CVD (chemical vapor deposition) silicon carbide heater processing system and process thereof

Abstract

The invention relates to the field of silicon carbide heater processing, in particular to a CVD (chemical vapor deposition) silicon carbide heater processing system and process, and adopts the technical scheme that the CVD silicon carbide heater processing system comprises a spray granulation module and a feeding and discharging heat exchange module; the spray granulation module comprises a drying tower, the upper end of the drying tower is connected with a slurry atomization device, and the bottom of the drying tower is provided with a particle discharge device; the feeding and discharging heat exchange module comprises a preheating cabin, a slurry pipe is installed on one side of the preheating cabin, an upper partition plate and a lower partition plate are installed on the inner walls of the upper side and the lower side of the preheating cabin correspondingly, and a heat exchange pipe is installed between the upper partition plate and the lower partition plate; the spray granulation device has the beneficial effects that slurry is guided into the preheating cabin through the slurry pipe and then guided into the drying tower for spray granulation, on the other hand, high-temperature particles in the drying tower are guided into the heat exchange pipe through the particle discharging device, the slurry in the preheating cabin is heated by the high-temperature particles through the heat exchange pipe, and meanwhile the high-temperature particles are cooled by the slurry; therefore, the effect of simultaneously preheating the slurry and cooling the particles is achieved.

Description

Technical Field

[0001] This invention relates to the field of silicon carbide heater processing, and more specifically to a CVD silicon carbide heater processing system and its process. Background Technology

[0002] A CVD (Chemical Vapor Deposition) silicon carbide heater processing system is an equipment system that uses CVD technology to produce silicon carbide (SiC) heating elements. Silicon carbide (SiC), as a high-temperature and high-efficiency material, has excellent thermal conductivity, high-temperature resistance, oxidation resistance and mechanical strength, and is widely used in the field of semiconductor vacuum coating. In the semiconductor vacuum coating process, the silicon carbide heater is mainly used to provide the required heat to promote the uniform deposition of materials on the surface of the substrate (such as silicon wafers, glass or other semiconductor materials) and form a thin film.

[0003] Existing silicon carbide heater processing systems involve multiple steps, including: batching, slurry preparation, spray granulation, dry pressing, pre-calcination, siliconization, crystallization, grinding, and testing. In the spray granulation process, the produced particles are usually at a high temperature. High temperatures can cause the particles to become viscous, and if they are not properly cooled, they are prone to sticking together during the molding process, leading to molding difficulties and potential issues such as material deformation or unstable quality, affecting the performance and quality of the final product. On the other hand, the slurry usually needs to be preheated before spray granulation to reduce its viscosity and make it easier to atomize through the nozzle.

[0004] However, in the existing processing system, the preheating of slurry and the cooling of particles require additional equipment and energy input, which leads to an increase in energy consumption in the overall production process, thereby increasing production costs. In addition, the additional preheating and cooling steps will prolong the overall production cycle, thus affecting production efficiency. The processing time of each batch may therefore become longer, resulting in a decrease in capacity utilization.

[0005] Therefore, it is necessary to invent a CVD silicon carbide heater processing system and its process. Summary of the Invention

[0006] To achieve the above objectives, the present invention provides the following technical solution: a CVD silicon carbide heater processing system and its process, including a spray granulation module and a feed and discharge heat exchange module;

[0007] The spray granulation module includes a drying tower, a hot air tower installed on the side of the drying tower, the upper end of the hot air tower being connected to the upper part of the drying tower, an electric heater installed inside the hot air tower, a blower installed at the bottom of the hot air tower, a slurry atomizing device connected to the upper end of the drying tower, the slurry atomizing device including an atomizing tube, one end of the atomizing tube being connected to the top of the drying tower, a particle discharge device installed at the bottom of the drying tower, the particle discharge device including a separation pipe, one end of the separation pipe being connected to the bottom of the drying tower, the other end being connected to a conveying pipe, the conveying pipe being connected to a U-shaped conduit;

[0008] The inlet and outlet heat exchange module includes a preheating chamber. A slurry pipe is installed on one side of the preheating chamber, and an atomizing pipe is connected to the other side. Upper and lower partitions are installed on the upper and lower inner walls of the preheating chamber, respectively. A heat exchange pipe is installed between the upper and lower partitions. A feeding device is installed at the top of the preheating chamber. The feeding device includes a feeding hopper, which is installed at the top of the preheating chamber. A U-shaped conduit is connected to the top of the feeding hopper. A discharge device is installed at the bottom of the preheating chamber. The discharge device includes a discharge pipe, which is installed at the bottom of the preheating chamber. A secondary heat dissipation device is installed at the lower end of the discharge pipe.

[0009] Preferably, the slurry atomization device includes an atomizing pump, which is installed in the middle of the atomizing pipe. An atomizing nozzle is fixedly installed at one end of the atomizing pipe that connects to the top of the drying tower. A plurality of atomizing holes are provided at the bottom of the atomizing nozzle. The end of the slurry pipe away from the preheating chamber leads to the pulping workshop.

