An experimental apparatus and control method for simulating the physicochemical environmental parameters of a submarine cold seep.

Abstract

An experimental apparatus and control method for simulating the physicochemical environmental parameters of submarine cold seeps include a cold seep chamber system, a background concentration control module, a water-air circulation purification module, a methane medium concentration adjustment module, a physicochemical environmental parameter monitoring module, homogenizing stirring equipment, and a temperature control system. This method simulates the most basic conditions of a submarine cold seep ecosystem by artificially recreating realistic physicochemical environmental conditions of the cold seep area. The cold seep chamber system establishes the simulated space; the background concentration control module controls the concentrations of oxygen, carbon dioxide, etc., within the chamber; the water-air circulation purification module simulates the self-purification capacity of seawater, purifying various waste materials within the chamber; and the methane medium concentration adjustment module enables the controlled injection of methane within the chamber, thus simulating slow, medium, and fast cold seeps. Furthermore, the physicochemical parameters are monitored throughout the process, achieving controllable process control.

Description

Technical Field

[0001] This invention relates to the field of marine engineering technology, and in particular to an experimental apparatus and control method for simulating the physicochemical environmental parameters of seabed cold seeps. Background Technology

[0002] Creating a fully enclosed ecological environment for life science research is a technical challenge. Through continuous and in-depth marine scientific exploration, humans have discovered a self-contained, independent ecosystem on the seabed: the cold seep ecosystem. Its key characteristics are that it is an ecosystem independent of the largest ecosystem on Earth based on photosynthesis; it is of moderate size, and its food chain is not complex, making it suitable for constructing an artificially recreated, fully enclosed cold seep ecological environment under terrestrial conditions.

[0003] The most basic condition for simulating the submarine cold seep ecosystem is to artificially recreate realistic physicochemical environmental conditions of the cold seep area. Based on submarine time monitoring data, the medium concentration indicators of the submarine cold seep area are determined as follows: the background methane concentration in the water is 5 nmol / L, the methane concentration in the area near the cold seep vent and near the sediment is about 10 μmol / L, the methane flux from the cold seep vent varies greatly, and the DIC concentration in the seawater environment of the cold seep area is 3000 μmol / L, with a small amount of hydrogen sulfide dissolved nearby.

[0004] Currently, there is no existing technology that can simulate the concentration requirements of the aforementioned submarine cold seep areas. Summary of the Invention

[0005] To address the shortcomings of existing production technologies, the applicant provides an experimental device and control method for simulating the physicochemical environmental parameters of seabed cold seeps. This allows for the establishment of a stable and realistic seabed cold seep ecological cultivation environment within the cold seep chamber through a complex process control. By faithfully transferring microorganisms and macroorganisms from the seabed cold seep area into the cold seep chamber, a natural development and evolution process can be established, and related scientific experimental research can be conducted.

[0006] The technical solution adopted in this invention is as follows:

[0007] An experimental device for simulating the physicochemical environmental parameters of a cold seep on the seabed includes a cold seep chamber system. The cold seep chamber system is equipped with a basic background concentration control module, a water-air circulation and purification module, a methane medium concentration adjustment module, and a physicochemical environmental parameter monitoring module connected in parallel in sequence. The cold seep chamber system is also connected to a homogenizing stirring device and a temperature control system.

[0008] The structure of the cold seep chamber system is as follows: it includes a cold seep chamber structure, a simulated water body is set inside the cold seep chamber structure, sediment is below the cold seep chamber structure, a diversion plate is set at the bottom of the sediment, a fissure channel is arranged at the center of the sediment, and an aeration head is arranged at the top of the fissure channel.

[0009] The basic background concentration control module has the following structure: an oxygen aqueous solution injection port and a carbon dioxide aqueous solution injection port are set on the upper side wall of the cold spring chamber structure. The oxygen aqueous solution injection port is connected in series with a No. 1 water injection pump, a filter, an oxygen aeration water tank and an oxygen source through a pipeline. An oxygen aeration membrane is installed in the oxygen aeration water tank. The carbon dioxide aqueous solution injection port is connected in series with a No. 1 water injection pump, a filter, a carbon dioxide aeration water tank and a carbon dioxide source through a pipeline. A carbon dioxide aeration membrane is installed in the carbon dioxide aeration water tank.

[0010] The structure of the water-air circulation purification module is as follows: a circulating water outlet and a pH salinity aqueous solution injection port are respectively provided on the upper and lower side walls of the cold spring chamber structure. The circulating water outlet is connected in series with a pressure reducing tank, a bag filter tank, a security filter tank and a degassing membrane assembly through pipelines. The bottom of the degassing membrane assembly is connected to a vacuum pump. The vacuum pump is connected to the pH salinity aqueous solution injection port through a high-pressure pump. The upper part of the degassing membrane assembly is connected to an intermediate water tank through a sampling valve. The intermediate water tank is connected to both the vacuum pump and the high-pressure pump. The intermediate water tank is also connected to a pH salinity adjustment component. The pressure reducing tank is also connected to a nitrogen dilution and emission end through a pressure reducing tank exhaust pipe.

[0011] The structure of the methane medium concentration regulation module is as follows: A methane aqueous solution injection port is set at the bottom of the cold spring chamber structure. The methane aqueous solution injection port is connected to the distribution plate. The methane aqueous solution injection port is connected in series with a No. 2 water injection pump, a water tank and a gas source through pipelines. An aeration device is set in the water tank. The methane aqueous solution injection port branches into a methane gas injection port. The methane gas injection port is connected in series with a flow meter and a gas booster through pipelines. The gas booster output has two parallel management lines. One line is connected in series with an inlet pressure regulating valve, an inlet filter and a gas source. The other line is connected in series with a drive gas flow regulating valve and compressed air.

