Waste gas combustion furnace for semiconductor production

Abstract

The invention discloses a waste gas combustion furnace for semiconductor production, which belongs to the technical field of semiconductor waste gas treatment, and comprises a furnace body, a combustion chamber arranged in a cavity of the furnace body, and a combustion chamber arranged in the cavity of the furnace body, the combustion engine is arranged in the combustion chamber and used for providing heat for the combustion chamber; the heat exchanger is arranged in the cavity of the furnace body, and the heat exchanger is provided with a cold side channel and a hot side channel; the waste gas inlet is formed in the furnace body and communicated with a cold side channel inlet of the heat exchanger; the waste gas outlet is formed in the furnace body and is communicated with a hot side channel outlet of the heat exchanger; a cold side channel outlet of the heat exchanger communicates with the air inlet side of the combustion chamber, and a hot side channel inlet of the heat exchanger communicates with the air outlet side of the combustion chamber. The waste heat utilization rate of the waste gas combustion furnace is increased, and the fuel consumption and the operation cost are reduced.

Description

Technical Field

[0001] This invention relates to the field of semiconductor waste gas treatment technology, and in particular to a waste gas combustion furnace for semiconductor production. Background Technology

[0002] Conductor manufacturing processes (such as etching, deposition, epitaxy, cleaning, etc.) generate a large amount of process waste gas containing harmful components such as silane, perfluorinated carbon, and organic solvent vapors. This type of waste gas is characterized by toxicity, flammability, and strong greenhouse effect, and must be strictly treated before it can be discharged. At present, combustion waste gas treatment equipment has become the mainstream equipment for waste gas treatment in the semiconductor industry due to its high treatment efficiency and wide applicability.

[0003] Existing combustion-type waste gas treatment equipment typically includes a combustion chamber, waste gas inlet, fuel supply system, and exhaust pipe. Its working process is as follows: process waste gas is introduced into the equipment from the production machine, and in the combustion chamber, it works together with fuel (such as natural gas or liquefied petroleum gas) or electric heating elements to thermally oxidize and decompose harmful gases at high temperatures (usually 700℃-1200℃), generating carbon dioxide, water, and acidic gases, which are then discharged after subsequent washing treatment.

[0004] However, existing equipment has the following technical problems in practical applications: low waste heat utilization rate and high operating costs. There is a lack of effective heat exchange structure between the combustion chamber and the exhaust gas inlet of the existing equipment. The ambient temperature exhaust gas directly enters the combustion chamber, requiring a large amount of fuel or electricity to heat it to the decomposition temperature. At the same time, the high temperature exhaust gas (which can reach over 800°C) generated by combustion carries a large amount of heat and is directly discharged into the subsequent scrubbing system or flue. The heat is not recovered and utilized, resulting in significant energy waste. For semiconductor production lines that operate continuously for a long time, this inefficient energy consumption mode leads to high equipment operating costs and increases the production cost burden of enterprises.

[0005] In response to the aforementioned technologies, there is an urgent need to design and develop a waste gas combustion furnace for semiconductor production that can improve the waste heat utilization rate of the waste gas combustion furnace and reduce fuel consumption and operating costs. Summary of the Invention

[0006] In order to improve the waste heat utilization rate of the waste gas combustion furnace and reduce fuel consumption and operating costs, this application provides a waste gas combustion furnace for semiconductor production.

[0007] The technical solution of the waste gas combustion furnace for semiconductor manufacturing provided in this application is as follows: A waste gas combustion furnace for semiconductor manufacturing includes a furnace body and further includes: The combustion chamber is located within the cavity of the furnace body; A burner, disposed within the combustion chamber, is used to provide heat to the combustion chamber; A heat exchanger is disposed within the cavity of the furnace body, and the heat exchanger has a cold-side passage and a hot-side passage; The exhaust gas inlet is located on the furnace body and is connected to the cold side channel inlet of the heat exchanger; The exhaust gas outlet is located on the furnace body and is connected to the hot-side channel outlet of the heat exchanger. The cold-side passage outlet of the heat exchanger is connected to the air intake side of the combustion chamber, and the hot-side passage inlet of the heat exchanger is connected to the air outlet side of the combustion chamber.

[0008] By adopting the above technical solution, the combustion chamber is located inside the furnace body, the burner is located inside the combustion chamber, the heat exchanger is located inside the furnace body, the exhaust gas inlet is located on the furnace body and connected to the cold side channel inlet of the heat exchanger, and the exhaust gas outlet is located on the furnace body and connected to the hot side channel outlet of the heat exchanger; the cold side channel outlet of the heat exchanger is connected to the air inlet side of the combustion chamber, and the hot side channel inlet of the heat exchanger is connected to the air outlet side of the combustion chamber. When using this device for waste gas treatment, the waste gas to be treated enters the cold side channel of the heat exchanger through the waste gas inlet. At this time, the waste gas to be treated exchanges heat with the high-temperature waste gas flowing through the hot side channel in the heat exchanger, absorbs heat and rises to the preset preheating temperature. The heated waste gas to be treated enters the air inlet side of the combustion chamber through the cold side channel outlet of the heat exchanger. The burner provides heat to the combustion chamber, so that the inside of the combustion chamber is maintained at the preset high-temperature decomposition temperature. The waste gas to be treated is fully combusted and decomposed in the combustion chamber, and transformed into harmless or low-harm substances. The high-temperature waste gas generated by combustion is discharged from the outlet side of the combustion chamber and enters the hot side channel of the heat exchanger through the inlet of the hot side channel. During the flow through the hot side channel, the high-temperature waste gas exchanges heat with the waste gas to be treated in the cold side channel and releases heat to cool down. The cooled waste gas is discharged through the hot side channel outlet and the waste gas outlet of the heat exchanger. This device uses the high-temperature exhaust gas generated by combustion to preheat the exhaust gas to be treated before it enters the combustion chamber, which significantly increases the initial temperature of the exhaust gas to be treated. This reduces the auxiliary fuel consumption required to maintain the high temperature of the combustion chamber, realizes the cascade utilization of waste heat, and effectively solves the technical problems of low waste heat utilization rate and high operating cost in the existing technology.

