Coking device based on phase change heat transfer

Abstract

The application discloses a coking device based on phase change heat transfer and belongs to the technical field of coke oven coking. The coking device comprises multiple heat pipe units, wherein the evaporator and the condenser are connected through a heat pipe pipeline to form a closed circulation loop; the heating unit comprises a second shell, the inside of the second shell is filled with microwave absorbing material, and multiple microwave emission plates for heating the microwave absorbing material are arranged on the second shell, and the evaporator in the heat pipe unit is installed in the inside of the second shell; and the coking unit comprises multiple carbonization chambers which are spaced apart, the carbonization chambers are located above the heating unit, and the first phase change heat storage material is arranged in the gap between adjacent carbonization chambers, and the condenser in the heat pipe unit is installed in the inside of the first phase change heat storage material. According to the scheme, the heat transfer path between microwave heating and the carbonization chamber is designed, so that the microwave heating is applied to industrial coke oven coking, the heat starting time is reduced, the energy utilization efficiency is improved, and the heating uniformity is improved.

Description

Technical Field

[0001] This invention relates to the field of coking technology, and more specifically, to a coking apparatus based on phase change heat transfer. Background Technology

[0002] The main heating method for existing industrial-grade coke ovens is as follows: coal gas is burned in the combustion chamber to produce high-temperature gas, which is then used to heat the coke oven through a complex gas distribution and reversing system. This method of direct coal gas heating has several drawbacks. First, it results in relatively low energy utilization. Second, it requires a significant amount of time for cold start-up and heating of the carbonization chamber, meaning the heat storage period for the carbonization chamber is relatively long, leading to low coke oven production efficiency. Furthermore, this heating method results in poor heating uniformity in the carbonization chamber and insufficient temperature control precision, leading to significant fluctuations in the quality of the produced coke and limiting its subsequent applications in industries such as steel smelting.

[0003] Shortening the start-up time of coke ovens and further improving the uniformity of heating have always been important research topics in the metallurgical field. One direction is to directly heat coal cakes using microwaves. For example, Chinese patent application No. 2023112917415 discloses a device and method for producing coke from kilogram-level coking coal using microwave heating. Specifically, it includes a microwave heating furnace, a support device installed inside the microwave heating furnace, and a container placed on the support device. The container is used to hold kilogram-level single-type coking coal. A cathode block and an anode block are installed inside the microwave heating furnace, and a 2000V~2200V DC high-voltage current is supplied between the cathode block and the anode block. A microwave transmitter is installed at the bottom of the microwave heating furnace. A microwave energy output device is installed near the anode block. The microwave energy output device acquires the electric field energy between the cathode block and the anode block and converts the electric field energy into microwave energy, which is then transmitted to the microwave transmitter. The microwave transmitter performs microwave heating inside the microwave heating furnace. This application integrates microwave heating and high-temperature coking, using a DC electric field to continuously amplify microwave energy and heat coking coal in the form of microwaves to produce coke. However, this application is only suitable for heating coking coal at the kilogram level in the laboratory. The method of directly heating coal with microwaves cannot be adapted to industrial-scale coke oven production.

[0004] For example, Chinese patent application No. 2017105424193 discloses a 60kg microwave coking test furnace and its coking method. This application uses microwave to directly heat coking coal, which makes the coking coal heat up quickly and can shorten the coking time. At the same time, it heats the coking coal from the inside and outside simultaneously, resulting in coke products with good uniformity. The microwave heating efficiency is high, the required microwave power is low, and the coking coal heats up quickly. However, microwave heating of coal is still in the experimental coking furnace stage and cannot be adapted to industrial-grade coking furnace production.

[0005] As can be seen from the above, the existing microwave heating method for coal cannot be directly adapted to industrial coking. Summary of the Invention

[0006] To address the technical problem that existing microwave heating methods cannot be directly applied to industrial coking, this invention provides a coking device based on phase change heat transfer. This solution optimizes the heat transfer path between microwave heating and the carbonization chamber, thereby facilitating the application of microwave heating in industrial coking. It reduces the hot start-up time and offers high microwave heating efficiency, thus improving both energy utilization efficiency and the uniformity of coal heating.

