An in-situ testing system for sediment pore water chemical parameters

Abstract

The present invention discloses an in-situ testing system for sediment pore water chemical parameters, comprising a docking fixture, an electric push rod, a guide rail, a connecting rod, a probe, a perforated rubber cover, a large end cap, a microelectrode connector, a small end cap, a copper tube, a water collection funnel, a permeable ceramic, a microelectrode assembly, a fixing sleeve, a flange, an electronics compartment, a connecting block, a submersible pump, and a three-way valve. Based on microelectrode detection technology, the present invention employs an electric push rod to achieve stable vertical displacement of the probe, passively collects pore water through the permeable ceramic, and replaces pore water samples through a pump and valve. The system is used to continuously detect chemical parameters such as pH, H2S, and Eh in marine sediment pore water. The present invention has the advantages of a simple and reliable structure, low cost, strong environmental adaptability, low disturbance, easily replaceable parts, high precision, and high efficiency.

Description

Technical Field

[0001] The present invention belongs to the technical field of sediment detection, and relates to a testing device that utilizes a motor to drive a ball screw, which is mainly suitable for in-situ detection of multiple chemical parameters of pore water in nearshore mudflats or shallow sea sediments. Background Art

[0002] The chemical composition of sediment pore water can reveal the nature and deposition rate of materials buried contemporaneously with the sediment, as well as the processes of diffusion, migration, and chemical reactions between seawater and sediment. Changes in the chemical composition of sediment pore water are influenced by the deposition rate, redox potential, and the organic matter content of the sediment, and are therefore of great biogeochemical significance. During operation, sediment pore water chemical parameter testing systems can typically be fixedly mounted on a large underwater in-situ testing system, such as a test stand or seabed foundation, for in-situ detection of sediment pore water chemical parameters. Field work conditions are challenging, often requiring testing equipment that is efficient, simple, reliable, easy to maintain, with easily replaceable parts, and adaptable to harsh field environments. Furthermore, the pore water chemical parameter testing process must minimize environmental disturbance. Current pore water chemical parameter testing typically requires collecting sediment, then using a sampler in the laboratory to collect pore water for in-house analysis. This method often involves complex procedures and samples are susceptible to contamination during transportation. Summary of the Invention

[0003] In order to overcome the shortcomings of the existing technology, the purpose of the present invention is to provide an in-situ testing system for sediment pore water chemical parameters, which meets the needs of in-situ detection of marine sediment pore water chemical parameters. The operation steps are relatively simple, the requirements for operators are low, and the detection process has little disturbance to the environment and high detection efficiency.

[0004] The object of the present invention is achieved through the following technical solutions:

[0005] An in-situ test system for sediment pore water chemical parameters, comprising a docking fixture, an electric push rod, a guide rail, a connecting rod, a probe rod, a perforated rubber cover, a large end cap, a microelectrode connector, a small end cap, a copper tube, a water collection funnel, a permeable ceramic, a microelectrode group, a fixing sleeve, a flange, an electronic compartment, a connecting block, a submersible pump, and a three-way valve;

[0006] The electric push rod and the guide rail are installed on the docking fixing frame; one end of the connecting rod is fixedly connected to the electric push rod, and the other end is fixedly connected to the connecting block; one end of the connecting block is fixedly connected to the electronic compartment, and the other end is fixedly connected to the electric push rod; one end of the large end cover is installed on the electronic compartment, and the other end is connected to the flange; one end of the small end cover is installed on the flange, and the other end is connected to the fixed sleeve; the microelectrode connector is fixed on the small end cover, and the microelectrode group is installed on the microelectrode connector, and the data wire is led out through the microelectrode connector and introduced into the electronic compartment through the perforated rubber cover; the top of the probe rod The probe is cylindrical with a hollow cavity inside. The microelectrode group extends deep into the probe. The wall of the probe is provided with multiple holes, and the bottom end is a pointed cone, which is convenient for penetrating marine sediments. The permeable ceramic is placed on the inside of the probe for in-situ passive collection of sediment pore water samples. The fixed sleeve is pressed into the probe to compact the permeable ceramic placed on the inner wall of the probe. One end of the copper tube is connected to the water collecting funnel, and is led out through the small end cover via a flange to connect to the lower end of the submersible pump. The submersible pump is installed on a docking fixing frame, one end of which is connected to the copper tube and the other end is connected to the three-way valve.

