CN115089993A - Gas pre-concentration equipment and control method - Google Patents
Gas pre-concentration equipment and control method Download PDFInfo
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- CN115089993A CN115089993A CN202210742085.5A CN202210742085A CN115089993A CN 115089993 A CN115089993 A CN 115089993A CN 202210742085 A CN202210742085 A CN 202210742085A CN 115089993 A CN115089993 A CN 115089993A
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- 238000000034 method Methods 0.000 title claims abstract description 29
- 239000007789 gas Substances 0.000 claims abstract description 118
- 239000000523 sample Substances 0.000 claims abstract description 79
- 238000010438 heat treatment Methods 0.000 claims abstract description 30
- 230000001276 controlling effect Effects 0.000 claims description 46
- 239000012159 carrier gas Substances 0.000 claims description 26
- 238000004458 analytical method Methods 0.000 claims description 22
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- 239000005431 greenhouse gas Substances 0.000 abstract description 8
- 238000012544 monitoring process Methods 0.000 abstract description 4
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 16
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D8/00—Cold traps; Cold baffles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D5/00—Condensation of vapours; Recovering volatile solvents by condensation
- B01D5/0033—Other features
- B01D5/0045—Vacuum condensation
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D5/00—Condensation of vapours; Recovering volatile solvents by condensation
- B01D5/0033—Other features
- B01D5/0051—Regulation processes; Control systems, e.g. valves
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- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Automation & Control Theory (AREA)
- Sampling And Sample Adjustment (AREA)
Abstract
The application discloses a gas preconcentration device and a control method, wherein the device comprises a sample introduction device, a first flow control device, a second flow control device, a heating control device, a refrigerating device, a trapping device, a passage adjusting device and a controller; the trapping device comprises a trapping trap, a thermocouple and a cold plate, wherein a temperature measuring probe of the thermocouple is arranged on the trapping trap, and the trapping trap is arranged on the cold plate; the passage adjusting device and the trapping trap are connected through a gas pipeline, and the trapping trap is connected with the heating control device through a lead; the first flow control device and the second flow control device are respectively connected with the passage adjusting device through gas pipelines; the cold end of the refrigerating device is connected with the cold plate, and the cold end of the refrigerating device and the collecting device are connected. The device in the scheme has the advantages of simple structure, high concentration efficiency and good repeatability, and can be used for online monitoring of various greenhouse gases.
Description
Technical Field
The invention relates to the technical field of gas analysis equipment, in particular to gas preconcentration equipment and a control method.
Background
With the increasing global warming, man-made greenhouse gas emissions have attracted a great deal of attention from international society. Is totally by a personThe content of greenhouse gases such as Hydrofluorocarbons (HFCs) and Perfluorocarbons (PFCs) in the ambient air is one part per trillion (10) -12 Ppt), the existing instrument cannot directly analyze due to the problem of detection limit, and the concentration of a target substance must be increased by adopting a pre-concentration mode. While greenhouse gases of both natural and man-made origin, such as carbon dioxide (CO) 2 ) Nitrous oxide (N) 2 O), etc., whose isotopic content needs to be analyzed in order to distinguish the contributions of natural and man-made sources. With carbon dioxide (CO) 2 ) For example, the conventional method for determining C-14 in air requires dissolving sufficient gas and alkaline solution, and then converting the solution into pure CO through the processes of precipitation, roasting and the like 2 And finally, measuring by using a liquid scintillation spectrometer. The defects are that the treatment process is complicated, the used instrument is expensive, and online monitoring cannot be realized. At present, portable technologies such as laser spectroscopy can be used for CO 2 、N 2 The method is characterized in that the O isotope is measured on line, but because the content of the isotope in the target gas is in the order of one thousandth of the isotope content, the pre-concentration of the target gas is still a necessary step.
Most of the preconcentration devices in the prior art are designed for Volatile Organic Compounds (VOC), semiconductor refrigeration is adopted to condense and concentrate target substances, but the refrigeration capacity of the semiconductor is limited (the minimum temperature is usually only-40 ℃), so that CO is difficult to condense 2 、N 2 O isothermal chamber gas is concentrated, and the prior art adopts multi-stage cold traps, the pre-concentration process is complex, and the repeatability is difficult to ensure
Disclosure of Invention
The technical problem to be solved by the application is that the existing gas preconcentration scheme has the problems of complex structure, incapability of ensuring repeatability and suitability for individual compounds, so that the application provides gas preconcentration equipment and a using method.
