Multi-flow-path process gas online analysis and pretreatment device
The combined design of a two-position three-way valve and a multi-channel switching valve solves the problems of high failure rate and high equipment cost of multi-channel online analysis systems, achieves efficient and accurate gas detection, and adapts to the needs of high-pressure gas analysis.
Patent Information
- Application Number
- PCT/CN2024/083336
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-11-29
- Filing Date
- 2024-03-22
- Publication Date
- 2025-10-02
AI Technical Summary
The existing multi-stream automatic switching online analysis system has high failure rate and pipeline dead volume problems, and the equipment cost of the existing process gas online analysis pretreatment system is high and cannot be effectively reduced.
The combined design of a two-position three-way valve and a multi-channel switching valve simplifies the gas path structure. The two-stage pressure reducing valve and the multi-channel switching valve are used to solve the dead volume problem in the pipeline. The automatic switching and detection of gas flow direction are achieved through the PLC controller, reducing equipment costs.
It reduces equipment failure rate, simplifies gas path structure, improves detection accuracy and efficiency, adapts to high-pressure gas detection needs, and reduces equipment costs.
Smart Images

Figure CN2024083336_02102025_PF_FP_ABST
Abstract
Description
A multi-flow process gas online analysis pretreatment device Technical Field
[0001] The utility model belongs to the technical field of gas analysis, and in particular relates to a multi-flow process gas online analysis pretreatment device. Background Art
[0002] Chemical production processes involve complex material transformations and reactions, requiring real-time monitoring and control of various parameters. Online analysis provides real-time access to key production process indicators. With this real-time data, operators can promptly adjust operating conditions, optimize the production process, and ensure product quality and economic benefits. However, industrial production processes inherently involve numerous uncertainties and nonlinear factors: chemical and physical changes often occur during production; some processes have extremely demanding process conditions or environments, such as high temperatures, low temperatures, high pressures, and high dust levels; and sometimes even involve flammable, explosive, corrosive, or toxic materials, necessitating high safety requirements. Therefore, pretreatment of gas samples plays a crucial role in online analysis, effectively protecting back-end analytical instruments and extending their service life.
[0003] In the prior art, a multi-channel automatic switching online analysis system includes a sample channel, a purge inlet pipe, a standard gas tank, a pressure reducing valve, and a filter. At least two groups of sample channels are connected in parallel through a three-way valve. A purge inlet pipe is provided between each sample channel and the three-way valve. The top three-way valve is connected to the pressure reducing valve and the filter in sequence through a pipeline. The pipeline between the pressure reducing valve and the filter is connected to the standard gas tank through a three-way selection valve. The filter is connected to the sample inlet of the chromatograph. It can automatically and quickly switch multiple samples at the same time, and a purge gas source is configured when switching between each sample channel. Its disadvantages are:
[0004] 1. When each layer of flow path is sampling, the "three-way solenoid valves" of other layers of flow paths must all be moved to the corresponding valve position. Once one of the "three-way solenoid valves" fails, the system will not be able to operate normally. The more flow paths there are, the higher the failure rate.
[0005] 2. There are "dead volume" problems in the pipelines between the two ball valves on the pipeline between the flow sample and the sweep air inlet pipe, and in the pipelines between the "ball valve" and the "three-way solenoid valve".
[0006] The prior art also discloses a process gas online analysis pretreatment system, which includes at least one air intake line, at least one group of air intake main valves, a first-stage pressure reducing valve, an impurity filter, a second-stage pressure reducing valve, a three-way filter, an adjustable flow meter-branch, a branch check valve, an unloading valve, an automatic drain valve, a total discharge pressure gauge, a multi-channel switching valve, a three-way reversing valve, an adjustable flow meter-main line, a main line check valve, an adjustable flow meter-instrument, a PLC controller, and a control computer. This utility model can timely understand the pressure in the pipe, which is convenient for maintenance and troubleshooting; it solves the "dead volume" problem of the pipeline during gas line replacement and ensures the accuracy of gas detection; it can adapt to the detection needs of various high-pressure process gases and eliminate the influence of the main line intake pressure fluctuation on the detection results; it can avoid the formation of condensate in the process gas in the total exhaust pipe, thereby causing the pipeline "liquid seal" and causing exhaust blockage. Its disadvantages are:
[0007] For the gas material pipelines that need to be tested, each air inlet pipeline is equipped with a separate set of pretreatment equipment. As the number of test gas lines increases, the number of pretreatment pipe fittings and equipment increases, resulting in higher equipment costs.
