An integrated ship exhaust gas treatment system and a ship exhaust gas treatment process

Abstract

The present invention discloses a comprehensive ship exhaust gas treatment system and a ship exhaust gas treatment process, which include an engine flue gas treatment subsystem and a cabin exhaust gas treatment subsystem; the engine flue gas treatment subsystem includes an ozone generator, a flue gas-ozone mixer, a first catalytic oxidation reactor, and a first flue gas discharge pipeline; the flue gas-ozone mixer is connected to an engine flue gas discharge pipeline; the cabin exhaust gas treatment subsystem includes a burner, a second catalytic oxidation reactor, and a second flue gas discharge pipeline; the input end of the burner is respectively connected to an air intake pipeline and a discharged exhaust gas discharge pipeline; the input end of the second catalytic oxidation reactor is connected to a ventilation exhaust gas discharge pipeline; the ventilation exhaust gas discharge pipeline is connected to the output end of the ozone generator, and an exhaust gas-ozone mixer is arranged on the ventilation exhaust gas discharge pipeline. Through the above settings, the present invention can achieve comprehensive coverage and comprehensive treatment of ship exhaust gas, and realize the efficient utilization of resources.

Description

Technical Field

[0001] The present invention relates to the field of ship exhaust gas treatment, and particularly to a comprehensive ship exhaust gas treatment system and a ship exhaust gas treatment process. Background Art

[0002] In the process of the global energy structure accelerating the transformation to clean energy, as an efficient and clean energy, the maritime transportation demand for LNG (liquefied natural gas) has increased sharply, and LNG carriers have become the key link in energy transportation. However, while LNG carriers contribute to energy transportation, the problem of exhaust gas emissions during their operation has gradually emerged.

[0003] Firstly, in response to the requirements of energy conservation and emission reduction to reduce pollutant emissions brought by traditional fuels, most current LNG carriers adopt dual-fuel (i.e., diesel mixed with LNG as fuel, mainly composed of methane or ammonia) engines. However, in actual operation, due to the complexity of the combustion process and the influence of various working conditions, about 3-7% of methane or ammonia will escape due to incomplete combustion. The greenhouse effect intensity of methane is about 28-36 times that of carbon dioxide. A large amount of methane escaping into the atmosphere will greatly exacerbate the trend of global warming.

[0004] Currently, for the methane and ammonia escaping from the flue gas of LNG carrier engines, the conventional treatment method is catalytic oxidation treatment. However, since the catalytic oxidation reaction usually needs to be effectively carried out in the temperature range of 300°C - 400°C, and the flue gas temperature discharged from LNG carrier engines is generally in the range of 200°C - 300°C. Therefore, to meet the requirements of catalytic oxidation treatment, additional heating equipment such as burners or electric heaters is often needed to increase the flue gas temperature. However, this method not only greatly increases the energy consumption and operation cost of the ship, but also makes the equipment system more complex and occupies the limited space on the ship. Moreover, during the operation of the ship, due to combustion reasons, the engine flue gas inevitably contains oil stains, dust or other impurities, which are extremely likely to adhere to the surface of the catalyst, causing the catalyst to be poisoned and inactivated, affecting the effect of catalytic oxidation, and thus resulting in the situation that the exhaust gas treatment does not meet the environmental protection standards.

[0005] Secondly, when treating the ventilation exhaust gas of LNG carriers, a regenerative thermal oxidation (RTO) device is usually used to achieve this. However, this method also has certain drawbacks. Specifically, due to the huge discharge amount of the ventilation exhaust gas of LNG carriers and the low concentration of combustible gas, it cannot be directly burned, and additional gas needs to be supplemented to maintain the oxidation decomposition temperature of about 700°C of the RTO device. Therefore, the fuel cost will increase. In addition, due to the large volume and complex structure of the RTO device, it requires a large installation space and complex supporting facilities, making it difficult to be reasonably installed and set in the limited space on the ship.

[0006] Finally, during the loading, unloading, and storage of LNG on an LNG ship, due to the change in pressure within the storage tank, in order to avoid equipment damage, vent gases are also generated. The main components of these vent gases are high-purity methane or ammonia. Currently, these vent gases are usually directly discharged into the atmosphere without being fully utilized, resulting in a waste of resources.

[0007] Therefore, a ship exhaust gas comprehensive treatment system and a ship exhaust gas treatment process are needed to solve the above problems. Summary of the Invention

[0008] The purpose of the present invention is to provide a ship exhaust gas comprehensive treatment system and a ship exhaust gas treatment process to achieve comprehensive coverage and comprehensive treatment of ship exhaust gas, realize efficient utilization of resources, and compared with the method of separately configuring treatment equipment for different exhaust gases in the prior art, can effectively reduce the space occupied by the equipment on the ship, achieving the purpose of improving the space utilization rate of the ship.

