Online process mass spectrometry sampling system integration device and online process mass spectrometry sampling method

Abstract

The application provides an online process mass spectrum sampling system integration device and an online process mass spectrum sampling method, and relates to the technical field of online process mass spectrum detection. The online process mass spectrum sampling system integration device comprises a shell, a gas non-discrimination flow regulation module integrated in the shell, a transmission module, a bypass anti-suction prevention and control module, a flow guide adjustment module, a vacuum auxiliary module and a control module. The control module is used for sending a control instruction to the gas non-discrimination flow regulation module to regulate the flow of the inflowing gas without discrimination; and sending a control instruction to the bypass anti-suction prevention and control module to identify whether there is a reverse suction trend in the flow path based on a flow path pressure difference signal, and cutting off the flow path when the reverse suction trend is identified. The online process mass spectrum sampling system integration device integrates gas non-discrimination, anti-suction prevention and control and flow regulation, effectively eliminates gas sampling discrimination, avoids sample cross-contamination, and improves sampling accuracy and detection efficiency.

Description

Technical Field

[0001] This invention relates to the field of online process mass spectrometry detection technology, and in particular to an integrated device for an online process mass spectrometry sample introduction system and an online process mass spectrometry sample introduction method. Background Technology

[0002] Online process mass spectrometers are core equipment in the field of industrial online monitoring, and their detection accuracy, response speed and stability directly depend on the performance of the sample introduction system.

[0003] Currently, online process mass spectrometry (MSS) injection systems exhibit certain mass discrimination. Different gases experience varying injection flow rates as they enter the system, leading to different injection volumes and consequently affecting the final measurement results. Furthermore, during sampling, switching between multiple flow paths and bypass flow design can easily cause backflow, resulting in air entrainment and inaccurate measurements. Additionally, fluctuations in sample pressure can cause changes in flow rate, leading to variations in the mass spectrometer injection volume and thus measurement errors.

[0004] Therefore, how to design an online process mass spectrometry injection system that can non-discriminatoryly control the injection flow rate, actively defend against the risk of backflow, and precisely adjust the injection flow rate in the mass spectrometry chamber is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] To address the technical problems of gas discrimination, backflow in the flow path, and low precision in controlling the injection flow rate in the mass spectrometry chamber in existing online process mass spectrometry injection systems, the present invention aims to provide an integrated device and method for an online process mass spectrometry injection system, which aims to achieve non-discriminatory control of the injection flow rate, proactive defense against backflow risk, and precise adjustment of the injection flow rate in the mass spectrometry chamber.

[0006] An integrated device for an online process mass spectrometry sample introduction system includes: case; A non-discriminatory gas flow control module is disposed inside the housing and is used to connect to a gas source and perform non-discriminatory flow control on the inflowing gas; The transmission module is located inside the housing, with its inlet end connected to the outlet end of the gas-discrimination-free flow control module and its outlet end connected to the mass spectrometry chamber. The bypass backflow prevention module is installed inside the housing. Its inlet end is connected to the outlet end of the gas-free flow control module and is connected in parallel with the inlet end of the transmission module. It is used to monitor whether there is a backflow trend in the flow path and to cut off the flow path when a backflow trend is detected. A flow conductance adjustment module is disposed inside the housing and located upstream of the outlet end of the transmission module. It is used to adjust the flow conductance of the gas entering the pre-vacuum pump pipeline, thereby controlling the gas flow rate entering the mass spectrometer chamber. The vacuum-assisted module includes a first-stage vacuum unit connected upstream of the outlet end of the transmission module and a second-stage vacuum unit connected to the mass spectrometry chamber; The control module is electrically connected to both the gas-discrimination-free flow control module and the bypass backflow prevention module. The control module is used for: Send a control command to the non-discriminatory flow control module to regulate the flow of the inflowing gas in a non-discriminatory manner; A control command is sent to the bypass backflow prevention module to identify whether there is a backflow trend in the flow path based on the flow path pressure difference signal, and to cut off the flow path when a backflow trend is identified.

[0007] Furthermore, the gas-discrimination-free flow control module includes: Pressure reducing valve, with its inlet connected to the gas source; The first fine-tuning valve has its inlet connected to the outlet of the pressure reducing valve, and its outlet connected to the inlet of the transmission module.