[0009] Preferably, the furnace body is further provided with an acid mist collection mechanism, which includes a collection box, a conduit connected at one end to the exhaust gas outlet, several baffles arranged alternately in the collection box, a gas collection pipe provided in the collection box, and a drain pipe connected at one end to the waste liquid treatment system. A liquid collection tank is provided in the collection box, the other end of the drain pipe is connected to the liquid collection tank, the other end of the conduit extends into the collection box, and the gas collection pipe is connected to the external exhaust duct.

[0010] By adopting the above technical solution, several baffles are staggered in the collection box, one end of the duct is connected to the exhaust gas outlet, the other end of the duct extends into the collection box, the gas collection pipe is set in the collection box and connected to the external exhaust pipe, a liquid collection tank is set in the collection box, one end of the liquid discharge pipe is connected to the waste liquid treatment system, and the other end of the liquid discharge pipe is connected to the liquid collection tank. During the waste gas treatment process using this device, the waste gas cooled by the heat exchanger is discharged from the waste gas outlet and enters the collection box through the duct. The waste gas first enters the lower space of the collection box; then, the waste gas flows upward in the collection box and flows through several staggered baffles in sequence. During the flow through the baffles, the flow direction of the waste gas changes continuously. The acid mist particles carried in the waste gas collide with the surface of the baffles due to inertia and condense into droplets. The condensed droplets flow downwards along the surface of the baffle plate under the action of gravity, and finally drip into the liquid collection tank at the bottom of the collection box. The acidic liquid collected in the liquid collection tank is discharged to the waste liquid treatment system through the drain pipe. The purified exhaust gas after the acid mist is removed continues to flow upwards and enters the external exhaust pipe through the gas collection pipe in the collection box, and is finally discharged into the subsequent treatment system or discharged in compliance with standards. This effectively avoids acid mist from entering the downstream fan and exhaust pipe, significantly reduces the risk of corrosion inside the equipment and pipelines, and solves the problem of secondary corrosion caused by acidic aerosols in the existing technology.

[0011] Preferably, the bottom of the liquid collection tank has an inclined structure that gradually tapers towards the drain pipe, and the inner wall of the liquid collection tank is provided with a plurality of protrusions, which are arranged in an array to increase the residence time of gas in the liquid collection tank.

[0012] By adopting the above technical solution, the bottom of the liquid collection tank is an inclined structure that gradually converges towards the drain pipe. Several protrusions are provided on the inner wall of the liquid collection tank. The protrusions are arranged in an array, so that the acidic liquid dripping from the baffle plate will automatically collect along the inclined structure to the drain pipe under the action of gravity, thus avoiding the accumulation and residue of liquid at the bottom of the liquid collection tank. Meanwhile, when the exhaust gas enters the bottom of the collection box and flows over the liquid collection tank, the array of protrusions increases the contact area between the exhaust gas and the inner wall of the liquid collection tank, and generates local turbulence on the airflow, thereby increasing the residence time of the gas in the liquid collection tank area. This allows the acid mist particles entrained in the exhaust gas to have more time to settle or adhere to the surface of the protrusions and condense and drip down, further improving the acid mist collection efficiency.

[0013] Preferably, the inner wall of the heat-side channel of the heat exchanger and the inner wall of the exhaust gas outlet are provided with a corrosion-resistant coating. The corrosion-resistant coating is a multi-layer composite structure, which includes, from the inside to the outside, a ceramic bottom layer, a nickel-based alloy intermediate layer and a polytetrafluoroethylene top layer.

[0014] By adopting the above technical solution, the inner wall of the heat-side channel and the inner wall of the exhaust gas outlet of the heat exchanger are provided with a corrosion-resistant coating. The corrosion-resistant coating is a multi-layer composite structure, which includes, from the inside to the outside: a ceramic bottom layer, a nickel-based alloy intermediate layer and a polytetrafluoroethylene top layer. Among them, the ceramic bottom layer is directly attached to the surface of the metal substrate and has excellent thermal stability and chemical inertness. It can effectively prevent acidic gases in high-temperature exhaust gas from directly contacting the metal substrate, and at the same time act as a thermal barrier to reduce the temperature fluctuation of the substrate surface. The nickel-based alloy intermediate layer is positioned between the ceramic substrate and the polytetrafluoroethylene (PTFE) top layer. On one hand, it serves as a transition layer to enhance the adhesion between the coating and the substrate. On the other hand, it has excellent corrosion resistance and can form a second protective barrier in the intermediate layer. The PTFE top layer, as the outermost layer, has excellent chemical corrosion resistance, hydrophobicity, and a low coefficient of friction. It can effectively resist the erosion of strong acidic media such as hydrofluoric acid and hydrochloric acid. At the same time, its hydrophobic properties make it difficult for condensate droplets to adhere to the coating surface, reducing the contact time between droplets and the coating, and further reducing the risk of corrosion.

