Liquid sample injection control device for process gas chromatograph

Abstract

The invention relates to the technical field of gas chromatography, in particular to a liquid sample injection control device for a process gas chromatograph, which comprises a liquid phase vaporization mechanism used for vaporizing a liquid phase sample and mixing carrier gas, and the liquid phase vaporization mechanism comprises a carrier gas adjusting assembly, an atomizing assembly and a vaporization assembly which are sequentially connected end to end; the chromatographic column connector is arranged between the liquid phase vaporization mechanism and the chromatographic column and is used for conveying a vaporized sample to the chromatographic column; and the vaporization monitoring unit comprises a vibration sensor arranged on the atomization assembly and a second temperature sensor arranged on the chromatographic column connector, and is used for detecting the vaporization process of the liquid phase sample.

Description

Technical Field

[0001] The invention relates to the technical field of gas chromatography analysis, and in particular to a liquid injection control device for a process gas chromatograph. Background Art

[0002] In the field of gas chromatography technology, when injecting samples into a traditional gas chromatograph, liquid samples must be vaporized before entering the chromatographic column for separation. Traditional gas chromatograph injection devices mostly use manual or electric micro-injectors, which have the problem of uneven injection volume and inability to ensure sample repeatability. At the same time, traditional gas chromatograph injection devices also mostly use independent external vaporization devices, which have no control over the vaporization process, and have low vaporization efficiency and incomplete vaporization, which will cause serious tailing of the sample chromatographic peak and affect chromatographic separation.

[0003] Chinese Patent Publication No.: CN211122703U discloses a vaporization sampling device for online gas chromatography analysis of liquid samples, comprising: a four-way valve, a liquid sampling valve, and a vaporization device, wherein one end of the vaporization device is connected to the liquid sampling valve, and the other end of the vaporization device is connected to the four-way valve, and the vaporization device is also connected to a chromatograph, and the liquid sampling valve is connected to the four-way valve; it can be seen that the above-mentioned vaporization sampling device for online gas chromatography analysis of liquid samples has the following problems: the liquid sample injection amount is controlled by a traditional liquid sampling valve, the injection amount is uneven, and the liquid pipeline is complicated; at the same time, the liquid sample is directly dripped into the heating chamber, which is easy to adsorb on the tube wall or the valve body, and the vaporization process of the liquid sample is not controlled, the vaporization efficiency is low, and the vaporization is easy to be incomplete. Summary of the invention

[0004] To this end, the present invention provides a liquid injection control device for a process gas chromatograph to overcome the problems in the prior art of uneven liquid sample injection volume, complex liquid pipelines prone to sample residue, low liquid sample vaporization efficiency and incomplete vaporization.

[0005] To achieve the above object, the present invention provides a liquid injection control device for a process gas chromatograph, comprising: a chromatographic column connector inside the process gas chromatograph, and further comprising:

[0006] The injection mechanism comprises an injection needle, a telescopic probe assembly and a micro-quantitative ring, wherein the telescopic probe assembly is used to drive the injection needle to input the liquid sample into the micro-quantitative ring;

[0007] A liquid phase vaporization mechanism, which is connected to the sample injection mechanism and is used to convert the liquid phase sample and the carrier gas into a carrier gas mixed gas phase sample after mixing, comprising a carrier gas regulating component, an atomizing component and a vaporizing component connected end to end in sequence, wherein the carrier gas regulating component is used to adjust the pressure of the carrier gas to a target range so as to deliver the carrier gas to the atomizing component; the atomizing component is used to convert the liquid phase sample into a mist sample; the vaporizing component is used to vaporize the mist sample into a gas phase sample; the vaporizing component comprises a heating element, a glass vaporizing chamber and a heat insulating wall;

[0008] A vaporization monitoring mechanism, which is connected to the automatic sampling mechanism and the liquid phase vaporization mechanism respectively, and is used to collect sampling characteristic parameters, including the temperature of the gas in the vaporization component, the vibration amplitude of the atomization component, and the temperature of the chromatographic column connector;

[0009] The vaporization control mechanism is connected to the liquid phase vaporization mechanism and the vaporization monitoring mechanism respectively, and is used to adjust the carrier gas flow rate passing through the atomization component and the vaporization component according to the drop in the temperature of the chromatographic column connector, or to adjust the heating temperature of the vaporization component according to the vibration amplitude of the atomization component.

