A ship-based carbon dioxide ocean sequestration system, method, and storage medium

Abstract

This invention relates to the field of marine engineering and discloses a ship-based method and system for marine carbon dioxide sequestration. The system includes a carbon capture unit, a transport and storage unit, a pre-storage treatment unit, and a simulation unit. The simulation unit is used to load the ship's route and obtain ocean hydrology and geological environment data. By inputting the physical parameters of the dry ice, the ocean hydrology, and the geological environment, it simulates and calculates the required throwing angle and velocity for the dry ice to be thrown onto the deep-sea bed. A throwing and release unit is used to throw the dry ice onto the deep-sea bed according to the stated throwing angle and velocity. This ship-based method and system for marine carbon dioxide sequestration addresses current marine sequestration problems by employing the dry ice throwing principle, providing a new approach to carbon dioxide capture and sequestration with lower costs and less engineering difficulty.

Description

Technical Field

[0001] This invention relates to the field of prediction algorithms, and more particularly to a ship-based marine carbon dioxide sequestration system, method, and storage medium. Background Technology

[0002] Currently, carbon capture and storage technology is a mature technology for carbon dioxide emission reduction in onshore power plants, which brings the technological possibility of achieving large-scale carbon dioxide emission reduction in shipping as soon as possible. However, at present, marine storage is usually marine geological storage, which requires large-scale engineering construction, including drilling, injection, monitoring and other links, and has drawbacks such as high cost and great environmental impact. Summary of the Invention

[0003] The main objective of this invention is to solve the problems in the prior art. This invention provides a ship-based marine carbon dioxide storage system, which includes the following units:

[0004] A carbon capture unit, which is used to capture carbon dioxide from ship exhaust gas to obtain captured carbon dioxide;

[0005] A transport and storage unit, wherein the transport and storage unit is used to liquefy the captured carbon dioxide and transport it to a storage device;

[0006] A pre-sealing processing unit is used to solidify carbon dioxide in the storage device into dry ice, control the shape of the dry ice, and obtain the physical parameters of the dry ice.

[0007] The simulation calculation unit is used to load the ship's route, obtain ocean hydrology and geological environment, and simulate and calculate the throwing angle and speed required for dry ice to be thrown to the deep seabed by inputting the physical parameters of the dry ice, the ocean hydrology and the geological environment.

[0008] A throwing and releasing unit is used to throw the dry ice onto the deep seabed according to the throwing angle and speed.

[0009] The carbon capture unit includes an absorbent, an absorption tower, and a regeneration tower. The absorption tower is used to absorb carbon dioxide from ship exhaust gas. The absorbent is filled inside the absorption tower. The regeneration tower is used to separate the carbon dioxide absorbed in the absorption tower and release it under high temperature conditions. During the adsorption process, the absorbent adsorbs carbon dioxide gas. The heater heats the absorbent, desorbs the carbon dioxide gas, and reactivates the absorbent.

[0010] The transport and storage unit includes a compressor, a condenser, and a separator. The captured carbon dioxide is compressed to 2~2.5MPa. The high-temperature and high-pressure carbon dioxide gas is cooled to a low-temperature (-15~-25℃) and low-pressure state by passing through a condenser filled with a cooling medium. The liquefied carbon dioxide and the unliquefied carbon dioxide are separated to obtain liquid carbon dioxide.

[0011] Liquid carbon dioxide is stored in a storage tank. The transport and storage unit also includes a control unit for monitoring various state parameters of the liquid carbon dioxide.

[0012] The pre-storage processing unit includes an ocean and seabed site selection analysis unit, a carbon dioxide solidification unit, and a shape control unit. The ocean and seabed site selection analysis unit is used to establish a model of the storage path and storage location by loading the ship's route and inputting the ocean hydrology and seabed geological conditions below the route.

[0013] The carbon dioxide curing unit includes at least one compressor, evaporator, and cooler. Liquid carbon dioxide is compressed by the compressor and transferred to the evaporator. The liquid carbon dioxide is cured into dry ice in the shape control unit by reducing the temperature and pressure.

[0014] The shape control unit is used to form a "torpedo" structure with a shell and inner core made of dry ice and filled with liquid carbon dioxide.

