An internal heat type thermal conversion apparatus and method

Abstract

The embodiment of the present application provides an internal heating type thermal conversion device, which comprises a spiral feeding system, a microwave generating system and a heating ball and the like. The raw material is fully mixed with the heating ball under the agitation and pushing of the spiral blade, and is heated and continuously passes through different reaction sections under the microwave action, and sequentially occurs dehydration, pyrolysis and gasification reactions at the most suitable temperature; a large amount of gas generated sharply automatically passes through the gas permeable partition under the self expansion pressure and is discharged through the corresponding guide system; the water vapor generated by the dehydration of the raw material further participates in the gasification reaction, eliminates harmful components and produces high value gasification gas, and the pyrolysis gas is separated and condensed to obtain high value liquid phase products. The device has the advantages of concentrated heating, fast response to control, puffing raw material, automatic exhaust, clean discharge, high space utilization rate, and can realize efficient pyrolysis and gasification process through precise temperature control. The embodiment of the present application also provides a thermal conversion method beneficial to the internal heating type thermal conversion device.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of harmless treatment of organic solid waste, and particularly relates to an internal heating type thermal conversion device. The present application also provides a thermal conversion method using the internal heating type thermal conversion device. BACKGROUND

[0002] Thermal conversion includes pyrolysis, gasification, etc., wherein pyrolysis is a high-efficiency means for treating organic solid waste (organic solid waste) such as biomass, household garbage, waste plastics, waste rubber, etc., and has advantages such as short treatment period, high conversion efficiency, obvious volume reduction effect, efficient solidification of heavy metals, and avoidance of generation of harmful substances such as dioxin, compared with traditional treatment methods, while simultaneously obtaining solid, liquid and gas products, and further preparing high-value chemicals or fuels. As a solid product, pyrolysis carbon / semi-coke is not easy to burn, and through gasification technology, it can be further converted into high-value gasification gas, which can be used for fuel cell power generation, etc., to improve the resource utilization rate of organic solid waste. Therefore, pyrolysis and gasification are technologies with extremely promising application and promotion prospects in the process of harmless disposal and high-value utilization of organic solid waste.

[0003] A screw reactor is a high-efficiency pyrolysis device, which usually uses wall heating or solid heat carriers for heat exchange, relies on the shaft with spiral blades to rotate in the closed pipe wall to gradually push the raw material forward, and realizes continuous pyrolysis or gasification. Compared with other pyrolysis devices such as fixed bed and fluidized bed, it has advantages such as controllable stages, continuous operation, and low heat loss. However, pure wall heat transfer from the outside to the inside can easily lead to uneven temperature distribution. Even if solid heat carriers are used for auxiliary heat exchange, due to the gradual decrease of the heat storage capacity of the heat carriers themselves, the temperature will gradually decrease along the axial direction of the screw pipe, and it is also difficult to stably maintain high-efficiency reaction. At the same time, for these traditional heat transfer methods, due to the large thermal inertia of the device, the response of the control is very slow, and it is difficult to flexibly control the temperature according to the changes in the composition of the raw material and the reaction stage, and it is impossible to effectively combine the pyrolysis and gasification processes.

[0004] In order to effectively control the temperature and other working conditions, conventional pyrolysis and gasification devices adopt a double-chamber structure. The pyrolysis and gasification devices disclosed in Chinese patent documents CN104789245A and CN105441138A can carry out the pyrolysis and gasification processes of the raw material and the gasification process of the pyrolysis carbon / semi-coke, respectively, through the interconnection of the pyrolysis chamber and the gasification chamber, and through precise control of the temperature and other reaction conditions, high-efficiency pyrolysis and gasification processes can be realized, respectively. For the segmented pyrolysis and gasification device disclosed in Chinese patent document CN107903948A, a plurality of screw pyrolysis and gasification furnaces are connected in series, which is conducive to the temperature control to adapt to the changes in the working conditions of the actual reaction process and improve the pyrolysis and gasification efficiency. However, the design of separating these different reaction chambers will lead to a complex and large device structure, and the operation of multiple rotating parts at high temperature makes it difficult to effectively seal the device, which is not conducive to the popularization and application of the technology.

[0005] In view of the deficiencies of the prior art, it is urgent to develop a new pyrolysis gasification device that can timely respond to and control the pyrolysis and gasification processes to achieve the best working condition under the premise of compact structure and efficient heat transfer. SUMMARY

[0006] The technical problem to be solved by the present application is the uneven heat transfer, low space utilization, inability to timely respond to and control, difficulty in effective sealing, and inability to effectively carry out the pyrolysis and gasification processes of the existing pyrolysis gasification device, and an internal heat type heat conversion device and heat conversion method are provided, which can realize timely control of the pyrolysis and gasification processes by precise temperature control under the premise of compact structure and efficient heat transfer, so as to maintain the best working condition.