[0008] Furthermore, the transmission module includes: The first three-way valve has its inlet connected to the outlet of the first fine-tuning valve, and one of its outlets is connected to the inlet of the bypass back suction control module. The capillary tube's inlet end is connected to the other outlet of the first three-way valve; The second three-way valve has its inlet connected to the outlet end of the capillary, and one of its outlets connected to the inlet end of the flow conduction adjustment module. A flow-limiting microorifice is located at the other outlet of the second three-way valve and is connected to the mass spectrometry chamber.

[0009] Furthermore, the inlet and outlet ends of the capillary are detachably connected to the first three-way valve and the second three-way valve, respectively.

[0010] Furthermore, the anti-absorption control module includes: The second fine-tuning valve has its inlet connected to one of the outlets of the first three-way valve; A differential pressure acquisition unit is installed between the inlet and outlet of the second fine-tuning valve to acquire the differential pressure signal in the flow path and transmit it to the control module. The control module has a built-in flow identification unit, which calculates the real-time flow rate and judges the backflow trend based on the differential pressure-flow fitting equation. A vacuum solenoid valve, connected to the outlet of the second fine-tuning valve, is used to controllably cut off the flow path when a backflow tendency is detected.

[0011] Furthermore, the criteria for determining the reverse absorption trend are as follows: When the real-time flow rate calculated based on the pressure difference-flow rate fitting equation rapidly decreases from the forward injection flow rate to zero flow rate or a negative flow rate appears, it is determined that there is a reverse suction trend.

[0012] Furthermore, the flow regulation module includes a third fine-tuning valve, the inlet of which is connected to one of the outlets of the second three-way valve; The first-stage vacuum unit includes a first vacuum gauge and a pre-vacuum pump; the first vacuum gauge is located on the flow path between the inlet of the third fine-tuning valve and the outlet of the second three-way valve, and is used to monitor the flow path pressure so that the flow path pressure is controlled within the first-stage preset vacuum range; the pre-vacuum pump is connected to the third fine-tuning valve.

[0013] Furthermore, the second-stage vacuum unit includes a second vacuum gauge and a molecular pump; The second vacuum gauge is connected to the mass spectrometer chamber and is used to monitor the pressure inside the mass spectrometer chamber, so that the pressure inside the mass spectrometer chamber is controlled within the second-stage preset vacuum range; one end of the molecular pump is connected to the mass spectrometer chamber and the other end is connected to the fore-stage vacuum pump; Furthermore, the first-stage preset vacuum degree is ≤200Pa; The second-stage preset vacuum degree is ≤5×10 -6 torr.

[0014] On the other hand, the present invention also provides an online process mass spectrometry injection method, which uses the online process mass spectrometry injection system integration device described in any of the above embodiments, and includes the following steps: The vacuum assist module is activated, and the first-stage vacuum unit and the second-stage vacuum unit work together to establish and maintain the preset vacuum level in the flow path and mass spectrometry chamber. The gas source is injected without discrimination through a non-discriminatory gas flow control module; The bypass backflow prevention module monitors the backflow trend of the flow path in real time and cuts off the flow path when it is detected. The flow conductance adjustment module adjusts the flow conductance of the pre-vacuum pump pipeline, and the gas enters the mass spectrometry chamber through the transmission module.