[0015] During the calculation process, before entering the sea, the simulation unit simulates the trajectory of dry ice at different depths and its descent in the ocean based on the results of the pre-storage processing unit. It outputs relevant results, providing the required throwing angle and velocity for the dry ice to embed in the seabed. In the stage from the water surface to the seabed sedimentary layer, it uses fluid dynamics and heat / mass transfer analysis to simulate the time required to reach the seabed at that depth, based on the physical state and shape of carbon dioxide. It also calculates the initial velocity and carbon dioxide loss / leakage upon contact with the calcareous mud-covered seabed. In the stage from entering the seabed to deep burial, it simulates the resistance along the storage path, the embedding depth, and the storage conditions in the sedimentary layer of that soil type. It also considers basic parameters such as seabed soil conditions and calculates potential carbon dioxide leakage and storage stability throughout the storage process. Ultimately, this forms a complete carbon dioxide release and storage model for different marine and seabed environments.

[0016] The stage where dry ice enters seawater and reaches the surface of the seabed sediment layer is governed by continuity and momentum equations:

[0017]

[0018]

[0019] In the formula:

[0020] For gradient operators;

[0021] The velocity vector of the seawater flow;

[0022] This is the fluid pressure vector;

[0023] For time;

[0024] The density of seawater;

[0025] This represents the kinematic viscosity of the fluid.

[0026] Turbulent kinetic energy is defined using a turbulence model. With dissipation rate Transportation equations:

[0027]

[0028]

[0029] In the formula:

[0030] and Coordinate components

[0031] For velocity components

[0032] Molecular viscosity coefficient

[0033] Turbulent viscosity;

[0034] This is the term that generates turbulent kinetic energy k;

[0035] Given initial velocity components Determine the time step and parameters The displacement, velocity, and acceleration during the dry ice's sinking time can then be calculated:

[0036]

[0037]

[0038] When dry ice falls to a certain depth, its gravity and drag reach equilibrium, i.e., it reaches its terminal velocity.

[0039]

[0040] In the formula:

[0041] The terminal velocity of dry ice after it has sunk to a certain depth;

[0042] This represents the total mass of the dry ice.

[0043] This refers to the volume of dry ice.

[0044] The density of seawater;

[0045] The drag coefficient around dry ice;

[0046] The area of ​​the dry ice;

[0047] The above model can be used to calculate the time, speed, and path of dry ice from entering the sea surface to sinking to the seabed.

[0048] During the stage from when dry ice comes into contact with the seabed until it penetrates the seabed, according to the law of conservation of energy, the energy equation from when dry ice comes into contact with the seabed sediment until it penetrates and is buried deep and comes to rest is as follows:

[0049]

[0050] In the formula:

[0051] This is the gravitational potential energy of dry ice;

[0052] The kinetic energy of dry ice;

[0053] Work is done by friction on the outer side of the dry ice;

[0054] The dry ice tip inserts into the deposition layer and performs work through friction.

[0055] After determining the mass, diameter, friction coefficient, and nose tilt angle of the dry ice in the torpedo's shape, simulation calculations were performed to confirm the relationship between the terminal velocity and the burial depth, thus obtaining the depth to which the dry ice penetrated the sedimentary layer.

[0056]

[0057]

[0058] In the formula:

[0059] This refers to the volume of dry ice.

[0060] This refers to the burial depth;

[0061] The viscosity damping factor on the outer side of dry ice;

[0062] The outer diameter of the dry ice;

[0063] The coefficient of friction on the outer side of the dry ice;

[0064] The coefficient of friction of the dry ice head;

[0065] This refers to the tilt angle of the dry ice head.

[0066] The throwing and releasing unit consists of a robotic arm and an attitude control unit. The robotic arm is a 6-DOF robotic arm that grabs the dry ice and transfers it to the throwing point. It can also be equipped with a launching device to apply force and provide initial velocity for the released dry ice.

[0067] The attitude control unit is used to accurately position and control the attitude of the dry ice load. The attitude control unit consists of multiple sensors and a controller. The sensors monitor the direction, speed, angle and position parameters of the dry ice load, and the controller controls and adjusts the attitude of the dry ice based on the feedback information from the sensors.