[0007] To achieve the above objectives, the technical solution provided by this invention is as follows:

[0008] This invention provides a coking device based on phase change heat transfer, comprising: multiple heat pipe units, each including an evaporator and a condenser, wherein the evaporator and condenser are connected by heat pipes to form a closed loop, and a heat transfer medium circulates within the closed loop; a heating unit, including a second shell, the interior of which is filled with microwave absorbing material and has multiple microwave emitting plates for heating the microwave absorbing material, wherein the evaporators in the heat pipe units are all installed inside the second shell, and heat is provided to the evaporators through the microwave absorbing material; and a coking unit, comprising multiple spaced carbonization chambers, the carbonization chambers being located above the heating unit, and a first phase change heat storage material being provided in the gaps between adjacent carbonization chambers, wherein the condensers in the heat pipe units are all installed inside the first phase change heat storage material, and heat is provided to the first phase change heat storage material through the condensers.

[0009] Furthermore, the heat pipe is equipped with a backflow preventer valve located in the heat pipe between the outlet end of the evaporator and the inlet end of the condenser. The backflow preventer valve is used to restrict the heat transfer medium from flowing back from the inlet end of the condenser to the outlet end of the evaporator.

[0010] Furthermore, the reverse valve adopts a Tesla valve structure, which includes a main channel and multiple reverse valve branches connected to the main channel. The multiple reverse valve branches are located on one or both sides of the main channel.

[0011] Furthermore, the backflow preventer valve is equipped with a flow-limiting component inside the end near the evaporator. The flow-limiting component includes a flow-limiting branch connected to the main channel. The flow-limiting branch and the backflow preventer branch located on the other side of the main channel are centrally symmetrical and are staggered along the axis of the main channel.

[0012] Furthermore, the main channel is equipped with an adjustment baffle, which is used to control the opening of the main channel.

[0013] Furthermore, one end of the rotating shaft in the adjusting baffle extends outside the heat pipe, and the adjusting transmission component and adjusting drive component are located outside the heat pipe. The adjusting drive component drives the adjusting baffle to rotate through the adjusting transmission component, thereby controlling the opening of the main channel.

[0014] Furthermore, the adjustment drive component uses a motor, and the adjustment transmission component uses a gear set.

[0015] Furthermore, multiple microwave emitting plates and multiple evaporators are staggered and distributed inside the second shell; the heat transfer medium includes alkali metal medium and nanoparticles; the heat pipe pipeline has a capillary microgroove structure inside.

[0016] Furthermore, the heat pipe unit is equipped with a working fluid regulating valve connected to the heat pipe pipeline, which is used to evacuate the heat pipe pipeline or control the amount of heat transfer working fluid in the heat pipe unit.

[0017] Furthermore, the interior of the second shell is filled with a second phase change thermal storage material; the interior of the carbonization chamber is equipped with multiple temperature sensors spaced apart along the height direction.

[0018] Compared with the prior art, the technical solution provided by this invention has the following advantages:

[0019] (1) This invention optimizes the heat transfer path between microwave heating and the carbonization chamber. Specifically, it uses a combination of a microwave emitting plate, microwave absorbing material, and heat pipe unit to heat the carbonization chamber. Compared with existing gas-fired heating, microwave heating requires less time and has higher heat conversion efficiency. Furthermore, compared with direct heating of the first phase change heat storage material by the microwave emitting plate, the addition of a heat pipe unit enables rapid heat transfer without requiring continuous phase change heat storage material between the sidewalls of adjacent carbonization chambers and the microwave absorbing material. In addition, the evaporator and condenser in this heat pipe unit are connected by heat pipes, meaning the heat pipe unit is a split-type heat pipe structure, allowing for more flexible arrangement of the evaporator and condenser.

