Condensation pre-concentration equipment for trace organic gas and control method of condensation pre-concentration equipment

Abstract

The invention provides condensation pre-concentration equipment for trace organic gas and a control method of the condensation pre-concentration equipment. The condensation pre-concentration equipment comprises a first valve assembly and a second valve assembly. A first port of the first valve assembly is connected with a sixth port of the second valve assembly, a first trapping trap is arranged between a second port and a fifth port of the first valve assembly, a third port of the first valve assembly is connected with an emptying port, a fourth port of the first valve assembly is connected with an external sample injection gas port after passing through a first dryer, and the sixth port of the first valve assembly is connected with a carrier gas port through a first electric control valve; a first port of the second valve assembly is emptied, a second trapping trap is arranged between the second port and a fifth port of the second valve assembly, the second trapping trap is isolated when the second valve assembly is located at the isolation position, a third port of the second valve assembly is connected with the carrier gas port through a second electric control valve, and a fourth port of the second valve assembly is connected with the chromatographic column; and the main controller is connected with the first valve assembly, the second valve assembly, the first trapping trap, the second trapping trap, the first electric control valve and the second electric control valve. The equipment has the effects of miniaturization and easy movement.

Description

Technical Field

[0001] The present application relates to the technical field of volatile gas collection and analysis, and in particular to a condensation pre-concentration device for trace organic gases and a control method thereof. Background Art

[0002] Trace organic gas refers to organic gas substances with extremely low content in the air, and the equipment for detecting it needs to have high sensitivity. For example, the condensation pre-concentration equipment and treatment method for trace organic gas disclosed in the existing patent document CN 119926096 A, wherein the equipment includes a water vapor removal device, a carbon dioxide removal device, a trap device, a temperature control device, a valve group device, a carrier gas input device and an analysis device. Figure 1 As shown, the valve group device includes six valve assemblies, which take up a large space. Such a large number of valve assemblies makes the overall volume of the equipment too large, and also brings more inconvenience to the connection design of the pipeline, which does not meet the current demand for miniaturization and intelligence of the equipment. Summary of the Invention

[0003] The technical problem to be solved by the present application is that the trace organic gas detection solution in the prior art is too large in size and difficult in pipeline design, and thus provides a condensation pre-concentration device for trace organic gas and a control method thereof.

[0004] In a first aspect, the technical solution of the present application provides a condensation pre-concentration device for trace organic gases, comprising: A first valve assembly and a second valve assembly, wherein each of the first valve assembly and the second valve assembly comprises six ports, and the second valve assembly comprises an isolation position, wherein the second port and the fifth port of the second valve assembly are isolated when the second valve assembly is in the isolation position, wherein: The first valve assembly, whose first port is connected to the sixth port of the second valve assembly, a first trap is set between its second port and its fifth port, its third port is connected to the exhaust port, its fourth port is connected to the external sample gas port after passing through the first dryer, and its sixth port is connected to the carrier gas port through the first electronically controlled valve; The second valve assembly has a first port that is evacuated, a second trap disposed between the second port and the fifth port thereof, the second trap being isolated when the second valve assembly is in the isolation position, a third port connected to the carrier gas port via a second electrically controlled valve, and a fourth port connected to the chromatographic column; A main controller is connected to the first valve assembly, the second valve assembly, the first trap, the second trap, the first electrically controlled valve, and the second electrically controlled valve.

[0005] Preferably, in the condensation pre-concentration equipment for trace organic gases, the first valve assembly includes an isolation position, and the first trap is isolated when the first valve assembly is in the isolation position.

[0006] Preferably, the condensation pre-concentration equipment for trace organic gases further comprises: a flow controller, disposed between the third port of the first valve assembly and the drain port; the flow controller is connected to the main controller; The first pressure sensor is disposed between the third port of the first valve assembly and the flow controller, and the first pressure sensor is connected to the main controller.

[0007] Preferably, the condensation pre-concentration equipment for trace organic gases further comprises: a second dryer, disposed between the fifth port of the first valve group and the first trap; a trap flow meter, disposed at the first port of the second valve assembly; The second pressure sensor is arranged between the first port of the second valve assembly and the capture trap flowmeter; the second pressure sensor is connected to the main controller.

[0008] Preferably, the condensation pre-concentration device for trace organic gas further comprises a third valve assembly, wherein the third valve assembly is arranged between the first valve assembly and the second valve assembly, wherein: The third valve assembly includes ten ports, a first port thereof is connected to the fourth port of the second valve assembly, a second port thereof is connected to the chromatographic column, an additional chromatographic column is arranged between the third port and the tenth port thereof, a fourth port thereof is connected to the carrier gas port after passing through a third electrically controlled valve, a fifth port thereof is connected to a column backflush, a carbon dioxide filter is arranged between the sixth port thereof and the ninth port thereof, a seventh port thereof is connected to the first port of the first valve assembly, and a eighth port thereof is connected to the sixth port of the second valve assembly; The controlled end of the third valve assembly is connected to the main controller.

[0009] Preferably, the condensation pre-concentration equipment for trace organic gases further comprises: A third pressure sensor is disposed at the carrier gas port and is connected to the main controller.

