Plasma waste gas treatment device

Abstract

According to the plasma waste gas treatment device provided by the utility model, the first air cooling part and the second air cooling part are arranged and are combined with the first circulating medium cooling part, the second circulating medium cooling part and the electronic cooling part, so that the conversion from ultrahigh temperature to low temperature after the waste gas is treated by the plasma is realized; and moreover, anhydrous treatment of semiconductor tail gas can be realized, the problem of water shortage is solved, generation of waste acid water is reduced, and the application prospect is wide.

Description

Technical Field

[0001] The utility model relates to the technical field of gas treatment, in particular to a plasma waste gas treatment device. Background Art

[0002] The scrubber is a core device that dissolves the gas discharged from the semiconductor process in water, converts it into wastewater, and purifies it before discharging it. To start the semiconductor process, hundreds of thousands of tons of industrial water are used every day. Semiconductor companies that are concerned about environmental issues have difficulties in securing water sources and drainage, so the demand for scrubbers without water treatment is increasing.

[0003] Therefore, there is a need to manufacture a semiconductor tail gas treatment device without water treatment, which can simultaneously solve the water shortage and environmental problems faced by semiconductor companies. Utility Model Content

[0004] In order to solve the above technical problems, the utility model provides a plasma waste gas treatment device, which can avoid the problem of large amount of water waste caused by mixing and cooling of decomposed gas after plasma ionization with water, and the generation of waste acid liquid by designing an alternating cooling method of air cooling and circulating cooling medium.

[0005] To achieve this purpose, the utility model adopts the following technical solutions:

[0006] The utility model provides a plasma waste gas treatment device, which comprises, in sequence along the waste gas conveying direction: a first unit, a collecting unit and a second unit, wherein the first unit and the second unit are arranged in parallel on the collecting unit, and the internal spaces of the first unit, the collecting unit and the second unit are connected; the first unit comprises, in sequence along the waste gas conveying direction, a plasma torch part, a gas suction part, a reaction air injection part, a reaction part, a first air cooling part and a first circulating medium cooling part; the gas channel of the first circulating medium cooling part is connected to the collecting unit; the second unit comprises, in sequence along the waste gas conveying direction, a second circulating medium cooling part, a second air cooling part and an electronic cooling part, and the gas channel of the second circulating medium cooling part is connected to the collecting unit.

[0007] Different from the existing plasma waste gas treatment device, the utility model is designed with two first air cooling parts and second air cooling parts, wherein the first air cooling part is used to introduce air into the decomposition gas produced by the reaction part for mixing and cooling. On the one hand, it can avoid the introduction of waste acid produced by the mixture of water medium and decomposition gas, thereby reducing the corrosion to the equipment; on the other hand, it can save a lot of water resources, solving the problem of water shortage in existing enterprises. The second air cooling part can fine-tune the temperature of the gas after being treated by the second circulating medium cooling part. On the one hand, there is no need to set up a circulating medium cooling cavity here, only air inlet holes need to be set, and the requirements for equipment space are relatively low. In addition, the method of fine-tuning the temperature by introducing air has the advantage of greater adjustment sensitivity. Finally, the electronic cooling part is used for further cooling. At this time, since the temperature of the gas is already low, it is difficult to reach the target temperature by continuing to introduce air or circulating medium cooling, or a large cooling area is required. Cooling by the electronic cooling part can not only accurately adjust the temperature, but also consumes relatively less energy.

[0008] It is worth noting that the utility model needs to adopt the cooling sequence of the first air cooling part, the first circulating medium cooling part, the second circulating medium cooling part, the second air cooling part and the electronic cooling part. This is because the temperature of the decomposed gas is high at the beginning. If the first circulating medium cooling part is directly used for cooling, on the one hand, a larger heat exchange area needs to be designed, and the volume of the equipment will be larger; on the other hand, directly using the first circulating medium cooling part to cool the ultra-high temperature decomposed gas is prone to a sudden drop in temperature, resulting in insufficient tolerance of the equipment material; therefore, the method of introducing air into the decomposed gas for mixing and cooling is adopted, which can not only mix evenly, but also effectively reduce the temperature without the need for a large amount of heat exchange area; and then adopting the circulating medium cooling part The subsequent cooling by the ring medium cooling method can avoid the situation where a large amount of exhaust gas is caused by further introduction of a large amount of air; and the temperature of the gas is relatively low at this time, and the use of circulating cooling can reduce the generation of waste acid water and a large amount of exhaust gas; however, before entering the electronic cooling section, in order to ensure the service life of the electronic cooling section, the temperature of the gas needs to be accurately controlled within a specific range, and at this time it is difficult to meet the requirements by only using the second circulating medium cooling section, and continuing to use the circulating cooling method requires a larger equipment space. Therefore, a second air cooling section is set up to adjust the temperature of the gas by introducing air again. It is not only more sensitive, but also has a smaller equipment space, which can match the setting of the plasma exhaust gas treatment device.