[0010] Furthermore, the telescopic probe rod assembly includes a cylinder, a piston arranged in the cylinder and connected to the injection needle, and a cylinder seal for preventing compressed air leakage and external contaminants from entering the cylinder. A pair of air holes are arranged on both sides of the piston on the cylinder to allow compressed air to enter and exit to drive the piston to move.

[0011] Furthermore, the vaporization monitoring mechanism comprises:

[0012] A first temperature sensor, connected to the injection needle, for detecting the temperature of the injection needle;

[0013] a second temperature sensor connected to the vaporization assembly and used to detect the temperature of the mixed gas in the vaporization assembly;

[0014] A third temperature sensor, connected to the chromatographic column connector, for detecting the temperature of the chromatographic column connector;

[0015] A vibration sensor is connected to the atomization assembly and is used to detect the vibration amplitude of the atomization assembly.

[0016] Furthermore, the carrier gas regulating component comprises:

[0017] A carrier gas pressure regulator is used to adjust the pressure of the carrier gas to a target pressure range and stabilize the pressure of the continuously input carrier gas;

[0018] An input carrier gas flow passage, which is arranged between the carrier gas storage device and the carrier gas pressure regulator, and is used to input the carrier gas into the carrier gas pressure regulator;

[0019] The atomization carrier gas flow channel is arranged between the carrier gas pressure regulator and the atomization component, and is used for inputting the carrier gas that converts the liquid phase sample into the atomization sample into the atomization component.

[0020] Furthermore, the vaporization control mechanism is respectively used with the first temperature sensor and the second temperature sensor to obtain the temperature of the injection needle detected by the first temperature sensor and the temperature of the mixed gas in the vaporization component detected by the second temperature sensor, and under the condition that the temperature of the injection needle and the temperature of the mixed gas in the vaporization component are less than or equal to a preset temperature, it is determined that the heating temperature of the heating element in the vaporization component is insufficient, and its heating temperature is increased.

[0021] Furthermore, the vaporization control mechanism is connected to the first temperature sensor, the second temperature sensor and the vibration sensor respectively, so as to obtain the vibration amplitude of the atomization assembly when the temperature of the injection needle and the temperature of the mixed gas in the vaporization assembly are greater than the preset temperature, wherein:

[0022] If the vibration amplitude of the atomization assembly is greater than a preset first vibration amplitude, the vaporization control mechanism determines that the vaporization state is unqualified;

[0023] If the vibration amplitude of the atomization assembly is less than or equal to the preset first vibration amplitude, the vaporization control mechanism determines that the vaporization state is qualified.

[0024] Furthermore, the vaporization control mechanism reduces the heating temperature of the vaporization component under the condition that the vibration amplitude of the atomization component is greater than or equal to a preset vibration amplitude.

[0025] Furthermore, the vaporization control mechanism is connected to the third temperature sensor to obtain the temperature of the chromatographic column connector.

[0026] If the temperature drop of the chromatographic column connector is greater than the preset drop, it is determined that the vaporization control mechanism is not sufficiently vaporized, and the flow rate of the carrier gas passing through the atomization component and the vaporization component is reduced.

[0027] Furthermore, the flow rate of the carrier gas passing through the atomization assembly and the vaporization assembly is negatively correlated with the drop amplitude of the chromatographic column connector.

[0028] Furthermore, the vaporization control mechanism also includes an air compressor for controlling the flow of compressed air into and out of the cylinder barrel and a hydraulic power pump for driving the pressure regulating action of the carrier gas regulating component.

