Gas supply system and control method thereof

Abstract

The invention discloses a gas supply system and a control method thereof, and belongs to the technical field of industrial gas equipment. The air supply system comprises a CDA air compression station and a nitrogen making system, a first communicating pipeline is arranged from the output end of a nitrogen making air compressor of the nitrogen making system to the output end of a CDA air compressor of the CDA air compression station, and a first pressure regulating valve group is arranged on the first communicating pipeline; a second communicating pipeline is arranged from the output end of the molecular sieve purification unit of the nitrogen making system to the output end of the dryer of the CDA air compression station, and a second pressure regulating valve group is arranged on the second communicating pipeline; and a dew point analyzer is arranged at the output end of the drying machine. The two communicating pipelines are arranged between the nitrogen making system and the CDA air compression station, and the pressure regulating valve group is arranged in a matched manner, so that the nitrogen making system can supply air to the CDA air compression station in a linkage manner under two different conditions, the configuration of each air compressor is optimized to the maximum extent, and emptying waste caused by inconsistency of the designed flow of the air compressors and the actual use amount is prevented.

Description

Technical Field

[0001] The present invention belongs to the technical field of industrial gas equipment, and in particular relates to a gas supply system for supplying gas for industrial production and a control method thereof. Background Art

[0002] Compressed dry air (CDA: Clean Dry Air), as the power gas for factory equipment, is the most important driving source, especially for some core processing equipment, which has stringent requirements on the quality (including purity and pressure) and supply stability of compressed dry air. For example, in semiconductor processing factories, many process links require a large amount of compressed dry air, so such factories will build their own dedicated air compression stations to supply CDA.

[0003] This type of air compression station usually includes compressors, heat exchangers, air-water separators, dryers, filters and other devices. The air compressor compresses the air taken from the atmosphere to obtain pressurized room-temperature humid air. The room-temperature humid air passes through the cooler and exchanges heat with chilled water to cool it down, removing some water and water-soluble impurities in the humid air. The low-temperature humid air passes through the dryer to absorb and remove water, thereby obtaining cold dry air with an extremely low dew point. Filters are also set before and after the dryer. Before the cold dry air enters the dryer, it is first filtered through a coarse filter to remove particulate impurities. The cold dry air discharged from the dryer passes through a post-filter to filter out particulate matter to obtain CDA required by the standard and is supplied to the production workshop.

[0004] As we all know, the production capacity of a factory is often invested gradually. Taking the semiconductor factory workshop as an example, the corresponding equipment is gradually moved in and put into use as the production capacity gradually increases. Correspondingly, the gas consumption also gradually increases from a small amount at the beginning to the designed gas consumption; this process takes 3-5 years at least and 8-10 years at most. However, when the air compressor station is built, it is generally necessary to configure it according to the maximum design consumption. Even if the air compressor has a certain load adjustment range, it cannot 100% match the gas demand at different stages. Especially in the capacity climbing stage, the air compressors in the air compressor station will have air venting, which is obviously a waste, and the sound of air venting is very loud, which will cause noise pollution to the environment.

[0005] In addition, nitrogen, as a protective gas, is also widely used in industrial production. For example, most semiconductor factories are often equipped with nitrogen production systems. Nitrogen production systems generally include air compressors, pre-cooling units, pre-purification units, etc.; its working principle is roughly as follows: the raw air is compressed by the air compressor to obtain normal temperature humid air, and the normal temperature humid air is cooled to about 10°C by the pre-cooling unit, and the air entering the molecular sieve purification unit is cooled to reach the temperature entering the purification unit, reducing the water content in the air and removing water-soluble chemical impurities in the air, such as SO2 / NH3 / HCl / NO2 and some fine dust are washed out by the descending cooling water; the low-temperature humid air passes through the purification unit to remove H2O and CO2 in the air, and obtain process air mainly composed of nitrogen.