In view of the above technical problems, the present application provides the following technical solutions:
the embodiment of the application provides a gaseous pre-concentration equipment, includes:
the sample introduction device is used for accessing sample gas;
the first flow control device is used for accessing carrier gas and regulating the flow of the carrier gas;
the trapping device comprises a trapping trap, a thermocouple and a cold plate, wherein a temperature measuring probe of the thermocouple is arranged on the trapping trap, and the trapping trap is arranged on the cold plate;
a heating control device connected with the thermocouple and the trap in the trapping device;
a refrigeration device, the refrigeration end of which is connected to the cold plate in the trapping device;
the second flow control device is used for adjusting the flow of the gas input into the second flow control device;
a first interface of the passage adjusting device is connected with the analysis instrument, a second interface of the passage adjusting device is connected with one end of the trap, a third interface of the passage adjusting device is connected with an inlet of a second flow control device, a fourth interface of the passage adjusting device is connected with an outlet of the sample introduction device, a fifth interface of the passage adjusting device is connected with the other end of the trap, and a sixth interface of the passage adjusting device is connected with the first flow control device;
and the controller is used for controlling the on-off of the heating control device, the refrigeration device, the first flow control device and the second flow control device, controlling the set temperature value of the heating control device, controlling the set flow values of the first flow control device and the second flow control device and controlling the connection or disconnection of different interfaces of the passage regulating device so as to control the gas pre-concentration equipment to work in an enrichment mode, an analysis mode or a cleaning mode respectively.
In some embodiments, the passage regulating device includes a six-way multi-position valve, a first port of the six-way multi-position valve serves as the first port, a second port of the six-way multi-position valve serves as the second port, a third port of the six-way multi-position valve serves as the third port, a fourth port of the six-way multi-position valve serves as the fourth port, a fifth port of the six-way multi-position valve serves as the fifth port, and a sixth port of the six-way multi-position valve serves as the sixth port.
In some embodiments, the gas preconcentration apparatus provided in the above embodiments, the passage regulating device includes a four-way two-position valve and a six-way multi-position valve, a first interface of the four-way two-position valve is connected to a first interface of the six-way multi-position valve, and a third interface of the four-way two-position valve is connected to a sixth interface of the six-way multi-position valve;
a fourth port of the four-way two-position valve is used as the first port; a second interface of the six-way multi-position valve is used as the second interface; a third port of the six-way multi-position valve is used as the third port; a fourth port of the six-way multi-position valve is used as the fourth port; a fifth port of the six-way multi-position valve is used as the fifth port; and a second interface of the four-way two-position valve is used as the sixth interface.
In some embodiments, the trap includes a hollow cylindrical base, two straight pipe portions, and a coil portion connecting the two straight pipe portions, the coil portion is sleeved on an outer wall of the cylindrical base, and a temperature probe of the thermocouple is disposed on an inner wall of the cylindrical base.
In some embodiments, the gas pre-concentration apparatus further comprises:
and the water removing device is arranged between the sampling device and the fourth interface of the passage adjusting device.
In some embodiments, the gas preconcentration apparatus is provided, wherein the sample injection device includes a plurality of electromagnetic valves connected in parallel, inlets of different electromagnetic valves are respectively used for connecting a sample inlet or a standard gas inlet, and the controller controls a gas passage into the sample injection device by controlling opening and closing of different electromagnetic valves; or,
the sampling device comprises a multi-way sampling valve, different inlet ends of the multi-way sampling valve are respectively used for connecting a sample inlet or a standard gas inlet, and the controller controls a gas passage entering the sampling device by controlling a conducting branch of the multi-way sampling valve.
In some embodiments, the gas preconcentration apparatus further includes:
a filter disposed between the third port of the pathway adjustment device and the second flow control device.
In some embodiments, the gas preconcentration apparatus further includes:
the cold end of the refrigerating device and the trapping device are arranged in the vacuum cabin body;
the vacuum pump is connected with the vent hole of the vacuum chamber;
or,
the cold end of the refrigerating device and the trapping device are integrally coated inside the heat-insulating material.
An embodiment of the present application further provides a control method for a gas preconcentration apparatus, including the following steps:
an enrichment mode: controlling a refrigerating device and a heating control device to control the temperature of the trap at a first preset temperature, enabling the sample gas to pass through a sample introduction device, then enter the trap for enrichment through a passage adjusting device, and controlling the flow of the sample gas through a second flow control device;
desorption mode: firstly, controlling the connection or disconnection of different interfaces of the passage adjusting device to isolate the trap from an external gas pipeline, controlling the heating control device to raise the temperature of the trap to a second preset temperature, then controlling the connection or disconnection of the different interfaces of the passage adjusting device to connect the trap to the gas pipeline, introducing carrier gas into the trap through the first flow control device, and enabling the sample gas to enter an analysis instrument for detection after desorption;
purging mode: and controlling the first flow control device to introduce carrier gas into the trap to purge the trap, and controlling the heating control device to raise the temperature of the trap to a third preset temperature.
The control method described in some embodiments:
in the purging mode, the carrier gas enters the trap from the direction opposite to the enrichment mode by controlling the connection or disconnection of different interfaces of a channel adjusting device;
in the desorption mode, the method further comprises the impurity removal step: controlling different interfaces of the passage adjusting device to be communicated or disconnected so that the trap is connected to a gas pipeline, introducing carrier gas into the trap through the first flow control device, and controlling the refrigerating device and the heating control device to control the temperature of the trap to be a fourth preset temperature; the fourth preset temperature is between the first preset temperature and the second preset temperature.