[0020] (2) The present invention further optimizes the internal structure of the heat pipe unit. Specifically, a backflow preventer valve is provided inside the heat pipe to restrict the heat transfer medium from flowing back from the inlet end of the condenser to the outlet end of the evaporator, that is, to prevent the gaseous heat transfer medium from flowing back from the condenser to the evaporator, and also to prevent heat from being transferred in reverse from the first phase change heat storage material to the microwave absorbing material. Furthermore, the coking temperature in the coke oven is relatively high. In order to maintain the long-term stable operation of the backflow preventer valve in the high-temperature environment, the backflow preventer valve is preferably a Tesla valve structure.

[0021] (3) The present invention further adds a flow-limiting component to the heat pipe unit. Specifically, the flow-limiting branch and the reverse-blocking branch on the other side of the main channel are centrally symmetrical. The flow directions of the flow-limiting branch and the reverse-blocking branch are opposite at the intersection, resulting in a collision, thereby reducing the flow velocity inside the main channel. Furthermore, an adjusting baffle is added. The opening of the main channel is controlled by adjusting the rotation of the baffle, thereby achieving a better flow-limiting effect. Attached Figure Description

[0022] Figure 1 This is a three-dimensional structural diagram of the external structure of a coking device based on phase change heat transfer according to an embodiment of the present invention.

[0023] Figure 2 This is a schematic diagram of a partial three-dimensional structure inside a coking device based on phase change heat transfer according to an embodiment of the present invention.

[0024] Figure 3 This is a schematic diagram of the internal structure of the heating unit in a coking device based on phase change heat transfer according to an embodiment of the present invention.

[0025] Figure 4 This is a schematic diagram of the principle structure of the heat pipe unit in the coking device based on phase change heat transfer according to an embodiment of the present invention.

[0026] Figure 5 This is a partial structural diagram of the reversing valve in a coking unit based on phase change heat transfer according to an embodiment of the present invention.

[0027] Figure 6 This is a partial three-dimensional structural diagram of the flow-limiting component in a coking device based on phase change heat transfer according to an embodiment of the present invention.

[0028] Figure 7 This is a three-dimensional structural diagram of the external structure of the heat dissipation unit in a coking device based on phase change heat transfer according to an embodiment of the present invention.

[0029] Figure 8 This is a schematic diagram of a partial three-dimensional structure inside the heat dissipation unit of a coking device based on phase change heat transfer, according to an embodiment of the present invention. Figure 1 .

[0030] Figure 9 This is a schematic diagram of a partial three-dimensional structure inside the heat dissipation unit of a coking device based on phase change heat transfer, according to an embodiment of the present invention. Figure 2 .

[0031] Figure 10 This is a schematic diagram of the internal structure of the heat pipe in a coking unit based on phase change heat transfer, according to an embodiment of the present invention.

[0032] Label Explanation:

[0033] 1. Coking Unit; 101. Furnace Wall; 102. Carbonization Chamber; 103. Feed Inlet; 104. Discharge Outlet; 105. First Phase Change Thermal Storage Material; 106. First Insulation Layer; 107. Temperature Sensor; 2. Heat Pipe Unit; 201. Heat Pipe Pipeline; 202. Reverse Resistance Valve; 221. Main Channel; 222. Reverse Resistance Bend; 223. Reverse Resistance Wing-Shaped Barrier; 203. Flow Limiting Component; 231. Adjusting Baffle; 232. Adjusting Transmission Component; 233. Adjusting Drive Components; 234. Flow-limiting wing-shaped obstruction; 235. Flow-limiting bend; 204. Evaporator; 205. Condenser; 206. Working fluid regulating valve; 207. Heat transfer working fluid; 3. Heating unit; 301. Second phase change thermal storage material; 302. Microwave absorbing material; 303. Microwave emitting plate; 304. Second housing; 305. Heat dissipation unit; 351. Heat dissipation fins; 352. Heat dissipation fan; 353. Heat dissipation housing; 354. Gravity heat pipe; 4. Control unit. Detailed Implementation

[0034] To further understand the content of this invention, a detailed description of the invention will be provided in conjunction with the accompanying drawings and embodiments.

[0035] The structures, proportions, and sizes illustrated in the accompanying drawings are merely for illustrative purposes and to aid those skilled in the art in understanding and reading the invention. They are not intended to limit the scope of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of the invention, should still fall within the scope of the technical content disclosed herein. Furthermore, terms such as "upper," "lower," "left," "right," and "middle" used in this specification are merely for clarity and not intended to limit the scope of implementation. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention's implementation.