[0006] The applicant found through testing and analysis that the dew point of the process air obtained by the nitrogen production system meets the quality requirements of CDA. However, the existing CDA air compressor station and the existing nitrogen production system are operated independently, and the air compressor of the nitrogen production system also has the phenomenon of venting at different gas use stages, resulting in a large amount of energy waste. Summary of the invention

[0007] The purpose of the present invention is to provide an air supply system and a control method thereof, aiming to improve the linkage efficiency between the CDA air compressor station and the nitrogen production system and reduce the phenomenon of air compressor venting. The present invention is achieved through the following scheme:

[0008] A gas supply system includes a CDA air compressor station and a nitrogen making system, characterized in that: a first connecting pipeline is provided from the output end of the nitrogen making air compressor of the nitrogen making system to the output end of the CDA air compressor of the CDA air compressor station, and a first pressure regulating valve group is provided on the first connecting pipeline; a second connecting pipeline is provided from the output end of the molecular sieve purification unit of the nitrogen making system to the output end of the dryer of the CDA air compressor station, and a second pressure regulating valve group is provided on the second connecting pipeline; a dew point analyzer is provided on the output end of the dryer.

[0009] As a preferred solution of the above-mentioned air supply system, a first pressure sensor is provided on the first connecting pipeline, and a second pressure sensor is provided at the output end of the dryer.

[0010] As a preferred solution for the above-mentioned air supply system, the CDA air compressor includes a first CDA air compressor and a second CDA air compressor; the design flow of the first CDA air compressor is the CDA gas consumption corresponding to the maximum production capacity of the production workshop, and the design flow of the second CDA air compressor is the minimum CDA gas consumption to ensure uninterrupted gas supply to key equipment in the production workshop.

[0011] As a preferred embodiment of the above-mentioned air supply system, the nitrogen-making air compressor includes a first nitrogen-making air compressor and a second nitrogen-making air compressor; the design flow rate of the first nitrogen-making air compressor is greater than the amount of air required corresponding to the maximum production capacity of the nitrogen-making system, and the design flow rate of the second nitrogen-making air compressor is less than or equal to 50% of the design flow rate of the first nitrogen-making air compressor.

[0012] As a preferred solution of the above-mentioned gas supply system, the gas supply system further includes a pressure boosting and gas buffer component connected in parallel to the second connecting pipeline downstream of the second pressure regulating valve group.

[0013] As a preferred embodiment of the above-mentioned gas supply system, the boosting and gas buffer component includes a supercharger, a high-pressure buffer tank, a third pressure regulating valve group, a first three-way valve and a second three-way valve; the inlet of the supercharger is connected to the second connecting pipeline through the first three-way valve, the inlet of the high-pressure buffer tank is connected to the outlet of the supercharger, the inlet of the third pressure regulating valve group is connected to the outlet of the high-pressure buffer tank, and the outlet of the third pressure regulating valve group is connected to the second connecting pipeline through the second three-way valve.

[0014] Based on the air supply system provided by the above solution, the present invention also provides a control method of the air supply system, including:

[0015] According to the current CDA gas consumption, it is judged whether the CDA air compressor station needs to be supplemented with gas by the nitrogen making system and whether the gas supplementation conditions of the nitrogen making system are met. If yes, the first pressure regulating valve group is opened and the nitrogen making system supplements gas to the CDA air compressor station through the first connecting pipeline. Otherwise, the CDA air compressor station supplies gas by itself.

[0016] When the nitrogen making system supplies air to the CDA air compressor station through the first connecting pipeline, the dew point data at the output end of the dryer is monitored in real time to see whether it meets the standard. If it does not meet the standard, the second pressure regulating valve group is opened and the first pressure regulating valve group is closed, and the nitrogen making system supplies air to the CDA air compressor station through the second connecting pipeline.

[0017] As a preferred solution of the control method of the above-mentioned gas supply system, the specific control method of the nitrogen production system supplying gas to the CDA air compressor station through the first connecting pipeline or the CDA air compressor station supplying gas by itself includes:

[0018] S1: The CDA air compressor is configured as a first CDA air compressor and a second CDA air compressor; the design flow rate W1 of the first CDA air compressor is the CDA gas consumption corresponding to the maximum production capacity of the production workshop, and the design flow rate W2 of the second CDA air compressor is the minimum CDA gas consumption to ensure uninterrupted gas supply to key equipment in the production workshop;

[0019] S2: Determine the interval of the current CDA gas consumption V. If V≧W1*70%, proceed to step S3A; if W1*70%>V≧W2, proceed to step S3B; if W2>V, proceed to step S3C;

[0020] S3A: Start the first CDA air compressor to supply CDA air;

[0021] S3B: starting the second CDA air compressor to supply CDA gas, and at the same time opening the first pressure regulating valve group, using the first connecting pipeline to use the gas output by the nitrogen-making air compressor as a supplement to the CDA gas supply;

[0022] S3C: Start the second CDA air compressor to supply CDA air.