[0007] To solve the above technical problems, an embodiment of the present application provides an internal heat type heat conversion device, which comprises a spiral feeding system and a microwave generating system, the spiral feeding system comprises a spiral pipe, a rotating shaft, a spiral blade and a driver; wherein:

[0008] The spiral pipe is a hollow circular pipe arranged obliquely, and is filled with heat generating balls inside, the spiral pipe is sequentially provided with a feeding section, a dehydration section, a pyrolysis section, a gasification section and a discharging section from a lower end to a higher end, and adjacent sections are separated by sealing areas, the dehydration section, the pyrolysis section and the gasification section belong to high-temperature reaction sections; the rotating shaft is coaxially arranged in the spiral pipe; the feeding section is provided with a feeding port at the top for feeding raw materials, and the discharging section is provided with a discharging device at the bottom; the discharging device is connected to the feeding section through a return pipe, the heat generating balls separated from the inorganic waste residues are cooled and returned to the feeding section through the return pipe, and the inorganic waste residue discharge port of the discharging device can be connected to a solid collection system to realize inorganic waste residue collection.

[0009] A water vapor guiding unit is connected to the upper opening of the dehydration section for discharging water vapor, a pyrolysis gas guiding unit is connected to the upper opening of the pyrolysis section for discharging pyrolysis gas, and a gasification gas guiding unit is connected to the upper opening of the gasification section for discharging gasification gas; the exhaust port of the pyrolysis gas guiding unit can be connected to a liquid collection system through a separation and condensation system to realize pyrolysis gas collection; and the exhaust port above the gasification gas guiding unit can be connected to a gas collection system.

[0010] The rotating shaft is penetrated by the feeding section to the discharging section, the helical blade is continuously fixed around the rotating shaft, and the driver is connected and drives the rotating shaft to rotate; the sealing piece is installed on the edge of the helical blade in the sealing area, and the sealing piece is in close contact with the inner wall of the helical pipe to form a seal; the rotating shaft is a hollow shaft in the gasification section and the discharging section, and a gasification agent channel is arranged in the hollow shaft, the gasification agent channel is connected with the exhaust port of the water vapor guiding unit, and a plurality of gas outlets communicating with the gasification agent channel are arranged on the inner surface of the rotating shaft in the gasification section for releasing the gasification agent.

[0011] The microwave generating system comprises a plurality of microwave generators; the dehydration section, the pyrolysis section and the gasification section are respectively arranged with a plurality of microwave generators on both sides of the middle part for emitting microwaves into the helical pipe.

[0012] Preferably, the heat generating ball is composed of a wave-absorbing material that absorbs microwaves of a specific frequency emitted by the microwave generator. Further preferably, a wear-resistant layer is arranged on the surface of the heat generating ball.

[0013] Preferably, the width of the sealing area is not less than the pitch of one helical blade.

[0014] As a preferred embodiment of the above technical scheme, the water vapor guiding unit, the pyrolysis gas guiding unit and the gasification gas guiding unit all comprise a hollow box body, the dehydration section is communicated with the box cavity of the water vapor guiding unit through a first air-permeable partition plate, the pyrolysis section is communicated with the box cavity of the pyrolysis gas guiding unit through a second air-permeable partition plate, and the gasification section is communicated with the box cavity of the gasification gas guiding unit through a third air-permeable partition plate.

[0015] The application also provides a method for utilizing the above-mentioned internal heating type heat conversion device, which is characterized by comprising the following steps:

[0016] Step 1. Start the driver to drive the helical blade to rotate and push the heat generating ball in the helical pipe to move from the feeding section to the discharging section; start the microwave generator to emit microwaves of a specific frequency and power into the dehydration section, the pyrolysis section and the gasification section of the helical pipe respectively, heat the heat generating ball by the microwaves, and maintain the set drying temperature, pyrolysis temperature and gasification temperature;

[0017] Step 2. The raw material is sent into the feeding section through the feeding port, and the raw material and the heat generating ball are fully mixed by the stirring and pushing of the helical blade, and then enter the dehydration section;

[0018] Step 3. The raw material is heated rapidly and the water is removed rapidly in the dehydration section, and the generated water vapor enters the water vapor guiding unit through the first air-permeable partition plate under the action of pressure, and then enters the gasification agent channel;