[0029] Compared with the prior art, the beneficial effect of the present invention lies in that, by setting a carrier gas regulating component, an atomizing component and a vaporizing component, the injection control device of the present invention can determine, according to the temperature of the injection needle, whether the instability of the piston injection process is caused by the hot air flow of the heating element in the vaporization stage interfering with the temperature of the injection needle or by the vibration of the carrier gas and the injection structure caused by the unsmooth vaporization process of the vaporizing component, thereby reducing the influence of inaccurate identification of the cause of the instability of the injection needle on the accuracy of injection control; by adjusting the heating temperature of the heating element close to the atomizing component, adjusting the carrier gas flow rate and adjusting the overall heating temperature of the vaporizing component, respectively overcome the problem of gas flow interfering with the injection process caused by the heat difference between the heating section and the air heat at the injection position, the problem of inaccurate subsequent detection caused by insufficient vaporization entering the chromatographic column connector and the boiling of the liquid sample at the inlet of the vaporizing component, and the improvement of the accuracy of liquid injection control.

[0030] Furthermore, the liquid-phase vaporization mechanism of the present invention stabilizes the pressure of the continuously input carrier gas and controls the input flow rate of the carrier gas in real time by providing a carrier gas regulating component, thereby controlling the vaporization process of the liquid-phase sample and improving the safety of the device.

[0031] Furthermore, the liquid phase vaporization mechanism of the present invention improves the vaporization efficiency of the liquid phase sample and reduces the possibility of insufficient vaporization of the liquid phase sample by providing an atomization component.

[0032] Furthermore, the present invention sets a vibration sensor to detect the vibration amplitude of the atomization component. When the vibration amplitude exceeds a set threshold, the temperature of the electric heating wire is reduced to prevent the liquid sample from boiling at the inlet of the vaporization component, causing the vaporization component inlet pipe to vibrate and the measurement value to fluctuate.

[0033] Furthermore, the present invention sets a third temperature sensor to detect the temperature change of the chromatographic column connector. When the temperature of the chromatographic column connector drops, the carrier gas flow rate is reduced to prevent part of the liquid sample from directly entering the chromatographic column due to insufficient vaporization and causing damage to the instrument. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a structural schematic diagram of a liquid injection control device for a process gas chromatograph according to an embodiment of the present invention;

[0035] Figure 2 A schematic structural diagram of a carrier gas regulating assembly of a liquid injection control device for a process gas chromatograph according to an embodiment of the present invention;

[0036] In the figure: 121-cylinder barrel; 122-first compressed air inlet; 123-second compressed air inlet; 13-micro quantitative loop; 23-third temperature sensor; 31-glass vaporization chamber; 32-insulation wall mounting flange; 33-insulation wall; 4101-upper shell; 4102-lower shell; 4103-valve port; 4104-connecting rod; 4105-sealing rubber pad; 4106-upper pressure regulating spring; 4107-lower pressure regulating spring; 4108-piston assembly; 4109-membrane assembly; 4110-sealing assembly; 4111-pressure taking channel; 42-input carrier gasket; 43-atomization carrier gasket; 5-chromatographic column connector; 61-sample inlet; 62-sample outlet; 7-diversion channel. DETAILED DESCRIPTION

[0037] In order to make the objects and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0038] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0039] It should be noted that, in the description of the present invention, terms such as "up", "down", "left", "right", "inside" and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings. This is merely for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0040] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] See also Figure 1 As shown, an embodiment of the present invention provides a liquid injection control device for a process gas chromatograph, including a chromatographic column connector inside the process gas chromatograph, and also includes:

[0042] The injection mechanism comprises an injection needle, a telescopic probe assembly and a micro quantitative ring 13, wherein the telescopic probe assembly is used to drive the injection needle to input the liquid sample into the micro quantitative ring 13;