Compared with the prior art, the technical scheme of the application has the following technical effects:
the gas preconcentration equipment comprises a sample introduction device, a first flow control device, a second flow control device, a heating control device, a refrigerating device, a trapping device, a passage adjusting device and a controller; the trapping device comprises a trapping trap, a thermocouple and a cold plate, wherein a temperature measuring probe of the thermocouple is arranged on the trapping trap, and the trapping trap is arranged on the cold plate; the passage adjusting device and the trapping trap are connected through a gas pipeline, and the trapping trap is connected with the heating control device through a lead; the first flow control device and the second flow control device are respectively connected with the passage adjusting device through gas pipelines; the cold end of the refrigerating device is connected with the cold plate, and the cold end of the refrigerating device and the trapping device are connected under a vacuum environment. The scheme can realize the enrichment and the analysis of various greenhouse gases by adopting a single trap, and has the advantages of simple structure, no need of using complex refrigeration modes such as liquid nitrogen and the like, low enrichment temperature, high enrichment efficiency, good repeatability and the like; can be used in combination with various analytical instruments, can be used for portable or on-line measuring instruments and can be used for on-line monitoring of various greenhouse gases.
Drawings
The objects and advantages of this application will be appreciated by the following detailed description of the preferred embodiments of the application, taken in conjunction with the accompanying drawings of which:
FIG. 1 is a schematic diagram of a gas preconcentration apparatus according to an embodiment of the present application;
FIG. 2 is a schematic structural diagram of a gas preconcentration apparatus according to another embodiment of the present application;
FIG. 3 is a schematic gas path diagram of the apparatus of FIG. 2 in an enrichment mode;
FIG. 4 is a schematic diagram of a gas path direction of the apparatus shown in FIG. 2 in an analysis mode;
FIG. 5 is a schematic diagram of a gas preconcentration apparatus according to yet another embodiment of the present application;
FIG. 6 is a schematic gas path diagram of the apparatus of FIG. 5 in an enrichment mode;
FIG. 7 is a schematic diagram of the gas path direction of the apparatus shown in FIG. 5 in the analysis mode;
FIG. 8 is a schematic gas path diagram of the apparatus of FIG. 5 in a purge mode.
Detailed Description
The technical solutions of the present application will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are only some embodiments of the present application, but not all embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments in the present application without making any creative effort belong to the protection scope of the present application.
In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present application, it should be noted that, unless otherwise explicitly stated or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, a fixed connection, a detachable connection, or an integral connection; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.
In addition, the technical features mentioned in the different embodiments of the present application described below may be combined with each other as long as they do not conflict with each other.
The present embodiment provides a gas preconcentration apparatus, as shown in fig. 1, which includes a sample introduction device 1, a first flow control device 3, a second flow control device 4, a heating control device 6, a refrigeration device 10, a trapping device, and a passage adjusting device 11. In some aspects, the first flow control device 3 and the second flow control device 4 are mass flow controllers. The refrigerating device 10 is a Stirling type refrigerating machine, helium is used as a refrigerating working medium, the Stirling refrigerating machine is driven by electric power, and compared with a traditional compressor refrigerating machine, the refrigerating device has the advantages of compact structure, low power consumption, stability and reliability, and does not need to use a refrigerant which can interfere with an analysis result.
As shown in the figure, the sample introduction device 1 is used for introducing a sample gas; the inlet of the sample introduction device 1 is connected with the sample inlet 12 through a pipeline 104, and the outlet of the sample introduction device is connected with the passage adjusting device 11 through a pipeline 106. The first flow control device 3 is used for receiving carrier gas and adjusting the flow of the carrier gas, a carrier gas inlet 13 is connected with an inlet of the first flow control device 3 through a pipeline 101, the carrier gas can be common carrier gas such as synthetic air, nitrogen or helium, and the like, and an outlet of the first flow control device 3 is connected with the passage adjusting device 11 through a pipeline 102; the trapping device comprises a trapping trap 7, a cold plate 8 and a thermocouple 5, wherein a temperature measuring probe of the thermocouple 5 is arranged on the trapping trap 7, and the trapping trap 7 is arranged on the cold plate 8; the trap 7 may be of the coil type. The temperature measuring probe of the thermocouple 5 is arranged on a coil of the trap 7, the other end of the thermocouple 5 is connected with the heating control device 6 through a lead 111, and the heating control device 6 is connected with the trap 7 through a lead. The refrigerating end of the refrigerating device 10 is connected with the cold plate 8 in the trapping device, as shown in the figure, in some schemes, the trapping trap 7 and the cold plate 8 are integrally wrapped by a heat insulation material 9, and the heat insulation material 9 can be a material resistant to low temperature of-100 ℃, such as epichlorohydrin rubber, epichlorohydrin rubber and chlorohydrin rubber. Set up insulation material 9 and can make refrigerating plant 10 and entrapment device isolated with external to avoid cooling process in refrigerating plant outer wall a large amount of steam that condenses, and then effectively guarantee to carry out accurate temperature control to entrapment trap 7. The second flow control device 4 is used for regulating the flow of the gas fed into the second flow control device 4, and the outlet of the second flow control device 4 is connected with the gas outlet 14 through a pipeline 110.
