Electric heating tail gas treatment system
By using reaction chambers, lining covers and thermally conductive components made of aluminum nitride material, the corrosion problem of existing exhaust gas treatment devices when dealing with fluorine ions and corrosive gases is solved, extending service life and reducing costs.
Patent Information
- Application Number
- CN202411695270.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-25
- Publication Date
- 2025-02-25
AI Technical Summary
When existing exhaust gas treatment devices deal with fluorine ions and corrosive gases generated in semiconductor factories, the reaction chamber and heating rod are prone to corrosion, resulting in short maintenance cycles and high cost.
The reaction chamber, lining cover, air inlet and thermally conductive components made of aluminum nitride material extends the service life and improves structural strength through the corrosion resistance and high thermal conductivity of aluminum nitride.
The service life of the reaction chamber, lining cover and heating coil is extended, maintenance and replacement costs are reduced, while improving the overall load-bearing capacity and structural strength of the processing system.
Smart Images
Figure CN119499850A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the field of semiconductors, and in particular to an electric heating tail gas treatment system. Background Art
[0002] The main function of the waste gas treatment device is to treat and purify the waste gas generated to reduce the negative impact on the environment and human health. These devices are usually used in industrial production, semiconductor factories, photovoltaic factories, and other waste gas treatment facilities. The working principle is: first turn on the heating rod to heat the reaction chamber. When the temperature in the reaction chamber reaches the working temperature, the waste gas to be treated is sent into the reaction chamber and oxygen is introduced to react with it. After sufficient reaction, the reaction product is sent to the water tank for water washing treatment to ensure that the gas discharged later can meet environmental regulations and standards.
[0003] This type of waste gas treatment device has the following defects: 1. Since the waste gas from CVD, DI FF, I MP and cleaning processes in semiconductor factories contains a large amount of fluorine ions and corrosive gases, it has a strong corrosion effect on the existing stainless steel reaction chamber. If it is damaged by corrosion, the entire reaction chamber needs to be replaced, which is too costly. 2. The heating rod is located in the reaction chamber and is in direct contact with the fluorine ions and corrosive gases contained in the waste gas, which makes it easy to be corroded, resulting in a short maintenance cycle and a short service life of the heating rod. Summary of the invention
[0004] Based on this, in order to solve the above problems, the present invention provides an electric heating exhaust gas treatment system.
[0005] The purpose of the present invention can be achieved through the following technical solutions:
[0006] An electric heating exhaust gas treatment system comprises a water tank, a water washing tower and a reaction chamber fixed on the water tank, the bottoms of the water washing tower and the reaction chamber are both connected to the water tank, an inner liner cover is provided inside the reaction chamber, a temperature regulating mechanism is provided inside the inner liner cover, an exhaust gas channel surrounding the inner liner cover is formed between the inner wall of the reaction chamber and the outer wall of the inner liner cover, an air inlet connected to the exhaust gas channel is connected to the top of the reaction chamber, a heat-conducting component is provided in the inner liner cover to wrap the temperature regulating mechanism, an air inlet pipe connected to an external air source is connected to the inner liner cover, an air vent is provided on the inner liner cover, an air duct connecting the air vent and the air inlet pipe is provided in the heat-conducting component, and the reaction chamber, the inner liner cover, the air inlet and the heat-conducting component are all made of aluminum nitride.
[0007] The above technical solution is adopted. Since aluminum nitride is a new type of ceramic material, it has excellent thermal conductivity, non-toxicity, corrosion resistance and a thermal expansion coefficient matching that of silicon. In this way, the reaction chamber, the liner cover and the air inlet are all made of aluminum nitride material, which is corrosion-resistant and has a longer service life. Moreover, the heat on the heating surface of the liner cover made of aluminum nitride is uniform, which can reduce the expansion cracking caused by the heat generated by the temperature regulating mechanism, thereby extending the service life of the liner cover. The aluminum nitride reaction chamber improves the overall bearing capacity, increases the structural strength and is not easy to crack. In addition, the heat-conducting component wraps the temperature regulating mechanism. When the temperature regulating mechanism generates heat, the ultra-high thermal conductivity of aluminum nitride can be used to synchronize the temperature rise of the reaction chamber and the liner cover to quickly reach the working temperature. At the same time, it avoids direct contact between the temperature regulating mechanism and the exhaust gas, thereby extending the service life of the temperature regulating mechanism.
