Conveyor-type cracking furnace

Abstract

The application relates to the technical field of conveyor belt type cracking furnaces, and provides a conveyor belt type cracking furnace for cracking fiber composite materials, which comprises a furnace body and a conveyor belt arranged through the furnace body; a cracking gas extraction device arranged on the furnace body and used for extracting cracking gas generated by pyrolysis of the fiber composite materials in the furnace body; and an air curtain device arranged at the inlet and outlet of the conveyor belt and used for releasing superheated steam to generate an air curtain and heat the fiber composite materials. The conveyor belt type pyrolysis furnace in the application utilizes the conveyor belt to convey the fiber composite materials, and utilizes the superheated steam to heat the fiber composite materials during the conveying process, so that the fiber composite materials are subjected to pyrolysis reaction. In this way, the fiber composite materials can be continuously fed and discharged, the process of repeated temperature rising and falling is omitted, the time period is short, the heat utilization rate is high, and the fiber composite materials can be continuously recovered.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of material recycling equipment, in particular to a conveyor belt type pyrolysis furnace. BACKGROUND

[0002] Fiber-reinforced composites have the advantages of light weight, high strength, high modulus, corrosion resistance, etc., and are widely used in aerospace, sports and leisure, automobiles, buildings and bridge reinforcement, etc. In 2018, the total output of composites in China was 4.3 million tons, and it is predicted that it will reach about 5.56 million tons in 2023, ranking second in the world after Germany and Japan. However, as the application of composites in China becomes more and more extensive, how to properly dispose of composite waste has become a problem that must be solved. The existing fiber-reinforced composites are mainly thermosetting resins, which cannot be degraded under natural conditions. Discarded glass steel fan blades, carbon fiber composites and the like have caused serious environmental pollution and a large amount of resource waste. At present, the recycling of fiber-reinforced composite waste has not yet entered the industrialization in China. Even globally, only a few companies in Japan, Germany, the United Kingdom and other countries have carbon fiber-reinforced composite recycling industries.

[0003] Nowadays, the industry usually recycles fiber composites by pyrolysis. However, the existing pyrolysis furnace is usually non-continuous, i.e. loading, pyrolysis, and taking out after pyrolysis is completed. This way of heating pyrolysis and cooling unloading cannot make good use of heat, and has long cycle, high cost and low efficiency. Therefore, there is an urgent need for a pyrolysis furnace that can perform continuous pyrolysis. SUMMARY

[0004] In order to solve or at least partially solve the above technical problems, the present application provides a conveyor belt type pyrolysis furnace.

[0005] A conveyor belt type pyrolysis furnace for pyrolyzing fiber composites, comprising:

[0006] a furnace body and a conveyor belt passing through the furnace body;

[0007] a pyrolysis gas extraction device arranged on the furnace body for extracting pyrolysis gas generated by pyrolysis of the fiber composites in the furnace body;

[0008] an air curtain device arranged at the inlet and outlet of the conveyor belt, the air curtain device being used to release superheated steam to generate an air curtain and heat the fiber composites.

[0009] Further technical solutions can also be that the conveyor belt comprises:

[0010] a feeding side, a discharging side and a central conveying part;

[0011] The height of the part of the central conveying part supporting the material is greater than the part of the feeding side.

[0012] Further technical solutions can also include:

[0013] A feeding pipe and a discharging pipe are connected to the furnace body respectively.

[0014] The conveying belt enters the furnace body through the feeding pipe and extends out of the furnace body through the discharging pipe.

[0015] The feeding pipe has a first included angle with the horizontal plane, and the first included angle is in the range of 10° to 35°.

[0016] Further technical solutions can also include that the gas curtain device includes:

[0017] An air inlet gas curtain mechanism is arranged in the feeding pipe.

[0018] The air inlet gas curtain mechanism includes a plurality of gas curtain nozzles, which release superheated steam in the direction of the conveying belt to generate a gas curtain and heat the fiber composite material.

[0019] Further technical solutions can also include that the gas curtain nozzles are arranged in at least two rows along the movement direction of the conveying belt, and the jet directions of the gas curtain nozzles in adjacent two rows are staggered with each other.

[0020] Further technical solutions can also include a pyrolysis pipe arranged in the furnace body.

[0021] The two ends of the pyrolysis pipe are connected to the feeding pipe and the discharging pipe respectively.

[0022] The conveying belt passes through the pyrolysis pipe, and the fiber composite material is pyrolyzed in the pyrolysis pipe.

[0023] The pyrolysis pipe and the furnace body have a heating cavity, and the pyrolysis gas extraction device is connected to the pyrolysis pipe through the heating cavity.