[0010] Preferably, the particle discharge device includes a second blower, which is installed at the lower end of the conveying pipe. The conveying pipe is vertically arranged on one side of the drying tower. The separation pipe is connected to the lower end of the conveying pipe, and the U-shaped guide tube is connected to the upper end of the conveying pipe. An air outlet is provided on the top of the U-shaped guide tube near the feeding hopper, and a filter screen is provided inside the air outlet.

[0011] Preferably, the upper side of the preheating chamber outer wall of the upper partition is provided with a feed inlet, the lower side of the preheating chamber outer wall of the lower partition is provided with a discharge outlet, a temperature sensor is provided between the upper partition and the lower partition, the temperature sensor is installed in the gap between each heat exchange tube, a terminal controller is installed on the top surface of the inner wall of the preheating chamber, and a temperature sensing wire is connected between the terminal controller and the temperature sensor.

[0012] Preferably, the feeding device includes a feeding conduit, one end of which is connected to the feeding port on the outer wall of the preheating chamber, and the other end is connected upward to the bottom of the feeding hopper. An opening and closing flap is rotatably installed at the feeding port of the preheating chamber. A first hydraulic rod is installed on the top surface of the inner wall of the preheating chamber, and a lifting plate is installed at the lower end of the first hydraulic rod. The lifting plate is slidably installed on the inner wall of the preheating chamber above the upper partition.

[0013] Preferably, the feeding device includes a positioning tube, which is embedded in the top of the preheating chamber. A pressure sensor is installed inside the positioning tube and is electrically connected to the terminal controller. A pressure rod is provided on the top surface of the pressure sensor, and a pressure-receiving platform is installed on the upper end of the pressure rod. A circular hole is provided on the bottom surface of the feeding hopper, and the pressure-receiving platform is slidably installed in the circular hole on the bottom surface of the feeding hopper. A spring is provided at the bottom of the pressure-receiving platform.

[0014] Preferably, the discharge device includes a discharge conduit, one end of which is connected to the discharge port on the outer wall of the preheating chamber, and the other end is connected downward to the top of the discharge pipe. A second hydraulic rod is installed on the bottom surface of the inner wall of the preheating chamber, and a lifting frame is installed on the upper end of the second hydraulic rod. The lifting frame is slidably installed on the inner wall of the preheating chamber below the lower partition.

[0015] Preferably, the discharge device includes a vertical pole, which is installed at the center of the bottom surface of the inner wall of the preheating chamber. The vertical pole extends upward to the lower end of the heat exchange tube. A sealing rubber sheet is installed on the top surface of the lifting frame, and the upper end of the vertical pole pushes upward to the center of the bottom surface of the sealing rubber sheet.

[0016] Preferably, the secondary heat dissipation device includes a secondary heat dissipation chamber, which is installed at the lower end of the feeding pipe. Heat dissipation nets are provided at both ends of the secondary heat dissipation chamber. A feeding pipe is installed at the bottom of the secondary heat dissipation chamber, and a feeding pump is installed in the middle of the feeding pipe. The feeding pipe leads to the dry pressing workshop.

[0017] The production process using the above-mentioned CVD silicon carbide heater processing system includes S1-S5;

[0018] S1. First, according to the formula of silicon carbide heater, the production personnel use an electronic balance to accurately weigh the carbon source, silicon source and other necessary additives and use a mixer to initially mix them. The prepared raw materials and liquid (such as water or organic solvent) are added to a high-shear mixer to mix the powder and liquid to achieve the required slurry viscosity. Then, a ball mill is used to further refine the slurry to make its particle size smaller and achieve the requirements of uniformity and flowability.

[0019] S2. Next, the production staff starts the No. 1 blower and electric heater. The electric heater heats the air in the hot air tower and dries the tower under the action of the No. 1 blower. After the drying tower reaches the specified temperature, the slurry pump is started. The slurry pump draws the slurry in the ball mill into the slurry pipe and injects it into the preheating chamber. Then the atomizing pump is started. The atomizing pump injects the slurry in the preheating chamber into the atomizing nozzle through the atomizing pipe and sprays it out. The sprayed slurry particles are quickly dried in the drying tower. Then the No. 2 blower is started. The No. 2 blower blows the particles at the bottom of the drying tower into the feeding hopper in sequence through the separation pipe, the conveying pipe and the U-shaped guide pipe.

[0020] S3. As high-temperature particles accumulate in the feeding hopper, the pressure platform triggers the pressure sensor downward. When the terminal controller receives a pressure signal released by the pressure sensor to a certain value, the terminal controller controls the first hydraulic rod to drive the lifting plate to rise, and the opening and closing flap unfolds. The high-temperature particles in the feeding hopper rush into the heat exchange tube, and the pressure signal released by the pressure sensor weakens accordingly. The terminal controller controls the first hydraulic rod again to drive the lifting plate to fall and close the opening and closing flap. At the same time, the high-temperature particles in the heat exchange tube heat the slurry in the preheating chamber through the heat exchange tube, and simultaneously preheat the slurry and perform preliminary cooling of the particles.

[0021] S4. The terminal controller senses the temperature of the slurry in the preheating chamber in real time through the temperature sensor. When the slurry is heated to the specified temperature, the terminal controller controls the second hydraulic rod to drive the lifting frame to descend. The lifting frame stretches the sealing rubber, and then the particles in the heat exchange tube fall into the secondary heat dissipation chamber along the discharge guide and discharge pipe for natural cooling.