[0036] It should be noted that the evaporator 204 and condenser 205 in heat pipe unit 2 are explained as follows: Under normal conditions, the heat transfer medium 207 absorbs heat in the evaporator 204, changing from a liquid to a gaseous state. In the condenser 205, the heat transfer medium 207 liquefies, releasing heat. In this state, in the circulation loop of heat pipe unit 2, the inlet end of the liquid heat transfer medium in the evaporator 204 is called the inlet end of the evaporator 204, and the outlet end of the gaseous heat transfer medium in the evaporator 204 is called the outlet end of the evaporator 204. The outlet end of the evaporator 204 is connected to the inlet end of the condenser 205 via heat pipe 201. The connection between the inlet end of the evaporator 204 and the outlet end of the condenser 205 via heat pipe 201 forms a closed circulation loop for the flow of heat transfer medium 207. (Refer to...) Figure 4As shown, the heat transfer medium 207 flows clockwise in the circulation loop. Under certain operating conditions, unlike the normal state, especially when the heating unit 3 stops heating, the temperature of the evaporator 204 in the circulation loop may be lower than the temperature of the condenser 205. At this time, the condenser 205 may transfer heat to the evaporator 204 in the reverse direction, that is, the heat transfer medium 207 flows in the reverse direction in the closed circulation loop. However, this flow state accounts for a small proportion. At this time, the pipes of the heat pipe unit 2 located inside the second shell 304 are still called the evaporator 204, and the pipes of the heat pipe unit 2 located inside the first phase change heat storage material 105 are still called the condenser 205. The ports referred to by the inlet and outlet ends of the evaporator 204 and the condenser 205 are the same as those referred to in the normal state.

[0037] This embodiment provides a coking apparatus based on phase change heat transfer, referencing... Figures 1-4 As shown, the system includes multiple heat pipe units 2, each including an evaporator 204 and a condenser 205. The evaporator 204 and condenser 205 are connected by heat pipes 201 to form a closed loop, in which a heat transfer medium 207 circulates. A heating unit 3 includes a second housing 304, the interior of which is filled with microwave absorbing material 302. The interior of the second housing 304 is also equipped with multiple microwave emitting plates 303 for heating the microwave absorbing material 302. The evaporator 204 in each heat pipe unit 2... All four are installed inside the second housing 304, and provide heat to the evaporator 204 through the microwave absorbing material 302; the coking unit 1 includes multiple spaced carbonization chambers 102, which are located above the heating unit 3, and the gaps between adjacent carbonization chambers 102 are provided with first phase change heat storage material 105. The condensers 205 in the heat pipe unit 2 are all installed inside the first phase change heat storage material 105, and provide heat to the first phase change heat storage material 105 through the condensers 205; and the control unit 4 for controlling the operation of the coking unit.

[0038] The gap between adjacent carbonization chambers 102, i.e. the gap between the wall bricks in adjacent carbonization chambers 102, is filled with a first phase change heat storage material 105.

[0039] This invention employs a combination of a microwave emitting plate 303, a microwave absorbing material 302, and a heat pipe unit 2 to heat the carbonization chamber 102. Compared to existing gas-fired heating methods, microwave heating has a shorter heating time and higher heat conversion efficiency, and it also improves the uniformity of heating the carbonization chamber 102. Electrical energy is converted into microwaves by the microwave emitting plate 303, and the microwave absorbing material 302 absorbs the microwaves and converts them into heat energy. This heat energy heats the evaporator 204 in the heat pipe unit 2. The heat transfer medium 207 in the evaporator 204 absorbs heat and transforms into a gaseous state. It then flows from the outlet of the evaporator 204 to the inlet of the condenser 205 through the heat pipe 201. The gaseous heat transfer medium 207 liquefies inside the condenser 205, releasing heat. The carbonization chamber 102 is located above the heating unit 3. The liquefied heat transfer medium 207 inside the condenser 205 flows back to the inlet of the evaporator 204 from its outlet due to gravity. This heating method, which uses heat pipe unit 2 to transfer heat from microwave absorbing material 302 to first phase change thermal storage material 105, achieves rapid heat transfer compared to directly heating the phase change thermal storage material using microwave emitting plate 303. Furthermore, it eliminates the need for continuous phase change thermal storage material between the outer wall of adjacent carbonization chamber 102 and microwave absorbing material 302. Simultaneously, both ends of the evaporator 204 and condenser 205 in this heat pipe unit 2 are connected via heat pipe lines 201, meaning the heat pipe unit 2 is a split-type heat pipe structure, allowing for more flexible arrangement of the evaporator 204 and condenser 205.