[0024] An auxiliary heating device is arranged in the heating cavity.

[0025] Further technical solutions can also include that the auxiliary heating device includes:

[0026] A heat source inlet passes through the outer wall of the furnace body and is connected to the heating cavity, for introducing high-temperature gas into the heating cavity to heat the pyrolysis pipe.

[0027] A heat source outlet passes through the outer wall of the furnace body and is connected to the heating cavity, for discharging the high-temperature gas.

[0028] Further technical solutions can also be that the auxiliary heating device further comprises:

[0029] An electric heating assembly is arranged on the inner wall of the furnace body and can heat at least part of the cracking pipeline;

[0030] A temperature sensor is arranged for measuring the temperature in the cracking pipeline, and the temperature sensor is in communication connection with the electric heating assembly.

[0031] Further technical solutions can also be that the cracking gas exhaust device comprises:

[0032] A cracking gas outlet is arranged on the furnace body and is in communication with the cracking pipeline, and is used for releasing cracking gas;

[0033] A pressure controller is connected with the cracking gas outlet and adjusts the gas pressure in the cracking pipeline by controlling the gas flow of the cracking gas outlet.

[0034] Further technical solutions can also be that the pressure controller comprises:

[0035] A pressure sensor is arranged in the cracking pipeline and detects the pressure in the cracking pipeline;

[0036] A fan is in communication connection with the pressure sensor, and the fan is arranged opposite to the cracking gas outlet;

[0037] A pressure relief pipeline is connected with the cracking gas outlet, the fan is installed in the pressure relief pipeline, and the blowing direction of the fan is toward the direction of the cracking gas outlet;

[0038] A one-way valve is arranged in the pressure relief pipeline.

[0039] The conveyor belt type pyrolysis furnace in the present application uses a conveyor belt to convey fiber composite materials, and uses superheated steam to heat the fiber composite materials during the conveying process, so that the fiber composite materials are subjected to pyrolysis reaction. This way can continuously feed and discharge, saves the process of repeated heating and cooling, has a short time period, high heat utilization rate, and can continuously recover fiber composite materials. BRIEF DESCRIPTION OF DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the present application, the related drawings will be briefly introduced below. It can be understood that the drawings described below are only used to illustrate some embodiments of the present application, and those skilled in the art can also obtain many other technical features and connection relationships not mentioned in the text from these drawings.

[0041] Figure 1 A structure schematic diagram of a conveyor belt type pyrolysis furnace provided by the present application is shown in the figure;

[0042] Figure 2 A structure diagram of a pyrolysis gas extraction device of a conveyor belt type pyrolysis furnace is provided for the present application.

[0043] Figure 3 A structure diagram of a gas curtain device of a conveyor belt type pyrolysis furnace is provided for the present application.

[0044] The reference signs and names in the drawings are as follows:

[0045] 1, furnace body; 11, feeding pipe; 12, discharging pipe; 13, pyrolysis pipe; 2, conveyor belt; 21, feeding side; 22, discharging side; 23, central conveying part; 3, pyrolysis gas extraction device; 4, gas curtain device; 41, gas inlet gas curtain mechanism; 42, gas curtain nozzle; 5, heating cavity; 51, heat source inlet; 52, heat source outlet; 6, electric heating assembly; 7, pyrolysis gas outlet; 8, fan; 9, pressure relief pipe; 10, one-way valve; 15, water cooling device; 16, anti-leakage pipe; 17, valve. DETAILED DESCRIPTION

[0046] The technical solutions in the embodiments of the present application will be described in detail below with reference to the drawings in the embodiments of the present application.

[0047] The inventors of the present application found that in the prior art, the industry usually recycles fiber composite materials by pyrolysis. However, the existing pyrolysis furnace is usually non-continuous, that is, loading, pyrolysis, and opening the furnace to take out after pyrolysis is completed. This way of heating pyrolysis and cooling unloading cannot make good use of heat, and has long cycle, high cost, and low efficiency.

[0048] Therefore, the present application provides a conveyor belt type pyrolysis furnace to facilitate large-scale, continuous, low-cost, and low-energy recycling of fiber composite materials.

[0049] Embodiment one

[0050] The first embodiment of the present application proposes a conveyor belt type pyrolysis furnace, as shown in the figure, which is used for pyrolyzing fiber composite materials and includes: Figure 1

[0051] a furnace body 1 and a conveyor belt 2 passing through the furnace body 1;

[0052] a pyrolysis gas extraction device 3 arranged on the furnace body 1 and used for extracting pyrolysis gas generated by pyrolysis of the fiber composite materials in the furnace body 1;

[0053] a gas curtain device 4 arranged at the inlet and outlet of the conveyor belt 2, the gas curtain device 4 being used for releasing superheated steam to generate a gas curtain and heat the fiber composite materials.