[0068] The present invention also provides a ship-based method for marine carbon dioxide sequestration, the method comprising the following steps:

[0069] The carbon capture process involves capturing carbon dioxide from ship exhaust to obtain the captured carbon dioxide.

[0070] The transport and storage step involves liquefying the captured carbon dioxide and transporting it to a storage device.

[0071] The pre-sealing treatment step involves solidifying carbon dioxide into dry ice and controlling the shape of the dry ice to obtain its physical parameters.

[0072] The simulation calculation steps involve loading the ship's route, obtaining ocean hydrology and geological environment, and simulating the throwing angle and speed required for dry ice to be thrown onto the deep seabed by inputting the physical parameters of the dry ice, the ocean hydrology and the geological environment.

[0073] The throwing and releasing step involves throwing the dry ice onto the deep seabed at the throwing angle and speed.

[0074] The present invention also provides a computer-readable storage medium storing instructions that, when executed by a processor, implement the various steps of the ship-based marine carbon dioxide sequestration method.

[0075] Studies have shown that when dry ice is thrown into the sea and begins to sink, its surface rapidly evaporates. When the dry ice reaches a depth of 500 meters below the thermocline, the external pressure can reach 50 atmospheres, while the seawater temperature is approximately 5 degrees Celsius. Under these conditions, carbon dioxide cannot escape as a gas, and the surface of the dry ice partially liquefies. However, its density is still greater than that of seawater, so it continues to sink until it reaches the seabed. Throughout the entire sinking process, carbon dioxide loss can be controlled to within 2%, and the hydrated carbon dioxide formed on the surface of the dry ice during sinking also reduces this loss.

[0076] This invention relates to a method and system for marine carbon dioxide sequestration based on ships. Addressing the current marine sequestration problem, it adopts the principle of dry ice dropping and provides a new approach to carbon dioxide capture and sequestration with lower cost and less engineering difficulty. Attached Figure Description

[0077] Figure 1 This is a schematic diagram of a marine carbon dioxide sequestration system.

[0078] Figure 2 This is a schematic diagram of a carbon capture unit.

[0079] Figure 3 This is a schematic diagram of a transport storage unit.

[0080] Figure 4 This is a schematic diagram of the pre-sealing processing unit.

[0081] Figure 5 This is a schematic diagram of the simulation computing unit.

[0082] Figure 6 This is a schematic diagram of the throwing and releasing unit. Detailed Implementation

[0083] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” or “having,” and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or production apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or production apparatus.

[0084] To address the problems mentioned above, there is a need to develop a method for marine carbon sequestration after carbon dioxide capture from shipping vessels, forming a carbon capture and storage system for marine vessels. This would solve the current lack of effective technologies for marine carbon sequestration and alleviate the pressure on the shipping industry to reduce carbon emissions.

[0085] The present invention provides a marine carbon dioxide sequestration system for ships, which includes: a carbon capture unit, a transport and storage unit, a pre-storage treatment unit, a simulation and calculation unit, and a release unit.

[0086] The overall system route is attached. Figure 1 If the shipping vessel does not receive carbon dioxide from the shore, carbon dioxide will be captured from the vessel's exhaust during navigation and liquefied for storage on board. If the vessel receives some carbon dioxide from the shore, it will be directly liquefied and stored on board. Once the vessel reaches the target sea area, the carbon dioxide will be solidified and released for storage in areas meeting the release conditions through a pre-storage treatment unit and a simulation calculation unit. For sections of the voyage where the simulation calculation results are not ideal and release is not suitable, the vessel will maintain the carbon dioxide storage state and continue navigation until the release conditions are met.

[0087] Among them, as attached Figure 2 The carbon capture unit further includes a ship carbon capture device, which comprises at least one absorption tower, an absorbent, and a regeneration tower. Carbon capture on ships employs post-combustion carbon capture, which can use chemical absorption, physical adsorption, or membrane separation to absorb carbon dioxide gas by filling the absorption tower with an absorbent, and then desorbing and recycling it through the regeneration tower.