[0010] In a second aspect, the present application provides a method for controlling a condensation pre-concentration device for trace organic gases, comprising: a sampling step of controlling the first valve assembly to communicate its second port with its third port and its fourth port with its fifth port, so that the input gas passes through the first dryer, the fourth port of the first valve assembly, the fifth port of the first valve assembly, and the second dryer and then enters the first trap; the temperature of the first trap is reduced to liquefy the target substance in the input gas to obtain treated gas; the treated gas is discharged through the second port of the first valve assembly and the third port of the first valve assembly; an impurity removal step, controlling the first valve assembly to communicate with its first port and its second port, and its fifth port and its sixth port; controlling the first port and the sixth port of the second valve assembly to communicate with each other; controlling the first electrically controlled valve to open; allowing the carrier gas to enter the first trap after passing through the first electrically controlled valve, the sixth port of the first valve assembly, the fifth port of the first valve assembly, and the second dryer; and after the first trap is heated, the impurities are converted into gaseous state and discharged from the first trap along with the carrier gas, and then discharged through the second port of the first valve assembly, the first port of the first valve assembly, the sixth port of the second valve assembly, and the first port of the second valve assembly. a transfer step, controlling the second valve assembly to operate so that its first port is connected to its second port and its fifth port is connected to its sixth port; the carrier gas enters the first trap after passing through the first electrically controlled valve, the sixth port of the first valve assembly, the fifth port of the first valve assembly, and the second dryer; after the first trap is heated, the target substance is converted into a gaseous state and discharged from the first trap along with the carrier gas, and then enters the second trap after passing through the second port of the first valve assembly, the first port of the first valve assembly, the sixth port of the second valve assembly, and the fifth port of the second valve assembly; after the second trap is cooled so that the target substance is liquefied, the remaining gas is discharged from the second trap after passing through the second port of the second valve assembly and the first port of the second valve assembly; an analysis step, controlling the second valve assembly to be in an isolation position, and heating the second trap after being isolated to convert the target substance into a gaseous state; In the injection step, the second valve assembly is controlled to operate so that its first port is connected to its second port and its fourth port is connected to its fifth port; the second electrically controlled valve is controlled to be opened and then reconnected to the second trap; the carrier gas enters the second trap after passing through the second electrically controlled valve, the first port of the second valve assembly, and the second port of the second valve assembly, carrying the target substance converted into gaseous state, and enters the chromatographic column after passing through the fifth port of the second valve assembly and the fourth port of the second valve assembly to obtain the separation result of the target substance.

[0011] Preferably, in the control method of the condensation pre-concentration device for trace organic gas, when the device includes a third valve assembly: The impurity removal step further includes: controlling the seventh port of the third valve assembly to communicate with its eighth port, at which time the carrier gas enters the first trap after passing through the first electrically controlled valve, the sixth port of the first valve assembly, the fifth port of the first valve assembly, and the second dryer; after the first trap is heated, the impurities are converted into gaseous state and discharged from the first trap along with the carrier gas, and then discharged through the second port of the first valve assembly, the first port of the first valve assembly, the seventh port of the third valve assembly, the eighth port of the third valve assembly, the sixth port of the second valve assembly, and the first port of the second valve assembly; In the transfer step, if the temperature of the first trap does not reach the boiling point of carbon dioxide in the impurity removal step or the transfer step is not performed for the first time, the carrier gas enters the first trap after passing through the first electrically controlled valve, the sixth port of the first valve assembly, the fifth port of the first valve assembly, and the second dryer. After the temperature of the first trap is increased, the target substance is converted into a gaseous state and discharged from the first trap along with the carrier gas. The target substance is then transferred to the second trap through the second port of the first valve assembly, the first port of the first valve assembly, the seventh port of the third valve assembly, the eighth port of the third valve assembly, the sixth port of the second valve assembly, and the fifth port of the second valve assembly. After the temperature of the second trap is reduced to liquefy the target substance, the remaining gas is discharged from the second trap through the second port of the second valve assembly and the first port of the second valve assembly. The injection step also includes controlling the action of the third valve assembly so that its first port is connected to its second port; the carrier gas enters the second capture trap after passing through the second electrically controlled valve, the first port of the second valve assembly, and the second port of the second valve assembly, and then carries the target substance converted into gaseous state, and enters the chromatographic column after passing through the first port of the third valve assembly and the second port of the third valve assembly to obtain the separation result of the target substance.

[0012] Preferably, the control method of the condensation pre-concentration equipment for trace organic gases is: If the temperature of the first trap is raised to above the boiling point of carbon dioxide in the impurity removal step, and the transfer step is performed for the first time, the transfer step further includes controlling the action of the third valve assembly so that its sixth port is connected to its seventh port and its eighth port is connected to its ninth port; the carrier gas enters the first trap after passing through the first electrically controlled valve, the sixth port of the first valve assembly, the fifth port of the first valve assembly, and the second dryer; after the first trap is heated, the target substance is converted into gaseous state and discharged from the first trap along with the carrier gas, and then enters the carbon dioxide filter through the second port of the first valve assembly, the first port of the first valve assembly, the seventh port of the third valve assembly, and the sixth port of the third valve assembly to filter the carbon dioxide, and then transfers to the second trap through the sixth port of the second valve assembly and the fifth port of the second valve assembly; after the second trap is cooled to liquefy the target substance, the remaining gas is discharged from the second trap through the second port of the second valve assembly and the first port of the second valve assembly.

