Device for increasing ice core sampling amount and use method thereof

Abstract

The invention belongs to the technical field of atmospheric monitoring equipment, and particularly relates to a device for increasing the ice nucleus sampling amount and a using method thereof. Comprising a virtual impactor, an air inlet pipe of the virtual impactor is communicated with a first diffusion drying pipe assembly, an air outlet of the virtual impactor is communicated with a growth chamber through a pipeline, and a bottom outlet of the growth chamber is sequentially communicated with an ice nucleus concentration measuring instrument, a first filter, a first flow quality controller, an air pump, a second diffusion drying pipe assembly, a second filter and a needle valve. A sheath gas input branch is communicated with a pipeline between the second filter and the needle valve, the sheath gas input branch is communicated with a side inlet of the growth chamber, a top overflow port of the growth chamber is respectively communicated with a vacuum pipeline and a nitrogen pipeline through a first three-way valve, and a third flow quality controller is communicated with the nitrogen pipeline. The concentration of particulate matters in the sample gas can be effectively increased, so that the lower limit of detection of the concentration of ice nuclei in the atmosphere is reduced, and the accuracy and reliability of measurement are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of atmospheric monitoring equipment, and particularly relates to a device for increasing the sampling amount of ice nuclei and a using method thereof. Background Art

[0002] Currently, commercially available ice nucleus concentration measurement instruments (such as CFDC), the biggest drawback of this instrument is that the sampling amount of ice nucleus aerosol samples is insufficient, that is, the sampling sample amount is on the small side, and sometimes it is lower than the detection limit of CFDC, resulting in the inability to detect the ice nucleus concentration in many regions. Therefore, it is urgent to design a device for increasing the sampling amount of ice nuclei and a using method thereof. Summary of the Invention

[0003] In view of the problems existing in the above-mentioned prior art, the present invention provides a device for increasing the sampling amount of ice nuclei and a using method thereof, and specifically discloses the following technical solutions:

[0004] A device for increasing the sampling amount of ice nuclei, comprising a virtual impactor, an intake pipe is connected to the intake port of the virtual impactor, a first diffusion drying tube assembly is communicated on the intake pipe, the outlet of the virtual impactor is communicated with the top inlet of a growth chamber through a pipeline, the bottom outlet of the growth chamber is communicated with an ice nucleus concentration measuring instrument, the outlet end of the ice nucleus concentration measuring instrument is successively communicated with a first filter, a first flow mass controller, an air pump, a second diffusion drying tube assembly, a second filter and a needle valve through pipelines, a sheath gas input branch is communicated on the pipeline between the second filter and the needle valve, the other end of the sheath gas input branch is communicated with the side inlet of the growth chamber, a second flow mass controller is communicated on the sheath gas input branch, the top overflow port of the growth chamber is respectively communicated with a vacuum pipeline and a nitrogen pipeline through a first three-way valve, and a third flow mass controller is communicated on the nitrogen pipeline.

[0005] Further, both the first diffusion drying tube assembly and the second diffusion drying tube assembly include two series-connected drying tubes, and silica gel and molecular sieve are respectively filled in the two drying tubes.

[0006] Further, a second three-way valve is communicated on the pipeline between the virtual impactor and the growth chamber, a sample gas branch is communicated on the pipeline between the virtual impactor and the second three-way valve, the other end of the sample gas branch is communicated with the other port of the second three-way valve, and a third filter is communicated on the sample gas branch.

[0007] Further, a pressure reducing valve, a pressure sensor and a check valve are communicated on the overflow pipeline between the first three-way valve and the top overflow port of the growth chamber.

[0008] A method for using a device for increasing the sampling amount of ice nuclei. First, the sample gas passes through the first diffusion drying tube assembly to remove moisture, then passes through a virtual impactor to remove larger particles in the sample gas, and then enters the growth chamber. The ice nuclei in the sample gas will condense into ice crystals, and then the sample gas carrying the ice crystals enters the ice nucleus concentration measuring instrument, which measures the ice nucleus concentration. After measurement, the sample gas flows through the first filter, the first flow mass controller, the air pump, the second diffusion drying tube assembly, and the second filter in sequence to remove moisture, particles, and droplets in the sample gas, and finally obtains sheath gas and transports it to the needle valve. The needle valve directly discharges a part of the sheath gas and re - inputs another part of the sheath gas into the growth chamber through the sheath gas input branch to isolate the sample gas from the side wall of the growth chamber and prevent ice nuclei from condensing into ice crystals on the side wall of the growth chamber.