[0007] The docking fixing frame panel is provided with four through holes at the upper and lower ends respectively, and is fixed to a large underwater in-situ test system such as a test bracket or a seabed base by bolts and nuts.

[0008] When the electric push rod is driven by the motor to move the ball screw upward or downward within the working stroke, it drives the connecting block to move upward or downward stably along the guide rail in the vertical direction.

[0009] The probe rod is provided with neatly arranged rectangular holes. When the probe rod enters the sediment, pore water passes through the rectangular holes on the probe rod wall and is passively collected into the probe rod cavity through the permeable ceramic.

[0010] The microelectrode group can be an electrochemical electrode such as pH, Ag / AgCl, Ag / Ag2S, Eh, dissolved oxygen, sulfate, carbonate, etc., which is fixed on the microelectrode joint by welding and can detect multiple chemical parameters of marine sediment pore water.

[0011] The water collecting funnel is designed as a Klein bottle style. The opening at the bottom of the water collecting funnel is connected to one end of the copper tube, and the opening on the side wall of the water collecting funnel is connected to the other end of the copper tube to ensure that the sample is completely replaced.

[0012] The submersible pump is connected to the three-way valve. When the pore water sample test is completed, the submersible pump switch is turned on, the pore water in the probe rod is pumped to the submersible pump, and the three-way valve automatically opens to discharge the pore water.

[0013] The advantages and positive effects of the present invention are:

[0014] 1. Low disturbance: The tip of the pore water chemical parameter testing system designed in the present invention is conical and has a small diameter. During the insertion into the sediment, the disturbance to the pore water outside the sediment is small.

[0015] 2. Reliable structure: The pore water chemical parameter testing system designed in the present invention adopts a ball screw transmission structure with high transmission efficiency and stable output, and uses mostly regular parts such as rods and plates, which are easy to process, easy to assemble and disassemble, and have a reliable structure.

[0016] 3. Low cost: The parts of the pore water chemical parameter testing system designed by the present invention are easy to process and have low processing costs; bolts, nuts and other connection methods can be used, and the assembly cost is low.

[0017] 4. Strong environmental adaptability: The pore water chemical parameter testing system designed by the present invention has no complicated transmission parts. All connections are fixed with bolts and nuts, and are sealed with threads, rubber materials, O-rings, waterproof sealants, etc. It can be exposed in seawater and does not require an additional protective shell.

[0018] 5. Easy replacement of parts: The parts of the pore water chemical parameter testing system designed by the present invention are easy to replace. The structures of different microelectrodes and their supporting electronic compartments are independent of each other, and damaged parts can be replaced independently.

[0019] 6. High Precision and Efficiency: The pore water chemical parameter testing system designed in this invention is driven by a motor and employs a ball screw structure. It can convert rotational motion or torque into linear motion. The motor-driven process provides stable output force and low friction, resulting in high precision and efficiency. During sample replacement, a submersible pump and three-way valve are used in conjunction, ensuring high testing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the in-situ testing system for sediment pore water chemical parameters.

[0021] Figure 2 A partial enlarged view of the in-situ testing system for sediment pore water chemical parameters.

[0022] Figure 3 Isometric diagram of the in-situ test system for sediment pore water chemical parameters-1.

[0023] Figure 4 Isometric diagram of the in-situ test system for sediment pore water chemical parameters-2.

[0024] Figure 5 Front view of the in-situ testing system for sediment pore water chemical parameters.

[0025] Figure 6 Side view of the in-situ testing system for sediment pore water chemical parameters.

[0026] Figure 7 Top view of the in-situ testing system for sediment pore water chemical parameters.