[0019] Step 4. After dehydration, the raw material enters the pyrolysis section to be pyrolyzed, and the generated pyrolysis gas passes through the second gas-permeable partition under the action of pressure to enter the pyrolysis gas guiding unit, is separated and condensed, and then is discharged and the liquid product is collected, and the remaining residual carbon enters the gasification section;

[0020] Step 5. In the gasification section, the gasification agent in the gasification agent channel is released through the gas outlet and fully mixed with the residual carbon to generate a gasification reaction, and the generated gasification gas passes through the third gas-permeable partition under the action of pressure to enter the gasification gas guiding unit, is discharged and the gasification gas is collected;

[0021] Step 6. After gasification, the remaining inorganic waste residue is discharged and collected after the heat-generating ball is separated in the discharging device; the separated heat-generating ball is cooled through the return pipe and is re-fed into the feeding section of the spiral pipe to continue to participate in the circulation.

[0022] The core of the internal heating type thermal conversion device in the technical scheme is the three high-temperature reaction sections continuously arranged in the same spiral pipe, the different reaction sections are separated by the sealing area, the water vapor is harmlessly treated in the gasification section, the temperature is effectively controlled by using the microwave generator and the heat-generating ball, and the gas is automatically discharged under the expansion by using the guiding unit. The raw material enters the internal heating type thermal conversion device from the feeding section, is agitated and pushed by the spiral blade, and is fully mixed with the heat-generating ball; under the action of the microwave generator, the raw material is heated by the heat-generating ball or directly absorbs microwave energy to rapidly increase the temperature, continuously passes through the different reaction sections separated by the sealing area, and sequentially undergoes the dehydration, pyrolysis and gasification processes at the most suitable temperature; a large amount of gas generated in the three high-temperature reaction sections automatically passes through the gas-permeable partition under the action of the self-expansion pressure and is discharged through the corresponding guiding unit; the water vapor generated by the dehydration of the raw material is further sent into the gasification section to participate in the reaction as part of the gasification agent, the harmful components are eliminated, and the high-value gasification gas is produced; the pyrolysis gas is separated and condensed, and the high-value liquid phase product is collected; finally, the inorganic waste residue and the heat-generating ball are separated after the pyrolysis and gasification, and the heat-generating ball is discharged and returned to the feeding section to participate in the circulation.

[0023] The beneficial effects of the above technical scheme of the embodiment of the present application are as follows:

[0024] 1. Fast heating rate and high energy efficiency: Without the heat conduction process from the outside to the inside, the device can well penetrate the device, directly act on the raw material and the heat-generating ball, be directly absorbed by the raw material molecules or the wave-absorbing material to increase the temperature, the heating rate is fast, the thermal gradient is small, the reaction period can be shortened, and the heat loss of other structures of the device is small, so that the energy consumption can be saved.

[0025] 2. Selectivity, heat concentration: Microwave of specific frequency can only be absorbed by special raw material molecules or wave-absorbing materials, and the heating range is concentrated, so it is easy to control the temperature of different reaction stages, and the optimal working conditions of dehydration, pyrolysis, gasification and other processes are realized, and the reaction efficiency is high. In the spiral pyrolysis reactor, the high temperature is concentrated in the reaction section, avoiding high temperature in the feeding area, so that the raw materials are not easy to soften and bond when feeding.

[0026] 3. Small thermal inertia, fast response: Microwave of specific frequency can only heat the heat generating ball composed of raw material molecules or wave-absorbing materials, and the device has little residual heat, so the thermal inertia is small, there is no thermal hysteresis effect, the temperature can be adjusted in time and the device can be started and stopped quickly, the state of the reaction process in different areas can be changed flexibly, and the temperature can be compensated by the heat generating ball, so that the temperature remains stable and the heat is evenly transmitted when the composition of the raw materials changes.

[0027] 4. Swelling and loosening are beneficial to reaction: Microwave can directly heat the internal components of the raw materials, rapidly raise the temperature to generate a large amount of gas, form many small pores, make the raw materials swell and become loose, prevent sticking or accumulation, ensure stable operation of the equipment, and facilitate the full action of the subsequent gasification agent.

[0028] 5. Convenient reaction control and wide raw material adaptability: By controlling the feeding speed of the device, the circulating amount of the heat generating ball, the microwave emission power and frequency of different reaction stages, and the rotating speed of the rotating shaft, the reaction temperature, reaction time and reaction mode of different processes can be flexibly adjusted, so that the pyrolysis and gasification reactions can be controlled according to different raw materials and target products, and efficient conversion can be realized. In addition, microwave can penetrate into the raw materials and heat them evenly, and the requirements for the size and shape of the raw materials are low. At the same time, the collision and friction of the heat generating ball can also break the raw materials, which can reduce the power consumption of the crushing pretreatment.