[0043] The liquid phase vaporization mechanism comprises a carrier gas regulating component, an atomizing component and a vaporizing component connected end to end in sequence; wherein a carrier gas input flow channel 42 connects a carrier gas pressure regulator 41 with a carrier gas storage device, so as to input carrier gas into the carrier gas pressure regulator 41; an atomizing carrier gas flow channel 43 connects the carrier gas pressure regulator 41 with the atomizing component, so as to allow carrier gas to enter the atomizing component 5 to atomize the liquid phase sample and enter the vaporizing component together with the liquid phase sample, and the vaporizing component is used to vaporize the atomized liquid phase sample;

[0044] The vaporization monitoring mechanism includes a first temperature sensor connected to the injection needle to detect the temperature of the injection needle; a second temperature sensor connected to the vaporization component to detect the temperature of the mixed gas in the vaporization component; a third temperature sensor 23 connected to the chromatographic column connector 5 to detect the temperature of the chromatographic column connector 5; and a vibration sensor connected to the atomization component to detect the vibration amplitude of the atomization component.

[0045] The vaporization control mechanism is respectively used with the first temperature sensor and the second temperature sensor to obtain the temperature of the injection needle detected by the first temperature sensor and the temperature of the mixed gas in the vaporization component detected by the second temperature sensor, and under the condition that the temperature of the injection needle and the temperature of the mixed gas in the vaporization component are less than or equal to the preset temperature, it is determined that the heating temperature of the heating element in the vaporization component is insufficient, and its heating temperature is increased.

[0046] The vaporization control mechanism is connected to the first temperature sensor, the second temperature sensor and the vibration sensor respectively, and is used to obtain the vibration amplitude of the atomization component when the temperature of the injection needle and the temperature of the mixed gas in the vaporization component are greater than the preset temperature, wherein:

[0047] If the vibration amplitude of the atomization assembly is greater than a preset first vibration amplitude, the vaporization control mechanism determines that the vaporization state is unqualified;

[0048] If the vibration amplitude of the atomization assembly is less than or equal to the preset first vibration amplitude, the vaporization control mechanism determines that the vaporization state is qualified.

[0049] The vaporization control mechanism reduces the heating temperature of the vaporization component under the condition that the vibration amplitude of the atomization component is greater than or equal to a preset vibration amplitude.

[0050] The vaporization control mechanism is connected to the third temperature sensor 23 to obtain the temperature of the chromatographic column connector 5.

[0051] If the temperature drop of the chromatographic column connector 5 is greater than the preset drop, it is determined that the vaporization control mechanism is not sufficiently vaporized, and the flow rate of the carrier gas passing through the atomization component and the vaporization component is reduced.

[0052] The flow rate of the carrier gas passing through the atomization component and the vaporization component is negatively correlated with the drop in temperature of the chromatographic column connector 5 .

[0053] The chromatographic column connector 10 is disposed between the liquid-phase vaporization mechanism and the chromatographic column and is used to transport the vaporized sample to the chromatographic column.

[0054] Specifically, see Figure 2 As shown, the carrier gas pressure regulating assembly includes:

[0055] The upper shell 4101 is sealed and connected with the diaphragm assembly 4109 and the lower shell 4102 in sequence. The upper end of the piston assembly 4108 is connected to the vaporization control mechanism, and the lower end is connected to the upper pressure-adjusting spring 4106, and is arranged in the chamber formed by the diaphragm assembly 4109 and the upper shell 4101; the upper end of the lower shell 4102 and the diaphragm assembly 4109 form a pressure-adjusting chamber, the inner side of the middle part is connected to the sealing assembly 4110 to form a connecting rod chamber, and the lower end is connected to the valve port 4103 to form a carrier gas chamber; the lower pressure-adjusting spring 4107 is arranged in the pressure-adjusting chamber, and the upper end of the piston assembly 4108 is connected to the diaphragm assembly 4109 to form a connecting rod chamber. The membrane assembly 4109 is connected, the connecting rod 4104 passes through the connecting rod chamber and is connected to the lower pressure regulating spring 4107, the upper end is connected to the membrane assembly 4109, and the lower end is connected to the sealing pad 4105. The sealing pad 4105 and the valve port 4103 divide the pressure regulating chamber into an inlet chamber and an outlet chamber, the inlet chamber is connected to the input carrier gas flow channel 42, and the outlet chamber is connected to the atomizing carrier gas flow channel 43; the pressure taking channel 4111 connects the pressure regulating chamber and the atomizing carrier gas flow channel 43 to obtain the carrier gas pressure in the atomizing carrier gas flow channel 43 and feed it back to the pressure regulating chamber;