[0013] Preferably, the control method of the condensation pre-concentration equipment for trace organic gases is: The injection step is transformed into the following method: Control the second valve assembly so that its second port is connected to its third port, and its fourth port is connected to its fifth port; control the movement of the third valve assembly so that its first port is connected to its tenth port, and its second port is connected to its third port; control the second electrically controlled valve to open; the carrier gas enters the second trap after passing through the second electrically controlled valve, the third port of the second valve assembly, and the second port of the second valve assembly, and then carries the target substance converted into gaseous state; passes through the fifth port of the second valve assembly, the fourth port of the second valve assembly, the first port of the third valve assembly, and the tenth port of the third valve assembly, and then passes through the additional chromatographic column to obtain additional separation results; then passes through the third port of the third valve assembly and the second port of the third valve assembly, and then enters the chromatographic column to obtain the separation result of the target substance.

[0014] Compared with the existing technology, the above technical solution provided by this application has the following technical effects: The technical solution provided in this application enables sampling, impurity removal, analysis, injection, and separation of target substances from trace organic gases through the coordination of only two valve assemblies. Compared to existing technologies, this solution reduces the number of valve assemblies, thereby simplifying the piping design and reducing the overall device size. This makes the trace organic gas condensation and pre-concentration device more compatible with current user demands for miniaturized trace organic gas condensation and pre-concentration equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1This is a schematic structural diagram of a condensation and pre-concentration device for trace organic gases according to one embodiment of the present application; Figure 2 This is a schematic structural diagram of a condensation and pre-concentration device for trace organic gases according to another embodiment of the present application; Figure 3 This is a state diagram of the condensation pre-concentration device for trace organic gases according to one embodiment of the present application when performing a sampling step; Figure 4a This is a state diagram of the condensation pre-concentration device for trace organic gas according to one embodiment of the present application when it includes two valve assemblies and performs an impurity removal step; Figure 4b This is a state diagram of the trace organic gas condensation pre-concentration device according to one embodiment of the present application when performing the impurity removal step when the device comprises three valve assemblies; Figure 5a This is a state diagram of the condensation pre-concentration device for trace organic gas according to one embodiment of the present application when the device comprises two valve assemblies and performs a transfer step; Figure 5b This is a state diagram of the condensation pre-concentration device for trace organic gas according to one embodiment of the present application when the device comprises three valve assemblies and performs a transfer step; Figure 6 This is a state diagram of the condensation pre-concentration device for trace organic gases according to one embodiment of the present application when performing a transfer step while removing carbon dioxide; Figure 7 This is a state diagram of the isolated second trap of the condensation pre-concentration device for trace organic gases according to one embodiment of the present application when performing the analysis step; Figure 8a This is a state diagram of the condensation pre-concentration device for trace organic gases according to one embodiment of the present application when performing a sampling step when the device comprises two valve assemblies; Figure 8b This is a state diagram of the condensation pre-concentration device for trace organic gases according to one embodiment of the present application when performing a sampling step when the device comprises three valve assemblies; Figure 9 This is a state diagram of another embodiment of the trace organic gas condensation pre-concentration device according to the present application when performing two chromatographic column separations during the injection step; Figure 10 This is a schematic structural diagram of the drying gas branch circuit according to one embodiment of the present application. DETAILED DESCRIPTION

[0016] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections, electrical connections, or mutual communication; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to internal communication between two components or the interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0017] This embodiment provides a condensation pre-concentration device for trace organic gases, such as Figure 1 As shown, including: A first valve assembly V1 and a second valve assembly V2, wherein each of the first valve assembly V1 and the second valve assembly V2 includes six ports, and the second valve assembly V2 includes an isolation position, wherein the second port and the fifth port of the second valve assembly V2 are isolated when the second valve assembly V2 is in the isolation position, wherein: The first valve assembly V1 has a first port connected to the sixth port of the second valve assembly V2, a first trap B1 is set between the second port and the fifth port, a third port is connected to the exhaust port P, a fourth port is connected to the external sample gas port YQ after passing through the first dryer G1, and a sixth port is connected to the carrier gas port GQ through the first electronically controlled valve EPC1; The first port of the second valve assembly V2 is emptied, and a second trap B2 is set between its second port and its fifth port. When the second valve assembly V2 is in the isolation position, the second trap B2 is isolated. The third port of the second valve assembly V2 is connected to the carrier gas port GQ via the second electric control valve EPC2, and its fourth port is connected to the chromatographic column SP; in addition, as shown in the figure, as a feasible solution, the first port of the second valve assembly V2 can also be connected to the trap flowmeter BS to realize trap flow monitoring.

[0018] A main controller (not shown in the figure) is connected to the first valve assembly V1, the second valve assembly V2, the first trap B1, the second trap B2, the first electrically controlled valve EPC1 and the second electrically controlled valve EPC2.

[0019] Under operator control, the master controller can send control commands to various components, such as valves and traps, to control their operation. Therefore, it is sufficient for the master controller to communicate with each component to be controlled. The master controller can be a PLC controller within the device or a computer equipped with control software and an operation panel.