[0023] As a preferred solution of the control method of the above-mentioned gas supply system, the specific control method of the nitrogen making system and the nitrogen making system gas replenishment conditions are met, including:

[0024] S10: configuring the nitrogen-generating air compressor into a first nitrogen-generating air compressor and a second nitrogen-generating air compressor; the design flow rate Q1 of the first nitrogen-generating air compressor is greater than the air volume S required for the maximum capacity of the nitrogen-generating air compressor, and the design flow rate Q2 of the second nitrogen-generating air compressor is less than or equal to 50% of the design flow rate of the first nitrogen-generating air compressor;

[0025] S20: Determine the interval of the current CDA gas consumption V. If V+S≤Q1, proceed to step S30A; if Q1+Q2≥V+S≥Q1, proceed to step S30B; if V+S≥Q1+Q2, proceed to step S30C;

[0026] S30A: starting the first nitrogen-making air compressor to supply gas to the nitrogen-making system and opening the first pressure regulating valve group, using the first connecting pipeline to use the gas output by the first nitrogen-making air compressor as a supplement to the CDA gas supply;

[0027] S30B: starting the first nitrogen making air compressor and the second nitrogen making air compressor to supply gas to the nitrogen making system while opening the first pressure regulating valve group, and using the first connecting pipeline to use the gas output by the first nitrogen making air compressor as a supplement to the CDA gas supply;

[0028] S30C: The first nitrogen making air compressor and the second nitrogen making air compressor only supply air to the nitrogen making system.

[0029] As a preferred solution of the control method of the above-mentioned gas supply system, it also includes: configuring a boosting and gas buffer component for the CDA air compressor station, controlling the boosting and gas buffer component to boost and buffer the excess gas at the output end of the CDA air compressor station, and controlling the boosting and gas buffer component to release the buffered gas to the output end of the CDA air compressor station.

[0030] The air supply system and control method provided by the present invention have the following beneficial effects: the air is supplied to the CDA air compressor station in linkage through the nitrogen making system, and a pressure regulating valve group is matched to realize interconnection and automatic adjustment under the premise of stable operation of each air compressor, optimize the configuration of the air compressor to the maximum extent, reduce energy consumption, and prevent the waste of venting due to the inconsistency between the design flow rate of the air compressor and the actual usage; moreover, the design flow rates of the CDA air compressor and the nitrogen making air compressor can be appropriately reduced to reduce investment costs; in addition, under normal air supply conditions, the CDA air compressor station selects the first connecting pipeline to obtain compressed air from the nitrogen making system. When the CDA air compressor station has abnormal fluctuations, resulting in the CDA dew point not meeting the standard, the CDA air compressor station can obtain the process air treated by the nitrogen making system from the nitrogen making system through the second connecting pipeline for use as CDA, thereby ensuring the quality of air supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A structural diagram of a gas supply system provided for a specific embodiment of the present invention.

[0032] Figure 2 This is a main flow chart of a method for controlling a gas supply system according to a specific embodiment of the present invention.

[0033] Figure 3 A sub-flow chart of a specific control method for a nitrogen production system to supplement air to a CDA air compressor station through a first connecting pipeline or for a CDA air compressor station to supply air by itself in a control method for an air supply system provided in a specific embodiment of the present invention.

[0034] Figure 4 A sub-flow chart of the control method of the gas supply system provided in the specific embodiment of the present invention, which satisfies the gas replenishment conditions of the nitrogen production system and the specific control method of the nitrogen production system.