The first interface J1 of the passage adjusting device 11 is connected with the interface 15 of the analyzer through a pipeline 103, and the analyzer is used for detecting the output gas to be detected; a second interface J2 is connected with one end of the trap 7 through a pipeline 108, a third interface J3 is connected with an inlet of a second flow control device 4 through a pipeline 109, a fourth interface J4 is connected with a pipeline 106 so as to be connected with an outlet of the sample injection device 1, a fifth interface J5 is connected with the other end of the trap 7 through a pipeline 107, and a sixth interface J6 is connected with a pipeline 102 so as to be connected with the first flow control device 3; the controller controls the on/off of the first flow control device 3, the second flow control device 4, the heating control device 6 and the refrigerating device 10, controls the set temperature value of the heating control device 6, controls the set flow values of the first flow control device 3 and the second flow control device 4, and controls different interfaces of the passage regulating device 1 to be connected or disconnected so as to control the gas pre-concentration equipment to work in an enrichment mode, an analysis mode or a cleaning mode respectively. The set temperature value and the set flow value can be adjusted and set in a programming mode according to an actual scene.
The device in the scheme comprises a sample introduction device 1, a first flow control device 3, a second flow control device 4, a heating control device 6, a refrigerating device 10, a trapping device, a passage adjusting device 11 and a controller, and is simple in structure, high in concentration efficiency and good in repeatability, and can be used for online monitoring of various greenhouse gases.
As shown in the drawing, the second flow rate control device 4 may be provided upstream of the passage regulator 11 or downstream of the passage regulator 11. In the present embodiment, it is preferable to provide it downstream of the passage adjusting device 11, so that it is possible to prevent the test result from being disturbed by a trace amount of impurity gas generated by the components such as the sealing ring of the flow rate control device itself. In actual use, the second flow rate control device 4 may be installed upstream of the passage regulator 11 depending on the kind of the target gas and the characteristics of the flow rate control device.
In some embodiments, as shown in fig. 2 to 4, the passage adjusting device 11 includes a six-way multi-position valve 11A, as a preferred embodiment, the six-way multi-position valve 11A is a six-way twelve-position valve, the six-way twelve-position valve includes a valve body, a valve core, and a driver, the cross section of the valve body is circular, the valve body includes 6 pipeline interfaces, the pipeline interfaces are uniformly distributed on the same cross section of the valve body, the valve core is installed in the center of the valve body, the cross section is circular, a plurality of recessed flow passages are arranged along the circumference, intervals are provided between the flow passages, and when the controller controls the driver to drive the valve core to rotate, for any interface, communication with another adjacent interface through the flow passage can be achieved, or only communication with the flow passage is achieved, or communication with no flow passage is achieved. Therefore, the six-way multi-position valve 11A can achieve isolation of the two interfaces in addition to the function of the six-way two-position valve, and thus can be used for analyzing the trap 7 under the isolation condition. As shown in the figure, the first interface of the six-way multi-position valve 11A serves as the first interface, the second interface of the six-way multi-position valve 11A serves as the second interface, the third interface of the six-way multi-position valve 11A serves as the third interface, the fourth interface of the six-way multi-position valve 11A serves as the fourth interface, the fifth interface of the six-way multi-position valve 11A serves as the fifth interface, and the sixth interface of the six-way multi-position valve 11A serves as the sixth interface.
In other embodiments, as shown in fig. 5 to 8, the passage adjusting device 11 includes a four-way two-position valve 11B and a six-way multi-position valve 11A, an interface of the four-way two-position valve 11B is connected to an interface one of the six-way multi-position valve 11A via a pipeline 113, and an interface three of the four-way two-position valve 11B is connected to an interface six of the six-way multi-position valve 11A via a pipeline 114; a fourth interface of the four-way two-position valve 11B is used as the first interface and is connected with an interface 15 of an analysis instrument through a pipeline 115; a second port of the six-way multi-position valve 11A is used as the second port; a third port of the six-way multi-position valve 11A is used as the third port; a fourth port of the six-way multi-position valve 11A serves as the fourth port; a fifth port of the six-way multi-position valve 11A serves as the fifth port; and a second port of the four-way two-position valve 11B is used as the sixth port and is connected with the first flow control device 3 through a pipeline 112.
The above two passage adjusting devices 11 can realize the switching of the gas pre-concentration equipment in different working modes, and in the scheme shown in fig. 5, the gas flow direction of the carrier gas can be controlled to be switched when the cleaning mode is executed, so that the trap 7 can be more effectively purged through reverse air intake.
In the above embodiment, the trap 7 may be a straight pipe, a bent pipe, or a coil pipe, and is made of stainless steel, glass, or quartz. The trapping trap 7 is filled with an adsorbent and an adsorbent positioning device, and the positioning device is made of stainless steel or quartz. In some preferred schemes, as shown in fig. 5, the trap 7 includes a hollow cylindrical base 23, two straight pipe portions and a coil portion connecting the two straight pipe portions, the coil portion is sleeved on the outer wall of the cylindrical base 23, and the temperature probe of the thermocouple 5 is disposed on the inner wall of the cylindrical base 23. In this scheme, the one end of cylindrical base 23 contacts with cold dish 8, and the other end contacts with the coil pipe, and cylindrical base 23 plays the effect of buffering at the temperature rise and fall in-process, can improve temperature control's accuracy.
