Portable in-situ measurement device and method for bubble flux of mud-water interface used in multiple scenes

Abstract

The invention discloses a portable multi-scene mud-water interface bubbling flux in-situ measurement device and method, and relates to the technical field of sampling, the measurement device comprises a mud-water interface gas collection assembly, a gas sample storage assembly and a pure medium filling assembly, the mud-water interface gas collecting assembly is fixedly connected with one end of the pure medium filling assembly, the gas sample storage assembly is fixedly connected with the mud-water interface gas collecting assembly, the pure medium filling assembly is connected with an external pure medium containing container, and the mud-water interface gas collecting assembly is responsible for being inserted into sediment. The gas sample storage assembly 2 exhausts original gas in the measuring device, so that the measuring device is filled with water columns, the pure medium filling assembly replaces the water body in the measuring device according to the ratio of 1: 2, and the gas sample storage assembly replaces the replaced water body with collected mud-water interface gas according to the ratio of 1: 1; the collection and extraction of the mud-water interface gas are realized.

Description

Technical Field

[0001] The present invention relates to the field of sampling technology, and in particular to a convenient in-situ measurement device and method for bubbling flux at a mud-water interface for use in multiple scenarios. Background Art

[0002] In aquatic ecosystems, the mud-water interface is a key area for studying biogeochemical processes between water bodies and bottom mud sediments, especially in terms of gas release and absorption exchange. At the same time, the mud-water interface is also the main place where biogeochemical processes occur. The biophysical and chemical reactions occurring in the interface, as well as the process of decomposition of organic matter in sediments involving metabolic activities, will release a variety of gases. This is an important manifestation of the coupling of geochemical cycles and biological systems in the water environment, and is an important way to control and regulate the transport and exchange of substances between water bodies and sediments. Therefore, the study of gas exchange fluxes at the mud-water interface is an important research topic in the current field of environmental science. These gas exchange studies are of great significance to the energy balance and climate change of environmental systems, and traditional gas collection and sampling methods have certain limitations. Therefore, the development of new technologies has enabled researchers to monitor gas exchange at the mud-water interface more accurately and intuitively, providing reliable research data for scientific research, revealing the mechanism of interaction between bottom mud and water bodies, and providing a scientific basis for environmental management and pollution control.

[0003] At present, there are relatively few technologies for collecting gas at the mud-water interface. It is understood that there are two methods: the early mud-water interface inverted funnel gas collection method and the static gas phase collection method. Among them, the early mud-water interface inverted funnel gas collection method collects gas at the mud-water interface by immersing its bottom in the sediment. However, most of the early inverted funnel technologies were large in size, complex in operation, and poor in controllability. The collection progress was unclear and the interface was severely disturbed, causing the collected gas to remain in the in-situ water environment for a long time, facing the possibility of gas sample contamination or chemical reaction consumption, and it has not been put into large-scale field use. The existing static gas phase collection method is to set a sampling bottle or sampling channel at the bottom of the water body to collect gas on the surface of the sediment. It can be suitable for long-term monitoring, but its limitation is that it cannot provide gas release information with high temporal and spatial resolution, especially in a dynamic environment. It cannot meet the needs of rapid and accurate collection of gas exchanged at the mud-water interface, and the actual operation is poor. Summary of the invention

[0004] The purpose of the present invention is to provide a convenient multi-scenario mud-water interface bubble flux in-situ measurement device and method to solve the problems raised in the prior art.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] The measuring device includes a mud-water interface gas collection component, a gas sample storage component and a pure medium filling component. The mud-water interface gas collection component and one end of the pure medium filling component are fixedly connected, the gas sample storage component and the mud-water interface gas collection component are fixedly connected, the pure medium filling component passes through the gas sample storage component, and part of the pure medium filling component and the gas sample storage component are fixedly connected.

[0007] The mud-water interface gas collection component is responsible for inserting into the sediment to reduce the interface disturbance intensity caused by water flow movement and further collect the mud-water interface gas. The gas sample storage component first discharges the original gas inside the measuring device to fill the water column inside the measuring device. The pure medium filling component replaces the water body inside the measuring device in a 1:2 ratio to fill the water column inside the measuring device. The gas sample storage component then replaces the water body in the filled water column with the collected mud-water interface gas in a 1:1 ratio to achieve the collection and extraction of mud-water interface gas.

[0008] Furthermore, the mud-water interface gas collection assembly includes a stabilizing frame, a temperature probe, a pull ring, a gas collecting hood, an air guide pipe, a gas collecting one-way valve and a three-way pipe. The stabilizing frame is divided into an upper frame and a lower frame. The upper end surface of the lower frame is provided with a threaded hole and a positioning column. The upper frame is provided with a threaded through hole at a position corresponding to the threaded hole of the lower frame. The pull ring is threadedly connected to the upper frame, and the pull ring passes through the threaded through hole of the upper frame and is threadedly connected to the lower frame. A positioning hole is provided at the bottom end of the gas collecting hood, and the positioning column passes through the positioning hole of the gas collecting hood. The bottom end portion of the gas collecting hood is located between the upper frame and the lower frame. The gas collecting hood and the positioning column are slidably connected between the frames, the temperature probe and the upper end surface of the bottom end of the gas collecting hood are fixedly connected, the temperature probe and the gas sample storage assembly are electrically connected, the gas collection one-way valve and the exhaust port at the upper end of the gas collecting hood are sealed and connected, a straight-through interface of the three-way pipe is fixedly connected to the gas collection one-way valve, another straight-through interface of the three-way pipe is fixedly connected to one end of the air guide tube, the corner interface of the three-way pipe is fixedly connected to the pure medium filling assembly, and the other interface of the air guide tube is fixedly connected to the gas sample storage assembly.