[0020] The temperature of the first trap B1 and the second trap B2 is adjustable, so that the vaporization, liquefaction and other operations of the substances inside them can be realized. At that time, the temperature of the first trap B1 and the second trap B2 can be regulated according to the critical temperature of the state change of the substance to be vaporized or liquefied. For example, if the first trap B1 needs to liquefy water vapor, its temperature can be controlled within the range of -50~-70℃. The method of controlling the temperature of the trap is similar to the control method in the existing patent document cited in the background technology (this solution is actually a technical solution proposed by the inventor of this case). The temperature setting and control of the trap will not be repeated in this solution. Because the inventor found that the solution in the existing patent document was too complicated and difficult to miniaturize, and it was even more difficult to use it as a mobile device, the improvement of the solution of this application is to simplify the equipment, design more reasonable pipeline connections, reduce valve components, and reduce the size of the equipment so that it can be conveniently used as a mobile device.

[0021] like Figure 1 As shown, compared to the existing technical solutions that require six valve assemblies, the solution in this application only requires the cooperation of two valve assemblies to achieve trace organic gas sampling, impurity removal, analysis, injection, and separation results of the target substance. Compared with the existing technology, the reduction of multiple valve assemblies simplifies the piping design of the entire device and reduces the overall device size, making the trace organic gas condensation pre-concentration device more meet the current user demand for miniaturization of trace organic gas condensation pre-concentration equipment.

[0022] In addition, the first valve assembly V1 may also be the same as the second valve assembly V2 and have an isolation position. When the first valve assembly V1 is in the isolation position, the second port and the fifth port of the first valve assembly V1 are isolated, and the first trap B1 is in an isolated state.

[0023] like Figure 1 As shown, the condensation pre-concentration device for trace organic gases in the present application further includes a flow controller L1, which is disposed between the third port of the first valve assembly V1 and the exhaust port P. The flow controller L1 is connected to the main controller. Specifically, the flow controller L1 is capable of controlling the exhaust flow rate at the exhaust port P, both sending the flow rate to the main controller and adjusting the flow rate according to the main controller.

[0024] Furthermore, if Figure 2 As shown, the condensation pre-concentration equipment for trace organic gases also includes: The third valve assembly V3 is disposed between the first valve assembly V1 and the second valve assembly V2. The third valve assembly V3 includes ten ports: its first port is connected to the fourth port of the second valve assembly V2, its second port is connected to the chromatographic column SP, an additional chromatographic column FSP is located between its third and tenth ports, its fourth port is connected to the carrier gas port GQ via a third electrically controlled valve EPC3, its fifth port is connected to the column backflush ZFC, a carbon dioxide filter Gc is located between its sixth and ninth ports, its seventh port is connected to the first port of the first valve assembly V1, and its eighth port is connected to the sixth port of the second valve assembly V2. The controlled end of the third valve assembly V3 is connected to the main controller. By controlling the positions of the three valve assemblies and opening and closing the control valves connected to different ports of the three valve assemblies, different gas pathways can be achieved.

[0025] The third valve assembly V3 is designed to accommodate the addition of an additional chromatographic column (FSP), a carbon dioxide filter (Gc), and a column backflush (ZFC). If these components are required to be connected to the gas line, the third valve assembly V3 can be controlled to connect them. Otherwise, the third valve assembly V3 can be controlled to maintain connectivity.

[0026] like Figure 2 As shown, the condensation pre-concentration device for trace organic gas further includes a first pressure sensor PI1, which is arranged between the third port of the first valve assembly V1 and the flow controller L1, and the first pressure sensor PI1 is connected to the main controller.

[0027] The second dryer G2 is disposed between the fifth port of the first valve group V1 and the first trap B1.

[0028] The second pressure sensor PI2 is provided between the first port of the second valve assembly V2 and the capture trap flow meter BS; the second pressure sensor PI2 is connected to the main controller.

[0029] The third pressure sensor PI3 is disposed at the carrier gas port GQ and is connected to the main controller.

[0030] The fourth pressure sensor PI4 is provided between the external gas injection port YQ and the first dryer G1.

[0031] The filter GL is provided between the first pressure sensor PI1 and the flow controller L1. An air pump may also be provided at the exhaust port P to assist in improving exhaust efficiency.

[0032] In the above scheme, trace organic gas collection and chromatographic detection can be achieved by controlling the position status of different valve components, which can effectively reduce the size of the equipment and is conducive to its miniaturization and mobility.

[0033] The present application also provides a method for controlling a condensation pre-concentration device for trace organic gases, comprising the following steps: (1) Sampling steps like Figure 3 As shown, the gas flow is indicated by the blue pipeline. The first valve assembly V1 is controlled to connect its second port to its third port, and its fourth port to its fifth port. The sample gas passes through the first dryer G1, the fourth port of the first valve assembly V1, the fifth port of the first valve assembly V1, and the second dryer G2 before entering the first trap B1. The temperature of the first trap B1 is reduced, liquefying the target substance in the sample gas to obtain treated gas. The treated gas is discharged through the second port of the first valve assembly V1 and the third port of the first valve assembly V1. In the sampling step, only the first valve assembly V1 is required. Whether the equipment includes two or three valve assemblies does not affect the gas path implementation in this step.