[0022] S5. After the particles in the secondary heat dissipation chamber have completely cooled, start the feed pump to feed the particles into the mold of the dry press along the feed pipe. Start the dry press to press the particles into the required heater shape using high pressure. Then, take out the shell from the mold and put the shell into a high-temperature furnace. Pre-fire the shell at low temperature to remove organic matter and binder, and enhance the initial strength of the material. Then, put the shell into an atmosphere furnace and heat it under a controlled atmosphere (such as hydrogen, nitrogen, etc.) to promote the reaction between silicon and carbon, so that the silicon in the raw material reacts with carbon to form silicon carbide. Then, put the shell back into the high-temperature furnace for crystallization at high temperature to stabilize the crystal structure of silicon carbide and achieve ideal electrical and thermal properties. Then, use a grinding machine and a polishing machine to perform surface treatment on the crystallized silicon carbide heater in sequence to remove the surface rough layer and achieve the required precision and surface smoothness. Finally, perform various performance tests on the processed silicon carbide heater to ensure that it meets the design requirements.

[0023] The beneficial effects of this invention are as follows: Before spray granulation, the slurry is introduced into the preheating chamber through the slurry pipe and then into the drying tower for spray granulation. On the other hand, the high-temperature particles in the drying tower are introduced into the heat exchange tube through the particle discharge device and the feeding device at the top of the preheating chamber. The high-temperature particles heat the slurry in the preheating chamber through the heat exchange tube, and at the same time, the slurry in turn preheats the high-temperature particles, so as to achieve the effect of slurry preheating and particle cooling at the same time. This effectively reduces the energy input in the process of preheating slurry and cooling particles, reduces the energy consumption in the overall production process, and thus reduces production costs. At the same time, the preheating and cooling steps can also shorten the overall production cycle, thereby improving production efficiency and increasing the utilization rate of production capacity. Attached Figure Description

[0024] Figure 1 A front structural diagram provided for this invention;

[0025] Figure 2 A schematic diagram of the rear structure provided for this invention;

[0026] Figure 3 This is a cross-sectional view of the drying tower and hot air tower provided by the present invention;

[0027] Figure 4 A side view provided for this invention;

[0028] Figure 5 This is a cross-sectional view of the secondary heat dissipation chamber provided by the present invention;

[0029] Figure 6 This is a schematic diagram of the inlet and outlet heat exchange module structure provided by the present invention;

[0030] Figure 7 This is a cross-sectional view of the feeding hopper provided by the present invention;

[0031] Figure 8 This is a schematic diagram of the internal structure of the preheating chamber provided by the present invention;

[0032] Figure 9 This is a schematic diagram of the opening and closing flap provided by the present invention;

[0033] Figure 10 This is a schematic diagram of the opening of the sealing rubber provided by the present invention;

[0034] Figure 11 This is a cross-sectional view of the inlet and outlet heat exchange module provided by the present invention;

[0035] Figure 12 Provided by the present invention Figure 11 Detail image A;

[0036] Figure 13 Provided by the present invention Figure 11 Detail image B;

[0037] Figure 14 This is a schematic diagram of the temperature sensor installation provided by the present invention.

[0038] In the diagram: Drying tower 11, hot air tower 121, electric heater 122, blower No. 1 123, atomizing pipe 131, atomizing pump 132, atomizing nozzle 133, slurry pipe 141, slurry pump 142, separation pipe 151, conveying pipe 152, blower No. 2 153, U-shaped duct 154, air outlet 155, preheating chamber 161, upper partition 162, lower partition 163, heat exchange pipe 164, feeding hopper 165, feeding duct 166, discharging pipe 167. Feeding conduit; 168. Opening and closing flap; 171. First hydraulic rod; 172. Lifting plate; 173. Positioning tube; 174. Pressure sensor; 175. Pressing rod; 176. Pressure-bearing platform; 177. Spring; 178. Upright pole; 181. Second hydraulic rod; 182. Lifting frame; 183. Sealing rubber; 184. Temperature sensor; 185. Temperature sensing wire; 186. Terminal controller; 187. Secondary heat dissipation chamber; 191. Feeding pipe; 192. Feeding pump; 193. Detailed Implementation

[0039] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0040] Example 1, as Figure 1 - Figure 8 As shown, the CVD silicon carbide heater processing system and its process in the first aspect embodiment of the present invention include a spray granulation module and a feed and discharge heat exchange module.