[0015] Preferably, the furnace body is further provided with a rapid cooling and conditioning mechanism, which includes a cavity component, a plurality of atomizing nozzles disposed within the cavity component, a water supply pipeline connected to the atomizing nozzles, an alkaline storage tank for storing alkaline neutralizing solution, a metering pump disposed between the alkaline storage tank and the water supply pipeline, a control circuit board, and a pH sensor disposed within the cavity component. The cavity component has an air inlet and an air outlet. The air inlet is connected to the air outlet side of the combustion chamber, and the air outlet is connected to the hot side channel inlet of the heat exchanger. The plurality of atomizing nozzles are used to spray cooling water into the cavity component. The metering pump is used to inject the alkaline neutralizing solution from the alkaline storage tank into the water supply pipeline. The control circuit board is electrically connected to the pH sensor and the metering pump respectively. The control circuit board is configured to control the start / stop and flow rate of the metering pump according to the pH signal fed back by the pH sensor.

[0016] By adopting the above technical solution, the cavity component has an air inlet and an air outlet. The air inlet is connected to the air outlet side of the combustion chamber, and the air outlet is connected to the inlet of the hot side channel of the heat exchanger. A pH sensor is installed inside the cavity component, and several atomizing nozzles are installed inside the cavity component. A water supply pipeline is connected to the atomizing nozzles. An alkaline solution storage tank stores alkaline neutralizing solution. A metering pump is installed between the alkaline solution storage tank and the water supply pipeline. The control circuit board is electrically connected to the pH sensor and the metering pump, respectively. During the waste gas treatment process using this device, the waste gas, after high-temperature combustion and decomposition in the combustion chamber, is discharged from the outlet side of the combustion chamber and enters the cavity through the inlet. The pH sensor monitors the pH value of the condensate in the cavity in real time and sends the pH signal to the control circuit board. The control circuit board compares the received pH signal with the preset pH threshold. When the pH signal is lower than the preset threshold (e.g., pH < 7), the control circuit board controls the metering pump to start, injecting the alkaline neutralizing solution from the alkaline storage tank into the water supply pipeline in a metered manner. After mixing with the cooling water, the solution is sprayed into the cavity through several atomizing nozzles. When the pH signal returns to the preset threshold range, the control circuit board controls the metering pump to stop. During the process of spraying a mixture of cooling water and alkaline neutralizing liquid into the cavity from the atomizing nozzle, the mixture comes into direct contact with the high-temperature exhaust gas. On the one hand, the exhaust gas temperature is rapidly reduced by absorbing heat through the evaporation of water, bringing the exhaust gas temperature down to a range that subsequent equipment can withstand (such as 200℃-300℃). On the other hand, the alkaline neutralizing liquid in the mixture reacts with the acidic gases (such as hydrofluoric acid, hydrochloric acid, etc.) in the exhaust gas to generate neutral salts, thus inhibiting the presence of acidic gases at the source. After cooling and neutralization, the exhaust gas is discharged from the outlet and enters the hot side channel of the heat exchanger for subsequent waste heat recovery. The condensate generated by the spraying and the salts generated by the neutralization reaction are collected at the bottom of the cavity and discharged to the waste liquid treatment system through the drain port. This effectively solves the equipment corrosion problem caused by acidic gases and acid mist in the existing technology, and significantly improves the operational stability and service life of the equipment.

[0017] Preferably, the combustion chamber is provided with a heat storage body for absorbing and storing combustion heat. The heat storage body is located downstream of the flame injection direction of the burner, and the heat storage body is a honeycomb ceramic structure or a metal wire mesh structure.

[0018] By adopting the above technical solution, a heat storage body for absorbing and storing combustion heat is provided in the combustion chamber. The heat storage body is located downstream of the flame injection direction of the burner. The heat storage body is a honeycomb ceramic structure or a metal wire mesh structure. During the waste gas treatment process using this device, the high-temperature flame generated by the burner heats the heat storage body to a high temperature. When the waste gas to be treated enters the combustion chamber, it is first heated in the flame area and then heated a second time when it flows through the heat storage body. This allows the waste gas temperature to reach the decomposition temperature of difficult-to-decompose gases such as perfluorocarbons more quickly. At the same time, the heat storage body acts as a heat buffer medium, maintaining a stable furnace temperature when the flame fluctuates or the waste gas flow changes. This significantly improves the decomposition efficiency of perfluorocarbons and reduces greenhouse gas emissions, while effectively reducing auxiliary fuel consumption, achieving the dual effects of energy saving and high-efficiency purification.

[0019] Preferably, the combustion chamber is provided with a plurality of guide ribs for extending the flow path of exhaust gas in the combustion chamber. The plurality of guide ribs are disposed on the inner wall of the combustion chamber and located downstream of the heat storage body. The guide ribs are arranged spirally or staggered along the airflow direction.

[0020] By adopting the above technical solution, several guide ribs are set on the inner wall of the combustion chamber and located downstream of the heat storage body. The guide ribs are arranged spirally or staggered along the airflow direction, which significantly extends the flow path of the exhaust gas in the combustion chamber. This significantly extends the residence time of the exhaust gas in the high-temperature zone. Based on the high-temperature environment provided by the heat storage body, more sufficient reaction time is provided for difficult-to-decompose gases such as perfluorocarbons, further improving the decomposition efficiency. At the same time, it effectively improves the flow field distribution in the combustion chamber, avoids airflow short-circuiting, and achieves the dual effect of greenhouse gas emission reduction and operating energy consumption reduction.