[0029] 6. Clean emission and high resource utilization rate: Pyrolysis is an oxygen-free process that 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 dioxin from the source, and achieve effective dechlorination of the raw materials. At the same time, the water vapor generated in the dehydration stage of the raw materials is further used as a gasification agent to participate in the gasification reaction of the pyrolysis carbon, eliminating harmful components carried by the dehydration process, and producing gasification gas rich in CH4, H2 and CO, thereby improving the resource utilization rate of the raw materials.

[0030] 7. Automatic exhaust, safe operation: The spiral device has a compact space and strong pressure resistance, and the spiral blade with a sealing sheet can effectively seal the spiral pipe to prevent gas overflow, so that the water vapor, pyrolysis gas and gasification gas can directly enter the corresponding guide system through the gas permeable partition when they expand rapidly, realizing automatic exhaust, instead of remaining in the spiral pipe to cause pipe blockage and equipment damage.

[0031] 8. Compact structure, easy to seal: The additional heat exchange, water vapor purification and other auxiliary equipment are omitted, different reaction sections are arranged in the same spiral pipe, the device volume corresponding to a unit of raw material is small, the structure is compact, the space utilization rate is high; in addition, the rotating parts of the device are few and not directly heated, the temperature is lower, which helps to improve the sealing of the whole device. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 Front view of the internal heating type thermal conversion device provided by the embodiment of the present application;

[0033] Figure 2 Cross-sectional view of the internal heating type thermal conversion device shown in Figure 1

[0034] Figure 3 Step flow chart of the thermal conversion method provided by the embodiment of the present application.

[0035] [Explanation of main element symbols]

[0036] 1- Spiral pipe; Z1- Feed section; Z2- Dehydration section; Z3- Pyrolysis section; Z4- Gasification section; Z5- Discharge section; ZR- Sealing area; 11- Feed inlet; 12- Discharge device;

[0037] 2- Rotating shaft; 21- Gasification agent channel; 211- Gas outlet hole; 22- Spiral blade; 221- Sealing piece;

[0038] 3- Driver;

[0039] 4- Water vapor guiding unit; 41- First gas-permeable partition;

[0040] 5- Pyrolysis gas guiding unit; 51- Second gas-permeable partition;

[0041] 6- Gasification gas guiding unit; 61- Third gas-permeable partition;

[0042] 7- Heat generating ball;

[0043] 8- Return pipe;

[0044] 9- Microwave generator. DETAILED DESCRIPTION

[0045] In order to make the technical problems, technical solutions and advantages to be solved by the present application clearer, the following will be described in detail in combination with the drawings and specific embodiments. The examples of the embodiments are shown in the drawings, wherein the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are intended to explain the present application, and cannot be understood as a limitation of the present application.

[0046] ​The present application aims at the existing problems, and provides an internal heating type heat conversion device and method, which has the characteristics of fast heating rate, heat concentration, good selectivity, fast response for regulation and control, puffing raw materials, automatic exhaust, good sealing, high space utilization, wide raw material adaptability, high resource utilization, clean emission and the like, and can realize efficient pyrolysis and gasification through precise temperature control.

[0047] In order to realize the above technical scheme, as shown in Figure 1 and Figure 2 , the embodiment of the present application provides an internal heating type heat conversion device, which comprises a spiral feeding system and a microwave generating system, the spiral feeding system comprises a spiral pipe 1, a rotating shaft 2, spiral blades 22 and a driver 3; wherein:

[0048] The spiral pipe 1 is a hollow circular pipe arranged obliquely, and the inside of the spiral pipe 1 is filled with heating balls 7. As a better embodiment, the heating balls 7 are composed of wave-absorbing materials that can absorb specific frequency microwaves emitted by a microwave generator 9. If wear-resistant silicon carbide is used as the wave-absorbing material, the wave-absorbing frequency is 12-18GHz, and the optimal frequency is 15GHz, then the emission frequency of the corresponding microwave generator 9 can be set to 15GHz; a wear-resistant layer can also be arranged on the surface of the heating ball 7. The spiral pipe 1 is sequentially provided with a feeding section Z1, a dehydration section Z2, a pyrolysis section Z3, a gasification section Z4 and a discharging section Z5 from a lower end to a higher end, and adjacent sections are separated by a sealing zone ZR. In order to realize better segmentation, the width of the sealing zone ZR is not less than the pitch of one spiral blade 22; the dehydration section Z2, the pyrolysis section Z3 and the gasification section Z4 belong to high-temperature reaction sections; the rotating shaft 2 is coaxially arranged in the spiral pipe 1; the top of the feeding section Z1 is provided with a feeding port 11 for feeding raw materials; the bottom of the discharging section Z5 is provided with a discharging device 12; the discharging device 12 is connected to the feeding section Z1 through a return pipe 8, the heating balls 7 separated from the inorganic waste residue are cooled in the return pipe 8, and then returned to the feeding section Z1 through the return pipe 8; the inorganic waste residue discharge port of the discharging device 12 can be connected to a solid collection system to realize inorganic waste residue collection.