[0009] Further, the flow rate of the sample gas flowing out of the growth chamber is the sum of the flow rate of the sample gas input into the growth chamber and the flow rate of the sheath gas.

[0010] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0011] In the present invention, by adding a virtual impactor, the particulate matter concentration in the sample gas can be effectively increased, the sampling amount can be increased, thereby reducing the detection lower limit of the ice nucleus concentration in the atmosphere and improving the accuracy and reliability of the measurement. Description of the Drawings

[0012] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0013] 1 - virtual impactor, 2 - first diffusion drying tube assembly, 3 - growth chamber, 4 - ice nucleus concentration measuring instrument, 5 - first filter, 6 - first flow mass controller, 7 - air pump, 8 - second diffusion drying tube assembly, 9 - second filter, 10 - needle valve, 11 - second flow mass controller, 12 - first three - way valve, 13 - vacuum pump, 14 - second three - way valve, 15 - third filter, 16 - pressure reducing valve, 17 - pressure sensor, 18 - check valve, 19 - third flow mass controller. Detailed Embodiments

[0014] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0015] Refer to Figure 1, A device for increasing the ice nucleus sampling volume, including a virtual impactor 1. The inlet of the virtual impactor 1 is connected to an inlet pipe, and a first diffusion drying tube assembly 2 is communicated with the inlet pipe. The first diffusion drying tube assembly 2 is used to remove moisture in the sample gas. The outlet of the virtual impactor 1 is communicated with the top inlet of the growth chamber 3 through a pipeline. The ice nuclei in the sample gas condense into ice crystals in the low-temperature environment of the growth chamber 3. The bottom outlet of the growth chamber 3 is communicated with an ice nucleus concentration measuring instrument 4, which is used to detect the ice crystal concentration (i.e., the ice nucleus concentration). The outlet end of the ice nucleus concentration measuring instrument 4 is successively communicated with a first filter 5, a first flow mass controller 6, an air pump 7, a second diffusion drying tube assembly 8, a second filter 9, and a needle valve 10 through pipelines, so as to remove particles and moisture in the sample gas and become sheath gas. A sheath gas input branch is communicated with the pipeline between the second filter 9 and the needle valve 10. The other end of the sheath gas input branch is communicated with the side inlet of the growth chamber 3. A second flow mass controller 11 is communicated with the sheath gas input branch, which is used to control the sheath gas input flow. The top overflow port of the growth chamber 3 is respectively communicated with a vacuum pipeline and a nitrogen pipeline through a first three-way valve 12. A third flow mass controller 19 is communicated with the nitrogen pipeline. The other end of the nitrogen pipeline is communicated with a nitrogen storage tank, and the other end of the vacuum pipeline is communicated with a vacuum pump 13.

[0016] In this embodiment, both the first diffusion drying tube assembly 2 and the second diffusion drying tube assembly 8 include two series-connected drying tubes, and silica gel and molecular sieve are respectively filled in the two drying tubes.

[0017] In this embodiment, a second three-way valve 14 is communicated with the pipeline between the virtual impactor 1 and the growth chamber 3. A sample gas branch is communicated with the pipeline between the virtual impactor 1 and the second three-way valve 14. The other end of the sample gas branch is communicated with another port of the second three-way valve 14. A third filter 15 is communicated with the sample gas branch. The sample gas can directly enter the virtual impactor 1 or enter the virtual impactor 1 after being filtered by the third filter 15.

[0018] In this embodiment, a pressure reducing valve 16, a pressure sensor 17, and a check valve 18 are communicated with the overflow pipeline between the first three-way valve 12 and the top overflow port of the growth chamber 3. The check valve 18 allows excessive nitrogen to flow out of the pipeline to prevent nitrogen from flowing back to other parts of the system; the pressure reducing valve 16 is used to prevent excessive pressurization of the chamber to ensure that the pressure in the growth chamber 3 does not exceed the safe operating range; the pressure sensor 17 is used to monitor the air pressure in the growth chamber 3 in real time.