[0008] In a specific embodiment of the present invention: the reaction chamber, liner cover and air inlet are all prepared by uniformly mixing aluminum nitride powder and adhesive in a mass ratio of 100:3-8 and adding them into corresponding molds respectively, and gradually applying pressure to 100-300 MPa and pressing for 2-3 minutes to form a embryo, and then firing at a temperature of 1600°C-1800°C for 2-10 hours to form a embryo.
[0009] In a specific implementation manner of the present invention: the adhesive is prepared by uniformly mixing toluene and paraffin in a weight ratio of 3 to 5:1.
[0010] In a specific implementation manner of the present invention: the temperature adjustment mechanism adopts a heating coil.
[0011] In a specific embodiment of the present invention: the heat-conducting component is formed by adding aluminum nitride powder into a corresponding mold, gradually applying pressure to 100-300 MPa and pressing for 2-3 minutes to form a embryo, and then firing at 1600°C-1800°C for 2-10 hours.
[0012] In a specific implementation manner of the present invention: the wall thickness of the reaction chamber is 18 mm to 20 mm, and the wall thickness of the liner cover is 12 mm to 13 mm.
[0013] In a specific implementation manner of the present invention: a first spray system and a second spray system are arranged in the water washing tower from top to bottom, and an air outlet is opened at the top of the water washing tower.
[0014] In a specific implementation manner of the present invention: the reaction chamber is externally covered with a shell, and a heat-insulating sleeve is covered on the shell.
[0015] In a specific implementation manner of the present invention: a drain pipe is connected to the side of the water tank.
[0016] In summary, the reaction chamber, liner cover, air inlet and heat-conducting components in the present invention are all made of aluminum nitride to resist corrosion and extend the service life. Moreover, the liner cover and reaction chamber made of aluminum nitride improve the overall bearing capacity, increase the structural strength and are not easy to crack. In addition, the heat-conducting component wraps the heating coil, which not only avoids the direct contact between the heating coil and the exhaust gas, extending the service life of the heating coil, but also has good thermal conductivity, so that the reaction chamber and the liner cover are heated synchronously and can quickly reach the working temperature. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The present invention will be further described below in conjunction with the accompanying drawings.
[0018] Figure 1 It is a structural schematic diagram of an electric heating tail gas treatment system of the present invention. DETAILED DESCRIPTION
[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0020] See also Figure 1As shown, the present invention is an electric heating exhaust gas treatment system, comprising a reaction chamber 10, an inner liner cover 11 connected to the top wall of the reaction chamber 10, and a temperature regulating mechanism 12 arranged in the inner liner cover 11. An exhaust gas channel 13 surrounding the inner liner cover is formed between the inner wall of the reaction chamber 10 and the outer wall of the inner liner cover 11. An exhaust gas inlet 14 connected to the exhaust gas channel 13 is connected to the top of the reaction chamber 10. Here, the exhaust gas refers to a large amount of fluoride ions and corrosive gases contained in the CVD, DI FF, I MP and cleaning processes of a semiconductor factory. A control valve is connected to the air inlet 14 located outside the reaction chamber. In this embodiment, the reaction chamber 10, the inner liner cover 11 and the air inlet 14 are all made by uniformly mixing aluminum nitride powder and a binder in a mass ratio of 100:3 to 8, and then adding them to the corresponding molds respectively, gradually applying pressure to 100MPa to 300MPa, pressing for 2 to 3 minutes to form an embryo, and then firing at a temperature of 1600℃ to 1800℃ for 2 to 10 hours to form a mold. Since aluminum nitride powder is easy to hydrolyze, the adhesive is toluene and paraffin mixed evenly in a weight ratio of 3 to 5:1. Aluminum nitride is a new type of ceramic material with excellent thermal conductivity, non-toxicity, corrosion resistance and a thermal expansion coefficient matching that of silicon. In this way, the reaction chamber, liner cover and air inlet made of aluminum nitride are corrosion-resistant, have a long service life and low cost. Moreover, the thermal uniformity of the heating surface of the liner cover made of aluminum nitride can reduce the expansion and cracking of the liner cover caused by the heat generated by the temperature regulating mechanism, extend the service life and have good toughness. In addition, the reaction chamber made of aluminum nitride improves the overall bearing capacity, increases the structural strength and is not easy to crack. The wall thickness of the reaction chamber is 18mm to 20mm, and the wall thickness of the liner cover is 12mm to 13mm.