[0040] It should be noted that although the microwave emitting plate 303 can directly heat coal or coal cakes, the effective heating power will decrease due to differences in the dielectric loss of coke, absorption and scattering by volatiles, and convection losses of gases inside the furnace. Furthermore, the limited penetration of microwaves and the varying microwave absorption capabilities of materials within the coke oven limit the temperature uniformity of microwave heating, especially in industrial-grade coke ovens where the coal mass is relatively large. By efficiently converting energy from microwaves into Joule heat through the microwave absorbing material 302, the heat conversion efficiency is improved. Additionally, combined with the heat pipe unit 2, the temperature of the first phase change heat storage material 105 can be precisely controlled, thus facilitating the application of microwave heating in industrial coke oven coking.

[0041] The carbonization chamber 102 has a coal inlet 103 at the top and a coke outlet 104 on the side. The coking unit 1 also includes a furnace wall 101, which surrounds the multiple carbonization chambers 102 and has through holes corresponding to the inlet 103 and outlet 104. The inner or outer wall of the furnace wall 101 has a first insulation layer 106. Preferably, the furnace wall 101 can be made of high-alumina brick or silica brick. More preferably, the inner wall of the carbonization chamber 102 is coated with an alumina-silica coating to improve its high-temperature resistance and corrosion resistance.

[0042] The evaporator 204 is preferably made of molybdenum-rhenium alloy. More preferably, it is coated with an HfC / YAG (hafnium carbide / yttrium aluminum garnet) coating to reduce microwave damage to the evaporator 204. Even more preferably, fins can be added to the exterior of the evaporator 204 to enhance the heat exchange effect.

[0043] The condenser 205 is preferably made of stainless steel or the like, and is coated with a ceramic-based coating on its exterior to increase its corrosion resistance and high-temperature resistance.

[0044] The microwave absorbing material 302 is preferably in particulate form and can be made of silicon carbide-based composite material or ferrite-alumina gradient material.

[0045] As an extension, the phase change material inside the first phase change thermal storage material 105 can be a molten salt or a composite phase change material, such as Al-Si alloy, Cu-Si, Cu-Mg and other Cu-based alloys.

[0046] For details, please refer to Figure 4 , Figure 5 As shown, the heat pipe unit 2 is also equipped with a backflow preventer valve 202. The backflow preventer valve 202 is located in the heat pipe 201 between the outlet end of the evaporator 204 and the inlet end of the condenser 205, and is used to restrict the backflow of the heat transfer medium 207 from the inlet end of the condenser 205 to the outlet end of the evaporator 204. The coking chamber 102 of the coke oven is generally heated intermittently. When the microwave emitting plate 303 stops heating the microwave absorbing material 302, the temperature of the evaporator 204 drops relatively quickly. However, because the condenser 205 is embedded in the first phase change heat storage material 105, the temperature of the condenser 205 will be higher than that of the evaporator 204. At this time, the pressure inside the condenser 205 is too high, which may cause the gaseous heat transfer medium 207 to flow in reverse, especially when the evaporator 204 starts to heat from room temperature. To prevent the gaseous heat transfer medium 207 from flowing back from the condenser 205 to the evaporator 204, that is, to prevent heat from being transferred in reverse from the first phase change heat storage material 105 to the microwave absorbing material 302, a backflow preventer valve 202 is provided between the condenser 205 and the evaporator 204.