[0019] A method for using a device for increasing the ice nucleus sampling amount. The sample gas first passes through the first diffusion drying tube assembly 2 to remove moisture, and then passes through the virtual impactor 1. The virtual impactor 1 is used to remove larger particles in the sample gas, and then enters the growth chamber 3. The ice nuclei in the sample gas will condense into ice crystals, and then the sample gas carrying the ice crystals enters the ice nucleus concentration measuring instrument 4. The ice nucleus concentration measuring instrument 4 measures the ice nucleus concentration. The sample gas after measurement flows through the first filter 5, the first flow mass controller 6, the air pump 7, the second diffusion drying tube assembly 8, and the second filter 9 in sequence, for removing moisture, particles, and droplets in the sample gas, and finally obtaining sheath gas to be delivered to the needle valve 10. The needle valve 10 directly discharges a part of the sheath gas, and re-enters another part of the sheath gas into the growth chamber 3 through the sheath gas input branch, for isolating the sample gas from the side wall of the growth chamber 3 to prevent ice nuclei from condensing into ice crystals on the side wall of the growth chamber 3.

[0020] In this embodiment, the flow rate of the sample gas flowing out of the growth chamber 3 is the sum of the flow rate of the sample gas input into the growth chamber 3 and the flow rate of the sheath gas.

[0021] The above are only preferred embodiments of the present invention, and do not impose any limitation on the technical scope of the present invention. Therefore, any minor modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. An apparatus for increasing the amount of ice nucleus sampling, characterized in that, It includes a virtual impactor, an intake pipe is connected to the air inlet of the virtual impactor, a first diffusion drying pipe assembly is communicated with the intake pipe, the air outlet of the virtual impactor is communicated with the top inlet of the growth chamber through a pipeline, the bottom outlet of the growth chamber is communicated with an ice nucleus concentration measuring instrument, the outlet end of the ice nucleus concentration measuring instrument is sequentially communicated with a first filter, a first flow mass controller, an air pump, a second diffusion drying pipe assembly, a second filter and a needle valve through pipelines, a sheath gas input branch is communicated with the pipeline between the second filter and the needle valve, the other end of the sheath gas input branch is communicated with the side inlet of the growth chamber, a second flow mass controller is communicated with the sheath gas input branch, the top overflow port of the growth chamber is respectively communicated with a vacuum pipeline and a nitrogen pipeline through a first three-way valve, and a third flow mass controller is communicated with the nitrogen pipeline.

2. The device for increasing the ice nucleus sampling amount according to claim 1, wherein, Both the first diffusion drying pipe assembly and the second diffusion drying pipe assembly include two series-connected drying pipes, and silica gel and molecular sieve are respectively filled in the two drying pipes.

3. The device for increasing the ice nucleus sampling amount according to claim 1, wherein A second three-way valve is communicated with the pipeline between the virtual impactor and the growth chamber, a sample gas branch is communicated with the pipeline between the virtual impactor and the second three-way valve, the other end of the sample gas branch is communicated with another port of the second three-way valve, and a third filter is communicated with the sample gas branch.

4. The device for increasing the ice nucleus sampling amount according to claim 1, characterized in that, A pressure reducing valve, a pressure sensor and a check valve are communicated with the overflow pipeline between the first three-way valve and the top overflow port of the growth chamber.

5. A method of using a device for increasing the amount of ice nucleus sampling according to any one of claims 1-4, characterized in that The sample gas first removes moisture through the first diffusion drying pipe assembly, then passes through the virtual impactor to remove larger particles in the sample gas by using the virtual impactor, and then enters the growth chamber. The ice nuclei in the sample gas will condense into ice crystals, and then the sample gas carries the ice crystals into the ice nucleus concentration measuring instrument. The ice nucleus concentration measuring instrument measures the ice nucleus concentration. The measured sample gas flows through the first filter, the first flow mass controller, the air pump, the second diffusion drying pipe assembly and the second filter in sequence to remove moisture, particles and droplets in the sample gas, and finally obtains sheath gas and transports it to the needle valve. The needle valve directly discharges a part of the sheath gas and re-injects another part of the sheath gas into the growth chamber through the sheath gas input branch to isolate the sample gas from the side wall of the growth chamber and prevent the ice nuclei from condensing into ice crystals on the side wall of the growth chamber.

6. The usage method of a device for increasing the ice nucleus sampling amount according to claim 5, characterized in that, The flow rate of the sample gas flowing out of the growth chamber is the sum of the flow rate of the sample gas input into the growth chamber and the flow rate of the sheath gas.

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