Preferably, the gas preconcentration device further comprises a vacuum chamber 24 instead of the thermal insulation material 9, the cold end of the refrigeration device 10 and the trapping device are disposed in a chamber body of the vacuum chamber 24, the vacuum chamber 24 is further provided with a vacuum pump 17, and the vacuum pump 17 is connected with the vent hole 18 of the vacuum chamber 24 through a pipeline 116 and a pipeline 117. The trapping device is arranged in the vacuum chamber 24 to achieve the effect of isolating the heat source. The body of the vacuum chamber 24 is typically made of metal, such as aluminum or stainless steel, and includes a base and an outer shell. The base and the shell are sealed through a sealing ring or a sealing gasket. The vacuum pump 17 provides vacuum to the vacuum chamber 24, and since the vacuum has excellent heat insulation characteristics, condensation of gas impurities on the surface of the trap 7 can be prevented, thereby achieving lower temperature and more accurate temperature control.
Further, as shown in the above figures, the gas preconcentration apparatus further includes a water removal device 2, and the water removal device 2 is disposed between the sample injection device 1 and the fourth interface of the passage adjusting device 11. Dewatering device 2 is the drying of Nafion pellicle, and Nafion pellicle drying tube has bilayer structure to the pellicle that can let the hydrone pass through separates. When the inner layer is filled with sample gas, the outer layer is filled with dry nitrogen or air reversely, and then the sample gas can be effectively dried. The Nafion semi-permeable membrane drying tube has the advantages of simple structure and small occupied space, and is particularly suitable for portable or movable equipment.
Preferably, as shown in fig. 5, the sample injection device 1 may include a plurality of electromagnetic valves connected in parallel, inlets of different electromagnetic valves are respectively used for connecting the sample inlet 12 or the standard gas inlet 19, and the controller controls opening and closing of different electromagnetic valves to control a gas passage into the sample injection device 1; or, the sample introduction device 1 includes a multi-way sample introduction valve (such as a ten-way sample introduction valve), different inlet ends of the multi-way sample introduction valve are respectively used for connecting the sample inlet 12 or the standard gas inlet 19, and the controller controls a gas passage entering the sample introduction device by controlling a conducting branch of the multi-way sample introduction valve. The sample introduction device 1 shown in the figure includes a first electromagnetic valve 20 and a second electromagnetic valve 21 connected in parallel as an example, wherein the first electromagnetic valve 20 is connected with a standard gas inlet 19 through a pipeline 118, the second electromagnetic valve 21 is connected with a sample inlet 12 through a pipeline 119, the number of the electromagnetic valves can be selected according to the actual situation, generally 2-16 electromagnetic valves connected in parallel are provided, and the pipeline 118 and the pipeline 119 can be implemented by copper pipes.
In some aspects, the gas pre-concentration apparatus may further include a filter 22 disposed between the third interface of the passage regulating device 11 and the second flow control device 4. The filter 22 can prevent particles in the gas from entering the second flow control device 4, thereby improving the accuracy of flow control and prolonging the service life of the device.
In some embodiments, there is also provided a method for controlling a gas preconcentration apparatus, in which the set temperature value of the heating control device includes a first preset temperature, a second preset temperature, a third preset temperature, and a fourth preset temperature, and the method may include:
performing an enrichment mode: controlling the refrigerating device and the heating control device to control the temperature of the trap at a first preset temperature, enabling the sample gas to pass through the sample introduction device, then enter the trap for enrichment through the passage adjusting device, and controlling the flow of the sample gas through the second flow control device;
the step of performing a desorption mode: firstly, controlling the connection or disconnection of different interfaces of the passage adjusting device to isolate the trap from an external gas pipeline, controlling the heating control device to raise the temperature of the trap to a second preset temperature, then controlling the connection or disconnection of the different interfaces of the passage adjusting device to connect the trap to the gas pipeline, introducing carrier gas into the trap through the first flow control device, and enabling the sample gas to enter an analysis instrument for detection after desorption;
a step of executing a purge mode: and controlling the first flow control device to introduce carrier gas into the trap to purge the trap, and controlling the heating control device to raise the temperature of the trap to a third preset temperature.
For the device structure shown in fig. 2, the execution process of the above different modes includes:
(1.1): in the enrichment mode, as shown in fig. 3, the cold head of the refrigeration device 10 delivers the low temperature to the cold plate 8, lowering the temperature of the trap 7 to a first preset temperature. After passing through the sample introduction device 1, the sample gas enters a six-way multi-position valve 11A through a water removal device 2. The controller controls the six-way multi-position valve 11A to enable a port four to be communicated with a port five, a port two to be communicated with a port three, and a port one to be communicated with a port six. The sample gas enters from the interface four of the six-way multi-position valve 11A, and flows out from the interface five of the six-way multi-position valve 11A to enter the trap 7. And target gas components are enriched in the trap 7, and residual gas returns to a second interface of the six-way multi-position valve 11A, flows out of a third interface of the six-way multi-position valve 11A, is controlled by the second flow control device 4, and is discharged from a gas outlet 14. In the above scheme, during the enrichment process, the carrier gas can be introduced into the interface 15 of the analyzer through the first flow control device 3 to purge the pipeline and the analyzer.