[0009] To solve the above technical problems, the present invention provides a ship exhaust gas comprehensive treatment system, including an engine flue gas treatment subsystem and a cabin exhaust gas treatment subsystem;

[0010] The engine flue gas treatment subsystem includes an ozone generator, a flue gas-ozone mixer, a first catalytic oxidation reactor, and a first flue gas discharge pipeline connected in sequence;

[0011] The input end of the flue gas-ozone mixer is connected to an engine flue gas discharge pipeline;

[0012] The cabin exhaust gas treatment subsystem includes a burner, a second catalytic oxidation reactor, and a second flue gas discharge pipeline connected in sequence;

[0013] The input end of the burner is respectively connected to an air inlet pipeline and a vent gas discharge pipeline;

[0014] The input end of the second catalytic oxidation reactor is connected to a ventilation exhaust gas discharge pipeline;

[0015] Among them, the ventilation exhaust gas discharge pipeline is connected to the output end of the ozone generator through a branch pipeline, and an exhaust gas-ozone mixer is provided on the ventilation exhaust gas discharge pipeline.

[0016] Further, the second flue gas discharge pipeline is connected to the engine flue gas discharge pipeline through a first valve pipeline to increase the mixing reaction temperature of the engine flue gas and ozone in the flue gas-ozone mixer.

[0017] Further, the engine flue gas treatment subsystem further includes an analysis exhaust gas pipeline;

[0018] One end of the analyzed waste gas pipeline is connected to the ship PSA nitrogen generator, and the other end is connected to the ozone generator, which is used to provide a gas raw material source for the ozone generated by the ozone generator.

[0019] Furthermore, a gas concentration detection sensor is arranged at the input end of the first catalytic oxidation reactor to detect the concentration of ammonia or methane.

[0020] A bypass pipeline is connected between the flue gas-ozone mixer and the first flue gas discharge pipeline, which is used to selectively bypass or pass the gas output by the flue gas-ozone mixer through the first catalytic oxidation reactor according to the concentration detected by the gas concentration detection sensor.

[0021] Furthermore, both the first catalytic oxidation reactor and the second catalytic oxidation reactor are internally filled with catalyst fillers.

[0022] The catalyst filler is one or more of copper oxide, manganese oxide, and titanium dioxide.

[0023] Furthermore, it also includes a catalyst activation steam pipeline.

[0024] The output end of the catalyst activation steam pipeline is connected to the engine flue gas discharge pipeline and the ventilation waste gas discharge pipeline through a second valve pipeline, which is respectively used to clean the carbon deposits formed by the flue gas in the engine flue gas discharge pipeline and to purge the burner connected to the ventilation waste gas discharge pipeline.

[0025] Furthermore, a heat exchange tube for recovering the waste heat of the incinerated flue gas is arranged inside the second catalytic oxidation reactor.

[0026] Furthermore, the ozone generator is a tubular arc ozone generator.

[0027] Furthermore, a pressure stabilizing valve is arranged on the discharge pipeline of the discharged waste gas.

[0028] Furthermore, the output end of the first flue gas discharge pipeline is connected to an external decarbonization and desulfurization system, and the output end of the second flue gas discharge pipeline is respectively connected to the first flue gas discharge pipeline and the external atmosphere.

[0029] Among them, a concentration detector is arranged on the second flue gas discharge pipeline to detect the concentration content of the flue gas discharged from the second flue gas discharge pipeline, and selectively output the flue gas to the first flue gas discharge pipeline or the external atmosphere according to the detection result.

[0030] On the other hand, a ship waste gas treatment process is also proposed. The ship waste gas includes engine flue gas and cabin waste gas including discharged waste gas and ventilation waste gas, and specifically includes the following steps:

[0031] Ozone is generated by an ozone generator;

[0032] The engine flue gas formed in the ship engine is mixed with the ozone in a flue gas-ozone mixer in a predetermined ratio to form a flue gas-ozone mixed gas. The ozone in the flue gas-ozone mixed gas is catalytically decomposed by a first catalytic oxidation reactor to form active oxygen atoms. With the aid of the active oxygen atoms and the catalytic action of the first catalytic oxidation reactor, methane or ammonia in the flue gas-ozone mixed gas is oxidized and decomposed and discharged into a first flue gas discharge pipeline;

[0033] Ventilation exhaust gas is mixed with the ozone in an exhaust gas-ozone mixer in a predetermined ratio to form an exhaust gas-ozone mixed gas. Part of the methane or ammonia in the exhaust gas-ozone mixed gas is incinerated by a burner, and at the same time, a second catalytic oxidation reactor catalytically decomposes the ozone to form active oxygen atoms. With the aid of the active oxygen atoms and the second catalytic oxidation reactor, the unincinerated part of methane or ammonia is oxidized and decomposed and discharged into a second flue gas discharge pipeline;

[0034] The discharge exhaust gas is input into the burner to provide a fuel source for the burner.