[0035] Figure 5 The hardware architecture on which the control method of the air supply system provided in the specific embodiment of the present invention is based. DETAILED DESCRIPTION

[0036] The technical solutions of the embodiments of the present invention are explained and described below in conjunction with the drawings of the embodiments of the present invention, but the following embodiments are only preferred embodiments of the present invention, not all of them. In the description of the present invention, the terms "first" and "second" are only used for the purpose of distinction in the description, 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" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more, unless otherwise clearly defined.

[0037] The specific implementation modes of the present invention are described in detail below with reference to the accompanying drawings. The technical features of each specific implementation mode can be used interchangeably without conflicting with each other.

[0038] like Figure 1 As shown, the gas supply system provided in this embodiment includes a CDA air compression station and a nitrogen production system. The CDA air compression station includes a CDA air compressor 11, a low-pressure buffer tank 12, a precooler 13, a steam-water separator 14, a coarse filter 15, a dryer 16 and a fine filter 17 connected in sequence; the nitrogen production system includes a nitrogen production air compressor 21, a precooling unit 22 and a molecular sieve purification unit 23 connected in sequence.

[0039] As a basic implementation, the gas supply system provided in this embodiment further includes a first connecting pipeline 311 , a first pressure regulating valve group 312 , a second connecting pipeline 321 , a second pressure regulating valve group 322 and a dew point analyzer 33 . Among them, a first connecting pipeline 311 is set from the output end of the nitrogen making air compressor 21 of the nitrogen making system to the output end of the CDA air compressor 11 of the CDA air compressor station, and a first pressure regulating valve group 312 is set on the first connecting pipeline 311, which is used to control the opening and closing and air pressure of the gas when it flows from the output end of the nitrogen making air compressor 21 to the output end of the CDA air compressor 11; a second connecting pipeline 321 is set from the output end of the molecular sieve purification unit 23 of the nitrogen making system to the output end of the dryer 16 of the CDA air compressor station, and a second pressure regulating valve group 322 is set on the second connecting pipeline 321, which is used to control the opening and closing and air pressure of the gas when it flows from the output end of the molecular sieve purification unit 23 to the output end of the dryer 16; a dew point analyzer 33 is set at the output end of the dryer 16, which is used to monitor the dew point of the gas output by the dryer 16. The control module of the air supply system provided in this embodiment controls the first pressure regulating valve group 312 and the second pressure regulating valve group 322 according to the CDA gas consumption, the design flow of each air compressor and the data of the dew point analyzer 33.

[0040] Combination Figure 2 As shown, based on the gas supply system provided by the above basic implementation mode, this embodiment further provides a control method of the gas supply system, including:

[0041] According to the current CDA gas consumption V, it is determined whether the CDA air compressor station needs to be supplemented with gas by the nitrogen making system and whether the gas supplementation conditions of the nitrogen making system are met. If so, the first pressure regulating valve group 312 is opened and the nitrogen making system supplements gas to the CDA air compressor station through the first connecting pipeline 311. Otherwise, the CDA air compressor station supplies gas by itself. When the nitrogen making system supplements gas to the CDA air compressor station through the first connecting pipeline 311, the dew point data at the output end of the dryer 16 is monitored in real time to see whether it meets the standard. If it does not meet the standard, the second pressure regulating valve group 322 is opened and the first pressure regulating valve group 312 is closed, and the nitrogen making system supplements gas to the CDA air compressor station through the second connecting pipeline 321.

[0042] The gas supply system and control method provided in the above-mentioned embodiment, by setting two connecting pipelines between the nitrogen making system and the CDA air compressor station and matching the pressure regulating valve group, can supply gas from the nitrogen making system to the CDA air compressor station in a linked manner under different circumstances, realize interconnection and automatic adjustment under the premise of ensuring the stable operation of each air compressor, optimize the configuration of each air compressor to the maximum extent, reduce energy consumption, and prevent venting waste due to inconsistency between the design flow rate of the air compressor and the actual usage; moreover, the design flow rates of the CDA air compressor and the nitrogen making air compressor can be appropriately reduced to reduce investment costs.

