Automated Sample Introduction System for Gas Impurity Analysis

Abstract

An automated sample introduction system for gas impurity analysis includes multiple pneumatic valves, multiple tubing groups, multiple solenoid valves, and a control unit. The first, second, and fourth pneumatic valves are connected to a clean gas source, a current-carrying gas source, and a analyte gas source, respectively. The first tubing group connects the first to third pneumatic valves. The second tubing group connects the third and fourth pneumatic valves to the instrument's input port. The fifth pneumatic valve connects to the inlet of a vacuum pump. The third tubing group connects the fifth and sixth pneumatic valves to the instrument's output port. The seventh pneumatic valve connects to the exhaust port of the vacuum pump. The fourth tubing group connects the sixth and seventh pneumatic valves. The multiple solenoid valves are connected to a driving gas source. The driving gas interfaces of the first to seventh pneumatic valves are respectively connected to the multiple solenoid valves. The control unit is electrically connected to the control contacts of the multiple solenoid valves to control the opening and closing states of each pneumatic valve through the solenoid valves.

Description

[Technical Field]

[0001] This invention relates to a sample introduction system, and more particularly to an automated sample introduction system for the analysis of gas impurities. [Previous Technology]

[0002] A gas analyzer is an instrument that provides the function of analyzing gas components and can perform gas impurity analysis. When a gas sample is fed into the gas analyzer (sample injection), the operator connects a gas interface of the gas analyzer to a tubing and a gas valve, and then connects the tubing to a gas cylinder containing the gas to be tested. In this way, the operator can manually adjust the gas valve to inject an appropriate amount of the gas sample into the internal detection device of the gas analyzer for analysis. However, the aforementioned manual sample injection operation is prone to human error, and impurities in the tubing can easily contaminate the gas to be tested, thereby reducing the accuracy and efficiency of gas analysis. [Summary of the Invention]

[0003] In view of this, the main objective of the present invention is to provide an automated sample introduction system for gas impurity analysis, in order to overcome the problem of reduced accuracy and efficiency of gas analysis due to human factors as described in the prior art.

[0004] The automatic sample introduction system for gas impurity analysis of the present invention comprises: a first pneumatic valve connected to a clean gas source; a second pneumatic valve connected to a current-carrying gas source; a third pneumatic valve; a first pipeline group connecting the first pneumatic valve, the second pneumatic valve, and the third pneumatic valve; a fourth pneumatic valve connected to a gas source to be tested; a second pipeline group connecting the third pneumatic valve, the fourth pneumatic valve, and an input port of an instrument; a fifth pneumatic valve connected to an inlet of a vacuum pump; a sixth pneumatic valve; a third pipeline group connecting the fifth pneumatic valve, the sixth pneumatic valve, and an output port of the instrument; a seventh pneumatic valve connected to an exhaust port of the vacuum pump; and a fourth pipeline group connecting the sixth pneumatic valve and the seventh pneumatic valve. A plurality of solenoid valves are connected to a drive gas source, and the drive gas interfaces of the first to the seventh pneumatic valves are respectively connected to the plurality of solenoid valves; and a control unit is electrically connected to the control contacts of the plurality of solenoid valves. The control unit individually controls the valve opening or closing state of the plurality of solenoid valves, so that the drive gas source can individually drive the valves of the first to the seventh pneumatic valves to open or close.

[0005] The automatic sample introduction system for gas impurity analysis of the present invention can be connected between an instrument and various gas sources. Based on the physical principles of gas pressure and airflow and the desired automatic control purpose, relevant parameters and valve actuation schedules can be set for the control unit. This allows the control unit to control the opening or closing state of each pneumatic valve through each solenoid valve, thereby realizing automatic control functions such as cleaning, maintenance and sample introduction of the pipeline assembly. Therefore, the present invention can significantly reduce human operation factors, avoid human operation errors, and allow the gas to be tested to enter the instrument for analysis through a clean pipeline environment, effectively improving the accuracy and efficiency of gas analysis.

Implementation Method

[0007] The automatic sample introduction system for gas impurity analysis of the present invention can be applied to an instrument, which includes an input port, an output port, and an internal detection device connecting the input port and the output port. Gas can enter the internal detection device of the instrument through the input port and finally exit from the output port. The instrument provides gas composition analysis function and can perform gas impurity analysis. The instrument can be, for example, a gas chromatography instrument, which provides a chromatographic technique for separating and analyzing mixtures that are easily volatile and do not decompose in organic chemistry. However, the instrument used in the present invention is not limited to a gas chromatography instrument.

