Method and system for capturing and storing carbon dioxide in offshore sandstone CCUS system
Through geological evaluation and absorber formulation optimization, layered injection strategies and monitoring systems, the problems of low carbon dioxide capture efficiency and insufficient storage safety in offshore sandstone CCUS systems are solved, and efficient and safe carbon dioxide capture and storage are achieved, and protection is achieved. marine ecosystems.
Patent Information
- Application Number
- CN202411372810.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-29
- Publication Date
- 2025-01-03
AI Technical Summary
Inefficient carbon dioxide capture in offshore sandstone CCUS systems, devices are susceptible to corrosion, and ensuring long-term safe storage and leakage prevention in dynamic marine environments is a challenge, while minimizing negative impacts on marine ecosystems.
Select suitable storage areas through geological assessment, configure absorbents that are suitable for the marine environment, create a layered injection system and monitor pressure changes, and use active ingredients such as amine-containing compounds and antisalts, combined with seismic monitoring and environmental impact assessment to ensure carbon dioxide Stable storage and security.
Improves efficiency and safety of CO2 capture and storage, ensures security of long-term storage, and minimizes negative impacts on marine ecosystems.
Smart Images
Figure CN119244315A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of offshore sandstone CCUS, and in particular to a method and system for capturing and storing carbon dioxide in an offshore sandstone CCUS system. Background Art
[0002] In the offshore sandstone CCUS system, the capture and storage of carbon dioxide faces several key technical issues: high-efficiency carbon capture: under high salinity and humidity conditions in the marine environment, the efficiency of traditional carbon capture technology is reduced, and the equipment is susceptible to corrosion; safe and stable carbon dioxide storage: in a dynamic marine environment, it is a challenge to ensure long-term and safe storage of carbon dioxide and prevent leakage; environmental impact: it is necessary to minimize the negative impact of CCUS operations on the marine ecosystem. That is, the existing technology has the following problems and defects: 1. The efficiency of traditional carbon capture technology is reduced, and the equipment is susceptible to corrosion; 2. In a dynamic marine environment, it is a challenge to ensure long-term and safe storage of carbon dioxide and prevent leakage; 3. It is necessary to minimize the negative impact of CCUS operations on the marine ecosystem. Summary of the invention
[0003] The present invention is intended to provide a method and system for capturing and storing carbon dioxide in an offshore sandstone CCUS system, so as to improve the efficiency and safety of carbon dioxide capture and storage.
[0004] In order to achieve the above object, the present invention adopts the following technical scheme:
[0005] CO2 capture and storage methods in offshore sandstone CCUS systems include:
[0006] S1, conduct geological assessment and obtain the storage area of carbon dioxide based on the assessment results;
[0007] S2, configure absorbent suitable for the marine environment of the storage area;
[0008] S3, creating a CO2 injection system to inject CO2 into offshore sandstone layers according to a layered injection strategy;
[0009] S4, monitors the pressure changes during the injection process and issues an automatic warning when the pressure is abnormal.
[0010] The principles and advantages of this solution are: in actual application, geological assessment is carried out, and the storage area of carbon dioxide is obtained according to the assessment results, so as to select sandstone layers with good sealing and storage adaptability; absorbents suitable for the marine environment of the storage area are configured to improve the environmental adaptability of the absorbent, thereby improving the carbon dioxide capture efficiency of the absorbent;
[0011] Monitor pressure changes during the injection process to prevent over-injection and potential leakage. Create a carbon dioxide injection system to inject carbon dioxide into offshore sandstone layers according to the layered injection strategy. The carbon dioxide injection system includes compression equipment, transmission pipelines and injection wells. Through layered injection, the stable storage of carbon dioxide in the seabed sandstone layer is ensured; monitor pressure changes during the injection process, and automatically warn when the pressure is abnormal to ensure the safety of carbon dioxide injection and storage.
[0012] Preferably, as an improvement, the S1 further includes a leakage path for evaluating the integrity of the geological structure.
[0013] Technical effect: easy to ensure the safety of long-term storage.
[0014] Preferably, as an improvement, the active ingredient of the absorbent includes an amine-containing compound, and the amine-containing compound includes one of diethanolamine or monoethanolamine.
