Marine diesel engine tail gas carbon dioxide capture low-energy-consumption safe storage method

Abstract

The invention belongs to the technical field of carbon dioxide capture low-energy-consumption safe storage methods, and discloses a marine diesel engine tail gas carbon dioxide capture low-energy-consumption safe storage method which comprises a carbon dioxide capture system, a low-energy-consumption system and a safe storage system. The carbon dioxide trapping system is mainly used for separating carbon dioxide from tail gas of a marine diesel engine for subsequent sealing or utilization, the carbon dioxide trapping system is divided into a pretreatment unit and a carbon trapping unit, and the carbon dioxide can be conveniently transported and sealed through liquefaction storage; the volume of the liquefied carbon dioxide is greatly reduced, long-distance transportation and storage are facilitated, the transportation cost is reduced, the liquefied carbon dioxide can also be used as a resource, for example, the liquefied carbon dioxide can be used in the fields of industrial raw materials, refrigerants, food preservation and the like, sustainable utilization of the resource is achieved, and the energy storage mode has the advantages of low cost, high efficiency, long service life and the like. And the energy utilization efficiency can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of low-energy consumption and safe storage methods for capturing carbon dioxide, and in particular to a low-energy consumption and safe storage method for capturing carbon dioxide from exhaust gas of ship diesel engines. Background Art

[0002] As global climate change becomes increasingly severe, reducing greenhouse gas emissions has become a consensus of the international community. As one of the important sources of carbon emissions, the shipping industry is facing tremendous pressure to reduce emissions. Ship diesel engine exhaust contains a large amount of carbon dioxide, and capturing this carbon dioxide is of great significance to reducing the carbon footprint of the shipping industry.

[0003] However, there are still some problems in the use of the existing low-energy consumption and safe storage method of carbon dioxide capture from ship diesel engine exhaust: There is a Chinese patent application number CN202211490444.9, a carbon dioxide storage method and system, which establishes a geological model of the carbon dioxide storage area and determines the carbon dioxide storage layer; captures carbon dioxide and passes through a pressurization module and a cooling module and then enters supercooled water to generate carbon dioxide hydrates. After the carbon dioxide hydrates are injected into a closed container, they are placed in the carbon dioxide storage layer, and a sensor is used to monitor the temperature of the carbon dioxide storage layer. When the monitored temperature exceeds a first threshold, the height of the closed container is adjusted so that the carbon dioxide hydrate is in a stable state. By generating carbon dioxide hydrates and sealing and placing them in a closed container, the stability of the exposed storage is improved. By simple parameter monitoring and position adjustment, the safety of the storage can be improved. The existing carbon dioxide storage method often requires the use of solvents in carbon dioxide capture, and the regeneration and disposal of the solvent may cause environmental pollution and increase costs.

[0004] To address the above problems, an innovative design was developed based on the existing low-energy consumption and safe storage method of carbon dioxide capture from ship diesel engine exhaust. Summary of the invention

[0005] The purpose of the present invention is to provide a low-energy consumption and safe storage method for capturing carbon dioxide from ship diesel engine exhaust, so as to solve the problem mentioned in the above background technology that the existing carbon dioxide storage methods often require the use of solvents in the capture of carbon dioxide, and the regeneration and disposal of the solvents may cause environmental pollution and increase costs.

[0006] To achieve the above object, the present invention provides the following technical solution: a method for capturing and storing carbon dioxide from ship diesel engine exhaust with low energy consumption and safety, comprising the following steps: S1. After the ship's diesel engine exhaust is discharged, it is collected by the carbon dioxide capture system. The carbon dioxide capture system pre-treats and captures the diesel engine exhaust from the ship. The main function of the carbon dioxide capture system is to separate carbon dioxide from the ship's diesel engine exhaust for subsequent storage or utilization; S2. Low-energy consumption systems for flue gas waste heat recovery and optimization of absorption and desorption equipment during carbon capture. Low-energy consumption systems mainly refer to a series of strategies and methods aimed at reducing carbon dioxide emissions and reducing energy consumption; S3. Finally, the carbon dioxide is liquefied, stored, sealed and monitored through a safe storage system. The safe storage system is a comprehensive system designed to ensure the safety and stability of carbon dioxide during the storage process.