[0009] First, install the gas collecting hood and the stabilizing frame, and then adjust the height of the gas collecting hood inside the stabilizing frame according to actual needs to realize in-situ observation of the mud-water interface of various aquatic ecosystems in the field environment. The mud-water interface gas flows upward from the bottom of the gas collecting hood through the gas outlet on the top of the gas collecting hood. Since the gas collection one-way valve is connected to the gas outlet on the top of the gas collecting hood, the mud-water interface gas can only pass from the gas outlet on the top of the gas collecting hood to the three-way pipe, and the three-way pipe then transports the mud-water interface gas to the gas guide pipe, and finally to the gas sample storage assembly.

[0010] Furthermore, the gas sample storage component includes a gas collecting bottle, a collecting bottle air inlet, a collecting bottle exhaust port, a collecting bottle fixing frame, a storage micro vacuum pump, a rubber air cushion, an exhaust pipe, a first three-way valve, a circular platform bottom plate, a collecting bottle drain port, a timer and a thermometer module, a manual pressure reducing pipe, a storage one-way valve and a second three-way valve, the circular platform bottom plate and the rubber air cushion are fixedly connected, the circular platform bottom plate is located in the inner ring of the rubber air cushion, the timer and the thermometer module are fixedly connected to the upper end surface of the circular platform bottom plate, the timer and the thermometer module are electrically connected to the temperature probe, part of the pure medium filling component is fixedly connected to the upper end surface of the circular platform bottom plate, the collecting bottle fixing frame is fixedly connected to the upper end surface of the circular platform bottom plate, the collecting bottle The central axis of the fixing frame coincides with the central axis of the bottom plate of the circular platform, the upper end of the collecting bottle fixing frame is a circular ring, the gas collecting bottle is placed in the circular ring at the upper end of the collecting bottle fixing frame, the air inlet of the collecting bottle is fixedly connected to the air guide tube, the water outlet of the collecting bottle is fixedly connected to the inlet of the storage one-way valve, a straight-through interface of the first three-way valve is fixedly connected to the outlet of the storage one-way valve, the corner interface of the first three-way valve is fixedly connected to the manual pressure reducing tube, the exhaust port of the collecting bottle is fixedly connected to a straight-through interface of the second three-way valve, the other straight-through interface of the second three-way valve is a sample gas transfer interface, the corner interface of the second three-way valve is fixedly connected to one end of the exhaust pipe, and the other end of the exhaust pipe is fixedly connected to the water inlet of the storage micro vacuum pump.

[0011] After completing the installation and placement of the mud-water interface gas collection component, connect the second three-way valve to the exhaust port of the collection bottle, start the storage micro vacuum pump to evacuate the residual gas inside the measuring device until the measuring device is completely filled with water column. After completion, close the second three-way valve, then adjust the first three-way valve to connect the collection bottle drain port and the manual decompression pipe, use injection gas for manual decompression, observe that there are no residual bubbles in the gas collection bottle, adjust the first three-way valve to connect the two straight-through interfaces to achieve automatic drainage, then start the pure medium filling component, replace the water volume of the upper device of the gas collection hood, and the water in the replaced gas collection bottle is discharged through the collection bottle drain port according to Volume ratio: displacement discharge, so that the interior of the upper device of the gas collecting hood of the measuring device is filled with pure medium, and finally the pure medium filling component is closed, the first three-way valve remains unchanged, because the measuring device is sealed as a whole, and the collection bottle drain port is one-way due to the storage check valve, the water in the gas collection bottle will not flow back and fall due to gravitational potential energy, but as the gas at the mud-water interface is gradually collected by the gas collecting hood and aggregated at the top of the gas collecting hood, it is affected by the water pressure at the mud-water interface. At this time, the gas pressure at the top of the gas collecting hood will be greater than the sum of the valve pressure at the drain port of the collection bottle and the atmospheric pressure, so that the gas will enter the gas collection bottle through the air duct, so as to collect and extract the gas released from the mud-water interface.

[0012] Furthermore, the pure medium filling component includes a pure medium one-way valve, a pure medium conduit, a pure medium micro vacuum pump and a pure medium input pipe, one end of the pure medium conduit is fixedly connected to the corner interface of the three-way pipe, the other end of the pure medium conduit is fixedly connected to the outlet of the pure medium micro vacuum pump, the inlet of the pure medium micro vacuum pump is fixedly connected to the pure medium input pipe, the pure medium input pipe is connected to an external pure medium holding container, the pure medium micro vacuum pump is placed on the bottom plate of the annular platform, and the pure medium micro vacuum pump is fixedly connected to the upper end surface of the bottom plate of the annular platform.