[0009] Preferably, the plasma torch part is arranged on the upper part of the gas suction part.

[0010] Preferably, the plasma torch portion comprises a cooling water inlet, a cooling water outlet, a nitrogen inlet, a cathode wiring hole and an anode wiring hole, the cooling water inlet and the cooling water outlet are connected, and the cathode wiring hole and the anode wiring hole are used to arrange the cathode and the anode, respectively.

[0011] Preferably, the diameter of the gas suction portion gradually decreases along the axial direction from top to bottom.

[0012] Preferably, a flange is provided at the lower part of the gas suction part, and a circulating cooling medium injection port and a circulating cooling medium discharge port are provided on the flange; the circulating cooling medium injection port and the circulating cooling medium discharge port are connected and used to transport the circulating cooling medium.

[0013] Preferably, the reaction air injection portion comprises an outer shell layer and an inner wall layer, and the inner wall layer of the reaction air injection portion is provided with holes connected to the air delivery port and evenly distributed.

[0014] The plasma reaction process of the utility model also requires the injection of air, so a reaction air injection part is provided.

[0015] Preferably, the reaction part includes a reaction chamber and a circulating cooling chamber in order from the inside to the outside in the radial direction. A circulating cooling medium is arranged in the circulating cooling chamber, and a circulating cooling medium injection port and a circulating cooling medium discharge port are arranged on the circulating cooling chamber. The circulating cooling medium injection port and the circulating cooling medium discharge port are connected and used to transport the circulating cooling medium.

[0016] The reaction part of the utility model comprises two layers of pipelines, the inner layer of pipeline forms a reaction chamber, and the space between the outer layer of pipeline and the inner layer of pipeline forms a circulating cooling chamber, wherein the space of the inner layer of pipeline is used for gas to produce plasma decomposition reaction, and circulating cooling medium is introduced into the circulating cooling chamber.

[0017] Preferably, the first air-cooling part comprises an outer shell layer and an inner wall layer, and the inner wall layer of the first air-cooling part is provided with holes connected to the air delivery port and evenly distributed.

[0018] In the utility model, air is uniformly sprayed into the interior of the first air cooling part through the uniformly distributed holes, thereby achieving mixing of the air and the gas to be processed.

[0019] Preferably, the first circulating medium cooling part includes a gas channel cavity and a circulating cooling medium cavity in sequence from inside to outside in the radial direction. The second circulating medium cooling part includes a gas channel cavity and a circulating cooling medium cavity in sequence from inside to outside in the radial direction.

[0020] Among them, the circulating cooling medium cavity in the first circulating medium cooling part and the second circulating medium cooling is used to pass the circulating cooling medium to exchange heat with the treated gas, and the circulating cooling cavity is provided with a circulating cooling medium injection port and a circulating cooling medium discharge port, and the circulating cooling medium injection port and the circulating cooling medium discharge port are connected.

[0021] In the utility model, the first circulating medium cooling part and the second circulating medium cooling part are respectively arranged on the upper part of the collecting unit. This is because the temperature of the gas between the two is more moderate. After being cooled by the second circulating medium, the temperature of the gas will be reduced to below 100°C, so a condensed liquid phase will be generated. The condensed liquid phase flows into the collecting unit under the action of gravity, and the interior of the collecting unit is still cooled by introducing air for further cooling.

[0022] Preferably, the second air-cooling part comprises an outer shell layer and an inner wall layer, and the inner wall layer of the second air-cooling part is provided with holes connected to the air delivery port and evenly distributed.

[0023] Preferably, the collection unit includes an air inlet, an air outlet, an air injection port, a circulating cooling medium injection port, a circulating cooling medium discharge port, and a circulating cooling medium cavity; the air inlet is connected to the first circulating medium cooling part in the first unit, and the air outlet is connected to the second circulating medium cooling part in the second unit; the air injection port is arranged around the collection unit, and the cooling medium injection port and the circulating cooling medium discharge port in the collection unit are arranged on the circulating cooling medium cavity. The circulating cooling medium cavity is arranged at the upper position of the collection unit. A temperature sensor is arranged in the upper inner part of the circulating cooling medium cavity.

[0024] Preferably, the plasma exhaust gas treatment device further comprises a liquid phase discharge portion arranged at the bottom of the collecting unit; and a liquid level sensor is arranged on the liquid phase discharge portion.

[0025] Preferably, the liquid phase discharge portion is further provided with a liquid phase pipeline installation component and a liquid phase discharge port; and the liquid phase pipeline installation component is provided with a transparent pipeline.

[0026] Preferably, the liquid phase discharge port is connected to a liquid phase conveying device.

[0027] Preferably, the electronic cooling unit includes a thermoelectric element for gas phase cooling; at least two of the thermoelectric elements are provided; the electronic cooling unit includes an air inlet, an air outlet, a circulating cooling medium inlet and a circulating cooling medium outlet, and the circulating cooling medium inlet and the circulating cooling medium outlet are used to pass the circulating cooling medium.