[0056] It can be understood that the vaporization control mechanism controls the piston assembly 4108 to move up and down, adjusts the elastic force of the upper pressure regulating spring 4106 and the lower pressure regulating spring 4107 on the membrane assembly 4109; the carrier gas enters the inlet chamber through the input carrier gas flow channel 42, pushes the sealing gasket 4105 and the membrane assembly 4109 connected by the connecting rod 4104 to move downward, and a gap is generated between the sealing gasket 4105 and the valve port 4103, and the carrier gas flows into the outlet chamber and enters the atomized carrier gas flow channel 43; at this time, the incoming carrier gas causes the atomized carrier gas flow channel 4 3 rises, and enters the pressure regulating chamber through the pressure taking flow channel 4111. The air pressure in the pressure regulating chamber rises at the same time, pushing the membrane assembly 4109 and the sealing rubber pad 4105 connected by the connecting rod 4104 to move upward, the gap between the sealing rubber pad 4105 and the valve port 4103 is reduced, and the flow rate of the carrier gas into the outlet chamber is reduced. At this time, the air pressure in the atomized carrier gas flow channel 43 decreases, and the air pressure in the pressure regulating chamber decreases at the same time; the above process is repeated until the flow rate of the carrier gas is stable, that is, the pressure of the carrier gas in the atomized carrier gas flow channel 43 is stable;

[0057] Specifically, the atomization assembly is disposed at the entrance of the glass vaporization chamber 31 and is connected to the atomization carrier gas flow channel 43 .

[0058] Specifically, the vaporization assembly 6 includes:

[0059] The glass vaporization chamber 31 is connected to the atomization assembly and is used to vaporize the mist sample and fully mix it with the carrier gas; the insulation wall mounting flange 32 is arranged at the end of the glass vaporization chamber 31 and is used to mount the insulation wall.

[0060] Preferably, the glass vaporization chamber 31 is made of quartz glass, and the inner wall is coated with an inert silanized coating.

[0061] Preferably, the outlet temperature of the glass vaporization chamber 31 is set to be 20° higher than the inlet temperature thereof.

[0062] Preferably, the heating element is an electric heating wire.

[0063] The working principle and workflow of the present invention are:

[0064] The electric heating wire is controlled to preheat the glass vaporization chamber 31 in sections, so that the temperature at the inlet end of the glass vaporization chamber 31 reaches the vaporization temperature required by the liquid sample, and the temperature at the outlet end is 20° higher than the temperature at the inlet end; compressed air enters the cylinder barrel 121 through the second compressed air inlet 123 to push the piston forward, and pushes the telescopic probe assembly to drive the injection needle to input the liquid sample into the micro quantitative ring 13;

[0065] The vaporization control mechanism controls the carrier gas to be pressure-regulated and stabilized by the pressure regulator, and then enters the atomization assembly through the atomization carrier gas flow channel 43 to atomize the liquid sample in the micro-quantitative ring 13, and sprays the liquid sample into the glass vaporization chamber 31; at this time, the liquid sample is vaporized in the glass vaporization chamber 31 and mixed with the carrier gas, and the subsequent continuously input carrier gas enters the diversion flow channel through the diversion part of the diversion valve, and then is transported to the process gas chromatograph through the chromatographic column connector 5 for analysis.