[0054] ​The furnace body 1 in the present application serves as the frame structure of the conveyor belt type pyrolysis furnace. On the one hand, it provides mounting positions for various parts; on the other hand, it also serves as the reaction cavity of the pyrolysis reaction, and is used to isolate the pyrolysis reaction from the outside world, to provide an independent reaction site for the pyrolysis reaction, so as to ensure the smooth progress of the reaction. In the embodiment of the present application, the furnace body 1 can be arranged in a horizontal structure, and various support members such as support beams and support columns are arranged at the bottom for supporting the furnace body 1. In addition, the furnace body 1 in the present application can be wrapped with thermal insulation materials on the outside, so as to avoid the loss of internal heat and reduce energy consumption, and also to isolate the internal heat, so as to avoid the scalding of workers caused by accidental touching.

[0055] The conveyor belt 2 is driven to operate by a driving mechanism. The fiber composite materials to be processed are placed on the conveyor belt 2, and are driven by the conveyor belt 2 to enter the furnace body 1 from the inlet of the furnace body 1, and are discharged from the outlet of the furnace body 1. When the fiber composite materials are located inside the furnace body 1, the pyrolysis reaction is carried out; and when the reaction is terminated, the fiber composite materials are discharged from the outlet of the furnace body 1. In actual practical process, the time required for the pyrolysis reaction to be completed is different for different fiber composite materials. The person skilled in the art can adjust the moving speed of the conveyor belt 2 according to the type of the fiber composite materials, so as to adjust the reaction time of the fiber composite materials, so as to ensure that the reaction is complete.

[0056] When the fiber composite materials are conveyed by the conveyor belt 2, they need to enter from one side of the furnace body 1 and leave from the other side. Therefore, a certain gap needs to be left at the positions corresponding to the conveyor belt 2 on both sides of the furnace body 1, so as to allow the conveyor belt 2 and the fiber composite materials placed thereon to pass through. Due to the existence of the above-mentioned gap, the furnace body 1 cannot be completely sealed. The air outside the furnace body 1 can enter the inside of the furnace body 1 from these gaps, which affects the progress of the pyrolysis reaction inside the furnace body 1.

[0057] In order to solve the above-mentioned problem, an air curtain device 4 is arranged at the inlet and outlet of the conveyor belt 2. The air curtain device 4 is used to release superheated steam to generate an air curtain.

[0058] The air curtain, which essentially belongs to an air curtain, is a gas flow barrier with a certain thickness formed by the sprayed high-speed gas. The gas flow barrier formed by the high-speed gas flow can isolate the space inside and outside the furnace body 1 from each other to a certain extent, not only can prevent the internal gas of the furnace body 1 from leaking to the outside, but also can prevent the external gas from entering the inside of the furnace body 1, so as to avoid the influence of the oxidizing gas on the pyrolysis reaction. In addition, by arranging the gas flow barrier, the flow of the gas inside and outside the furnace body 1 can be isolated, the heat exchange between the gas inside and outside the furnace body 1 is effectively reduced, and the loss of the internal heat of the furnace body 1 is effectively avoided.

[0059] The cracking gas extraction device 3 is used to extract the cracking gas generated by the pyrolysis of the fiber composite material in the furnace body 1. It should be noted that the cracking gas extraction device 3 is used to extract the cracking gas in the furnace body 1 on the one hand, and on the other hand, the gas flow of the cracking gas extraction device 3 can be controlled to adjust the gas pressure in the furnace body 1, so that the gas pressure in the furnace body 1 is less than the atmospheric pressure (i.e. the furnace body 1 is in a negative pressure state). In this way, the gas pressure in the furnace body 1 is less than the atmospheric pressure, and the gas in the furnace body 1 is difficult to leak to the outside, thereby avoiding waste.

[0060] In particular, in the present embodiment, the air curtain device 4 generates an air curtain by releasing superheated steam, and also uses the superheated steam to heat the fiber composite material entering the furnace body 1.