[0028] The utility model provides a method for anhydrous ionization treatment of semiconductor tail gas. The anhydrous ionization treatment method is carried out by adopting the above-mentioned plasma waste gas treatment device.

[0029] The utility model discloses a method for treating semiconductor tail gas by anhydrous ionization, which can realize anhydrous treatment of semiconductor tail gas and greatly reduce the generation amount of waste acid water.

[0030] As a preferred technical solution of the utility model, the anhydrous ionization treatment method comprises:

[0031] (1) Semiconductor tail gas produces decomposition gas after ionization;

[0032] (2) the decomposed gas is mixed with air and subjected to a first cooling to obtain a first mixed gas;

[0033] (3) The first mixed gas is subjected to second cooling by a first circulating cooling medium to obtain second cooled gas, and the second cooled gas is subjected to third cooling by a second circulating cooling medium to obtain third cooled gas;

[0034] (4) the third cooling gas is mixed with air to perform a fourth cooling to obtain a fourth mixed gas;

[0035] (5) The fourth mixed gas is subjected to fifth cooling by an electronic cooling unit to obtain a purified gas.

[0036] The utility model preferably uses the above process to cool the decomposed gas generated after the semiconductor tail gas is ionized, which can effectively avoid the generation of a large amount of waste water.

[0037] It is worth noting that the utility model needs to adopt air cooling, first circulating cooling medium cooling, second circulating cooling medium cooling, air cooling and thermoelectric element cooling in sequence. This is because the temperature of the decomposed gas is high at the beginning. If the circulating medium is directly used for cooling, on the one hand, a larger heat exchange area needs to be designed, and the volume of the equipment will be larger; on the other hand, directly using the circulating medium to cool the ultra-high temperature decomposed gas is prone to a sudden drop in temperature, resulting in insufficient tolerance of the equipment material; therefore, the method of introducing air into the decomposed gas for mixing and cooling is adopted, which can not only mix evenly, but also effectively reduce the temperature without the need for a large amount of heat exchange area; and then using the circulating medium to cool Subsequent cooling by cooling can avoid the situation where a large amount of exhaust gas is caused by further introduction of a large amount of air; and at this time the temperature of the gas is already relatively low, and the use of circulating cooling can reduce the generation of waste acid water and a large amount of exhaust gas; however, before entering the electronic cooling section, in order to ensure the service life of the electronic cooling section, the temperature of the gas needs to be accurately controlled within a specific range, and at this time it is difficult to meet the requirements by only using circulating media, and continuing to use circulating cooling requires a larger equipment space. Therefore, a second air cooling is set up, and the temperature of the gas is adjusted by introducing air again. This is not only more sensitive, but also has a smaller equipment space, which can match the setting of the plasma exhaust gas treatment device.

[0038] Preferably, the semiconductor exhaust gas comprises any one of silane, hydrogen sulfide, borane, arsine, phosphine or a halogen-containing gas or a combination of at least two thereof, preferably comprises any one of AsH3, B2H6, SiH4, SiH2Cl2, Si2H6, SiHCl3, GeH4, PH3, NH3, H2, H2Se or H2S or a combination of at least two thereof, wherein typical but non-limiting combinations are a combination of AsH3 and B2H6, a combination of SiH4 and B2H6, a combination of AsH3 and SiH4, a combination of SiH2Cl2 and B2H6, a combination of AsH3 and SiH2Cl2, a combination of PH3 and B2H6, a combination of H2Se and PH3, a combination of H2Se and H2S, a combination of AsH3 and H2S, and the like.

[0039] Preferably, the temperature of the semiconductor exhaust gas is 15-25°C, for example, it can be 15°C, 17°C, 18°C, 19°C, 20°C, 21°C, 22°C, 23°C, 24°C or 25°C, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0040] Preferably, the decomposed gas comprises any one of water, carbon dioxide, silicon dioxide or HCl or a combination of at least two thereof, wherein typical but non-limiting combinations are a combination of water and carbon dioxide, a combination of silicon dioxide and carbon dioxide, a combination of water and silicon dioxide, and a combination of water and HCl.

[0041] Preferably, the ionization is plasma ionization, and the temperature of the plasma ionization is 1600-1800°C, for example, it can be 1600°C, 1623°C, 1645°C, 1667°C, 1689°C, 1712°C, 1734°C, 1756°C, 1778°C or 1800°C, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0042] Preferably, the temperature of the decomposition gas is 1250-1350°C, for example, it can be 1250°C, 1262°C, 1273°C, 1284°C, 1295°C, 1306°C, 1317°C, 1328°C, 1339°C or 1350°C, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0043] Preferably, the temperatures of the air in step (2) and the air in step (4) are each independently room temperature.

[0044] The room temperature mentioned in the present invention refers to the ambient temperature without cooling or heating, which may range from -20 to 40°C, generally around 20 to 30°C.

