CN111999129A - Atmospheric water vapor collecting device and using method thereof - Google Patents

Abstract

The invention discloses an atmospheric water vapor collection device and a method for using the same. The device comprises a water vapor inlet cup, a liquid nitrogen storage box, a condensation box, a drying indicating box and a micro air pump. The water vapor inlet cup and the condensation box connection, the inside of the condensation box is provided with a cold trap device, the inside of the condensation box is located at the bottom of the cold trap device and a collection valve is installed, the condensation box and the liquid nitrogen storage tank are connected by a connecting pipe, and the liquid nitrogen storage box is connected The box is provided with a booster pump, a pressure gauge and a float gauge. The booster pump is connected to the pressure gauge. The float gauge is located inside the liquid nitrogen storage tank. The air outlet of the cold trap equipment is connected to the drying indicating box through the air outlet pipe. A drying indicator is arranged inside the drying indicating box, and the drying indicating box is connected with a micro air pump. The invention improves the automation of the atmospheric water vapor collection device, and the automatic addition of liquid nitrogen in the condensation chamber reduces the risk of low-temperature frostbite caused by artificially adding liquid nitrogen in the conventional traditional cold trap condensation method.

Description

A device for collecting atmospheric water vapor and method of using the same

technical field

The invention relates to the technical field of atmospheric water vapor sampling, in particular to an atmospheric water vapor collection device and a method for using the same.

Background technique

Atmospheric water vapor, hydrogen and oxygen stable isotopes are important indicators for revealing atmospheric circulation and hydrological cycle processes. The current lack of field monitoring data for atmospheric water vapor isotopes limits the promotion and application of atmospheric water vapor isotope research. The commonly used method is to use Rayleigh based on precipitation observations. Fractionation models make inference estimates of near-surface atmospheric water vapor isotopes, but this often depends on the amount of precipitation and the temperature that determines equilibrium fractionation. There are uncertainties, so the current derivation relationship is not accurate. This is mainly limited to the measured water vapor isotope data, and most studies still mainly rely on the calculation method of equilibrium fractionation, which virtually increases the uncertainty of quantitative studies such as regional water vapor recirculation and evapotranspiration segmentation of eco-hydrological processes. In addition, global and regional scale dynamic models are used to simulate isotope fractionation processes and content changes, but such models cannot be quantitatively analyzed at the scale of precipitation events. Therefore, to solve these problems, it is urgent to have a comprehensive and systematic direct observation and understanding of atmospheric water vapor isotopes.

The importance of on-site monitoring of atmospheric water vapor isotopes is unquestionable, but due to the limitations of monitoring methods, the actual monitoring data is very scarce for a long time. Although the appearance of spectroscopic observation instruments in recent years has circumvented this problem to a certain extent, such instruments are expensive and complicated to operate in the field, and it is difficult to ensure the stability of the instrument, which in turn affects the quality of water vapor isotopes. Therefore, in the field of eco-hydrology and hydrometeorology, it is necessary to collect atmospheric water vapor samples by traditional methods. At present, traditional methods of water vapor collection mainly include liquid nitrogen cold trap condensation, dry ice refrigeration method, desiccant dehydration method and Flask vacuum sampling bottle. , the problems of these methods mainly include: ① the traditional liquid nitrogen cold trap condensation requires continuous supply of liquid nitrogen to ensure that the cold trap is fully condensed and strictly control the gas flow rate; ② the dry ice refrigeration method is easy to cause isotope fractionation when the condensation temperature is not low enough, which is time-consuming laborious; ③ the hygroscopic desiccant contains O ₂ , which will cause isotope exchange; ④ the amount of water vapor collected by the vacuum sampling bottle method is small, which is not conducive to isotope analysis, especially in semi-arid regions.

Atmospheric water vapor isotope collection is an important link in isotopic ecohydrology research, which is directly related to the accurate assessment of regional precipitation processes and the calculation of water balance. Unscientific sampling methods will not only waste the funds and time of scientific and technological researchers, but also cause distortion of scientific research results. At present, the key problems to be solved in the collection of atmospheric water vapor based on the liquid nitrogen cold trap method are: (1) how to improve the utilization rate of liquid nitrogen during the collection process; (2) how to ensure the liquefaction rate of water vapor, thereby reducing the impact of water vapor isotope fractionation on the sample . Therefore, when using the liquid nitrogen cold trap method to collect atmospheric water vapor, the water vapor must be liquefied, collected, sealed and stored to prevent the influence of secondary evaporation on the isotope of water vapor samples, and at the same time improve the convenience and operability of the sampling device. Designed and selected to improve water vapor collection efficiency and improve isotope accuracy.