[0021] Preferably, the furnace body is further provided with a pre-separation mechanism, which includes a separation chamber, a plurality of guide vanes for guiding the exhaust gas to generate a swirling flow, a dust collection chamber for collecting solid particles separated by the swirling flow, and a dust discharge port for periodically discharging the collected dust. The separation chamber has an air inlet and an air outlet. The air inlet is connected to the exhaust gas inlet, and the air outlet is connected to the cold side channel inlet of the heat exchanger. The plurality of guide vanes are disposed in the separation chamber, the dust collection chamber is disposed at the bottom of the separation chamber, and the dust discharge port is disposed at the bottom of the dust collection chamber.

[0022] By adopting the above technical solution, the separation chamber has an air inlet and an air outlet. The air inlet is connected to the exhaust gas inlet, and the air outlet is connected to the cold side channel inlet of the heat exchanger. Several guide vanes are arranged in the separation chamber, the dust collection chamber is arranged at the bottom of the separation chamber, and the dust discharge port is arranged at the bottom of the dust collection chamber. During the process of using this device for waste gas treatment, the guide vanes are used to guide the waste gas to generate a swirling flow, so that the solid particles entrained in the waste gas are thrown against the cavity wall and settled in the dust collection cavity under the action of centrifugal force, and then discharged periodically through the dust discharge port, thereby achieving the source control of dust. This structure removes most of the dust before the exhaust gas enters the heat exchanger, significantly reducing the risk of blockage in the cold side passage of the heat exchanger, greatly extending the cleaning cycle, reducing equipment maintenance frequency and operating costs, and effectively solving the problems of pipe blockage and equipment wear caused by silica dust generated by silicon-containing exhaust gas in the prior art.

[0023] In summary, this application includes at least one of the following beneficial technical effects: 1. When using this device for waste gas treatment, the waste gas to be treated enters the cold side channel of the heat exchanger through the waste gas inlet. At this time, the waste gas to be treated exchanges heat with the high-temperature waste gas flowing through the hot side channel in the heat exchanger. After absorbing heat, the waste gas is heated to the preset preheating temperature. The heated waste gas to be treated enters the air inlet side of the combustion chamber through the cold side channel outlet of the heat exchanger. The burner provides heat to the combustion chamber, so that the inside of the combustion chamber is maintained at the preset high-temperature decomposition temperature. The waste gas to be treated is fully combusted and decomposed in the combustion chamber, and transformed into harmless or low-harm substances. The high-temperature waste gas generated by combustion is discharged from the outlet side of the combustion chamber and enters the hot side channel of the heat exchanger through the inlet of the hot side channel. During the flow through the hot side channel, the high-temperature waste gas exchanges heat with the waste gas to be treated in the cold side channel and releases heat to cool down. The cooled waste gas is discharged through the hot side channel outlet and the waste gas outlet of the heat exchanger. This device uses the high-temperature exhaust gas generated by combustion to preheat the exhaust gas to be treated before it enters the combustion chamber, which significantly increases the initial temperature of the exhaust gas to be treated, thereby reducing the auxiliary fuel consumption required to maintain the high temperature of the combustion chamber, realizing the cascade utilization of waste heat, and effectively solving the technical problems of low waste heat utilization rate and high operating cost in the existing technology. 2. During the process of using this device for waste gas treatment, the waste gas cooled by the heat exchanger is discharged from the waste gas outlet and enters the collection box through the duct. The waste gas first enters the lower space of the collection box; then, the waste gas flows upward in the collection box and flows through several staggered baffles in sequence. During the flow through the baffles, the flow direction of the waste gas changes continuously. The acid mist particles carried in the waste gas collide with the surface of the baffles due to inertia and condense into droplets. The condensed droplets flow downwards along the surface of the baffle plate under the action of gravity, and finally drip into the liquid collection tank at the bottom of the collection box. The acidic liquid collected in the liquid collection tank is discharged to the waste liquid treatment system through the drain pipe. The purified exhaust gas after the acid mist is removed continues to flow upwards and enters the external exhaust pipe through the gas collection pipe in the collection box, and is finally discharged into the subsequent treatment system or discharged in compliance with standards. This effectively avoids acid mist from entering the downstream fan and exhaust pipe, significantly reduces the risk of corrosion inside the equipment and pipelines, and solves the problem of secondary corrosion caused by acidic aerosols in the existing technology. 3. During the waste gas treatment process using this device, the waste gas, after high-temperature combustion and decomposition in the combustion chamber, is discharged from the outlet side of the combustion chamber and enters the cavity through the inlet. The pH sensor monitors the pH value of the condensate in the cavity in real time and sends the pH signal to the control circuit board. The control circuit board compares the received pH signal with the preset pH threshold. When the pH signal is lower than the preset threshold (e.g., pH < 7), the control circuit board controls the metering pump to start, injecting the alkaline neutralizing solution from the alkaline storage tank into the water supply pipeline in a metered manner. After mixing with the cooling water, the solution is sprayed into the cavity through several atomizing nozzles. When the pH signal returns to the preset threshold range, the control circuit board controls the metering pump to stop. During the process of spraying a mixture of cooling water and alkaline neutralizing liquid into the cavity from the atomizing nozzle, the mixture comes into direct contact with the high-temperature exhaust gas. On the one hand, the exhaust gas temperature is rapidly reduced by absorbing heat through the evaporation of water, bringing the exhaust gas temperature down to a range that subsequent equipment can withstand (such as 200℃-300℃). On the other hand, the alkaline neutralizing liquid in the mixture reacts with the acidic gases (such as hydrofluoric acid, hydrochloric acid, etc.) in the exhaust gas to generate neutral salts, thus inhibiting the presence of acidic gases at the source. After cooling and neutralization, the exhaust gas is discharged from the outlet and enters the hot side channel of the heat exchanger for subsequent waste heat recovery. The condensate generated by the spraying and the salts generated by the neutralization reaction are collected at the bottom of the cavity and discharged to the waste liquid treatment system through the drain port. This effectively solves the equipment corrosion problem caused by acidic gases and acid mist in the existing technology, and significantly improves the operational stability and service life of the equipment. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the overall structure of a waste gas combustion furnace for semiconductor production according to an embodiment of this application.