[0015] Compared with the prior art, the online process mass spectrometry sample introduction system integrated device provided in the embodiments of the present invention has at least the following technical effects: The integrated online process mass spectrometry sample introduction system includes a housing, a non-discriminatory flow rate control module, a transmission module, a bypass backflow prevention module, a flow rate regulation module, a vacuum auxiliary module, and a control module. The non-discriminatory flow rate control module, transmission module, bypass backflow prevention module, and flow rate regulation module are all integrated within the same housing. The non-discriminatory flow rate control module connects to the gas source and regulates the inflow gas flow rate without discrimination. The inlet of the transmission module connects to the outlet of the non-discriminatory flow rate control module, and the outlet connects to the mass spectrometry chamber. The inlet of the bypass backflow prevention module connects to the outlet of the non-discriminatory flow rate control module and is connected in parallel with the inlet of the transmission module. It monitors the presence of backflow tendency in the flow path and cuts off the flow path when a backflow tendency is detected. The flow rate regulation module is located upstream of the outlet of the transmission module and regulates the flow rate of the fore-vacuum pump line, thereby controlling the gas flow rate entering the mass spectrometry chamber. The vacuum auxiliary module includes a first-stage vacuum unit connected upstream of the outlet of the transmission module and a second-stage vacuum unit connected to the mass spectrometry chamber. The control module is electrically connected to both the gas-discrimination-free flow control module and the bypass backflow prevention module. The control module sends control commands to the gas-discrimination-free flow control module to regulate the inflow gas flow without discrimination. It also sends control commands to the bypass backflow prevention module to identify the presence of backflow tendency based on the flow path pressure difference signal and cuts off the flow path when a backflow tendency is detected. This integrated online process mass spectrometry injection system highly integrates the gas-discrimination-free flow control module, transmission module, bypass backflow prevention module, and flow conductance adjustment module within a housing, and employs a control module for coordinated control. This solves the problems of dispersed functional modules and poor coordination in existing online process mass spectrometry injection systems. The gas-discrimination-free flow control module eliminates gas discrimination, ensuring the consistency of multi-component gas injection flow rates. The bypass backflow prevention module effectively avoids backflow, thus preventing sample cross-contamination. The flow conductance adjustment module regulates the flow conductance of the fore-vacuum pump pipeline, achieving quantitative and precise control of the mass spectrometry injection volume and effectively avoiding the impact of sample pressure fluctuations on the mass spectrometry injection volume. Therefore, this online process mass spectrometry sample introduction system integrates gas discrimination elimination, back-absorption control, and flow regulation, effectively eliminating gas introduction discrimination, avoiding sample cross-contamination, improving sample introduction accuracy and detection efficiency, and better adapting to the complex working conditions of industrial sites such as chemical and metallurgical industries.

[0016] The online process mass spectrometry injection method uses the online process mass spectrometry injection system integration device described in the above embodiments, and therefore possesses at least the technical effects of the online process mass spectrometry injection system integration device, which will not be elaborated further here. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the principle structure of an integrated device for an online process mass spectrometry sample introduction system in one embodiment of the present invention.

[0019] Reference numerals: 11, pressure reducing valve; 12, first fine-tuning valve; 21, first three-way valve; 22, capillary tube; 23, second three-way valve; 24, flow-limiting microorifice; 31, second fine-tuning valve; 32, differential pressure acquisition unit; 33, vacuum solenoid valve; 41, third fine-tuning valve; 51, first vacuum gauge; 52, fore-vacuum pump; 53, second vacuum gauge; 54, molecular pump; 60, mass spectrometer. Detailed Implementation

[0020] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly set on the other component; when a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to the other component.

[0022] It should be noted that the structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which this application can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size should still fall within the scope of the technical content disclosed in this application, provided that they do not affect the effects and purposes that this application can produce.

[0023] Please see the appendix Figure 1As shown, an embodiment of the present invention provides an integrated device for an online process mass spectrometry sample introduction system, including a housing, a non-discriminatory flow rate control module, a transmission module, a bypass back-absorption control module, a flow conductance adjustment module, a vacuum auxiliary module, and a control module. The non-discriminatory flow rate control module, transmission module, bypass back-absorption control module, and flow conductance adjustment module are all integrated within the same housing, resulting in a compact structure suitable for use in confined industrial environments. The non-discriminatory flow rate control module is used to connect to a gas source and perform non-discriminatory flow rate control on the incoming gas. "Non-discriminatory" means that during flow rate control, there is no selective transmission, component separation, or proportional distortion for gases of different types, molecular weights, viscosities, and adsorption characteristics; only the gas flow rate is changed without altering the original component ratio of the sample gas or standard gas. The inlet end of the transmission module is connected to the outlet end of the non-discriminatory flow rate control module, and the outlet end is connected to the mass spectrometry chamber 60. The outlet end of the transmission module is provided with a docking interface that matches the mass spectrometry chamber 60, and the docking interface can be designed appropriately according to the model of the mass spectrometer. The inlet of the bypass backflow prevention module is connected to the outlet of the non-discriminatory flow control module and is connected in parallel with the inlet of the transmission module. It is used to monitor for backflow tendencies in the flow path and to cut off the flow path when a backflow tendency is detected. The flow conductance adjustment module is located upstream of the outlet of the transmission module and is used to adjust the flow conductance of the pre-vacuum pump 52 pipeline, thereby controlling the gas flow rate entering the mass spectrometry chamber 60. The vacuum auxiliary module includes a first-stage vacuum unit connected upstream of the outlet of the transmission module and a second-stage vacuum unit connected to the mass spectrometry chamber 60. The control module is electrically connected to both the non-discriminatory flow control module and the bypass backflow prevention module. The control module sends control commands to the non-discriminatory flow control module to regulate the inflow gas flow rate without discrimination; it also sends control commands to the bypass backflow prevention module to identify the presence of a backflow tendency in the flow path based on the flow path pressure difference signal and cuts off the flow path when a backflow tendency is detected.