[0041] The spray granulation module includes a drying tower 11, a hot air tower 121 installed on the side of the drying tower 11, the upper end of the hot air tower 121 connected to the upper part of the drying tower 11, an electric heater 122 installed inside the hot air tower 121, a blower 123 installed at the bottom of the hot air tower 121, a slurry atomizing device connected to the upper end of the drying tower 11, the slurry atomizing device including an atomizing pipe 131, one end of the atomizing pipe 131 connected to the top of the drying tower 11, a particle discharge device installed at the bottom of the drying tower 11, the particle discharge device including a separation pipe 151, one end of the separation pipe 151 connected to the bottom of the drying tower 11, the other end connected to a conveying pipe 152, and the conveying pipe 152 connected to a U-shaped conduit 154;

[0042] The inlet and outlet heat exchange module includes a preheating chamber 161. A slurry pipe 141 is installed on one side of the preheating chamber 161, and an atomizing pipe 131 is connected to the other side. An upper baffle 162 and a lower baffle 163 are installed on the upper and lower inner walls of the preheating chamber 161, respectively. A heat exchange pipe 164 is installed between the upper baffle 162 and the lower baffle 163. A feeding device is installed on the top of the preheating chamber 161. The feeding device includes a feeding hopper 165, which is installed on the top of the preheating chamber 161. A U-shaped conduit 154 is connected to the top of the feeding hopper 165. A discharge device is installed at the bottom of the preheating chamber 161. The discharge device includes a discharge pipe 167, which is installed at the bottom of the preheating chamber 161. A secondary heat dissipation device is installed at the lower end of the discharge pipe 167.

[0043] In the above embodiment, it should be noted that the No. 1 blower 123 is externally connected to a power supply and control system, the electric heater 122 is connected to a microcontroller and a power supply, and the microcontroller is connected to a thermistor. The thermistor is installed inside the hot air tower 121. The microcontroller controls the start of the electric heater 122 to heat the air inside the hot air tower 121, and then starts the No. 1 blower 12 to send the air inside the hot air tower 121 into the drying tower 11. After the drying tower 11 reaches the specified temperature, the slurry pump 142 is started. The slurry pump 142 draws the slurry in the slurry preparation workshop into the slurry pipe 141 and injects it into the preheating chamber 161. Then, the atomizing pump 132 is started. The atomizing pump 132 introduces the slurry in the preheating chamber 161 into the drying tower 11 through the atomizing pipe 131. The sprayed slurry particles are rapidly dried in the drying tower 11 to form high-temperature particles, so as to achieve the effect of spray granulation.

[0044] Before spray granulation, the slurry is introduced into the preheating chamber 161 through the slurry pipe 141 and then into the drying tower 11 for spray granulation. On the other hand, the high-temperature particles in the drying tower 11 are introduced into the heat exchange tube 164 through the particle discharge device and the feeding device at the top of the preheating chamber 161. The high-temperature particles heat the slurry in the preheating chamber 161 through the heat exchange tube 164, and at the same time, the slurry in turn preheats the high-temperature particles, so as to achieve the effect of slurry preheating and particle cooling at the same time. This effectively reduces the energy input in the process of preheating slurry and cooling particles, reduces the energy consumption in the overall production process, and thus reduces production costs. At the same time, the preheating and cooling steps can also shorten the overall production cycle, thereby improving production efficiency and increasing the utilization rate of capacity.

[0045] After the high-temperature particles are initially cooled in the heat exchange tube 164, the particles are discharged from the heat exchange tube 164 to the secondary heat dissipation device by activating the discharge device. The particles are then further cooled by the secondary heat dissipation device until they are completely cooled before being transported to the dry pressing workshop.

[0046] Example 2, as Figure 1 - Figure 4As shown, the CVD silicon carbide heater processing system and its process include Example 1. In addition, the slurry atomization device includes an atomizing pump 132, which is installed in the middle of the atomizing pipe 131. An atomizing nozzle 133 is fixedly installed at one end of the atomizing pipe 131 that is connected to the top of the drying tower 11. Several atomizing holes are provided at the bottom of the atomizing nozzle 133. The end of the slurry pipe 141 away from the preheating chamber 161 leads to the pulping workshop. The particle discharge device includes a second blower 153, which is installed at the lower end of the conveying pipe 152. The conveying pipe 152 is vertically arranged on one side of the drying tower 11. The separation pipe 151 is connected to the lower side of the conveying pipe 152. The U-shaped conduit 154 is connected to the upper end of the conveying pipe 152. An air outlet 155 is provided on the side of the top of the U-shaped conduit 154 near the feeding hopper 165. A filter screen is provided inside the air outlet 155.

[0047] In the above embodiments, it should be noted that the atomizing nozzle 133 is an existing nozzle structure that can spray out uniform slurry droplets. The atomizing pump 132 is connected to an external power supply and control system. By starting the atomizing pump 132, the atomizing pump 132 injects the slurry in the preheating chamber 161 into the atomizing nozzle 133 through the atomizing pipe 131 and sprays it out. The sprayed slurry particles are rapidly dried in the drying tower 11, and the dried particles naturally fall to the bottom of the drying tower 11.

[0048] The No. 2 blower 153 is connected to an external power supply and control system. The filter screen installed in the air outlet 155 has a pore size smaller than the diameter of the high-temperature particles. The filter screen of the air outlet 155 has the function of intercepting high-temperature particles. As high-temperature particles continue to accumulate at the bottom of the drying tower 11, the high-temperature particles flow into the lower end of the separation pipe 151 along the separation pipe 151. By controlling the start of the No. 2 blower 153, the high-temperature particles at the lower end of the separation pipe 151 are blown up. The blown high-temperature particles are blown into the feeding hopper 165 along the U-shaped guide tube 154. The air blowing up the high-temperature particles is discharged along the air outlet 155, so as to achieve the effect of guiding the high-temperature particles in the drying tower 11 into the feeding hopper 165.