[0025] Figure 2 This is a schematic diagram of the internal structure of the furnace body in an embodiment of this application.

[0026] Figure 3 This is a schematic diagram of the internal structure of the trapping box in an embodiment of this application.

[0027] Figure 4 This is a schematic diagram of the connection structure of the rapid cooling and conditioning mechanism in the embodiments of this application.

[0028] Figure 5 This is a schematic diagram of the internal structure of the cavity component in an embodiment of this application.

[0029] Explanation of reference numerals in the attached figures: 1. Furnace body; 11. Fuel supply rack; 2. Combustion chamber; 3. Burner; 4. Heat exchanger; 5. Exhaust gas inlet; 6. Exhaust gas outlet; 7. Acid mist collection mechanism; 71. Collection box; 711. Liquid collection tank; 7111. Protrusion block; 72. Conduit; 73. Baffle plate; 74. Gas collection pipe; 75. Liquid discharge pipe; 8. Rapid cooling and conditioning mechanism; 81. Cavity components; 811. Gas inlet; 812. Gas outlet; 813. Liquid discharge pipe; 82. Several atomizing nozzles; 83. Water supply pipe; 84. Alkali storage tank; 85. Metering pump. Detailed Implementation

[0030] The present application will be further described in detail below with reference to the accompanying drawings.

[0031] This application discloses a waste gas combustion furnace for semiconductor manufacturing. (Refer to...) Figure 1 and Figure 2 As shown, a waste gas combustion furnace for semiconductor production includes a furnace body 1, a combustion chamber 2, a burner 3, a heat exchanger 4, a waste gas inlet 5, a waste gas outlet 6, an acid mist collection mechanism 7, a rapid cooling and conditioning mechanism 8, and a pre-separation mechanism.

[0032] Reference Figure 1 and Figure 2 As shown, the furnace body 1 is horizontally arranged, the combustion chamber 2 is arranged inside the cavity of the furnace body 1, the burner 3 is arranged inside the combustion chamber 2, and the heat exchanger 4 is arranged inside the cavity of the furnace body 1. The heat exchanger 4 has a cold side channel and a hot side channel. A fuel supply rack 11 is arranged on the furnace body 1, and the exhaust gas inlet 5 is arranged on the furnace body 1. The exhaust gas inlet 5 is connected to the cold side channel inlet of the heat exchanger 4. The exhaust gas outlet 6 is arranged on the furnace body 1 and is connected to the hot side channel outlet of the heat exchanger 4. The cold side passage outlet of the heat exchanger 4 is connected to the intake side of the combustion chamber 2, and the hot side passage inlet of the heat exchanger 4 is connected to the exhaust side of the combustion chamber 2.

[0033] Reference Figure 1 and Figure 2 As shown, when using this device for waste gas treatment, the waste gas to be treated enters the cold side channel of the heat exchanger 4 through the waste gas inlet 5. At this time, the waste gas to be treated exchanges heat with the high-temperature waste gas flowing through the hot side channel in the heat exchanger 4, absorbs heat and rises to the preset preheating temperature. The heated waste gas to be treated enters the air inlet side of the combustion chamber 2 through the cold side channel outlet of the heat exchanger 4. The burner 3 provides heat to the combustion chamber 2, so that the inside of the combustion chamber 2 is maintained at the preset high-temperature decomposition temperature. The waste gas to be treated is fully combusted and decomposed in the combustion chamber 2, and transformed into harmless or low-harm substances. The high-temperature waste gas generated by combustion is discharged from the outlet side of the combustion chamber 2 and enters the hot side channel through the inlet of the hot side channel of the heat exchanger 4. During the flow through the hot side channel, the high-temperature waste gas exchanges heat with the waste gas to be treated in the cold side channel and releases heat to cool down. The cooled waste gas is discharged through the hot side channel outlet and waste gas outlet 6 of the heat exchanger 4. This device uses the high-temperature exhaust gas generated by combustion to preheat the exhaust gas to be treated before it enters the combustion chamber 2, which significantly increases the initial temperature of the exhaust gas to be treated, thereby reducing the auxiliary fuel consumption required to maintain the high temperature of the combustion chamber 2, realizing the cascade utilization of waste heat, and effectively solving the technical problems of low waste heat utilization rate and high operating cost in the existing technology.