[0061] Specifically, the air curtain device 4 is arranged at the inlet and outlet of the conveying belt 2. In the present embodiment, the air curtain device 4 includes two, which are respectively arranged at the inlet and outlet of the furnace body 1, and correspond to the inlet and outlet of the conveying belt 2. When the fiber composite material passes through the air curtain device 4, it will be heated by the superheated steam released by the air curtain device 4. In addition, due to the fact that the gas pressure in the furnace body 1 is less than the atmospheric pressure, the superheated steam released by the air curtain device 4 at the inlet and outlet of the furnace body 1 will be sucked into the furnace body 1 under the action of the gas pressure. Specifically, the superheated steam released by the air curtain device 4 at the inlet of the furnace body 1 enters the furnace body 1 in the moving direction of the fiber composite material under the action of the gas pressure; the superheated steam released by the air curtain device 4 at the outlet of the furnace body 1 enters the furnace body 1 against the moving direction of the fiber composite material under the action of the gas pressure.

[0062] The superheated steam can heat the furnace body 1 and the fiber composite material in the furnace body 1 at the same time when entering the furnace body 1. The cracking gas extraction device 3 extracts the excess superheated steam entering the furnace body 1 and the cracking gas generated by the pyrolysis reaction in the furnace body 1 from the furnace body 1, so as to maintain the negative pressure in the furnace. The extracted gas can be recycled. For example, the cracking gas can be separated and the superheated steam can be recycled.

[0063] In the present embodiment, the gas flow of the cracking gas extraction device 3 can be controlled, so that the superheated steam released by the air curtain device 4 can be sucked into the furnace body 1, preventing the superheated steam from leaking to the outside, and reducing the loss of superheated steam. In addition, the superheated steam can be released by the air curtain device 4 to form an air curtain to prevent external air from entering the furnace body 1, thereby avoiding affecting the pyrolysis reaction in the furnace body 1; or the superheated steam can be used as a heating source to heat the furnace body 1 and the fiber composite material. In this way, the superheated steam can be effectively utilized, the utilization rate of the superheated steam can be improved, and the cost can be reduced.

[0064] In addition, the pyrolysis reaction is usually carried out in an oxygen-free environment. Therefore, the superheated steam can be oxygen-free or micro-oxygen, normal pressure and high temperature superheated steam. The superheated steam can be used as a heating source for the fiber composite material and an oxygen-free or micro-oxygen protection medium for the pyrolysis reaction of the fiber composite material, so as to protect and heat the fiber composite material. Specifically, the superheated steam can be obtained by heating water to generate saturated steam and further heating the saturated steam. When the carbon fiber composite material is pyrolyzed and recovered, the superheated steam can be superheated steam with an oxygen content of less than 0.3%, normal pressure and a temperature of 400-700°C.

[0065] The conveyor belt 2 type pyrolysis furnace in the present application uses the conveyor belt 2 to transport the fiber composite material and uses the superheated steam to heat the fiber composite material during the transportation, so as to make the fiber composite material perform the pyrolysis reaction. In this way, the feeding and discharging can be continuous, the process of repeated heating and cooling is omitted, the time period is short, the heat utilization rate is high, and the fiber composite material can be continuously recovered.

[0066] Embodiment two

[0067] The present embodiment is a further improvement based on the first embodiment, and the main improvement is that, as shown in Figure 1 The conveyor belt 2 comprises:

[0068] a feeding side 21, a discharging side 22 and a central conveying part 23.

[0069] The height of the part of the central conveying part 23 supporting the material is greater than that of the feeding side 21.

[0070] The feeding side 21 and the discharging side 22 are respectively located on the two sides of the furnace body 1, and the central conveying part 23 is located inside the furnace body 1.

[0071] The superheated steam released by the air curtain device 4 has a high temperature. According to the principle of hot air rising, after being released, the superheated steam first moves downward at the initial speed at the time of release, and then moves upward after contacting the conveyor belt 2. And because the air pressure inside the furnace body 1 is less than the atmospheric pressure, the moving direction of the superheated steam after contacting the conveyor belt 2 is obliquely upward toward the furnace body 1. Therefore, in the present embodiment, the height of the part of the central conveying part 23 supporting the material is greater than that of the feeding side 21. Through such a setting, when the conveyor belt 2 transports the fiber composite material, the moving path of the fiber composite material is obliquely upward toward the furnace body 1, which coincides with the moving path of the superheated steam, so as to improve the utilization rate of the superheated steam and ensure the shielding effect of the air curtain.

[0072] Since the air curtain device 4 is located outside the furnace body 1, the superheated steam released by the air curtain device 4 will be released outside the furnace body 1. To prevent the superheated steam released by the air curtain device 4 from escaping outside the furnace body 1, thereby reducing superheated steam loss, this embodiment has made further improvements compared to the first embodiment. The improvements are as follows: Figure 1 As shown, the conveyor belt pyrolysis furnace also includes:

[0073] The feed pipe 11 and the discharge pipe 12 are respectively connected to the furnace body 1;

[0074] The conveyor belt 2 enters the furnace body 1 through the feed pipe 11 and then extends out of the furnace body 1 through the discharge pipe 12.