[0027] Among them: 1 is the docking fixing frame, 2 is the electric push rod, 3 is the guide rail, 4 is the connecting rod, 5 is the probe rod, 6 is the perforated cover, 7 is the large end cover, 8 is the microelectrode connector, 9 is the small end cover, 10 is the copper tube, 11 is the water collecting funnel, 12 is the permeable ceramic, 13 is the microelectrode group, 14 is the fixing sleeve, 15 is the flange, 16 is the electronic compartment, 17 is the connecting block, 18 is the submersible pump, and 19 is the three-way valve. DETAILED DESCRIPTION

[0028] The present invention will be further described below with reference to the accompanying drawings and examples.

[0029] like Figures 1 to 7 As shown, the present invention includes a docking fixing frame 1, an electric push rod 2, a guide rail 3, a connecting rod 4, a probe rod 5, a perforated rubber cover 6, a large end cover 7, a microelectrode connector 8, a small end cover 9, a copper tube 10, a water collecting funnel 11, a permeable ceramic 12, a microelectrode group 13, a fixing sleeve 14, a flange 15, an electronic compartment 16, a connecting block 17, a submersible pump 18, and a three-way valve 19. Among them, the electric push rod 2 and the guide rail 3 are respectively installed on the docking fixing frame 1; one end of the connecting rod 4 is fixedly connected to the electric push rod 2, and the other end is fixedly connected to the connecting block 17; one end of the connecting block 17 is fixedly connected to the electronic compartment 16, and the other end is fixedly connected to the electric push rod 2; one end of the large end cover 7 is installed on the electronic compartment 16, and the other end is connected to the flange 15; one end of the small end cover 9 is installed on the flange 15, and the other end is connected to the fixed sleeve 14; the microelectrode connector 8 is fixed on the small end cover 9, the microelectrode group 13 is installed on the microelectrode connector 8, and the data wire is led out through the microelectrode connector 8 and introduced into the electronic compartment 16 through the perforated rubber cover 6; the probe 5 The top is fixedly mounted on the small end cap 9, the probe rod 5 is cylindrical with a hollow cavity inside, the microelectrode group 13 penetrates into the interior of the probe rod 5, a plurality of holes are provided on the wall of the probe rod 5, and the bottom end is a pointed cone, which is convenient for penetrating marine sediments; the permeable ceramic 12 is placed on the inside of the probe rod 5 for in-situ passive collection of sediment pore water samples; the fixed sleeve 14 is pressed into the probe rod 5, pressing the permeable ceramic 12 placed on the inner wall of the probe rod 5; one end of the copper tube 10 is connected to the water collecting funnel 11, passes through the small end cap 9, and is led out through the flange 15 to connect to the lower end of the submersible pump; the submersible pump 18 is installed on the docking fixing frame 1, one end is connected to the copper tube 10, and the other end is connected to the three-way valve 19.

[0030] In this embodiment, four through holes are respectively provided at the upper and lower ends of the panel of the docking fixing frame 1, and it is fixed to a large underwater in-situ testing system such as a test bracket or a seabed foundation by bolts and nuts.

[0031] In this embodiment, the driving module is an electric push rod 2. When the motor drives the ball screw to move within the working stroke, it drives the connecting block 17 to move stably in the vertical direction along the guide rail 3.

[0032] In this embodiment, the probe rod 5 is provided with a plurality of neatly arranged rectangular holes. When the probe rod 5 enters the sediment, pore water passes through the rectangular holes on the wall of the probe rod 5 and is passively collected into the cavity of the probe rod 5 through the permeable ceramic 12.

[0033] In this embodiment, the microelectrode group 13 is fixed to the microelectrode connector 8 by welding, and is used to detect various chemical parameters of pore water in marine sediments.

[0034] In this embodiment, the water collecting funnel 11 is designed as a Klein bottle style. The bottom opening of the water collecting funnel 11 is connected to one end of the copper tube 10, and the side wall opening of the water collecting funnel 11 is connected to the other end of the copper tube 10, ensuring that the sample can be completely replaced before re-measurement.