[0047] The temperature of coking in a coke oven is usually above 1000℃, so the working environment of the heat pipe unit 2 is relatively harsh. In order to maintain the long-term stable operation of the reverse valve 202 in the high-temperature environment, the reverse valve 202 preferably adopts a Tesla valve structure, which includes a main channel 221 and multiple reverse branches connected to the main channel 221. The multiple reverse branches are set on one or both sides of the main channel 221.

[0048] To further reduce heat loss, the corresponding pipe sections of the heat pipe 201 located outside the heating unit 3 and the coking unit 1 are provided with an insulation layer wrapped around them.

[0049] Furthermore, the reverse valve 202 is also provided with a flow limiting component 203 inside the end near the evaporator 204. The flow limiting component 203 includes a flow limiting branch connected to the main channel 221. The flow limiting branch and the reverse valve branch located on the other side of the main channel 221 are centrally symmetrical and are staggered along the axis of the main channel 221.

[0050] In this design, by placing the flow-limiting component 203 at one end of the backstop valve 202 near the evaporator 204, which is the end of the flow of the heat transfer medium 207 in the backstop valve 202 along the flow-limiting direction, when the flow reaches this end of the backstop valve 202, the amount of heat transfer medium 207 is relatively small. That is, the amount of heat transfer medium flowing back from the condenser 205 to the interior of the evaporator 204 gradually decreases along the flow-limiting direction of the backstop valve 202. Therefore, placing the flow-limiting component 203 at this end has little impact on the unidirectional flow-limiting effect of the backstop valve 202. Thus, it is preferable to place the flow-limiting component 203 at this end of the evaporator 204.

[0051] refer to Figure 5 As shown, the blocking branch includes a blocking wing-shaped barrier 223 and a blocking bend 222. The blocking wing-shaped barrier 223 is located inside the blocking bend 222, forming a blocking branch. The openings on both sides of the blocking bend 222 are connected to the main channel 221. The main channel 221 and the blocking branch are existing technologies in the field and will not be described in detail here.

[0052] As an extension option, refer to Figure 4 , Figure 5 As shown, the flow-limiting branch includes a flow-limiting wing-shaped barrier 234 and a flow-limiting bend 235. The flow-limiting wing-shaped barrier 234 is located inside the flow-limiting bend 235 to form the flow-limiting branch. The flow-limiting branch and the reverse-blocking branch located on the other side of the main channel 221 form a centrally symmetrical figure, that is, the flow-limiting branch and the reverse-blocking branch have the same structure and are relative to each other. The flow-limiting branch reduces the flow velocity of the heat transfer medium 207 from the evaporator 204 to the condenser 205.

[0053] It should be noted that the structure and relative position of the flow-limiting branch and the reverse-blocking branch can also adopt other designs. The gaseous heat transfer medium 207 flows into the flow-limiting branch from the main channel 221. The direction of the heat transfer medium 207 flowing into the flow-limiting branch is at an acute angle to the flow direction of the heat transfer medium in the main channel 221. The direction of the heat transfer medium 207 flowing out of the flow-limiting branch is at an obtuse angle to the flow direction of the heat transfer medium 207 in the main channel 221. That is, the direction of the heat transfer medium flowing out of the flow-limiting branch is opposite to the flow direction of the heat transfer medium in the main channel 221. Collision occurs at the junction, thereby reducing the flow velocity inside the main channel 221.

[0054] As an extension option, refer to Figure 4 , Figure 6As shown, the main channel 221 is also equipped with an adjusting baffle 231, which is used to control the opening of the main channel 221.

[0055] As a further extension, one end of the rotating shaft in the adjusting baffle 231 extends to the outside of the heat pipe 201. The adjusting transmission component 232 and the adjusting drive component 233 are located outside the heat pipe 201. The adjusting drive component 233 drives the adjusting baffle 231 to rotate through the adjusting transmission component 232, thereby controlling the opening of the main channel 221.

[0056] It should be noted that by setting up flow-limiting branches, the flow directions of the flow-limiting branches and the reverse-blocking branches are opposite at the intersection, resulting in a collision and thus reducing the internal flow velocity, which limits the flow-limiting effect. Furthermore, an adjusting baffle 231 is added. By adjusting the rotation of the baffle 231, the opening of the main channel 221 can be controlled to achieve a better flow-limiting effect.

