CN-122013142-A - Tail gas treatment method and equipment based on CVD coating process

CN122013142ACN 122013142 ACN122013142 ACN 122013142ACN-122013142-A

Abstract

The application discloses a tail gas treatment method and equipment based on a CVD coating process, which comprise the steps of obtaining tail gas flow data in a tail gas pipeline, adjusting the flow rate of the tail gas pipeline according to the difference value between the tail gas flow data and a target flow rate, obtaining temperature data at two opposite ends of the tail gas pipeline, adjusting the temperatures at two opposite ends of the tail gas pipeline according to the difference value between the temperature data and a preset temperature, obtaining a scale formation state value in the tail gas pipeline, introducing nitrogen into the tail gas pipeline if the scale formation state value is larger than the preset threshold value, obtaining a pressure value in the tail gas pipeline, and adjusting the introducing amount and the introducing time of the nitrogen according to the pressure value, so as to complete a tail gas treatment flow. The application improves the adaptability of the tail gas treatment system to complex working conditions by comprehensively regulating and controlling the flow rate, the temperature, the scaling state and the pressure in the tail gas pipeline, and solves the problems of low treatment efficiency and high maintenance cost caused by pipeline layout limitation, high-temperature heat tracing band damage, increased maintenance difficulty of heat-insulating cotton and scaling in the prior art.

Inventors

SUN LI
LIU LINA
LU XIAOYING

Assignees

广州志橙半导体有限公司

Dates

Publication Date: 20260512
Application Date: 20260227

Claims (10)