[0066] Specifically, the vaporization control mechanism is respectively used with the first temperature sensor and the second temperature sensor to obtain the temperature of the injection needle detected by the first temperature sensor and the temperature of the mixed gas in the vaporization component detected by the second temperature sensor, and under the condition that the temperature of the injection needle and the temperature of the mixed gas in the vaporization component are less than or equal to the preset temperature, it is determined that the heating temperature of the heating element in the vaporization component is insufficient, and its heating temperature is increased.

[0067] Optionally, the preset temperature of the injection needle has an optional range of [50, 80], in degrees Celsius;

[0068] Preferably, the preferred embodiment of the preset temperature of the injection needle is 60°C;

[0069] In implementation, the heating temperature of the electric heating wire close to the atomization assembly is negatively correlated with the swing amplitude of the injection needle. When the swing amplitude of the injection needle exceeds the preset swing amplitude, the technicians in this field can set a gradient to increase the heating temperature of the electric heating wire close to the atomization assembly according to actual conditions.

[0070] In practice, the injection control device of the present invention is provided with a carrier gas regulating component, an atomizing component and a vaporizing component. When the stability of the piston injection process does not meet the requirements, it is determined according to the temperature of the injection needle whether the instability of the piston injection process is caused by the hot air flow of the heating element in the vaporization stage interfering with the temperature of the injection needle or by the vibration of the carrier gas and the injection structure caused by the unsmooth vaporization process of the vaporizing component, thereby reducing the influence of inaccurate identification of the cause of the instability of the injection needle on the accuracy of the injection control; by adjusting the heating temperature of the heating element close to the atomizing component, adjusting the carrier gas flow rate and adjusting the overall heating temperature of the vaporizing component, the problems of gas flow interfering with the injection process caused by the heat difference between the heating section and the air at the injection position, the problems of inaccurate subsequent detection caused by insufficient vaporization entering the chromatographic column connector and the boiling of the liquid sample at the inlet of the vaporizing component causing the injection structure to be unstable are overcome respectively, thereby achieving an overall improvement in the accuracy of liquid injection control.

[0071] Specifically, the vaporization control mechanism is connected to the first temperature sensor and the vibration sensor respectively, so as to obtain the vibration amplitude of the atomization assembly under the condition that the temperature of the injection needle is lower than the preset temperature and the swing amplitude of the injection needle is greater than or equal to the preset swing amplitude, wherein:

[0072] If the vibration amplitude of the atomization assembly is greater than a preset first vibration amplitude, the vaporization control mechanism determines that the vaporization state is unqualified;

[0073] If the vibration amplitude of the atomization assembly is less than or equal to the preset first vibration amplitude, the vaporization control mechanism determines that the vaporization state is qualified.

[0074] Specifically, the vaporization control mechanism reduces the heating temperature of the vaporization component under the condition that the vibration amplitude of the atomization component is greater than or equal to a preset second vibration amplitude.

[0075] Optionally, the optional range of the preset first vibration amplitude is [0.5, 2], and the unit is mm.

[0076] Preferably, the preset first vibration amplitude is 1.5 mm.

[0077] Optionally, the optional range of the preset second vibration amplitude is [2.2, 3], in units of mm.

[0078] Preferably, the preset second vibration amplitude is 2.6 mm.

[0079] In practice, the heating temperature of the vaporization component is reduced by 0.1°C every time the vibration amplitude of the atomization component exceeds the second vibration by 0.01mm. For example, when the vibration amplitude of the atomization component is 3.1mm, the current heating temperature of the vaporization component is 100°C, and the reduced heating temperature of the vaporization component is 100°C-(3.1mm-2.6mm) / 0.01×0.1°C=95°C.

[0080] During implementation, when it is identified based on the temperature of the injection needle that the vaporization process of the vaporization component is not smooth, resulting in vibration of the carrier gas and the injection structure, thereby causing instability in the piston injection process, and when the vibration amplitude of the atomization component exceeds the preset vibration amplitude, the technicians in this field can control the cylinder drive mechanism to drive the carrier gas pressure regulator to reduce the carrier gas flow rate allowed to pass according to actual conditions.