[0035] The working principle of the present invention is:

[0036] When the motor drives the ball screw to move downward within the working stroke of the electric push rod 2, it drives the connecting block 17 to move downward stably along the guide rail 3 in the vertical direction, and drives the lower part of the probe rod 5 to insert into the sediment. The pore water sample quickly passes through the rectangular hole on the wall of the probe rod 5, passively penetrates into the detection cavity of the probe rod 5 through the permeable ceramic 12, and uses the microelectrode group 13 to detect various chemical parameters of the pore water. The data signal is transmitted to the terminal via the data acquisition and processing system of the electronic warehouse 16 via the data cable.

[0037] When the motor drives the ball screw to move upward within the working stroke of the electric push rod 2, it causes the connecting block 17 to move upward and stably along the guide rail 3 in the vertical direction, thereby driving the probe 5 to extract the sediment, and the test is completed. The switch of the submersible pump 18 is turned on, and the pore water sample inside the probe 5 is collected by the water collection funnel 11 and pumped to the submersible pump 18 through the copper tube 10. When the three-way valve 19 senses the pressure, it automatically opens, and all the pore water is discharged from the test system, ready for the next test.

[0038] An application example of the present invention is:

[0039] When conducting in-situ pore water chemical parameter testing nearshore, the pore water testing device is fixed to the support of a large underwater in-situ testing system, such as a seabed foundation, using bolts and nuts through the through-holes in the docking fixture 1. A motor drives the ball screw downward within the working stroke of the pressure-resistant electric push rod 2, driving the connecting block 17 to move vertically and steadily downward along the guide rail 3. Simultaneously, the probe 5 is inserted downward into the sediment. Pore water passes through the rectangular hole in the probe 5, is filtered by the permeable ceramic 12, and is collected within the probe 5. Various pore water chemical parameters are measured using the microelectrode array 13. The obtained signals are transmitted to the electronic compartment 16 for data collection and processing, and then transmitted to the deck terminal via a data cable. After the test is completed, the motor drives the ball screw upward within the working stroke of the electric push rod 2, driving the connecting block 17 to move vertically and steadily upward along the guide rail 3, and the probe 5 is removed from the sediment. The switch of the submersible pump 18 is turned on, the pore water in the probe 5 is collected by the water collecting funnel 11 and then pumped to the submersible pump 18 through the copper pipe 10. The three-way valve 19 is automatically opened, and all the pore water is discharged from the test system to prepare for the next test.

[0040] When conducting in-situ testing of pore water chemical parameters on coastal mudflats, the pore water testing device is fixed to the test stand using bolts and nuts through the through-holes in the docking fixture 1. A motor drives the ball screw downward within the working range of the electric push rod 2, driving the connecting block 17 to move vertically and steadily downward along the guide rail 3. Simultaneously, the probe 5 is inserted downward into the sediment. Pore water passes through the rectangular hole in the probe 5, is filtered by the permeable ceramic 12, and is collected within the probe 5. Various pore water chemical parameters are measured using the microelectrode array 13. The obtained signals are transmitted to the electronic compartment 16 for data collection and processing, and then transmitted to the deck terminal via a data cable. After the test is completed, the motor drives the ball screw upward within the working range of the electric push rod 2, driving the connecting block 17 to move vertically and steadily upward along the guide rail 3, and the probe 5 is removed from the sediment. The switch of the submersible pump 18 is turned on, the pore water in the probe 5 is collected by the water collecting funnel 11 and then pumped to the submersible pump 18 through the copper pipe 10. The three-way valve 19 is automatically opened, and all the pore water is discharged from the test system to prepare for the next test.

[0041] The embodiments described above relate only to preferred embodiments of the present invention and are not intended to limit the concept and scope of the present invention. Any changes and improvements made to the technical solutions of the present invention by persons skilled in the art without departing from the design concept of the present invention are intended to fall within the scope of protection of the present invention. The scope of protection of the present invention is defined by the appended claims and any equivalents thereof.