[0043] Specifically, under normal air replenishment conditions, the CDA air compressor station selects the first connecting pipeline 311 to obtain compressed air from the nitrogen making system. The compressed air provided by the CDA air compressor 11 and the compressed air supplemented by the nitrogen making air compressor 21 are uniformly supplied to the required CDA after subsequent processing by the CDA air compressor station; when the CDA air compressor station experiences abnormal fluctuations and the CDA dew point does not meet the standard, the CDA air compressor station can obtain the process air (compressed dry gas mainly composed of nitrogen) treated by the nitrogen making system from the nitrogen making system through the second connecting pipeline 321 for use as CDA.

[0044] Continue to see Figure 1 In order to monitor in real time and perform auxiliary control, a first pressure sensor 351 is provided on the first connecting pipeline 311 for sensing the air pressure of the first connecting pipeline 311; in addition, a second pressure sensor 352 is provided at the output end of the dryer 16 for sensing the air pressure at the output end of the dryer 16.

[0045] Continue to see Figure 1 As a preferred embodiment, the CDA air compressor 11 includes a first CDA air compressor 111 and a second CDA air compressor 112; wherein the design flow rate W1 of the first CDA air compressor is the CDA gas consumption corresponding to the maximum production capacity of the production workshop, and the design flow rate W2 of the second CDA air compressor is the minimum CDA gas consumption to ensure uninterrupted gas supply to the key equipment in the production workshop. As an example: the first CDA air compressor 111 is a centrifugal air compressor, and the design flow rate W1 = 6000Nm 3 / h; the second CDA air compressor 112 is a screw air compressor with a design flow rate of W2 = 3000Nm 3 / h.

[0046] The above preferred embodiment further configures two CDA air compressors. When the CDA gas consumption is small, the second CDA air compressor 112 with a smaller design flow rate can be used to mainly supply gas, and the insufficient part can be supplemented by the nitrogen production system. In this way, the start-up rate and start-up time of the first CDA air compressor 111 with a larger design flow rate can be effectively reduced, thereby achieving further energy saving and consumption reduction, and ensuring comprehensive coverage of different stages of gas consumption.

[0047] Combination Figure 3 As shown, in the control method of the above-mentioned gas supply system, the specific control method of the nitrogen production system supplying gas to the CDA air compressor station through the first connecting pipeline 311 or the CDA air compressor station supplying gas by itself includes:

[0048] S1: configuring the CDA air compressor to be a first CDA air compressor 111 and a second CDA air compressor 112;

[0049] S2: Determine the interval of the current CDA gas consumption V. If V≧W1*70%, proceed to step S3A; if W1*70%>V≧W2, proceed to step S3B; if W2>V, proceed to step S3C;

[0050] S3A: Start the first CDA air compressor 111 to supply CDA air;

[0051] S3B: Start the second CDA air compressor 112 to supply CDA gas, and at the same time open the first pressure regulating valve group 312, and use the first connecting pipeline 311 to use the gas output from the nitrogen-generating air compressor 12 as a supplement to the CDA gas supply;

[0052] S3C: Start the second CDA air compressor 112 to supply CDA air.

[0053] As a preferred embodiment, in step S3A, the second CDA air compressor 112 is used as a backup, and the output air pressure at the output end of the dryer 16 is detected in real time; if the output air pressure is lower than the first preset threshold, the second CDA air compressor 112 is started to synchronously supply CDA gas; if the output air pressure is further lower than the second preset threshold, the first pressure regulating valve group 312 is opened, and the gas output by the nitrogen-making air compressor is used as a supplement to the CDA gas supply by using the first connecting pipeline 311; wherein the first preset threshold is greater than the second preset threshold. In addition, in step S3B and step S3C, the first CDA air compressor 111 is used as a backup, and the output air pressure at the output end of the dryer 16 is detected in real time; if the output air pressure is lower than the first preset threshold, the first CDA air compressor 111 is started to synchronously supply CDA gas.

[0054] The above preferred implementation scheme mainly takes into account that although the current CDA gas consumption V can be predicted based on the current production capacity, there are a few cases where sudden large-scale gas consumption will occur, such as the problem of instantaneous sudden supply shortage due to failure or other reasons. These temporary problems can be solved by the above backup plan.