[0034] (2) Impurity removal steps like Figure 4a As shown, the gas flow is indicated by the blue pipeline. In this case, the equipment includes two valve assemblies. The first valve assembly V1 is controlled to connect its first port to its second port and its fifth port to its sixth port. The second valve assembly V2 is controlled to connect its first port to its sixth port. The first electrically controlled valve EPC1 is controlled to open. The carrier gas passes through the first electrically controlled valve EPC1, the sixth port of the first valve assembly V1, the fifth port of the first valve assembly V1, and the second dryer G2 before entering the first trap B1. After heating, the impurities in the first trap B1 transform into gaseous form and are discharged along with the carrier gas. The impurities then pass through the second port of the first valve assembly V1, the first port of the first valve assembly V1, the sixth port of the second valve assembly V2, the first port of the second valve assembly V2, and finally through the trap flowmeter BS. As previously mentioned, the trap flowmeter BS may or may not be provided. If the trap flowmeter BS is not provided, the gas is exhausted through the first port of the second valve assembly V2. It can be understood that the following embodiments of the present application are described by taking the setting of the capture trap flowmeter BS as an example, and are not intended to limit the solution itself.

[0035] like Figure 4bAs shown in the figure, the gas flow is indicated by the blue pipeline. In this case, the equipment includes three valve assemblies. The first valve assembly V1 is controlled to connect its first port with its second port and its fifth port with its sixth port. The first port of the second valve assembly V2 is controlled to connect its sixth port. The seventh port of the third valve assembly V3 is controlled to connect its eighth port. In this case, the third valve assembly V3 is directly connected and has no effect on the gas flow. The first electrically controlled valve EPC1 is controlled to open. After the carrier gas is output from the carrier gas port GQ, it passes through the first electrically controlled valve EPC1, the sixth port of the first valve assembly V1, the fifth port of the first valve assembly V1, the second dryer G2, and then enters the first trap B1. After the first trap B1 heats up, the impurities are converted into gaseous state and discharged from the first trap B1 along with the carrier gas. The impurities then pass through the second port of the first valve assembly V1, the first port of the first valve assembly V1, the seventh port of the third valve assembly V3, the eighth port of the third valve assembly V3, the sixth port of the second valve assembly V2, the first port of the second valve assembly V2, and finally through the trap flowmeter BS.

[0036] (3) Transfer steps like Figure 5a As shown, the first transfer gas flow is shown as the blue line, and in this case the equipment includes two valve assemblies.

[0037] If the temperature of the first trap B1 does not reach the boiling point of carbon dioxide in the impurity removal step or the transfer step is not performed for the first time, the carrier gas enters the first trap B1 after passing through the first electrically controlled valve EPC1, the sixth port of the first valve assembly V1, the fifth port of the first valve assembly V1, and the second dryer G2. After the first trap B1 is heated, the target substance is converted into gaseous state and discharged from the first trap B1 along with the carrier gas. The target substance is then transferred to the second trap B2 through the second port of the first valve assembly V1, the first port of the first valve assembly V1, the seventh port of the third valve assembly V3, the eighth port of the third valve assembly V3, the sixth port of the second valve assembly V2, and the fifth port of the second valve assembly V2. After the second trap B2 is cooled to liquefy the target substance, the remaining gas is discharged from the second trap B2 through the second port of the second valve assembly V2, the first port of the second valve assembly V2, and the trap flowmeter BS. Since the temperature of the first trap B1 does not reach the boiling point of carbon dioxide during the impurity removal step, the transferred gas does not contain carbon dioxide, and therefore, the carbon dioxide filter Gc is not required. If this is not the first transfer step, carbon dioxide has already been filtered in the previous transfer step, and the gas transferred this time does not contain carbon dioxide, therefore, the carbon dioxide filter Gc is not required.

[0038] like Figure 5bAs shown, the transfer gas flow is indicated by the blue pipeline. In this case, the equipment includes three valve assemblies. The state of the first valve assembly V1 is the same as that in the impurity removal step. The second valve assembly V2 is controlled to connect its first port with its second port and its fifth port with its sixth port. The carrier gas enters the first trap B1 after passing through the first electrically controlled valve EPC1, the sixth port of the first valve assembly V1, the fifth port of the first valve assembly V1, and the second dryer G2. After heating up, the target substance transforms into a gaseous state and exits the first trap B1 along with the carrier gas. It then passes through the second port of the first valve assembly V1, the first port of the first valve assembly V1, the seventh port of the third valve assembly V3, the eighth port of the third valve assembly V3, the sixth port of the second valve assembly V2, and the fifth port of the second valve assembly V2 before entering the second trap B2. After cooling down the second trap B2, the target substance liquefies, and the remaining gas exits the second trap B2 through the second port of the second valve assembly V2, the first port of the second valve assembly V2, and the trap flowmeter BS. During this process, the third valve assembly V3 does not actually change the gas path, and the gas is not filtered through the carbon dioxide filter Gc.