[0007] Preferably, the pretreatment unit in step S1 uses a flue gas cooler to reduce the temperature of the flue gas so that it reaches the operating temperature range of the subsequent processing equipment. The flue gas cooler is usually composed of a shell, a piping system, a spray cleaning system, etc., and transfers the heat of the flue gas to the cooling medium through heat exchange, thereby achieving cooling.

[0008] Preferably, the carbon capture unit in step S1 includes an absorption stage and a recovery stage. The selectable absorbent on board is mainly an organic amine solution. In the absorption stage, the flue gas after dust removal enters the carbon dioxide absorption tower, and the flue gas flows from bottom to top, while the organic amine solution is sprayed down from the top of the tower. The two are in contact, and the carbon dioxide reacts with the organic amine solution in the absorption tower and is absorbed. The flue gas after partial carbon removal is discharged from the top of the tower.

[0009] Preferably, in the recovery stage of the carbon capture unit in step S1, after absorbing carbon dioxide, the used organic amine solution flows to the bottom of the tower, is pumped out of the absorption tower by a pump, and then flows through a heat exchanger to be sent to the recovery tower. In the recovery tower, the used organic amine solution is heated to a certain temperature and then releases carbon dioxide. The organic amine solution can reabsorb carbon dioxide, and the desorbed carbon dioxide is discharged from the top of the tower, compressed after drying and dehydration, and can be used for subsequent utilization and storage, and the regenerated organic amine solution is cooled by a heat exchanger and then sent back to the absorption tower for carbon dioxide cyclic absorption.

[0010] Preferably, the flue gas waste heat recovery in step S2 is performed by setting up a flue gas waste heat recovery device, such as a heat exchanger, to recover the exhaust heat of the ship's gas turbine to the maximum extent, to provide energy for the recovery process of carbon capture, thereby reducing energy consumption in the carbon capture process.

[0011] Preferably, the optimized absorption and recovery equipment in step S2 can significantly reduce the size and load of the carbon capture equipment and further reduce energy consumption by optimizing the structural design of the heat exchanger and the absorption tower and cooperating with a specific decarbonization absorbent. The absorption tower adopts a multi-stage spraying and packing structure to increase the contact area and contact time between carbon dioxide and the absorption liquid, thereby achieving efficient carbon dioxide capture.

[0012] Preferably, the liquefied storage in step S3 compresses, liquefies and purifies the separated carbon dioxide gas, and the liquefied carbon dioxide is transported to a storage container. Liquefied storage is not only convenient for transportation and long-term storage, but also reduces the storage space occupied. The storage tank is the main part of carbon dioxide storage, which is usually made of high-strength steel and equipped with an insulation layer to maintain the low temperature state of carbon dioxide. The liquefied carbon dioxide is stored under low temperature and high pressure conditions. This storage method has low storage costs, but has high requirements on the sealing of storage containers and pipelines.

[0013] Preferably, the sealing materials used for sealing and monitoring in step S3 include metals, such as steel and stainless steel, glass and special plastics, such as polytetrafluoroethylene PTFE. These materials can still maintain good sealing performance under high pressure and harsh environments. Using sealing gaskets or sealants at the sealing interfaces can increase the sealing performance of the interfaces.