[0045] Preferably, the temperature of the first mixed gas is 680-750°C, for example, it can be 680°C, 688°C, 696°C, 704°C, 712°C, 719°C, 727°C, 735°C, 743°C or 750°C, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0046] Preferably, the temperature of the second cooling gas is 130-210°C, for example, it can be 130°C, 139°C, 148°C, 157°C, 166°C, 175°C, 184°C, 193°C, 202°C or 210°C, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0047] Preferably, the temperature of the third cooling gas is 40-55°C, for example, it can be 40°C, 42°C, 44°C, 45°C, 47°C, 49°C, 50°C, 52°C, 54°C or 55°C, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0048] Preferably, the temperature of the fourth mixed gas is 30-40°C, for example, it can be 30°C, 32°C, 33°C, 34°C, 35°C, 36°C, 37°C, 38°C, 39°C or 40°C, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0049] The utility model further preferably controls the temperature of the gas after each cooling step within the above range, which can not only match the appropriate equipment size, but also achieve the purpose of balancing the air volume and the circulating cooling heat exchange area, and ultimately can accurately control the target emission temperature.

[0050] Preferably, the temperature of the purified gas is ≤25°C, for example, it may be 25°C, 24°C, 23°C, 22°C, 21°C or 20°C, etc., but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0051] Preferably, condensate is generated during the third cooling process, and the condensate is discharged into a collection unit under the action of gravity to be collected and discharged.

[0052] It is worth noting that the circulating cooling medium of the present invention is circulating cooling water. Generally speaking, the temperature of the circulating cooling water is 20±2°C.

[0053] Compared with the prior art, the utility model has at least the following beneficial effects:

[0054] (1) The plasma exhaust gas treatment device provided by the utility model cools the exhaust gas after ionization of the semiconductor exhaust gas by arranging air cooling and circulating cooling medium alternating cooling, wherein water is only used as a circulating cooling medium and can be recycled, and does not involve mixing and contact between water and exhaust gas, effectively avoiding the waste of a large amount of water resources and the generation of acidic wastewater;

[0055] (2) The water-free ionization treatment method for semiconductor exhaust gas provided by the utility model can realize cooling of the ionized gas within a reasonable equipment space by reasonably designing each cooling section and optimally setting the temperature of each cooling section, so that it reaches the target emission temperature, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 It is a structural diagram of the plasma waste gas treatment device provided by the utility model.

[0057] Figure 2-Figure 3 It is a structural diagram of a plasma torch part in a plasma waste gas treatment device provided by the utility model.

[0058] Figure 4 It is a structural diagram of the gas intake part in the plasma waste gas treatment device provided by the utility model.

[0059] Figure 5 It is a structural diagram of a reaction air injection portion in a plasma waste gas treatment device provided by the utility model.

[0060] Figure 6 It is a structural diagram of the reaction part in the plasma waste gas treatment device provided by the utility model.

[0061] Figure 7 It is a structural diagram of the first circulating medium cooling part in the plasma waste gas treatment device provided by the utility model.

[0062] Figure 8 It is a structural diagram of a collecting unit in a plasma waste gas treatment device provided by the utility model.

[0063] Fig. 9 It is a structural diagram of the liquid phase discharge part in the plasma waste gas treatment device provided by the utility model.

[0064] Fig.10 It is a structural diagram of the electronic cooling part in the plasma waste gas treatment device provided by the utility model.

[0065] In the figure, 1, plasma torch part; 1-1, cooling water injection port; 1-2, cooling water discharge port; 1-2, circulating cooling medium discharge port of plasma torch part; 1-3, nitrogen injection port; 1-4, cathode wiring hole; 1-5, anode wiring hole; 2, gas suction part; 2-1, conical structure; 2-2, circulating cooling medium injection port of gas suction part; 2-3, circulating cooling medium discharge port of gas suction part; 3, reaction air injection part; 3-1, inner wall layer; 3-2, outer shell layer; 3-3, air delivery port; 4, reaction part; 4-1, reaction chamber; 4-2, circulating cooling chamber; 4-3, circulating cooling medium injection port of reaction part; 4-4, circulating cooling medium discharge port of reaction part; 5, first air cooling part; 6, first circulating medium cooling part; 6-1, shell and tube structure; 6-2, first Circulating cooling medium injection port of the circulating medium cooling section; 6-3, circulating cooling medium discharge port of the first circulating medium cooling section; 7, collecting unit; 7-1, air inlet of the collecting unit; 7-2, air outlet of the collecting unit; 7-3, air injection port; 7-4, circulating cooling medium injection port of the collecting unit; 7-5, circulating cooling medium discharge port of the collecting unit; 7-6, temperature sensor; 8, liquid phase discharge section; 8-1, liquid level sensor; 8-2, liquid phase pipeline mounting piece; 8-3, liquid phase discharge port; 9, second circulating medium cooling section; 10, second air cooling section; 11, electronic cooling section; 11-1, air inlet of the electronic cooling section; 11-2, air outlet of the electronic cooling section; 11-3, circulating cooling medium inlet of the electronic cooling section; 11-4, circulating cooling medium outlet of the electronic cooling section. DETAILED DESCRIPTION

[0066] To facilitate understanding of the present invention, the present invention is listed in the following embodiments. Those skilled in the art should understand that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0067] It should be understood that, in the description of the present utility model, the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, which is only for the convenience of describing the present utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present utility model, unless otherwise specified, "multiple" means two or more.