Claims

1. An in-situ test system for sediment pore water chemical parameters, characterized by: It includes a docking fixing frame (1), an electric push rod (2), a guide rail (3), a connecting rod (4), a probe rod (5), a perforated rubber cover (6), a large end cover (7), a microelectrode connector (8), a small end cover (9), a copper tube (10), a water collecting funnel (11), a water-permeable ceramic (12), a microelectrode group (13), a fixing sleeve (14), a flange (15), an electronic compartment (16), a connecting block (17), a submersible pump (18), and a three-way valve (19); Wherein, the electric push rod (2) and the guide rail (3) are respectively mounted on the docking fixing frame (1); one end of the connecting rod (4) is fixedly connected to the electric push rod (2), and the other end is fixedly connected to the connecting block (17); one end of the connecting block (17) is fixedly connected to the electronic compartment (16), and the other end is fixedly connected to the electric push rod (2); one end of the large end cover (7) is mounted on the electronic compartment (16), and the other end is connected to the flange (15); one end of the small end cover (9) is mounted on the flange (15), and the other end is connected to the fixed sleeve (14); the microelectrode connector (8) is fixed on the small end cover (9), the microelectrode group (13) is mounted on the microelectrode connector (8), and the data wire is led out through the microelectrode connector (8), and introduced into the electronic compartment (16) through the perforated rubber cover (6); The top of the probe rod (5) is fixedly mounted on the small end cap (9). The probe rod (5) is cylindrical with a hollow cavity inside. The microelectrode group (13) penetrates into the inside of the probe rod (5). The wall of the probe rod (5) is provided with a plurality of holes. The bottom end is a pointed cone, which is convenient for penetrating marine sediments. The permeable ceramic (12) is placed on the inner side of the probe rod (5) for in-situ passive collection of sediment pore water samples. The fixed sleeve (14) is pressed into the probe rod (5) to press the permeable ceramic (12) placed on the inner wall of the probe rod (5). One end of the copper tube (10) is connected to the water collecting funnel (11), and is led out through the small end cap (9) via the flange (15) to connect to the lower end of the submersible pump. The submersible pump (18) is mounted on the docking fixing frame (1), one end of which is connected to the copper tube (10) and the other end is connected to the three-way valve (19). The water collecting funnel (11) is designed as a Klein bottle style, the bottom opening of the water collecting funnel (11) is connected to one end of the copper tube (10), and the side wall opening of the water collecting funnel (11) is connected to the other end of the copper tube (10), so as to ensure that the sample is completely replaced; The submersible pump (18) is connected to the three-way valve (19). When the pore water sample test is completed, the submersible pump (18) is turned on, the pore water in the probe rod (5) is pumped into the submersible pump (18), and the three-way valve (19) automatically opens to discharge the pore water.

2. The in-situ sediment pore water chemical parameter testing system according to claim 1, characterized in that: The docking fixing frame (1) has four through holes at the upper and lower ends of the panel, and is fixed to the test bracket or the seabed-based large underwater in-situ test system by bolts and nuts.

3. The sediment pore water chemical parameter in-situ testing system according to claim 1, characterized in that: When the electric push rod (2) is driven by the motor to move the ball screw upward or downward within the working stroke, it drives the connecting block (17) to move upward or downward stably along the guide rail (3) in the vertical direction.

4. The sediment pore water chemical parameter in-situ testing system according to claim 1, characterized in that: The probe rod (5) is provided with a plurality of neatly arranged rectangular holes. When the probe rod (5) enters the sediment, pore water passes through the rectangular holes on the wall of the probe rod (5) and is passively collected into the cavity of the probe rod (5) through the permeable ceramic (12).

5. The sediment pore water chemical parameter in-situ testing system according to claim 1, characterized in that: The microelectrode group (13) is a variety of pH, Ag / AgCl, Ag / Ag2S, Eh, dissolved oxygen, sulfate, and carbonate electrochemical microelectrodes, which are fixed on the microelectrode connector (8) by welding and are used to detect multiple chemical parameters of marine sediment pore water.

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