[0008] Referring to Figures 1 and 2, one embodiment of the automated sample introduction system for gas impurity analysis of the present invention includes a first pneumatic valve 11, a second pneumatic valve 12, a third pneumatic valve 13, a fourth pneumatic valve 14, a fifth pneumatic valve 15, a sixth pneumatic valve 16, a seventh pneumatic valve 17, a first pipeline group 21, a second pipeline group 22, a third pipeline group 23, a fourth pipeline group 24, a plurality of solenoid valves 40, and a control unit 50, or in another embodiment, a fifth pneumatic valve 18. It should be noted that the pipeline configuration disclosed in Figures 1 and 2 is for reference only regarding the gas flow direction. The first to seventh pneumatic valves 11-17, or the further included eighth pneumatic valve 18, can be integrated onto a base to form a modular device for easy portability and use.

[0009] The first pneumatic valve 11 is connected to a clean gas source G_clean, the second pneumatic valve 12 is connected to a carrier gas source G_carrier, and the eighth pneumatic valve 18 is connected to a calibration gas source G_standard. In one embodiment, each of the aforementioned gas sources can be a high-pressure gas container, which can be a gas cylinder. For example, the clean gas source G_clean can be a high-purity nitrogen (PN2) cylinder, the carrier gas source G_carrier can be a helium (He) cylinder, and the calibration gas source G_standard can be a standard gas (STD) cylinder. The high-purity nitrogen can be used to clean the pipeline, the helium can be used as the carrier gas, and the standard gas can be used to calibrate the instrument 60. The type of standard gas depends mainly on the model of the instrument 60.

[0010] The fourth pneumatic valve 14 is connected to a gas source G_test to be tested. The gas source G_test can be a high-pressure gas container containing the gas to be tested, and the high-pressure gas container can be a gas cylinder.

[0011] The first pipeline assembly 21 is connected to the first pneumatic valve 11, the second pneumatic valve 12 and the third pneumatic valve 13, or further connected to the eighth pneumatic valve 18. The first pneumatic valve 11 can control the connection or disconnection state between the clean air source G_clean and the first pipeline assembly 21. The second pneumatic valve 12 can control the connection or disconnection state between the current-carrying air source G_carrier and the first pipeline assembly 21. The eighth pneumatic valve 18 can control the connection or disconnection state between the calibration air source G_standard and the first pipeline assembly 21.

[0012] The second pipeline assembly 22 connects the third pneumatic valve 13, the fourth pneumatic valve 14, and the input port 61 of the instrument 60. The third pneumatic valve 13 can control the connection or disconnection between the first pipeline assembly 21 and the second pipeline assembly 22, and the fourth pneumatic valve 14 can control the connection or disconnection between the gas source G_test and the second pipeline assembly 22. The second pipeline assembly 22 may be equipped with a pressure measuring unit 220, which can measure the pipeline pressure of the second pipeline assembly 22 and output a corresponding pressure measuring signal Sp (unit: pound per square inch, psi). The second pipeline assembly 22 may be equipped with a filter 221 and / or a pressure reducing valve 222. The filter 221 and the pressure reducing valve 222 may be located outside the input port 61 of the instrument 60, and the filter 221 may be closer to the input port 61 of the instrument 60 than the pressure reducing valve 222. In one embodiment, the pressure measurement unit 220 may be a contact-type pressure gauge, which can measure both positive and negative pressure and output the corresponding pressure measurement signal Sp. In another embodiment, the pressure measurement unit 220 may include a first contact-type pressure gauge and a second contact-type pressure gauge. The first contact-type pressure gauge is mainly used to measure positive pressure, and the second contact-type pressure gauge is mainly used to measure negative pressure. The first and second contact-type pressure gauges can output the pressure measurement signal Sp.

[0013] The fifth pneumatic valve 15 can be connected to an air inlet 31 of a vacuum pump 30 through a pipeline. The third pipeline group 23 connects the fifth pneumatic valve 15, the sixth pneumatic valve 16 and the output port 62 of the instrument 60. The fifth pneumatic valve 15 can control the connection or disconnection state between the air inlet 31 of the vacuum pump 30 and the third pipeline group 23.