[0013] The pure medium filling component is responsible for introducing pure medium into the upper device of the measuring gas collecting hood, replacing the water in the measuring device in a 1:2 ratio, so that the upper part of the measuring device is filled with a water column, and starting the pure medium micro vacuum pump. The pure medium input pipe draws pure medium from the external pure medium holding container, and passes through the pure medium micro vacuum pump, the pure medium conduit, the pure medium check valve and the three-way pipe in sequence. Since a straight-through interface of the three-way pipe is connected to a gas collection check valve, the pure medium can only flow to the air guide pipe through the three-way pipe, and then flow to the gas sample storage component, replacing the water in the measuring device in a 1:2 ratio, so that the upper part of the measuring device is filled with a water column.

[0014] Furthermore, the gas collecting hood is an inverted funnel-shaped conical foldable transparent plastic hood.

[0015] The gas collecting hood is an inverted funnel-shaped conical foldable plastic transparent hood. The transparent folding hood is easy to carry, easy to operate, and lightweight. It can realize in-situ observation of the mud-water interface of various aquatic ecosystems in the field environment.

[0016] Furthermore, the gas collecting bottle has a cylindrical shape, and a volume scale is engraved on the body of the gas collecting bottle.

[0017] The gas collection bottle body is engraved with volume scales, which is convenient for real-time observation of the collection situation in the gas collection bottle.

[0018] Furthermore, the power source of the timer, the temperature meter module and the temperature probe is a battery, and the power source of the storage micro vacuum pump and the pure medium micro vacuum pump is a mobile power source.

[0019] The power source of the storage micro vacuum pump and the pure medium micro vacuum pump is a mobile power supply, which is convenient for the mobile use of the entire device. In some remote sampling sites, there can also be power supply, which broadens the scope of application of the device.

[0020] Furthermore, the sample gas transfer interface is connected to a syringe or directly connected to a vacuum sample storage container.

[0021] The sample gas transfer interface is connected to a syringe or directly to a vacuum sample storage container, making the operation easier and achieving the goal of pollution-free sample gas.

[0022] Furthermore, the external pure medium holding container is filled with ultrapure water.

[0023] The pure medium in the pure medium filling component is ultrapure water from the laboratory, which is low in cost, easy to obtain, and convenient and easy to carry.

[0024] Furthermore, the determination method comprises the following steps:

[0025] Step 1: First, assemble the gas collection hood and the stabilizer frame, adjust the height of the gas collection hood inside the stabilizer frame according to the site requirements, and then install the remaining components in sequence to complete the placement of the mud-water interface gas collection assembly;

[0026] Step 2: Connect the second three-way valve to the exhaust port of the collection bottle, and start the storage micro vacuum pump until the inside of the measuring device is completely filled with water column;

[0027] Step 3: Close the second three-way valve, then adjust the first three-way valve to connect the drain port of the collection bottle and the manual pressure reducing tube, and use injection gas until there are no residual bubbles in the gas collection bottle;

[0028] Step 4: Adjust the first three-way valve to connect the two straight-through interfaces, and then connect the power supply of the pure medium micro vacuum pump until the interior of the upper device of the gas collecting hood of the measuring device is filled with pure medium;

[0029] Step 5: Turn off the pure medium micro vacuum pump, keep the first three-way valve unchanged, and turn on the timer and thermometer module.

[0030] Step 1: adjust the height position of the gas collecting hood inside the stabilizing frame to reduce the disturbance effect of the measuring device on the interface. Step 2: discharge the original gas inside the measuring device. Step 3: eliminate the bubbles in the water column filled in the measuring device to further discharge the original gas inside the measuring device. Step 4: replace the water body filling the water column in the measuring device with pure medium. Step 5: the gas pressure on the top of the gas collecting hood gradually exceeds the sum of the valve pressure at the drain port of the collection bottle and the atmospheric pressure. The gas at the mud-water interface enters the gas collection bottle through the air duct to collect and extract the gas released from the mud-water interface. Turn on the timer and thermometer module to collect and record the on-site temperature, time and other information.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] 1. In the design of the gas collection assembly at the mud-water interface of the present invention, a gas collection hood reserves some spacing in the vertical direction of the mud-water interface to reduce the disturbance of the device on the interface during in-situ observation.

[0033] 2. Before collecting gas, the present invention first performs a gas extraction step, fills the device with an observed water body, and then connects a pure medium to replace the observed water body inside the upper end of the gas collecting hood with a pure medium. After completion, all components of the present invention are in a water-filled state, which can ensure that there is no interference from other gases during the gas collection process of the present invention.

[0034] 3. The present invention can visually check the collection progress and collection status during the gas collection process, which is convenient for field operations.

[0035] 4. After the gas is collected, the present invention stores it in the gas storage assembly, and directly loads the collected gas into the gas storage container from the sample gas transfer interface. The whole process is closed and there is no possibility of air contact, which can prevent air from entering and polluting the sample gas.

[0036] 5. The mud-water interface gas collecting hood of this device is a foldable compressed plastic cone hood, which is characterized by light weight, easy to carry and low price.

[0037] 6. The pure medium selected by this device is ultrapure water, which has the characteristics of diverse acquisition channels, convenient and easy to carry, low cost, environmental friendliness and good effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a schematic diagram of the overall structure of a convenient multi-scenario mud-water interface bubbling flux in-situ measurement device and method of the present invention;

[0039] Figure 2 It is a schematic diagram of the lower structure of a convenient multi-scenario mud-water interface bubbling flux in-situ measurement device and method of the present invention;

[0040] Figure 3 It is a schematic diagram of the upper structure of a convenient multi-scenario mud-water interface bubbling flux in-situ measurement device and method of the present invention;

[0041] Figure 4 It is a schematic diagram of the overall structure of the upper part of a convenient multi-scenario mud-water interface bubbling flux in-situ measurement device and method of the present invention;

[0042] Figure 5 This is a schematic diagram of the external structure of a convenient in-situ measurement device and method for bubble flux at the mud-water interface that can be used in multiple scenarios according to the present invention.