[0008] Utility Model Content
[0009] In order to overcome the defects of the prior art, a multi-flow process gas online analysis pretreatment device is provided, which includes at least two air intake paths, an air intake main valve and a two-position three-way valve, and also includes a main exhaust pipe, a multi-channel switching valve, a first-stage pressure reducing valve, an impurity filter, a second-stage pressure reducing valve, a three-way filter, an adjustable flow meter, a standard gas intake valve, a PLC controller and a control computer, wherein:
[0010] The air intake circuit, the air intake main valve and the two-position three-way valve are connected in sequence, and the air intake main valve controls the opening and closing of the air intake circuit;
[0011] The two-position three-way valve switches the gas flow direction, switching between the connection between the main exhaust pipe and the intake air path and the connection between the detection and sampling main air path and the intake air path. The detection and sampling main air path includes a multi-channel switching valve, a first-level pressure reducing valve, an impurity filter, a second-level pressure reducing valve, a three-way filter and an adjustable flow meter connected in sequence;
[0012] The multi-channel switching valve switches between different air inlet paths and the detection and sampling main air path according to different requirements;
[0013] The first-stage pressure reducing valve adjusts the pressure of the test sample gas and reduces the pressure of the gas whose pressure is higher than the preset value;
[0014] The impurity filter removes mechanical impurities in the gas to be tested;
[0015] The secondary pressure reducing valve performs secondary pressure regulation on the gas after being decompressed by the primary pressure reducing valve, and its accuracy is higher than that of the primary pressure reducing valve;
[0016] The three-way filter removes mechanical impurities, water vapor and oil hydrocarbons in the gas to be tested, preventing impurities from entering key equipment or components;
[0017] The adjustable flow meter is a measuring instrument for measuring gas flow, which adjusts the flow of the gas to be measured and displays real-time flow data;
[0018] The standard gas inlet valve controls the opening and closing of the standard gas inlet path;
[0019] The I / O signal input point of the PLC controller is connected to the control computer, and the I / O signal output point is connected to the circuit control part of the two-position three-way valve, the multi-channel switching valve and the standard gas inlet valve.
[0020] Preferably, the main air intake valve is a butterfly valve, a ball valve, a needle valve or a stop valve.
[0021] Preferably, the two-position three-way valve is of electromagnetic drive type or gas drive type.
[0022] Preferably, the multi-channel switching valve is electromagnetically driven or gas driven.
[0023] Preferably, the primary pressure reducing valve is a lever-type pressure reducing valve, a diaphragm-type pressure reducing valve, a piston-type pressure reducing valve or a bellows-type pressure reducing valve.
[0024] Preferably, the impurity filter is a mesh filter, a sintered metal filter or a magnetic filter.
[0025] Preferably, the secondary pressure reducing valve is a film pressure reducing valve, a piston pressure reducing valve or a bellows pressure reducing valve.
[0026] Preferably, the filter element of the three-way filter is a sintered core, an activated carbon core, a PP cotton filter element, a ceramic core or a polypropylene fiber filter element.
[0027] Preferably, the adjustable flowmeter is a differential pressure flowmeter, a rotor flowmeter or a throttling flowmeter.
[0028] Preferably, the standard gas inlet valve is a butterfly valve, a ball valve, a needle valve or a stop valve.