[0034] Reference Figure 1 , Figure 2 and Figure 3 As shown, the acid mist collection mechanism 7 includes a collection box 71, a conduit 72, a baffle plate 73, a gas collecting pipe 74, and a liquid discharge pipe 75. Several baffle plates 73 are staggered inside the collection box 71. One end of the conduit 72 is connected to the exhaust gas outlet 6, and the other end of the conduit 72 extends into the collection box 71. The gas collecting pipe 74 is installed inside the collection box 71 and is connected to the external exhaust pipe. A liquid collection tank 711 is installed inside the collection box 71. One end of the liquid discharge pipe 75 is connected to the waste liquid treatment system, and the other end of the liquid discharge pipe 75 is connected to the liquid collection tank 711. During the process of using this device for waste gas treatment, the waste gas cooled by the heat exchanger 4 is discharged from the waste gas outlet 6 and enters the collection box 71 through the duct 72. The waste gas first enters the lower space of the collection box 71; then, the waste gas flows upward in the collection box 71 and flows through several staggered baffles 73 in sequence. During the flow through the baffles 73, the flow direction of the waste gas changes continuously. The acid mist particles carried in the waste gas collide with the surface of the baffles 73 due to inertia and condense into droplets. The condensed droplets flow downwards along the surface of the baffle plate 73 under the action of gravity, and finally drip into the liquid collection tank 711 located at the bottom of the collection box 71. The acidic liquid collected in the liquid collection tank 711 is discharged to the waste liquid treatment system through the drain pipe 75. The purified exhaust gas after the acid mist is removed continues to flow upwards and enters the external exhaust pipe through the gas collection pipe 74 located in the collection box 71, and is finally discharged into the subsequent treatment system or discharged in compliance with standards. This effectively avoids acid mist from entering the downstream fan and exhaust pipe, significantly reduces the risk of corrosion inside the equipment and pipelines, and solves the problem of secondary corrosion caused by acidic aerosols in the prior art.

[0035] Reference Figure 1 and Figure 3As shown, the bottom of the liquid collection tank 711 has an inclined structure that gradually converges towards the drain pipe 75. Several protrusions 7111 are provided on the inner wall of the liquid collection tank 711. The protrusions 7111 are arranged in an array, so that the acidic liquid dripping from the baffle plate 73 will automatically collect along the inclined structure to the drain pipe 75 under the action of gravity, thus avoiding the accumulation and residue of liquid at the bottom of the liquid collection tank 711. Meanwhile, when the exhaust gas enters the bottom of the collection box 71 and flows over the liquid collection tank 711, the array of protrusions 7111 increases the contact area between the exhaust gas and the inner wall of the liquid collection tank 711, and generates local turbulence on the airflow, thereby increasing the residence time of the gas in the area of ​​the liquid collection tank 711. This allows the acid mist particles entrained in the exhaust gas to have more time to settle or adhere to the surface of the protrusions 7111 and condense and drip down, further improving the acid mist collection efficiency.

[0036] Reference Figure 1 and Figure 2 As shown, the inner wall of the hot side channel of the heat exchanger 4 and the inner wall of the exhaust gas outlet 6 are provided with a corrosion-resistant coating. The corrosion-resistant coating is a multi-layer composite structure, which includes, from the inside to the outside: a ceramic bottom layer, a nickel-based alloy intermediate layer and a polytetrafluoroethylene top layer. The ceramic bottom layer is directly attached to the surface of the metal substrate and has excellent thermal stability and chemical inertness. It can effectively prevent acidic gases in the high-temperature exhaust gas from directly contacting the metal substrate, and at the same time act as a thermal barrier to reduce the temperature fluctuation of the substrate surface. The nickel-based alloy intermediate layer is positioned between the ceramic substrate and the polytetrafluoroethylene (PTFE) top layer. On one hand, it serves as a transition layer to enhance the adhesion between the coating and the substrate. On the other hand, it has excellent corrosion resistance and can form a second protective barrier in the intermediate layer. The PTFE top layer, as the outermost layer, has excellent chemical corrosion resistance, hydrophobicity, and a low coefficient of friction. It can effectively resist the erosion of strong acidic media such as hydrofluoric acid and hydrochloric acid. At the same time, its hydrophobic properties make it difficult for condensate droplets to adhere to the coating surface, reducing the contact time between droplets and the coating, and further reducing the risk of corrosion.

[0037] Reference Figure 1 , Figure 2 , Figure 4 and Figure 5 As shown, the rapid cooling and conditioning mechanism 8 includes a cavity component 81, several atomizing nozzles 82, a water supply pipeline 83, an alkali storage tank 84, a metering pump 85, a control circuit board, and a pH sensor. The cavity component 81 has an air inlet 811, an air outlet 812, and a liquid drain 813. The air inlet 811 is connected to the air outlet side of the combustion chamber 2, and the air outlet 812 is connected to the hot side channel inlet of the heat exchanger 4. An alkaline storage tank 84 is located next to the cavity component 81. The alkaline storage tank 84 stores alkaline neutralizing solution. A water supply pipeline 83 is connected to an atomizing nozzle. A metering pump 85 is located between the alkaline storage tank 84 and the water supply pipeline 83. Several atomizing nozzles 82 are located inside the cavity component 81. A control circuit board is located on the furnace body 1. A pH sensor is located inside the cavity component 81. The control circuit board is electrically connected to the pH sensor and the metering pump 85, respectively. During the waste gas treatment process using this device, the waste gas, after being decomposed by high-temperature combustion in the combustion chamber 2, is discharged from the outlet side of the combustion chamber 2 and enters the cavity component 81 through the inlet 811. The pH sensor monitors the pH value of the condensate in the cavity component 81 in real time and sends the pH signal to the control circuit board. The control circuit board compares the received pH signal with the preset pH threshold. When the pH signal is lower than the preset threshold (e.g., pH < 7), the control circuit board controls the metering pump 85 to start, injecting the alkaline neutralizing liquid in the alkaline storage tank 84 into the water supply pipeline 83 in a metered manner. After mixing with the cooling water, the liquid is sprayed into the cavity component 81 through several atomizing nozzles 82. When the pH signal returns to the preset threshold range, the control circuit board controls the metering pump 85 to stop. During the process of the atomizing nozzle spraying a mixture of cooling water and alkaline neutralizing liquid into the cavity 81, the mixture comes into direct contact with the high-temperature exhaust gas. On the one hand, the exhaust gas temperature is rapidly reduced by absorbing heat through the evaporation of water, so that the exhaust gas temperature is reduced to a range that subsequent equipment can withstand (such as 200℃-300℃). On the other hand, the alkaline neutralizing liquid in the mixture reacts with the acidic gases (such as hydrofluoric acid, hydrochloric acid, etc.) in the exhaust gas to generate neutral salts, thus inhibiting the presence of acidic gases at the source. After cooling and neutralization, the exhaust gas is discharged from the outlet 812 and enters the hot side channel of the heat exchanger 4 for subsequent waste heat recovery. The condensate generated by the spraying and the salts generated by the neutralization reaction are collected at the bottom of the cavity 81 and discharged to the waste liquid treatment system through the drain port. This effectively solves the equipment corrosion problem caused by acidic gases and acid mist in the existing technology, and significantly improves the operational stability and service life of the equipment.