[0043] In the figure: 1. mud-water interface gas collection component; 2. gas sample storage component; 3. pure medium filling component; 11. stabilizing frame; 12. temperature probe; 13. pull ring; 14. gas collecting hood; 15. air guide tube; 16. gas collection one-way valve; 17. three-way pipe; 18. upper shelf; 19. lower shelf; 110. positioning column; 21. gas collection bottle; 22. collection bottle air inlet; 23. collection bottle exhaust port; 24. collection bottle fixing frame; 25. storage micro vacuum pump; 26. rubber air cushion; 27. exhaust pipe; 28. first three-way valve; 29. ​​bottom plate of circular platform; 210. collection bottle drain port; 211. timer and thermometer module; 212. manual pressure reducing pipe; 213. storage one-way valve; 214. second three-way valve; 31. pure medium one-way valve; 32. pure medium conduit; 33. pure medium micro vacuum pump; 34. pure medium input pipe. DETAILED DESCRIPTION

[0044] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making any creative work shall fall within the scope of protection of the present invention.

[0045] Example: Figure 1-Figure 5 As shown, the present invention provides a convenient multi-scenario mud-water interface bubbling flux in-situ measurement device and method technical solution:

[0046] like Figure 5 As shown, the measuring device includes a mud-water interface gas collecting component 1, a gas sample storage component 2 and a pure medium filling component 3, wherein the mud-water interface gas collecting component 1 and one end of the pure medium filling component 3 are fixedly connected, the gas sample storage component 2 and the mud-water interface gas collecting component 1 are fixedly connected, the pure medium filling component 3 passes through the gas sample storage component 2, and part of the pure medium filling component 3 and the gas sample storage component 2 are fixedly connected.

[0047] The mud-water interface gas collection component 1 is responsible for inserting into the sediment to reduce the interface disturbance intensity caused by water flow movement and further collect the mud-water interface gas. The gas sample storage component 2 first discharges the original gas inside the measuring device to fill the water column inside the measuring device. The pure medium filling component 3 replaces the water body inside the measuring device in a 1:2 ratio to fill the water column inside the measuring device. The gas sample storage component 2 then replaces the water body in the filled water column with the collected mud-water interface gas in a 1:1 ratio to achieve the collection and extraction of mud-water interface gas.

[0048] like Figure 1 and Figure 2As shown, the mud-water interface gas collection assembly 1 includes a stabilizing frame 11, a temperature probe 12, a pull ring 13, a gas collecting hood 14, an air guide pipe 15, a gas collecting non-return valve 16 and a three-way pipe 17. The stabilizing frame 11 is divided into an upper frame 18 and a lower frame 19. The upper end surface of the lower frame 19 is provided with a threaded hole and a positioning column 110. The upper frame 18 is provided with a threaded through hole at a position corresponding to the threaded hole of the lower frame 19. The pull ring 13 is threadedly connected to the upper frame 18. The pull ring 13 passes through the threaded through hole of the upper frame 18 and is threadedly connected to the lower frame 19. A positioning hole is provided at the bottom end of the gas collecting hood 14. The positioning column 110 passes through the positioning hole of the gas collecting hood 14. The bottom part of the gas collecting hood 1 4 is located between the upper frame 18 and the lower frame 19, the gas collecting hood 14 is slidably connected to the positioning column 110, the temperature probe 12 is fixedly connected to the upper end surface of the bottom end of the gas collecting hood 14, the temperature probe 12 is electrically connected to the gas sample storage assembly 2, the gas collection one-way valve 16 is sealed and connected to the exhaust port at the upper end of the gas collecting hood 14, one straight-through interface of the three-way pipe 17 is fixedly connected to the gas collection one-way valve 16, the other straight-through interface of the three-way pipe 17 is fixedly connected to one end of the air guide tube 15, the corner interface of the three-way pipe 17 is fixedly connected to the pure medium filling assembly 3, and the other interface of the air guide tube 15 is fixedly connected to the gas sample storage assembly 2.

[0049] First, install the gas collecting hood 14 and the stabilizing frame 11, and then adjust the height position of the gas collecting hood 14 inside the stabilizing frame 11 according to actual needs to realize in-situ observation of the mud-water interface of various aquatic ecosystems in the field environment. The mud-water interface gas flows upward from the bottom of the gas collecting hood 14 through the top air outlet of the gas collecting hood 14. Since the gas collection one-way valve 16 is connected to the top air outlet of the gas collecting hood 14, the mud-water interface gas can only pass from the top air outlet of the gas collecting hood 14 to the three-way pipe 17, and the three-way pipe 17 then transports the mud-water interface gas to the air guide pipe 15, and finally to the gas sample storage assembly 2.