[0015] Technical effect: Facilitates the capture of carbon dioxide.
[0016] Preferably, as an improvement, S2 includes:
[0017] S21, determining an absorbent formula, wherein the formula includes an active ingredient, an ionic liquid, a solid adsorbent, a salt-resistant agent, a temperature-resistant agent, and an alkaline buffer;
[0018] S22, preparing sample formulas according to a preset ratio range to obtain different absorbent samples;
[0019] S23, testing the absorbent sample, wherein the test includes a baseline test, a durability and adaptability test, and a regeneration ability test;
[0020] S24, obtaining a final absorbent formula according to the test results.
[0021] Technical effect: It is easy to optimize the composition of the absorbent to achieve the best capture efficiency and adaptability to the marine environment.
[0022] Preferably, as an improvement, S3 includes:
[0023] S31, obtaining injection parameters of the injection well according to the geological structure and fluid dynamics simulation results;
[0024] S32, adopts a layered injection strategy, increases the CO2 injection amount layer by layer, and injects the captured CO2 into the sandstone layer.
[0025] Technical Effect: Facilitates balancing formation pressure and maximizing storage efficiency.
[0026] Preferably, as an improvement, S4 includes:
[0027] S41, monitors the injection parameters of the carbon dioxide injection process in real time through the installed pressure and temperature sensors, and adjusts the injection strategy according to the injection parameters;
[0028] S42, regularly detects potential CO2 leaks and ground movement through seismic monitoring technology and ground deformation observations.
[0029] Technical effect: It is easy to ensure the safety of the carbon dioxide storage process.
[0030] Preferably, as an improvement, the method further includes S5, conducting an environmental impact assessment, wherein the environmental impact assessment includes an ecotoxicity assessment, a biodegradability and accumulation assessment, and an environmental release assessment.
[0031] Technical effect: It is convenient to protect the marine ecological safety during the capture and storage of carbon dioxide.
[0032] The carbon dioxide capture and storage system in the offshore sandstone CCUS system uses the carbon dioxide capture and storage method in the offshore sandstone CCUS system. BRIEF DESCRIPTION OF THE DRAWINGS
[0033] Figure 1 A schematic diagram of the process of carbon dioxide capture and storage in an offshore sandstone CCUS system;
[0034] Figure 2 Schematic diagram of the structure of the pipeline system in an embodiment of the present invention. DETAILED DESCRIPTION
[0035] The following is further described in detail through specific implementation methods:
[0036] The embodiment is basically as shown in the attached Figure 1 As shown:
[0037] CO2 capture and storage methods in offshore sandstone CCUS systems include:
[0038] S1, conduct geological assessment, and obtain the storage area of carbon dioxide based on the assessment results; specifically, conduct seabed geological surveys, collect rock samples for analysis, and use a variety of geophysical methods for comprehensive detection. Specifically, analyze the stratum structure and potential faults through seismic exploration methods, and use the propagation characteristics of seismic waves in different strata to identify the distribution and properties of rock formations; use electromagnetic methods to detect changes in underground resistivity, thereby indirectly inferring the water content and porosity of rock formations; use gravity exploration to measure small changes in the earth's gravity field and infer the distribution of underground density, and then analyze the integrity of rock formations and potential storage space. By combining the above methods, comprehensively evaluate the integrity and porosity of the capping rock formations of potential reservoirs. According to the results of geological surveys, select sandstone layers with good sealing and suitable storage capacity as the storage area of carbon dioxide, and ensure that the selected storage area is away from active faults and sensitive ecological areas; when selecting a site, comprehensively consider the safety of the geological structure, storage capacity and the impact on the surrounding environment. The best storage location has sufficient capacity, good sealing and geological stability, and low-risk environmental sensitivity.
[0039] The S1 also includes leakage paths to evaluate the integrity of the geological structure. The leakage paths include potential leakage channels such as fractures, fissures and joints in the strata. By combining geological modeling and numerical simulation technology, the leakage paths are predicted and analyzed to ensure the integrity of the geological structure of the selected storage area and the safety of long-term storage.