1. A method for treating an exhaust gas of a CVD apparatus, comprising: providing a tail gas pipeline, connecting the tail gas pipeline with a CVD device, acquiring tail gas flow data in the tail gas pipeline, and adjusting the flow rate of the tail gas pipeline according to the difference value between the tail gas flow data and a target flow rate; Acquiring temperature data of the two opposite ends of the tail gas pipeline, and adjusting the temperatures of the two opposite ends in the tail gas pipeline according to the difference value between the temperature data and the preset temperature; acquiring a scaling state value in the tail gas pipeline, and if the scaling state value is larger than a preset threshold value, introducing nitrogen into the tail gas pipeline; And obtaining a pressure value in the tail gas pipeline, and adjusting the inlet amount and the inlet time of nitrogen according to the pressure value to finish the tail gas treatment process.
2. The method for treating exhaust gas based on CVD coating process according to claim 1, wherein the step of connecting an exhaust gas pipe with a chemical vapor deposition apparatus to obtain exhaust gas flow rate data in the exhaust gas pipe, and adjusting a flow rate of the exhaust gas pipe according to a difference between the exhaust gas flow rate data and a target flow rate comprises: The tail gas pipeline is in butt joint with a tail gas discharge port of chemical vapor deposition equipment, and flow distribution data in the tail gas pipeline are collected based on a flow sensor in the tail gas pipeline; Calculating the actual flow velocity of each section in the pipeline according to the flow distribution number and the section area parameter of the tail gas pipeline to obtain actual flow velocity distribution data containing flow velocity spatial distribution and time variation; Calculating the flow velocity deviation value of each section in the tail gas pipeline according to the difference value between the actual flow velocity distribution data and the preset target flow velocity, and carrying out weighted average processing on a plurality of flow velocity deviation values according to the change trend of the flow velocity distribution data to obtain a flow velocity deviation parameter; and controlling the running power of the vacuum pump according to the flow rate deviation parameter to adjust the flow rate in the tail gas pipeline, wherein the vacuum pump is respectively connected with the tail gas pipeline and the chemical vapor deposition equipment.
3. The method for treating exhaust gas based on a CVD coating process according to claim 1, wherein the step of acquiring temperature data of opposite ends of the exhaust gas pipe and adjusting the temperatures of the opposite ends in the exhaust gas pipe according to a difference between the temperature data and a preset temperature comprises: Acquiring real-time temperatures of air flows in the tail gas pipeline at two ends based on temperature sensors at an inlet end and an outlet end of the tail gas pipeline, and obtaining initial temperature distribution data comprising time-varying temperatures at the inlet end and the outlet end; the initial temperature distribution data is compared with a preset target temperature point by point to obtain temperature deviation data of temperature deviation of an inlet end and an outlet end; carrying out dynamic adjustment treatment on a temperature control device of the tail gas pipeline according to the temperature deviation parameter to obtain a heat exchange control signal; Acquiring heat compensation values at two ends of the tail gas pipeline according to the temperature deviation distribution parameters, and preheating a heat conducting medium through a heating cavity according to the heat compensation values; Conveying the heat-conducting medium into an output mixed liquid cavity, and carrying out dynamic proportion mixing with the low-temperature heat-conducting medium stored in the normal-temperature cavity to obtain a target temperature medium; And conveying the target temperature medium to a heat exchange area corresponding to the tail gas pipeline, so that the temperatures at the two opposite ends of the tail gas pipeline reach a preset temperature range.
4. The method of claim 1, wherein the step of obtaining the state of fouling value in the exhaust pipe comprises: Transmitting ultrasonic signals to the inner wall of the pipeline based on the multi-point ultrasonic sensor array in the tail gas pipeline, and receiving the acoustic wave signals reflected back by the inner wall of the pipeline to obtain initial acoustic wave reflection data, wherein the initial acoustic wave reflection data comprise acoustic wave propagation time differences of a plurality of sampling points at different time points; calculating the scale thickness of each sampling point on the inner wall of the tail gas pipeline according to the initial sound wave reflection data to generate scale thickness distribution data; And comparing the thickness change of the same sampling point in the scaling thickness distribution data at different time points, and carrying out integrated analysis on the thickness change values of a plurality of sampling points to obtain scaling state values representing the overall scaling degree.
5. The method for treating an exhaust gas based on a CVD coating process according to claim 1, wherein the step of introducing nitrogen into the exhaust gas pipe if the scale formation status value is greater than a predetermined threshold value comprises: comparing the scaling state value with a preset threshold value based on a comparator circuit to generate a trigger signal for controlling nitrogen, wherein the trigger signal is high level, the scaling state value exceeds the preset threshold value, and the low level does not exceed the preset threshold value; And controlling nitrogen to enter the tail gas pipeline through the gas pipeline, so that the nitrogen is distributed in a scaling area on the inner wall of the tail gas pipeline, and forming a nitrogen protection atmosphere covering the tail gas pipeline.
6. The method for treating exhaust gas based on a CVD coating process according to claim 1, wherein the step of obtaining a pressure value in the exhaust gas pipe and adjusting the nitrogen gas introduction amount and the nitrogen gas introduction time according to the pressure value comprises: Acquiring an airflow pressure value in the tail gas pipeline according to a pressure sensor on the inner wall of the tail gas pipeline to obtain initial pressure distribution data; extracting the maximum fluctuation rate and the maximum dropping rate of the pressure value of each sampling point in the initial pressure distribution data to obtain a pressure fluctuation parameter; obtaining an initial adjustment coefficient of nitrogen inflow according to a comparison result of the pressure fluctuation parameter and a preset pressure fluctuation threshold, wherein the initial adjustment coefficient is increased when the pressure fluctuation parameter exceeds the preset pressure fluctuation threshold, and the initial adjustment coefficient is reduced when the pressure fluctuation parameter is lower than the preset pressure fluctuation threshold; Calculating an adjustment value of the nitrogen gas inlet amount based on the product of the initial adjustment coefficient and the real-time pressure value in the tail gas pipeline, and calculating the nitrogen gas inlet time according to the duration time of the pressure fluctuation parameter to form an adjustment parameter; and controlling the running state of the nitrogen supply device according to the adjustment parameters, wherein the nitrogen supply device is connected with an air inlet of the tail gas pipeline through an electromagnetic valve, and the opening of the electromagnetic valve is adjusted according to the adjustment value of the nitrogen inlet.
7. An exhaust gas treatment apparatus, characterized by being applied to a CVD coating process-based exhaust gas treatment method according to any one of claims 1 to 6, comprising: the tail gas pipeline is used for transmitting the tail gas to be treated, and a temperature sensor, an ultrasonic sensor, a pressure sensor and a flow sensor are arranged in the tail gas pipeline; The gas outlet of the tail gas pipeline is provided with a check valve, one end of the vacuum pump is connected with the gas outlet of the chemical vapor deposition equipment, and the other end of the vacuum pump is connected with the gas inlet of the tail gas pipeline through the check valve; the temperature control device is connected with the tail gas pipeline and used for adjusting the temperatures of two opposite ends in the tail gas pipeline; The control unit is respectively and electrically connected with the flow sensor, the temperature sensor, the ultrasonic sensor, the pressure sensor, the vacuum pump and the temperature control device and is used for receiving and processing data acquired by each sensor and generating control signals so as to control the running state of each device and finish the tail gas treatment flow.
8. The tail gas treatment equipment according to claim 7, further comprising a double-layer interlayer, wherein the double-layer interlayer comprises a temperature control interlayer and a heat preservation layer, the temperature control interlayer and the heat preservation layer are sequentially arranged on the outer wall of the tail gas pipeline, and a heat conducting medium with adjustable temperature is filled in the temperature control interlayer and is connected with the temperature control device to regulate and control the temperature of the heat conducting medium.
9. The tail gas treatment device according to claim 7, wherein the tail gas pipeline is of a straight cylindrical structure, and an inclination angle of 0.17-0.5 is arranged in the axial direction of the tail gas pipeline relative to the gas outlet of the chemical vapor deposition device.
10. The tail gas treatment equipment according to claim 7, wherein the temperature control device comprises a heating cavity, a liquid mixing cavity, a refrigerating cavity and a heat conducting medium conveying pipeline, the heating cavity is used for preheating the heat conducting medium, the liquid mixing cavity is used for dynamically mixing the preheated heat conducting medium with the normal-temperature heat conducting medium in proportion to obtain a target temperature medium, the refrigerating cavity is used for cooling the heat conducting medium, and the heat conducting medium conveying pipeline is responsible for conveying the heat conducting medium processed by the heating cavity, the liquid mixing cavity and the refrigerating cavity to a heat exchange area corresponding to the tail gas pipeline.

