction 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 furnace body 1 to prevent heat loss. Moreover, the crushing section Z1 and the reaction section Z2 are continuously arranged in the furnace body 1, eliminating the need for additional auxiliary pretreatment equipment. The crushing section Z1 for pretreatment of raw materials and the reaction section Z2 for pyrolysis are arranged in the same furnace body 1, making the device structure compact and improving space utilization.

[0052] The rotating shaft 2 is coaxially arranged in the furnace body 1 and can rotate in the furnace body 1. The rotating shaft 2 extends from the head end to the tail end of the furnace body 1. The rotating shaft 2 is rotatably supported by bearings on the end covers at both ends of the furnace body 1, and is sealed at both ends of the axial direction of the furnace body 1. Moreover, the rotating shaft 2 is driven by an external rotating 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.

[0053] The concave pressure roller 3 is a solid cylindrical roller body 31 ( Figure 1The position of the middle roller body 31 is filled with a section line), the roller body 31 is coaxially fixed on the rotating shaft 2 in the crushing section Z1, the roller body 31 and the rotating shaft 2 can be integrally formed, or they can be axially and circumferentially limited and fixed by fasteners and keys, and a plurality of grooves 32 are arranged on the circumferential side surface of the roller body 31, which are spaced and parallel to the rotating shaft 2. Among them, the groove 32 gradually becomes shallower from the beginning to the end of the crushing section Z1, that is, the average groove depth of the groove 32 (that is, the average value of the radial distance from any point on the working surface of any cross section of the concave pressure roller 3 to the groove opening) gradually decreases from the beginning to the end of the crushing section Z1. Moreover, as Figure 2 and Figure 3 As shown, on the cross section of the concave pressure roller 3, the grooves 32 can all be V-shaped grooves (the tip of the "V" is the groove bottom, and the opening of the "V" is the notch. Specifically, the notch of the groove 32 is located on the circumferential side of the roller body 31 and opposite to the groove bottom). The groove depth of one side wall of the single groove 32 (which corresponds to the working surface) gradually increases along the rotation direction of the rotating shaft 2. During rotation, the raw material can be pressed onto the working surface, and the space between the working surface and the furnace body 1 gradually becomes smaller, which can provide sufficient pressure for friction crushing; and the other side wall opposite to the working surface basically extends along the radial direction of the rotating shaft 2. Among them, it can be seen from the cross section of the groove 32 that the working surface can be preferably an inclined plane (the groove 32 at this time corresponds to a plane groove, see Figure 2 ) or curved surface (the groove 32 in this case corresponds to a curved groove, see Figure 3 ), as long as the raw materials can be efficiently crushed.

[0054] By setting the concave roller 3 in this way, after the raw material enters the crushing section Z1 in the furnace body 1, it can continue to move forward in the gap space that is constantly shrinking between the groove 32 of the concave roller 3 and the inner wall of the crushing section Z1, thereby realizing 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 concave roller 3 with different groove structures, 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 concave roller 3 and the inner wall of the crushing section Z1 to crush the fruit shell waste, it can effectively improve the degree of full contact with the catalyst and enhance the heat and mass transfer effects.

[0055] Also, see again Figure 1 The stirring blade 4 is fixed on the rotating shaft 2 in the reaction section Z2. The solid carbon and waste residue left by pyrolysis will be automatically discharged through the discharge port 12 under the force of gravity and the pushing action of the stirring blade 4, preventing the pipeline in the furnace body 1 from being blocked. The crushing section Z1 pre-processes the hard fruit shell waste by crushing, so that the stirring blade 4 in the reaction section is not easy to be worn or stuck, which can ensure the smooth and continuous operation of the rotating mechanism.

[0056] Furthermore, in a preferred embodiment, a friction layer 5 may be provided on the surface of the groove 32 and the inner wall of the 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.

[0057] In addition, a groove-shaped pyrolysis gas channel 15 is provided on the inner wall at the top of the reaction section Z2, and the pyrolysis gas channel 15 is directly connected to the gas outlet 13, so that the pyrolysis gas can be collected and flowed inside the furnace body 1, and can also play a guiding role so that the pyrolysis gas can be discharged from the furnace body 1 more quickly. In the reaction 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 furnace body 1 and discharged from the gas outlet 13, so as to avoid excessive pressure in the reaction section Z2 and affect the pyrolysis reaction.