[0049] The water vapor guiding unit 4 is connected to the upper opening of the dewatering section Z2 for discharging water vapor, the pyrolysis gas guiding unit 5 is connected to the upper opening of the pyrolysis section Z3 for discharging pyrolysis gas, and the gasification gas guiding unit 6 is connected to the upper opening of the gasification section Z4 for discharging gasification gas; the exhaust port of the pyrolysis gas guiding unit 5 can be connected to the liquid collecting system through the separation and condensation system to realize the collection of pyrolysis gas; and the exhaust port above the gasification gas guiding unit 6 can be connected to the gas collecting system. As a better embodiment, the water vapor guiding unit 4, the pyrolysis gas guiding unit 5 and the gasification gas guiding unit 6 all comprise a hollow box body, the dewatering section Z2 is connected to the box cavity of the water vapor guiding unit 4 through the first air-permeable partition plate 41, the pyrolysis section Z3 is connected to the box cavity of the pyrolysis gas guiding unit 5 through the second air-permeable partition plate 51, and the gasification section Z4 is connected to the box cavity of the gasification gas guiding unit 6 through the third air-permeable partition plate 61.

[0050] The rotating shaft 2 penetrates through the feeding section Z1 to the discharging section Z5, the helical blade 22 is continuously fixed around the rotating shaft 2, and the driver 3 is connected to and drives the rotating shaft 2 to rotate; the sealing sheet 221 is mounted on the edge of the helical blade 22 in the sealing zone ZR, and the sealing sheet 221 is attached to the inner wall of the helical pipe 1 to form a seal; the rotating shaft 2 is a hollow shaft in the gasification section Z4 and the discharging section Z5, and the gasification agent channel 21 is arranged in the rotating shaft 2, the gasification agent channel 21 is connected to the exhaust port of the water vapor guiding unit 4, and a plurality of gas outlets 211 are arranged on the inner surface of the rotating shaft 2 in the gasification section Z4 and connected to the gasification agent channel 21 for releasing the gasification agent.

[0051] The microwave generating system comprises a plurality of microwave generators 9; the dewatering section Z2, the pyrolysis section Z3 and the gasification section Z4 are each arranged with a plurality of microwave generators 9 on both sides of the middle part for emitting microwaves into the helical pipe 1.

[0052] In order to better realize the above technical scheme, the application further provides a method for using the internal heating type thermal conversion device as shown in Figure 3 The method comprises the following steps:

[0053] S1. Start the driver to drive the helical blade to rotate and push the heat generating balls in the helical pipe to move from the feeding section to the discharging section; start the microwave generator to emit microwaves with specific frequency and power into the dewatering zone, the pyrolysis zone and the gasification zone of the helical pipe respectively, heat the heat generating balls by the microwaves, and maintain the set drying temperature, pyrolysis temperature and gasification temperature;

[0054] S2. The raw material is sent into the feeding section through the feeding port, and is fully mixed with the heat generating balls by the stirring and pushing of the helical blade and then enters the dewatering section;

[0055] S3. The raw material is heated rapidly and the water is removed rapidly in the dewatering section, and the generated water vapor enters the water vapor guiding unit through the first air-permeable partition plate under the action of pressure and then enters the gasification agent channel;

[0056] S4. After the raw material is dehydrated, it enters the pyrolysis section to undergo pyrolysis, and the pyrolysis gas generated under the action of pressure passes through the second gas-permeable partition into the pyrolysis gas guiding unit, is discharged and liquid products are collected after separation and condensation, and the remaining residual carbon enters the gasification section;

[0057] S5. In the gasification section, the gasification agent in the gasification agent channel is released through the gas outlet and fully mixed with the residual carbon to undergo a gasification reaction, and the gasification gas generated under the action of pressure passes through the third gas-permeable partition into the gasification gas guiding unit, is discharged and the gasification gas is collected;

[0058] S6. After gasification, the remaining inorganic waste residue is discharged and collected after the heat-generating balls are separated out in the discharging device; the separated heat-generating balls are cooled through the return pipe and are re-fed into the feeding section of the spiral pipe to continue to participate in the circulation.

