Chromatographic detection system

Abstract

The utility model relates to the technical field of chromatographic analysis, and particularly provides a chromatographic detection system. The chromatographic detection system comprises a sampling valve, a multi-way valve, a first flow path, a second flow path, a third flow path, a first detection device and a second detection device, the sampling valve is provided with a plurality of sample inlets and a sample outlet, the plurality of sample inlets are respectively communicated with corresponding sampling points to be detected, the sample outlet is communicated with an inlet of the multi-way valve, and the first flow path is communicated with the first detection device. The multi-way valve comprises a first outlet, a second outlet and a third outlet, the first outlet of the multi-way valve is communicated with the first flow path, the second outlet of the multi-way valve is communicated with the second flow path, the third outlet of the multi-way valve is communicated with the third flow path, and the outlet of the first flow path and the outlet of the second flow path are respectively communicated with the first detection device; and an outlet of the third flow path is communicated with the first detection device. The chromatographic detection system provided by the utility model is used for sampling, analyzing and detecting a plurality of sampling points and samples with different phase states in the same process place.

Description

Technical Field

[0001] The utility model relates to the technical field of chromatographic analysis, in particular to a chromatographic detection system. Background Art

[0002] In industrial production process control, sampling ports are installed on process pipelines and equipment to analyze the phase composition within the detection system in order to timely monitor the process status of production equipment. However, the entire process of process detection is subject to the problem of multiple analysis points and different sample phases.

[0003] Currently, sampling is typically done manually, such as using high-pressure cylinders to collect gas and volatile liquid samples, and ordinary glass or plastic containers to collect liquid samples. This method is time-consuming and labor-intensive, with low detection efficiency and a time lag in applying data to guide process production. Alternatively, analytical huts can be constructed at different locations, employing different sampling, processing systems, and testing equipment based on the state of the materials. This requires extensive utilities and materials, resulting in high costs. Utility Model Content

[0004] In view of the above problems, the present invention is proposed. The present invention provides a chromatography detection system that can perform sampling, analysis and detection on multiple sampling points and different types of samples in the same location.

[0005] According to one aspect of the present utility model, a chromatographic detection system is provided, which is applied to a place with multiple sampling points to be detected, comprising: a sampling valve, a multi-way valve, a first flow path, a second flow path, a third flow path, a first detection device and a second detection device, wherein the sampling valve has multiple sample inlets and a sample outlet, the multiple sample inlets are respectively connected to corresponding sampling points to be detected, the sample outlet is connected to the inlet of the multi-way valve, the multi-way valve includes a first outlet, a second outlet and a third outlet, the first outlet of the multi-way valve is connected to the first flow path, the second outlet of the multi-way valve is connected to the second flow path, and the third outlet of the multi-way valve is connected to the third flow path;

[0006] The outlet of the first flow path and the outlet of the second flow path are respectively communicated with the first detection device, and the outlet of the third flow path is communicated with the second detection device.

[0007] Compared with the prior art, the chromatographic detection system provided by the present utility model is applied to a place with multiple sampling points to be detected. The chromatographic detection system includes: a sampling valve, a multi-way valve, a first flow path, a second flow path, a third flow path, a first detection device, and a second detection device. Since the sampling valve has multiple sample inlets and one sample outlet, the multiple sample inlets are respectively connected to the corresponding sampling points to be detected, and the sample outlet is connected to the inlet of the multi-way valve. Therefore, the target sampling point to be detected can be connected to the corresponding sample inlet of the sampling valve, and the sampling valve is used to sample the target sampling point to be detected, and the collected target sample to be detected is transported to the multi-way valve through the sample outlet of the sampling valve.

[0008] At this time, since the multi-way valve includes a first outlet, a second outlet, and a third outlet, the first outlet of the multi-way valve is connected to the first flow path, the second outlet of the multi-way valve is connected to the second flow path, the third outlet of the multi-way valve is connected to the third flow path, the outlets of the first flow path and the second flow path are respectively connected to the first detection device, and the outlet of the third flow path is connected to the second detection device. If the target sample to be detected is a gas sample, the multi-way valve can be connected to the first flow path, and the first flow path is used to transport the target sample to be detected to the first detection device for detection; if the target sample to be detected is a volatile liquid sample, the multi-way valve is connected to the second flow path, and the second flow path is used to transport the target sample to be detected to the first detection device for detection; if the target sample to be detected is a liquid sample, the multi-way valve is connected to the third flow path, and the third flow path is used to transport the target sample to be detected to the second detection device for detection. Therefore, sampling analysis and detection of multiple sampling points and different phase state samples are achieved in the same process site. Using the same integrated system, the requirements for gas, volatile liquid, and liquid sampling analysis can be satisfied simultaneously, saving space layout and investment. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] By describing the embodiments of the present utility model in more detail in conjunction with the drawings, the above and other objects, features, and advantages of the present utility model will become more obvious. The drawings are used to provide a further understanding of the embodiments of the present utility model, and constitute a part of the specification. Together with the embodiments of the present utility model, they are used to explain the present utility model and do not constitute a limitation to the present utility model. In the drawings, the same reference numerals generally represent the same components or steps.