[0075] The feed pipe 11 and the discharge pipe 12 correspond to the feeding side and discharge side 22 of the conveyor belt 2, respectively, while the air curtain device 4 is correspondingly installed in the feed pipe 11 and the discharge pipe 12.

[0076] This explanation uses feed pipe 11 as an example. Figure 1 As shown, the feed pipe 11 has openings at both ends. One opening connects to the furnace body 1, and the other opening allows the conveyor belt 2 to enter the feed pipe 11 and then enter the furnace body 1 through the opening on the other side of the feed pipe 11. The air curtain device 4 is installed inside the feed pipe 11, and the air curtain formed by the release of superheated steam is located inside the feed pipe 11. By using the feed pipe 11 to enclose the feed side 21 and the air curtain, the superheated steam released by the air curtain is confined to a relatively enclosed space, which can prevent the superheated steam from escaping to the outside to a certain extent and reduce the loss of superheated steam.

[0077] In this embodiment, the feed pipe 11 has a first angle with the horizontal plane, and the first angle is in the range of 10° to 35°.

[0078] As can be seen from the above, the height of the material-supporting portion of the central conveyor 23 is greater than that of the feed side 21. This causes the feed side 21 to tilt upwards as a whole, meaning it forms an angle with the horizontal plane. Since the feed pipe 11 is positioned corresponding to the feed side 21, its tilt angle corresponds to that of the feed side 21. The angle between the feed side 21 and the horizontal plane is equal to the angle between the feed pipe 11 and the horizontal plane (i.e., the first angle).

[0079] The movement path of the fiber composite material (i.e., the conveying path of the feed side 21) is inclined upward towards the furnace body 1, which is the same as the movement path of the superheated steam. The movement path of the superheated steam is related to both the temperature of the superheated steam and the gas pressure inside the furnace body 1.

[0080] Since superheated steam is used to heat fiber composite materials to induce a pyrolysis reaction, and different types of fiber composite materials undergo pyrolysis at different temperatures, the temperature of the superheated steam is determined by the type of fiber composite material. That is, when recycling the same type of fiber composite material, the temperature of the superheated steam is fixed. Therefore, when recycling the same type of fiber composite material, the movement path of the superheated steam can be determined by the gas pressure inside furnace 1.

[0081] In this conveyor belt pyrolysis furnace, the internal pressure of the furnace body 1 is mainly determined by the following factors: 1. the gas flow rate of the pyrolysis gas extraction device 3; 2. the total amount of pyrolysis gas produced by the pyrolysis reaction within the furnace body 1; and 3. the flow rate of superheated steam. During the pyrolysis reaction, the total amount of pyrolysis gas produced by the pyrolysis reaction within the furnace body 1 is constant. Therefore, when it is necessary to maintain the internal pressure of the furnace body 1 within a certain range, the greater the flow rate of superheated steam, the greater the gas flow rate of the pyrolysis gas extraction device 3. The insulation effect of the air curtain device 4 is directly proportional to the flow rate of superheated steam; that is, the greater the flow rate of superheated steam, the better the insulation effect of the air curtain.

[0082] Therefore, after comprehensively considering all the above factors and through multiple experimental adjustments by the applicant, the optimal first included angle is within the range of 10° to 35°. At this angle, the movement path of the fiber composite material coincides with the movement path of the superheated steam, the flow rate of the superheated steam is relatively small, and the isolation effect of the air curtain is good. While meeting the requirements for the pyrolysis reaction of the fiber composite material, this effectively saves on the amount of superheated steam used, avoids waste, and conserves energy.

[0083] In this embodiment, as Figure 1 and Figure 3 As shown in the figure, the air curtain device 4 includes an air inlet air curtain mechanism 41, which is disposed in the feed pipe 11;

[0084] The air intake curtain mechanism 41 includes a plurality of air curtain nozzles 42, which release superheated steam in the direction of the conveyor belt 2 to generate an air curtain and heat the fiber composite material.

[0085] Specifically, multiple air curtain nozzles 42 are evenly arranged along the width direction of the conveyor belt 2, and the arrangement direction is perpendicular to the moving direction of the conveyor belt 2. Moreover, in order to ensure the isolation effect of the air curtain, in this embodiment, the multiple air curtain nozzles 42 are spaced out in at least two rows along the moving direction of the conveyor belt, and the air jet directions of the air curtain nozzles 42 in adjacent rows are staggered.

