Multi-stage washing and storing system for discharged ammonia gas of ammonia fuel supply system

Abstract

The invention relates to a multi-stage washing and storing system for ammonia gas discharged by a marine engine, which comprises a first-stage pressurized ammonia gas washing device, a second-stage pressurized ammonia gas washing device, a back pressure valve, a normal-pressure ammonia gas washing device and an ammonia water collecting tank, the device comprises a pressurized ammonia gas washing cabinet, a first-stage ammonia water pump and a first-stage ammonia water cooler, the second-stage pressurized ammonia gas washing device is used for further deep washing and comprises a spray tower, and a plurality of layers of fillers and adjustable spray heads are arranged in the spray tower, so that gas-liquid contact is enhanced; the back pressure valve reduces the pressure of the ammonia gas to normal pressure for final treatment of the normal-pressure washing device; the ammonia water collecting tank collects and stores ammonia water generated by washing, and a built-in liquid level and concentration sensor monitors in real time. By means of multi-stage washing and accurate control, ammonia gas is efficiently treated, it is ensured that emission reaches the standard, an efficient, environment-friendly and intelligent solution can be provided, the method has important application value and popularization prospects, green development of the ship industry is promoted, and environmental pollution is reduced.

Description

Technical Field

[0001] The invention belongs to the field of marine engines, and in particular relates to a multi-stage washing storage system for releasing ammonia from an ammonia fuel supply system. Background Art

[0002] With the increasing global awareness of environmental protection and the goal of net zero greenhouse gas emissions by 2050 proposed by the International Maritime Organization (IMO), the shipping industry is facing tremendous pressure to reduce emissions. Ammonia fuel, as a low-carbon, environmentally friendly alternative fuel, has gradually attracted the attention of the shipping industry because its combustion products are mainly nitrogen and water, and it produces almost no greenhouse gas emissions. In addition, ammonia has a wide range of sources. It can be produced from renewable energy (such as wind power and solar energy) to produce hydrogen, and then synthesize green ammonia with nitrogen in the air, which makes ammonia fuel have significant advantages in sustainable development.

[0003] However, the application of ammonia fuel is not without challenges. In the ammonia fuel supply system of the ship's main engine, the safe storage, transportation and discharge treatment of ammonia is one of the key technical difficulties. Especially in a pressurized environment, how to effectively deal with the ammonia that may be leaked from the ammonia fuel supply system and its auxiliary systems to meet strict emission standards has become a key factor restricting the widespread application of ammonia fuel in the shipping industry. Traditional ammonia treatment methods often have problems such as low treatment efficiency, high treatment costs and possible secondary pollution, and cannot meet the high requirements of the shipping industry for ammonia treatment. Summary of the invention

[0004] In order to overcome the above-mentioned deficiencies of the prior art, the present invention provides a multi-stage washing and storage system for ammonia gas released from an ammonia fuel supply system. The ammonia gas released from the ammonia fuel supply system and its auxiliary systems during operation can be effectively treated through multi-stage washing treatment under a pressurized environment to ensure that its emission concentration meets environmental protection standards.

[0005] The technical solution of the present invention is as follows:

[0006] A multi-stage scrubbing and storage system for ammonia released from a marine engine, characterized in that it comprises:

[0007] A first-stage pressurized ammonia scrubbing device comprises a pressurized ammonia scrubbing cabinet (1), a first-stage ammonia water pump (7) and a first-stage ammonia water cooler (10), wherein the pressurized ammonia scrubbing cabinet (1) is used to preliminarily receive and scrub pressurized ammonia discharged from a gas supply system, the first-stage ammonia water pump (7) is used to extract ammonia water from the bottom of the scrubbing cabinet and recycle it, and the first-stage ammonia water cooler (10) is used to reduce the temperature of ammonia water to prevent the solubility from decreasing;

[0008] A two-stage pressurized ammonia scrubbing device comprises a pressurized ammonia scrubbing cabinet (2), a spray tower (6), a two-stage ammonia water pump (8) and a two-stage ammonia water cooler (11), which further performs deep scrubbing on the ammonia gas. The spray tower (6) is provided with a multi-layer filler and a plurality of adjustable spray heads to form a multi-layer spray structure to increase the gas-liquid contact area and prolong the contact time.