[0014] Preferably, the parameters that need to be monitored for sealing and monitoring in step S3 include flow, pressure, liquid level, temperature, etc. Changes in these parameters can reflect the operating status of the storage system and the storage status of carbon dioxide. A complete monitoring system is established, including sensors, data acquisition devices, data processing and analysis systems, etc. Sensors should be installed in key positions to monitor parameter changes in the storage system in real time. The data acquisition device is responsible for transmitting the data collected by the sensor to the data processing and analysis system. The data processing and analysis system should process and analyze the collected data, detect abnormal data in time and issue early warnings. The introduction of remote monitoring and automatic control technology can realize remote monitoring and automatic control of the storage system.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: the low-energy consumption and safe storage method for capturing carbon dioxide from ship diesel engine exhaust gas allows carbon dioxide to be conveniently transported and sealed through liquefied storage, and the volume of liquefied carbon dioxide is greatly reduced, which is convenient for long-distance transportation and storage, thereby reducing transportation costs. Liquefied carbon dioxide can also be used as a resource, such as in the fields of industrial raw materials, refrigerants, and food preservation, thereby realizing sustainable utilization of resources. This energy storage method has the advantages of low cost, high efficiency, and long life, and helps to improve energy utilization efficiency.

[0016] 1. The low-energy consumption system can efficiently capture carbon dioxide from ship diesel engine exhaust emissions, thereby reducing greenhouse gas emissions, which is of great significance for mitigating global climate change and achieving carbon neutrality goals. In addition, the low-energy consumption system uses innovative membrane separation technology or chemical absorption technology to achieve a capture process without solvent loss, thereby eliminating the environmental pollution risks generated during the regeneration and disposal of solvents; 2. By monitoring the concentration and status of carbon dioxide, abnormal situations in the production process can be discovered in time, so that timely measures can be taken to deal with them, avoiding production interruptions and reduced efficiency. It can ensure that the carbon dioxide concentration in the workplace or living environment is within a safe range, thereby preventing health risks. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the process structure of the present invention. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] See also Figure 1 The present invention provides a technical solution: a method for capturing and storing carbon dioxide from ship diesel engine exhaust with low energy consumption and safety, comprising the following steps: S1. After the ship's diesel engine exhaust is discharged, it is collected by the carbon dioxide capture system. The carbon dioxide capture system pre-treats and captures the diesel engine exhaust from the ship. The main function of the carbon dioxide capture system is to separate carbon dioxide from the ship's diesel engine exhaust for subsequent storage or utilization; S2. Low-energy consumption systems for flue gas waste heat recovery and optimization of absorption and desorption equipment during carbon capture. Low-energy consumption systems mainly refer to a series of strategies and methods aimed at reducing carbon dioxide emissions and reducing energy consumption; S3. Finally, the carbon dioxide is liquefied, stored, sealed and monitored through a safe storage system. The safe storage system is a comprehensive system designed to ensure the safety and stability of carbon dioxide during the storage process.

[0020] The pretreatment unit in step S1 uses a flue gas cooler to reduce the temperature of the flue gas to reach the operating temperature range of the subsequent treatment equipment. The flue gas cooler is usually composed of a shell, a piping system, and a spray cleaning system. The heat of the flue gas is transferred to the cooling medium by heat exchange, thereby achieving cooling.

[0021] The carbon capture unit in step S1 includes an absorption stage and a recovery stage. The absorbent that can be selected on board is mainly an organic amine solution. In the absorption stage, the flue gas after dust removal enters the carbon dioxide absorption tower, and the flue gas flows from bottom to top, while the organic amine solution is sprayed down from the top of the tower. The two come into contact, and the carbon dioxide reacts with the organic amine solution in the absorption tower and is absorbed. The flue gas after partial carbon removal is discharged from the top of the tower.

[0022] In the recovery stage of the carbon capture unit in step S1, after absorbing carbon dioxide, the used organic amine solution flows to the bottom of the tower, is pumped out of the absorption tower by a pump, and then flows through a heat exchanger to be sent to the recovery tower. In the recovery tower, the used organic amine solution is heated to a certain temperature and then releases carbon dioxide. The organic amine solution can reabsorb carbon dioxide, and the desorbed carbon dioxide is discharged from the top of the tower, compressed after drying and dehydration, and can be used for subsequent utilization and storage. The regenerated organic amine solution is cooled by a heat exchanger and then sent back to the absorption tower for cyclic absorption of carbon dioxide.