[0055] Continue to see Figure 1 As a preferred embodiment, the nitrogen-making air compressor 21 includes a first nitrogen-making air compressor 211 and a second nitrogen-making air compressor 212; wherein, the design flow rate Q1 of the first nitrogen-making air compressor 211 is greater than the air volume S required for the maximum production capacity of the nitrogen-making system. The air volume S is a dynamic variable, and the air volume S of the nitrogen-making system refers to the volume of air passing through the nitrogen-making machine per unit time; preferably, the first nitrogen-making air compressor 211 is composed of two sub-air compressors; the design flow rate Q2 of the second nitrogen-making air compressor 212 is less than or equal to 50% of the design flow rate Q1 of the first nitrogen-making air compressor. As an example: the first nitrogen-making air compressor 211 is a centrifugal air compressor, and its design flow rate Q1 = 6600Nm 3 / h; the second nitrogen-generating air compressor 212 is a screw air compressor, and its design flow rate Q2 = 2500Nm 3 / h.

[0056] The above preferred embodiment further configures two or more nitrogen-making air compressors. Normally, the first nitrogen-making air compressor 211 with a larger design flow rate can be used to supply nitrogen-making air and replenish air for the CDA air compressor station. When the demand for nitrogen-making air and air replenishment for the CDA air compressor station is large, the second nitrogen-making air compressor 212 is turned on as an auxiliary to achieve more refined energy-saving control while ensuring comprehensive coverage of different stages of gas consumption.

[0057] Combination Figure 4 As shown, in the control method of the above-mentioned gas supply system, the gas replenishment conditions of the nitrogen making system and the specific control method of the nitrogen making system are met, including:

[0058] S10: configuring the nitrogen-generating air compressor to be a first nitrogen-generating air compressor 211 and a second nitrogen-generating air compressor 212;

[0059] S20: Determine the interval of the current CDA gas consumption V. If V+S≤Q1, proceed to step S30A; if Q1+Q2≥V+S≥Q1, proceed to step S30B; if V+S≥Q1+Q2, proceed to step S30C;

[0060] S30A: starting the first nitrogen-making air compressor to supply gas to the nitrogen-making system and opening the first pressure regulating valve group, using the first connecting pipeline to use the gas output by the first nitrogen-making air compressor as a supplement to the CDA gas supply;

[0061] S30B: starting the first nitrogen making air compressor and the second nitrogen making air compressor to supply gas to the nitrogen making system while opening the first pressure regulating valve group, and using the first connecting pipeline to use the gas output by the first nitrogen making air compressor as a supplement to the CDA gas supply;

[0062] S30C: The first nitrogen making air compressor and the second nitrogen making air compressor only supply air to the nitrogen making system.

[0063] Continue to see Figure 1 As a preferred embodiment, the gas supply system further includes a pressure-boosting and gas buffering component connected in parallel to the second connecting pipeline 321 downstream of the second pressure regulating valve group 322, for pressure-boosting and buffering the excess gas at the output end of the CDA air compressor station. Moreover, the pressure-boosting and gas buffering component is connected in parallel to the second connecting pipeline, which can not only pressure-boost and buffer the excess gas output by the dryer 16 itself, but also pressure-boost and buffer the excess gas transported to the output end of the dryer 16 by the nitrogen generation system through the second connecting pipeline 321.

[0064] Specifically, the boosting and gas buffer component includes a supercharger 41, a high-pressure buffer tank 42, a third pressure regulating valve group 43, a first three-way valve 91 and a second three-way valve 92; the inlet of the supercharger 41 is connected to the second connecting pipe 321 through the first three-way valve 91, the inlet of the high-pressure buffer tank 42 is connected to the outlet of the supercharger 41, the inlet of the third pressure regulating valve group 43 is connected to the outlet of the high-pressure buffer tank 42, and the outlet of the third pressure regulating valve group 43 is connected to the second connecting pipe 321 through the second three-way valve 92.

[0065] The working principle of the above-mentioned boosting and gas buffering components is: the excess gas at the output end of the CDA air compressor station is boosted by the booster 41, and then buffered in the high-pressure buffer tank 42. When the gas supply at the output end of the CDA air compressor station is insufficient, the high-pressure gas buffered in the high-pressure buffer tank 42 is released to the output end of the CDA air compressor station through the third pressure regulating valve group 43, so as to further balance the fluctuation at the output end of the CDA air compressor station. At the same time, the boosting and gas buffering components can play a temporary supplementary role for CDA when the dryer or air compressor fails.