SUMMARY OF THE INVENTION

In order to overcome the problems existing in the related art, the embodiment of the present invention provides an atmospheric water vapor collection device and a method for using the same, which reduces the risk of low-temperature frostbite caused by artificially adding liquid nitrogen in the conventional cold trap condensation method, thereby improving the safety of the collection device. It improves the monitoring of water vapor flow, liquid nitrogen volume and temperature in the collection device.

An embodiment of the present invention provides an atmospheric water vapor collection device, including a water vapor inlet cup, a liquid nitrogen storage tank, a condensation box, a drying indicator box and a micro air pump. The water vapor inlet cup is connected to the condensation tank, and the condensation The inside of the box is provided with a cold trap device, the inside of the condensation box is located at the bottom of the cold trap device and a collection valve is installed, the condensation box and the liquid nitrogen storage tank are connected by a connecting pipe, and the liquid nitrogen storage box is provided with a booster valve. A pressure pump, a pressure gauge and a buoy gauge. The booster pump is connected to the pressure gauge. The buoy gauge is located inside the liquid nitrogen storage tank. The air outlet of the cold trap device is connected to the drying indicating box through the air outlet pipe. A drying indicator is arranged inside, and the drying indicator box is connected with a micro air pump.

Further, an air flow controller is provided at the connection between the water vapor inlet cup and the condensation box.

Further, the number of the cold trap devices is not less than two, and two adjacent cold trap devices are connected by conduits.

Further, a thermometer is provided inside the condensation box on the side of the cold trap device.

Further, the condensation box has a double-layer structure, the outer layer is an outer insulation layer made of PVC material, the inner layer is an inner cooling layer made of stainless steel, and a thermal insulation material is arranged between the outer insulation layer and the inner cooling layer.

A method of using an atmospheric water vapor collection device, comprising the following steps:

Install the water vapor inlet cup at the preset height H, and connect the airflow controller to the cold trap equipment in the condensation box through a conduit;

The liquid nitrogen storage box, the condensation box and the drying indicator box are connected in sequence;

Open the air flow controller and the air enters the condensate box from the water vapor inlet cup, and then start the cold trap equipment;

Under the action of the booster pump, an obvious pressure difference is formed between the liquid nitrogen storage tank and the condensing tank, and the liquid nitrogen is automatically added to the condensing tank;

After the condensation is over, take out the cold trap from the condensation box and place it at room temperature. After the condensed water is melted, mix the melted water from the cold trap into the sampling bottle, refrigerate at low temperature, and finally judge the atmospheric water vapor collection rate in the drying indicator box.

Further, the liquid nitrogen storage tank is also provided with a pressure gauge and a float ruler, the float ruler is used to judge the capacity of the liquid nitrogen in the storage room, and the pressure gauge is used to observe the pressure change of the liquid nitrogen storage tank.

Further, the cold trap is sealed and preserved during this process.

Further, a blue desiccant is arranged in the drying indicator box, and the desiccant is used to judge the collection effect of water vapor according to the color.

The technical solutions provided by the embodiments of the present invention have the following beneficial effects: the automation of the atmospheric water vapor collection device is improved, and the automatic addition of liquid nitrogen in the condensation chamber reduces the risk of low-temperature frostbite caused by artificially adding liquid nitrogen in the conventional traditional cold trap condensation method, which is more than traditional The low temperature method to collect water vapor saves liquid nitrogen, and the cold trap circulation system in the condensation chamber can effectively improve the water vapor condensation efficiency, effectively avoiding the water vapor isotope fractionation caused by the low water vapor collection rate.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention.

Description of drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description serve to explain the principles of the invention.

FIG. 1 is a schematic structural diagram of a device for collecting atmospheric water vapor in an embodiment of the present invention.