[0012] The structure of the physical and chemical environmental parameter monitoring module is as follows: Raman probe, H2S and pH sensor, CH4 sensor and CTD and DO sensor are installed inside the cold seep chamber structure. DIC detector and Raman spectrometer are installed outside the cold seep chamber structure. DIC detector, Raman spectrometer, Raman probe and each sensor are connected to the cold seep environmental monitoring system.

[0013] Its further technical solution lies in:

[0014] The cold spring chamber structure is a large-scale high-pressure container with a water level of 15m inside.

[0015] The top of the cold spring chamber structure is equipped with a safety valve and a pressure sensor.

[0016] The cold spring chamber structure is designed to be corrosion resistant, consisting of, from the outside in, the cold spring chamber substrate, a corrosion-resistant alloy weld overlay layer, and an alumina ceramic coating.

[0017] The distribution plate is designed as a cross-shaped distribution channel with seepage holes.

[0018] The temperature control system regulates the temperature of the water in the cold spring chamber and keeps it stable within the range of 2 to 4°C.

[0019] A control method for an experimental apparatus simulating the physicochemical environmental parameters of a submarine cold seep.

[0020] S1. Preparation Phase:

[0021] In the empty state, the diversion plate, fissure channel, and aeration head are pre-arranged in the cold seep chamber structure, the sediment is arranged in the cold seep chamber structure, and an air injection cavity is reserved.

[0022] S2. Water injection pressurization and temperature control:

[0023] High-pressure pumps are used to draw seawater from the intermediate water tank and inject it into the cold spring chamber structure to increase the pressure inside the chamber to 20MPa. At the same time, the temperature control system is activated to adjust and control the temperature of the cold spring chamber system, so that the temperature of the cold spring chamber structure and the simulated water body is reduced to 2-4℃ and stabilized within this temperature range.

[0024] S3. Initialization of background concentration of medium in cold seep chamber:

[0025] Oxygen is introduced into the oxygen aeration membrane, where it breaks up oxygen bubbles for rapid dissolution. An oxygen-water solution of a specified concentration is prepared in the oxygen aeration tank, filtered, and then injected into the cold seep chamber system through the oxygen-water solution injection port at the top by the No. 1 water injection pump. Similarly, carbon dioxide is introduced and injected using the same process. To simulate the actual diffusion state of oxygen and carbon dioxide, the injection port is located at the top of the cold seep chamber system, which can realistically simulate the diffusion direction of oxygen and dissolved carbon in the actual ocean.

[0026] S4, Water-Air Circulation Purification Simulation:

[0027] A circulating water outlet is installed at the top of the cold spring tank system. By controlling the circulation flow, seawater containing high concentrations of waste is transported to the depressurization tank, where it is depressurized to below 1 MPa. During the depressurization process, dissolved gas may be released. Therefore, the released gas can be discharged to the nitrogen dilution discharge end through the depressurization tank exhaust pipe for post-treatment. The seawater in the depressurization tank continues to be fully filtered through bag filter tanks and security filter tanks before entering the degassing membrane module for multi-stage degassing. In the degassing membrane, a vacuum pump is used to create a suction negative pressure, which removes and discharges various dissolved wastes from the seawater. The concentration of various gaseous media in the degassing seawater can be controlled below 10 ppb. The purified seawater flows into the intermediate water tank for recycling.

[0028] S5, Cold Fountain Feather Simulation:

[0029] Methane gas is injected into the aeration device through a methane gas source, forming a methane solution of a certain concentration in the water tank. The methane solution is then injected into the distribution plate in the cold spring chamber system through the methane water inlet using a water pump. After distribution, it is evenly diffused into the aeration cavity. The concentration difference drives the methane solution to permeate through the sediment, forming a layer of high-concentration methane solution on the surface of the sediment, thereby providing energy supply for the cold spring ecosystem.

[0030] S6. Simulated cold seep physicochemical environment monitoring:

[0031] Throughout the entire process of simulating the physicochemical environment of a cold seep area on the seabed, a Raman spectrometer was activated to measure the concentration of various media within the chamber using Raman probes. Simultaneously, H2S, pH, CH4, CTD, and DO sensors were activated to monitor the concentration, temperature, and pressure field of the media within the chamber in real time. Meanwhile, the media within the chamber were periodically sampled, and the dissolved carbon concentration was detected using a DIC detector. Based on the monitoring results, the control of various process parameters in the five steps was guided in real time to ensure that the physicochemical parameters within the chamber remained stable within a reasonable range.

[0032] In S3, if it is necessary to accelerate the initialization process during the background concentration initialization process, the concentration of the medium in the chamber can be accelerated and made uniform by starting the homogenizing stirring equipment.

[0033] In S4, considering that the purification process will affect the actual pH and salinity of the seawater, the pH and salinity adjustment components are used to readjust the seawater in the intermediate tank to meet the reinjection requirements. The high-pressure pump is used to reinject the purified seawater to ensure that the pressure of the cold spring chamber system is stable and the pressure fluctuation is no more than 2.5%.

[0034] This involves establishing an open circulation system that artificially simulates the powerful self-purification capabilities of seawater.

[0035] In S5, for the medium-speed cold seep simulation method, a methane gas source is used. The gas is pressurized by a gas booster, and the gas flow rate is monitored by a flow meter. The gas is injected into the distribution plate through the methane gas injection port and further diffused into the gas injection cavity. It continuously permeates through the sediment and forms a small-scale plume on the sediment surface. This mode is the most common mode of cold seep ecosystem.

[0036] The rapid cold seep simulation method mainly simulates the violent methane eruption caused by a large-scale methane overflow after the formation becomes unstable.