[0010] Figure 1 is the process flow chart of the chromatographic detection system provided by the embodiment of the present utility model;

[0011] Figure 2 is the structural schematic diagram of the sampling valve provided by the embodiment of the present utility model;

[0012] Figure 3 is the schematic diagram of the multi-way valve of the embodiment of the present utility model;

[0013] Figure 4 This is a schematic structural diagram of the flash tank according to an embodiment of the present utility model.

[0014] Reference numerals:

[0015] 100 - sampling valve, 110 - sample inlet, 120 - sample outlet, 200 - multi - way valve, 210 - first outlet of the multi - way valve, 220 - second outlet of the multi - way valve, 230 - third outlet of the multi - way valve, 300 - first flow path, 310 - first flow - rate reducing valve, 400 - second flow path, 410 - second flow - rate reducing valve, 420 - flash tank, 430 - first three - way valve, 430a - first inlet of the first three - way valve, 430b - second inlet of the first three - way valve, 440 - second three - way valve, 440a - first outlet of the second three - way valve, 440b - second outlet of the second three - way valve, 450 - gas sampling metering valve, 451 - first carrier gas inlet, 460 - adiabatic double - pass, 500 - third flow path, 510 - flow regulating valve, 520 - micro - liquid sampling valve, 521 - liquid vent outlet, 522 - second carrier gas inlet, 530 - third check valve, 600 - first detection device, 700 - second detection device; 800 - first gas vent flow path, 810 - flowmeter, 820 - first back - pressure valve, 830 - first check valve, 900 - second gas vent flow path, 910 - second back - pressure valve, 920 - second check valve, 1000 - inert gas purge unit, 1100 - filter, 1200 - equipment root valve. Detailed implementation manners

[0016] In order to make the objectives, technical solutions and advantages of the present utility model more obvious, the exemplary embodiments according to the present utility model will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments of the present utility model. It should be understood that the present utility model is not limited by the exemplary embodiments described herein.

[0017] In industrial production process control, in order to timely grasp the process state of the production device, sampling ports are set on the process pipelines and devices for analyzing and detecting the phase composition in the system. There are problems of many analysis points and different sample states in the whole process detection. For example, in the production process of synthesizing liquefied natural gas from coke oven gas, it is necessary to timely understand the composition of methane, carbon monoxide, carbon dioxide, hydrogen, and nitrogen in the raw material gas and production process gas, and also to test the composition change of liquefied natural gas and liquid refrigerant. In the production process of methanol - to - olefins, it is necessary to detect the material composition of different phases such as raw material methanol and product olefins.

[0018] In the above process, the material composition analysis in the production process mostly uses gas chromatography. The gas chromatography separation and detection technologies for various materials have been relatively mature. At present, the main links affecting the efficiency and accuracy of material analysis and detection are the sampling and pretreatment processes. Generally, manual sampling is used. For example, a high-pressure gas cylinder is used to collect gas samples and volatile liquid samples, and ordinary glass or plastic containers are used to hold liquid samples. This method is time-consuming and laborious, and the detection efficiency is relatively low. For guiding the process production with application data, there is a time lag. Or analysis cabins are built at different positions, and different sampling, treatment systems and detection equipment are adopted according to the states of different materials. The required utilities and materials are relatively many, and the cost is relatively high.

[0019] In view of the above problems, an embodiment of the present utility model provides a chromatographic detection system, which can perform sampling analysis and detection on multiple sampling points and different phase samples in the same process site. It solves the problems of time-consuming and laborious manual sampling in the prior art, as well as low efficiency, large occupied space and high cost when separately establishing chromatographic analysis systems at different sampling points.

[0020] Figure 1 The process flow diagram of the chromatographic detection system provided by the embodiment of the present utility model is shown. It is applied to a site with multiple sampling points to be detected, and can realize sample sampling and analysis for multiple sampling points in the same process site. Figure 2 The structural schematic diagram of the sampling valve provided by the embodiment of the present utility model is shown. As Figure 1 and Figure 2 shown, the chromatographic detection system of the embodiment of the present utility model includes: a sampling valve 100, a multi-way valve 200, a first flow path 300, a second flow path 400, a third flow path 500, a first detection device 600 and a second detection device 700. The sampling valve 100 has multiple sample inlets 110 and a sample outlet 120. The multiple sample inlets 110 are respectively connected to the corresponding sampling points to be detected, and the sample outlet 120 is connected to the inlet of the multi-way valve 200. The multi-way valve 200 includes a first outlet 210, a second outlet 220 and a third outlet 230. The first outlet 210 of the multi-way valve 200 is connected to the first flow path 300, the second outlet 220 of the multi-way valve 200 is connected to the second flow path 400, and the third outlet 230 of the multi-way valve 200 is connected to the third flow path 500. Among them, the outlets of the first flow path 300 and the second flow path 400 are respectively connected to the first detection device 600, and the outlet of the third flow path 500 is connected to the second detection device 700.

[0021] It can be understood that the number of the multiple sample inlets 110 of the above sampling valve 100 can be 4 to 16, which can be specifically selected according to needs and is not limited herein. Thus, during the analysis process, the multiple sample inlets 110 can be respectively connected to multiple target sampling points to be detected, and can be manually or programmatically controlled to select the sample of a certain target sampling point to be detected to enter the injection system, and then enter the first detection device 600 or the second detection device 700 for analysis.