[0058] Through the interaction between the inner surface of the crushing section Z1 of the furnace body 1 and the friction layer 5 on the outer surface of the concave roller 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 materials enter the crushing section Z1 of the furnace body 1 of the pyrolysis device, and continue to move forward in the gap space between the groove 32 of the concave roller 3 and the inner wall of the crushing section Z1, which is constantly reduced. Through the mutual extrusion and friction of the friction layer 5 on the surface, efficient crushing pretreatment of fruit shell waste is achieved. After the crushed raw materials and the catalyst are fully mixed, they enter the reaction section Z2 of the furnace body 1. The raw materials are rapidly heated and catalytically pyrolyzed. Under the stirring and pushing action of the stirring blades 4, the raw materials continue to move forward and are 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 residues remaining from the pyrolysis are discharged under the action of the stirring blades 4 and gravity and are subsequently treated. Pyrolysis is carried out in a closed furnace body 1, which is an oxygen-free process and can produce reducing components such as H2 and CO. 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. It 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.

[0059] In a more preferred embodiment, see again Figure 1The stirring blade 4 is a spiral blade coaxially arranged with the rotating shaft 2. The diameter of the stirring blade 4 remains unchanged in the reaction section Z2, and the gap between the outer edge of the stirring blade 4 and the inner wall of the furnace body 1 (i.e., the circumferential inner surface of the furnace body 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 stirring blade 4 can be designed to be 30 to 100 mm according to actual needs. Furthermore, in actual production, the diameter of the roller body 31 can be designed to be the same as the diameter of the stirring blade 4; the structure of each groove 32 is the same and is symmetrically distributed around the axis center of the rotating shaft 2; the maximum groove depth of the groove 32 on the end face of the head end of the roller body 31 (that is, the groove depth of the groove 32 at the bottom of the groove at the head end) is 0.2 to 0.4 times the diameter of the roller body 31, and the maximum groove depth on the end face of the end of the roller body 31 (that is, the groove depth of the groove 32 at the bottom of the groove at the end) is 0.05 to 0.1 times the diameter of the roller body 31; the minimum groove depth is 0 to 3 mm, and the working surface groove depth varies from the maximum groove depth to the minimum groove depth, and the minimum groove depth should be close to 0. If the minimum groove depth is too large, it may cause the raw materials to aggregate and fail to provide sufficient pressure. Moreover, on the end face of the front end of the concave pressing roller 3, the sum of the central angles corresponding to the notches of all the grooves 32 is 180 to 300°. In addition, the spacing between the notches of adjacent grooves 32 is greater than 10 mm. Such a clever arrangement enables the concave pressing roller 3 to achieve optimal efficiency when crushing the raw materials.

[0060] Furthermore, the present invention also provides a pyrolysis method, which is implemented based on the above-mentioned spiral pyrolysis device with a concave pressure roller, and comprises the following steps:

[0061] S1, start the rotary driver to drive the rotary shaft 2 to rotate, drive the concave pressure roller 3 and the stirring blade 4 to rotate at a set speed, and heat the crushing section Z1 and the reaction section Z2 of the furnace body 1 to the set temperature respectively;

[0062] 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 groove 32 and the inner wall of the crushing section Z1, the raw materials are crushed in the crushing section Z1, and the size of the raw materials gradually becomes smaller and fully contacts the catalyst;

[0063] S3, under the action of gravity and friction, the mixture of raw materials and catalyst enters the reaction section Z2, the raw materials are rapidly heated and catalytic pyrolysis occurs;

[0064] S4, the pyrolysis gas generated in the reaction section Z2 is gathered in the pyrolysis gas channel 15 and discharged through the gas outlet 13, and then condensed and separated to obtain pyrolysis oil and non-condensable gas;

[0065] 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 stirring blades 4 and gravity.

[0066] The raw material enters the crushing section Z1 of the furnace body 1 of the pyrolysis device, and continues to move forward in the gap space between the groove 32 of the concave pressure roller 3 and the inner wall of the crushing section Z1, which is constantly shrinking. 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.

[0067] Among them, in order to improve the catalytic pyrolysis efficiency of the raw materials, the set temperature of the crushing section Z1 is 100-200°C; the set temperature of the reaction section Z2 is 400-600°C. Through the segmented and precise temperature control of the crushing section Z1 and the reaction 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 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 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.

[0068] The following is a detailed description of the process flow of pyrolysis using a spiral pyrolysis device with a concave pressure roller through specific embodiments, and each embodiment uses a device with basically the same structure.