[0049] Example 3, as Figure 4 - Figure 14As shown, the CVD silicon carbide heater processing system and its process include Example 1. Furthermore, a feed inlet is provided on the outer wall of the preheating chamber 161 on the upper side of the upper partition 162, and a discharge outlet is provided on the outer wall of the preheating chamber 161 on the lower side of the lower partition 163. A temperature sensor 185 is installed between the upper partition 162 and the lower partition 163, and the temperature sensor 185 is installed in the gap between each heat exchange tube 164. A terminal controller 187 is installed on the top surface of the inner wall of the preheating chamber 161, and a temperature sensing wire 186 connects the terminal controller 187 and the temperature sensor 185. The feeding device includes a feeding conduit 166, one end of which is connected to the feeding port on the outer wall of the preheating chamber 161, and the other end is connected upward to the bottom of the feeding hopper 165. An opening and closing flap 171 is rotatably installed at the feeding port of the preheating chamber 161. A first hydraulic rod 172 is installed on the top surface of the inner wall of the preheating chamber 161, and a lifting plate 173 is installed at the lower end of the first hydraulic rod 172. The lifting plate 173 is slidably installed on the inner wall of the preheating chamber 161 above the upper partition 162. The feeding device also includes a positioning tube 174, which is embedded in the top of the preheating chamber 161. The positioning tube 174 houses a pressure sensor 175, which is electrically connected to the terminal controller 187. A pressure rod 176 is mounted on the top surface of the pressure sensor 175, and a pressure-bearing platform 177 is mounted on the upper end of the pressure rod 176. A circular hole is provided on the bottom surface of the feeding hopper 165, and the pressure-bearing platform 177 is slidably installed within this hole. A spring 178 is located at the bottom of the pressure-bearing platform 177. The discharge device includes a discharge conduit 168, one end of which is connected to the discharge port on the outer wall of the preheating chamber 161, and the other end... The top of the lower connecting discharge pipe 167 is connected to the bottom of the inner wall of the preheating chamber 161. A second hydraulic rod 182 is installed on the bottom of the second hydraulic rod 182. A lifting frame 183 is installed on the upper end of the second hydraulic rod 182. The lifting frame 183 is slidably installed on the inner wall of the preheating chamber 161 below the lower partition 163. The discharge device includes a vertical rod 181, which is installed in the center of the bottom of the inner wall of the preheating chamber 161. The vertical rod 181 extends upward to the lower end of the heat exchange tube 164. A sealing rubber 184 is installed on the top surface of the lifting frame 183. The upper end of the vertical rod 181 pushes the center of the bottom surface of the sealing rubber 184 upward.

[0050] In the above embodiments, it should be noted that the pressure sensor 175 is a device that can measure pressure and convert it into an electrical signal, and is widely used in hydraulics, pneumatics, automation control, industrial process monitoring and other fields, and belongs to the prior art; the temperature sensor 185 is a device used to measure temperature and convert it into a processable electrical signal, and belongs to the prior art; a torsion spring is provided at the pivot of the opening and closing flap 171, and the torsion spring applies a force that continuously deflects inward to the opening and closing flap 171. When the lifting plate 173 moves downward, it can push the opening and closing flap 171 to overcome the force applied by the torsion spring and close the opening and closing flap 171; the heat exchange tube 164 is made of a metal material with good thermal conductivity; the sealing rubber 184 is made of a rubber material with high temperature resistance and good tensile properties; the first hydraulic rod 172 and the second hydraulic rod 182 are both externally powered and electrically connected to the terminal controller 187;

[0051] As high-temperature particles accumulate in the feeding hopper 165, the pressure platform 177 triggers the pressure sensor 175 downwards. When the terminal controller 187 receives a pressure signal released by the pressure sensor 175 to a certain value, the terminal controller 187 controls the first hydraulic rod 172 to drive the lifting plate 173 to rise, and the opening and closing flap 171 unfolds. The high-temperature particles in the feeding hopper 165 rush into the heat exchange tube 164, and the pressure signal released by the pressure sensor 175 weakens accordingly. The terminal controller 187 then controls the first hydraulic rod 172 to drive the lifting plate 173 to fall and close the opening and closing flap 171. At the same time, the high-temperature particles in the heat exchange tube 164 preheat the slurry in the preheating chamber 161 through the heat exchange tube 164 to achieve the effect of simultaneously preheating the slurry and initially cooling the particles.

[0052] The terminal controller 187 senses the temperature of the slurry in the preheating chamber 161 in real time through the temperature sensor 185. When the slurry is heated to the specified temperature, the terminal controller 187 controls the second hydraulic rod 182 to drive the lifting frame 183 to descend. The lifting frame 183 stretches the sealing rubber 184 to achieve the effect of causing the particles in the heat exchange tube 164 to fall into the discharge pipe 167 along the discharge guide 168.