Description

Tail gas treatment method and equipment based on CVD coating process Technical Field The application relates to the technical field of tail gas treatment, in particular to a tail gas treatment method and equipment based on a CVD coating process. Background Chemical Vapor Deposition (CVD) is a thin film deposition technique that is used in the industrial fields of semiconductors, photovoltaic devices, functional coatings, and the like. However, the tail gas generated by the CVD process contains volatile organic compounds, particulate matter and unreacted chemical substances, which, if not effectively treated, are directly discharged, pose a threat to the environment and human health. In practical application, the existing tail gas treatment technology has a core problem generally, namely, the tail gas treatment system has insufficient adaptability to complex working conditions in a pipeline. In CVD off-gas treatment, the actual layout of the off-gas piping is often limited by the space of the process equipment and production sites, and part of the piping locations are not suitable for frequent disassembly maintenance. To prevent tail gas from condensing or fouling within the pipeline, it is often necessary to coat the heat trace strip outside the pipeline to maintain the pipeline temperature. However, the heat tracing band is easily damaged due to heat loss or local overheating in a high-temperature environment, and particularly in a high-temperature area close to the gas outlet of the reaction cavity, the service life of the heat tracing band is obviously shortened. In order to reduce heat loss, heat preservation cotton is often added outside the heat tracing belt in the prior art, so that the disassembly and maintenance difficulty of the pipeline is further increased, and the problem of scaling at the joint of the pipeline and subsequent treatment equipment (such as a spray tower) is further aggravated. Therefore, a method for treating exhaust gas capable of comprehensively adapting to complex working conditions is needed to improve the operation efficiency and maintenance convenience of the system. Disclosure of Invention The application aims to provide a tail gas treatment method and equipment based on a CVD coating process, which solve the technical problem of insufficient adaptability to complex working conditions in the prior art. In order to achieve the purpose, the application adopts the following technical scheme: A method of treating exhaust gas based on a CVD coating process, comprising: Connecting a tail gas pipeline with chemical vapor deposition equipment, acquiring tail gas flow data in the tail gas pipeline, and adjusting the flow rate of the tail gas pipeline according to the difference value between the tail gas flow data and a target flow rate; Acquiring temperature data of the two opposite ends of the tail gas pipeline, and adjusting the temperatures of the two opposite ends in the tail gas pipeline according to the difference value between the temperature data and the preset temperature; acquiring a scaling state value in the tail gas pipeline, and if the scaling state value is larger than a preset threshold value, introducing nitrogen into the tail gas pipeline; And obtaining a pressure value in the tail gas pipeline, and adjusting the inlet amount and the inlet time of nitrogen according to the pressure value to finish the tail gas treatment process. Further, the step of connecting the tail gas pipeline with the chemical vapor deposition device to obtain the tail gas flow data in the tail gas pipeline, and adjusting the flow rate of the tail gas pipeline according to the difference value between the tail gas flow data and the target flow rate comprises the following steps: The tail gas pipeline is in butt joint with a tail gas discharge port of chemical vapor deposition equipment, and flow distribution data in the tail gas pipeline are collected based on a flow sensor in the tail gas pipeline; Calculating the actual flow velocity of each section in the pipeline according to the flow distribution number and the section area parameter of the tail gas pipeline to obtain actual flow velocity distribution data containing flow velocity spatial distribution and time variation; Calculating the flow velocity deviation value of each section in the tail gas pipeline according to the difference value between the actual flow velocity distribution data and the preset target flow velocity, and carrying out weighted average processing on a plurality of flow velocity deviation values according to the change trend of the flow velocity distribution data to obtain a flow velocity deviation parameter; and controlling the running power of the vacuum pump according to the flow rate deviation parameter to adjust the flow rate in the tail gas pipeline, wherein the vacuum pump is respectively connected with the tail gas pipeline and the chemical vapor deposition equipment. Further, the step of obtaining temper