[0038] Reference Figure 1 and Figure 2 As shown, a heat storage body for absorbing and storing combustion heat is provided in the combustion chamber 2. The heat storage body is located downstream of the flame injection direction of the burner 3. The heat storage body is a honeycomb ceramic structure or a metal wire mesh structure. During the waste gas treatment process using this device, the high-temperature flame generated by the burner 3 heats the heat storage body to a high temperature. When the waste gas to be treated enters the combustion chamber 2, it is first heated in the flame area and then heated a second time when it flows through the heat storage body. This allows the waste gas temperature to reach the decomposition temperature of difficult-to-decompose gases such as perfluorocarbons more quickly. At the same time, the heat storage body acts as a heat buffer medium, maintaining a stable furnace temperature when the flame fluctuates or the waste gas flow changes. This significantly improves the decomposition efficiency of perfluorocarbons and reduces greenhouse gas emissions, while effectively reducing auxiliary fuel consumption, achieving the dual effects of energy saving and high-efficiency purification.

[0039] Reference Figure 1 and Figure 2 As shown, the combustion chamber 2 is equipped with several guide ribs, which are located on the inner wall of the combustion chamber 2 and downstream of the heat storage body. The guide ribs are arranged spirally or staggered along the airflow direction. This significantly extends the flow path of the exhaust gas in the combustion chamber 2, thereby significantly extending the residence time of the exhaust gas in the high-temperature zone. Based on the high-temperature environment provided by the heat storage body, it provides more sufficient reaction time for difficult-to-decompose gases such as perfluorocarbons, further improving the decomposition efficiency. At the same time, it effectively improves the flow field distribution in the combustion chamber 2, avoids airflow short-circuiting, and achieves the dual effect of greenhouse gas emission reduction and operating energy consumption reduction.

[0040] Reference Figure 1 and Figure 2 As shown, the pre-separation mechanism includes a separation chamber, several guide vanes, a dust collection chamber, and a dust discharge port. The separation chamber has an air inlet and an air outlet. The air inlet is connected to the exhaust gas inlet 5, and the air outlet is connected to the cold side channel inlet of the heat exchanger 4. Several guide vanes are arranged in the separation chamber, the dust collection chamber is located at the bottom of the separation chamber, and the dust discharge port is located at the bottom of the dust collection chamber. During the process of using this device for waste gas treatment, the guide vanes are used to guide the waste gas to generate a swirling flow, so that the solid particles entrained in the waste gas are thrown against the cavity wall and settled in the dust collection cavity under the action of centrifugal force, and then discharged periodically through the dust discharge port, thereby achieving the source control of dust. This structure removes most of the dust before the exhaust gas enters the heat exchanger 4, significantly reducing the risk of blockage in the cold side channel of the heat exchanger 4, greatly extending the cleaning cycle, reducing the frequency of equipment maintenance and operating costs, and effectively solving the problems of pipe blockage and equipment wear caused by silica dust generated by silicon-containing exhaust gas in the prior art.

[0041] The implementation principle of a waste gas combustion furnace for semiconductor production according to an embodiment of this application is as follows: When using this device for waste gas treatment, the waste gas to be treated enters the cold side channel of the heat exchanger 4 through the waste gas inlet 5. At this time, the waste gas to be treated exchanges heat with the high-temperature waste gas flowing through the hot side channel in the heat exchanger 4. After absorbing heat, the waste gas is heated to the preset preheating temperature. The heated waste gas to be treated enters the air inlet side of the combustion chamber 2 through the cold side channel outlet of the heat exchanger 4. The burner 3 provides heat to the combustion chamber 2, so that the inside of the combustion chamber 2 is maintained at the preset high-temperature decomposition temperature. The waste gas to be treated is fully combusted and decomposed in the combustion chamber 2, and transformed into harmless or low-harm substances. The high-temperature waste gas generated by combustion is discharged from the outlet side of the combustion chamber 2 and enters the hot side channel through the inlet of the hot side channel of the heat exchanger 4. During the flow through the hot side channel, the high-temperature waste gas exchanges heat with the waste gas to be treated in the cold side channel and releases heat to cool down. The cooled waste gas is discharged through the hot side channel outlet and waste gas outlet 6 of the heat exchanger 4. This device uses the high-temperature exhaust gas generated by combustion to preheat the exhaust gas to be treated before it enters the combustion chamber 2, which significantly increases the initial temperature of the exhaust gas to be treated, thereby reducing the auxiliary fuel consumption required to maintain the high temperature of the combustion chamber 2, realizing the cascade utilization of waste heat, and effectively solving the technical problems of low waste heat utilization rate and high operating cost in the existing technology.