[0021] In this embodiment, the temperature regulating mechanism 12 includes a heating coil 121. The use of the coil has a strong temperature control capability, so that the heating process can be more accurately controlled. A heat-conducting component 122 is provided in the liner cover 11 to wrap the heating coil 121. An air vent 123 is provided on the liner cover 11. A vortex airway 124 communicating with the air vent 123 is provided in the heat-conducting component 122. An air inlet pipe 125 connected to an external air source is connected to the liner cover 11, and the air inlet pipe 125 is communicated with the airway 124.
[0022] In this embodiment, the heat-conducting component 122 is formed by adding aluminum nitride powder into the corresponding mold, and gradually applying pressure to 100-300 MPa for 2-3 minutes to form an embryo, and then firing at 1600℃-1800℃ for 2-10 hours. The heat-conducting component 122 consists of two halves. With this structure, the heat-conducting component wraps the heating coil, and by using the ultra-high thermal conductivity of aluminum nitride, when the heating coil generates heat, the reaction chamber and the liner cover can be heated synchronously, quickly reaching the working temperature of 750-800℃, and at the same time, the heating coil is prevented from directly contacting the exhaust gas, thereby extending the service life of the heating coil.
[0023] When making the reaction chamber 10, the liner cover 11 and the air inlet, the method of dry pressing to form the embryo is adopted. This is because the embryo formed by dry pressing has accurate product size and high mechanical strength after firing. First, aluminum nitride powder and adhesive are added to the corresponding metal mold, and the pressure is slowly applied to 100-300MPa by a press, and pressed for 2-3 minutes, so that the powders are close to each other in the mold and firmly combined by internal friction to form a dense embryo. After that, the embryo is placed in an oven, and the temperature is controlled at 1600℃-1800℃ and fired for 2-10 hours to form. When making the heat-conducting component 122, the method of dry pressing to form the embryo is also adopted. Aluminum nitride powder is added to the corresponding metal mold, and the pressure is slowly applied to 100-300MPa by a press, and pressed for 2-3 minutes to make it a dense embryo. Then, the embryo is placed in an oven, and the temperature is controlled at 1600℃-1800℃ and fired for 2-10 hours to form. Finally, the formed reaction chamber 10, the liner cover 11, the air inlet and the heat-conducting component are connected together by threaded connection.
[0024] A shell 101 is sleeved on the outside of the reaction chamber 10 , and a heat-insulating sleeve 102 is sleeved on the shell 101 .
[0025] In addition, it also includes a water tank 20 and a water washing tower 21. The water washing tower 21 and the reaction chamber 10 are fixed on the water tank 20, and the bottom of the water washing tower 21 and the bottom of the reaction chamber are both connected to the water tank 20. Clean water 201 is placed in the water tank 20. A first spray system 211 and a second spray system 212 are arranged from top to bottom in the water washing tower 21. An air outlet 213 is opened at the top of the water washing tower, and a control valve is connected to the air outlet 213 located outside the water washing tower. A drain pipe 202 is connected to the side of the water tank, and a valve is connected to the drain pipe 202. A liquid level sensor is provided in the water tank, and the liquid level sensor is connected to the valve, which is used to control the liquid level of the water tank and replace the new water in the water tank.