[0088] The absorption tower absorbs carbon dioxide from ship exhaust gas. It typically employs packed or plate structures to increase the contact area, thus facilitating the absorption process. Ship exhaust gas contains a large amount of water vapor and impurities, requiring pretreatment steps including condensation, filtration, and drying. Sulfur dioxide and other harmful gases are desulfurized through absorption, oxidation, and reduction methods to ensure that the SO2 content in the ship exhaust gas does not exceed 0.1%, the NOx content does not exceed 2500 ppm, the exhaust gas temperature is controlled between 100-200℃, the pressure is between 1-2 bar, and the CO2 content is not less than 15%.

[0089] The regeneration tower's function is to separate the carbon dioxide absorbed from the absorption tower and release it under high-temperature conditions. The regeneration tower comprises an absorbent bed, a regeneration gas delivery system, a heater, and a heat exchanger. During adsorption, the absorbent adsorbs carbon dioxide gas, separating it from the ship's exhaust gas. The heat exchanger transfers heat from the flue gas to the absorbent, promoting the absorption and separation of carbon dioxide. The heater then separately desorbs the carbon dioxide gas and reactivates the absorbent for reuse. Finally, the regeneration gas delivery system completes the carbon capture process in the ship's exhaust gas, achieving a carbon dioxide capture efficiency of over 80%.

[0090] Optionally, depending on the ship's route, carrying capacity, and carrying conditions, the ship may choose to receive carbon dioxide from the shore and store the carbon dioxide gas that needs to be sealed directly on board in liquid or solid form.

[0091] Among them, as attached Figure 3 The transport and storage unit includes a transport pipeline, a liquefaction device, a storage tank, and a control unit.

[0092] The conveying pipeline connects the various parts of the device and liquefies the captured carbon dioxide from the carbon capture unit through the liquefaction device and then transports it to the storage tank.

[0093] The specific liquefaction device also includes a compressor, a condenser, and a separator. Typically, a centrifugal, screw, or reciprocating compressor is used to compress the captured carbon dioxide to 2~2.5MPa. The high-temperature and high-pressure carbon dioxide gas passes through a condenser filled with a refrigerant or other cooling medium and is cooled to a low-temperature (-15 to -25℃) and low-pressure state. Further, molecular sieve, membrane separation, and other technologies are used to separate the liquefied carbon dioxide from the unliquefied carbon dioxide, thereby improving liquefaction efficiency and purity, and obtaining liquid carbon dioxide with a purity of over 99.9%.

[0094] The storage tank is strong enough to meet the temperature and pressure requirements for storing liquid carbon dioxide. The selectable tank pressure is 3.5-4.5 MPa, and the temperature is 0-10°C. It has good thermal insulation and corrosion resistance, ensuring the quality and stability of liquid carbon dioxide storage on ships.

[0095] The control unit is used to monitor and control various state parameters of liquid carbon dioxide, such as pressure, temperature, flow rate, and liquid level. Based on the real-time monitored data, it adjusts the pressure, temperature, and flow rate parameters to ensure stable system operation and compliance with environmental and safety standards. Furthermore, the control unit has remote monitoring and operation control functions, which improves the system's automation level and safety performance while reducing the risk of human error and misoperation.

[0096] Among them, as attached Figure 4The pre-sealage processing unit further includes a site selection analysis unit, a carbon dioxide curing unit, and a dry ice shape control unit.

[0097] The site selection analysis unit, by loading the ship's route and inputting the marine hydrological and seabed geological conditions below the route, establishes a model of the sequestration path and location. This ensures that the sequestration site is located on the seabed covered by calcareous mud at a depth of over 3000 meters, meeting the sequestration volume requirements. Selecting a seabed at a depth greater than 3000 meters covered by calcareous mud as the sequestration route ensures the stability and reliability of the sequestration effect, while also protecting the marine ecological environment and reducing the impact on the marine ecosystem.

[0098] Alternatively, seabeds with water depths of 500m or more and overlapping hydrate formation zones (HFZ) and negative buoyancy zones (NBZ) are also safe carbon sequestration sites. Carbon dioxide will reach a gravitationally stable state here, at most moving to the top of the NBZ, and will be blocked from escaping by the pore water of the caprock, thus playing a role in safe sequestration.