[0059] The process flow of organic solid waste raw material pyrolysis and gasification using an internal heating type heat conversion device is described in detail below through specific examples, and the devices used in each example have basically the same structure.

[0060] Example 1

[0061] In the embodiment, the spiral pipe 1 is a hollow circular pipe arranged at an inclination of 15°, with a diameter of 200 mm; the spiral pipe 1 has a rotating shaft 2 coaxially arranged inside, with a diameter of 80 mm; the spiral pipe 1 is divided into sequentially connected feeding section Z1, dehydration section Z2, pyrolysis section Z3, gasification section Z4 and discharging section Z5, with lengths of 200 mm, 500 mm, 1500 mm, 1000 mm and 100 mm respectively, wherein the dehydration section Z2, the pyrolysis section Z3 and the gasification section Z4 are three high-temperature reaction sections; the spiral pipe 1 is separated by a sealing area ZR arranged between each section, with a length of 100 mm; the upper part of the feeding section Z1 is provided with a feeding port 11, and the lower part of the discharging section Z5 is connected with a discharging device 12, and the inorganic waste residue outlet of the discharging device 12 is connected with a solid collecting system; the water vapor guiding unit 4, the pyrolysis gas guiding unit 5 and the gasification gas guiding unit 6 are all composed of hollow boxes, with a height of 200 mm; the dehydration section Z2, the pyrolysis section Z3 and the gasification section Z4 are separated by a first gas-permeable partition plate 41, a second gas-permeable partition plate 51 and a third gas-permeable partition plate 61 respectively; the dehydration section Z2, the pyrolysis section Z3 and the gasification section Z4 are evenly provided with 3 sets, 4 sets and 5 sets of microwave generators 9 respectively on both sides of the middle part; one end of the rotating shaft 2 extends out of the feeding section Z1 of the spiral pipe 1 and is connected with an externally arranged driver 3; the part of the rotating shaft 2 in the gasification section Z4 and the discharging section Z5 is a hollow shaft, which is internally provided with a gasification agent passage 21, and the part of the rotating shaft 2 in the remaining sections of the spiral pipe 1 is a solid shaft; the rotating shaft 2 is provided with a plurality of gas outlets 211 on the inner surface of the gasification section Z4 of the spiral pipe 1, which are in communication with the gasification agent passage 21 in the shaft and used for uniform release of the gasification agent to the gasification section Z4; the rotating shaft 2 is covered with spiral blades 22, which are arranged with a pitch of 100 mm, and the width of the sealing area ZR is set to 120 mm; the sealing area ZR is provided with sealing pieces 221 on the edges of the spiral blades 22 in the sealing area ZR of the spiral pipe 1, which tightly abut against the inner wall of the spiral pipe 1 to form a sealing structure; the inside of the spiral pipe 1 is filled with heat generating balls 7 made of wear-resistant silicon carbide wave-absorbing material (with an optimal microwave absorption frequency of 15 GHz) with a diameter of 10 mm; one side of the return pipe 8 is connected with the outlet of the discharging device 12 for discharging the heat generating balls 7, and the other side is connected with the feeding section Z1; the water vapor outlet of the water vapor guiding unit 4 is connected with the gasification agent passage 21 via a water vapor conveying pipe, and the gasification agent passage 21 can also be connected with an additional oxygen conveying pipe; the pyrolysis gas outlet at the upper part of the pyrolysis gas guiding unit 5 is connected with a liquid collecting system via a separation and condensation system; and the gas outlet at the upper part of the gasification gas guiding unit 6 is connected with a gas collecting system.

[0062] The waste rubber raw material with an average particle size of 10 mm is continuously fed into the internal heat type thermal conversion device through the feeding port, is fully mixed with the heating ball under the agitation and pushing of the spiral blade, the microwave generator emits microwaves with a frequency of 15 GHz into the spiral pipe in different reaction sections, the heating ball absorbs microwave energy to maintain a predetermined temperature by controlling the microwave power, and the raw material is heated to rapidly increase the temperature, the raw material continuously passes through different reaction sections separated by sealing zones, and the dehydration, pyrolysis and gasification processes occur at 200 DEG C, 550 DEG C and 1000 DEG C in turn; the generated gasification gas generates electricity in the fuel cell to provide electric energy for the device, effectively realizing the operation self-sustaining; the generated pyrolysis gas is separated and condensed to collect high-value liquid phase products, the liquid phase yield is 45.4wt%, and the target product olefin accounts for 46.7wt% in the liquid phase products, realizing the harmless disposal and high-value utilization of waste rubber.