[0009] A back pressure valve (3), located after the two-stage pressurized ammonia scrubbing device, is used to reduce the pressure of the ammonia that has undergone two-stage pressurized scrubbing to normal pressure;

[0010] The atmospheric pressure ammonia gas washing device comprises an atmospheric pressure ammonia gas washing cabinet (4) and an ammonia water pump (9), and is used for performing final washing on the ammonia gas whose pressure has been reduced to ensure that the ammonia gas concentration meets the emission standard;

[0011] The ammonia water collection tank (5) is used to collect and store the ammonia water generated during the washing process. A liquid level sensor and a concentration sensor are provided inside the tank to monitor the liquid level and concentration of the ammonia water in real time, and when the concentration of the ammonia water reaches a certain value, a discharge device is automatically started to discharge the ammonia water into a designated collection system or for reuse.

[0012] Furthermore, the first-stage pressurized ammonia scrubbing cabinet (1) and the second-stage pressurized ammonia scrubbing cabinet (2) are both provided with a plurality of spray heads and evenly distributed fillers to increase the contact area between ammonia gas and ammonia water and improve the scrubbing efficiency; at the same time, pressure sensors and temperature sensors are also provided inside to monitor the pressure and temperature during the scrubbing process in real time.

[0013] Furthermore, the primary ammonia water pump (7) and the secondary ammonia water pump (8) are both made of highly corrosion-resistant materials to ensure that they can maintain good pumping performance even when in contact with ammonia water for a long time; and the flow rate and lift of the ammonia water pump can be adjusted according to actual needs to meet the needs of different washing stages.

[0014] Furthermore, the primary ammonia water cooler (10) and the secondary ammonia water cooler (11) both use high-efficiency heat exchange technology to circulate and cool the ammonia water to a suitable temperature range to prevent the solubility from being reduced due to heat release during the dissolution process; and temperature sensors and flow sensors are provided inside the coolers to monitor the cooling effect and the ammonia water flow in real time.

[0015] Furthermore, the filler of the spray tower (6) is made of a material with a high specific surface area to increase the gas-liquid contact area and prolong the contact time; and the spray head is adjustable to adjust the spray volume and spray angle according to actual needs.

[0016] Furthermore, the back pressure valve (3) adopts a high-precision regulating valve, which can accurately control the pressure reduction process of the ammonia gas, ensuring that the pressure of the ammonia gas after pressure reduction is stable and meets the requirements of subsequent processing.

[0017] Furthermore, the ammonia water collecting tank (5) is designed with a large capacity to ensure that sufficient ammonia water can be collected and stored for subsequent treatment or reuse.

[0018] Furthermore, it also includes a control system for real-time monitoring and controlling various parameters in the washing process, including pressure, temperature, concentration, and automatically adjusting the parameters of the washing device according to actual needs, including spray volume and cooling temperature.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1) The present invention can significantly reduce the concentration of ammonia discharged from marine engines through multi-stage washing treatment. In the primary and secondary pressure washing devices, ammonia is fully contacted with ammonia water and chemically reacts to convert ammonia into harmless nitrogen and water. At the same time, the atmospheric pressure washing device serves as the last line of defense to further ensure that the concentration of ammonia after washing meets environmental protection requirements. The concentration of ammonia emissions after treatment by this system is much lower than the relevant regulatory standards, effectively reducing pollution to the atmospheric environment.

[0021] 2) The present invention not only focuses on the treatment effect of ammonia, but also pays attention to the utilization efficiency of resources. In the washing process, ammonia water is recycled, reducing the waste of water resources. At the same time, the treated ammonia water can also be used in other industrial processes or as fertilizer, realizing the reuse of resources and circular economy.