[0022] The above first flow path 300 is a gas sample injection flow path, the second flow path 400 is a volatile liquid sample injection flow path, and the third flow path 500 can be a liquid sample injection flow path.

[0023] It should be noted that the gas sample described in the present utility model refers to a sample in which all components are in a gas state under the process or experimental temperature and pressure. For example, it can be listed as: nitrogen, carbon monoxide, carbon dioxide, methane mixture, but not limited thereto. The volatile liquid sample described in the present utility model refers to a sample in which the components in the sample are liquid mixtures under the process or experimental temperature and pressure, and are gas-liquid mixtures under normal temperature and pressure, and the boiling range distribution is relatively wide. For example, it can be listed as: liquefied petroleum gas, hydrocarbons with 8 or less carbon atoms and their mixtures, but not limited thereto. The liquid sample described in the present utility model refers to a sample in which the boiling point of the components is relatively high and is in a liquid state under normal temperature and pressure. For example, it can be listed as: alcohols such as methanol and ethanol, gasoline, diesel, but not limited thereto. In addition, although the three types of samples are defined as above in this application, the classification of related samples can be adjusted according to needs. For example, a mixture of methane and alcohols can be classified into different types according to the content of methane. Specifically, if the methane content is high and the overall sample state is in a gas state, the sample type can be classified as a gas medium; if the methane and alcohol contents are equivalent, the sample type can be classified as a volatile medium; if the alcohol content is high and the overall sample state is in a liquid state, the sample type can be classified as a liquid medium.

[0024] The above first detection device 600 can be a gas chromatograph, the second detection device 700 can include a vaporization device and a gas chromatograph, and the liquid coming out of the third flow path 500 can enter the vaporization device of the second detection device 700 to be converted into a gas, and the gas then enters the gas chromatograph for detection.

[0025] Figure 3 The schematic diagram of the multi-way valve of the embodiment of the present utility model is shown. As Figure 3 shown, the above multi-way valve 200 can be a one-in-three-out valve, so that the first flow path 300, the second flow path 400, and the third flow path 500 can be connected to the target sample to be detected through the multi-way valve 200.

[0026] In specific implementation, when it is necessary to sample and analyze a target sampling point to be detected, first, the target sampling point to be detected can be connected to the corresponding sample inlet 110 of the sampling valve 100, and the sampling valve 100 is used to sample the target sampling point to be detected. The collected target sample to be detected is transported to the multi-way valve 200 through the sample outlet 120 of the sampling valve 100. At this time, if the target sample to be detected is a gas sample, the multi-way valve 200 can be connected to the first flow path 300 to transport the target sample to be detected to the first detection device 600 for detection by using the first flow path 300; if the target sample to be detected is a volatile liquid sample, the multi-way valve 200 is connected to the second flow path 400 to transport the target sample to be detected to the first detection device 600 for detection by using the second flow path 400; if the target sample to be detected is a liquid sample, the multi-way valve 200 is connected to the third flow path 500 to transport the target sample to be detected to the second detection device 700 for detection. Therefore, sampling analysis and detection for multiple sampling points and different-phase samples are achieved within the same process site. By using the same integrated system, the requirements for gas, volatile liquid, and liquid sampling analysis can be satisfied simultaneously, saving space layout and investment.

[0027] In an implementable manner, the first flow path 300 of the embodiment of the present utility model includes a first flow pressure reducing valve 310, and the first outlet 210 of the multi-way valve 200 is connected to the inlet of the first flow pressure reducing valve 310.

[0028] In specific implementation, if the target sample to be detected is a gas sample, the multi-way valve 200 is connected to the first flow pressure reducing valve 310, and the first flow pressure reducing valve 310 is used to transport the target sample to be detected to the first detection device 600 for detection.

[0029] Exemplarily, the second flow path 400 of the embodiment of the present utility model includes a second flow pressure reducing valve 410, a flash tank 420, a first three-way valve 430, a second three-way valve 440, and a gas injection metering valve 450. The second outlet 220 of the multi-way valve 200 is connected to the inlet of the second flow pressure reducing valve 410, the outlet of the second flow pressure reducing valve 410 is connected to the inlet of the flash tank 420, the outlet of the flash tank 420 is connected to the first inlet 430a of the first three-way valve 430, the outlet of the first three-way valve 430 is connected to the second three-way valve 440, the first outlet 440a of the second three-way valve 440 is connected to the inlet of the gas injection metering valve 450, and the first outlet of the gas injection metering valve 450 is connected to the first detection device 600.

[0030] It should be understood that the above gas sampling quantitative valve 450 can be a six-way sampling valve. A quantitative loop is provided on the six-way sampling valve for quantitatively introducing gas into the chromatograph. The volume of the quantitative loop is the volume of the sample entering the chromatograph injection port. The volume of the quantitative loop is preferably 50 μl to 5000 μl, and more preferably 50 μl to 2000 μl.

[0031] During specific implementation, after sampling the target sample to be detected, if the target sample to be detected is a volatile liquid sample, first, connect the multi-way valve 200 and the second flow pressure reducing valve 410, and use the second flow pressure reducing valve 410 to transport the target volatile liquid sample to the flash evaporation tank 420; then, use the flash evaporation tank 420 to flash the target sample to be detected, so that the target sample to be detected is converted into gas; next, transport the gas to the first three-way valve 430, the second three-way valve 440 and the gas sampling quantitative valve 450 in sequence for injection quantification; finally, transport the quantified gas to the first detection device 600 for detection.