[0040] S2, configure an absorbent suitable for the marine environment of the storage area; the active ingredient of the absorbent includes an amine compound, and the amine compound includes one of diethanolamine or monoethanolamine; diethanolamine (DEA) has high absorption efficiency, but its corrosion resistance and reaction with seawater need to be considered; monoethanolamine (MEA) has a faster absorption rate and is suitable for capturing high-concentration CO2. S2 includes:
[0041] S21, determine the absorbent formula, the formula includes active ingredients, ionic liquids, solid adsorbents, anti-salt agents, temperature-resistant agents, and alkaline buffers; ionic liquids are selected with low evaporation rates and high chemical stability, and ionic liquids have good selectivity and adjustability, and are suitable for use in marine environments; solid adsorbents such as metal organic frameworks (MOFs) or activated carbon, solid adsorbents are convenient to provide high stability and low environmental impact; anti-salt agents such as sodium sulfate or calcium chloride are used to reduce the impact of salt in seawater on the absorption process; temperature-resistant agents such as glycerol or ethylene glycol help the absorbent maintain stable performance in an environment with large temperature fluctuations; alkaline buffers such as sodium carbonate or sodium bicarbonate are used to neutralize acidic substances generated during the absorption process to reduce corrosion to equipment.
[0042] S22, prepare the sample formula according to the preset ratio range to obtain different absorbent samples; the preset ratio range is specifically as follows: DEA or MEA: 30-60% volume ratio; ionic liquid: 10-30% volume ratio; solid adsorbent: added as needed, determined by adsorption efficiency and material compatibility; additives (anti-salt agent, anti-temperature agent, alkaline buffer): the total amount does not exceed 10% volume ratio. When determining the proportion of each component of the absorbent, the present invention has carried out a large number of experimental studies and data analysis, and obtained an optimized ratio range by comparing the absorption performance, stability and environmental adaptability under different ratio combinations: DEA or MEA accounts for 30-60% of the total volume, ensuring efficient carbon dioxide absorption capacity; ionic liquid accounts for 10-30% of the total volume, ensuring low evaporation rate and high chemical stability, which helps to improve the overall performance of the absorbent; solid adsorbent is added according to actual needs to ensure optimal adsorption efficiency and material compatibility; the total amount of additives (including salt-resistant agents, temperature-resistant agents and alkaline buffers) is controlled to a volume ratio of no more than 10% to balance the stability and environmental adaptability of the absorbent. Based on the above ratios, the optimal carbon dioxide capture efficiency and environmental friendliness can be achieved.
[0043] S23, testing the absorbent samples, the tests including baseline test, durability and adaptability test, and regeneration capacity test; wherein, the baseline test refers to testing the basic absorption performance of each absorbent sample, recording the carbon dioxide absorption rate and capacity; the durability and adaptability test refers to long-term operation test in a simulated marine environment, including performance under high salinity and temperature fluctuation conditions; the regeneration capacity test refers to evaluating the regeneration efficiency and reuse performance of the absorbent.
[0044] S24, obtain the final absorbent formula based on the test results to optimize the composition of the absorbent so that it can effectively react chemically with carbon dioxide in the high humidity and high salinity environment of the ocean to achieve the best capture efficiency and environmental adaptability.
[0045] In this embodiment, the absorption tower is also optimized according to the final absorbent formula, including the optimization of the tower structure and the packing method, so that the absorption tower has a larger contact area, improving the contact efficiency between carbon dioxide and the absorbent, thereby further improving the capture efficiency of carbon dioxide.
[0046] S3, creating a carbon dioxide injection system, injecting carbon dioxide into the offshore sandstone layer according to the layered injection strategy, the carbon dioxide injection system includes compression equipment, a transmission pipeline and an injection well; the compression equipment is used to compress the captured carbon dioxide to a suitable pressure so as to safely transmit it over long distances through the transmission pipeline; in this embodiment, the transmission pipeline is a high-pressure pipeline system, which has excellent corrosion resistance and sealing properties to ensure that carbon dioxide will not leak during transmission; the injection well is used to inject carbon dioxide into the offshore sandstone layer, and is set based on the characteristics of the formation and the injection pressure requirements to ensure that carbon dioxide can be evenly and effectively injected into the selected storage area; the compression equipment, the transmission pipeline and the injection well can achieve an efficient and safe carbon dioxide injection process.