[0037] The gas is pressurized by a gas booster, and the gas flow rate is monitored by a flow meter. The gas is then injected into the fissure channel through the methane injection port, where the aeration head breaks up the methane gas, resulting in a large-scale methane eruption and establishing a rapid cold spring state.

[0038] The beneficial effects of this invention are as follows:

[0039] This invention features a compact and rational structure, and is easy to operate. Through the coordinated operation of the cold seep chamber system and its various modules, an open-loop circulation system is constructed to artificially simulate the powerful self-purification capacity of seawater, thereby purifying various waste materials within the simulated cold seep chamber and maintaining environmental stability. A methane injection system is also established to simulate methane aqueous solutions, methane gas leakage, and large-scale methane eruptions, thus simulating the physical states of cold seeps, medium-speed cold seeps, and fast-moving cold seeps. Furthermore, a temperature and pressure control system is constructed to stabilize the pressure and temperature fields within the simulated experimental chamber, maintaining the pressure field at the target water depth and the temperature field within the range of 2-4°C.

[0040] This invention can simulate the stable maintenance of physicochemical parameters in a cold seep area on the seabed. It is an experimental device that can realize the artificial simulation of seawater self-purification ability and the stable control of the concentration of various media. It can obtain sediment, water samples, microorganisms and macroorganisms through in-situ authentic sampling on the seabed to carry out long-term experimental research on the simulated cold seep ecological environment.

[0041] This invention relates to a high-pressure simulation device that can artificially recreate the physicochemical environmental parameters of cold seep areas on land. It can construct a realistic living environment for microorganisms and macroorganisms in the cold seep areas of the seabed, enabling them to grow, develop and reproduce in such an artificial environment. This helps scientists to conduct scientific experiments on life, chemistry and geology based on the specific characteristics of the cold seep areas of the seabed, and belongs to the field of special experimental devices. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the structure of the present invention.

[0043] Figure 2 This is a schematic diagram of the cold spring chamber system of the present invention.

[0044] Figure 3 This is a schematic diagram of the anti-corrosion structure of the cold spring chamber of the present invention.

[0045] Figure 4 This is a schematic diagram of the structure of the flow divider of the present invention.

[0046] Figure 5 This is a schematic diagram of the basic background concentration control module of the present invention.

[0047] Figure 6 for Figure 5 A partial view.

[0048] Figure 7 This is a schematic diagram of the structure of the water-air circulation purification module of the present invention.

[0049] Figure 8 This is a schematic diagram of the methane medium concentration adjustment module of the present invention.

[0050] Figure 9 for Figure 8 A partial view.

[0051] Figure 10 This is a schematic diagram of the physical environment parameter monitoring module of the present invention.

[0052] Figure 11 for Figure 10 A partial view.

[0053] The system includes: 1. Cold spring chamber system; 2. Basic background concentration control module; 3. Water and air circulation purification module; 4. Methane medium concentration adjustment module; 5. Physicochemical environmental parameter monitoring module; 6. Homogenization stirring equipment; 7. Temperature control system.

[0054] 101. Cold seep chamber structure; 102. Simulated water body; 103. Sediments; 104. Air injection cavity; 105. Diverter plate; 106. Fissure channel; 107. Aeration head; 108. Safety valve; 109. Pressure sensor;

[0055] 10501, Diversion channel; 10502, Seepage hole;

[0056] 201. Oxygen source; 202. Oxygen aeration tank; 203. Oxygen aeration membrane; 204. Filter; 205. No. 1 water injection pump; 206. Oxygen aqueous solution inlet; 207. Carbon dioxide source; 208. Carbon dioxide aeration tank; 209. Carbon dioxide aeration membrane; 210. Carbon dioxide aqueous solution inlet;

[0057] 301. Intermediate water tank; 302. pH and salinity adjustment assembly; 303. Nitrogen dilution and discharge end; 304. High-pressure pump; 305. pH and salinity aqueous solution inlet; 306. Sampling valve; 307. Degassing membrane assembly; 308. Security filter tank; 309. Bag filter tank; 310. Pressure reducing tank; 311. Pressure reducing tank exhaust pipe; 312. Air inlet channel; 313. Circulating water outlet;

[0058] 401. Gas source; 402. Compressed air; 403. Inlet filter; 404. Inlet pressure regulating valve; 405. Drive gas flow regulating valve; 406. Gas booster; 407. Flow meter; 408. Methane gas injection port; 409. Water tank; 410. Aeration device; 411. Second water injection pump; 412. Methane aqueous solution injection port;

[0059] 501. Cold seep environmental monitoring system; 502. Raman spectrometer; 503. DIC detector; 504. Raman probe; 505. H2S and pH sensor; 506. CH4 sensor; 507. CTD and DO sensor. Detailed Implementation

[0060] The specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0061] The specific structure and function of the experimental apparatus for simulating the physicochemical environmental parameters of a submarine cold seep according to the present invention are as follows:

[0062] It mainly includes a cold spring chamber system 1, a basic background concentration control module 2, a water and air circulation purification module 3, a methane medium concentration adjustment module 4, a physicochemical environmental parameter monitoring module 5, a homogenization stirring device 6, and a temperature control system 7.

[0063] The cold seep chamber system 1 consists of a cold seep chamber structure 101, a simulated water body 102, sediment 103, an air injection cavity 104, a diversion plate 105, a fissure channel 106, an aeration head 107, a safety valve 108, and a pressure sensor 109.