[0086] It should be noted that the jet directions of the air curtain nozzles 42 are staggered, meaning that the extensions of the directions have an included angle. By means of the air curtain group whose jet direction is toward the side of the furnace body 1, the gas inside the furnace body 1 can be better isolated, and leakage of the gas inside the furnace body 1 to the outside can be prevented. Conversely, by means of the air curtain group whose jet direction is toward the side of the outside, the outside air can be better isolated, and entry of the outside air into the furnace body 1 can be prevented.

[0087] In addition, in order to further avoid leakage of the overheated steam and the cracking gas inside the furnace body 1, an anti-leakage pipeline 16 is further arranged on the side of the air curtain mechanism close to the outside of the feeding pipeline 11. The anti-leakage pipeline is provided with a valve 17 and is connected to the cracking gas exhaust device 3 or other negative pressure generating device. When the overheated steam or the cracking gas leaks, the valve 17 can be opened, and the anti-leakage pipeline 16 can be used for exhaust, so as to avoid leakage of the cracking gas and the overheated steam.

[0088] It should be noted that in the embodiment, the air curtain device 4 can further include an air outlet air curtain mechanism arranged in the discharging pipeline 12, and the specific structure can be similar or identical to that of the air inlet air curtain mechanism 41.

[0089] In addition, in the embodiment, a water cooling device 15 can be arranged in the discharging pipeline 12, which is used for cooling the pyrolyzed fibers and reducing the temperature of the fibers so that the fibers can be directly oxidized. Specifically, the water cooling device 15 can include a cooling pipe which surrounds or is inserted into the discharging pipeline 12, so as to absorb the heat of the pyrolyzed fibers. By cooling the fibers, combustion of the fibers during oxidation of the residual carbon can be prevented, and the carbon removal reaction can be more accurate.

[0090] Embodiment Three

[0091] During use of the second embodiment, the applicant found that the overheated steam released outside the furnace body 1 can be in contact with the outside air, which can affect the temperature of the overheated steam, and after entering the furnace body 1, the temperature inside the furnace body 1 can not reach the set temperature, which can affect the pyrolysis reaction inside the furnace body 1.

[0092] Therefore, the third embodiment is further improved based on the second embodiment, and the improvement is that, as shown in Figure 1 The conveying belt type pyrolysis furnace further includes a cracking pipeline 13 arranged in the furnace body 1.

[0093] Two ends of the cracking pipeline 13 are connected to the feeding pipeline 11 and the discharging pipeline 12, respectively.

[0094] The conveying belt 2 passes through the cracking pipeline 13, and the fiber composite material is cracked in the cracking pipeline 13.

[0095] The cracking pipeline 13 has a heating cavity 5 between the furnace body 1, and the cracking gas extraction device 3 is connected with the cracking pipeline 13 through the heating cavity 5.

[0096] The auxiliary heating device is arranged in the heating cavity 5.

[0097] The cracking pipeline 13 is located in the furnace body 1 and corresponds to the central conveying part 23 of the conveying belt 2, and serves as a cracking cavity for pyrolysis reaction of the fiber composite material. The fiber composite material enters the cracking pipeline 13 in the furnace body 1 through the feeding pipeline 11 under the conveying action of the conveying belt 2, and performs pyrolysis reaction in the cracking pipeline 13, and then is discharged from the discharging pipeline 12 at the other end of the furnace body 1.

[0098] The auxiliary heating device arranged in the heating cavity 5 can heat the cracking pipeline 13 outside the cracking pipeline 13, and then heat the fiber composite material inside the cracking pipeline 13 during the pyrolysis reaction of the fiber composite material in the cracking pipeline 13 in the furnace body 1. On the basis of superheated steam as the main heat source, the auxiliary heating device can assist in heating the fiber composite material as an auxiliary heat source to ensure that the temperature inside the cracking pipeline 13 reaches the set temperature for pyrolysis reaction of the fiber composite material, and ensure that the pyrolysis reaction proceeds normally.

[0099] Specifically, the auxiliary heating device comprises:

[0100] A heat source inlet 51 passes through the outer wall of the furnace body 1 and is connected with the heating cavity 5, and is used for introducing high-temperature gas into the heating cavity 5 to heat the cracking pipeline 13;

[0101] A heat source outlet 52 passes through the outer wall of the furnace body 1 and is connected with the heating cavity 5, and is used for discharging the high-temperature gas.

[0102] Through the arrangement of the heat source inlet 51 and the heat source outlet 52, the high-temperature gas flows in the heating cavity 5, and the high-temperature gas is used for auxiliary heating of the cracking pipeline 13.