[0042] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A waste gas combustion furnace for semiconductor manufacturing, comprising a furnace body (1), characterized in that, Also includes: Combustion chamber (2) is disposed within the cavity of the furnace body (1); A burner (3) is disposed in the combustion chamber (2) and is used to provide heat to the combustion chamber (2); A heat exchanger (4) is disposed in the cavity of the furnace body (1), and the heat exchanger (4) has a cold side channel and a hot side channel; The exhaust gas inlet (5) is located on the furnace body (1) and is connected to the cold side channel inlet of the heat exchanger (4); The exhaust gas outlet (6) is located on the furnace body (1) and is connected to the hot side channel outlet of the heat exchanger (4); The cold side outlet of the heat exchanger (4) is connected to the air intake side of the combustion chamber (2), and the hot side inlet of the heat exchanger (4) is connected to the air outlet side of the combustion chamber (2).

2. The waste gas combustion furnace for semiconductor production according to claim 1, characterized in that: The furnace body (1) is also equipped with an acid mist collection mechanism (7). The acid mist collection mechanism (7) includes a collection box (71), a conduit (72) connected to the exhaust gas outlet (6) at one end, several baffles (73) arranged alternately in the collection box (71), a gas collection pipe (74) arranged in the collection box (71), and a drain pipe (75) connected to the waste liquid treatment system at one end. A liquid collection tank (711) is provided in the collection box (71). The other end of the drain pipe (75) is connected to the liquid collection tank (711). The other end of the conduit (72) extends into the collection box (71). The gas collection pipe (74) is connected to the external exhaust pipe.

3. The waste gas combustion furnace for semiconductor production according to claim 2, characterized in that: The bottom of the liquid collection tank (711) is inclined towards the drain pipe (75). The inner wall of the liquid collection tank (711) is provided with a number of protrusions (7111). The protrusions (7111) are arranged in an array to increase the residence time of gas in the liquid collection tank (711).

4. The waste gas combustion furnace for semiconductor production according to claim 1, characterized in that: The inner wall of the heat exchanger (4) heat-side channel and the inner wall of the exhaust gas outlet (6) are provided with a corrosion-resistant coating. The corrosion-resistant coating is a multi-layer composite structure, which includes, from the inside to the outside: a ceramic bottom layer, a nickel-based alloy intermediate layer and a polytetrafluoroethylene top layer.

5. A waste gas combustion furnace for semiconductor production according to claim 1, characterized in that: The furnace body (1) is also equipped with a rapid cooling and conditioning mechanism (8), which includes a cavity component (81), a plurality of atomizing nozzles (82) disposed in the cavity component (81), a water supply pipeline (83) connected to the atomizing nozzles, an alkaline storage tank (84) for storing alkaline neutralizing solution, a metering pump (85) disposed between the alkaline storage tank (84) and the water supply pipeline (83), a control circuit board, and a pH sensor disposed in the cavity component (81). The cavity component (81) has an air inlet (811) and an air outlet (812). The air inlet (811) is connected to the exhaust side of the combustion chamber (2), the exhaust outlet (812) is connected to the hot side channel inlet of the heat exchanger (4), a plurality of atomizing nozzles are used to spray cooling water into the cavity (81), the metering pump (85) is used to inject the alkaline neutralizing liquid in the alkaline storage tank (84) into the water supply pipeline (83), the control circuit board is electrically connected to the pH sensor and the metering pump (85) respectively, and the control circuit board is configured to control the start and stop and flow rate of the metering pump (85) according to the pH signal fed back by the pH sensor.

6. A waste gas combustion furnace for semiconductor manufacturing according to claim 1, characterized in that: The combustion chamber (2) is provided with a heat storage body for absorbing and storing combustion heat. The heat storage body is located downstream of the flame jet direction of the burner (3). The heat storage body is a honeycomb ceramic structure or a metal wire mesh structure.

7. A waste gas combustion furnace for semiconductor manufacturing according to claim 6, characterized in that: The combustion chamber (2) is provided with several guide ribs for extending the flow path of exhaust gas in the combustion chamber (2). The several guide ribs are disposed on the inner wall of the combustion chamber (2) and located downstream of the heat storage body. The guide ribs are arranged spirally or staggered along the airflow direction.

8. A waste gas combustion furnace for semiconductor manufacturing according to claim 1, characterized in that: The furnace body (1) is also provided with a pre-separation mechanism. The pre-separation mechanism includes a separation chamber, several guide vanes for guiding the waste gas to generate a swirling flow, a dust collection chamber for collecting solid particles separated by the swirling flow, and a dust discharge port for periodically discharging the collected dust. The separation chamber has an air inlet and an air outlet. The air inlet is connected to the waste gas inlet (5), and the air outlet is connected to the cold side channel inlet of the heat exchanger (4). Several guide vanes are arranged in the separation chamber. The dust collection chamber is located at the bottom of the separation chamber, and the dust discharge port is located at the bottom of the dust collection chamber.

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