[0032] In an optional manner, the outlet of the first flow pressure reducing valve 310 in the embodiment of the present invention is connected to the second inlet 430b of the first three-way valve 430.

[0033] During specific implementation, the first flow pressure reducing valve 310 can be used to transport the target sample to be detected to the first three-way valve 430, the second three-way valve 440 and the gas sampling quantitative valve 450 in sequence for injection quantification.

[0034] In one example, Figure 4 shows a schematic structural diagram of the flash evaporation tank in the embodiment of the present invention. As Figure 4 shown, both ends of the flash evaporation tank 420 in the embodiment of the present invention are conical, and the conical angle α of the cone is less than 60°, which can reduce the problems of long replacement time and inaccurate analysis caused by sample residue during the sample replacement process.

[0035] Exemplarily, the volume of the flash evaporation tank 420 in the embodiment of the present invention is 10 ml to 50 ml, and more preferably 20 ml, so as to ensure sufficient gasification space and heat capacity, avoid excessive increase in replacement time, and improve the analysis efficiency.

[0036] In an optional manner, an adiabatic double-pass 460 is further provided between the second flow pressure reducing valve 410 and the flash evaporation tank 420 in the embodiment of the present invention. Among them, the adiabatic double-pass 460 is made of adiabatic material (such as PEEK or PTFE), so as to avoid uneven gasification of the sample due to heat conduction before entering the flash evaporation tank 420.

[0037] In specific implementation, the above-mentioned second flow reducing valve 410 can be used to transport the target volatile liquid sample to the adiabatic double-pass 460 for adiabatic condensation, and then transport the adiabatically condensed target volatile liquid sample to the flash tank 420 for flash evaporation.

[0038] Exemplarily, the chromatographic detection system of the embodiment of the present invention further includes a first gas venting flow path 800, and the second outlet 440b of the second three-way valve 440 is communicated with the inlet of the first gas venting flow path 800.

[0039] In specific implementation, if the target sample to be detected is a gas sample or a volatile liquid sample, before detecting the target sample to be detected, the second three-way valve 440 and the first gas venting flow path 800 are connected to vent and displace the gas sample or the volatile liquid sample. Thereby, the impurity gas and air in the first flow path or the second flow path can be emptied, making the analyzed data and the gas components or the discovered liquid components more accurate.

[0040] In one example, the first gas venting flow path 800 of the embodiment of the present invention includes a flow meter 810, a first back pressure valve 820 and a first one-way valve 830. The second outlet 440b of the second three-way valve 440 is communicated with the inlet of the flow meter 810. The outlet of the flow meter 810 is communicated with the inlet of the first back pressure valve 820. The inlet of the first back pressure valve 820 is communicated with the inlet of the first one-way valve 830. The outlet of the first one-way valve 830 is communicated with the external space.

[0041] In specific implementation, if the target sample to be detected is a gas sample or a volatile liquid sample, before detecting the target sample to be detected, the second three-way valve 440, the flow meter 810, the first back pressure valve 820 and the first one-way valve 830 are connected in sequence to vent the gas sample or the volatile liquid sample. Thereby, the impurity gas and air in the first flow path or the second flow path can be emptied, making the analyzed data and the gas components or the discovered liquid components more accurate. It should be understood that the first one-way valve 830 can prevent abnormal pressure in the venting pipeline and cause backflow.

[0042] It can be understood that the pressure value of the above-mentioned first back pressure valve 820 is 100 kPa to 300 kPa. Setting the pressure within this range can avoid the influence of the size of the first back pressure valve 820 on the pressure in the flash tank 420 to a certain extent.

[0043] Exemplarily, the chromatographic detection system of the embodiment of the present invention further includes a second gas venting flow path 900. The gas sampling quantitative valve 450 has a first carrier gas inlet 451, and the second outlet of the gas sampling quantitative valve 450 is communicated with the second gas venting flow path 900.

[0044] In specific implementation, if the pressure in the gas sampling metering valve 450 is greater than or less than the pressure at the first carrier gas inlet 451, the gas sampling metering valve 450 is connected to the second gas vent flow path 900. Therefore, the pressure in the gas sampling metering valve 450 can be set to the same value as the pressure in the first carrier gas inlet 451, so that the pressure value in the sampling loop is constant, and then the amount of substance is kept constant, ensuring the repeatability of chromatographic sampling and minimizing the system pressure fluctuation during the switching process of the second three-way valve 440.

[0045] In an optional manner, the second gas vent flow path 900 of the embodiment of the present utility model includes a second back pressure valve 910 and a second check valve 920. The second outlet of the gas sampling metering valve 450 is connected to the inlet of the second back pressure valve 910, the outlet of the second back pressure valve 910 is connected to the inlet of the second check valve 920, and the outlet of the second check valve 920 is connected to the external space.