FIG. 2 is a schematic structural diagram of a condensation box in an atmospheric water vapor collection device in an embodiment of the present invention.

FIG. 3 is a flowchart of a method for using the atmospheric water vapor collection device in the embodiment of the present invention.

Detailed ways

Exemplary embodiments will be described in detail herein, examples of which are illustrated in the accompanying drawings. Where the following description refers to the drawings, the same numerals in different drawings refer to the same or similar elements unless otherwise indicated. The implementations described in the illustrative examples below are not intended to represent all implementations consistent with the present invention. Rather, they are merely examples of apparatus and related applications and methods consistent with some aspects of the invention as recited in the appended claims.

1 is a schematic structural diagram of an atmospheric water vapor collecting device in an embodiment of the present invention, and FIG. 2 is a structural schematic diagram of a condensation box in the atmospheric water vapor collecting device in an embodiment of the present invention. As shown in FIGS. 1 and 2 , the atmospheric water vapor collecting device, It includes a water vapor inlet cup 1, a liquid nitrogen storage box 8, a condensation box 9, a drying indicator box 10 and a micro air pump 12. The water vapor inlet cup is connected to the condensation box, and the connection between the water vapor inlet cup and the condensation box is provided. There is an air flow controller 2, and a cold trap device 6 is arranged inside the condensing box. The cold trap is made of low temperature resistant glass material. The cold trap device is easy to disassemble and carry. The amount of water vapor collected. There is a water outlet switch at the bottom of the cold trap, and a collection valve 601 is installed inside the condensation box at the bottom of the cold trap device. The number of cold trap devices is not less than two, between two adjacent cold trap devices. Through the connection of pipes, the loss of liquid nitrogen in the condensation chamber can be supplemented, and the condensation efficiency of atmospheric water vapor in the cold trap can be improved. A thermometer 7 is provided inside the side of the cold trap device.

The condensing box and the liquid nitrogen storage tank are connected by a connecting pipe. The condensing box is a double-layer structure, the outer layer is a PVC material and an outer insulation layer, and the inner layer is a stainless steel inner cooling layer. The thermal insulation material 901, the liquid nitrogen storage room can indicate the change of the liquid nitrogen capacity in the liquid nitrogen storage room through the float ruler, so as to ensure that the cold trap in the condensation chamber is completely submerged by the liquid nitrogen, and the water vapor circulates among the multiple cold traps, which effectively avoids The problem of incomplete condensation of water vapor that affects isotope fractionation ensures the test accuracy of isotopes in atmospheric water vapor samples. At the same time, the setting of the drying indicator chamber can facilitate the study and judgment of the collection efficiency of the entire device for atmospheric water vapor, which is conducive to checking the sealing of the device and liquid nitrogen storage. The box is provided with a booster pump 3, a pressure gauge 4 and a buoy gauge 5. The booster pump is connected to the pressure gauge. The buoy gauge is located inside the liquid nitrogen storage box. The air outlet of the cold trap equipment is connected to the drying indicating box through the air outlet pipe. A drying indicator 11 is arranged inside the drying indicating box, and the drying indicating box is connected with the micro air pump.

Fig. 3 is the flow chart of the using method of the atmospheric water vapor collecting device in the embodiment of the present invention, as shown in Fig. 3, the using method of this atmospheric water vapor collecting device, comprises the following steps:

Step 101: Install the water vapor inlet cup at a preset height H, and connect the airflow controller to the cold trap device in the condensation box through a conduit.

Step 102, the liquid nitrogen storage box, the condensation box and the drying indicating box are connected in sequence.

Step 103 , open the air flow controller and let the atmosphere enter the condensation box from the water vapor inlet cup, and then start the cold trap device.

Step 104: Under the action of the booster pump, a significant pressure difference is formed between the liquid nitrogen storage tank and the condensation tank, and the liquid nitrogen is automatically added to the condensation tank.

The liquid nitrogen storage tank is also provided with a pressure gauge and a float ruler, the float ruler is used to judge the capacity of the liquid nitrogen in the storage room, and the pressure gauge is used to observe the pressure change of the liquid nitrogen storage tank.