[0057] The flow limiting component 203 is installed on the corresponding pipeline of the heat pipe 201 located outside the heating unit 3 and the coking unit 1, thereby facilitating the operation of the adjustment drive component 233 and reducing the limitations on the selection of the adjustment drive component 233.

[0058] To achieve automatic adjustment of the rotation angle of the adjusting baffle 231, preferably, the adjusting drive 233 is a motor, and the adjusting transmission 232 is a gear set. The control unit 4 controls the rotation of the adjusting drive 233, which in turn drives the central shaft of the adjusting baffle 231 to rotate via the adjusting transmission 232.

[0059] As a further preferred embodiment, multiple microwave emitting plates 303 and multiple evaporators 204 are staggered and distributed in the microwave absorbing material 302, which helps to improve the uniformity of the internal temperature of the heating unit 3. At the same time, the evaporators 204 and the microwave emitting plates 303 do not directly contact each other; the energy conversion and transfer between them only occurs through the microwave absorbing material 302, thereby reducing the limitations on the selection of the heat pipe wall material and the heat transfer medium 207 in the heat pipe unit 2.

[0060] To improve the heat transfer performance of heat pipe unit 2, the heat transfer medium 207 includes an alkali metal working medium and nanoparticles. The alkali metal working medium can be selected from sodium, potassium, or molten salt, etc., and the nanoparticles can be selected from alumina, graphene, etc.

[0061] To improve the flow efficiency of the heat transfer medium 207 in the heat pipe 201, refer to Figure 10 As shown, the interior of the heat pipe 201 has a capillary-like groove structure. Specifically, the inner wall of the heat pipe 201 is formed by etching to create the capillary-like grooves.

[0062] In some specific embodiments, the heat pipe unit 2 further includes a working fluid regulating valve 206, which is connected to the heat pipe line 201 and is used to evacuate the heat pipe line 201 or control the amount of heat transfer working fluid in the heat pipe unit 2. Preferably, the working fluid regulating valve 206 is located near the outlet end of the evaporator 204.

[0063] In order to make full use of the thermal energy of the microwave absorbing material, the interior of the shell wall of the second shell 304 is filled with a second phase change thermal storage material 301; the excess heat that is not absorbed by the evaporator 204 is stored through the second phase change thermal storage material 301.

[0064] Preferably, the carbonization chamber 102 is provided with a plurality of single-row temperature sensors 107 spaced apart along the height direction. The temperature sensors 107 feed back the detected temperature to the control unit 4. The control unit 4 adjusts the output power of the microwave emitting plate 303 and the specific intermittent working mode accordingly to maintain a relatively stable internal temperature of the carbonization chamber 102.

[0065] As a preferred embodiment of the microwave emitting plate 303, refer to Figures 7-9 As shown, the microwave emitting plate 303 also has a heat dissipation unit 305 inside, which is used to transfer the heat inside the microwave emitting plate 303 to the outside of the second housing 304.

[0066] Specifically, the heat dissipation unit 305 includes multiple gravity heat pipes 354; the upper ends of each gravity heat pipe 354 are respectively disposed inside the multiple microwave emitting plates 303, and the lower ends extend to the outside of the second housing 304. More specifically, the lower ends of the gravity heat pipes 354 are disposed inside the heat dissipation housing 353, and the cooling fan 352 is disposed inside the heat dissipation housing 353 to dissipate the heat inside the heat dissipation housing 353 to the outside, that is, to provide air cooling for the lower ends of the gravity heat pipes 354, thereby reducing the temperature of the microwave emitting plates 303 and improving their service life. Further preferably, the lower end of each gravity heat pipe 354 is provided with multiple heat dissipation fins 351 to improve its heat dissipation efficiency.

[0067] As another way to reduce the operating temperature of the microwave emitting plate 303, a heat insulation plate made of thermal insulation material is covered on the outside of the microwave emitting plate 303. This thermal insulation material can be made of BN (boron nitride) composite material to reduce the adverse effects of the temperature rise of the microwave absorbing material 302 on the microwave emitting plate 303.