[0046] In specific implementation, if the pressure in the gas sampling metering valve 450 is greater than or less than the pressure at the first carrier gas inlet 451, the gas sampling metering valve 450, the second back pressure valve 910 and the second check valve 920 are connected in sequence. Thus, the excess pressure in the gas sampling metering valve 450 can be released, and the pressure in the gas sampling metering valve 450 is kept the same as that in the second three-way valve 440 to reduce the system pressure fluctuation during the switching process of the second three-way valve 440.

[0047] In an optional manner, the third flow path 500 of the embodiment of the present utility model includes a flow regulating valve 510 and a micro liquid sampling valve 520. The third outlet 230 of the multi-way valve 200 is connected to the inlet of the flow regulating valve 510, the outlet of the flow regulating valve 510 is connected to the inlet of the micro liquid sampling valve 520, and the first outlet of the micro liquid sampling valve 520 is connected to the second detection device 700. Among them, the micro liquid sampling valve 520 is used for the sampling analysis of liquid samples.

[0048] In specific implementation, if the target sample to be detected is a liquid sample, the multi-way valve 200, the flow regulating valve 510 and the micro liquid sampling valve 520 are connected in sequence for sampling and quantification, and the quantified liquid sample is transported to the second detection device 700 for detection.

[0049] Exemplarily, the micro liquid sampling valve 520 of the embodiment of the present utility model further has a liquid vent outlet 521 and a second carrier gas inlet 522, and the liquid vent outlet 521 is also connected to the external through a third check valve 530. The third check valve 530 can prevent the abnormal pressure in the vent pipeline from causing backflow.

[0050] In specific implementation, when the pressure in the micro liquid sampling valve 520 is greater than the second carrier gas inlet 522, the pressure in the micro liquid sampling valve 520 is released by using the liquid vent outlet 521.

[0051] Exemplarily, the pressures of the above-mentioned first carrier gas inlet 451 and the second carrier gas inlet 522 can be set to the same pressure, so as to further reduce the fluctuations during the switching process of the second three-way valve 440.

[0052] In one example, the chromatographic detection system of the embodiment of the present invention further includes an inert gas purging unit 1000, and the inert gas purging unit 1000 is connected to the sampling valve 100. Before each sampling, the sampling valve 100 can be purged and replaced by using the inert gas purging unit 1000 to reduce the sample cross-contamination between two analyses of the sample. Among them, the inert gas can be nitrogen, helium, argon or other inert gases, which is not limited herein.

[0053] Exemplarily, the chromatographic detection system of the embodiment of the present invention further includes a filter 1100. The inlet of the filter 1100 is connected to the sampling point to be detected, and the outlet of the filter 1100 is connected to the inlet of the sampling valve 100. The filter 1100 includes a primary filtering unit and a secondary filtering unit. The aperture of the filtering holes of the primary filtering unit is 8 μm to 10 μm, and the aperture of the filtering holes of the secondary filtering unit is 1 μm to 2 μm. The setting of the filter 1100 can effectively prevent the subsequent sample pipeline from being blocked and prevent the wear of the valve parts.

[0054] In one example, the flash tank 420, the first three-way valve 430, the second three-way valve 440, and the gas sampling metering valve 450 of the embodiment of the present invention are placed in the same heating zone. The heating zone provides vaporization heat for the flash vaporizer and at the same time ensures that the vaporized sample does not condense in the injection system. The temperature of the heating zone can be set according to the actual boiling point distribution of the sample, preferably 80 °C to 200 °C, more preferably 80 °C to 120 °C.

[0055] Exemplarily, all valves in the chromatographic detection system of the embodiment of the present invention can be manually switched or controlled by a program.

[0056] For example, the chromatographic detection system of the embodiment of the present invention further includes a plurality of equipment root valves 1200. The plurality of equipment root valves 1200 are respectively arranged at the sample outlets of each sampling point to be detected, and each equipment root valve 1200 is respectively connected to the filter 1100.

[0057] Exemplarily, the pipelines, valves, flash tanks, etc. (except the vent pipeline) between the sampling ports of all process equipment or samplers and the chromatographic injection port of the embodiment of the present invention are made of passivated stainless steel materials, which can avoid the adsorption of samples containing active components such as sulfur, oxygen, ammonia gas, etc. during the injection process and reduce the analysis accuracy.

[0058] The embodiment of the present utility model provides a chromatographic detection method, which can be applied to the chromatographic detection system of the embodiment of the present utility model. The chromatographic detection method of the embodiment of the present utility model includes:

[0059] Step 101: Connect the target sampling point to be detected with the corresponding sample inlet, sample the target sampling point to be detected by using a sampling valve, and transport the collected target sample to be detected to a multi-way valve.

[0060] Step 102: If the target sample to be detected is a gas sample, connect the multi-way valve to the first flow path, and transport the target sample to be detected to the first detection device for detection by using the first flow path; if the target sample to be detected is a volatile liquid sample, connect the multi-way valve to the second flow path, and transport the target sample to be detected to the first detection device for detection by using the second flow path; if the target sample to be detected is a liquid sample, connect the multi-way valve to the third flow path, and transport the target sample to be detected to the second detection device for detection.

[0061] In an optional manner, the above-mentioned if the target sample to be detected is a gas sample, connecting the multi-way valve to the first flow path and transporting the target sample to be detected to the first detection device for detection specifically includes: if the target sample to be detected is a gas sample, connecting the multi-way valve to a first flow rate reducing valve, and transporting the target sample to be detected to the first detection device for detection by using the first flow rate reducing valve.