[0064] The cold seep chamber structure 101 is a large-scale high-pressure container with an internal water level of 15m and a bottom sediment area of ​​20m². 2The cold seep chamber structure 101 can withstand an internal pressure of 20 MPa, simulating the pressure environment at a depth of 2000 m on the seabed. Simultaneously, a temperature control system 7 is used to regulate and control the water temperature within the cold seep chamber, maintaining it within the range of 2–4 °C. Samples of sediment 103, obtained in situ from the seabed cold seep area, were artificially transported into the cold seep chamber structure 101, constructing a sediment layer consistent with the actual cold seep area. However, a certain volume of aeration cavity 104 needs to be constructed at the bottom of the sediment 103 to allow the injection of methane and other media, simulating the upward seepage and migration of deep seabed media. A fracture channel 106 is arranged at the center of the sediment 103 to simulate geological fissures that may exist in the actual sediment layer 103, thus establishing a low-resistance media seepage channel to simulate methane gas eruption. An aerator 107 is arranged at the top of the fracture channel 106 to break up the methane gas, more realistically simulating the plume formed by a methane eruption. The top of the cold spring structure is equipped with a safety valve 108 and a pressure sensor 109, which can monitor the pressure inside the chamber in real time to prevent overpressure.

[0065] Given the unique environmental characteristics of the cold seep area, the environment inside the cold seep chamber is highly corrosive, primarily due to the combined effects of seawater, pressure, and hydrogen sulfide. To ensure the structural integrity of the cold seep chamber (101), a corrosion-resistant alloy overlay is welded onto the inner surface of the chamber substrate, establishing an anti-corrosion structure capable of withstanding the highly corrosive environment inside. Simultaneously, to maintain the realism of the internal environment and further reduce the release of metal ions from the anti-corrosion layer into the chamber, an alumina ceramic coating is thermally sprayed onto the inner surface of the overlay. This coating, approximately tens of micrometers thick, creates an insulating layer that effectively prevents the release of metal ions, ensuring controllable concentrations of various media within the chamber.

[0066] To further improve the uniformity and stability of the medium permeating from the gas injection cavity 104 to the sediment 103, a diversion plate 105 is arranged at the bottom of the gas injection cavity 104. The diversion plate 105 has permeation holes 10502 arranged in four or more directions, which can divert the injected methane medium to achieve uniform diffusion into the gas injection cavity 104, thereby achieving uniform permeation.

[0067] The basic background concentration control module is primarily designed to establish a fundamental background concentration environment within the cold seep chamber system 1, mainly addressing the control of oxygen and dissolved carbon concentrations in the water. Considering that oxygen and dissolved carbon in seawater primarily originate from the atmosphere, the injection port should be located at the top of the chamber to simulate the top-down transport process of oxygen, carbon dioxide, and other media, better reflecting the actual characteristics of the seabed. Specifically, it includes an air source, an aeration tank, an aeration membrane, a filter, and an injection pump. By introducing an artificial air source and installing the aeration membrane inside the aeration tank, the dissolution rate of the gas in the water is accelerated. The injection pump then injects seawater containing dissolved oxygen and carbon dioxide into the cold seep chamber, and the concentration of the media within the chamber is monitored in real time. If necessary, the homogenizing and stirring device 6 can be activated to accelerate the homogenization of the media concentration within the chamber, thereby achieving the initial establishment of the background concentration.

[0068] The water-air circulation purification module 3 is one of the important modules in this experimental setup. Its main function is to artificially simulate the powerful self-purification capacity of seawater. Cold seep ecosystems are characterized by the continuous eruption of methane media from the seabed and the biological waste generated during the ecosystem's continuous reproduction process. Ocean currents can quickly transfer and dilute excess waste media, ensuring a relatively stable physicochemical environment near the cold seep area. The cold seep chamber structure 101 is a very limited space, making it impossible to achieve such a powerful self-purification capacity. Therefore, a water-air circulation purification module 3 was established to address the purification problem of various excess media during the cold seep ecosystem inversion process.

[0069] Specifically, the system includes an intermediate water tank 301, a pH and salinity adjustment component 302, a nitrogen dilution system, a high-pressure pump 304, a pH and salinity aqueous solution inlet 305, a sampling valve 306, a degassing membrane component 307, a filter, a nitrogen inlet channel, a pressure reducing tank 310, a pressure reducing tank exhaust pipe 311, and a circulating water outlet 313. These components, together with the cold seep chamber structure 101, form a complete open-loop circulation system. Driven by pressure within the cold seep chamber, a high-concentration medium of seawater with a controllable flow rate is discharged from the top and enters the pressure reducing tank 310 for degassing. During degassing, some gases with solubility exceeding the saturation concentration require venting. To ensure the discharged gases do not pose a risk of combustion or explosion, they are inerted and diluted with nitrogen before further treatment. The seawater solution after degassing in the pressure reducing tank 310 enters the degassing membrane component for further degassing. After this treatment, the gas concentration can be controlled below 10 ppb, completely lower than the background concentration of seawater, and is considered purified seawater. During the degassing process, sampling valve 306 can be used to sample and calibrate the concentration of various media in the purified seawater. The purified seawater enters the intermediate water tank 301, where the pH and salinity adjustment component 302 artificially restores them to their original values, ensuring that the pH and salinity of the purified seawater remain consistent with those in the cold seep chamber. Once the usage requirements are met, a high-pressure pump is used to reinject the seawater from the intermediate water tank 301 back into the cold seep chamber. Throughout the entire circulation process, the injection section uses flow rate as the control criterion, while the outlet section uses pressure as the control criterion, achieving an open circulation to ensure that the pressure fluctuation in the cold seep chamber is less than 2.5%.