[0024] The online process mass spectrometry sample introduction system integrates a gas discrimination flow rate control module, a transmission module, a bypass backflow prevention module, a flow conductance adjustment module, a vacuum assistance module, and a control module, enabling them to work collaboratively and achieve stable and reliable control of the entire process from gas introduction to stable delivery into the mass spectrometry chamber 60. Its core working principle is as follows: under the unified scheduling of the control module, the sample gas is stably and faithfully transmitted through non-discriminatory flow rate control and sample flow conductance adjustment; simultaneously, the bypass backflow prevention module actively defends against backflow risks through real-time monitoring and backflow cutoff, thereby providing high-quality sample introduction conditions for mass spectrometry analysis.

[0025] In some optional embodiments, the gas-discrimination-free flow control module includes a pressure reducing valve 11 and a first fine-tuning valve 12. The inlet of the pressure reducing valve 11 is connected to a gas source. The inlet of the first fine-tuning valve 12 is connected to the outlet of the pressure reducing valve 11, and the outlet is connected to the inlet of the transmission module. Specifically, the inlet of the pressure reducing valve 11 is provided with a sample gas / standard gas interface (such as a quick connector) for connecting to a gas source (sample gas or standard gas), and the outlet of the pressure reducing valve 11 is connected to the inlet of the first fine-tuning valve 12 through a flow channel connector. The pressure reducing valve 11 is a precision pressure reducing valve, and the first fine-tuning valve 12 is a low-flow-conductivity precision needle valve. In this embodiment, through the combined application of the pressure reducing valve 11 and the first fine-tuning valve 12, the pressure reducing valve 11 first stabilizes the inlet pressure, and then the first fine-tuning valve 12 achieves flow regulation by means of pure fluid resistance throttling. The gas flow state is stable and does not depend on its physical properties, which can effectively avoid discrimination effects such as fractionation of light and heavy components and adsorption retention. Unlike conventional flow regulation methods that rely on gas thermophysical properties, density, or viscosity for measurement and control, this combination does not require calibration for a single gas. It can achieve continuous stepless and precise flow regulation over a wide range (5~500 sccm) while always maintaining the fidelity of gas composition, thus achieving gas-free flow regulation.

[0026] In some optional embodiments, the transmission module includes a first three-way valve 21, a capillary tube 22, a second three-way valve 23, and a flow-limiting microorifice 24. The inlet of the first three-way valve 21 is connected to the outlet of the first fine-tuning valve 12, and the inlet of the bypass backflow control module is connected to one of the outlets of the first three-way valve 21; the inlet of the capillary tube 22 is connected to the other outlet of the first three-way valve 21; the inlet of the second three-way valve 23 is connected to the outlet of the capillary tube 22, and the inlet of the flow conductance adjustment module is connected to one of the outlets of the second three-way valve 23; the flow-limiting microorifice 24 is located at the other outlet of the second three-way valve 23 and is connected to the mass spectrometry chamber 60. Different inner diameters of the flow-limiting microorifice 24 (e.g., 50 μm, 70 μm, 100 μm) can be replaced according to different detection scenarios. The thickness of the flow-limiting microorifice 24 is 700 μm. This embodiment achieves efficient and stable transmission of molecular flow and reduces the dead volume of the flow path through the synergy of the capillary tube 22 and the flow-limiting microorifice 24. In this context, molecular flow refers to the flow state where the mean free path of gas molecules is much larger than the channel size, representing the ideal flow state for mass spectrometry sample introduction. Dead volume is the cavity volume in the flow path that does not participate in effective gas transport; the smaller the dead volume, the weaker the sample memory effect and the faster the system response. The selection of the inner diameter of capillary 22 follows the principle of matching flow rate requirements with flow state. Larger inner diameter capillary 22 is suitable for high sample flow rate scenarios, reducing flow resistance and increasing gas throughput; smaller inner diameter capillary 22 is suitable for high-precision, low-flow rate scenarios, helping to constrain the flow state, suppress pressure disturbances, and reduce the memory effect. The inner diameter specification of capillary 22 is determined comprehensively based on the target molecular flow conditions and the upstream pressure. In this embodiment, through the combination of capillary 22 and flow-limiting microorifice 24, the capillary 22 achieves pressure gradient buffering and flow pre-stabilization through a slender flow channel, while the flow-limiting microorifice 24 serves as the flow-limiting core, used to establish stable molecular flow conditions. The combination of these two effectively avoids turbulence, pulsation, and component fractionation. Meanwhile, the overall flow channel adopts a slender, straight-through, and compact layout, and is equipped with a low dead volume sealing connector, which greatly compresses the cavity and stagnant space, thereby achieving efficient and stable molecular flow transmission and reducing the dead volume of the flow path.