[0053] The terminal controller 187 includes the following electronic components:

[0054] (1) Analog signal conditioning circuit: used to receive analog signals from pressure and temperature sensors, which may need to be amplified, filtered and converted for transmission to the control system;

[0055] (2) Analog-to-digital converter (ADC): Converts analog signals into digital signals for subsequent digital processing;

[0056] (3) Sensor power supply circuit: provides stable voltage and current to the sensor to ensure signal accuracy;

[0057] (4) Microcontroller (MCU): It is responsible for receiving sensor signals, performing data processing and analysis, executing control algorithms, controlling the action of the hydraulic system, and adjusting the output according to the feedback from the sensors;

[0058] (5) Drive circuit: a motor or actuator that drives the hydraulic rod according to the control signal.

[0059] Example 4, as Figure 4 and Figure 5 As shown, the CVD silicon carbide heater processing system and its process include Example 3. In addition, the secondary heat dissipation device includes a secondary heat dissipation chamber 191, which is installed at the lower end of the feed pipe 167. Heat dissipation nets are provided at both ends of the secondary heat dissipation chamber 191 in the horizontal direction. A feed pipe 192 is installed at the bottom of the secondary heat dissipation chamber 191. A feed pump 193 is installed in the middle of the feed pipe 192. The feed pipe 192 leads to the dry pressing workshop.

[0060] In the above embodiments, it should be noted that the heat dissipation nets provided on both sides of the secondary heat dissipation chamber 191 can facilitate the exchange of air inside and outside the secondary heat dissipation chamber 191, so that the particles inside the secondary heat dissipation chamber 191 can be cooled naturally.

[0061] The particles in the feed pipe 167 will continue to fall into the secondary heat dissipation chamber 191 for natural cooling. After the particles in the secondary heat dissipation chamber 191 are completely cooled, the feed pump 193 is started to feed the particles into the mold of the dry press along the feed pipe 192, and then the next step can be carried out.

[0062] The production process of the CVD silicon carbide heater processing system of the present invention is as follows: First, the production personnel use an electronic balance to accurately weigh the carbon source, silicon source and other necessary additives according to the formula of the silicon carbide heater, and use a mixer to initially mix them. The prepared raw materials and liquid (such as water or organic solvent) are added to a high-shear mixer to mix the powder and liquid to achieve the required slurry viscosity. Then, a ball mill is used to further refine the slurry to make its particle size smaller and achieve the requirements of uniformity and flowability.

[0063] Next, the production staff started the No. 1 blower 123 and the electric heater 122. The electric heater 122 heated the air in the hot air tower 121 and dried the tower 11 under the action of the No. 1 blower 123. After the drying tower 11 reached the specified temperature, the slurry pump 142 was started. The slurry pump 142 drew the slurry in the ball mill into the slurry pipe 141 and injected it into the preheating chamber 161. Then, the atomizing pump 132 was started. The atomizing pump 132 injected the slurry in the preheating chamber 161 into the atomizing nozzle 133 through the atomizing pipe 131 and sprayed it out. The sprayed slurry particles dried rapidly in the drying tower 11. Then, the No. 2 blower 153 was started. The No. 2 blower 153 blows the particles at the bottom of the drying tower 11 into the feeding hopper 165 in sequence through the separation pipe 151, the conveying pipe 152 and the U-shaped guide pipe 154.

[0064] As high-temperature particles accumulate in the feeding hopper 165, the pressure platform 177 triggers the pressure sensor 175 downwards. When the terminal controller 187 receives a pressure signal released by the pressure sensor 175 to a certain value, the terminal controller 187 controls the first hydraulic rod 172 to drive the lifting plate 173 to rise, and the opening and closing flap 171 unfolds. The high-temperature particles in the feeding hopper 165 rush into the heat exchange tube 164, and the pressure signal released by the pressure sensor 175 weakens accordingly. The terminal controller 187 then controls the first hydraulic rod 172 to drive the lifting plate 173 to fall and close the opening and closing flap 171. At the same time, the high-temperature particles in the heat exchange tube 164 preheat the slurry in the heat exchange tube 164, thus preheating the slurry and initially cooling the particles.

[0065] The terminal controller 187 senses the temperature of the slurry in the preheating chamber 161 in real time through the temperature sensor 185. When the slurry is heated to the specified temperature, the terminal controller 187 controls the second hydraulic rod 182 to drive the lifting frame 183 to descend. The lifting frame 183 stretches the sealing rubber 184, and then the particles in the heat exchange tube fall into the secondary heat dissipation chamber 191 along the discharge guide pipe 168 and the discharge pipe 167 for natural cooling.

[0066] After the particles in the secondary heat dissipation chamber 191 have completely cooled, the feed pump 193 is started to feed the particles into the mold of the dry press along the feed pipe 192. The dry press is started to press the particles into the required heater shape using high pressure. Then, the shell is taken out of the mold and placed in a high-temperature furnace. The shell is pre-fired at a low temperature to remove organic matter and binders, and to enhance the initial strength of the material. The shell is then placed in an atmosphere furnace and heated under a controlled atmosphere (such as hydrogen, nitrogen, etc.) to promote the reaction between silicon and carbon, so that the silicon in the raw material reacts with carbon to form silicon carbide. The shell is then placed in a high-temperature furnace again for crystallization at high temperature to stabilize the crystal structure of silicon carbide and achieve ideal electrical and thermal properties. Then, the crystallized silicon carbide heater is surface-treated by a grinding machine and a polishing machine in sequence to remove the surface rough layer and achieve the required precision and surface smoothness. Finally, the processed silicon carbide heater is subjected to various performance tests to ensure that it meets the design requirements.