[0068] It should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "disposed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0069] Those skilled in the art should understand that the utility model must include necessary pipelines, conventional valves and general pump equipment for realizing a complete process, but the above content does not belong to the main utility model points of the utility model. Those skilled in the art can add layouts on their own based on the process flow and equipment structure selection, and the utility model does not make special requirements and specific limitations on this.

[0070] Example 1

[0071] This embodiment provides a plasma waste gas treatment device, referring to Figure 1 The plasma waste gas treatment device includes: a first unit, a collecting unit 7 and a second unit in sequence along the waste gas conveying direction. The first unit and the second unit are arranged in parallel on the collecting unit 7, and the internal spaces of the first unit, the collecting unit 7 and the second unit are connected.

[0072] The first unit includes a plasma torch part 1, a gas suction part 2, a reaction air injection part 3, a reaction part 4, a first air cooling part 5 and a first circulating medium cooling part 6 in sequence along the exhaust gas conveying direction; the gas channel of the first circulating medium cooling part 6 is connected to the collecting unit 7.

[0073] Reference Figure 2-Figure 3 The plasma torch part 1 is arranged on the upper part of the gas suction part 2; the plasma torch part 1 includes a cooling water injection port 1-1, a cooling water discharge port 1-2, a nitrogen injection port 1-3, a cathode wiring hole 1-4 and an anode wiring hole 1-5, the cooling water injection port 1-1 and the cooling water discharge port 1-2 are connected, and the cathode wiring hole 1-4 and the anode wiring hole 1-5 are used for arranging the cathode and the anode, respectively.

[0074] See also Figure 4 , along the axial direction from top to bottom, the diameter of the gas suction part 2 gradually decreases, specifically presenting a conical structure 2-1; a flange is provided at the lower part of the gas suction part 2, and a circulating cooling medium injection port 2-2 of the gas suction part and a circulating cooling medium discharge port 2-3 of the gas suction part are provided on the flange; the circulating cooling medium injection port 2-2 of the gas suction part and the circulating cooling medium discharge port 2-3 of the gas suction part are connected and are used to transport the circulating cooling medium.

[0075] See also Figure 5 The reaction air injection part 3 includes an outer shell layer 3-2 and an inner wall layer 3-1. The inner wall layer 3-1 of the reaction air injection part 3 is provided with holes connected to the air delivery port 3-3 and evenly distributed.

[0076] See also Figure 6 The reaction part 4 includes a reaction chamber 4-1 and a circulating cooling chamber 4-2 in sequence from the inside to the outside in the radial direction; a circulating cooling medium is arranged in the circulating cooling chamber 4-2, and a circulating cooling medium injection port 4-3 of the reaction part and a circulating cooling medium discharge port 4-4 of the reaction part are arranged on the circulating cooling chamber 4-2; the circulating cooling medium injection port 4-3 of the reaction part and the circulating cooling medium discharge port 4-4 of the reaction part are connected and used for conveying the circulating cooling medium.

[0077] The first air-cooling part 5 includes an outer shell layer 3 - 2 and an inner wall layer 3 - 1 . The inner wall layer 3 - 1 of the first air-cooling part 5 is provided with holes connected to the air delivery port 3 - 3 and evenly distributed.

[0078] See also Figure 7The first circulating medium cooling part 6 includes a tube shell structure 6-1, and the tube shell structure 6-1 includes a gas channel cavity and a circulating cooling medium cavity in sequence from the inside to the outside in the radial direction. The circulating cooling medium cavity in the first circulating medium cooling part 6 is used to pass the circulating cooling medium to exchange heat with the treated gas, and the circulating cooling medium injection port 6-2 of the first circulating medium cooling part and the circulating cooling medium discharge port 6-3 of the first circulating medium cooling part are provided on the circulating cooling cavity 4-2, and the circulating cooling medium injection port 6-2 of the first circulating medium cooling part and the circulating cooling medium discharge port 6-3 of the first circulating medium cooling part are connected.

[0079] The second unit includes a second circulating medium cooling part 9 , a second air cooling part 10 and an electronic cooling part 11 in sequence along the exhaust gas conveying direction, and a gas channel of the second circulating medium cooling part 9 is connected to the collecting unit 7 .