[0070] The methane medium concentration regulation module 4 is another important module in this experimental setup. Its main function is to artificially control the injection of methane solution or methane gas to induce the formation of slow, medium, and fast cold springs. It also supplies methane medium to the cold spring chamber in real time, providing the established cold spring ecosystem with regenerated nutrients, enabling it to carry out sufficient chemosynthesis within the chamber.

[0071] Specifically, the system includes a gas source, a gas filter, a pressure regulating valve, a gas booster 406, a flow meter 407, a methane dissolving tank, an aeration device 410, and a water injection pump. A complete methane medium injection channel is established using the distribution plate 105, the air injection cavity 104, the fissure channel 106, and the aeration head 107 within the cold spring chamber system 1. The methane solution is primarily prepared using the methane dissolving tank and its internal aeration device 410. The water injection pump injects the solution into the distribution plate 105 within the cold spring chamber, where it diffuses into the air injection cavity 104. Through osmosis, the solution gradually penetrates to the surface of the sediment 103, thus simulating a slow cold spring. The gas booster 406 draws in methane gas, directly injecting it into the distribution plate 105. Utilizing the upward transport characteristics of the gas, the gas fills the air injection cavity 104 and permeates through the sediment 103, forming a plume on the surface of the sediment 103, which can simulate a medium-speed cold spring. By modifying the methane injection channel into a fissure channel 106, a large-scale plume flow can be simulated, thereby realizing the simulation process of rapid cold seeps.

[0072] The physicochemical environmental parameter monitoring module is primarily responsible for real-time monitoring of various physicochemical parameters within the cold seep chamber system 1 to ensure that the internal environment conforms to the characteristics of the seabed cold seep area, thereby facilitating accurate scientific experimental research. Specifically, it includes various sensors based on photochemical principles, such as Raman probe 504, H2S and pH sensors 505, CH4 sensor 506, CTD and DO sensors 507, DIC detector 503, and Raman spectrometer 502. The real-time status of various physicochemical parameters within the chamber is ultimately calculated by the cold seep environment monitoring system 501.

[0073] Composition of the experimental setup for simulating the physicochemical environmental parameters of submarine cold seeps:

[0074] like Figure 1 The diagram shows the system composition of an experimental apparatus for simulating the physicochemical environmental parameters of a cold seep on the seabed: 1. Cold seep chamber system; 2. Basic background concentration control module; 3. Water and air circulation purification module; 4. Methane medium concentration adjustment module; 5. Physicochemical environmental parameter monitoring module; 6. Homogenizing stirring equipment; 7. Temperature control system.

[0075] like Figure 2 As shown, the components of the cold seep chamber system 1 are: cold seep chamber structure 101, simulated water body 102, sediment 103, air injection cavity 104, diversion plate 105, fissure channel 106, aeration head 107, safety valve 108, and pressure sensor 109.

[0076] like Figure 3The diagram shows the corrosion protection structure of the cold seep chamber. Considering the presence of seawater, pressure, and hydrogen sulfide within the chamber, a special design was implemented for corrosion protection. From the outside in, the structure consists of the cold seep chamber substrate 10101, a corrosion-resistant alloy weld overlay layer 10102, and an alumina ceramic coating 10103. Specific functions: Given the unique corrosive environment of the cold seep area, to ensure the cold seep chamber substrate 101 remains undamaged, a corrosion-resistant alloy 10102 is welded onto its inner surface. Its main function is as a basic corrosion protection layer, serving as the final protective barrier for the cold seep chamber structure. With a certain effective thickness, it ensures that the chamber structure does not come into direct contact with corrosive media, preventing damage and destruction to the structure. Because cold seep ecosystems are relatively fragile, it is extremely difficult to construct the physical and chemical environment of a cold seep area. In order to control the release of metal ions from the cabin structure into the water and thus affect the realistic simulation of the cold seep ecosystem, an alumina ceramic coating 10103 is sprayed onto the surface of the corrosion-resistant alloy weld overlay 10102 using a thermal spraying method to form an isolation layer, effectively controlling the release rate of various metal ions and ensuring the realism of the cabin environment.

[0077] like Figure 4 The diagram shows the detailed components of the distribution plate 105: distribution channel 10501 and seepage hole 10502.

[0078] like Figure 5 As shown, the basic background concentration control module 2 consists of: oxygen source 201, oxygen aeration tank 202, oxygen aeration membrane 203, filter 204, No. 1 water injection pump 205, oxygen aqueous solution injection port 206, carbon dioxide source 207, carbon dioxide aeration tank 208, carbon dioxide aeration membrane 209, and carbon dioxide aqueous solution injection port 210.

[0079] like Figure 6 As shown, the water-air circulation purification module 3 consists of: an intermediate water tank 301, a pH and salinity adjustment component 302, a nitrogen dilution and discharge end 303, a high-pressure pump 304, a pH and salinity aqueous solution inlet 305, a sampling valve 306, a degassing membrane component 307, a security filter tank 308, a bag filter tank 309, a pressure reducing tank 310, a pressure reducing tank exhaust pipe 311, an air inlet channel 312, and a circulating water outlet 313.

[0080] like Figure 7 The diagram shows the components of the methane medium concentration adjustment module 4: gas source 401, compressed air 402, air inlet filter 403, air inlet pressure regulating valve 404, drive gas flow regulating valve 405, gas booster 406, flow meter 407, methane gas injection port 408, water tank 409, aeration device 410, second water injection pump 411, and methane aqueous solution injection port 412.

[0081] like Figure 8As shown, the physicochemical environmental parameter monitoring module 5 consists of: cold seep environment monitoring system 501, Raman spectrometer 502, DIC detector 503, Raman probe 504, H2S and pH sensor 505, CH4 sensor 506, and CTD and DO sensor 507.