[0099] The carbon dioxide solidification unit comprises at least one compressor, evaporator, and refrigerator. Liquid carbon dioxide captured and stored on the ship is compressed by the compressor and transferred to the evaporator. By reducing temperature and pressure, the liquid carbon dioxide is solidified in a shape control unit using a mold into torpedo-shaped dry ice with a diameter of approximately 450 mm and a length of approximately 4 m. The density of the compressed dry ice must reach 1.6 tons per cubic meter, and the compression degree is controlled between 90% and 100% to achieve the desired dry ice strength and density, ensuring that the released dry ice can reach the target sinking speed of 15-25 m / s without disintegrating.

[0100] Optionally, the shape control unit can form a "torpedo" structure with a shell and inner core of dry ice and filled with liquid carbon dioxide inside, in order to reduce the energy consumed to solidify the liquid carbon dioxide, while adding weight to the head to achieve the desired density.

[0101] Among them, as attached Figure 5The simulation unit performs simulation calculations by inputting the physical state parameters of dry ice and the marine hydrological and geological environment. During the calculation, the interaction between dry ice and the surrounding marine environment is considered, including the effects of dry ice phase changes and gas release, ocean temperature, salinity, and other factors. Before entering the sea, based on the results of the pre-sealing processing unit showing the course and seabed conditions, the unit simulates and calculates the settling trajectory of dry ice at different depths, as well as its descent in the ocean, and outputs relevant results, providing the throwing angle and velocity required for the dry ice to embed in the seabed. During the stage from the water surface to the seabed sedimentary layer, the settling dynamics of the dry ice are simulated using fluid dynamics and heat and mass transfer analysis. Based on the physical state and shape of carbon dioxide, the unit calculates the time required to reach the seabed at that depth, as well as the initial velocity and carbon dioxide loss / leakage upon contact with the calcareous mud-covered seabed. During the seabed entry and deep burial storage stage, the resistance along the storage path, the embedment depth and storage status under the sedimentary layer of this soil type are simulated and calculated. At the same time, basic parameters such as seabed soil conditions are also considered, as well as the potential leakage of carbon dioxide and the storage stability during the entire storage process. Finally, a complete set of carbon dioxide release and storage models for different marine and seabed environments is formed, and the expected drop and storage locations and the storage status of the inserted sedimentary layer are obtained.

[0102] The stage where dry ice enters seawater and reaches the surface of the seabed sediment layer is governed by continuity and momentum equations:

[0103]

[0104]

[0105] In the formula:

[0106] For gradient operators;

[0107] The velocity vector of the seawater flow;

[0108] This is the fluid pressure vector;

[0109] For time;

[0110] The density of seawater;

[0111] This represents the kinematic viscosity of the fluid.

[0112] Turbulent kinetic energy is defined using a turbulence model. With dissipation rate Transportation equations:

[0113]

[0114]

[0115] In the formula:

[0116] and Coordinate components

[0117] For velocity components

[0118] Molecular viscosity coefficient

[0119] Turbulent viscosity;

[0120] This is the term that generates turbulent kinetic energy k;

[0121] Given initial velocity components Determine the time step and parameters The displacement, velocity, and acceleration during the dry ice's sinking time can then be calculated:

[0122]

[0123]

[0124] When dry ice falls to a certain depth, its gravity and drag reach equilibrium, i.e., it reaches its terminal velocity.

[0125]

[0126] In the formula:

[0127] The terminal velocity of dry ice after it has sunk to a certain depth;

[0128] This represents the total mass of the dry ice.

[0129] This refers to the volume of dry ice.

[0130] The density of seawater;

[0131] The drag coefficient around dry ice;

[0132] The area of ​​the dry ice;

[0133] The above model can be used to calculate the time, speed, and path of dry ice from entering the sea surface to sinking to the seabed.

[0134] During the stage from when dry ice comes into contact with the seabed until it penetrates the seabed, according to the law of conservation of energy, the energy equation from when dry ice comes into contact with the seabed sediment until it penetrates and is buried deep and comes to rest is as follows:

[0135]

[0136] In the formula:

[0137] This is the gravitational potential energy of dry ice;

[0138] The kinetic energy of dry ice;

[0139] Work is done by friction on the outer side of the dry ice;

[0140] The dry ice tip inserts into the deposition layer and performs work through friction.

[0141] After determining the mass, diameter, friction coefficient, and nose tilt angle of the dry ice in the torpedo's shape, simulation calculations were performed to confirm the relationship between the terminal velocity and the burial depth, thus obtaining the depth to which the dry ice penetrated the sedimentary layer.