[0026] The above is the electric heating exhaust gas treatment system of the present invention. The specific working principle is that when operating, the heating coil is started first, and the rapid thermal conductivity of the aluminum nitride material is used to synchronously heat the reaction chamber and the liner cover to quickly reach the working temperature of 750-800°C. At the same time, the gas source is turned on, and oxygen enters the reaction chamber 10 from the air inlet pipe 125, through the air duct 124, and through the vent 123. When the temperature of the reaction chamber 10 reaches the working temperature, the control valve on the air inlet 14 is opened, and the exhaust gas enters the reaction chamber 10 through the exhaust gas channel 13 to contact and react with the oxygen. Among them, the vortex gas channel can make the oxygen entering the exhaust gas flow channel form a vortex that can fully contact and react with the exhaust gas to be treated, thereby improving the treatment efficiency.
[0027] After the waste gas to be treated contacts with oxygen in the reaction chamber 10 for sufficient reaction, the reaction product enters the water tank 20 and is sprayed with water mist through the first spray system 211 and the second spray system 212. After circulating cooling and water washing treatment, the clean air is discharged from the air outlet 213 at the top of the water washing tower.
[0028] In summary, the reaction chamber, liner cover, air inlet and heat-conducting components in the present invention are all made of aluminum nitride to resist corrosion and extend the service life. Moreover, the liner cover and reaction chamber made of aluminum nitride improve the overall bearing capacity, increase the structural strength and are not easy to crack. In addition, the heat-conducting component wraps the heating coil, which not only avoids the direct contact between the heating coil and the exhaust gas, extending the service life of the heating coil, but also has good thermal conductivity, so that the reaction chamber and the liner cover are heated synchronously and can quickly reach the working temperature.
[0029] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.
Claims
1. An electric heating tail gas treatment system, comprising a water tank, a water scrubber and a reaction chamber, wherein the bottoms of the water scrubber and the reaction chamber are both connected to the water tank, an inner liner cover is provided inside the reaction chamber, a temperature regulating mechanism is provided inside the inner liner cover, an exhaust gas channel surrounding the inner liner cover is formed between the inner wall of the reaction chamber and the outer wall of the inner liner cover, and an air inlet connected to the exhaust gas channel is connected to the top of the reaction chamber, characterized in that: A heat-conducting component that wraps the temperature regulating mechanism is arranged in the inner liner cover, an air inlet pipe connected to an external air source is connected to the inner liner cover, an air vent is opened on the inner liner cover, an air duct that connects the air vent and the air inlet pipe is arranged in the heat-conducting component, and the reaction chamber, the inner liner cover, the air inlet and the heat-conducting component are all made of aluminum nitride.
2. The electrically heated exhaust gas treatment system according to claim 1, characterized in that: The reaction chamber, liner cover and air inlet are all prepared by uniformly mixing aluminum nitride powder and adhesive in a mass ratio of 100:3-8 and adding them into corresponding molds respectively, and gradually applying pressure to 100-300MPa and pressing for 2-3 minutes to form a embryo, and then firing at a temperature of 1600℃-1800℃ for 2-10 hours to form a embryo.
3. The electrically heated exhaust gas treatment system according to claim 2, characterized in that: The adhesive is prepared by uniformly mixing toluene and paraffin in a weight ratio of 3 to 5:
1.
4. The electrically heated exhaust gas treatment system according to claim 1, characterized in that: The temperature regulating mechanism adopts a heating coil.
5. The electrically heated exhaust gas treatment system according to claim 1, characterized in that: The heat-conducting component is formed by adding aluminum nitride powder into a corresponding mold, gradually applying pressure to 100-300 MPa and pressing for 2-3 minutes to form an embryo, and then firing at 1600° C.-1800° C. for 2-10 hours.
6. The electrically heated exhaust gas treatment system according to claim 1, characterized in that: The water washing tower is provided with a first spray system and a second spray system at intervals from top to bottom, and a gas outlet is provided at the top of the water washing tower.
7. The electrically heated exhaust gas treatment system according to claim 1, characterized in that: The reaction chamber is externally covered with a shell, and the shell is covered with a heat-insulating sleeve.
8. The electrically heated exhaust gas treatment system according to claim 6, characterized in that: A drain pipe is connected to the side of the water tank.
9. The electrically heated tail gas treatment system according to claim 1, characterized in that: The wall thickness of the reaction chamber is 18 mm to 20 mm, and the wall thickness of the lining cover is 12 mm to 13 mm.