[0082] For the experimental setup designed to simulate the physicochemical environmental parameters of the deep-sea cold seep, a reasonable control method is designed to more accurately establish a set of artificially reconstructed physicochemical environmental conditions of the deep-sea cold seep area for related experimental research.

[0083] The specific steps are as follows:

[0084] Step 1: Preparation Stage

[0085] In the empty chamber state, the diversion plate 105, fissure channel 106, and aeration head 107 are pre-arranged in the cold seep chamber structure 101. The sediment 103 is arranged in the cold seep chamber structure 101, and an air injection cavity 104 is reserved.

[0086] Step 2: Water Injection, Pressurization, and Temperature Control

[0087] High-pressure pump 304 draws seawater from intermediate water tank 301 and injects it into cold spring chamber structure 101 to increase the pressure inside the chamber to 20MPa. At the same time, temperature control system 7 is activated to adjust and control the temperature of cold spring chamber system 1, so that the temperature of cold spring chamber structure 101 and simulated water body 102 is reduced to 2-4℃ and stabilized within this temperature range.

[0088] Step 3: Initialize the background concentration of the medium in the cold seep chamber:

[0089] Oxygen source 201 is introduced and injected into oxygen aeration membrane 203. The oxygen aeration membrane 203 breaks up oxygen bubbles for rapid dissolution. An oxygen-water solution of a specified concentration is prepared in oxygen aeration tank 202, filtered by filter 204, and then injected into the cold seep chamber system 1 through oxygen-water solution injection port 206 at the top by a water pump. Similarly, carbon dioxide source 207 is introduced, and carbon dioxide is injected using the same process. To simulate the actual diffusion state of oxygen and carbon dioxide, the injection port is located at the top of the cold seep chamber system 1, realistically simulating the diffusion direction of oxygen and dissolved carbon in the actual ocean. During background concentration initialization, if it is necessary to accelerate the initialization process, the homogenizing stirring device 6 can be activated to accelerate and homogenize the concentration of the medium inside the chamber.

[0090] Step 4: Simulation of water and air circulation purification:

[0091] A circulating water outlet 313 is installed at the top of the cold spring chamber system 1. By controlling the circulation flow, seawater containing high concentrations of waste is transported to the pressure reducing tank 310, where the pressure is reduced to below 1 MPa. During the pressure reduction process, dissolved gas may be released. Therefore, the released gas can be discharged to the nitrogen dilution discharge end 303 through the pressure reducing tank exhaust pipe 311 for post-treatment. The seawater in the pressure reducing tank 310 continues to be fully filtered through the bag filter tank 309 and the security filter tank 308 before entering the degassing membrane module 307 for multi-stage degassing. In the degassing membrane 307, a vacuum pump is used to create a suction negative pressure, thereby removing and discharging various dissolved wastes from the seawater. The concentration of various gaseous media in the degassed seawater can be controlled below 10 ppb. The purified seawater flows into the intermediate water tank 301 for recycling. Considering that the purification process may affect the actual pH and salinity of the seawater, the pH and salinity adjustment component 302 is used to readjust the seawater in the intermediate water tank 301 to meet the reinjection requirements. By using high-pressure pump 304 to reinject purified seawater, the pressure of the cold spring chamber system 1 is kept stable, with pressure fluctuations not exceeding 2.5%. Thus, an open circulation system that artificially simulates the powerful self-purification ability of seawater is established.

[0092] Step 5: Simulation of Cold Seep Flow:

[0093] Simulating cold seep plumes is crucial for reconstructing the physicochemical environmental parameters of cold seeps. Based on different methane emission rates, cold seeps can be categorized into slow-speed, medium-speed, and fast-speed cold seeps.

[0094] For the slow cold spring simulation method, methane gas is injected into the aeration device 410 through a methane gas source, forming a methane solution of a certain concentration in the water tank 409. The methane aqueous solution is then injected into the diversion plate 105 in the cold spring chamber system 1 through the methane aqueous solution injection port 412 using the second water injection pump 411. After diversion, it is evenly diffused into the aeration cavity 104. The concentration difference drives the methane aqueous solution to permeate through the sediment 103, forming a layer of high-concentration methane solution on the surface of the sediment 103, thereby providing energy supply for the cold spring ecosystem.

[0095] For the medium-speed cold seep simulation method, a methane gas source is used, which is pressurized by a gas booster 406. The gas flow rate is monitored by a flow meter 407. The gas is injected into the distribution plate 105 through the methane gas injection port 408 and further diffused into the gas injection cavity 104. It continuously permeates through the sediment 103 and forms a small-scale plume on the surface of the sediment 103. This mode is the most common mode of cold seep ecosystem.

[0096] The rapid cold seep simulation method primarily simulates the violent methane eruption caused by a large-scale methane spill after formation instability. Methane gas is supplied by source 401, pressurized by gas booster 406, and its flow rate is monitored by flow meter 407. The gas is then injected into fracture channel 106 through methane injection port 408, where aeration head 107 breaks up the methane gas, resulting in a large-scale methane eruption and establishing a rapid cold seep state.

[0097] The above-described culture model can establish a culture environment that simulates the physicochemical parameters of a submarine cold seep area, thereby achieving the goal of cultivating microorganisms and macroorganisms in the submarine cold seep area.

[0098] Step Six: Simulated Cold Seep Physicochemical Environment Monitoring:

[0099] Throughout the simulation of the physicochemical environment of a cold seep area on the seabed, Raman spectrometer 502 was activated, and Raman probe 504 was used to measure the concentrations of various media within the chamber. Simultaneously, H2S and pH sensors 505, CH4 sensor 506, and CTD and DO sensors 507 were activated to monitor the concentration, temperature, and pressure field of the media within the chamber in real time. Meanwhile, the media within the chamber were periodically sampled, and dissolved carbon concentration was detected using DIC detector 503. Based on the monitoring results, the control of various process parameters in the five steps was guided in real time to ensure that the physicochemical parameters within the chamber remained stable within a reasonable range.