In general, the first preset temperature and the flow rate of the second flow control device 4 need to be determined according to the boiling point and polarity of the target gas component, the concentration thereof in the sample gas, and the detection requirements of the analysis instrument. In this embodiment, the first preset temperature is set to-100 ℃, and CO can be treated 2 、N 2 O, CFCs, etc., in the presence of a gas component of interest. The first preset temperature is set to-160 ℃, so that the CF can be realized 4 And target components such as PFCs, HFCs and the like are effectively enriched. The flow rate of the second flow control device 4 can be set to be 100-500 ml/min, and the larger the flow rate is, the longer the enrichment time is, and the higher the pre-concentration ratio is.
(1.2) desorption mode: first, the trap 7 is isolated from the external gas line by controlling the six-way multi-position valve 11A, as shown in fig. 2. The temperature of the trap 7 is raised to a second preset temperature by the heating control device 6, so that the target gas component enriched in the trap 7 is desorbed and released into the internal pipeline of the trap 7. And then, controlling the six-way multi-position valve 11A to enable the first interface to be communicated with the second interface, the third interface to be communicated with the fourth interface and the fifth interface to be communicated with the sixth interface, introducing carrier gas into the trap 7 through the first flow control device 3, and sending the desorbed target gas component into an analysis instrument for detection through the first interface of the six-way multi-position valve 11A as shown in fig. 4.
In general, the second preset temperature, the carrier gas flow and the sample injection time are required to be determined according to the boiling points and polarities of the target component and the impurity gas, and the requirements of a downstream analysis instrument. In the present embodiment, N is referred to 2 When the O is pre-concentrated, the second preset temperature, the carrier flow and the sample injection time are respectively set to be-30 ℃, 50 ml/min and 2 min. Such as the flow setting of the second flow control means 4 in the enrichment stageSetting the concentration at 500 ml/min, setting the enrichment time at 20 min, then the sample volume is 10L, and the preconcentration ratio is 100:1, thus the concentration of the target gas component can be increased to 100 times of the sample gas.
(1.3) purge mode: the purge process is used to completely remove the impurities remaining in the trap 7, and to restore the trap 7 to the enrichment-ready state. The line state of the pre-concentration device in the purging process is shown in fig. 4, and is the same as the sample injection stage in the desorption step, except that the temperature of the trap 7 is further increased to a third preset temperature. In this example, the carrier gas purge flow is maintained at 50 ml/min and the third preset temperature is 100 ℃. The higher third preset temperature is helpful to thoroughly remove the residual impurities in the trap 7, and the repeatability of the system is improved.
Further, the time of the purge process may be determined according to the characteristics of the trap 7, and is 5 min in the present embodiment. After the purging process is finished, the temperature of the trap 7 is reduced to a first preset temperature, the six-way multi-position valve 11 is switched back to the key state of the enrichment step, and the next sample is ready to be pre-concentrated.
According to the apparatus and control method provided in the above scheme, about 30 minutes are required to complete the pre-concentration process of one sample, and only 20 minutes are required if the pre-concentration ratio is reduced to 50: 1. Therefore, the pre-concentration equipment can be used for high-frequency online analysis or on-site rapid detection of the environmental gas.
In the above control method, in addition to the above steps, an additional purge step may be included between the execution steps of the enrichment mode and the desorption mode. The apparatus line state is the same as that of fig. 4 at this step, but the trap 7 is heated to a fourth predetermined temperature. The temperature value is between the first preset temperature and the second preset temperature, and can be used for removing the interference of certain impurities and avoiding the interference of the impurities on qualitative and quantitative analysis results when the impurities enter an analysis instrument through direct thermal desorption after enrichment.
For the device structure shown in fig. 5, the execution process of the above different modes includes:
(2.1) enrichment mode: as shown in fig. 6, the cold head of the refrigeration apparatus 10 transfers the low temperature to the cold plate 8, and the temperature of the trap 7 is lowered to the first preset temperature. The second electromagnetic valve 21 in the sample injection device 1 is opened, and the sample gas enters the six-way multi-position valve 11A through the water removal device 2. The controller controls the six-way multi-position valve 11A to be communicated with the port five, the port two to be communicated with the port three and the port one to be communicated with the port six. The sample gas enters from the interface four, and the sample gas flows out from the interface five and enters the trap 7. And target gas components are enriched in the trap 7, and the residual gas returns to the second interface of the six-way multi-position valve 11A, flows out from the third interface, is controlled by the second flow control device 4, and is discharged from the gas outlet 14.
(2.2) desorption mode: first, the trap 7 is isolated from the external gas line by controlling the six-way multi-position valve 11A, as shown in fig. 5. The temperature of the trap 7 is raised to a second preset temperature by the heating control device 6, so that the target gas component enriched in the trap 7 is desorbed and released into the internal pipeline of the trap 7. Then, the six-way multi-position valve 11 is controlled to enable the first interface to be communicated with the second interface, the third interface to be communicated with the fourth interface, and the fifth interface to be communicated with the sixth interface, the four-way two-position valve 11B is controlled to enable the first interface to be communicated with the fourth interface and the second interface to be communicated with the third interface, carrier gas is introduced into the trapping trap 7 through the first flow control device 3, as shown in fig. 7, the desorbed target gas component is sent to the first interface of the four-way two-position valve 11B through the first interface, and then is sent to an analysis instrument through a pipeline 115 through the fourth interface to be detected.