[0047] The carbon dioxide injection system also includes a stable base and a pipeline system, the pipeline system is a high-pressure pipeline system, such as Figure 2 As shown, the pipeline system includes a valve system and a safety and monitoring system. The stable base is used to ensure that the device can remain stable even under strong currents and wind and waves; the pipeline system is used to ensure that carbon dioxide is safely transported to the storage location and monitored to detect leaks and take quick response measures; the safety and monitoring system is used to monitor parameters such as pressure, temperature and flow, and implement regular inspections and maintenance plans to ensure the long-term safe operation of the system. In this embodiment, the stable base includes a self-sinking base and an anchored base. The self-sinking base can sink to the seabed by itself and then be fixed on the seabed by weighting or anchoring; the anchored base fixes the device to an anchor point pre-installed on the seabed by an anchor chain or steel cable. The pipeline system uses high-pressure and corrosion-resistant pipeline materials, such as titanium alloy or steel pipes with special coatings, and adopts flexible pipeline connection methods, such as using bellows segments, to absorb movement and vibration in the marine environment; multiple safety valves and monitoring points are set in the pipeline system, and automatic or remotely operated valves are set at key locations to facilitate the control of carbon dioxide flow and emergency shut-off; the valve system includes pressure release and pressure relief devices to prevent system over-pressurization; the entire pipeline system is equipped with sensors to monitor parameters such as pressure, temperature and flow.
[0048] The S3 includes: S31, obtaining the injection parameters of the injection well according to the geological structure and fluid dynamics simulation results; the injection parameters include pressure and injection rate. Specifically, firstly, a detailed geological structure analysis is performed on the target sandstone layer, and the geological structure analysis includes key parameters such as the thickness, porosity, and permeability of the rock layer; then, the flow and diffusion of carbon dioxide in the sandstone layer is simulated using a fluid dynamics model, and the optimal injection pressure and injection rate under different rock formation conditions are determined through the simulation results, thereby ensuring that carbon dioxide can be uniformly and effectively injected into the sandstone layer.
[0049] S32, adopting a layered injection strategy, increasing the injection amount of carbon dioxide layer by layer, and injecting the captured carbon dioxide into the sandstone layer. Specifically, the target sandstone layer is divided into multiple sub-layers, each with different thickness and physical properties. During the injection process, the present invention first selects the lower sub-layer as the starting injection layer, and injects carbon dioxide into the layer with a moderate pressure and speed through a high-pressure pump; when the layer reaches the predetermined storage capacity, the injection parameters of the injection well are gradually adjusted upward to inject carbon dioxide into the upper sub-layer; injection is performed layer by layer until all sub-layers are effectively filled. Through the layered injection strategy, it is ensured that carbon dioxide is stored in layers in the sandstone layer, maximizing the storage capacity and reducing the risk of leakage.
[0050] S4, monitoring the pressure changes during the injection process, and automatically warning when the pressure is abnormal. S4 includes:
[0051] S41, in order to ensure the safety and effectiveness of the injection process, in the carbon dioxide injection system, a number of monitoring devices such as pressure sensors and temperature sensors are installed at different depths of the injection well and on key flow paths to monitor the pressure and temperature changes during the carbon dioxide injection process in real time. When abnormal key parameters are detected, such as a sudden increase in pressure or abnormal temperature changes, the system will automatically trigger the early warning mechanism. At the same time, the injection strategy is dynamically adjusted based on real-time monitoring data. For example, if the pressure suddenly rises somewhere, the injection operation is stopped immediately, and the area is inspected in detail to eliminate safety hazards to prevent formation rupture or carbon dioxide leakage; if the temperature sensor shows that the temperature is too high somewhere, indicating potential chemical reactions or formation friction heat, the injection point is adjusted or the injection speed is reduced to ensure safety.
[0052] S42, through seismic monitoring technology and ground deformation observation, regular detection of potential CO2 leakage and stratum movement is carried out to ensure the safety of the CO2 storage process.