[0014] The seventh pneumatic valve 17 can be connected to an exhaust port 32 of the vacuum pump 30 through a pipeline. The fourth pipeline group 24 connects the sixth pneumatic valve 16 and the seventh pneumatic valve 17. The end 240 of the fourth pipeline group 24 can be connected to an atmospheric pressure environment. The sixth pneumatic valve 16 can control the connection or disconnection state between the third pipeline group 23 and the fourth pipeline group 24. The seventh pneumatic valve 17 can control the connection or disconnection state between the exhaust port 32 of the vacuum pump 30 and the fourth pipeline group 24.

[0015] The plurality of solenoid valves 40 can be connected to a driving air source 42 through a pipeline group 41. The driving gas interface 100 of the first to seventh pneumatic valves 11~17 or the first to eighth pneumatic valves 11~18 can be connected to the plurality of solenoid valves 40 through pipelines respectively. That is to say, each pneumatic valve and each solenoid valve 40 can be a one-to-one connection structure. Each solenoid valve 40 is connected between the driving air source 42 and the driving gas interface 100 of each pneumatic valve. The opening or closing state of each solenoid valve 40 can respectively control the connection or disconnection state between the driving gas interface 100 of each pneumatic valve and the driving air source 42. The driving air source 42 can be, for example, an air compressor or a high-pressure gas container. The high-pressure gas container can be a gas cylinder.

[0016] The control unit 50 has the functions of information reception, storage, calculation and control. The control unit 50 can be, for example, a controller module or a computer host. The control unit 50 is electrically connected to the control contacts 400 of the plurality of solenoid valves 40. The control unit 50 can individually control the valve opening or closing state of the plurality of solenoid valves 40, thereby enabling the driving air source 42 to individually drive the valve opening or closing state of the first to seventh pneumatic valves 11 to 17 or the first to eighth pneumatic valves 11 to 18.

[0017] The control unit 50 can be electrically connected to the air pressure measuring unit 220 and the vacuum pump 30. The control unit 50 can receive the air pressure measuring signal Sp from the air pressure measuring unit 220. The control unit 50 can control the vacuum pump 30 to operate or not operate. The control unit 50 can output drive signals to the control contacts 400 of the plurality of solenoid valves 40 respectively, so as to individually control the valve opening or closing state of the plurality of solenoid valves 40.

[0018] The control unit 50 can be electrically connected to an alarm 70, which can be an alarm light or a buzzer. When the control unit 50 determines an abnormality, it can control the alarm 70 to issue an alarm to attract the attention of the staff. The control unit 50 can also be electrically connected to a touch screen display 71. The staff can set relevant parameters and valve actuation schedules for the control unit 50 through the touch screen display 71, so that the control unit 50 can operate accordingly. In addition, the control unit 50 can also control the touch screen display 71 to display the valve opening or closing status of each pneumatic valve and solenoid valve 40, as well as the air pressure value of the air pressure measurement signal Sp, for the staff to check.

[0019] It is understandable that, based on the physical principles of gas pressure and airflow such as gas flowing from high pressure to low pressure, gas pressure maintenance (pressure holding), positive pressure, negative pressure, etc., the control unit 50 can set relevant parameters and valve actuation schedules according to usage requirements to achieve functions such as cleaning, maintenance, calibration, and sample injection of pipeline groups, as shown below.

[0020] Please refer to Figure 1. When cleaning the pipeline, the control unit 50 can control the first and third pneumatic valves 11 and 13 to be in the valve open state (the remaining pneumatic valves are in the valve closed state, and the vacuum pump 30 does not operate). At this time, the airflow generated by the cleaning air source G_clean is injected into the second pipeline group 22 to form a positive pressure state in the pipeline, and the airflow can be used to purge the pipeline for cleaning. Then, the control unit 50 can further control the fifth and seventh pneumatic valves 15 and 17 to be in the valve open state (the remaining pneumatic valves are in the valve closed state) and control the vacuum pump 30 to operate. At this time, the vacuum pump 30 can extract the air in the second pipeline group 22 to form a negative pressure state, and the generated airflow can discharge impurities to clean the pipeline.