[0039] If the temperature of the first trap B1 is raised to above the boiling point of carbon dioxide in the impurity removal step and the transfer step is performed for the first time, then in the transfer step, if Figure 6 As shown, the flow direction of the second transfer gas is shown by the blue pipeline. During this process, the third valve assembly V3 is controlled to operate so that its sixth port is connected to its seventh port and its eighth port is connected to its ninth port. Then, the carrier gas enters the first trap B1 after passing through the first electrically controlled valve EPC1, the sixth port of the first valve assembly V1, the fifth port of the first valve assembly V1, and the second dryer G2. After the first trap B1 is heated, the target substance is converted into gaseous state and discharged from the first trap B1 along with the carrier gas. After passing through the second port of the first valve assembly V1, the first port of the first valve assembly V1, the seventh port of the third valve assembly V3, and the sixth port of the third valve assembly V3, it enters the carbon dioxide filter Gc to filter the carbon dioxide. After passing through the sixth port of the second valve assembly V2 and the fifth port of the second valve assembly V2, it enters the second trap B2. After the second trap B2 is cooled to liquefy the target substance, the remaining gas is discharged from the second trap B2 after passing through the second port of the second valve assembly V2, the first port of the second valve assembly V2, and the trap flowmeter BS. Because the temperature of the first trap B1 is raised to above the boiling point of carbon dioxide in the impurity removal step, and the transfer step is performed for the first time, the transferred gas contains carbon dioxide, so a carbon dioxide filtering operation is performed in this step.

[0040] As mentioned above, the first valve assembly V1 may also have an isolation position. During the transfer step, the first trap B1 can be isolated and heated by adjusting the first valve assembly V1 to the isolation position. When all the gases to be transferred are vaporized, the first trap B1 is repeatedly connected to the gas passage to transfer the vaporized gases in a centralized manner.

[0041] (4) Parsing steps like Figure 7 As shown, the second trap B2 is controlled to be detached and heated to convert the target substance into a gaseous state. Because the second trap B2 is detachably installed in the device, it can be removed to isolate it from the gas path and heated in isolation. Once the target substance inside has been converted into a gaseous state, it can be connected to the device. This allows the target substance to flow more quickly with the carrier gas.

[0042] (5) Injection steps like Figure 8a Figure 1 illustrates one implementation of the gas path for the injection step, where the device includes two valve assemblies. The second valve assembly V2 is controlled to connect its first port to its second port, and its fourth port to its fifth port. The second electrically controlled valve EPC2 is then opened and reconnected to the second trap B2. The carrier gas enters the second trap B2 after passing through the second electrically controlled valve EPC2, the first port of the second valve assembly V2, and the second port of the second valve assembly V2. The carrier gas then enters the second trap B2, carrying the target substance in a gaseous state. The carrier gas then passes through the fifth port of the second valve assembly V2 and the fourth port of the second valve assembly V2, before entering the chromatographic column SP to separate the target substance.

[0043] like Figure 8b As shown, the apparatus now includes three valve assemblies. If the target substance previously transferred can be accurately separated by passing through the chromatographic column SP, the second valve assembly V2 is controlled to operate, connecting its first port to its second port and its fourth port to its fifth port. The third valve assembly V3 is controlled to operate, connecting its first port to its second port. The second electrically controlled valve EPC2 is controlled to open and reconnect to the second trap B2. The carrier gas enters the second trap B2 after passing through the second electrically controlled valve EPC2, the first port of the second valve assembly V2, and the second port of the second valve assembly V2. The carrier gas then enters the second trap B2, carrying the gaseous target substance. The carrier gas then passes through the first port of the third valve assembly V3 and the second port of the third valve assembly V3, then enters the chromatographic column SP to obtain the target substance separation results, which are ultimately analyzed by the mass spectrometer ZP. In this case, the target substance separation requirement can be achieved by a single chromatographic column, so the additional chromatographic column FSP is not connected in this step.

[0044] If the target substance transferred in the previous step cannot be accurately separated by the chromatographic column SP, an additional chromatographic column FSP is required. Figure 9 As shown, this is the gas path implementation method of the second injection step, controlling the second valve component V2 so that its second port is connected to its third port, and its fourth port is connected to its fifth port; controlling the movement of the third valve component V3 so that its first port is connected to its tenth port, and its second port is connected to its third port; controlling the second electrically controlled valve EPC2 to open; the carrier gas enters the second trap B2 after passing through the second electrically controlled valve EPC2, the third port of the second valve component V2, and the second port of the second valve component V2, and then carries the target substance converted into gaseous state, passes through the fifth port of the second valve component V2, the fourth port of the second valve component V2, the first port of the third valve component V3, and the tenth port of the third valve component V3, and then passes through the additional chromatographic column FSP to obtain additional separation results, and then passes through the third port of the third valve component V3 and the second port of the third valve component V3 to enter the chromatographic column SP to obtain the separation result of the target substance, and finally analyzes it using the mass spectrometer ZP. Since the boiling point of the target substance exceeds the set range, a single chromatographic column cannot accurately separate the substances at this time. Therefore, in this step, the position of the third valve assembly V3 is changed and an additional chromatographic column FSP is connected. The two chromatographic columns are used to cooperate to complete the separation of multiple substances with different separation requirements.

[0045] In the above scheme, whether the target substance needs to be connected to the additional chromatographic column FSP can be judged based on experience. The additional chromatographic column FSP and the chromatographic column SP can be used to separate different types of substances. When the target substance contains substances that are within the applicable scope of the additional chromatographic column FSP, connecting the additional chromatographic column FSP for pre-separation can ensure the separation effect.