[0081] In practice, when the vibration amplitude of the atomization component exceeds the preset second vibration amplitude, it indicates that the liquid sample boils at the inlet of the vaporization component, resulting in an unstable injection structure. Technicians in this field can reduce the heating temperature of the electric heating wire according to actual conditions.

[0082] Specifically, if the vibration amplitude of the physical and chemical component is greater than the preset first vibration amplitude and less than the preset second vibration amplitude, the vaporization control mechanism preliminarily determines that the vaporization is insufficient, and obtains the decrease amplitude of the temperature of the chromatographic column connector.

[0083] If the temperature drop of the chromatographic column connector is greater than the preset drop, the vaporization control mechanism determines that the vaporization is insufficient for the second time, and reduces the flow rate of the carrier gas passing through the atomization component and the vaporization component.

[0084] Optionally, the preset temperature drop range is [3, 5], in degrees Celsius.

[0085] Preferably, the preset temperature drop is 3°C.

[0086] In practice, for every 0.21°C drop in the temperature of the chromatographic column connector beyond the preset drop, the carrier gas flow rate allowed to pass will be reduced by 0.01 sccm (standard milliliters per minute). For example, when the vibration amplitude of the atomization component is 2 mm, the current carrier gas flow rate is 15 sccm, and the reduced carrier gas flow rate is 15 sccm-(3.5°C-3°C) / 0.01×0.01 sccm=14.5 sccm.

[0087] In practice, when the temperature drop of the chromatographic column connector exceeds a set threshold, it indicates that the liquid sample is not fully vaporized and enters the chromatographic column connector, and is retained in the chromatographic column connector as a liquid, and is then vaporized by a subsequent high-temperature carrier gas to reduce the temperature of the chromatographic column connector. Those skilled in the art can control the cylinder drive mechanism to drive the carrier gas pressure regulator to reduce the carrier gas flow rate allowed to pass through, thereby increasing the vaporization time of the liquid sample in the vaporization component.

[0088] Specifically, the temperature drop amplitude of the chromatographic column connector is defined as: when the initial temperature of the chromatographic column connector minus the final temperature of the chromatographic column connector is positive within a unit time, this value is taken as the temperature drop amplitude of the chromatographic column connector.

[0089] Preferably, a possible embodiment of the unit time is 5s.

[0090] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A liquid injection control device for a process gas chromatograph, comprising a chromatographic column connector inside the process gas chromatograph, characterized in that: Also includes: The injection mechanism comprises an injection needle, a telescopic probe assembly and a micro-quantitative ring, wherein the telescopic probe assembly is used to drive the injection needle to input the liquid sample into the micro-quantitative ring; A liquid phase vaporization mechanism, which is connected to the sample injection mechanism and is used to convert the liquid phase sample and the carrier gas into a carrier gas mixed gas phase sample after mixing, comprising a carrier gas regulating component, an atomizing component and a vaporizing component connected end to end in sequence, wherein the carrier gas regulating component is used to adjust the pressure of the carrier gas to a target range so as to deliver the carrier gas to the atomizing component; The atomization component is used to convert the liquid sample into a mist sample; the vaporization component is used to vaporize the mist sample into a gaseous sample; the vaporization component includes a heating element, a glass vaporization chamber and an insulation wall; A vaporization monitoring mechanism, which is connected to the automatic sampling mechanism and the liquid phase vaporization mechanism respectively, and is used to collect sampling characteristic parameters, including the temperature of the gas in the vaporization component, the vibration amplitude of the atomization component, and the temperature of the chromatographic column connector; The vaporization control mechanism is connected to the liquid phase vaporization mechanism and the vaporization monitoring mechanism respectively, and is used to adjust the carrier gas flow rate passing through the atomization component and the vaporization component according to the drop in the temperature of the chromatographic column connector, or to adjust the heating temperature of the vaporization component according to the vibration amplitude of the atomization component.