[0067] The above description is merely a preferred embodiment of the present invention. Any person skilled in the art can modify the present invention or modify it into an equivalent technical solution using the technical solutions described above. Therefore, any simple modifications or equivalent substitutions made based on the technical solutions of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A CVD silicon carbide heater processing system, comprising a spray granulation module and an infeed / outfeed heat exchange module, characterized in that: The spray granulation module includes a drying tower (11), a hot air tower (121) is installed on the side of the drying tower (11), the upper end of the hot air tower (121) is connected to the upper part of the drying tower (11), an electric heater (122) is installed inside the hot air tower (121), a blower (123) is installed at the bottom of the hot air tower (121), a slurry atomizing device is connected to the upper end of the drying tower (11), the slurry atomizing device includes an atomizing pipe (131), one end of the atomizing pipe (131) is connected to the top of the drying tower (11), a particle discharge device is installed at the bottom of the drying tower (11), the particle discharge device includes a separation pipe (151), one end of the separation pipe (151) is connected to the bottom of the drying tower (11), and the other end is connected to a conveying pipe (152), the conveying pipe (152) is connected to a U-shaped conduit (154); The inlet and outlet heat exchange module includes a preheating chamber (161). A slurry pipe (141) is installed on one side of the preheating chamber (161), and an atomizing pipe (131) is connected to the other side. An upper partition (162) and a lower partition (163) are respectively installed on the upper and lower inner walls of the preheating chamber (161). A heat exchange pipe (164) is installed between the upper partition (162) and the lower partition (163). A feeding device is installed on the top of the preheating chamber (161). The feeding device includes a feeding hopper (165), which is installed on the top of the preheating chamber (161). The U-shaped conduit (154) is connected to the top of the feeding hopper (165). A discharge device is installed at the bottom of the preheating chamber (161). The discharge device includes a discharge pipe (167), which is installed at the bottom of the preheating chamber (161). A secondary heat dissipation device is installed at the lower end of the discharge pipe (167).

2. The CVD silicon carbide heater processing system according to claim 1, characterized in that: The slurry atomizing device includes an atomizing pump (132), which is installed in the middle of an atomizing pipe (131). An atomizing nozzle (133) is fixedly installed at one end of the atomizing pipe (131) that is connected to the top of the drying tower (11). Several atomizing holes are provided at the bottom of the atomizing nozzle (133). The end of the slurry pipe (141) away from the preheating chamber (161) leads to the pulping workshop.

3. The CVD silicon carbide heater processing system according to claim 1, characterized in that: The particle discharge device includes a second blower (153), which is installed at the lower end of the conveying pipe (152). The conveying pipe (152) is vertically arranged on one side of the drying tower (11). The separation pipe (151) is connected to the lower end of the conveying pipe (152). The U-shaped conduit (154) is connected to the upper end of the conveying pipe (152). An air outlet (155) is provided on the top of the U-shaped conduit (154) near the feeding hopper (165). A filter screen is provided inside the air outlet (155).

4. The CVD silicon carbide heater processing system according to claim 1, characterized in that: The upper partition (162) has a feed inlet on the outer wall of the preheating chamber (161) on the upper side, and the lower partition (163) has a discharge outlet on the outer wall of the preheating chamber (161) on the lower side. A temperature sensor (185) is provided between the upper partition (162) and the lower partition (163). The temperature sensor (185) is installed in the gap between each heat exchange tube (164). A terminal controller (187) is installed on the top surface of the inner wall of the preheating chamber (161). A temperature sensing wire (186) is connected between the terminal controller (187) and the temperature sensor (185).

5. The CVD silicon carbide heater processing system according to claim 4, characterized in that: The feeding device includes a feeding conduit (166), one end of which is connected to the feed inlet on the outer wall of the preheating chamber (161), and the other end is connected upward to the bottom of the feeding hopper (165). An opening and closing flap (171) is rotatably installed at the feed inlet of the preheating chamber (161). A first hydraulic rod (172) is installed on the top surface of the inner wall of the preheating chamber (161). A lifting plate (173) is installed at the lower end of the first hydraulic rod (172). The lifting plate (173) is slidably installed on the inner wall of the preheating chamber (161) above the upper partition (162).

6. The CVD silicon carbide heater processing system according to claim 5, characterized in that: The feeding device includes a positioning tube (174), which is embedded in the top of the preheating chamber (161). A pressure sensor (175) is installed inside the positioning tube (174). The pressure sensor (175) is electrically connected to the terminal controller (187). A pressure rod (176) is provided on the top surface of the pressure sensor (175). A pressure receiving platform (177) is installed on the upper end of the pressure rod (176). A round hole is provided on the bottom surface of the feeding hopper (165). The pressure receiving platform (177) is slidably installed in the round hole on the bottom surface of the feeding hopper (165). A spring (178) is provided at the bottom of the pressure receiving platform (177).