[0023] The flue gas waste heat recovery in step S2 is achieved by setting up a flue gas waste heat recovery device, such as a heat exchanger, to recover the exhaust heat of the ship's gas turbine to the maximum extent, and provide energy for the recovery process of carbon capture, thereby reducing energy consumption in the carbon capture process.

[0024] The optimized absorption and recovery equipment in step S2 can significantly reduce the size and load of the carbon capture equipment and further reduce energy consumption by optimizing the structural design of the heat exchanger and the absorption tower and cooperating with a specific decarbonization absorbent. The absorption tower adopts a multi-stage spraying and packing structure to increase the contact area and contact time between carbon dioxide and the absorption liquid, thereby achieving efficient carbon dioxide capture.

[0025] The liquefied storage in step S3 compresses, liquefies and purifies the separated carbon dioxide gas, and the liquefied carbon dioxide is transported to the storage container. The liquefied storage is not only convenient for transportation and long-term storage, but also reduces the storage space occupied. The storage tank is the main part of the carbon dioxide storage, which is usually made of high-strength steel and equipped with an insulation layer to maintain the low temperature state of the carbon dioxide. The liquefied carbon dioxide is stored under low temperature and high pressure conditions. This storage method has low storage costs, but has high requirements on the sealing of storage containers and pipelines.

[0026] The sealing materials used for sealing and monitoring in step S3 include metals, such as steel and stainless steel, glass and special plastics, such as polytetrafluoroethylene (PTFE). These materials can still maintain good sealing performance under high pressure and harsh environments. Using sealing gaskets or sealants at the sealing interface can increase the sealing performance of the interface.

[0027] The parameters that need to be monitored for sealing and monitoring in step S3 include flow, pressure, liquid level, temperature, etc. The changes in these parameters can reflect the operating status of the storage system and the storage situation of carbon dioxide. A complete monitoring system is established, including sensors, data acquisition devices, data processing and analysis systems, etc. Sensors should be installed in key positions to monitor parameter changes in the storage system in real time. The data acquisition device is responsible for transmitting the data collected by the sensor to the data processing and analysis system. The data processing and analysis system should process and analyze the collected data, detect abnormal data in time and issue early warnings. The introduction of remote monitoring and automatic control technology can realize remote monitoring and automatic control of the storage system.

[0028] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in the field. Although the embodiments of the present invention have been shown and described, it is understood by ordinary technicians in the field that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for capturing and storing carbon dioxide from diesel engine exhaust with low energy consumption and safety, comprising the following steps: S1. After the ship's diesel engine exhaust is discharged, it is collected by the carbon dioxide capture system. The carbon dioxide capture system pre-treats and captures the diesel engine exhaust from the ship. The main function of the carbon dioxide capture system is to separate carbon dioxide from the ship's diesel engine exhaust for subsequent storage or utilization; S2. Low-energy consumption systems for flue gas waste heat recovery and optimization of absorption and desorption equipment during carbon capture. Low-energy consumption systems mainly refer to a series of strategies and methods aimed at reducing carbon dioxide emissions and reducing energy consumption; S3. Finally, the carbon dioxide is liquefied, stored, sealed and monitored through a safe storage system. The safe storage system is a comprehensive system designed to ensure the safety and stability of carbon dioxide during the storage process.

2. A method for capturing and storing carbon dioxide from ship diesel engine exhaust with low energy consumption and safety according to claim 1, characterized in that: The pretreatment unit in step S1 uses a flue gas cooler to reduce the temperature of the flue gas to reach the operating temperature range of the subsequent treatment equipment. The flue gas cooler is usually composed of a shell, a piping system, and a spray cleaning system. The heat of the flue gas is transferred to the cooling medium by heat exchange, thereby achieving cooling.

3. A method for capturing and storing carbon dioxide from ship diesel engine exhaust with low energy consumption and safety according to claim 1, characterized in that: The carbon capture unit in step S1 includes an absorption stage and a recovery stage. The absorbent that can be selected on board is mainly an organic amine solution. In the absorption stage, the flue gas after dust removal enters the carbon dioxide absorption tower, and the flue gas flows from bottom to top, while the organic amine solution is sprayed down from the top of the tower. The two come into contact, and the carbon dioxide reacts with the organic amine solution in the absorption tower and is absorbed. The flue gas after partial carbon removal is discharged from the top of the tower.