(2.3) purge mode: and controlling the four-way two-position valve 11B to enable the first port to be communicated with the second port and the third port to be communicated with the fourth port, as shown in figure 8. At the moment, the carrier gas enters the trap from the direction opposite to that in the enrichment step for purging, which is helpful for thoroughly removing the residual impurities, so that the enrichment efficiency and the repeatability of the pre-concentration of the equipment can be further improved, and the analysis precision is improved.
In the above scheme, the first preset temperature is below-100 ℃, the second preset temperature is above-60 ℃, and the third preset temperature is above 80 ℃. The first preset temperature is used for sample enrichment, and the lower first preset temperature can trap low-boiling-point greenhouse gases as completely as possible, so that the trapping efficiency is improved. The second predetermined temperature is used for sample resolution and is typically above the boiling point of the target gas. The third preset temperature is used for purging the trap, and the higher temperature is beneficial to completely removing residual components in the trap. Meanwhile, the gas pre-concentration device in the scheme can be used for analyzing off-line sampling samples and can also be used for on-line analysis. When a plurality of offline sampling samples need to be analyzed, the samples can be automatically switched through 2-16 parallel electromagnetic valves or 1 multi-position sample injection valve. When on-line analysis is carried out, the sample and the standard gas can be switched by 2 electromagnetic valves connected in parallel.
It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. This need not be, nor should it be exhaustive of all embodiments. And obvious variations or modifications from the teachings herein remain within the scope of this application.
Claims (10)
1. A gas preconcentration apparatus, comprising:
the sample introduction device is used for accessing sample gas;
the first flow control device is used for accessing carrier gas and regulating the flow of the carrier gas;
the trapping device comprises a trapping trap, a thermocouple and a cold plate, wherein a temperature measuring probe of the thermocouple is arranged on the trapping trap, and the trapping trap is arranged on the cold plate;
a heating control device connected to the thermocouple and the trap in the trap device;
a refrigeration device, the refrigeration end of which is connected to the cold plate in the trapping device;
the second flow control device is used for adjusting the flow of the gas input into the second flow control device;
a first interface of the passage adjusting device is connected with the analysis instrument, a second interface of the passage adjusting device is connected with one end of the trap, a third interface of the passage adjusting device is connected with an inlet of a second flow control device, a fourth interface of the passage adjusting device is connected with an outlet of the sample introduction device, a fifth interface of the passage adjusting device is connected with the other end of the trap, and a sixth interface of the passage adjusting device is connected with the first flow control device;
and the controller is used for controlling the heating control device, the refrigerating device, the first flow control device and the second flow control device to be opened and closed, controlling the set temperature value of the heating control device, controlling the set flow values of the first flow control device and the second flow control device and controlling different interfaces of the passage regulating device to be connected or disconnected so as to control the gas pre-concentration equipment to work in an enrichment mode, an analysis mode or a cleaning mode respectively.
2. The gas preconcentration device according to claim 1, wherein:
the passage adjusting device comprises a six-way multi-position valve, a first interface of the six-way multi-position valve serves as the first interface, a second interface of the six-way multi-position valve serves as the second interface, a third interface of the six-way multi-position valve serves as the third interface, a fourth interface of the six-way multi-position valve serves as the fourth interface, a fifth interface of the six-way multi-position valve serves as the fifth interface, and a sixth interface of the six-way multi-position valve serves as the sixth interface.
3. The gas preconcentration device according to claim 1, wherein:
the passage adjusting device comprises a four-way two-position valve and a six-way multi-position valve, wherein a first interface of the four-way two-position valve is connected with a first interface of the six-way multi-position valve, and a third interface of the four-way two-position valve is connected with a sixth interface of the six-way multi-position valve;
a fourth port of the four-way two-position valve is used as the first port; a second interface of the six-way multi-position valve is used as the second interface; a third port of the six-way multi-position valve is used as the third port; a fourth port of the six-way multi-position valve is used as the fourth port; a fifth port of the six-way multi-position valve is used as the fifth port; and a second interface of the four-way two-position valve is used as the sixth interface.
4. A gas preconcentration device according to any one of claims 1 to 3, wherein:
the trapping trap comprises a hollow cylindrical base, two straight pipe parts and a coil pipe part connected with the two straight pipe parts, the coil pipe part is sleeved on the outer wall of the cylindrical base, and a temperature probe of the thermocouple is arranged on the inner wall of the cylindrical base.
5. The gas preconcentration device according to claim 4, further comprising:
and the water removing device is arranged between the sampling device and the fourth interface of the passage adjusting device.