[0050] like Figure 1 , Figure 3 and Figure 4As shown, the gas sample storage component 2 includes a gas collecting bottle 21, a collecting bottle air inlet 22, a collecting bottle exhaust port 23, a collecting bottle fixing frame 24, a storage micro vacuum pump 25, a rubber air cushion 26, an exhaust pipe 27, a first three-way valve 28, a circular platform bottom plate 29, a collecting bottle drain port 210, a timer and thermometer module 211, a manual pressure reducing pipe 212, a storage one-way valve 213 and a second three-way valve 214, the circular platform bottom plate 29 and the rubber air cushion 26 are fixedly connected, the circular platform bottom plate 29 is located in the inner circle of the rubber air cushion 26, the timer and thermometer module 211 is fixedly connected to the upper end surface of the circular platform bottom plate 29, the timer and thermometer module 211 is electrically connected to the temperature probe 12, part of the pure medium filling component 3 is fixedly connected to the upper end surface of the circular platform bottom plate 29, the collecting bottle fixing frame 24 is fixedly connected to the upper end surface of the circular platform bottom plate 29, The central axis of the collecting bottle fixing frame 24 coincides with the central axis of the bottom plate 29 of the circular platform, the upper end of the collecting bottle fixing frame 24 is a circular ring, the gas collecting bottle 21 is placed in the circular ring at the upper end of the collecting bottle fixing frame 24, the collecting bottle air inlet 22 is fixedly connected to the air guide tube 15, the collecting bottle drain outlet 210 is fixedly connected to the inlet of the storage one-way valve 213, a straight-through interface of the first three-way valve 28 is fixedly connected to the outlet of the storage one-way valve 213, the corner interface of the first three-way valve 28 is fixedly connected to the manual pressure reducing pipe 212, the collecting bottle exhaust port 23 is fixedly connected to a straight-through interface of the second three-way valve 214, the other straight-through interface of the second three-way valve 214 is a sample gas transfer interface, the corner interface of the second three-way valve 214 is fixedly connected to one end of the exhaust pipe 27, and the other end of the exhaust pipe 27 is fixedly connected to the water inlet of the storage micro vacuum pump 25.

[0051] After the installation and placement of the mud-water interface gas collection component 1 is completed, the second three-way valve 214 is connected to the collection bottle exhaust port 23, and the storage micro vacuum pump 25 is started to evacuate the residual gas inside the measuring device until the measuring device is completely filled with water column. After completion, the second three-way valve 214 is closed, and then the first three-way valve 28 is adjusted to connect the collection bottle drain port 210 and the manual decompression pipe 212, and manual decompression is performed using injection gas. After observing that there are no residual bubbles in the gas collection bottle 21, the first three-way valve 28 is adjusted to connect the two straight-through interfaces to achieve automatic drainage, and then the pure medium filling component 3 is started to replace 2 times the volume of the water body inside the upper device of the gas collection cover 14. The water body in the replaced gas collection bottle 21 is discharged through the collection bottle drain port 210. The gas is replaced and discharged in a volume ratio of 1:1, so that the interior of the upper device of the gas collecting hood 14 of the measuring device is filled with pure medium. Finally, the pure medium filling component 3 is closed, and the first three-way valve 28 remains unchanged. Since the measuring device is sealed as a whole, the collection bottle drain port 210 is a one-way passage due to the storage check valve 213. The water in the gas collecting bottle 21 will not flow back and fall due to gravitational potential energy. However, as the gas at the mud-water interface is gradually collected by the gas collecting hood 14 and aggregated at the top of the gas collecting hood 14, it is affected by the water pressure at the mud-water interface. At this time, the gas pressure at the top of the gas collecting hood 14 will be greater than the sum of the valve pressure at the collection bottle drain port 210 and the atmospheric pressure, so that the gas will enter the gas collecting bottle 21 through the air duct 15, thereby collecting and extracting the gas released from the mud-water interface.

[0052] like Figure 1 and Figure 3 As shown, the pure medium filling component 3 includes a pure medium one-way valve 31, a pure medium conduit 32, a pure medium micro vacuum pump 33 and a pure medium input pipe 34, one end of the pure medium conduit 32 is fixedly connected to the corner interface of the three-way pipe 17, the other end of the pure medium conduit 32 is fixedly connected to the outlet of the pure medium micro vacuum pump 33, the inlet of the pure medium micro vacuum pump 33 is fixedly connected to the pure medium input pipe 34, the pure medium input pipe 34 is connected to an external pure medium holding container, the pure medium micro vacuum pump 33 is placed on the bottom plate 29 of the annular platform, and the pure medium micro vacuum pump 33 is fixedly connected to the upper end surface of the bottom plate 29 of the annular platform.

[0053] The pure medium filling component 3 is responsible for introducing pure medium into the upper device of the measuring gas collecting hood 14, replacing the water in the measuring device in a 1:2 ratio, so that the upper part of the measuring device is filled with a water column, and starting the pure medium micro vacuum pump 33. The pure medium input pipe 34 draws pure medium from the external pure medium holding container, and passes through the pure medium micro vacuum pump 33, the pure medium conduit 32, the pure medium check valve 31 and the three-way pipe 17 in sequence. Since a straight-through interface of the three-way pipe 17 is connected to the gas collection check valve 16, the pure medium can only flow to the air guide pipe 15 through the three-way pipe 17, and then flow to the gas sample storage component 2, replacing the water in the measuring device in a 1:2 ratio, so that the upper part of the measuring device is filled with a water column.