[0035] Further, the second flue gas discharge pipeline is communicated with the input end of the flue gas-ozone mixer;

[0036] The ship exhaust gas treatment process further includes the following steps:

[0037] When the reaction temperature of the flue gas-ozone mixer is lower than a preset temperature and the concentration of methane or ammonia in the engine flue gas increases, the output power of the burner is increased, and the gas discharged from the second flue gas discharge pipeline is controlled to flow back to the input end of the flue gas-ozone mixer to increase the mixing reaction temperature of the engine flue gas and the ozone in the flue gas-ozone mixer.

[0038] Further, it further includes the following steps:

[0039] The desorbed exhaust gas generated by the ship PSA nitrogen generator is input into the ozone generator to generate ozone.

[0040] Further, a bypass pipeline is connected between the flue gas-ozone mixer and the first flue gas discharge pipeline;

[0041] The ship exhaust gas treatment process further includes the following steps:

[0042] Detect the concentration of methane or ammonia in the flue gas-ozone mixed gas output by the flue gas-ozone mixer and generate a detection result;

[0043] When the detection result is greater than the set threshold value, control the flue gas-ozone mixed gas to pass through the first catalytic oxidation reactor, and after the oxidation decomposition is completed, discharge it through the first flue gas discharge pipeline;

[0044] When the detection result is less than the set threshold value, control the flue gas-ozone mixed gas to pass through the bypass pipeline, and complete the oxidation decomposition of methane or ammonia through the ozone in the flue gas-ozone mixed gas, and after the oxidation decomposition is completed, discharge it through the first flue gas discharge pipeline.

[0045] Compared with the prior art, the present invention has at least the following beneficial effects:

[0046] By setting up an engine flue gas treatment subsystem including an ozone generator to generate ozone gas, since ozone gas can effectively react with engine flue gas at a relatively low temperature (such as the temperature of the flue gas discharged from the engine), the purpose of efficiently treating waste gas can be achieved without significantly increasing the flue gas temperature additionally. Although the preliminary reaction of ozone and engine flue gas at a relatively low temperature can remove some pollutants, in order to further improve the treatment effect, a flue gas-ozone mixer and a first catalytic oxidation reactor are also provided, so that the flue gas-ozone mixed gas can enter the first catalytic oxidation reactor for a secondary catalytic oxidation reaction after the preliminary reaction, and the treatment effect of engine flue gas is further improved through a dual reaction mechanism.

[0047] In addition, a cabin exhaust gas treatment subsystem including a burner and a second catalytic oxidation reactor is also set up, and the output end of the ozone generator is connected to the ventilation exhaust gas pipeline. After ozone is mixed with the ventilation exhaust gas, the burner can burn part of the ventilation exhaust gas, and then under the catalytic oxidation of ozone and the second catalytic oxidation reactor, the remaining ventilation exhaust gas can be subjected to a secondary reaction treatment, further improving the treatment effect of the ventilation exhaust gas. Through the treatment method combining ozone and the second catalytic oxidation reactor, it is not necessary to maintain a high-temperature combustion environment like an RTO device, so there is no need to be equipped with a large regenerative structure and a complex gas supply system, so the volume occupied by the overall system can be effectively reduced, achieving the purpose of small occupied space and convenient installation and application.

[0048] In addition, by connecting the discharge exhaust gas to the burner, the discharge exhaust gas can be used as the fuel source for the burner to burn, so as to realize the full utilization of energy.

[0049] Therefore, by setting up the engine flue gas treatment subsystem and the cabin exhaust gas treatment subsystem, this system can comprehensively treat engine flue gas, discharge exhaust gas, and ventilation exhaust gas, so as to achieve the purpose of efficient utilization of resources. Compared with the method of separately configuring treatment equipment for different exhaust gases in the prior art, it can effectively reduce the space occupied by the equipment on the ship and also achieve the purpose of improving the space utilization rate of the ship.