6. The gas preconcentration device according to claim 5, wherein:
the sample introduction device comprises a plurality of electromagnetic valves connected in parallel, inlets of different electromagnetic valves are respectively used for connecting a sample inlet or a standard gas inlet, and the controller controls a gas passage entering the sample introduction device by controlling the opening and closing of different electromagnetic valves; or,
the sampling device comprises a multi-way sampling valve, different inlet ends of the multi-way sampling valve are respectively used for connecting a sample inlet or a standard gas inlet, and the controller controls a gas passage entering the sampling device by controlling a conducting branch of the multi-way sampling valve.
7. The gas preconcentration device according to claim 4, further comprising:
a filter disposed between the third port of the pathway adjustment device and the second flow control device.
8. The gas preconcentration device according to claim 4, further comprising:
the cold end of the refrigerating device and the trapping device are arranged in the vacuum cabin body;
the vacuum pump is connected with the vent hole of the vacuum chamber;
or,
the cold end of the refrigerating device and the trapping device are integrally coated inside the heat-insulating material.
9. A method for controlling a gas preconcentration apparatus according to any one of claims 1 to 8, comprising the steps of:
the step of performing the enrichment mode: controlling a refrigerating device and a heating control device to control the temperature of the trap at a first preset temperature, enabling the sample gas to pass through a sample introduction device, then enter the trap for enrichment through a passage adjusting device, and controlling the flow of the sample gas through a second flow control device;
a step of performing a desorption mode: firstly, controlling the connection or disconnection of different interfaces of the passage adjusting device to isolate the trap from an external gas pipeline, controlling the heating control device to raise the temperature of the trap to a second preset temperature, then controlling the connection or disconnection of the different interfaces of the passage adjusting device to connect the trap to the gas pipeline, introducing carrier gas into the trap through the first flow control device, and enabling the sample gas to enter an analysis instrument for detection after desorption;
a step of executing a purge mode: and controlling the first flow control device to introduce carrier gas into the trap to purge the trap, and controlling the heating control device to raise the temperature of the trap to a third preset temperature.
10. The control method according to claim 9, characterized in that:
in the purging mode, the carrier gas enters the trap from the direction opposite to the enrichment mode by controlling the connection or disconnection of different interfaces of a channel adjusting device;
in the desorption mode, the method further comprises the impurity removal step: controlling different interfaces of the passage adjusting device to be communicated or disconnected so that the trap is connected to a gas pipeline, introducing carrier gas into the trap through the first flow control device, and controlling the refrigerating device and the heating control device to control the temperature of the trap to be a fourth preset temperature; the fourth preset temperature is between the first preset temperature and the second preset temperature.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115718029A (en) * | 2022-11-16 | 2023-02-28 | 泰通科技（广州）有限公司 | Three-stage refrigeration atmosphere preconcentrator and temperature control method thereof |
| CN115856176A (en) * | 2023-02-06 | 2023-03-28 | 北京鹏宇昌亚环保科技有限公司 | VOCs pre-concentration processing assembly and processing method in environment monitoring instrument |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20040151622A1 (en) * | 2002-12-31 | 2004-08-05 | Chun-Mao Tseng | Ultra-trace automatic mercury species analyzer |
| CN207996449U (en) * | 2017-12-12 | 2018-10-23 | 优泰科技（深圳）有限公司 | A kind of cold-trap |
| CN109865309A (en) * | 2017-12-01 | 2019-06-11 | 中国科学院大连化学物理研究所 | A kind of enrichment of volatile organic trace compounds low temperature and Thermal desorption integration cold-trap |
| US20200400622A1 (en) * | 2019-06-24 | 2020-12-24 | Peking University | Online measuring system, method and application for semi-volatile organic compound in gas phase |
| CN218188003U (en) * | 2022-06-28 | 2023-01-03 | 华纳创新(苏州)先进制造有限公司 | Gas pre-concentration equipment |
-
2022
- 2022-06-28 CN CN202210742085.5A patent/CN115089993A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20040151622A1 (en) * | 2002-12-31 | 2004-08-05 | Chun-Mao Tseng | Ultra-trace automatic mercury species analyzer |
| CN109865309A (en) * | 2017-12-01 | 2019-06-11 | 中国科学院大连化学物理研究所 | A kind of enrichment of volatile organic trace compounds low temperature and Thermal desorption integration cold-trap |
| CN207996449U (en) * | 2017-12-12 | 2018-10-23 | 优泰科技（深圳）有限公司 | A kind of cold-trap |
| US20200400622A1 (en) * | 2019-06-24 | 2020-12-24 | Peking University | Online measuring system, method and application for semi-volatile organic compound in gas phase |
| CN218188003U (en) * | 2022-06-28 | 2023-01-03 | 华纳创新(苏州)先进制造有限公司 | Gas pre-concentration equipment |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115718029A (en) * | 2022-11-16 | 2023-02-28 | 泰通科技（广州）有限公司 | Three-stage refrigeration atmosphere preconcentrator and temperature control method thereof |
| CN115856176A (en) * | 2023-02-06 | 2023-03-28 | 北京鹏宇昌亚环保科技有限公司 | VOCs pre-concentration processing assembly and processing method in environment monitoring instrument |
| CN115856176B (en) * | 2023-02-06 | 2023-08-08 | 北京鹏宇昌亚环保科技有限公司 | VOCs pre-concentration processing assembly and processing method in environment monitoring instrument |
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