[0054] like Figure 2 As shown, the gas collecting cover 14 is an inverted funnel-shaped conical foldable transparent plastic cover.

[0055] The gas collecting hood 14 is an inverted funnel-shaped conical foldable plastic transparent hood. The transparent foldable hood is convenient to carry, easy to operate, and lightweight, and can realize in-situ observation of mud-water interfaces of various aquatic ecosystems in the field environment.

[0056] like Figure 3 As shown, the gas collection bottle 21 is cylindrical in shape, and the body of the gas collection bottle 21 is engraved with volume scales.

[0057] The body of the gas collection bottle 21 is engraved with volume scales, which facilitates real-time observation of the collection situation in the gas collection bottle 21.

[0058] The power source of the timer and thermometer module 211 and the temperature probe 12 is a battery, and the power source of the storage micro vacuum pump 25 and the pure medium micro vacuum pump 33 is a mobile power source.

[0059] The power source of the storage micro vacuum pump 25 and the pure medium micro vacuum pump 33 is a mobile power source, which is convenient for the mobile use of the entire device. In some remote sampling locations, there can also be power supply, which broadens the scope of application of the device.

[0060] The sample gas transfer interface is connected to a syringe or directly to a vacuum sample storage container.

[0061] The sample gas transfer interface is connected to a syringe or directly to a vacuum sample storage container, making the operation easier and achieving the goal of pollution-free sample gas.

[0062] The external pure medium container is filled with ultrapure water.

[0063] The pure medium in the pure medium filling component 3 is ultrapure water from a laboratory, which is low-cost, easily available, and convenient to carry.

[0064] The determination method comprises the following steps:

[0065] Step 1: First, assemble the gas collecting hood 14 and the stabilizing frame 11, adjust the height of the gas collecting hood 14 inside the stabilizing frame 11 according to the site requirements, and then install the remaining components in sequence to complete the placement of the mud-water interface gas collection assembly 1;

[0066] Step 2: connect the second three-way valve 214 and the exhaust port 23 of the collection bottle, and start the storage micro vacuum pump 25 until the inside of the measuring device is completely filled with water column;

[0067] Step 3: Close the second three-way valve 214, then adjust the first three-way valve 28 to connect the collection bottle drain port 210 and the manual pressure reducing pipe 212, and use injection gas until there are no residual bubbles in the gas collection bottle 21;

[0068] Step 4: Adjust the first three-way valve 28 to connect the two straight-through interfaces, and then connect the power supply of the pure medium micro vacuum pump 33 until the upper device of the measuring device gas collecting cover 14 is completely filled with pure medium;

[0069] Step 5: Turn off the pure medium micro vacuum pump 33, keep the first three-way valve 28 unchanged, and turn on the timer and thermometer module 211.

[0070] Step one is to adjust the height position of the gas collecting hood 14 inside the stabilizing frame 11 to reduce the disturbance effect of the measuring device on the interface. Step two is to discharge the original gas inside the measuring device. Step three is to eliminate the bubbles in the water column filled in the measuring device to further discharge the original gas inside the measuring device. Step four is to replace the water body filling the water column in the measuring device with a pure medium. Step five is to gradually make the gas pressure at the top of the gas collecting hood 14 greater than the sum of the valve pressure at the drain port 210 of the collection bottle and the atmospheric pressure. The gas at the mud-water interface enters the gas collection bottle 21 through the air duct 15 to collect and extract the gas released from the mud-water interface. Turn on the timer and thermometer module 211 to collect and record the on-site temperature, time and other information.

[0071] Working principle of the present invention: When using the present invention, first install and combine the gas collecting hood 14 and the stabilizing frame 11, adjust the height position of the gas collecting hood 14 inside the stabilizing frame 11 according to on-site requirements, then install the remaining components in sequence, tie the lifting rope to the pull ring 13, then slowly insert the four sharp corners of the stabilizing frame 11 into the sediment, complete the placement of the mud-water interface gas collection assembly, then connect the second three-way valve 214 and the collection bottle exhaust port 23, start the storage micro-vacuum pump 25 to evacuate the residual gas inside the measuring device until the measuring device is completely filled with water column inside, after completion, close the second three-way valve 214, then adjust the first three-way valve 28 to connect the collection bottle drain port 210 and the manual decompression pipe 212, use injection gas for manual decompression, observe that there are no residual bubbles in the gas collection bottle 21, adjust the first three-way valve 28 to connect the two straight-through interfaces to achieve automatic drainage, then connect the pure medium micro-vacuum pump 33 to the power supply, introduce pure medium, replace the gas collecting hood 14 The volume of the water in the replaced gas collection bottle 21 is 2 times that of the water in the device, and the water in the replaced gas collection bottle 21 is replaced and discharged through the collection bottle drain port 210 at a volume ratio of 1:1, so that the interior above the device collection check valve 16 is filled with pure medium, and finally the pure medium micro vacuum pump 33 is closed, and the first three-way valve 28 remains unchanged. Since the measuring device is sealed as a whole, the collection bottle drain port 210 is a one-way passage due to the storage check valve 213, and the water in the gas collection bottle 21 will not flow back and fall due to gravitational potential energy. However, as the gas at the mud-water interface is gradually collected by the gas collecting hood 14, after being aggregated at the top of the gas collecting hood 14, it is affected by the water pressure at the mud-water interface. At this time, the gas pressure at the top of the gas collecting hood 14 will be greater than the sum of the valve pressure at the collection bottle drain port 210 and the atmospheric pressure, so that the gas will enter the gas collection bottle 21 through the air guide tube 15, so as to collect and extract the gas released from the mud-water interface. According to the experimental requirements, the timer and thermometer module 211 are turned on to collect and record the on-site temperature, time and other information in real time.