[0063] Example 2

[0064] The same internal heat type thermal conversion device as in Example 1 is used in this example.

[0065] The corn cob raw material with an average particle size of 10 mm is continuously fed into the internal heat type thermal conversion device through the feeding port, is fully mixed with the heating ball under the agitation and pushing of the spiral blade, the microwave generator emits microwaves with a frequency of 15 GHz into the spiral pipe in different reaction sections, the heating ball absorbs microwave energy to maintain a predetermined temperature by controlling the microwave power, and the raw material is heated to rapidly increase the temperature, the raw material continuously passes through different reaction sections separated by sealing zones, and the dehydration, pyrolysis and gasification processes occur at 200 DEG C, 550 DEG C and 1000 DEG C in turn; the generated gasification gas generates electricity in the fuel cell to provide electric energy for the device, effectively realizing the operation self-sustaining, and the generated pyrolysis gas is separated and condensed to collect high-value liquid phase products; the yield of the target product furfural is 8.1wt%, realizing the high-value utilization of the corn cob raw material.

[0066] Example 3

[0067] The same internal heat type thermal conversion device as in Example 1 is used in this example.

[0068] The average particle size of 8mm of household garbage raw materials is continuously sent into the inner heat type thermal conversion device through the feeding port, is agitated and pushed by the spiral blade, and is fully mixed with the heating ball; the microwave generator emits microwaves with a frequency of 15GHz into the spiral pipe in different reaction sections, the heating ball absorbs microwave energy by controlling the microwave power to maintain a predetermined temperature, and the raw materials are heated to rapidly heat up; the raw materials continuously pass through different reaction sections separated by sealing areas, and undergo dehydration, pyrolysis and gasification processes at 250℃, 500℃ and 900℃, respectively; the generated gasification gas generates electricity in the fuel cell to provide electric energy for the device, effectively realizing operation self-sustaining; the whole device suppresses the emission of harmful substances such as dioxin, the weight loss rate reaches 81.3wt%, and the harmless treatment of household garbage is realized.

[0069] Example 4

[0070] This example uses the same inner heat type thermal conversion device as example 1.

[0071] The average particle size of 8mm of waste wood chip raw materials is continuously sent into the inner heat type thermal conversion device through the feeding port, is agitated and pushed by the spiral blade, and is fully mixed with the heating ball; the microwave generator emits microwaves with a frequency of 2.5GHz and 15GHz into the spiral pipe in different reaction sections, the raw materials directly absorb microwave energy by controlling the microwave power to rapidly heat up, and the temperature is maintained by the heating ball; the raw materials continuously pass through different reaction sections separated by sealing areas, and undergo dehydration, pyrolysis and gasification processes at 250℃, 550℃ and 900℃, respectively; the generated gasification gas generates electricity in the fuel cell to provide electric energy for the device, effectively realizing operation self-sustaining; the generated pyrolysis gas is separated and condensed to collect high-value liquid phase products, the liquid phase yield is 49.6wt%, and the high-value phenolic product accounts for 34.3wt% of the liquid phase products, realizing the high-value utilization of waste wood chips.

[0072] For the above embodiments of the present application, the specific structures and characteristics known in the scheme are not described in detail; each embodiment is described in a progressive manner, and the technical features involved in each embodiment can be combined with each other without conflict between them, and the same or similar parts between each embodiment can be referred to each other.

[0073] In the description of the present application, the terms "upper", "lower", "inner", and the like indicate the orientation or positional relationship shown in the drawings, which are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and should not be understood as a limitation on the present application; unless otherwise explicitly specified and limited, the terms "connected", "connected" should be broadly understood, for example, can be fixedly connected, can also be detachably connected, or integrally connected; can be directly connected, can also be indirectly connected through an intermediate medium, can be the internal communication of two elements. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances; in addition, the terms "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0074] The above is the preferred embodiment of the present application, it should be pointed out that, for those of ordinary skill in the art, without departing from the principles of the present application, a number of improvements and refinements can also be made, which should be considered to fall within the scope of the present application.