[0027] In some optional embodiments, the inlet and outlet ends of the capillary 22 are detachably connected to the first three-way valve 21 and the second three-way valve 23, respectively. Specifically, the capillary 22 is detachably connected to the first three-way valve 21 and the second three-way valve 23 via threaded sealing connectors, which facilitates the replacement of capillary 22 with different inner diameters (e.g., 0.075mm, 0.1mm, 0.15mm) according to different detection scenarios (high flow rate or high precision).

[0028] In some optional embodiments, the backflow prevention module includes a second fine-tuning valve 31, a differential pressure acquisition unit 32, and a vacuum solenoid valve 33. The inlet of the second fine-tuning valve 31 is connected to one of the outlets of the first three-way valve 21. The differential pressure acquisition unit 32 is located between the inlet and outlet of the second fine-tuning valve 31 and is electrically connected to the control module. It is used to acquire the flow path differential pressure signal and transmit it to the control module. The control module has a built-in flow identification unit that calculates the real-time flow rate based on the differential pressure-flow rate fitting equation and determines the backflow trend. The vacuum solenoid valve 33 is connected to the outlet of the second fine-tuning valve 31 and is electrically connected to the control module. It is used to controllably cut off the flow path when a backflow trend is detected. The response time of the vacuum solenoid valve 33 is ≤0.5s. The differential pressure acquisition unit 32 is a differential pressure transmitter.

[0029] In some optional embodiments, the criterion for determining the backflow trend is: when the real-time flow rate calculated based on the differential pressure-flow rate fitting equation rapidly decreases from the forward injection flow rate to zero flow rate or a negative flow rate appears, it is determined that a backflow trend exists. Specifically, during normal injection, the vacuum solenoid valve 33 is in the on state. When the real-time flow rate calculated by the flow recognition unit based on the differential pressure-flow rate fitting equation rapidly decreases from the forward injection flow rate to zero flow rate or a negative flow rate appears, the control module immediately sends a control command to the vacuum solenoid valve 33, causing it to act within a response time ≤0.5s, cutting off the flow path, thereby blocking the backflow and avoiding sample cross-contamination.

[0030] In some optional embodiments, the flow conductance adjustment module includes a third fine-tuning valve 41, the inlet of which is connected to one of the outlets of the second three-way valve 23. The first-stage vacuum unit includes a first vacuum gauge 51 and a fore-vacuum pump 52. The first vacuum gauge 51 is a low vacuum gauge. The third fine-tuning valve 41 can be used, but is not limited to, for manually adjusting the flow conductance of the fore-vacuum pipeline, thereby controlling the molecular flow rate entering the mass spectrometry chamber 60. Specifically, the adjustment logic for manually adjusting the molecular flow rate entering the mass spectrometry chamber 60 is as follows: by manually adjusting the opening of the third fine-tuning valve 41, the flow conductance of the flow path is changed, thereby changing the effective pumping speed of the fore-vacuum pump 52 at the front end of the flow-limiting microorifice 24, causing the pressure measured by the first vacuum gauge 51, i.e., the pressure at the front end of the flow-limiting microorifice 24, to change accordingly, ultimately achieving control over the molecular flow rate entering the mass spectrometry chamber 60. This can be described as follows: Adjusting the opening of the third fine-tuning valve → changing the flow conductance → changing the effective pumping speed of the forestage vacuum pump → changing the pressure of the first vacuum gauge (pressure at the front end of the flow-limiting micro-orifice) → controlling the molecular flow rate entering the mass spectrometer chamber.

[0031] In some optional embodiments, the first-stage vacuum unit is used to realize vacuum extraction and monitoring of the flow path at the front end of the flow-limiting micro-orifice 24. Specifically, a first vacuum gauge 51 is disposed on the flow path between the inlet of the third fine-tuning valve 41 and the outlet of the second three-way valve 23 to monitor the flow path pressure and control the flow path pressure within the first-stage preset vacuum range; a pre-stage vacuum pump 52 is connected to the third fine-tuning valve 41 to extract gas and establish and maintain a rough vacuum environment.