[0021] When the gas to be tested from the gas source G_test is to be fed into the instrument 60, the control unit 50, after cleaning the pipeline, mainly controls the second, third, fourth, and sixth pneumatic valves 12, 13, 14, and 16 to be in the open state (the remaining pneumatic valves are in the closed state, and the vacuum pump 30 does not operate) to inject the carrier gas and the gas to be tested into the pipeline. At this time, the gas to be tested can enter the instrument 60 for analysis, and then be discharged to the normal pressure environment through the sixth pneumatic valve 16 and the fourth pipeline group 24. That is to say, the sixth pneumatic valve 16 in the open state is used for normal pressure exhaust (Vent). Similarly, when the calibration gas from the calibration gas source G_standard is to be fed into the instrument 60, the second, eighth, third, and sixth pneumatic valves 12, 18, 13, and 16 are mainly controlled to be in the open state (the remaining pneumatic valves are in the closed state, and the vacuum pump 30 does not operate).

[0022] As described above, if the control unit 50 determines that the air pressure measurement signal Sp does not reach the positive pressure threshold or the negative pressure threshold within a preset time, the control unit 50 can control the alarm 70 to issue an alarm, indicating that the air pressure in the pipeline is not as expected, so that the staff can carry out maintenance after hearing the alarm. The preset time, positive pressure threshold, and negative pressure threshold are preset parameters of the control unit 50.

[0023] In summary, the automatic sample introduction system for gas impurity analysis of the present invention can be connected between the instrument 60 and various gas sources (i.e., clean gas source G_clean, carrier gas source G_carrier, calibration gas source G_standard, and test gas source G_test). The control unit 50 can control the opening or closing state of each pneumatic valve through each solenoid valve 40, realizing automatic control functions such as cleaning, maintenance, sample introduction and calibration of the pipeline group. The staff does not need to stay by the instrument 60 all the time, saving labor costs, greatly reducing human operation factors, avoiding human operation errors, and allowing the test gas to enter the instrument 60 for analysis through a clean pipeline environment, avoiding impurity interference, and effectively improving the accuracy and efficiency of gas analysis. [Simplified Explanation of the Diagram]

[0006] Figure 1: Schematic diagram of the piping configuration of an embodiment of the automatic gas impurity analysis system of the present invention. Figure 2: Schematic diagram of the piping configuration and circuit block diagram of an embodiment of the automatic gas impurity analysis system of the present invention.

Claims

1. An automated sample introduction system for gas impurity analysis, comprising: a first pneumatic valve connected to a clean gas source; a second pneumatic valve connected to a current-carrying gas source; a third pneumatic valve; a first pipeline assembly connecting the first, second, and third pneumatic valves; a fourth pneumatic valve connected to a gas source to be tested; a second pipeline assembly connecting the third and fourth pneumatic valves to an input port of an instrument; a fifth pneumatic valve connected to an inlet of a vacuum pump; a sixth pneumatic valve; a third pipeline assembly connecting the fifth and sixth pneumatic valves to an output port of the instrument; a seventh pneumatic valve connected to an exhaust port of the vacuum pump; and a fourth pipeline assembly connecting the sixth and seventh pneumatic valves. A plurality of solenoid valves are connected to a drive gas source, and the drive gas interfaces of the first to the seventh pneumatic valves are respectively connected to the plurality of solenoid valves; and a control unit is electrically connected to the control contacts of the plurality of solenoid valves. The control unit individually controls the valve opening or closing state of the plurality of solenoid valves, so that the drive gas source can individually drive the valves of the first to the seventh pneumatic valves to open or close.

2. The automated sample introduction system for gas impurity analysis as described in claim 1 further includes an eighth pneumatic valve connected to a calibration gas source, the first pipeline group connected to the eighth pneumatic valve, and the drive gas interfaces of the first to eighth pneumatic valves respectively connected to the plurality of solenoid valves; the control unit individually controls the valve opening or closing state of the plurality of solenoid valves, so that the drive gas source can individually drive the valve opening or closing state of the first to eighth pneumatic valves.

3. The automated sample introduction system for gas impurity analysis as described in claim 1, wherein, The second pipeline assembly is equipped with a pressure reducing valve.

4. The automated sample introduction system for gas impurity analysis as described in claim 1, wherein, The second pipeline assembly is equipped with a filter.

5. The automated sample introduction system for gas impurity analysis as described in claim 1, wherein, The second pipeline assembly is equipped with a pressure measurement unit, and the control unit is electrically connected to the pressure measurement unit.

6. The automated sample introduction system for gas impurity analysis as described in claim 1, wherein, The control unit is electrically connected to an alarm.

7. The automated sample introduction system for gas impurity analysis as described in claim 1, wherein, The control unit is electrically connected to a touch screen display.

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