[0100] The above description is an explanation of the present invention and not a limitation thereof. The scope of the present invention is defined by the claims. Within the scope of protection of the present invention, any form of modification may be made.

Claims

1. An experimental apparatus for simulating the physicochemical environmental parameters of a submarine cold seep, characterized in that: The system includes a cold spring chamber system (1), on which a basic background concentration control module (2), a water and air circulation purification module (3), a methane medium concentration adjustment module (4) and a physicochemical environmental parameter monitoring module (5) are connected in parallel in sequence. The cold spring chamber system (1) is also connected to a homogenization stirring device (6) and a temperature control system (7). The structure of the cold seep chamber system (1) is as follows: it includes a cold seep chamber structure (101), a simulated water body (102) is set inside the cold seep chamber structure (101), sediment (103) is below the cold seep chamber structure (101), a diversion plate (105) is set at the bottom of the sediment (103), a fissure channel (106) is arranged at the center of the sediment (103), and an aeration head (107) is arranged at the top of the fissure channel (106). The basic background concentration control module (2) has the following structure: an oxygen water solution injection port (206) and a carbon dioxide water solution injection port (210) are provided on the upper side wall of the cold spring chamber structure (101). The oxygen water solution injection port (206) is connected in series with a No. 1 water injection pump (205), a filter (204), an oxygen aeration tank (202) and an oxygen source (201) through a pipeline. An oxygen aeration membrane (203) is installed in the oxygen aeration tank (202). The carbon dioxide water solution injection port (210) is connected in series with a No. 1 water injection pump (205), a filter (204), a carbon dioxide aeration tank (208) and a carbon dioxide source (207) through a pipeline. A carbon dioxide aeration membrane (209) is installed in the carbon dioxide aeration tank (208). The structure of the water-air circulation purification module (3) is as follows: a circulating water outlet (313) and a pH salinity aqueous solution inlet (305) are respectively provided on the upper and lower side walls of the cold spring chamber structure (101). The circulating water outlet (313) is connected in series with a pressure reducing tank (310), a bag filter tank (309), a security filter tank (308) and a degassing membrane assembly (307) through a pipeline. The bottom of the degassing membrane assembly (307) is connected to a vacuum pump. The vacuum pump is connected to the pH salinity aqueous solution inlet (305) through a high-pressure pump (304). The upper part of the degassing membrane assembly (307) is connected to an intermediate water tank (301) through a sampling valve (306). The intermediate water tank (301) is connected to both the vacuum pump and the high-pressure pump (304). The intermediate water tank (301) is also connected to a pH salinity adjustment assembly (302). The pressure reducing tank (310) is also connected to a nitrogen dilution discharge end (303) through a pressure reducing tank exhaust pipe (311). The structure of the methane medium concentration regulating module (4) is as follows: a methane aqueous solution injection port (412) is provided at the bottom of the cold spring chamber structure (101). The methane aqueous solution injection port (412) is connected to the distribution plate (105). The methane aqueous solution injection port (412) is connected in series with the No. 2 water injection pump (411), water tank (409) and gas source (401) through pipelines. An aeration device (410) is provided in the water tank (409). The methane aqueous solution injection port (412) branches into a methane gas injection port (408). The methane gas injection port (408) is connected in series with a flow meter (407) and a gas booster (406) through pipelines. The gas booster (406) outputs two parallel pipelines. One is connected in series with an inlet pressure regulating valve (404), an inlet filter (403) and a gas source (401). The other is connected in series with a drive gas flow regulating valve (405) and compressed air (402). The structure of the physical and chemical environmental parameter monitoring module (5) is as follows: a Raman probe (504), an H2S and pH sensor (505), a CH4 sensor (506), and a CTD and DO sensor (507) are installed inside the cold seep chamber structure (101). A DIC detector (503) and a Raman spectrometer (502) are installed outside the cold seep chamber structure (101). The DIC detector (503), the Raman spectrometer (502), the Raman probe (504), and each sensor are connected to the cold seep environmental monitoring system (501).

2. The experimental apparatus for simulating the physicochemical environmental parameters of a submarine cold seep as described in claim 1, characterized in that: The cold spring chamber structure (101) is a large-scale high-pressure container with a water level of 15m inside.

3. The experimental apparatus for simulating the physicochemical environmental parameters of a submarine cold seep as described in claim 1, characterized in that: A safety valve (108) and a pressure sensor (109) are installed on the top of the cold spring chamber structure (101).

4. The experimental apparatus for simulating the physicochemical environmental parameters of a submarine cold seep as described in claim 1, characterized in that: The cold spring chamber structure (101) is designed to be corrosion resistant, consisting of a cold spring chamber substrate (10101), a corrosion-resistant alloy weld overlay (10102), and an alumina ceramic coating (10103) from the outside to the inside.

5. The experimental apparatus for simulating the physicochemical environmental parameters of a submarine cold seep as described in claim 1, characterized in that: The diversion plate (105) is configured as a cross-shaped diversion channel (10501), and seepage holes (10502) are opened on the diversion channel (10501).

6. The experimental apparatus for simulating the physicochemical environmental parameters of a submarine cold seep as described in claim 1, characterized in that: The temperature control system (7) regulates the temperature of the water in the cold spring chamber and keeps the temperature stable within the range of 2 to 4°C.