[0032] It should be further explained that the second-stage vacuum unit is used to realize vacuum extraction and monitoring within the mass spectrometry chamber 60, including a second vacuum gauge 53 and a molecular pump 54. The second vacuum gauge 53 is connected to the mass spectrometry chamber 60 and is used to monitor the pressure within the mass spectrometry chamber 60, ensuring that the pressure within the mass spectrometry chamber 60 is controlled within the preset vacuum level range of the second stage. One end of the molecular pump 54 is connected to the mass spectrometry chamber 60, and the other end is connected to the pre-vacuum pump 52, used to establish and maintain the high vacuum environment required by the mass spectrometry chamber 60 based on the rough vacuum environment provided by the pre-vacuum pump 52. The second vacuum gauge 53 is a high vacuum gauge. The pre-vacuum pump 52 evacuates the flow path at the front end of the flow-limiting microorifice 24 to 10... 0 ~10 2 A rough vacuum environment on the order of Pa. The rough vacuum level under typical operating conditions, i.e., the first-stage preset vacuum level, is ≤200 Pa. Molecular pump 54, in conjunction with the forepump 52, evacuates the mass spectrometry chamber 60 to 10 Pa. -4 ~10 -6 A high vacuum environment on the order of Pa. The high vacuum level under typical operating conditions, i.e., the second-stage preset vacuum level ≤ 5 × 10⁻⁶. -6 The forepump 52 and the molecular pump 54 work together to create a progressively decreasing vacuum gradient along the sample introduction direction. The forepump 52 provides the necessary forepump vacuum conditions for the molecular pump 54 and controls the pressure in the flow path at the front end of the flow-limiting microorifice 24 via the flow conductance adjustment module. The molecular pump 54 establishes a high vacuum differential pressure drive at the rear end, allowing the sample gas to enter the mass spectrometer chamber 60 stably in the form of a molecular flow through the capillary 22 and the flow-limiting microorifice 24. This synergistic mechanism ensures the stability of the gas transport driving force and avoids flow pulsation and backflow phenomena caused by direct suction at the high vacuum end, thereby constructing a reasonably gradient and stably matched vacuum environment between the sample introduction path and the mass spectrometer chamber 60.

[0033] In some optional embodiments, the control module can be, but is not limited to, an industrial touch screen all-in-one machine. This machine is embedded in the housing surface and integrates a touch operation panel and a controller. Operators can input system target parameters via the touch operation panel, including the first-level preset vacuum degree, the second-level preset vacuum degree, the sample injection flow rate setpoint, and alarm thresholds for relevant components. The control module receives operating status signals from the differential pressure acquisition unit 32, the first vacuum gauge 51, the second vacuum gauge 53, each valve, and each pump based on the aforementioned set parameters. It then performs coordinated control of the non-discriminatory flow rate regulation module, the bypass backflow prevention module, and the flow conductance adjustment module, thereby achieving automated management of sample injection flow rate regulation, backflow protection, and fault alarms.

[0034] The working process and synergistic effects of the various modules of the online process mass spectrometry sample introduction system integrated device provided by this invention are as follows: Connect the integrated device to the mass spectrometry chamber 60 of the online process mass spectrometer via the mass spectrometry docking interface. Check the fixation and sealing of each module. Set various parameters via the touch operation panel (e.g., first-stage preset vacuum degree 200 Pa, second-stage preset vacuum degree (2.09±0.05)×10). -6 (Trr, injection flow rate setpoint 5-500 sccm). Start the pre-vacuum pump 52 of the vacuum assist module to perform rough vacuum extraction on the flow path at the front end of the flow-limiting micro-orifice 24 of the transmission module. The low vacuum gauge monitors the vacuum level in this area in real time. When the pressure reaches and stabilizes at the preset first-stage vacuum level, start the molecular pump 54 to begin high-vacuum extraction of the mass spectrometry chamber 60. The high vacuum gauge monitors the vacuum level inside the mass spectrometry chamber 60 in real time until the preset second-stage vacuum level is reached and stabilized.