7. The CVD silicon carbide heater processing system according to claim 4, characterized in that: The discharge device includes a discharge conduit (168), one end of which is connected to the discharge port on the outer wall of the preheating chamber (161), and the other end is connected downward to the top of the discharge pipe (167). A second hydraulic rod (182) is installed on the bottom surface of the inner wall of the preheating chamber (161), and a lifting frame (183) is installed on the upper end of the second hydraulic rod (182). The lifting frame (183) is slidably installed on the inner wall of the preheating chamber (161) below the lower partition (163).

8. The CVD silicon carbide heater processing system according to claim 7, characterized in that: The discharge device includes a vertical pole (181), which is installed at the center of the bottom surface of the inner wall of the preheating chamber (161). The vertical pole (181) extends upward to the lower end of the heat exchange tube (164). A sealing rubber sheet (184) is installed on the top surface of the lifting frame (183). The upper end of the vertical pole (181) pushes the sealing rubber sheet (184) upward to the center of the bottom surface of the sealing rubber sheet (184).

9. The CVD silicon carbide heater processing system according to claim 1, characterized in that: The secondary heat dissipation device includes a secondary heat dissipation chamber (191), which is installed at the lower end of the feed pipe (167). Heat dissipation nets are provided at both ends of the secondary heat dissipation chamber (191). A feed pipe (192) is installed at the bottom of the secondary heat dissipation chamber (191). A feed pump (193) is installed in the middle of the feed pipe (192). The feed pipe (192) leads to the dry pressing workshop.

10. A manufacturing process using the CVD silicon carbide heater processing system described in claims 1-9, comprising steps S1-S5, characterized in that: S1. First, according to the formula of silicon carbide heater, the production personnel use an electronic balance to accurately weigh the carbon source, silicon source and other necessary additives and use a mixer to initially mix them. The prepared raw materials and liquid (such as water or organic solvent) are added to a high-shear mixer to mix the powder and liquid to achieve the required slurry viscosity. Then, a ball mill is used to further refine the slurry to make its particle size smaller and achieve the requirements of uniformity and flowability. S2. Next, the production staff starts the No. 1 blower (123) and the electric heater (122). The electric heater (122) heats the air in the hot air tower (121) and, under the action of the No. 1 blower (123), the air dries in the drying tower (11). After the drying tower (11) reaches the specified temperature, the slurry pump (142) is started. The slurry pump (142) draws the slurry in the ball mill into the slurry pipe (141) and injects it into the preheating chamber (161). Then, the atomizing pump (1) is started. 32) The atomizing pump (132) injects the slurry in the preheating chamber (161) into the atomizing nozzle (133) through the atomizing pipe (131) and sprays it out. The sprayed slurry particles are quickly dried in the drying tower (11). Then the second blower (153) is started. The second blower (153) blows the particles at the bottom of the drying tower (11) into the feeding hopper (165) through the separation pipe (151), the conveying pipe (152) and the U-shaped guide pipe (154) in sequence. S3. As high-temperature particles accumulate in the feeding hopper (165), the pressure platform (177) triggers the pressure sensor (175) downward. When the terminal controller (187) receives the pressure signal released by the pressure sensor (175) to a certain value, the terminal controller (187) controls the first hydraulic rod (172) to drive the lifting plate (173) to rise, and the opening and closing flap (171) unfolds. The high-temperature particles in the feeding hopper (165) rush into the heat exchange tube (164), and the pressure signal released by the pressure sensor (175) weakens accordingly. The terminal controller (187) controls the first hydraulic rod (172) again to drive the lifting plate (173) to fall and close the opening and closing flap (171). At the same time, the high-temperature particles in the heat exchange tube (164) preheat the slurry in the preheating chamber (161) through the heat exchange tube (164), and simultaneously preheat the slurry and initially cool the particles. S4. The terminal controller (187) senses the temperature of the slurry in the preheating chamber (161) in real time through the temperature sensor (185). When the slurry is heated to the specified temperature, the terminal controller (187) controls the second hydraulic rod (182) to drive the lifting frame (183) to descend. The lifting frame (183) stretches the sealing rubber (184). Then the particles in the heat exchange tube fall into the secondary heat dissipation chamber (191) along the discharge guide pipe (168) and discharge pipe (167) for natural cooling. S5. After the particles in the secondary heat dissipation chamber (191) have completely cooled, start the feed pump (193) to feed the particles into the mold of the dry press along the feed pipe (192). Start the dry press to press the particles into the required heater shape using high pressure. Then take out the shell from the mold and put the shell into a high-temperature furnace. Pre-burn the shell at low temperature to remove organic matter and binder, and enhance the initial strength of the material. Then put the shell into an atmosphere furnace and heat it under a controlled atmosphere (such as hydrogen, nitrogen, etc.) to promote the reaction between silicon and carbon, so that the silicon in the raw material reacts with carbon to form silicon carbide. Then put the shell back into the high-temperature furnace and crystallize it at high temperature to stabilize the crystal structure of silicon carbide and achieve ideal electrical and thermal properties. Then use a grinding machine and a polishing machine to perform surface treatment on the crystallized silicon carbide heater in sequence to remove the surface rough layer and achieve the required precision and surface smoothness. Finally, perform various performance tests on the processed silicon carbide heater to ensure that it meets the design requirements.

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