Step 105. After the condensation is completed, take out the cold trap from the condensation box and place it at room temperature. During this process, the cold trap is sealed and stored. After the condensed water is melted, the cold trap melted water is mixed into the sampling bottle, refrigerated at a low temperature, and finally The atmospheric water vapor collection rate is judged in the drying indicator box.

A blue desiccant is arranged in the drying indicator box, and the desiccant is used to judge the collection effect of water vapor according to the color.

By adopting the embodiments of the above invention, the automation of the atmospheric water vapor collection device is improved, and the automatic addition of liquid nitrogen in the condensation chamber reduces the risk of low-temperature frostbite caused by artificially adding liquid nitrogen in the conventional cold trap condensation method, and saves water vapor collection compared with the traditional low-temperature method. Liquid nitrogen can effectively improve the water vapor condensation efficiency through the cold trap circulation system in the condensation chamber, and effectively avoid the water vapor isotope fractionation caused by the low water vapor collection rate.

Other embodiments of the invention will readily suggest themselves to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses or adaptations of the invention which follow the general principles of the invention and which include common knowledge or conventional techniques in the art not disclosed by the invention .

It should be understood that the present invention is not limited to the precise structures described above and illustrated in the accompanying drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims (9)

1. The utility model provides an atmosphere steam collection device, its characterized in that, includes steam inlet cup, liquid nitrogen hutch, condensing box, dry indicator box and miniature air pump, the steam inlet cup is connected with the condensing box, the inside of condensing box is provided with cold trap equipment, the inside of condensing box is located the bottom of cold trap equipment and installs the collection valve, is connected through the connecting pipe between condensing box and the liquid nitrogen hutch, be provided with booster pump, manometer and float gauge on the liquid nitrogen hutch, the booster pump is connected with the manometer, and the float gauge is located the inside of liquid nitrogen hutch, and the gas outlet of cold trap equipment passes through the outlet duct and is connected with dry indicator box, dry indicator box's inside is provided with dry indicator, and dry indicator box is connected with miniature air pump.

2. The atmospheric water vapor collection device according to claim 1, wherein a gas flow controller is provided at a connection of the water vapor inlet cup and the condensation tank.

3. The atmospheric water vapor collection device according to claim 1, wherein the number of the cold trap devices is not less than two, and two adjacent cold trap devices are connected through a conduit.

4. The atmospheric water vapor collection device according to claim 1, wherein a thermometer is disposed inside the condensation tank on a side of the cold trap apparatus.

5. The atmospheric water vapor collection device according to claim 1, wherein the condensation tank has a double-layer structure, the outer layer is an outer PVC heat-insulating layer, the inner layer is an inner stainless steel cooling layer, and a heat-insulating material is arranged between the outer heat-insulating layer and the inner cooling layer.

6. The use method of the atmospheric water vapor collecting device is characterized by comprising the following steps:

installing a water vapor inlet cup at a preset height H, and connecting an air flow controller with cold trap equipment in a condenser box through a guide pipe;

the liquid nitrogen storage box, the condensing box and the drying indicating box are sequentially connected;

opening an air flow controller, enabling the atmosphere to enter a condensing box from a water vapor inlet cup, and starting cold trap equipment immediately;

under the action of the booster pump, an obvious pressure difference is formed between the liquid nitrogen storage box and the condenser box, and liquid nitrogen is automatically added into the condenser box;

and after condensation is finished, taking out the cold trap from the condensation box, placing the cold trap at normal temperature, mixing the cold trap melting water after the condensed water is melted, filling the cold trap melting water into a sampling bottle, refrigerating at low temperature, and finally studying and judging the atmospheric water vapor collection rate in a drying indicating box.

7. The use method of the atmospheric water vapor collection device according to claim 6, wherein a pressure gauge and a float gauge are further arranged in the liquid nitrogen storage tank, the float gauge is used for judging the volume of the liquid nitrogen in the storage tank, and the pressure gauge is used for observing the pressure change of the liquid nitrogen storage tank.

8. The method of using the atmospheric water vapor collection device according to claim 6, wherein said removing the cold trap from the condensation chamber is further performed at ambient temperature, during which the cold trap is hermetically sealed.

9. The use method of the atmospheric water vapor collection device according to claim 6, wherein a blue drying agent is arranged in the drying indication box, and the drying agent is used for judging the water vapor collection effect according to the color.

Images