[0035] Sample gas or standard gas enters the system through the sample gas / standard gas interface of the non-discriminatory flow control module. Specifically, the gas first passes through a precision pressure reducing valve, where the pressure is adjusted to 0.05-0.2 MPa. Subsequently, the gas flows through a low-conductivity precision needle valve, where the flow rate is adjusted to the range of the injection flow rate set value, achieving non-discriminatory injection. During the injection process, the differential pressure acquisition unit 32 in the bypass backflow prevention module collects the flow path differential pressure signal in real time. The flow recognition unit in the control module converts the differential pressure signal into a real-time flow rate value according to a preset differential pressure-flow rate fitting equation. If a backflow trend is detected, such as the flow rate being lower than 5 sccm or the flow rate change rate exceeding ±5% / s, the control module immediately sends a command to the vacuum solenoid valve 33, causing it to close within a very short time (≤0.5s), rapidly cutting off the flow path and effectively preventing sample cross-contamination and detection distortion caused by backflow. In addition, during the injection process, the low vacuum gauge collects the pressure of the flow path at the front end of the flow-limiting microorifice 24 in real time. By observing the pressure value at the front end of the flow-limiting microorifice 24 fed back by the low vacuum gauge, the opening of the third fine-tuning valve 41 is dynamically adjusted to change the flow conductance of the flow path, thereby changing the effective pumping speed of the forestage vacuum pump 52 at the front end of the flow-limiting microorifice 24, and thus controlling the molecular flow rate entering the mass spectrometry chamber 60. Through this adjustment, the molecular flow rate entering the mass spectrometry chamber 60 through the flow-limiting microorifice 24 can be actively controlled, adapting it to the detection requirements of different sample concentrations or different sensitivities, enhancing the applicability of the device.

[0036] In addition, one embodiment of the present invention provides an online process mass spectrometry injection method, which uses the online process mass spectrometry injection system integration device described in any of the above embodiments, and includes the following steps: S1. Start the vacuum auxiliary module. The first-stage vacuum unit and the second-stage vacuum unit work together to establish and maintain the preset vacuum level in the flow path and mass spectrometry chamber. S2. The gas source is injected without discrimination through the non-discriminatory gas flow control module; S3, the bypass back suction prevention module monitors the back suction trend of the flow path in real time and cuts off the flow path when it is detected; S4. The flow conductance adjustment module adjusts the flow conductance of the pre-vacuum pump pipeline, and the gas enters the mass spectrometry chamber through the transmission module.

[0037] The online process mass spectrometry injection system integration device and online process mass spectrometry injection method provided by the present invention have at least the following advantages: (1) High integration and compact structure: The gas discrimination flow control module, bypass back suction control module, flow conduction adjustment module and transmission module are highly integrated into the housing, which effectively solves the problems of scattered modules, complicated installation and large size in the existing technology, improves the structural compactness of the integrated device and is more suitable for the installation needs of narrow spaces in industrial sites.

[0038] (2) Improve detection accuracy and adapt to industrial needs: By integrating gas-free discrimination, back-suction control and flow regulation, gas injection discrimination is effectively eliminated, cross-contamination of samples is avoided, and the accuracy of injection and detection efficiency are improved, which can better adapt to the complex working conditions of chemical, metallurgical and other industrial sites.

[0039] (3) Good coordination and strong stability: The control module performs unified coordinated control of each functional module, avoiding problems such as parameter mismatch and signal interference.

[0040] (4) Strong versatility and wide adaptability: The design of the detachable capillary and flow conduction adjustment module enables the integrated device to flexibly adapt to the multi-component gas injection requirements of different detection scenarios, solving the problem of poor versatility of existing integrated devices.

[0041] The above description is merely an embodiment of the present invention. It should be noted that those skilled in the art can make improvements without departing from the inventive concept of the present invention, but these improvements all fall within the protection scope of the present invention.