[0142]

[0143]

[0144] In the formula:

[0145] This refers to the volume of dry ice.

[0146] This refers to the burial depth;

[0147] The viscosity damping factor on the outer side of dry ice;

[0148] The outer diameter of the dry ice;

[0149] The coefficient of friction on the outer side of the dry ice;

[0150] The coefficient of friction of the dry ice head;

[0151] This refers to the tilt angle of the dry ice head.

[0152] Based on the results of the pre-storage processing unit and the simulation calculation unit, if the hydrology, geology, storage capacity, legal conditions, etc. of the target sea area do not meet the storage requirements, the prepared dry ice or liquid carbon dioxide will be kept in storage until the ship sails to other sections and the simulation calculation results meet the release conditions before the release operation is carried out.

[0153] Among them, as attached Figure 6 The throwing and releasing unit consists of at least two parts: a robotic arm and an attitude control unit.

[0154] The robotic arm is a 6-DOF (DoF) robotic arm that grasps solidified dry ice and transfers it to the throwing point. It is equipped with a throwing propulsion device to apply a certain force, providing initial velocity for the released dry ice. The robotic arm is mainly installed on the port and starboard sides of the ship and consists of multiple joints, each capable of rotation and extension. Its end is equipped with a gripper or suction cup for grasping the dry ice and a hydraulic launching device for pushing the dry ice, ensuring it reaches the target throwing speed. The movement of the robotic arm is controlled by a controller. The robotic arm's dynamic equations are programmed to automate its operation, accurately positioning and grasping the dry ice, ensuring it is securely attached to the gripper or suction cup while avoiding damage, and finally placing the dry ice on the predetermined throwing point track.

[0155] Optionally, for special vessels, the robotic arm is installed in the moon pool in the middle of the hull, and due to the special nature of the moon pool drop operation, the size and weight of the "torpedo"-shaped dry ice can be increased to achieve a large amount of carbon dioxide sequestration in a single drop operation.

[0156] The attitude control unit accurately positions and controls the attitude of the dry ice load, maintaining good stability during deployment. Sensors monitor and adjust the direction, velocity, and angle parameters of the dry ice load in real time to ensure that the dry ice embeds vertically into the target seabed after deployment for sealing purposes. The attitude control unit consists of multiple sensors and a controller. The sensors monitor the direction, velocity, angle, and position parameters of the dry ice load, while the controller controls and adjusts the attitude of the dry ice based on the feedback information from the sensors.

[0157] The release unit releases dry ice, or a mixture of dry ice and liquid carbon dioxide, with a density of approximately 1.6 tons per cubic meter, into the sea at a certain initial velocity. This method achieves a penetration depth of nearly 10 meters into soft sediments on the deep seabed. The collapse triggered by the dry ice penetrating the sediments provides excellent self-sealing. Furthermore, the solid carbon dioxide shell undergoes physical and chemical reactions with the sediments before reacting with the seawater, ultimately forming stable hydrates under the pressure and temperature of the deep sea, providing a sequestration effect that can last for centuries.

[0158] This invention also provides a carbon sequestration method using the above-mentioned marine carbon dioxide sequestration system, comprising:

[0159] The first step is to liquefy carbon dioxide gas and store it on the ship. During the ship's voyage, the solidification device compresses it into dry ice in the shape of a "torpedo" and then a robotic arm grabs and transports it to the ship's drop and storage point.

[0160] The second step is to obtain ship routes and seabed geological and hydrological information, and then determine the sections that meet the requirements for marine casting operations after simulation calculations.

[0161] The third step involves the ship dropping and sealing solid carbon dioxide when it reaches the target section. The solid carbon dioxide is pushed into the sea by a robotic arm and sinks to the target seabed under its own weight, where it is inserted into the seabed sediment layer to achieve sealing.