[0046] In some embodiments, column backflush can be performed on the gas circuit by changing the connectivity of the third valve assembly V3. The third port of the third valve assembly V3 is connected to its fourth port, the fifth port is connected to its sixth port, and the ninth port is connected to its tenth port. The third electrically controlled valve EPC3 is then opened. The carrier gas passes through the third electrically controlled valve EPC3, the fourth port of the third valve assembly V3, the third port of the third valve assembly V3, the additional chromatographic column, the tenth port of the third valve assembly V3, and the ninth port of the third valve assembly V3 before entering the carbon dioxide filter Gc. The carrier gas then passes through the sixth port of the third valve assembly V3, the fifth port of the third valve assembly V3, and finally enters the column backflush instrument ZFC before being discharged, thereby cleaning the carbon dioxide filter Gc.

[0047] like Figure 10As shown, the device of the present application also includes a dryer gas branch, which includes a dry gas port GZQ and a fifth pressure sensor PI5, a dry gas solenoid valve GZF, a dry gas regulating valve GZ1, a third dryer G3 and a dry gas flow meter L2 connected in sequence. The above scheme can provide dry gas for the device, and can be connected to the pipeline requiring dry gas according to the scenario.

[0048] Those skilled in the art will appreciate that the present invention is not limited to the foregoing embodiments. The foregoing embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A condensation pre-concentration device for trace organic gases, characterized in that: include: A first valve assembly and a second valve assembly, wherein each of the first valve assembly and the second valve assembly comprises six ports, and the second valve assembly comprises an isolation position, wherein the second port and the fifth port of the second valve assembly are isolated when the second valve assembly is in the isolation position, wherein: The first valve assembly, whose first port is connected to the sixth port of the second valve assembly, a first trap is set between its second port and its fifth port, its third port is connected to the exhaust port, its fourth port is connected to the external sample gas port after passing through the first dryer, and its sixth port is connected to the carrier gas port through the first electronically controlled valve; The second valve assembly has a first port that is evacuated, a second trap disposed between the second port and the fifth port thereof, the second trap being isolated when the second valve assembly is in the isolation position, a third port connected to the carrier gas port via a second electrically controlled valve, and a fourth port connected to the chromatographic column; A main controller is connected to the first valve assembly, the second valve assembly, the first trap, the second trap, the first electrically controlled valve, and the second electrically controlled valve.

2. The condensation pre-concentration equipment for trace organic gases according to claim 1, characterized in that: The first valve assembly includes an isolation position, and the first trap is isolated when the first valve assembly is in the isolation position.

3. The condensation pre-concentration equipment for trace organic gases according to claim 2, characterized in that: Also includes: a flow controller, disposed between the third port of the first valve assembly and the drain port; The flow controller is connected to the main controller; The first pressure sensor is disposed between the third port of the first valve assembly and the flow controller, and the first pressure sensor is connected to the main controller.

4. The condensation pre-concentration equipment for trace organic gases according to claim 1, characterized in that: Also includes: a second dryer, disposed between the fifth port of the first valve group and the first trap; a trap flow meter, disposed at the first port of the second valve assembly; The second pressure sensor is arranged between the first port of the second valve assembly and the capture trap flowmeter; the second pressure sensor is connected to the main controller.

5. The condensation pre-concentration equipment for trace organic gases according to any one of claims 1 to 4, characterized in that: The invention further comprises a third valve assembly, wherein the third valve assembly is disposed between the first valve assembly and the second valve assembly, wherein: The third valve assembly includes ten ports, a first port thereof is connected to the fourth port of the second valve assembly, a second port thereof is connected to the chromatographic column, an additional chromatographic column is arranged between the third port and the tenth port thereof, a fourth port thereof is connected to the carrier gas port after passing through a third electrically controlled valve, a fifth port thereof is connected to a column backflush, a carbon dioxide filter is arranged between the sixth port thereof and the ninth port thereof, a seventh port thereof is connected to the first port of the first valve assembly, and a eighth port thereof is connected to the sixth port of the second valve assembly; The controlled end of the third valve assembly is connected to the main controller.

6. The condensation pre-concentration equipment for trace organic gases according to claim 5, characterized in that: Also includes: A third pressure sensor is disposed at the carrier gas port and is connected to the main controller.