[0069] Example 1

[0070] The inner diameter of the furnace body 1 is 300 mm, the length of the crushing section Z1 of the furnace body 1 is 500 mm, and the length of the reaction section Z2 is 1000 mm; the diameter of the rotating shaft 2 is 100 mm; the diameter of the roller body 31 of the concave pressing roller 3 is 260 mm; the concave pressing roller 3 is provided with 8 grooves 32 which are evenly distributed and rotationally symmetrical around the rotating shaft 2, and the grooves 32 are plane grooves (see Figure 2 ), the average groove depth of each groove 32 gradually decreases from 20mm at the head end to 5mm at the end end, and the minimum groove depth on each axial section is 1mm; on the end face of the head end of the concave pressure roller 3, the sum of the central angles corresponding to the notches of the 8 grooves 32 is 300°, and the spacing between the notches of adjacent grooves 32 is about 17mm; the outer diameter of the stirring blade 4 is 296mm, the spacing between the edge of the stirring blade 4 and the inner wall of the furnace body 1 is 2mm, and the pitch of the stirring blade 4 is 50mm.

[0071] Walnut shell raw materials with an average particle size of 20 mm are mixed with activated carbon catalyst and sent to the furnace body 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 reaction section Z2 with a temperature set to 450°C. Under the stirring and pushing of the stirring 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 39.8wt%. Phenolic substances in the bio-oil account for 65.5% of the detectable organic components, of which phenol accounts for 38.8%, realizing the high-value utilization of walnut shell waste.

[0072] Example 2

[0073] The difference between this embodiment and the embodiment 1 is that the structure of the concave pressing roller 3 is changed. The diameter of the roller body 31 of the concave pressing roller 3 is 250 mm. The concave pressing roller 3 is provided with 9 grooves 32 which are evenly distributed and rotationally symmetrical around the rotating axis 2. The grooves 32 are curved grooves (see Figure 3 ), the average groove depth of each groove 32 gradually decreases from 15mm at the head end to 3mm at the end end, and the minimum groove depth on each axial section is 1mm; on the end face of the head end of the concave pressure roller 3, the sum of the central angles corresponding to the notches of the 9 grooves 32 is 300°, and the spacing between the notches of adjacent grooves 32 is about 14.5mm.

[0074] The coconut shell raw material with an average particle size of 30 mm was mixed with K2CO3 catalyst and fed into the furnace body 1. The temperature of the crushing 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 fed into the reaction section Z2 with a temperature set to 600°C. Under the stirring and pushing of the stirring blade 4, the temperature was rapidly increased and a pyrolysis reaction occurred. The solid product remaining from the pyrolysis was collected, and the solid phase yield was 41.2wt%. The final specific surface area was 2038.1cm 2 / g, pore size distribution of 2 to 50nm, and mesoporous activated carbon have achieved high-value utilization of coconut shell waste.

[0075] Example 3

[0076] The difference between this embodiment and embodiment 1 is that the pitch of the stirring blade 4 is 30 mm.

[0077] The oil tea shell raw material with an average particle size of 20 mm is mixed with a zinc chloride catalyst and sent to the furnace body 1. The temperature of the crushing section Z1 is set to 100°C, and the speed of the rotating shaft 2 is 5r / min. The raw material is crushed, and the average particle size is reduced to 5mm. Then the raw material is sent to the reaction section Z2 with a temperature set to 400°C. Under the stirring and pushing of the stirring blade 4, the temperature gradually rises and a pyrolysis reaction occurs. The pyrolysis gas is collected and quickly separated and condensed. The yield of the liquid product is 44.6wt%, and the target product furfural accounts for 41.4% of the liquid product, realizing the high-value utilization of oil tea shell waste.

[0078] Example 4

[0079] The difference between this embodiment and embodiment 1 is that the pitch of the stirring blade 4 is 100 mm.

[0080] The chestnut shells with an average particle size of 20 mm were fed into the furnace body 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 reaction section Z2 with a temperature set to 500°C. Under the stirring and pushing of the stirring blades 4, the temperature gradually increased and a pyrolysis reaction occurred. The combustible pyrolysis gas was collected, and the gas yield reached 65.64wt% and the average calorific value reached 13.0MJ / m 3 , realizing the high-value utilization of chestnut shell waste.