[0066] Based on the boosting and gas buffer components described above, the control method of the above-mentioned gas supply system also includes: controlling the boosting and gas buffer components to boost and buffer the excess gas at the output end of the CDA air compressor station, and controlling the boosting and gas buffer components to release the buffered gas to the output end of the CDA air compressor station.

[0067] In this embodiment, the second pressure sensor 352 is arranged on the pipeline between the third pressure regulating valve group 43 and the second three-way valve; of course, the second pressure sensor 352 can also be arranged on the pipeline between the second three-way valve and the output end of the dryer 16, or arranged upstream or downstream of the dew point analyzer 33, as long as the corresponding air pressure at the output end of the dryer 16 can be detected.

[0068] Continue to see Figure 1 The gas supply system provided in this embodiment also includes an emergency pipeline 51 directly connecting the CDA air compressor 11 and the nitrogen making air compressor 21, and an emergency switch valve 52 is provided on the emergency pipeline 51. In addition, the CDA air compressor station is also provided with a first flow meter 61 at the rear end (downstream) of the fine filter 17; a second flow meter 62 is provided on the second connecting pipeline 321; a third flow meter 63 is provided at the output end of the nitrogen making system; and a CO2 analyzer 64 is also provided at the rear end (downstream) of the molecular sieve purification unit 23 of the nitrogen making system.

[0069] Figure 5The hardware architecture based on the control method of the air supply system provided in this embodiment is shown. In addition, the pressure sensor in this embodiment is equipped with two transmitters, and the average value of the measured value is used for adjustment. If one of them fails, the remaining transmitter can be directly referenced. If the deviation between any two transmitters is too large, all equipment units of the affected air network will be transferred to local control to protect the actual pressure in the air network.

[0070] The above disclosure is only the preferred embodiment of the present application, which certainly cannot be used to limit the scope of rights of the present application. Therefore, equivalent changes made according to the claims of the present application are still within the scope covered by the present application.

Claims

1. A gas supply system, comprising a CDA air compression station and a nitrogen production system, characterized in that: A first connecting pipeline is provided from the output end of the nitrogen making air compressor of the nitrogen making system to the output end of the CDA air compressor of the CDA air compressor station, and a first pressure regulating valve group is provided on the first connecting pipeline; a second connecting pipeline is provided from the output end of the molecular sieve purification unit of the nitrogen making system to the output end of the dryer of the CDA air compressor station, and a second pressure regulating valve group is provided on the second connecting pipeline; a dew point analyzer is provided on the output end of the dryer.

2. The gas supply system according to claim 1, characterized in that: The first connecting pipeline is provided with a first pressure sensor, and the output end of the dryer is provided with a second pressure sensor.

3. The gas supply system according to claim 1, characterized in that: The CDA air compressor includes a first CDA air compressor and a second CDA air compressor; the design flow of the first CDA air compressor is the CDA gas consumption corresponding to the maximum production capacity of the production workshop, and the design flow of the second CDA air compressor is the minimum CDA gas consumption to ensure uninterrupted gas supply to key equipment in the production workshop.

4. The gas supply system according to claim 1, characterized in that: The nitrogen-making air compressor includes a first nitrogen-making air compressor and a second nitrogen-making air compressor; the design flow rate of the first nitrogen-making air compressor is greater than the amount of air required corresponding to the maximum production capacity of the nitrogen-making system, and the design flow rate of the second nitrogen-making air compressor is less than or equal to 50% of the design flow rate of the first nitrogen-making air compressor.

5. The gas supply system according to any one of claims 1 to 4, characterized in that: The gas supply system further includes a pressure-boosting and gas buffering component connected in parallel to the second connecting pipeline downstream of the second pressure-regulating valve group.