7. A control method for a condensation pre-concentration device for trace organic gases, characterized in that: include: a sampling step of controlling the first valve assembly to communicate its second port with its third port and its fourth port with its fifth port, so that the input gas passes through the first dryer, the fourth port of the first valve assembly, the fifth port of the first valve assembly, and the second dryer and then enters the first trap; the temperature of the first trap is reduced to liquefy the target substance in the input gas to obtain treated gas; the treated gas is discharged through the second port of the first valve assembly and the third port of the first valve assembly; an impurity removal step, controlling the first valve assembly to communicate with its first port and its second port, and its fifth port and its sixth port; controlling the first port and the sixth port of the second valve assembly to communicate with each other; controlling the first electrically controlled valve to open; allowing the carrier gas to enter the first trap after passing through the first electrically controlled valve, the sixth port of the first valve assembly, the fifth port of the first valve assembly, and the second dryer; and after the first trap is heated, the impurities are converted into gaseous state and discharged from the first trap along with the carrier gas, and then discharged through the second port of the first valve assembly, the first port of the first valve assembly, the sixth port of the second valve assembly, and the first port of the second valve assembly. a transfer step, controlling the second valve assembly to operate so that its first port is connected to its second port and its fifth port is connected to its sixth port; the carrier gas enters the first trap after passing through the first electrically controlled valve, the sixth port of the first valve assembly, the fifth port of the first valve assembly, and the second dryer; after the first trap is heated, the target substance is converted into a gaseous state and discharged from the first trap along with the carrier gas, and then enters the second trap after passing through the second port of the first valve assembly, the first port of the first valve assembly, the sixth port of the second valve assembly, and the fifth port of the second valve assembly; after the second trap is cooled so that the target substance is liquefied, the remaining gas is discharged from the second trap after passing through the second port of the second valve assembly and the first port of the second valve assembly; an analysis step, controlling the second valve assembly to be in an isolation position, and heating the second trap after being isolated to convert the target substance into a gaseous state; In the injection step, the second valve assembly is controlled to operate so that its first port is connected to its second port and its fourth port is connected to its fifth port; the second electrically controlled valve is controlled to be opened and then reconnected to the second trap; the carrier gas enters the second trap after passing through the second electrically controlled valve, the first port of the second valve assembly, and the second port of the second valve assembly, carrying the target substance converted into gaseous state, and enters the chromatographic column after passing through the fifth port of the second valve assembly and the fourth port of the second valve assembly to obtain the separation result of the target substance.

8. The control method for the condensation pre-concentration equipment of trace organic gas according to claim 7, characterized in that: When the apparatus includes a third valve assembly: The impurity removal step further includes: controlling the seventh port of the third valve assembly to communicate with its eighth port, at which time the carrier gas enters the first trap after passing through the first electrically controlled valve, the sixth port of the first valve assembly, the fifth port of the first valve assembly, and the second dryer; after the first trap is heated, the impurities are converted into gaseous state and discharged from the first trap along with the carrier gas, and then discharged through the second port of the first valve assembly, the first port of the first valve assembly, the seventh port of the third valve assembly, the eighth port of the third valve assembly, the sixth port of the second valve assembly, and the first port of the second valve assembly; In the transfer step, if the temperature of the first trap does not reach the boiling point of carbon dioxide in the impurity removal step or the transfer step is not performed for the first time, the carrier gas enters the first trap after passing through the first electrically controlled valve, the sixth port of the first valve assembly, the fifth port of the first valve assembly, and the second dryer. After the temperature of the first trap is increased, the target substance is converted into a gaseous state and discharged from the first trap along with the carrier gas. The target substance is then transferred to the second trap through the second port of the first valve assembly, the first port of the first valve assembly, the seventh port of the third valve assembly, the eighth port of the third valve assembly, the sixth port of the second valve assembly, and the fifth port of the second valve assembly. After the temperature of the second trap is reduced to liquefy the target substance, the remaining gas is discharged from the second trap through the second port of the second valve assembly and the first port of the second valve assembly. The injection step also includes controlling the action of the third valve assembly so that its first port is connected to its second port; the carrier gas enters the second capture trap after passing through the second electrically controlled valve, the first port of the second valve assembly, and the second port of the second valve assembly, carrying the target substance converted into gaseous state, and enters the chromatographic column after passing through the first port of the third valve assembly and the second port of the third valve assembly to obtain the separation result of the target substance.

9. The control method of the condensation pre-concentration equipment for trace organic gases according to claim 8, characterized in that: If the temperature of the first trap is raised to above the boiling point of carbon dioxide in the impurity removal step, and the transfer step is performed for the first time, the transfer step further includes controlling the action of the third valve assembly so that its sixth port is connected to its seventh port and its eighth port is connected to its ninth port; the carrier gas enters the first trap after passing through the first electrically controlled valve, the sixth port of the first valve assembly, the fifth port of the first valve assembly, and the second dryer; after the first trap is heated, the target substance is converted into gaseous state and discharged from the first trap along with the carrier gas, and then enters the carbon dioxide filter through the second port of the first valve assembly, the first port of the first valve assembly, the seventh port of the third valve assembly, and the sixth port of the third valve assembly to filter the carbon dioxide, and then transfers to the second trap through the sixth port of the second valve assembly and the fifth port of the second valve assembly; after the second trap is cooled to liquefy the target substance, the remaining gas is discharged from the second trap through the second port of the second valve assembly and the first port of the second valve assembly.

10. The control method for the condensation pre-concentration equipment for trace organic gases according to claim 9, characterized in that: The injection step is transformed into the following method: Control the second valve assembly so that its second port is connected to its third port, and its fourth port is connected to its fifth port; control the movement of the third valve assembly so that its first port is connected to its tenth port, and its second port is connected to its third port; control the second electrically controlled valve to open; the carrier gas enters the second trap after passing through the second electrically controlled valve, the third port of the second valve assembly, and the second port of the second valve assembly, and then carries the target substance that has become gaseous. After passing through the fifth port of the second valve assembly, the fourth port of the second valve assembly, the first port of the third valve assembly, and the tenth port of the third valve assembly, it passes through an additional chromatographic column to obtain additional separation results, and then passes through the third port of the third valve assembly and the second port of the third valve assembly to enter the chromatographic column to obtain the separation result of the target substance.

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