2. The liquid injection control device for a process gas chromatograph according to claim 1, characterized in that: The telescopic probe rod assembly includes a cylinder, a piston arranged in the cylinder and connected to the injection needle, and a cylinder seal for preventing compressed air from leaking and external contaminants from entering the cylinder. A pair of air holes are arranged on both sides of the piston on the cylinder to allow compressed air to enter and exit to drive the piston to move.

3. The liquid injection control device for a process gas chromatograph according to claim 2, characterized in that: The vaporization monitoring mechanism comprises: A first temperature sensor, connected to the injection needle, for detecting the temperature of the injection needle; a second temperature sensor connected to the vaporization assembly and used to detect the temperature of the mixed gas in the vaporization assembly; A third temperature sensor, connected to the chromatographic column connector, for detecting the temperature of the chromatographic column connector; A vibration sensor is connected to the atomization assembly and is used to detect the vibration amplitude of the atomization assembly.

4. The liquid injection control device for a process gas chromatograph according to claim 3, characterized in that: The carrier gas regulating component comprises: A carrier gas pressure regulator is used to adjust the pressure of the carrier gas to a target pressure range and stabilize the pressure of the continuously input carrier gas; An input carrier gas flow passage, which is arranged between the carrier gas storage device and the carrier gas pressure regulator, and is used to input the carrier gas into the carrier gas pressure regulator; The atomization carrier gas flow channel is arranged between the carrier gas pressure regulator and the atomization component, and is used for inputting the carrier gas that converts the liquid phase sample into the atomization sample into the atomization component.

5. The liquid injection control device for a process gas chromatograph according to claim 4, characterized in that: The vaporization control mechanism is respectively used with the first temperature sensor and the second temperature sensor to obtain the temperature of the injection needle detected by the first temperature sensor and the temperature of the mixed gas in the vaporization component detected by the second temperature sensor, and under the condition that the temperature of the injection needle and the temperature of the mixed gas in the vaporization component are less than or equal to the preset temperature, it is determined that the heating temperature of the heating element in the vaporization component is insufficient, and its heating temperature is increased.

6. The liquid injection control device for a process gas chromatograph according to claim 5, characterized in that: The vaporization control mechanism is connected to the first temperature sensor, the second temperature sensor and the vibration sensor respectively, and is used to obtain the vibration amplitude of the atomization component when the temperature of the injection needle and the temperature of the mixed gas in the vaporization component are greater than the preset temperature, wherein: If the vibration amplitude of the atomization assembly is greater than a preset first vibration amplitude, the vaporization control mechanism determines that the vaporization state is unqualified; If the vibration amplitude of the atomization assembly is less than or equal to the preset first vibration amplitude, the vaporization control mechanism determines that the vaporization state is qualified.

7. The liquid injection control device for a process gas chromatograph according to claim 6, characterized in that: The vaporization control mechanism reduces the heating temperature of the vaporization component under the condition that the vibration amplitude of the atomization component is greater than or equal to a preset vibration amplitude.

8. The liquid injection control device for a process gas chromatograph according to claim 7, characterized in that: The vaporization control mechanism is connected to the third temperature sensor to obtain the temperature of the chromatographic column connector. If the temperature drop of the chromatographic column connector is greater than the preset drop, it is determined that the vaporization control mechanism is not sufficiently vaporized, and the flow rate of the carrier gas passing through the atomization component and the vaporization component is reduced.

9. The liquid injection control device for a process gas chromatograph according to claim 8, characterized in that: The flow rate of the carrier gas passing through the atomizing assembly and the vaporizing assembly is negatively correlated with the drop in temperature of the chromatographic column connector.

10. The liquid injection control device for a process gas chromatograph according to claim 9, characterized in that: The vaporization control mechanism also includes an air compressor for controlling the flow of compressed air into and out of the cylinder barrel and a hydraulic power pump for driving the pressure regulating action of the carrier gas regulating component.

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