[0080] The second circulating medium cooling part 9 includes a gas channel cavity and a circulating cooling medium cavity in sequence from the inside to the outside in the radial direction; wherein, the circulating cooling medium cavity in the first circulating medium cooling part 6 and the second circulating medium cooling is used to pass the circulating cooling medium and exchange heat with the treated gas, and the circulating cooling cavity is provided with a circulating cooling medium injection port and a circulating cooling medium discharge port, and the circulating cooling medium injection port and the circulating cooling medium discharge port are connected.

[0081] The second air cooling part 10 includes an outer shell layer and an inner wall layer. The inner wall layer of the second air cooling part 10 is provided with holes connected to the air delivery port and evenly distributed.

[0082] See also Fig.10 The electronic cooling unit 11 includes a thermoelectric element for gas phase cooling; at least two thermoelectric elements are provided; the electronic cooling unit 11 includes an air inlet 11-1 of the electronic cooling unit, an air outlet 11-2 of the electronic cooling unit, a circulating cooling medium inlet 11-3 of the electronic cooling unit and a circulating cooling medium outlet 11-4 of the electronic cooling unit, and the circulating cooling medium inlet 11-3 of the electronic cooling unit and the circulating cooling medium outlet 11-4 of the electronic cooling unit are used to pass the circulating cooling medium.

[0083] See also Figure 8The collecting unit 7 comprises an air inlet 7-1 of the collecting unit, an air outlet 7-2 of the collecting unit, an air injection port 7-3, a circulating cooling medium injection port, a circulating cooling medium discharge port and a circulating cooling medium cavity; the air inlet 7-1 is connected to the first circulating medium cooling part 6 in the first unit, and the air outlet 7-2 is connected to the second circulating medium cooling part 9 in the second unit; the air injection port 7-3 is arranged around the collecting unit 7, and the cooling medium injection port and the circulating cooling medium discharge port in the collecting unit 7 are arranged on the circulating cooling medium cavity; the circulating cooling medium cavity is arranged at the upper position of the collecting unit 7; a temperature sensor 7-6 is arranged in the upper inner part of the circulating cooling medium cavity.

[0084] See also Fig. 9 The plasma waste gas treatment device further comprises a liquid phase discharge part 8 arranged at the bottom of the collecting unit 7; a liquid level sensor 8-1 is arranged on the liquid phase discharge part 8; a liquid phase pipeline installation part 8-2 and a liquid phase discharge port 8-3 are also arranged on the liquid phase discharge part 8; a transparent pipeline is arranged on the liquid phase pipeline installation part 8-2; the transparent pipeline is used to observe the liquid level with naked eyes. The liquid phase discharge port 8-3 is connected to the liquid phase conveying device.

[0085] Comparative Example 1

[0086] This comparative example provides a plasma exhaust gas treatment device, which is the same as Example 1 except that the first air cooling part and the second air cooling part are replaced by the first water cooling part and the second water cooling part.

[0087] Specifically, the first air cooling part includes an outer shell layer and an inner wall layer, and the inner wall layer of the first air cooling part is provided with holes connected to the water conveying device and evenly distributed. The second air cooling part includes an outer shell layer and an inner wall layer, and the inner wall layer of the second air cooling part is provided with holes connected to the water conveying device and evenly distributed.

[0088] Comparative Example 2

[0089] This comparative example provides a plasma exhaust gas treatment device, which is the same as Example 1 except that the second air cooling part is replaced by a third circulating medium cooling part.

[0090] Comparative Example 3

[0091] This comparative example provides a plasma exhaust gas treatment device, which is the same as Example 1 except that the electronic cooling part is not provided.

[0092] Comparative Example 4

[0093] This comparative example provides a plasma exhaust gas treatment device, which is the same as Example 1 except that the first air cooling part is replaced by a circulating medium cooling part.

[0094] Application Example 1

[0095] This application example provides a method for anhydrous ionization treatment of semiconductor tail gas, which is performed using the plasma waste gas treatment device provided in Example 1, and specifically includes the following steps:

[0096] (1) Semiconductor tail gas at a temperature of 20° C. is ionized by a plasma at 1600° C. to produce a decomposition gas at 1300° C.; the reactions occurring during the plasma ionization process include: C3H8+5O2→3CO2+4H2O, SiH4+2O2→SiO2+2H2O, 2H2+O2→2H2O;

[0097] (2) The decomposed gas is mixed with air and subjected to a first cooling process to obtain a first mixed gas having a temperature of 700° C.;

[0098] (3) The first mixed gas is subjected to a second cooling by a first circulating cooling medium to obtain a second cooling gas having a temperature of 200° C., and the second cooling gas is subjected to a third cooling by a second circulating cooling medium to obtain a third cooling gas having a temperature of 50° C., wherein condensate is generated during the third cooling process, and the condensate is discharged into a collection unit under the action of gravity for collection and external discharge;

[0099] (4) The third cooling gas is mixed with air to perform a fourth cooling process to obtain a fourth mixed gas with a temperature of 35° C.;

[0100] (5) The fourth mixed gas is subjected to fifth cooling by an electronic cooling unit to obtain a purified gas having a temperature of ≤25°C.