[0029] Compared with the prior art, the present invention has at least the following beneficial effects:
[0030] (1) The air inlet adopts a two-position three-way valve to switch the flow direction of the process gas. The process gas of each gas path uses the same set of pretreatment devices located on the main gas path of the detection and sampling, which simplifies the pipes and valves and reduces the overall cost of the equipment;
[0031] (2) Using one main detection gas line, multiple pre-processing units are simplified into one set, reducing the number of connection points on each pipeline and lowering the failure rate;
[0032] (3) The two-position three-way valve keeps ports A and B connected, and the process gas is discharged to the main exhaust pipe through the two-position three-way valve on the air inlet line, shortening the distance from the gas material to the rear-end instrument and reducing the replacement time;
[0033] (4) The problem of “dead volume” in the pipeline during the gas replacement process is solved by using a multi-channel switching valve and a two-position three-way valve in combination, thus ensuring the accuracy of gas detection;
[0034] (5) The two-stage pressure reducing valve design adopted in the main gas line can not only meet the detection requirements of various high-pressure process gases, but also eliminate the influence of the main pipeline inlet pressure fluctuation on the detection results. BRIEF DESCRIPTION OF THE DRAWINGS
[0035] FIG1 is a schematic structural diagram of a multi-flow path process gas online analysis pretreatment device according to a specific embodiment of the present invention;
[0036] FIG2 is a schematic diagram of the flow paths of a multi-channel switching valve of a multi-channel process gas online analysis pretreatment device according to a specific embodiment of the present invention;
[0037] FIG3 is a schematic diagram of the control logic of the multi-flow path process gas online analysis pretreatment device according to a specific embodiment of the present invention.
[0038] Among them, 1, 2, 3, 4, 5, and 6 are the air intake paths; 101, 201, 301, 401, 501, and 601 are the main air intake valves; 102, 202, 302, 402, 502, and 602 are two-position three-way valves; 01 is the main exhaust pipe; 02 is the multi-channel switching valve; 03 is the first-stage pressure reducing valve; 04 is the impurity filter; 05 is the second-stage pressure reducing valve; 06 is the three-way filter; 07 is the adjustable flow meter; 08 is the standard gas intake valve; 7 is the standard gas intake path; 8 is the instrument gas path; 09 is the PLC controller; and 10 is the control computer. DETAILED DESCRIPTION
[0039] To facilitate understanding of the present invention, a more comprehensive description of the present invention will be provided below with reference to the accompanying drawings. The drawings illustrate preferred embodiments of the present invention. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to facilitate a more thorough and comprehensive understanding of the disclosure of the present invention.
[0040] Referring to Figure 1, this embodiment discloses a multi-flow process gas online analysis pretreatment device, which has 6 flow paths, including air inlet paths 1, 2, 3, 4, 5, and 6; air path air inlet main valves 101, 201, 301, 401, 501, and 601; two-position three-way valves 102, 202, 302, 402, 502, and 602; a main exhaust pipe 01; a multi-channel switching valve 02; a first-stage pressure reducing valve 03; an impurity filter 04; a second-stage pressure reducing valve 05; a three-way filter 06; an adjustable flow meter 07; a standard gas inlet valve 08; a standard gas inlet path 7; an instrument gas path 8; a PLC controller 09; and a control computer 10.
[0041] In a specific embodiment, the process gas online analysis pretreatment device includes: air inlet paths 1, 2, 3, 4, 5, and 6; connected to one end of the air inlet main valves 101, 201, 301, 401, 501, and 601; the other end of the air inlet main valves 101, 201, 301, 401, 501, and 601 is connected to the A port of the two-position three-way valves 102, 202, 302, 402, 502, and 602; the B port of the two-position three-way valves 102, 202, 302, 402, 502, and 602 is connected to the main exhaust pipe 01; the C port of the two-position three-way valves 102, 202, 302, 402, 502, and 602 is connected to the C port of the multi-channel switching valve 02 respectively. Port A, port B, port C, port D, port E, and port F are connected, port G of the multi-way switching valve 02 is connected to one end of the first-stage pressure reducing valve 03, the other end of the first-stage pressure reducing valve 03 is connected to one end of the impurity filter 04, the other end of the impurity filter 04 is connected to one end of the second-stage pressure reducing valve 05, the other end of the second-stage pressure reducing valve 05 is connected to the three-way filter 06, the other end of the three-way filter 06 is connected to the adjustable flowmeter 07, the other end of the adjustable flowmeter 07 is connected to the port of the instrument gas circuit 8, one end of the standard gas inlet valve 08 is connected to the port of the standard gas inlet gas circuit 7, and the other end of the standard gas inlet valve 08 is connected to the port of the instrument gas circuit 8.