7. A control method for an experimental apparatus for simulating the physicochemical environmental parameters of a submarine cold seep as described in claim 1, characterized in that: The following steps are included: S1. Preparation Phase: In the empty state, the diversion plate (105), fissure channel (106), and aeration head (107) are arranged in advance in the cold seep chamber structure (101), the sediment (103) is arranged in the cold seep chamber structure (101), and an air injection cavity (104) is reserved. S2. Water injection pressurization and temperature control: High-pressure pump (304) is used to draw seawater from intermediate water tank (301) and inject it into cold spring chamber structure (101) to increase the pressure inside the chamber to 20MPa. At the same time, temperature control system (7) is activated to adjust and control the temperature of cold spring chamber system (1) so that the temperature of cold spring chamber structure (101) and simulated water body (102) is reduced to 2~4℃ and stabilized in this temperature range. S3. Initialization of background concentration of medium in cold seep chamber: By introducing an oxygen source (201) and injecting it into the oxygen aeration membrane (203), the oxygen bubbles are broken by the aeration membrane (203) to achieve rapid dissolution. An oxygen water solution of a specified concentration is prepared in the oxygen aeration tank (202). After being filtered by the filter (204), it is injected into the chamber by the first water injection pump (205) through the oxygen water solution injection port (206) at the top of the cold seep chamber system (1). Similarly, a carbon dioxide source (207) is introduced, and the carbon dioxide injection is completed using the same process. In order to simulate the actual diffusion state of oxygen and carbon dioxide media, the injection port is determined to be at the top of the cold seep chamber system (1), which can realistically simulate the diffusion direction of oxygen and dissolved carbon in the actual ocean. S4, Water-Air Circulation Purification Simulation: A circulating water outlet (313) is set at the top of the cold spring chamber system (1). By controlling the circulation flow, seawater containing high concentrations of waste is transported to the pressure reducing tank (310). The pressure is reduced to less than 1 MPa by the pressure reducing tank (310). During the pressure reduction process, there may be dissolved gas precipitation. Therefore, the precipitated gas can be discharged to the nitrogen dilution discharge end (303) through the pressure reducing tank exhaust pipe (311) to complete the gas post-treatment. The seawater in the pressure reducing tank (310) continues to be fully filtered through the bag filter tank (309) and the security filter tank (308) and then enters the degassing membrane module (307) for multi-stage degassing treatment. In the degassing membrane module (307), a vacuum pump is used to form a suction negative pressure to realize the separation and discharge of various dissolved wastes in the seawater. The concentration of various gas media in the degassing seawater can be controlled to less than 10 ppb. The purified seawater flows into the intermediate water tank (301) for recycling. S5, Cold Fountain Feather Simulation: Methane gas is injected into the aeration device (410) through a methane gas source, forming a methane solution of a certain concentration in the water tank (409). The methane aqueous solution is injected into the diversion plate (105) in the cold spring chamber system (1) through the methane water inlet (412) using the water injection pump (411). After diversion, it is evenly diffused into the air injection cavity (104). The concentration difference drives the methane aqueous solution to permeate through the sediment (103), forming a layer of methane solution with a higher concentration on the surface of the sediment (103), thereby providing energy supply for the cold spring ecosystem. S6. Simulated cold seep physicochemical environment monitoring: Throughout the entire process of simulating the physicochemical environment of the cold seep area on the seabed, a Raman spectrometer (502) was activated, and the concentration of various media in the chamber was measured using a Raman probe (504). At the same time, H2S and pH sensors (505), CH4 sensor (506), CTD and DO sensor (507) were activated to monitor the concentration, temperature and pressure field of the media in the chamber in real time. Meanwhile, the media in the chamber were sampled periodically, and the dissolved carbon concentration in the chamber was detected using a DIC detector (503). Based on the above monitoring results, the control of various process parameters in the above five steps was guided in real time to ensure that the physicochemical parameters in the chamber remained stable within a reasonable range.

8. The control method of the experimental apparatus for simulating the physicochemical environmental parameters of a submarine cold seep as described in claim 7, characterized in that: In S3, if it is necessary to accelerate the initialization process during the background concentration initialization process, the concentration of the medium in the chamber can be accelerated and made uniform by starting the homogenizing stirring device (6).

9. The control method of the experimental apparatus for simulating the physicochemical environmental parameters of a submarine cold seep as described in claim 7, characterized in that: In S4, considering that the purification process will affect the actual pH value and salinity of the seawater, the pH value and salinity adjustment component (302) is used to readjust the seawater in the intermediate water tank (301) to meet the reinjection requirements; then the high pressure pump (304) is used to reinject the purified seawater to ensure that the pressure of the cold spring chamber system (1) is stable and the pressure fluctuation is no more than 2.5%. Thus, an open circulation system that artificially simulates the strong self-purification ability of seawater is established.

10. The control method of the experimental apparatus for simulating the physicochemical environmental parameters of a submarine cold seep as described in claim 7, characterized in that: In S5, for the medium-speed cold seep simulation method, a methane gas source is used, which is pressurized by a gas booster (406), and the gas flow rate is monitored by a flow meter (407). The gas is injected into the distribution plate (105) through the methane gas injection port (408), and further diffused into the gas injection cavity (104). It continuously permeates through the sediment (103) and forms a small-scale plume on the surface of the sediment. In S5, for the rapid cold seep simulation method, that is, simulating the state of violent methane eruption caused by large-scale methane overflow after the formation becomes unstable, the methane gas source is pressurized by the gas booster (406), the gas flow rate is monitored by the flow meter (407), and the gas is injected into the fracture channel (106) through the methane gas injection port (408). The methane gas is broken up by the aeration head (107) to form a large-scale methane eruption and establish the rapid cold seep state.

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