[0101] This application example adopts air cooling, first cycle cooling with cooling medium, second cycle cooling with cooling medium, air cooling and thermoelectric element cooling in sequence, which has the following advantages: 1. The tail gas does not need to come into contact with water, thus avoiding a large amount of water resource waste; 2. Since no water is used, the acidic gas in the tail gas will not form a large amount of acidic waste liquid; 3. The temperature and cooling capacity in each cooling step are reasonably distributed, and efficient cooling of high-temperature tail gas can be achieved within a reasonable equipment space; 4. Before the electronic cooling unit is cooled, air cooling is used to fine-tune the temperature. The temperature regulation has a high sensitivity and can protect the electronic devices in the electronic cooling unit.

[0102] Application Example 2

[0103] This application example provides a method for anhydrous ionization treatment of semiconductor tail gas, which is performed using the plasma waste gas treatment device provided in Example 1, and specifically includes the following steps:

[0104] (1) Semiconductor tail gas with a temperature of 15°C is ionized by a plasma at 1800°C to produce decomposition gas at 1250°C;

[0105] (2) The decomposed gas is mixed with air and subjected to a first cooling process to obtain a first mixed gas having a temperature of 750° C.;

[0106] (3) The first mixed gas is subjected to a second cooling by a first circulating cooling medium to obtain a second cooling gas having a temperature of 210° C., and the second cooling gas is subjected to a third cooling by a second circulating cooling medium to obtain a third cooling gas having a temperature of 55° C., wherein condensate is generated during the third cooling process, and the condensate is discharged into a collection unit under the action of gravity for collection and external discharge;

[0107] (4) the third cooling gas is mixed with air to perform a fourth cooling to obtain a fourth mixed gas with a temperature of 30° C.;

[0108] (5) The fourth mixed gas is subjected to fifth cooling by an electronic cooling unit to obtain a purified gas having a temperature of ≤25°C.

[0109] This application example adopts air cooling, first cycle cooling with cooling medium, second cycle cooling with cooling medium, air cooling and thermoelectric element cooling in sequence, which has the following advantages: 1. The tail gas does not need to come into contact with water, thus avoiding a large amount of water resource waste; 2. Since no water is used, the acidic gas in the tail gas will not form a large amount of acidic waste liquid; 3. The temperature and cooling capacity in each cooling step are reasonably distributed, and efficient cooling of high-temperature tail gas can be achieved within a reasonable equipment space; 4. Before the electronic cooling unit is cooled, air cooling is used to fine-tune the temperature. The temperature regulation has a high sensitivity and can protect the electronic devices in the electronic cooling unit.

[0110] Application Example 3

[0111] This application example provides a method for anhydrous ionization treatment of semiconductor tail gas, which is performed using the plasma waste gas treatment device provided in Example 1, and specifically includes the following steps:

[0112] (1) Semiconductor tail gas with a temperature of 25°C is ionized by a plasma at 1600°C to produce decomposition gas at 1350°C;

[0113] (2) the decomposed gas is mixed with air and subjected to a first cooling process to obtain a first mixed gas having a temperature of 680° C.;

[0114] (3) The first mixed gas is subjected to a second cooling by a first circulating cooling medium to obtain a second cooled gas having a temperature of 130° C., and the second cooled gas is subjected to a third cooling by a second circulating cooling medium to obtain a third cooled gas having a temperature of 43° C., wherein condensate is generated during the third cooling process, and the condensate is discharged into a collection unit under the action of gravity for collection and external discharge;

[0115] (4) The third cooling gas is mixed with air to perform a fourth cooling process to obtain a fourth mixed gas with a temperature of 40° C.;

[0116] (5) The fourth mixed gas is subjected to fifth cooling by an electronic cooling unit to obtain a purified gas having a temperature of ≤25°C.

[0117] This application example adopts air cooling, first cycle cooling with cooling medium, second cycle cooling with cooling medium, air cooling and thermoelectric element cooling in sequence, which has the following advantages: 1. The tail gas does not need to come into contact with water, thus avoiding a large amount of water resource waste; 2. Since no water is used, the acidic gas in the tail gas will not form a large amount of acidic waste liquid; 3. The temperature and cooling capacity in each cooling step are reasonably distributed, and efficient cooling of high-temperature tail gas can be achieved within a reasonable equipment space; 4. Before the electronic cooling unit is cooled, air cooling is used to fine-tune the temperature. The temperature regulation has a high sensitivity and can protect the electronic devices in the electronic cooling unit.

[0118] Application Comparative Examples 1 to 4

[0119] Application Examples 1 to 4 are basically the same as Application Example 1 except that the plasma waste gas treatment devices of Comparative Examples 1 to 4 are used.