Claims

1. An integrated device for an online process mass spectrometry sample introduction system, characterized in that, include: case; A non-discriminatory gas flow control module is disposed inside the housing and is used to connect to a gas source and perform non-discriminatory flow control on the inflowing gas; The transmission module is located inside the housing, with its inlet end connected to the outlet end of the gas-discrimination-free flow control module and its outlet end connected to the mass spectrometry chamber. The bypass backflow prevention module is installed inside the housing. Its inlet end is connected to the outlet end of the gas-free flow control module and is connected in parallel with the inlet end of the transmission module. It is used to monitor whether there is a backflow trend in the flow path and to cut off the flow path when a backflow trend is detected. A flow conductance adjustment module is disposed inside the housing and located upstream of the outlet end of the transmission module. It is used to adjust the flow conductance of the pre-vacuum pump pipeline, thereby controlling the gas flow rate entering the mass spectrometer chamber. The vacuum-assisted module includes a first-stage vacuum unit connected upstream of the outlet end of the transmission module and a second-stage vacuum unit connected to the mass spectrometry chamber; The control module is electrically connected to both the gas-discrimination-free flow control module and the bypass backflow prevention module. The control module is used for: Send a control command to the non-discriminatory flow control module to regulate the flow of the inflowing gas in a non-discriminatory manner; A control command is sent to the bypass backflow prevention module to identify whether there is a backflow trend in the flow path based on the flow path pressure difference signal, and to cut off the flow path when a backflow trend is identified; The gas-discrimination-free flow control module includes: a pressure reducing valve, the inlet of which is connected to the gas source; and a first fine-tuning valve, the inlet of which is connected to the outlet of the pressure reducing valve, and the outlet of which is connected to the inlet of the transmission module. The backflow prevention module includes: a second fine-tuning valve, the inlet of which is connected to one of the outlets of the first three-way valve; a differential pressure acquisition unit, located between the inlet and outlet of the second fine-tuning valve, for acquiring flow path differential pressure signals and transmitting them to the control module; the control module has a built-in flow recognition unit, which calculates the real-time flow rate and determines the backflow trend based on the differential pressure-flow rate fitting equation; and a vacuum solenoid valve, connected to the outlet of the second fine-tuning valve, for controlled cutoff of the flow path when a backflow trend is detected. The condition for determining the backflow trend is: when the real-time flow rate calculated based on the differential pressure-flow rate fitting equation rapidly decreases from the positive injection flow rate to zero flow rate or a negative flow rate appears, it is determined that a backflow trend exists.

2. The online process mass spectrometry sample introduction system integrated device according to claim 1, characterized in that, The transmission module includes: The first three-way valve has its inlet connected to the outlet of the first fine-tuning valve, and one of its outlets is connected to the inlet of the bypass back suction control module. The capillary tube's inlet end is connected to the other outlet of the first three-way valve; The second three-way valve has its inlet connected to the outlet end of the capillary, and one of its outlets connected to the inlet end of the flow conduction adjustment module. A flow-limiting microorifice is located at the other outlet of the second three-way valve and is connected to the mass spectrometry chamber.

3. The online process mass spectrometry sample introduction system integrated device according to claim 2, characterized in that, The inlet and outlet ends of the capillary are detachably connected to the first three-way valve and the second three-way valve, respectively.

4. The integrated device for online process mass spectrometry sample introduction system according to claim 2, characterized in that, The flow regulation module includes a third fine-tuning valve, the inlet of which is connected to one of the outlets of the second three-way valve; The first-stage vacuum unit includes a first vacuum gauge and a pre-vacuum pump; the first vacuum gauge is located on the flow path between the inlet of the third fine-tuning valve and the outlet of the second three-way valve, and is used to monitor the flow path pressure so that the flow path pressure is controlled within the first-stage preset vacuum range; the pre-vacuum pump is connected to the third fine-tuning valve.

5. The online process mass spectrometry sample introduction system integrated device according to claim 4, characterized in that, The second-stage vacuum unit includes a second vacuum gauge and a molecular pump; The second vacuum gauge is connected to the mass spectrometer chamber and is used to monitor the pressure inside the mass spectrometer chamber, so that the pressure inside the mass spectrometer chamber is controlled within the second-stage preset vacuum range; one end of the molecular pump is connected to the mass spectrometer chamber and the other end is connected to the fore-stage vacuum pump.

6. The online process mass spectrometry sample introduction system integration device according to claim 5, characterized in that, The first stage preset vacuum degree is ≤200Pa; The second-stage preset vacuum degree is ≤5×10 -6 torr.

7. An online process mass spectrometry injection method, characterized in that, Using the online process mass spectrometry sample introduction system integrated device according to any one of claims 1 to 6, the method includes the following steps: The vacuum assist module is activated, and the first-stage vacuum unit and the second-stage vacuum unit work together to establish and maintain the preset vacuum level in the flow path and mass spectrometry chamber. The gas source undergoes non-discriminatory flow regulation via a non-discriminatory gas flow regulation module. The bypass backflow prevention module monitors the backflow trend of the flow path in real time and cuts off the flow path when it is detected. The flow conductance adjustment module adjusts the flow conductance of the pre-vacuum pump pipeline, and the gas enters the mass spectrometry chamber through the transmission module.

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