[0022] 3) It uses advanced automatic control technology and sensor monitoring technology, which can monitor various parameters (such as pressure, temperature, concentration, etc.) in the washing process in real time, and automatically adjust the parameters of the washing device (such as spray volume, cooling temperature, etc.) according to actual needs. This intelligent control method not only improves the stability and reliability of the system, but also reduces the difficulty and cost of manual operation. 4) BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of a multi-stage scrubbing storage system for releasing ammonia gas from an ammonia fuel supply system according to the present invention. DETAILED DESCRIPTION

[0025] The technical solution of the present invention is described in detail below in conjunction with the accompanying drawings and embodiments, but this should not limit the protection scope of the present invention.

[0026] The present embodiment provides a multi-stage washing and storage system for ammonia released from a marine engine, which is intended to effectively treat ammonia released from an ammonia fuel supply system and its auxiliary systems during operation, and ensure that it can meet emission standards after multi-stage washing treatment under a pressurized environment, including a first-stage pressurized ammonia washing device, a second-stage pressurized ammonia washing device, a back pressure valve 3, a normal-pressure ammonia washing device and an ammonia water collecting tank 5.

[0027] The primary pressurized ammonia scrubbing device comprises a pressurized ammonia scrubbing cabinet 1, a primary ammonia water pump 7 and a primary ammonia water cooler 10. The pressurized ammonia scrubbing cabinet 1 is used to initially receive and scrub the pressurized ammonia gas discharged from the gas supply system. The primary ammonia water pump 7 is responsible for extracting the ammonia water from the bottom of the scrubbing cabinet and recycling it to improve the scrubbing efficiency. The primary ammonia water cooler 10 is used to reduce the temperature of the ammonia water to prevent the solubility from being reduced due to the heat release during the dissolution process.

[0028] In the present embodiment, the pressurized ammonia washing cabinet 1 is provided with a plurality of spray heads and evenly distributed fillers to increase the contact area between ammonia and ammonia water and improve the washing efficiency. At the same time, a pressure sensor and a temperature sensor are also provided inside to monitor the pressure and temperature during the washing process in real time to ensure the washing effect. The ammonia pump 7 is made of highly corrosion-resistant materials to ensure that it can maintain good pumping performance even in the case of long-term contact with ammonia water. The flow rate and head of the ammonia pump can be adjusted according to actual needs to meet the needs of different washing stages. The ammonia cooler 10 adopts efficient heat exchange technology to circulate and cool the ammonia water to a suitable temperature range to prevent the solubility from being reduced due to heat release during the dissolution process. A temperature sensor and a flow sensor are provided inside the cooler to monitor the cooling effect and ammonia flow in real time.

[0029] The secondary pressurized ammonia washing device includes a pressurized ammonia washing cabinet 2, a spray tower 6, a secondary ammonia water pump 8 and a secondary ammonia water cooler 11. Similar to the primary device, the secondary device further performs deep washing of the ammonia. In particular, the spray tower 6 is provided with multiple layers of fillers and multiple spray heads to form a multi-layer spray structure. The fillers are made of materials with high specific surface area to increase the gas-liquid contact area and extend the contact time. The spray head is adjustable, and the spray amount and spray angle can be adjusted according to actual needs. The secondary ammonia water pump 8 and the secondary ammonia water cooler 11 are the same as those in the primary washing device, but the parameters may vary according to the washing needs.

[0030] The back pressure valve 3 is located after the two-stage pressurized ammonia scrubbing device and is used to reduce the pressure of the ammonia after the two-stage pressurized scrubbing to normal pressure so that it can enter the normal pressure ammonia scrubbing device for treatment. This embodiment uses a high-precision regulating valve to accurately control the pressure reduction process of ammonia, ensuring that the pressure of the ammonia after pressure reduction is stable and meets the requirements of subsequent treatment.

[0031] The atmospheric pressure ammonia scrubbing device comprises an atmospheric pressure ammonia scrubbing cabinet 4 and an ammonia water pump 9, which are used to perform final scrubbing on the depressurized ammonia to ensure that the ammonia concentration reaches the emission standard.