[0120] The application of Comparative Example 1 will generate a large amount of waste water, and the acidic substances will be highly corrosive after being dissolved in water, causing serious corrosion of the equipment.

[0121] In the comparative example 2, the heat exchange area of ​​the third circulating medium cooling part is insufficient, and the required temperature of the electronic cooling part cannot be reached, resulting in a shortened service life of the electronic cooling part.

[0122] In the comparative example 3, no electronic cooling unit is provided, resulting in that the final exhaust gas temperature is difficult to meet the standard.

[0123] In Comparative Example 4, circulating medium is directly used to cool the tail gas after plasma treatment, but there is insufficient heat exchange area and a large temperature difference on both sides of the material, which significantly shortens the life of the equipment.

[0124] In summary, the plasma waste gas treatment device and the water-free ionization treatment method of semiconductor exhaust provided by the utility model can avoid the problem of large amount of water waste caused by the mixing and cooling of the decomposed gas after plasma ionization and water, as well as the generation of waste acid liquid by designing an alternating cooling method of air cooling and circulating cooling medium.

[0125] The utility model uses the above embodiments to illustrate the detailed features of the utility model, but the utility model is not limited to the above detailed features, that is, it does not mean that the utility model must rely on the above detailed features to be implemented. Those skilled in the art should understand that any improvement to the utility model, equivalent replacement of the technical features selected by the utility model, addition of auxiliary technical features, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the utility model.

Claims

1. A plasma waste gas treatment device, characterized in that: The plasma waste gas treatment device comprises, in sequence along the waste gas conveying direction: a first unit, a collecting unit and a second unit, wherein the first unit and the second unit are arranged in parallel on the collecting unit, and the internal spaces of the first unit, the collecting unit and the second unit are connected; The first unit includes a plasma torch section, a gas suction section, a reaction air injection section, a reaction section, a first air cooling section and a first circulating medium cooling section in sequence along the exhaust gas conveying direction; The gas channel of the first circulating medium cooling part is connected to the collecting unit; The second unit includes a second circulating medium cooling part, a second air cooling part and an electronic cooling part in sequence along the exhaust gas conveying direction, and a gas channel of the second circulating medium cooling part is connected to the collecting unit.

2. The plasma exhaust gas treatment device according to claim 1, characterized in that: The plasma torch part is arranged on the upper part of the gas suction part; The plasma torch part includes a cooling water injection port, a cooling water discharge port, a nitrogen injection port, a cathode wiring hole and an anode wiring hole. The cooling water injection port and the cooling water discharge port are connected. The cathode wiring hole and the anode wiring hole are used to arrange the cathode and the anode respectively.

3. The plasma exhaust gas treatment device according to claim 1, characterized in that: The diameter of the gas suction portion gradually decreases along the axial direction from top to bottom.

4. The plasma exhaust gas treatment device according to claim 1, characterized in that: The reaction air injection part comprises an outer shell layer and an inner wall layer. The inner wall layer of the reaction air injection part is provided with holes connected to the air delivery port and evenly distributed.

5. The plasma exhaust gas treatment device according to claim 1, characterized in that: The first air cooling part comprises an outer shell layer and an inner wall layer, and the inner wall layer of the first air cooling part is provided with holes connected to the air delivery port and evenly distributed.

6. The plasma exhaust gas treatment device according to claim 1, characterized in that: The first circulating medium cooling part includes a gas channel cavity and a circulating cooling medium cavity in sequence from inside to outside along the radial direction; the second circulating medium cooling part includes a gas channel cavity and a circulating cooling medium cavity in sequence from inside to outside along the radial direction.

7. The plasma exhaust gas treatment device according to claim 1, characterized in that: The second air cooling part comprises an outer shell layer and an inner wall layer, and the inner wall layer of the second air cooling part is provided with holes connected to the air delivery port and evenly distributed.

8. The plasma exhaust gas treatment device according to claim 1, characterized in that: The collecting unit comprises an air inlet, an air outlet, an air injection port, a circulating cooling medium injection port, a circulating cooling medium discharge port and a circulating cooling medium cavity; the air inlet is connected to the first circulating medium cooling part in the first unit, and the air outlet is connected to the second circulating medium cooling part in the second unit; the air injection port is arranged around the collecting unit, and the cooling medium injection port and the circulating cooling medium discharge port in the collecting unit are arranged on the circulating cooling medium cavity.

9. The plasma exhaust gas treatment device according to claim 1, characterized in that: The plasma waste gas treatment device further comprises a liquid phase discharge portion arranged at the bottom of the collecting unit; a liquid level sensor is arranged on the liquid phase discharge portion.

10. The plasma exhaust gas treatment device according to claim 1, characterized in that: The electronic cooling unit includes a thermoelectric element for gas phase cooling; at least two thermoelectric elements are provided; and the electronic cooling unit includes an air inlet, an air outlet, a circulating cooling medium inlet, and a circulating cooling medium outlet.

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