[0162] In the first step, dry ice is prepared from liquid carbon dioxide using a vaporization dry ice production technology. This involves throttling and vaporizing liquid carbon dioxide, separating the gaseous carbon dioxide, and then compressing and releasing heat to solidify a portion of the carbon dioxide into snow-like form to produce dry ice. Since the vaporization of liquid carbon dioxide removes a significant amount of heat, creating a low-temperature environment, partial carbon dioxide vaporization can be used to produce dry ice with lower energy consumption. The ratio of dry ice production to vaporized carbon dioxide is 1:1.2. Finally, the dry ice is compressed to form a torpedo-shaped piece with a density of 1.6 tons / cubic meter, a diameter of approximately 450 mm, and a length of approximately 4 m. The vaporized carbon dioxide is recycled and reused in the storage process.

[0163] In the second step, the suitable sea segment for carbon dioxide release and storage should meet the following requirements: the target area is the seabed where the HFZ and NBZ overlap at a depth of more than 500m, or the seabed covered by calcareous mud at a depth of more than 3000m.

[0164] In the third step, the robotic arm adjusts the angle and initial velocity of the dry ice. After entering the sea, the dry ice relies on its own weight to maintain a vertical sinking state. When it reaches the seabed, its speed reaches 15-25 m / s, and it is inserted into the seabed sediment layer to achieve sealing.

[0165] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A ship-based carbon dioxide ocean sequestration system, characterized by, The sealing system includes the following units: A carbon capture unit, which is used to capture carbon dioxide from ship exhaust gas to obtain captured carbon dioxide; A transport and storage unit, wherein the transport and storage unit is used to liquefy the captured carbon dioxide and transport it to a storage device; A pre-sealing processing unit is used to solidify carbon dioxide in the storage device into dry ice, control the shape of the dry ice, and obtain the physical parameters of the dry ice. The simulation calculation unit is used to load the ship's route, obtain the marine hydrology and geological environment, and simulate and calculate the throwing angle and speed required for the dry ice to be thrown onto the deep seabed by inputting the physical parameters of the dry ice, the marine hydrology and the geological environment. A throwing and releasing unit is used to throw the dry ice onto the deep seabed according to the throwing angle and speed. During the calculation process, before entering the sea, the simulation unit simulates the trajectory of dry ice at different depths and its descent in the ocean based on the results of the pre-storage processing unit. It outputs relevant results, providing the throwing angle and speed required for the dry ice to embed in the seabed. In the stage from the water surface to the seabed sedimentary layer, it uses fluid dynamics and heat and mass transfer analysis methods to simulate the time required to enter the seabed at that depth based on the physical state and shape of carbon dioxide. It also calculates the initial velocity and carbon dioxide loss / leakage when contacting the seabed covered by calcareous mud. In the stage from entering the seabed to deep burial and storage, it simulates the resistance along the storage path and the embedding depth and storage conditions under the soil-type sedimentary seabed. It also considers the basic parameters of the seabed soil conditions and calculates the possible leakage problems and storage stability of carbon dioxide throughout the storage process. Finally, it forms a complete carbon dioxide throwing and storage mode for different marine and seabed environments. The stage where dry ice enters seawater and reaches the surface of the seabed sediment layer is governed by continuity and momentum equations: In the formula: is the gradient operator; V is the sea water flow velocity vector; is the fluid pressure vector; t is time; where p is the density of seawater; For the kinematic viscosity of a fluid; Defining the turbulent kinetic energy by the turbulence model with the dissipation rate Transport equation: In the formula: and for the coordinate components for the velocity component viscosity coefficient of the molecule wherein: v is the velocity of the fluid; D is the diffusion coefficient; r is the radius of the is a production term for the turbulent kinetic energy k; Given the initial velocity component , the time step , and the parameters , the displacement, velocity, and acceleration during the dry ice sinking time period can be found: When dry ice falls to a certain depth, its gravity and drag reach equilibrium, i.e., it reaches its terminal velocity. In the formula: Vt is the terminal velocity of dry ice sinking a certain depth; This represents the total mass of the dry ice. Volume of dry ice; where p is the density of seawater; Cp is the drag coefficient for dry ice flow around the body; Dry ice area; The above model can be used to calculate the time, speed, and path of dry ice from entering the sea surface to sinking to the seabed. During the period from when dry ice comes into contact with the seabed until it penetrates the seabed, according to the law of conservation of energy, the energy equation from when dry ice comes into contact with the seabed sediment until it penetrates and is buried deep and comes to rest is as follows: In the formula: Dry ice gravity potential energy; Kinetic energy of dry ice; Work on the outside of the dry ice; Dry ice head inserts friction work into the deposited layer After determining the mass, diameter, friction coefficient, and nose tilt angle of the dry ice in the torpedo's shape, simulation calculations were performed to confirm the relationship between the terminal velocity and the burial depth, thus obtaining the depth to which the dry ice penetrated the sedimentary layer. In the formula: Dry ice volume; depth of burial; is the dry ice outer viscous damping factor; D is the outside diameter of dry ice; For dry ice outside friction factor; Dry ice head friction factor; The angle of inclination of the dry ice head.