[0032] Ammonia collection tank 5: It is used to collect and store ammonia produced during the washing process for subsequent treatment or reuse. It adopts a large-capacity design and is equipped with a liquid level sensor and a concentration sensor to monitor the liquid level and concentration of ammonia in real time. When the concentration of ammonia reaches a certain value, the discharge device is automatically activated to discharge it into a designated collection system or for reuse.

[0033] The working principle of the present invention is as follows:

[0034] Pressurized washing process: The pressurized ammonia discharged from the gas supply system first enters the first-stage pressurized ammonia washing device, and is fully contacted with the circulating ammonia water in the pressurized ammonia washing cabinet 1 for preliminary washing. The optimized layout of the spray head and filler greatly increases the contact area between the ammonia and the ammonia water, improving the washing efficiency. Subsequently, the ammonia enters the second-stage pressurized ammonia washing device, and is further washed in the pressurized ammonia washing cabinet 2 and the spray tower 6. The multi-layer spray structure and filler in the spray tower prolong the contact time between the ammonia and the ammonia water, further reducing the ammonia concentration.

[0035] Pressure reduction and normal pressure washing: After two-stage pressure washing, the ammonia gas is reduced to normal pressure through the back pressure valve 3, and then enters the normal pressure ammonia washing device, and is finally washed in the normal pressure ammonia washing cabinet 4. The filler and spray head in the washing cabinet wash the ammonia gas again to ensure that the ammonia concentration meets the emission standards.

[0036] Concentration detection and emission: The ammonia gas after washing is tested for concentration. If it meets the emission standards, it can be discharged directly into the atmosphere. If it does not meet the standards, it needs to be returned to the washing system for further treatment.

[0037] Ammonia cooling and collection: During the washing process, the heat released by ammonia dissolution will cause the temperature of ammonia to rise, thereby reducing its solubility. To this end, each pressurized ammonia washing cabinet is equipped with an ammonia cooler, which pumps ammonia water for circulating cooling through an ammonia pump. When the ammonia concentration reaches a certain value, it is discharged into the ammonia collection tank 5 for storage.

[0038] System configuration and optimization

[0039] Adjustment of the number of pressurized washing devices: According to the amount of ammonia and the different standards for the concentration of ammonia discharged, the number of pressurized ammonia washing devices can be flexibly increased or decreased to meet different washing requirements. For example, when the amount of ammonia is large or the discharge concentration requirement is high, the number of washing devices can be increased to improve the washing efficiency; conversely, the number of washing devices can be reduced to reduce costs and floor space.

[0040] Spatial layout: According to the actual site size, the pressurized ammonia scrubber 1, the pressurized ammonia scrubber 2 and the normal-pressure ammonia scrubber 4 can be placed separately, or they can be integrated into the same scrubber and partitioned by physical separation to save space and improve equipment utilization.

[0041] Intelligent control and monitoring: In order to further improve the stability and reliability of the system, an intelligent control and monitoring system can be introduced. The system can monitor various parameters in the washing process (such as pressure, temperature, concentration, etc.) in real time, and automatically adjust the parameters of the washing device (such as spray volume, cooling temperature, etc.) according to actual needs. At the same time, an alarm system can also be set to deal with possible abnormal situations.

[0042] In summary, the multi-stage washing and storage system for ammonia released from a marine engine provided by the present invention and its application method effectively reduce the ammonia emission concentration and meet environmental protection requirements by combining multi-stage pressurized washing and normal pressure washing. At the same time, the system has flexible configuration, high space utilization, and intelligent control and monitoring functions, and has high practical value and application prospects.