[0103] In addition, in the embodiment, the auxiliary heating device can further comprise:

[0104] An electric heating assembly 6 is arranged on the inner wall of the furnace body 1 and can heat at least part of the cracking pipeline 13;

[0105] A temperature sensor is used for measuring the temperature in the cracking pipeline 13, and the temperature sensor is in communication connection with the electric heating assembly 6.

[0106] Specifically, a plurality of electric heating assemblies 6 can be arranged in the plurality of regions inside the furnace body 1 respectively, and correspond to a part of the cracking pipelines 13 respectively, so as to divide the cracking pipelines 13 into a plurality of temperature control regions. Each electric heating assembly 6 corresponds to a temperature control region, and a temperature sensor is arranged in each temperature control region respectively to measure the temperature in the corresponding temperature control region. In actual application, the temperature of each temperature control region can be monitored in real time by the temperature sensor, and the corresponding temperature control region can be heated by the electric heating assembly 6 as needed, so as to better ensure the uniformity of the temperature inside the cracking pipelines 13 and realize local temperature control.

[0107] The pyrolysis reaction of the same component at different temperatures will produce different cracking gases. In addition, the pyrolysis reaction of different components at different temperatures will produce different cracking gases. Based on the above two points, the skilled person can control the pyrolysis reaction to a certain extent, such as controlling the type of cracking gas produced by the pyrolysis reaction and controlling the component for the pyrolysis reaction, by adjusting the temperature of the local region by the point heating assembly according to the needs.

[0108] Embodiment Four

[0109] This embodiment is a further improvement based on Embodiment Three, and the improvement is that: Figure 1 and Figure 2 In combination with the illustration, the conveyor-type cracking furnace comprises:

[0110] A cracking gas outlet 7 is arranged on the furnace body 1 and communicates with the cracking pipelines 13, and is used to release the cracking gas.

[0111] A pressure controller is connected with the cracking gas outlet 7 and adjusts the gas pressure in the cracking pipelines 13 by controlling the gas flow of the cracking gas outlet 7.

[0112] The pressure controller is used to control the gas flow of the cracking gas outlet 7 to adjust the pressure in the cracking pipelines 13, so that the pressure inside the cracking pipelines 13 is less than the atmospheric pressure, and the cracking pipelines 13 are in a state of micro-negative pressure. Since the cracking pipelines 13 are in a state of micro-negative pressure, the pressure inside the cracking pipelines 13 is less than the atmospheric pressure, and the cracking gas in the cracking pipelines 13 is difficult to leak to the outside, thereby preventing pollution and waste and ensuring production safety. The pressure inside the cracking pipelines 13 is mainly affected by the superheated steam injected into the cracking pipelines 13 and the cracking gas produced by the pyrolysis reaction, so as long as the gas flow of the cracking gas outlet 7 is greater than the gas flow of the superheated steam and the total amount of the cracking gas produced by the pyrolysis reaction per unit time, the pressure inside the cracking pipelines 13 can be ensured.

[0113] In this embodiment, the pressure controller comprises:

[0114] a pressure sensor arranged in the cracking pipe 13 and detecting the pressure in the cracking pipe 13;

[0115] a fan 8 connected in communication with the pressure sensor, the fan 8 being arranged opposite the cracking gas outlet 7;

[0116] a pressure relief pipe 9 connected to the cracking gas outlet 7, the fan 8 being arranged in the pressure relief pipe 9, and the blowing direction of the fan 8 being directed toward the direction of the cracking gas outlet 7;

[0117] a one-way valve 10 arranged in the pressure relief pipe 9.

[0118] In this embodiment, the fan 8 is arranged in the cracking gas outlet 7 and blows toward the outside of the cracking pipe 13. The pressure sensor arranged in the cracking pipe 13 detects the pressure in the cracking pipe 13 and compares the detected pressure in the cracking pipe 13 with the outside pressure. According to the comparison result, the speed of the fan 8 is controlled to control the gas flow rate of the cracking gas outlet 7, thereby adjusting the pressure in the cracking pipe 13, so that the pressure in the cracking pipe 13 is slightly lower than the outside pressure, and the cracking pipe 13 is in a state of slight negative pressure.

[0119] It should be noted that the pressure relief pipe 9 can be a conveying pipe for conveying the gas in the cracking pipe 13 to other locations, or a bypass pipe connected in parallel to the conveying pipe. The bypass pipe can be connected to a temporary gas storage device. In this embodiment, as shown in Figure 2 the pressure relief pipe 9 is a conveying pipe for conveying the reaction gas to other locations, and the fan 8 is directly arranged in the conveying pipe.