[0062] In an implementable manner, the above-mentioned if the target sample to be detected is a volatile liquid sample, connecting the multi-way valve to the second flow path and transporting the target sample to be detected to the first detection device for detection specifically includes: First, if the target sample to be detected is a volatile liquid sample, connect the multi-way valve to a second flow rate reducing valve, and transport the target volatile liquid sample to a flash evaporation tank by using the second flow rate reducing valve. Then, flash the target sample to be detected by using the flash evaporation tank so that the target sample to be detected is converted into a gas. Next, transport the gas to a first three-way valve, a second three-way valve and a gas injection quantitative valve in sequence for injection quantification. Finally, transport the quantified gas to the first detection device for detection.

[0063] Exemplarily, the above-mentioned transporting the target sample to be detected to the first detection device for detection by using the first flow rate reducing valve specifically includes: First, transport the target sample to be detected to a first three-way valve, a second three-way valve and a gas injection quantitative valve in sequence for injection quantification by using the first flow rate reducing valve. Then, transport the quantified gas to the first detection device for detection.

[0064] In one example, a second flow pressure reducing valve is used to deliver a target volatile liquid sample to a flash tank, which specifically includes: First, the second flow pressure reducing valve is used to deliver the target volatile liquid sample to an adiabatic double-pass for adiabatic condensation. Then, the adiabatically condensed target volatile liquid sample is delivered to the flash tank for flash evaporation.

[0065] Exemplarily, the chromatographic detection method of the embodiment of the present utility model further includes: If the target sample to be detected is a gas sample or a volatile liquid sample, before detecting the target sample to be detected, the second three-way valve and the first gas vent flow path are connected to vent the gas sample or the volatile liquid sample.

[0066] In one example, if the target sample to be detected is a gas sample or a volatile liquid sample, before detecting the target sample to be detected, the second three-way valve and the first gas vent flow path are connected to vent the gas sample or the volatile liquid sample, which specifically includes: If the target sample to be detected is a gas sample or a volatile liquid sample, before detecting the target sample to be detected, the second three-way valve, a flow meter, a first back pressure valve, and a first one-way valve are sequentially connected to vent the gas sample or the volatile liquid sample.

[0067] In an optional manner, the chromatographic detection method of the embodiment of the present utility model further includes: If the pressure in the gas sampling metering valve is greater than or less than a first preset pressure, the gas sampling metering valve is connected to the second gas vent flow path.

[0068] Exemplarily, if the pressure in the gas sampling metering valve is greater than or less than a first preset pressure, connecting the gas sampling metering valve to the second gas vent flow path specifically includes: If the pressure in the gas sampling metering valve is greater than or less than a first preset pressure, the gas sampling metering valve, a second back pressure valve, and a second one-way valve are sequentially connected.

[0069] In an optional manner, if the target sample to be detected of the present utility model is a liquid sample, the multi-way valve is connected to the third flow path, and the third flow path is used to deliver the target sample to be detected to the second detection device for detection, which specifically includes: If the target sample to be detected is a liquid sample, the multi-way valve, a flow regulating valve, and a micro liquid injection valve are sequentially connected for sample injection quantification, and then the quantified liquid sample is delivered to the second detection device for detection.

[0070] Exemplarily, the chromatographic detection method of the embodiment of the present utility model further includes: When the pressure in the micro liquid injection valve is greater than or less than a second preset pressure, the micro liquid injection valve is vented through the liquid vent outlet.

[0071] In an achievable manner, the chromatographic detection method of the embodiment of the present utility model further includes: Before each sampling, an inert gas purging unit is used to purge the sampling valve.

[0072] Exemplarily, the chromatographic detection method according to an embodiment of the present invention further includes: before each sampling, filtering the sample to be detected by using a filter, and conveying the filtered sample to be detected to a sampling valve.

[0073] For the chromatographic detection system according to an embodiment of the present invention, the setting of the multi-way valve can be connected to the sampling ports or samplers of multiple devices. Combined with program control, automatic control and continuous analysis can be achieved, and the detection efficiency can be improved. Moreover, by using the same integrated system, the detection requirements of gas, volatile liquid, and liquid sampling analysis can be simultaneously satisfied, saving space layout and investment. The chromatographic detection system according to an embodiment of the present invention can be connected to a process pipeline to achieve on-line chromatographic analysis, or can be connected to a high-pressure gas (liquid) sampler for off-line chromatographic analysis.

[0074] Embodiment 1

[0075] The present invention provides an embodiment of the process for injecting volatile samples (the first flow path), such as the detection of the composition of the raw materials for synthetic natural gas from coke oven gas: The main components of the raw material gas for synthetic natural gas from coke oven gas are hydrogen, carbon monoxide, carbon dioxide, nitrogen, methane, ethane, and a small amount of propane and butane, which are all in a gaseous state at room temperature and normal pressure. The specific operation steps are as follows:

[0076] Set the temperature of the heating zone to 80 °C and wait for the temperature of the heating zone to be stable. First, adjust the first three-way valve so that its inlet end is connected to the first flow pressure reducing valve and its outlet end is connected to the second three-way valve. Further, adjust the second three-way valve so that its inlet end is connected to the first three-way valve and its outlet end is connected to the flow meter in the first gas vent flow path. Then, set the pressures of the first back pressure valve and the second back pressure valve to be the same as the carrier gas inlet pressure, such as 150 kPa. Further, adjust the multi-way valve to be connected to the gas sampling port corresponding to the (device or pipeline or sampling cylinder), and adjust the multi-way valve to connect the sampling valve to the first flow pressure reducing valve. At this time, open the root valve of the (device or pipeline or sampling cylinder) device in sequence, adjust the first flow regulating valve so that the flow meter shows 50 ml / min, and perform a quick replacement for 1 - 2 minutes. After the replacement is completed, rotate the second three-way valve so that the sample enters the quantitative loop on the gas injection quantitative valve (i.e., the six-way injection valve), and is vented through the second back pressure valve to perform sample replacement on the pipeline and the quantitative loop for 0.5 - 1 minute. Rotate the gas injection quantitative valve to the injection position, and the carrier gas will carry the sample into the chromatograph for chromatographic analysis.

[0077] After the gas injection quantitative valve completes the injection, rotate it back to the sampling position, switch the multi-way valve so that the purging inert gas enters the flow path to purge the flow path and prepare for the next injection.

[0078] Embodiment 2

[0079] The embodiment of the utility model provides a process for volatile sample injection (second flow path). Taking the analysis of liquefied petroleum gas (LPG) as an example, the main components of LPG are propane and butane, and at the same time, it contains partially dissolved methane, ethane, C5, C6, and extremely small amounts of C7 and C8 components. The boiling points of the component compounds range from -164°C (methane) to -125°C (n-octane). The specific operation steps are as follows:

[0080] First, set the temperature of the heating zone according to the highest boiling point of the sample to be measured to ensure that the volatile liquid vaporizes in the flash evaporator and maintains a gaseous state. Set the temperature of the heating zone to 120°C and wait for the temperature of the heating zone to stabilize. First, adjust the first three-way valve so that its inlet end is connected to the flash tank and its outlet end is connected to the second three-way valve; further, adjust the second three-way valve so that its inlet end is connected to the first three-way valve and its outlet end is connected to the flow meter in the first gas vent flow path. Further, adjust the multi-way valve to connect with the corresponding volatile sample sampling port (equipment or pipeline or sampling cylinder), and adjust the multi-way valve to connect the sampling valve with the second flow pressure reducing valve. Set the pressures of the first back pressure valve and the second back pressure valve to 150 kPa. Open the sampling valve (equipment or pipeline or sampling cylinder) in sequence, adjust the second flow pressure reducing valve, and set the output pressure slightly higher than the pressures of the first back pressure valve and the second back pressure valve, such as 180 kPa. Further, adjust the flow meter to make the vent flow rate 50 ml / min and perform a quick replacement for 4 - 5 minutes. After the replacement is completed, rotate the second three-way valve so that the sample enters the quantitative loop on the gas injection quantitative valve (i.e., six-way injection valve) and vents through the second back pressure valve to replace the sample in the pipeline and the quantitative loop for 0.5 - 1 minute. Rotate the gas injection quantitative valve to the injection position, and the carrier gas will carry the sample into the chromatograph for chromatographic analysis. After the gas injection quantitative valve completes the injection, rotate it back to the sampling position, switch the multi-way valve so that the purging inert gas enters the flow path to purge the flow path and prepare for the next injection.

[0081] Example Three

[0082] The embodiment of the utility model provides a process for liquid sample injection (third flow path). Taking the analysis of methanol as an example, the specific operation steps are as follows:

[0083] Adjust the multi-way valve to connect with the corresponding liquid sample sampling port (equipment or pipeline or sampling cylinder), and adjust the multi-way valve to connect the sampling valve with the flow regulating valve; further, open the sampling valve (equipment or pipeline or sampling cylinder) and the flow regulating valve in sequence to replace the sample in the pipeline and the micro liquid injection valve. The replacement volume is about 20 times the volume of the entire flow path. After the replacement is completed, rotate the micro injection valve, and the sample enters the chromatograph for analysis.

[0084] The basic principles of the present utility model have been described in conjunction with specific embodiments. However, it should be noted that the advantages, benefits, effects, etc. mentioned in the present utility model are only examples and not limitations. It cannot be considered that these advantages, benefits, effects, etc. are essential for each embodiment of the present utility model. Additionally, the specific details disclosed above are only for illustrative and easy-to-understand purposes, rather than limitations. These details do not limit the present utility model to necessarily adopt the above specific details for implementation.

[0085] The block diagrams of the devices, apparatuses, equipment, and systems involved in the present utility model are only illustrative examples and do not intend to require or imply that they must be connected, arranged, and configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these devices, apparatuses, equipment, and systems can be connected, arranged, and configured in any manner. Words such as "comprising", "including", "having", etc. are open-ended terms, meaning "including but not limited to", and can be used interchangeably with each other. The word "or" and "and" used herein refer to the word "and / or", and can be used interchangeably with each other, unless the context clearly indicates otherwise. The word "such as" used herein refers to the phrase "such as but not limited to", and can be used interchangeably with each other.