[0072] In order to carry out field application and testing of the present invention, large natural lakes, natural rivers and artificial breeding ponds were selected for field test experiments. The experiments were carried out on July 17, August 3 and August 9, 2024, respectively, in Taihu Lake, a large natural lake in Wuxi City, Jiangsu Province, Jiuxiang River, a natural river in Nanjing City, Jiangsu Province, and an artificial bream breeding pond in Changzhou City, Jiangsu Province.

[0073] The present invention discloses a convenient in-situ determination device and method for bubbling flux at mud-water interface for use in multiple scenarios. On-site experimental testing is an important verification experiment. Before the experimental device is deployed, an environmental assessment is first conducted on the collection site to ensure that the selected site meets the applicable water depth, flow rate and sediment characteristics of the device. After the sampling experimental point is determined, the device is assembled according to the steps described in the aforementioned specific implementation method, and then the gas collection device is slowly placed underwater at the observation point to complete the deployment. To ensure smooth sample gas collection, the device is left to stand for 20 minutes before formal collection to adjust to the optimal working state, and bubbling gas is started to be collected. During the entire collection process, the changes in the headspace in the gas collection bottle are observed at intervals, and the device performance and related data are recorded. After the collection is completed, the sample gas storage component is quickly closed, and then the collected gas is collected into a vacuum vial containing 2g KCL through the sample gas transfer interface and brought back to the laboratory for detection. The sample gas content analysis is performed by a gas chromatograph (GC / FID, 7890B, Agilent) equipped with a flame ionization detector.

[0074] The present invention can accurately capture the gas bubbling at the sediment-water interface, and quantify the gas collection rate and the sediment-water interface bubbling flux. The observation results are shown in Table 1. By comparing the sediment-water interface fluxes of three greenhouse gases, it is found that the CH4 flux is the highest and the N2O flux is the lowest. There are orders of magnitude differences among the three gases. It is speculated that CH4 is mainly released in the form of bubbling at the sediment-water interface. Comparison of the experimental results of the three water body types shows that the greenhouse gas release flux at the sediment-water interface of natural water bodies is much smaller than that of artificial breeding ponds, and this may be related to human factors such as feed input in artificial breeding ponds.

[0075] The field use results of the device of the present invention show that it is possible to observe and analyze the gas bubbling flux at the sediment-water interface, including but not limited to greenhouse gases, thus achieving the inventive expectations of the present invention.

[0076] Table 1 Observation results of a convenient multi-scenario mud-water interface bubbling flux in-situ measurement device

[0077]

[0078] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A convenient multi-scenario mud-water interface bubbling flux in-situ measurement device, Features: The measuring device comprises a mud-water interface gas collecting component (1), a gas sample storage component (2) and a pure medium filling component (3); the mud-water interface gas collecting component (1) and the pure medium filling component (3) are fixedly connected at one end, the gas sample storage component (2) and the mud-water interface gas collecting component (1) are fixedly connected, the pure medium filling component (3) passes through the gas sample storage component (2), and part of the pure medium filling component (3) and the gas sample storage component (2) are fixedly connected.

2. A portable multi-scenario mud-water interface bubbling flux in-situ measurement device according to claim 1, Features: The mud-water interface gas collection assembly (1) comprises a stabilizing frame (11), a temperature probe (12), a pull ring (13), a gas collecting hood (14), an air guide tube (15), a gas collecting non-return valve (16) and a three-way pipe (17); the stabilizing frame (11) is divided into an upper frame (18) and a lower frame (19); a threaded hole and a positioning column (110) are arranged on the upper end surface of the lower frame (19); a threaded through hole is arranged on the upper frame (18) at a position corresponding to the threaded hole of the lower frame (19); the pull ring (13) is threadedly connected to the upper frame (18); the pull ring (13) passes through the threaded through hole of the upper frame (18) and is threadedly connected to the lower frame (19); a positioning hole is arranged at the bottom end of the gas collecting hood (14); the positioning column (110) passes through the positioning hole of the gas collecting hood (14); the bottom end of the gas collecting hood (14) is provided with a positioning hole; The gas hood (14) is located between the upper frame (18) and the lower frame (19), the gas collecting hood (14) and the positioning column (110) are slidably connected, the temperature probe (12) and the upper end surface of the bottom end of the gas collecting hood (14) are fixedly connected, the temperature probe (12) and the gas sample storage assembly (2) are electrically connected, the gas collection one-way valve (16) and the exhaust port at the upper end of the gas collecting hood (14) are sealed and connected, a straight-through interface of the three-way pipe (17) and the gas collection one-way valve (16) are fixedly connected, another straight-through interface of the three-way pipe (17) and one end of the air guide pipe (15) are fixedly connected, the corner interface of the three-way pipe (17) and the pure medium filling assembly (3) are fixedly connected, and the other interface of the air guide pipe (15) is fixedly connected to the gas sample storage assembly (2).