[0120] In addition, the gas flow direction of the one-way valve 10 is the direction of conveying the gas from the cracking pipe 13 to the outside, which can ensure the smooth conveying of the gas in the cracking pipe 13 to the outside, and can also avoid the problem of excessive pressure in the furnace caused by the reverse conveying of the gas into the cracking pipe 13 due to the gas pressure.

[0121] It is obvious to those skilled in the art that the present application is not limited to the details of the above-described exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application. Therefore, the embodiments should be regarded as exemplary and non-limiting, and the scope of the present application is defined by the appended claims rather than the above description, and all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present application. Any reference signs in the claims should not be regarded as limiting the claims involved.

Claims

1. A conveyorized pyrolysis oven for pyrolyzing fiber composite material, characterized by, The application relates to a pyrolysis device for pyrolyzing fiber composite materials, which comprises the following parts: a furnace body and a conveyor belt arranged through the furnace body; a pyrolysis gas extraction device arranged on the furnace body and used for extracting pyrolysis gas generated by pyrolyzing the fiber composite materials in the furnace body; an air curtain device arranged at the inlet and outlet of the conveyor belt, which is used for releasing superheated steam with an oxygen content of less than or equal to 0.3% and a temperature of 400-700 DEG C to generate an air curtain and heat the fiber composite materials; the air curtain device comprises a plurality of air curtain nozzles, the air curtain nozzles are arranged in at least two rows along the moving direction of the conveyor belt, and the air jet directions of the air curtain nozzles in the adjacent two rows are staggered with each other; the device further comprises a feeding pipe connected to the furnace body; the conveyor belt enters the furnace body through the feeding pipe, the feeding pipe has a first included angle with the horizontal plane, and the first included angle is in the range of 10 DEG to 35 DEG.

2. The conveyor belt pyrolysis furnace of claim 1, wherein the conveyor belt comprises: a feeding side, a discharging side and a central conveying part; the height of the part of the central conveying part supporting the materials is greater than that of the feeding side.

3. The conveyor belt pyrolysis furnace of claim 2, wherein the device further comprises: a discharging pipe connected to the furnace body; the conveyor belt extends out of the furnace body through the discharging pipe.

4. The conveyor belt pyrolysis furnace of claim 3, wherein the air curtain device further comprises: an air inlet air curtain mechanism arranged in the feeding pipe; the air curtain nozzles release the superheated steam to generate the air curtain and heat the fiber composite materials in the direction of the conveyor belt.

5. The conveyorized cracking furnace of claim 3, wherein, the device further comprises a pyrolysis pipe arranged in the furnace body; two ends of the pyrolysis pipe are connected with the feeding pipe and the discharging pipe respectively; the conveyor belt passes through the pyrolysis pipe, and the fiber composite materials are pyrolyzed in the pyrolysis pipe; the pyrolysis pipe and the furnace body have a heating cavity, the pyrolysis gas extraction device passes through the heating cavity and is connected with the pyrolysis pipe; the heating cavity is provided with an auxiliary heating device.

6. The conveyor belt pyrolysis furnace of claim 5, wherein, the auxiliary heating device comprises: a heat source inlet passing through the outer wall of the furnace body and connected with the heating cavity, which is used for introducing high-temperature gas into the heating cavity to heat the pyrolysis pipe; a heat source outlet passing through the outer wall of the furnace body and connected with the heating cavity, which is used for discharging the high-temperature gas.

7. The conveyor belt type cracker furnace according to claim 6, characterized in that, the auxiliary heating device further comprises: an electric heating assembly arranged on the inner wall of the furnace body and capable of heating at least part of the pyrolysis pipe; a temperature sensor used for measuring the temperature in the pyrolysis pipe, which is communicatively connected with the electric heating assembly.

8. The conveyor belt pyrolysis furnace according to any one of claims 5 to 7, characterized in that, the pyrolysis gas extraction device comprises: a pyrolysis gas outlet arranged on the furnace body and in communication with the pyrolysis pipe, which is used for releasing the pyrolysis gas; a pressure controller connected with the pyrolysis gas outlet and used for adjusting the gas pressure in the pyrolysis pipe by controlling the gas flow of the pyrolysis gas outlet.

9. The conveyor belt type cracking furnace according to claim 8, characterized in that, the pressure controller comprises: a pressure sensor arranged in the pyrolysis pipe and used for detecting the pressure in the pyrolysis pipe; a fan communicatively connected with the pressure sensor, which is arranged opposite to the pyrolysis gas outlet; a pressure relief pipe connected with the pyrolysis gas outlet, the fan is arranged in the pressure relief pipe, and the blowing direction of the fan is toward the direction of the pyrolysis gas outlet; a one-way valve arranged in the pressure relief pipe.

Images