2. A ship-based carbon dioxide ocean sequestration system according to claim 1, wherein, The carbon capture unit includes an absorbent, an absorption tower, and a regeneration tower. The absorption tower is used to absorb carbon dioxide from ship exhaust gas. The absorbent is filled inside the absorption tower. The regeneration tower is used to separate the carbon dioxide absorbed in the absorption tower and release it under high temperature conditions. During the adsorption process, the absorbent adsorbs carbon dioxide gas. Heating the absorbent desorbs the carbon dioxide gas and reactivates the absorbent.

3. A ship-based carbon dioxide ocean sequestration system according to claim 1, wherein, The transport and storage unit includes a compressor, a condenser, and a separator. The captured carbon dioxide is compressed to 2~2.5MPa. The high-temperature and high-pressure carbon dioxide gas is cooled to a low-temperature and low-pressure state by passing through a condenser filled with a cooling medium. The liquefied carbon dioxide and the unliquefied carbon dioxide are separated to obtain liquid carbon dioxide. The low temperature is -15 to -25℃. Liquid carbon dioxide is stored in a storage tank. The transport and storage unit also includes a control unit for monitoring various state parameters of the liquid carbon dioxide.

4. A ship-based carbon dioxide ocean sequestration system according to claim 1, wherein, The pre-storage processing unit includes an ocean and seabed site selection analysis unit, a carbon dioxide solidification unit, and a shape control unit. The ocean and seabed site selection analysis unit is used to establish a model of the storage path and storage location by loading the ship's route and inputting the ocean hydrology and seabed geological conditions below the route. The carbon dioxide curing unit includes at least one compressor, evaporator, and cooler. Liquid carbon dioxide is compressed by the compressor and transferred to the evaporator. The liquid carbon dioxide is cured into dry ice in the shape control unit by reducing the temperature and pressure. The shape control unit is used to form a torpedo structure with a shell and inner core made of dry ice and an interior filled with liquid carbon dioxide.

5. A ship-based carbon dioxide ocean sequestration system according to claim 1, wherein, The throwing and releasing unit consists of a robotic arm and an attitude control unit. The robotic arm is a 6-DOF robotic arm that grabs the dry ice and transfers it to the throwing point. It can also be equipped with a launching device to apply force and provide initial velocity for the released dry ice. The attitude control unit is used to accurately position and control the attitude of the dry ice load. The attitude control unit consists of multiple sensors and a controller. The sensors monitor the direction, speed, angle and position parameters of the dry ice load, and the controller controls and adjusts the attitude of the dry ice based on the feedback information from the sensors.

6. A ship-based method of carbon dioxide ocean sequestration, characterized by, The storage method is based on the carbon dioxide marine storage system of claim 1 and includes the following steps: The carbon capture process involves capturing carbon dioxide from ship exhaust to obtain the captured carbon dioxide. The transport and storage step involves liquefying the captured carbon dioxide and transporting it to a storage device. The pre-sealing treatment step involves solidifying carbon dioxide into dry ice and controlling the shape of the dry ice to obtain its physical parameters. The simulation calculation steps involve loading the ship's route, obtaining the marine hydrology and geological environment, and simulating the throwing angle and speed required for the dry ice to be thrown onto the deep seabed by inputting the physical parameters of the dry ice, the marine hydrology and the geological environment. The throwing and releasing step involves throwing the dry ice onto the deep seabed at the throwing angle and speed.

7. A computer-readable storage medium having stored thereon instructions, the computer-readable storage medium comprising: When the instructions are executed by the processor, they implement the various steps of the ship-based marine carbon dioxide sequestration method as described in claim 6.

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