3. A portable multi-scenario mud-water interface bubbling flux in-situ measurement device according to claim 2, Features: The gas sample storage assembly (2) comprises a gas collection bottle (21), a collection bottle air inlet (22), a collection bottle exhaust port (23), a collection bottle fixing frame (24), a storage micro vacuum pump (25), a rubber air cushion (26), an air extraction pipe (27), a first three-way valve (28), a circular platform bottom plate (29), a collection bottle drain port (210), a timer and a thermometer module (211), a manual pressure reducing pipe (212), a storage one-way valve (213) and a second three-way valve (214), wherein the The annular platform bottom plate (29) is fixedly connected to the rubber air cushion (26), the annular platform bottom plate (29) is located in the inner circle of the rubber air cushion (26), the timer and temperature gauge module (211) is fixedly connected to the upper end surface of the annular platform bottom plate (29), the timer and temperature gauge module (211) is electrically connected to the temperature probe (12), part of the pure medium filling component (3) is fixedly connected to the upper end surface of the annular platform bottom plate (29), the collecting bottle fixing frame (24) is fixedly connected to the upper end surface of the annular platform bottom plate (29), The end faces are fixedly connected, the central axis of the collecting bottle fixing frame (24) coincides with the central axis of the circular platform bottom plate (29), the upper end of the collecting bottle fixing frame (24) is a circular ring, the gas collecting bottle (21) is placed in the circular ring at the upper end of the collecting bottle fixing frame (24), the collecting bottle air inlet (22) is fixedly connected to the air guide pipe (15), the collecting bottle water outlet (210) is fixedly connected to the inlet of the storage check valve (213), a straight-through interface of the first three-way valve (28) and the storage check valve (213) outlet is fixedly connected, the corner interface of the first three-way valve (28) is fixedly connected to the manual pressure reducing tube (212), the exhaust port (23) of the collecting bottle is fixedly connected to a straight interface of the second three-way valve (214), the other straight interface of the second three-way valve (214) is a sample gas transfer interface, the corner interface of the second three-way valve (214) is fixedly connected to one end of the exhaust pipe (27), and the other end of the exhaust pipe (27) is fixedly connected to the water inlet of the storage micro vacuum pump (25).

4. A portable multi-scenario mud-water interface bubbling flux in-situ measurement device according to claim 3, Features: The clean medium filling component (3) comprises a clean medium one-way valve (31), a clean medium conduit (32), a clean medium micro vacuum pump (33) and a clean medium input pipe (34); one end of the clean medium conduit (32) is fixedly connected to the corner interface of the three-way pipe (17); the other end of the clean medium conduit (32) is fixedly connected to the outlet of the clean medium micro vacuum pump (33); the inlet of the clean medium micro vacuum pump (33) is fixedly connected to the clean medium input pipe (34); the clean medium input pipe (34) is connected to an external clean medium container; the clean medium micro vacuum pump (33) is placed on the bottom plate of the circular platform (29); and the clean medium micro vacuum pump (33) is fixedly connected to the upper end surface of the bottom plate of the circular platform (29).

5. A portable multi-scenario mud-water interface bubbling flux in-situ measurement device according to claim 4, Features: The gas collecting hood (14) is an inverted funnel-shaped conical foldable transparent plastic hood.

6. A portable multi-scenario mud-water interface bubbling flux in-situ measurement device according to claim 5, Features: The gas collection bottle (21) has a cylindrical shape, and a volume scale is engraved on the body of the gas collection bottle (21).

7. A portable multi-scenario mud-water interface bubbling flux in-situ measurement device according to claim 6, Features: The power source of the timer and thermometer module (211) and the temperature probe (12) is a battery, and the power source of the storage micro vacuum pump (25) and the pure medium micro vacuum pump (33) is a mobile power source.

8. A portable multi-scenario mud-water interface bubbling flux in-situ measurement device according to claim 7, Features: The sample gas transfer interface is connected to a syringe or directly connected to a vacuum sample storage container.

9. A portable multi-scenario mud-water interface bubbling flux in-situ measurement device according to claim 8, Features: The external pure medium holding container is filled with ultrapure water.

10. A method for measuring the in-situ measurement of the bubbling flux at the mud-water interface using the portable multi-scenario measurement device of claim 9, Features: The determination method comprises the following steps: Step 1: first assemble the gas collecting hood (14) and the stabilizing frame (11), adjust the height of the gas collecting hood (14) inside the stabilizing frame (11) according to the site requirements, and then install the remaining components in sequence to complete the placement of the mud-water interface gas collection assembly (1); Step 2: connect the second three-way valve (214) and the exhaust port (23) of the collection bottle, and start the storage micro vacuum pump (25) until the interior of the measuring device is completely filled with water column; Step 3: Close the second three-way valve (214), then adjust the first three-way valve (28) to connect the collection bottle drain port (210) and the manual pressure reducing pipe (212), and use injection gas until there are no residual bubbles in the gas collection bottle (21); Step 4: Adjust the first three-way valve (28) to connect the two straight-through interfaces, and then connect the power supply of the pure medium micro vacuum pump (33) until the upper device of the measuring device gas collecting cover 14 is completely filled with pure medium; Step 5: Turn off the pure medium micro vacuum pump (33), keep the first three-way valve (28) unchanged, and turn on the timer and temperature meter module (211).

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