[0042] The two-position three-way valves 102, 202, 302, 402, 502, and 602 control the switching between the intake air paths 1, 2, 3, 4, 5, and 6 and the main exhaust pipe 01 and the multi-channel switching valve 02. See Figure 2. The multi-channel switching valve 02 is a six-inlet and one-outlet switching valve, which respectively controls the connection switching between the intake air paths 1, 2, 3, 4, 5, and 6 and the first-stage pressure reducing valve 03.
[0043] The I / O control signal port of the PLC controller 09 is connected to the control ports of the two-position three-way valves 102, 202, 302, 402, 502, and 602 and the multi-channel switching valve 02. More preferably, the I / O control signal port of the PLC controller 09 is connected to the I / O control signal port of the analytical instrument. The host computer control software deployed on the control computer 10 sends instructions to the PLC controller 09, and the PLC controller 09 completes the control processes such as the switching of the intake gas paths 1, 2, 3, 4, 5, and 6, the gas replacement time control, and the detection and analysis. In addition, the PLC controller 09 can receive the status signal sent by the I / O control signal port of the analytical instrument and convert it into a digital signal that can be recognized by the control computer 10, which is then passed to the host computer control software for judgment and used as the operation parameter of the control instruction.
[0044] FIG3 is a control logic diagram of a process gas online analysis pretreatment device according to the present invention.
[0045] In the specific embodiment, in the initial state of operation of the above-mentioned device, the main inlet valve of the gas circuit to be analyzed is normally open, and the two-position three-way valve has ports A and B connected. The sample gas to be tested passes through the main inlet valve and the two-position three-way valve in sequence before entering the main exhaust pipe O1, forming a real-time and continuous replacement of the incoming sample gas, ensuring timely back-end feeding and ensuring the technical quality and accuracy of the analysis.
[0046] In the initial state of the above-described device, the two-position, three-way valve 03 is open to ports A and B, and the multi-way switching valve 02 can be in any state. The PLC controller 09 monitors the status signal from the analytical instrument. When the status signal indicates "ready," the PLC controller 09 reports the instrument-ready signal to the control computer 10. Based on the analysis requirements manually set in the host computer control software, the control computer 10 sends a switching signal to the PLC controller 09. The PLC controller 09 then controls the two-position, three-way valve to switch ports A and C, and the multi-way switching valve 02 to switch the corresponding inlet gas path. At this point, the sample gas to be tested passes through the gas path inlet main valve, the two-position, three-way valve, the multi-way switching valve 02, the first-stage pressure reducing valve 03, the impurity filter 04, the second-stage pressure reducing valve 05, the three-way filter 06, and the adjustable flowmeter 07, before finally entering the instrument gas path 8. After passing through the first-stage pressure reducing valve 03, the high-pressure sample gas is reduced to the adjustable range of the second-stage pressure reducing valve 05, which can meet the testing requirements of various high-pressure process gases. The impurity filter 04 is arranged before the secondary pressure reducing valve 05 to ensure that the rear-end precision instruments are not damaged by mechanical impurity particles.
[0047] After the analyzer completes its analysis of the sample gas, the instrument-ready signal is transmitted again via the PLC controller 09 to the control computer 10. The control computer 10 then performs the next round of control based on the analysis requirements manually set in the host computer control software. This control logic repeats itself, allowing a single analyzer to monitor multiple gas paths. This effectively improves the timeliness of monitoring data and reduces errors caused by manual sampling, transportation, and analysis. The analysis data is timely and reliable, reducing the cost of process gas analysis and improving efficiency.