Claims

1. A multi-stage scrubbing and storage system for ammonia released from a marine engine, characterized in that: include: A first-stage pressurized ammonia scrubbing device comprises a pressurized ammonia scrubbing cabinet (1), a first-stage ammonia water pump (7) and a first-stage ammonia water cooler (10), wherein the pressurized ammonia scrubbing cabinet (1) is used to preliminarily receive and scrub pressurized ammonia discharged from a gas supply system, the first-stage ammonia water pump (7) is used to extract ammonia water from the bottom of the scrubbing cabinet and recycle it, and the first-stage ammonia water cooler (10) is used to reduce the temperature of ammonia water to prevent the solubility from decreasing; A two-stage pressurized ammonia scrubbing device comprises a pressurized ammonia scrubbing cabinet (2), a spray tower (6), a two-stage ammonia water pump (8) and a two-stage ammonia water cooler (11), which further performs deep scrubbing on the ammonia gas. The spray tower (6) is provided with a multi-layer filler and a plurality of adjustable spray heads to form a multi-layer spray structure to increase the gas-liquid contact area and prolong the contact time. A back pressure valve (3), located after the two-stage pressurized ammonia scrubbing device, is used to reduce the pressure of the ammonia that has undergone two-stage pressurized scrubbing to normal pressure; The atmospheric pressure ammonia gas washing device comprises an atmospheric pressure ammonia gas washing cabinet (4) and an ammonia water pump (9), and is used for performing final washing on the ammonia gas whose pressure has been reduced to ensure that the ammonia gas concentration meets the emission standard; The ammonia water collection tank (5) is used to collect and store the ammonia water generated during the washing process. A liquid level sensor and a concentration sensor are provided inside the tank to monitor the liquid level and concentration of the ammonia water in real time, and when the concentration of the ammonia water reaches a certain value, a discharge device is automatically started to discharge the ammonia water into a designated collection system or for reuse.

2. The multi-stage scrubbing and storage system for ammonia released from a marine engine according to claim 1, characterized in that: The first-stage pressurized ammonia washing cabinet (1) and the second-stage pressurized ammonia washing cabinet (2) are both provided with a plurality of spray heads and evenly distributed fillers to increase the contact area between ammonia gas and ammonia water and improve the washing efficiency; at the same time, pressure sensors and temperature sensors are also provided inside to monitor the pressure and temperature in real time during the washing process.

3. The multi-stage scrubbing and storage system for ammonia released from a marine engine according to claim 1, characterized in that: The primary ammonia water pump (7) and the secondary ammonia water pump (8) are both made of highly corrosion-resistant materials to ensure that they can maintain good pumping performance even when in contact with ammonia water for a long time; and the flow rate and lift of the ammonia water pump can be adjusted according to actual needs to meet the needs of different washing stages.

4. The multi-stage scrubbing and storage system for ammonia released from a marine engine according to claim 1, characterized in that: The primary ammonia water cooler (10) and the secondary ammonia water cooler (11) both use high-efficiency heat exchange technology to circulate and cool the ammonia water to a suitable temperature range to prevent the solubility from being reduced due to heat release during the dissolution process; and temperature sensors and flow sensors are provided inside the coolers to monitor the cooling effect and the ammonia water flow in real time.

5. The multi-stage scrubbing and storage system for ammonia released from a marine engine according to claim 1, characterized in that: The filler of the spray tower (6) is made of a material with a high specific surface area to increase the gas-liquid contact area and prolong the contact time; and the spray head is adjustable, and the spray volume and spray angle can be adjusted according to actual needs.

6. The multi-stage scrubbing and storage system for ammonia released from a marine engine according to claim 1, characterized in that: The back pressure valve (3) adopts a high-precision regulating valve, which can accurately control the pressure reduction process of the ammonia gas, thereby ensuring that the pressure of the ammonia gas after pressure reduction is stable and meets the requirements of subsequent processing.

7. The multi-stage scrubbing and storage system for ammonia released from a marine engine according to claim 1, characterized in that: The ammonia water collection tank (5) is designed with a large capacity to ensure that sufficient ammonia water can be collected and stored for subsequent treatment or reuse.

8. The multi-stage scrubbing and storage system for ammonia released from a marine engine according to any one of claims 1 to 7, characterized in that: It also includes a control system for real-time monitoring and control of various parameters in the washing process, including pressure, temperature, and concentration, and automatically adjusting the parameters of the washing device according to actual needs, including spray volume and cooling temperature.

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