[0086] In addition, as used herein, the "or" used in the listing of items starting with "at least one" indicates a separate listing. So, for example, the listing of "at least one of A, B, or C" means A or B or C, or AB or AC or BC, or ABC (i.e., A and B and C). Furthermore, the term "exemplary" does not mean that the described examples are preferred or better than other examples.

[0087] It should also be noted that in the systems and methods of the present utility model, each component or each step can be decomposed and / or recombined. These decompositions and / or recombinations should be regarded as equivalent solutions of the present utility model.

[0088] Various changes, substitutions, and alterations to the technologies described herein can be made without departing from the teachings defined by the appended claims. In addition, the scope of the claims of the present utility model is not limited to the specific aspects of the processes, machines, manufactures, compositions of events, means, methods, and acts described above. Current or later-developed processes, machines, manufactures, compositions of events, means, methods, or acts that perform substantially the same function or achieve substantially the same result as the corresponding aspects described herein can be utilized. Thus, the appended claims include such processes, machines, manufactures, compositions of events, means, methods, or acts within their scope.

[0089] The above description of the disclosed aspects enables any person skilled in the art to make or use the present utility model. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects without departing from the scope of the present utility model. Therefore, the present utility model is not intended to be limited to the aspects shown herein, but rather to the broadest scope consistent with the principles and novel features disclosed herein.

[0090] The above description has been presented for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of the present utility model to the forms disclosed herein. Although several example aspects and embodiments have been discussed above, those skilled in the art will recognize some of their variations, modifications, alterations, additions, and subcombinations.

Claims

1. A chromatography detection system, characterized in that: The device is applied to a place with multiple sampling points to be detected, comprising: a sampling valve, a multi-way valve, a first flow path, a second flow path, a third flow path, a first detection device, and a second detection device, wherein the sampling valve has multiple sample inlets and sample outlets, the multiple sample inlets are respectively connected to corresponding sampling points to be detected, the sample outlets are connected to the inlet of the multi-way valve, the multi-way valve includes a first outlet, a second outlet, and a third outlet, the first outlet of the multi-way valve is connected to the first flow path, the second outlet of the multi-way valve is connected to the second flow path, and the third outlet of the multi-way valve is connected to the third flow path; The outlet of the first flow path and the outlet of the second flow path are respectively communicated with the first detection device, and the outlet of the third flow path is communicated with the second detection device.

2. The chromatographic detection system according to claim 1, characterized in that The first flow path includes a first flow reducing valve, and the first outlet of the multi-way valve is communicated with the inlet of the first flow reducing valve.

3. The chromatographic detection system according to claim 2, characterized in that: The second flow path includes a second flow pressure reducing valve, a flash tank and a first three-way valve, a second three-way valve and a gas sampling quantitative valve. The second outlet of the multi-way valve is communicated with the inlet of the second flow pressure reducing valve, the outlet of the second flow pressure reducing valve is communicated with the inlet of the flash tank, the outlet of the flash tank is communicated with the first inlet of the first three-way valve, the outlet of the first three-way valve is communicated with the second three-way valve, the first outlet of the second three-way valve is communicated with the inlet of the gas sampling quantitative valve, and the first outlet of the gas sampling quantitative valve is communicated with the first detection device.

4. The chromatographic detection system according to claim 3, characterized in that: The outlet of the first flow reducing valve is communicated with the second inlet of the first three-way valve.

5. The chromatographic detection system according to claim 3, characterized in that: Both ends of the flash tank are conical, and the cone angle is less than 60°.

6. The chromatographic detection system according to claim 3, characterized in that: A heat-insulating double-pass valve is also provided between the second flow pressure reducing valve and the flash tank.

7. The chromatographic detection system according to claim 3, characterized in that: The chromatographic detection system further includes a first gas venting flow path, and the second outlet of the second three-way valve is connected to the inlet of the first gas venting flow path.

8. The chromatographic detection system according to claim 7, characterized in that: The first gas venting flow path includes a flow meter, a first back pressure valve and a first one-way valve. The second outlet of the second three-way valve is connected to the inlet of the flow meter, the outlet of the flow meter is connected to the inlet of the first back pressure valve, the inlet of the first back pressure valve is connected to the inlet of the first one-way valve, and the outlet of the first one-way valve is connected to the external space.

9. The chromatographic detection system according to claim 3, characterized in that: The chromatographic detection system further includes a second gas venting flow path, the gas sampling quantitative valve has a first carrier gas inlet, and the second outlet of the gas sampling quantitative valve is communicated with the second gas venting flow path.

10. The chromatographic detection system according to claim 9, characterized in that: The second gas venting flow path includes a second back pressure valve and a second one-way valve. The second outlet of the gas sampling quantitative valve is connected to the inlet of the second back pressure valve, the outlet of the second back pressure valve is connected to the inlet of the second one-way valve, and the outlet of the second one-way valve is connected to the external space.

11. The chromatographic detection system according to claim 1, characterized in that: The third flow path includes a flow regulating valve and a trace liquid injection valve, the third outlet of the multi-way valve is connected to the inlet of the flow regulating valve, the outlet of the flow regulating valve is connected to the inlet of the trace liquid injection valve, and the first outlet of the trace liquid injection valve is connected to the second detection device.

12. The chromatographic detection system according to claim 11, characterized in that: The micro-liquid injection valve also has a liquid venting outlet and a second carrier gas inlet.

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