[0081] 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 concave pressure roller, characterized in that: include: A furnace body (1), wherein the furnace body (1) is a hollow circular tube arranged obliquely, the head end of the furnace body (1) is higher than the tail end, a feed port (11) is provided at the top of the head end of the furnace body (1), a discharge port (12) is provided at the bottom of the tail end of the furnace body (1), and a gas outlet (13) is provided at the top of the tail end of the furnace body (1); a continuous crushing section (Z1) and a reaction section (Z2) are formed in the furnace body (1) from the head end to the tail end; the crushing section (Z1) and the reaction section (Z2) are respectively provided with independent heating mechanisms; A rotating shaft (2), the rotating shaft (2) being coaxially arranged in the furnace body (1) and being capable of rotating in the furnace body (1), the rotating shaft (2) extending from the head end to the tail end of the furnace body (1); A concave pressure roller (3), wherein the concave pressure roller (3) is a solid cylindrical roller body (31), the roller body (31) is coaxially fixed on the rotating shaft (2) in the crushing section (Z1), and a plurality of grooves (32) are arranged on the circumferential side surface of the roller body (31), which are spaced apart and parallel to the rotating shaft (2); the grooves (32) gradually become shallower from the beginning to the end of the crushing section (Z1); and in the cross section of the concave pressure roller (3), the groove depth of one side wall of a single groove (32) gradually increases along the rotation direction of the rotating shaft (2); A stirring blade (4), wherein the stirring blade (4) is fixed on the rotating shaft (2) in the reaction section (Z2).

2. The spiral pyrolysis device with concave pressure roller according to claim 1, characterized in that: A friction layer (5) is provided on the surface of the groove (32) and the inner wall of the crushing section (Z1); the friction layer (5) is a texture and / or a wear-resistant coating.

3. The spiral pyrolysis device with concave pressure roller 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 reaction section (Z2), and the pyrolysis gas channel (15) is directly connected to the gas outlet (13).

4. The spiral pyrolysis device with concave pressure roller according to any one of claims 1 to 3, characterized in that: The axial direction of the furnace body (1) forms an angle of 15 to 45 degrees with the horizontal direction.

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

6. The spiral pyrolysis device with concave pressure roller according to any one of claims 1 to 3, characterized in that: The diameter of the roller body (31) is the same as the diameter of the stirring blade (4); each of the grooves (32) has the same structure and is symmetrically distributed around the axis of the rotating shaft (2); the maximum groove depth of the groove (32) on the end surface of the head end of the roller body (31) is 0.2 to 0.4 times the diameter of the roller body (31), and the maximum groove depth on the end surface of the tail end of the roller body (31) is 0.05 to 0.1 times the diameter of the roller body (31); and the minimum groove depth of the groove (32) is 0 to 3 mm.

7. The spiral pyrolysis device with concave pressure roller according to any one of claims 1 to 3, characterized in that: On the end surface of the front end of the concave pressing roller (3), the sum of the central angles corresponding to the notches of all the grooves (32) is 180-300°; and the spacing between the notches of adjacent grooves (32) is greater than 10 mm.

8. The spiral pyrolysis device with concave pressure roller according to any one of claims 1 to 3, characterized in that: A heat-insulating layer (14) is arranged inside the furnace wall of the furnace body (1).

9. A pyrolysis method, which is implemented based on the spiral pyrolysis device with concave pressure rollers according to any one of claims 1 to 8, characterized in that: The pyrolysis method comprises the following steps: S1, driving the rotating shaft (2) to rotate, driving the concave pressure roller (3) and the stirring blade (4) to rotate at a set speed, and at the same time heating the crushing section (Z1) and the reaction section (Z2) of the furnace body (1) to a set temperature respectively; S2, adding 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 groove (32) and the inner wall of the crushing section (Z1), the raw materials are crushed and brought into contact with the catalyst in the crushing section (Z1); S3. Under the action of gravity and friction, the mixture of raw materials and catalyst enters the reaction section (Z2), the raw materials are heated and catalytic pyrolysis occurs; S4, the pyrolysis gas generated in the reaction section (Z2) is discharged through the gas outlet (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 stirring blade (4) and gravity.

10. The pyrolysis method according to claim 9, characterized in that The setting temperature of the crushing section (Z1) is 100-200°C; the setting temperature of the reaction section (Z2) is 400-600°C; And / or, the rotation speed of the rotating shaft (2) is 5-15 r / min.

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