[0048] The above embodiments are only intended to help understand the method and core concept of the present invention. It should be noted that those skilled in the art can make various improvements and modifications to the present invention without departing from the principles of the present invention, and such improvements and modifications also fall within the scope of protection of the claims of the present invention.
[0049] The above description of the disclosed embodiments will enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A multi-channel process gas online analysis pretreatment device, characterized in that: It includes at least two air intake paths, an air intake main valve and a two-position three-way valve, as well as a main exhaust pipe, a multi-channel switching valve, a first-stage pressure reducing valve, an impurity filter, a second-stage pressure reducing valve, a three-way filter, an adjustable flow meter, a standard gas intake valve, a PLC controller and a control computer, among which, The air intake circuit, the air intake main valve and the two-position three-way valve are connected in sequence, and the air intake main valve controls the opening and closing of the air intake circuit; The two-position three-way valve switches the gas flow direction, switching between the connection between the main exhaust pipe and the intake air path and the connection between the detection and sampling main air path and the intake air path. The detection and sampling main air path includes a multi-channel switching valve, a first-level pressure reducing valve, an impurity filter, a second-level pressure reducing valve, a three-way filter and an adjustable flow meter connected in sequence; The multi-channel switching valve switches between different air inlet paths and the detection and sampling main air path according to different requirements; The first-stage pressure reducing valve adjusts the pressure of the test sample gas and reduces the pressure of the gas whose pressure is higher than the preset value; The impurity filter removes mechanical impurities in the gas to be tested; The secondary pressure reducing valve performs secondary pressure regulation on the gas after being decompressed by the primary pressure reducing valve, and its accuracy is higher than that of the primary pressure reducing valve; The three-way filter removes mechanical impurities, water vapor and oil hydrocarbons in the gas to be tested, preventing impurities from entering key equipment or components; The adjustable flow meter is a measuring instrument for measuring gas flow, which adjusts the flow of the gas to be measured and displays real-time flow data; The standard gas inlet valve controls the opening and closing of the standard gas inlet path; The I / O signal input point of the PLC controller is connected to the control computer, and the I / O signal output point is connected to the circuit control part of the two-position three-way valve, the multi-channel switching valve and the standard gas inlet valve.
2. The multi-channel process gas online analysis pretreatment device according to claim 1, characterized in that: The main air intake valve is a butterfly valve, a ball valve, a needle valve or a stop valve.
3. The multi-channel process gas online analysis pretreatment device according to claim 1, characterized in that: The two-position three-way valve is of electromagnetic drive type or gas drive type.
4. The multi-channel process gas online analysis pretreatment device according to claim 1, characterized in that: The multi-channel switching valve is of electromagnetic drive type or gas drive type.
5. The multi-channel process gas online analysis pretreatment device according to claim 1, characterized in that: The primary pressure reducing valve is a lever type pressure reducing valve, a film type pressure reducing valve, a piston type pressure reducing valve or a bellows type pressure reducing valve.
6. The multi-channel process gas online analysis pretreatment device according to claim 1, characterized in that: The impurity filter is a mesh filter, a sintered metal filter or a magnetic filter.
7. The multi-channel process gas online analysis pretreatment device according to claim 1, characterized in that: The secondary pressure reducing valve is a film pressure reducing valve, a piston pressure reducing valve or a bellows pressure reducing valve.
8. The multi-channel process gas online analysis pretreatment device according to claim 1, characterized in that: The filter element of the three-way filter is a sintered core, an activated carbon core, a PP cotton filter element, a ceramic core or a polypropylene fiber filter element.
9. The multi-channel process gas online analysis pretreatment device according to claim 1, characterized in that: The adjustable flow meter is a differential pressure flow meter, a rotor flow meter or a throttling flow meter.
10. The multi-channel process gas online analysis pretreatment device according to claim 1, characterized in that: The standard gas inlet valve is a butterfly valve, a ball valve, a needle valve or a stop valve.