[0053] Seismic monitoring technology uses seismic detectors placed on the surface or underground to capture tiny vibrations in the strata. The vibrations are caused by changes in stratum stress, fluid flow, or stratum movement. By analyzing the vibration signals, abnormal stratum activities can be discovered in time, thereby warning of potential leaks or geological risks. Ground deformation observation uses measuring equipment to monitor tiny deformations on the surface. Deformations are caused by underground carbon dioxide injection or stratum movement. Through regular observation and analysis, the stability of underground storage space is evaluated and any possible safety hazards are discovered in time.
[0054] It also includes S5, conducting an environmental impact assessment, which includes an ecotoxicity assessment, a biodegradability and accumulation assessment, and an environmental release assessment. The ecotoxicity assessment is to assess the potential impact of the absorbent on marine organisms, including acute and chronic toxicity tests on common marine organisms such as plankton, corals, and fish; the biodegradability and accumulation assessment is to study the biodegradability of the absorbent and its degradation products to ensure that they will not accumulate in the marine environment for a long time and cause environmental problems. The environmental release assessment is to simulate the accidental leakage of the absorbent, assess its short-term and long-term impact on the marine environment, and formulate corresponding risk control and emergency response strategies.
[0055] The carbon dioxide capture and storage system in the offshore sandstone CCUS system uses the carbon dioxide capture and storage method in the offshore sandstone CCUS system.
[0056] The above is only an embodiment of the present invention, and the common knowledge such as the known specific technical solutions and / or characteristics in the solution is not described in detail here. It should be pointed out that for those skilled in the art, without departing from the technical solution of the present invention, several modifications and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.
Claims
1. A method for capturing and storing carbon dioxide in an offshore sandstone CCUS system, characterized in that: include: S1, conduct geological assessment and obtain the storage area of carbon dioxide based on the assessment results; S2, configure absorbent suitable for the marine environment of the storage area; S3, creating a CO2 injection system to inject CO2 into offshore sandstone layers according to a layered injection strategy; S4, monitors the pressure changes during the injection process and issues an automatic warning when the pressure is abnormal.
2. The method for capturing and storing carbon dioxide in an offshore sandstone CCUS system according to claim 1, characterized in that: The S1 also includes evaluating the integrity of the geological structure and the leakage path.
3. The method for capturing and storing carbon dioxide in an offshore sandstone CCUS system according to claim 1, characterized in that: The active component of the absorbent includes an amine-containing compound, and the amine-containing compound includes one of diethanolamine and monoethanolamine.
4. The method for capturing and storing carbon dioxide in an offshore sandstone CCUS system according to claim 3, characterized in that: The S2 includes: S21, determining an absorbent formula, wherein the formula includes an active ingredient, an ionic liquid, a solid adsorbent, a salt-resistant agent, a temperature-resistant agent, and an alkaline buffer; S22, preparing sample formulas according to a preset ratio range to obtain different absorbent samples; S23, testing the absorbent sample, wherein the test includes a baseline test, a durability and adaptability test, and a regeneration ability test; S24, obtaining a final absorbent formula according to the test results.
5. The method for capturing and storing carbon dioxide in an offshore sandstone CCUS system according to claim 1, characterized in that: The S3 includes: S31, obtaining injection parameters of the injection well according to the geological structure and fluid dynamics simulation results; S32, adopts a layered injection strategy, increases the CO2 injection amount layer by layer, and injects the captured CO2 into the sandstone layer.
6. The method for capturing and storing carbon dioxide in an offshore sandstone CCUS system according to claim 5, characterized in that: The S4 includes: S41, monitors the injection parameters of the carbon dioxide injection process in real time through the installed pressure and temperature sensors, and adjusts the injection strategy according to the injection parameters; S42, regularly detects potential CO2 leaks and ground movement through seismic monitoring technology and ground deformation observations.
7. The method for capturing and storing carbon dioxide in an offshore sandstone CCUS system according to claim 1, characterized in that: The method further includes S5, conducting an environmental impact assessment, wherein the environmental impact assessment includes an ecotoxicity assessment, a biodegradability and accumulation assessment, and an environmental release assessment.
8. A CO2 capture and storage system in an offshore sandstone CCUS system, characterized by: The CO2 capture and storage method in an offshore sandstone CCUS system was used.