[0068] The present invention and its embodiments have been described above illustratively. This description is not restrictive, and the figures shown are only one embodiment of the present invention; the actual structure is not limited thereto. Therefore, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the spirit of the present invention, such designs should fall within the protection scope of the present invention.

Claims

1. A coking apparatus based on phase change heat transfer, characterized in that, include: Multiple heat pipe units (2), each of the multiple heat pipe units (2) includes an evaporator (204) and a condenser (205), wherein the evaporator (204) and the condenser (205) are connected by a heat pipe (201) to form a closed loop, and a heat transfer medium (207) circulates in the closed loop. The heating unit (3) includes a second housing (304), which is filled with microwave absorbing material (302) and has multiple microwave emitting plates (303) for heating the microwave absorbing material (302). The evaporators (204) in the heat pipe unit (2) are all installed inside the second housing (304), and heat is supplied to the evaporators (204) through the microwave absorbing material (302). And a coking unit (1), the coking unit (1) includes a plurality of carbonization chambers (102) spaced apart, the carbonization chambers (102) are located above the heating unit (3), and a first phase change heat storage material (105) is provided in the gap between adjacent carbonization chambers (102). The condensers (205) in the heat pipe unit (2) are all installed inside the first phase change heat storage material (105), and provide heat to the first phase change heat storage material (105) through the condensers (205); The heat pipe (201) is also equipped with a backflow preventer valve (202). The backflow preventer valve (202) is located in the heat pipe (201) between the outlet end of the evaporator (204) and the inlet end of the condenser (205). It is used to restrict the heat transfer medium (207) from flowing back from the inlet end of the condenser (205) to the outlet end of the evaporator (204). The backflow preventer valve (202) adopts a Tesla valve structure, which includes a main channel (221) and multiple backflow preventer branches connected to the main channel (221). The multiple backflow preventer branches are set on one or both sides of the main channel (221).

2. The coking apparatus based on phase change heat transfer according to claim 1, characterized in that, The reverse valve (202) is further provided with a flow limiting component (203) inside the end near the evaporator (204). The flow limiting component (203) includes a flow limiting branch connected to the main channel (221). The flow limiting branch and the reverse valve branch located on the other side of the main channel (221) are centrally symmetrical and are staggered along the axis of the main channel (221). The main channel (221) is further provided with an adjusting baffle (231) inside. The adjusting baffle (231) is used to control the opening degree of the main channel (221).

3. The coking apparatus based on phase change heat transfer according to claim 2, characterized in that, One end of the rotating shaft in the adjusting baffle (231) extends to the outside of the heat pipe (201). The adjusting transmission component (232) and the adjusting drive component (233) are located outside the heat pipe (201). The adjusting drive component (233) drives the adjusting baffle (231) to rotate through the adjusting transmission component (232), thereby controlling the opening of the main channel (221).

4. The coking apparatus based on phase change heat transfer according to claim 3, characterized in that, The adjustment drive component (233) is a motor, and the adjustment transmission component (232) is a gear set.

5. The coking apparatus based on phase change heat transfer according to claim 1 or 2, characterized in that, Multiple microwave emitting plates (303) and multiple evaporators (204) are staggered and distributed inside the second shell (304); the heat transfer medium (207) includes alkali metal medium and nanoparticles; the interior of the heat pipe (201) has a capillary microgroove structure.

6. The coking apparatus based on phase change heat transfer according to claim 1 or 2, characterized in that, The heat pipe unit (2) is equipped with a working fluid regulating valve (206) connected to the heat pipe pipeline (201), which is used to evacuate the heat pipe pipeline (201) or control the amount of heat transfer working fluid (207) in the heat pipe unit (2).

7. The coking apparatus based on phase change heat transfer according to claim 1 or 2, characterized in that, The interior of the shell wall of the second shell (304) is filled with a second phase change thermal storage material (301); the interior of the carbonization chamber (102) is provided with a plurality of temperature sensors (107) spaced apart along the height direction.

Images