Claims

1. An internal heat thermal conversion device comprising a screw feeding system and a microwave generating system, said screw feeding system comprising a screw tube (1), a rotating shaft (2), screw blades (22) and a driver (3), characterized in that: The spiral pipe (1) is a hollow pipe arranged obliquely, filled with heat-generating balls (7), and sequentially provided with a feeding section (Z1), a dewatering section (Z2), a pyrolysis section (Z3), a gasification section (Z4) and a discharging section (Z5) from a lower end to a higher end, and separated by sealing zones (ZR) between adjacent sections; and a rotating shaft (2) is coaxially arranged in the spiral pipe (1); a feeding port (11) for feeding raw materials is arranged at the top of the feeding section (Z1), and a discharging device (12) is arranged at the bottom of the discharging section (Z5); the discharging device (12) is connected to the feeding section (Z1) through a return pipe (8), and the heat-generating balls (7) separated from inorganic waste residues are returned to the feeding section (Z1) through the return pipe (8); a water vapor guiding unit (4) is connected to an upper opening of the dewatering section (Z2) for discharging water vapor, a pyrolysis gas guiding unit (5) is connected to an upper opening of the pyrolysis section (Z3) for discharging pyrolysis gas, and a gasification gas guiding unit (6) is connected to an upper opening of the gasification section (Z4) for discharging gasification gas; the rotating shaft (2) penetrates through the feeding section (Z1) to the discharging section (Z5), spiral blades (22) are continuously and fixedly arranged around the rotating shaft (2), and a driver (3) is connected to and drives the rotating shaft (2) to rotate; a sealing sheet (221) is mounted on the edge of the spiral blade (22) in the sealing zone (ZR), and the sealing sheet (221) is attached to the inner wall of the spiral pipe (1) to form a seal; the rotating shaft (2) is a hollow shaft in the gasification section (Z4) and the discharging section (Z5), and a gasification agent channel (21) is arranged in the hollow shaft; the gasification agent channel (21) is connected to an exhaust port of the water vapor guiding unit (4), a plurality of gas outlet holes (211) are arranged on the inner surface of the gasification section (Z4) and connected to the gasification agent channel (21) for releasing gasification agent; a microwave generating system includes a plurality of microwave generators (9); the dewatering section (Z2), the pyrolysis section (Z3) and the gasification section (Z4) are each arranged with a plurality of microwave generators (9) on both sides of the middle part for emitting microwaves into the spiral pipe (1).

2. The internally heated thermal conversion apparatus of claim 1, wherein, The heat-generating balls (7) are composed of wave-absorbing materials that absorb specific frequency microwaves emitted by the microwave generators (9).

3. The internally heated thermal conversion apparatus of claim 2, wherein, A wear-resistant layer is arranged on the surface of the heat-generating balls (7).

4. The internally heated thermal conversion apparatus of claim 1, wherein, The width of the sealing zone (ZR) is not less than the pitch of one spiral blade (22).

5. The internally heated thermal conversion apparatus according to any one of claims 1 to 4, characterized in that, The water vapor guiding unit (4), the pyrolysis gas guiding unit (5) and the gasification gas guiding unit (6) each include a hollow box, the dewatering section (Z2) is connected to the box cavity of the water vapor guiding unit (4) through a first air-permeable partition (41), the pyrolysis section (Z3) is connected to the box cavity of the pyrolysis gas guiding unit (5) through a second air-permeable partition (51), and the gasification section (Z4) is connected to the box cavity of the gasification gas guiding unit (6) through a third air-permeable partition (61).

6. A thermal conversion method using the internal heating type thermal conversion apparatus according to any one of claims 1 to 5, characterized by, The method comprises the following steps: Step 1. Start the driver to drive the helical blade to rotate and push the heat-generating balls in the screw pipe to move from the feeding section to the discharging section; start the microwave generator to emit microwaves with specific frequency and power into the dehydration zone, the pyrolysis zone and the gasification zone of the screw pipe respectively, heat the heat-generating balls by the microwaves, and maintain the set dehydration temperature, pyrolysis temperature and gasification temperature; Step 2. The raw material is sent into the feeding section through the feeding port, mixed with the heat-generating balls by the stirring and pushing of the helical blade, and enters the dehydration section; Step 3. The raw material is heated rapidly and dehydrated in the dehydration section, and the generated water vapor enters the water vapor guiding unit through the first gas-permeable partition under the action of pressure, and then enters the gasification agent channel; Step 4. After dehydration, the raw material enters the pyrolysis section to be pyrolyzed, and the generated pyrolysis gas enters the pyrolysis gas guiding unit through the second gas-permeable partition under the action of pressure, is separated and condensed, and then discharged and collected; the remaining residual carbon enters the gasification section; Step 5. In the gasification section, the gasification agent in the gasification agent channel is released through the gas outlet and mixed with the residual carbon to generate a gasification reaction, and the generated gasification gas enters the gasification gas guiding unit through the third gas-permeable partition under the action of pressure, and then is discharged and collected; Step 6. After gasification, the remaining inorganic waste residue is discharged and collected after the heat-generating balls are separated in the discharging device; the separated heat-generating balls are cooled through the return pipe and then re-enter the feeding section of the screw pipe to continue the cycle.

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