4. A method for capturing and storing carbon dioxide from ship diesel engine exhaust with low energy consumption and safety according to claim 1, characterized in that: In the recovery stage of the carbon capture unit in step S1, after absorbing carbon dioxide, the used organic amine solution flows to the bottom of the tower, is pumped out of the absorption tower by a pump, and then flows through a heat exchanger to be sent to the recovery tower. In the recovery tower, the used organic amine solution is heated to a certain temperature and then releases carbon dioxide. The organic amine solution can reabsorb carbon dioxide, and the desorbed carbon dioxide is discharged from the top of the tower, compressed after drying and dehydration, and can be used for subsequent utilization and storage. The regenerated organic amine solution is cooled by a heat exchanger and then sent back to the absorption tower for cyclic absorption of carbon dioxide.

5. A method for capturing and storing carbon dioxide from ship diesel engine exhaust with low energy consumption and safety according to claim 1, characterized in that: The flue gas waste heat recovery in step S2 is achieved by setting up a flue gas waste heat recovery device, such as a heat exchanger, to recover the exhaust heat of the ship's gas turbine to the maximum extent, and provide energy for the recovery process of carbon capture, thereby reducing energy consumption in the carbon capture process.

6. A method for capturing and storing carbon dioxide from ship diesel engine exhaust with low energy consumption and safety according to claim 5, characterized in that: The optimized absorption and recovery equipment in step S2 can significantly reduce the size and load of the carbon capture equipment and further reduce energy consumption by optimizing the structural design of the heat exchanger and the absorption tower and cooperating with a specific decarbonization absorbent. The absorption tower adopts a multi-stage spraying and packing structure to increase the contact area and contact time between carbon dioxide and the absorption liquid, thereby achieving efficient carbon dioxide capture.

7. A method for capturing and storing carbon dioxide from ship diesel engine exhaust with low energy consumption and safety according to claim 1, characterized in that: The liquefied storage in step S3 compresses, liquefies and purifies the separated carbon dioxide gas, and the liquefied carbon dioxide is transported to the storage container. The liquefied storage is not only convenient for transportation and long-term storage, but also reduces the storage space occupied. The storage tank is the main part of the carbon dioxide storage, which is usually made of high-strength steel and equipped with an insulation layer to maintain the low temperature state of the carbon dioxide. The liquefied carbon dioxide is stored under low temperature and high pressure conditions. This storage method has low storage costs, but has high requirements on the sealing of storage containers and pipelines.

8. A method for capturing and storing carbon dioxide from ship diesel engine exhaust with low energy consumption and safety according to claim 1, characterized in that: The sealing materials used for sealing and monitoring in step S3 include metals, such as steel and stainless steel, glass and special plastics, such as polytetrafluoroethylene (PTFE). These materials can still maintain good sealing performance under high pressure and harsh environments. Using sealing gaskets or sealants at the sealing interface can increase the sealing performance of the interface.

9. A method for capturing and storing carbon dioxide from ship diesel engine exhaust with low energy consumption and safety according to claim 8, characterized in that: The parameters that need to be monitored for sealing and monitoring in step S3 include flow, pressure, liquid level, temperature, etc. The changes in these parameters can reflect the operating status of the storage system and the storage situation of carbon dioxide. A complete monitoring system is established, including sensors, data acquisition devices, data processing and analysis systems, etc. Sensors should be installed in key positions to monitor parameter changes in the storage system in real time. The data acquisition device is responsible for transmitting the data collected by the sensor to the data processing and analysis system. The data processing and analysis system should process and analyze the collected data, detect abnormal data in time and issue early warnings. The introduction of remote monitoring and automatic control technology can realize remote monitoring and automatic control of the storage system.

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