6. The gas supply system according to claim 5, characterized in that: The boosting and gas buffer component includes a supercharger, a high-pressure buffer tank, a third pressure regulating valve group, a first three-way valve and a second three-way valve; the inlet of the supercharger is connected to the second connecting pipeline through the first three-way valve, the inlet of the high-pressure buffer tank is connected to the outlet of the supercharger, the inlet of the third pressure regulating valve group is connected to the outlet of the high-pressure buffer tank, and the outlet of the third pressure regulating valve group is connected to the second connecting pipeline through the second three-way valve.

7. A method for controlling an air supply system, characterized in that: Based on the gas supply system according to claim 1, the control method comprises: According to the current CDA gas consumption, it is judged whether the CDA air compressor station needs to be supplemented with gas by the nitrogen making system and whether the gas supplementation conditions of the nitrogen making system are met. If yes, the first pressure regulating valve group is opened and the nitrogen making system supplements gas to the CDA air compressor station through the first connecting pipeline. Otherwise, the CDA air compressor station supplies gas by itself. When the nitrogen making system supplies air to the CDA air compressor station through the first connecting pipeline, the dew point data at the output end of the dryer is monitored in real time to see whether it meets the standard. If it does not meet the standard, the second pressure regulating valve group is opened and the first pressure regulating valve group is closed, and the nitrogen making system supplies air to the CDA air compressor station through the second connecting pipeline.

8. The control method of the gas supply system according to claim 7, characterized in that: The specific control method of the nitrogen generation system supplying gas to the CDA air compressor station through the first connecting pipeline or the CDA air compressor station supplying gas by itself includes: S1: The CDA air compressor is configured as a first CDA air compressor and a second CDA air compressor; the design flow rate W1 of the first CDA air compressor is the CDA gas consumption corresponding to the maximum production capacity of the production workshop, and the design flow rate W2 of the second CDA air compressor is the minimum CDA gas consumption to ensure uninterrupted gas supply to key equipment in the production workshop; S2: Determine the interval of the current CDA gas consumption V. If V≧W1*70%, proceed to step S3A; if W1*70%>V≧W2, proceed to step S3B; if W2>V, proceed to step S3C; S3A: Start the first CDA air compressor to supply CDA air; S3B: starting the second CDA air compressor to supply CDA gas, and at the same time opening the first pressure regulating valve group, using the first connecting pipeline to use the gas output by the nitrogen-generating air compressor as a supplement to the CDA gas supply; S3C: Start the second CDA air compressor to supply CDA air.

9. The control method of the gas supply system according to claim 7, characterized in that: The specific control methods for meeting the air supply conditions of the nitrogen making system and the nitrogen making system include: S10: configuring the nitrogen-generating air compressor into a first nitrogen-generating air compressor and a second nitrogen-generating air compressor; the design flow rate Q1 of the first nitrogen-generating air compressor is greater than the air volume S required for the maximum capacity of the nitrogen-generating air compressor, and the design flow rate Q2 of the second nitrogen-generating air compressor is less than or equal to 50% of the design flow rate of the first nitrogen-generating air compressor; S20: Determine the interval of the current CDA gas consumption V. If V+S≤Q1, proceed to step S30A; if Q1+Q2≥V+S≥Q1, proceed to step S30B; if V+S≥Q1+Q2, proceed to step S30C; S30A: starting the first nitrogen-making air compressor to supply gas to the nitrogen-making system and opening the first pressure regulating valve group, using the first connecting pipeline to use the gas output by the first nitrogen-making air compressor as a supplement to the CDA gas supply; S30B: starting the first nitrogen making air compressor and the second nitrogen making air compressor to supply gas to the nitrogen making system while opening the first pressure regulating valve group, and using the first connecting pipeline to use the gas output by the first nitrogen making air compressor as a supplement to the CDA gas supply; S30C: The first nitrogen making air compressor and the second nitrogen making air compressor only supply air to the nitrogen making system.

10. The control method of the gas supply system according to any one of claims 7 to 9, characterized in that: Also includes: The CDA air compressor station is equipped with a boosting and gas buffer component, which controls the boosting and gas buffer component to boost and buffer the excess gas at the output end of the CDA air compressor station, and controls the boosting and gas buffer component to release the buffered gas to the output end of the CDA air compressor station.

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