[0050] Furthermore, by connecting the second flue gas discharge pipeline to the engine flue gas discharge pipeline through the first valve pipeline, when the temperature in the flue gas-ozone mixer connected to the engine flue gas discharge pipeline is lower than the optimal temperature for the mixed oxidation reaction of ozone and engine flue gas, the gas heated by the burner can be circulated to the engine flue gas discharge pipeline through the second flue gas discharge pipeline, thereby completing the temperature increase operation of the flue gas-ozone mixer and improving the mixed oxidation reaction effect of ozone and engine flue gas. That is, it can realize the recycling of heat by using the waste heat of the gas after the combustion oxidation of ventilation exhaust gas, without starting an additional heating device. In this way, while improving the mixed oxidation reaction effect of ozone and engine flue gas, it effectively reduces energy consumption, and further reduces the fuel cost and power cost during the operation of the ship, improving economic benefits.

[0051] Furthermore, by setting up an analysis exhaust gas pipeline, one end of the analysis exhaust gas pipeline is connected to the ship's PSA nitrogen generator, and the other end is connected to the ozone generator. Since the ship's PSA nitrogen generator will generate analysis exhaust gas during the process of producing nitrogen, this kind of exhaust gas usually contains a high concentration of oxygen. In the past, most of these analysis exhaust gases were directly discharged into the atmosphere, causing waste of resources. By introducing it into the ozone generator through the analysis exhaust gas pipeline, it can be used as a raw material for synthesizing ozone, realizing the resource recycling of exhaust gas. This not only reduces the dependence on external gas sources, reduces the cost of obtaining ozone raw materials, but also avoids the impact of exhaust gas emissions on the environment. Brief Description of the Drawings

[0052] Figure 1 It is a structural block diagram of the ship exhaust gas comprehensive treatment system in Embodiment 1 of the present invention.

[0053] Reference numerals in the drawings: 1. Ozone generator; 2. Flue gas-ozone mixer; 3. First catalytic oxidation reactor; 4. First flue gas discharge pipeline; 5. Engine flue gas discharge pipeline; 6. Burner; 7. Second catalytic oxidation reactor; 8. Second flue gas discharge pipeline; 9. Air intake pipeline; 10. Discharge exhaust gas discharge pipeline; 11. Ventilation exhaust gas discharge pipeline; 12. Exhaust gas-ozone mixer; 13. Analysis exhaust gas pipeline; 14. Gas concentration detection sensor; 15. Bypass pipeline; 16. Catalyst activation steam pipeline; 17. Heat exchange tube; 18. Pressure stabilizing valve; 19. Concentration detector. Detailed Embodiments

[0054] The integrated ship exhaust gas treatment system and ship exhaust gas treatment process of the present invention will be described in more detail below with reference to the schematic diagrams, in which the preferred embodiments of the present invention are shown. It should be understood that those skilled in the art can modify the present invention described herein while still achieving the beneficial effects of the present invention. Therefore, the following description should be understood as broad knowledge for those skilled in the art and not as a limitation on the present invention.

[0055] In the following paragraphs, the present invention will be described more specifically by way of example with reference to the accompanying drawings. According to the following description, the advantages and features of the present invention will be clearer. It should be noted that the drawings are all in a very simplified form and use non-precise scales, only for the purpose of conveniently and clearly assisting in explaining the purpose of the embodiments of the present invention.

[0056] Example 1

[0057] As Figure 1 shown, an integrated ship exhaust gas treatment system according to an embodiment of the present invention includes an engine flue gas treatment subsystem and a cabin exhaust gas treatment subsystem, so as to construct a complete and comprehensive ship exhaust gas treatment system, realize the classified and centralized treatment of various exhaust gases (such as engine flue gas, discharge exhaust gas, and ventilation exhaust gas), improve the treatment efficiency, reduce pollutant emissions, and enhance the pertinence and effectiveness of ship exhaust gas treatment.

[0058] The engine flue gas treatment subsystem includes an ozone generator 1, a flue gas-ozone mixer 2, a first catalytic oxidation reactor 3, and a first flue gas discharge pipeline 4 connected in sequence, and the input end of the flue gas-ozone mixer 2 is connected to an engine flue gas discharge pipeline 5, so as to build a coherent engine flue gas treatment process, ensure the orderliness and high efficiency of the treatment process, enable the engine flue gas to pass through each key treatment link in sequence, and ensure full purification.

[0059] Among them, the ozone generator 1 is used to generate highly oxidizing ozone, providing a key substance for subsequent oxidation reactions. In one example, the ozone generator 1 is a tubular arc ozone generator.

[0060] The flue gas-ozone mixer 2 is provided to enable the full mixing of ozone and engine flue gas, so that the oxidation reaction can proceed evenly.

[0061] The first catalytic oxidation reactor 3 plays a role in accelerating the decomposition of ozone to generate active oxygen atoms and jointly oxidizing and decomposing pollutants such as methane or ammonia in the engine flue gas with the active oxygen atoms.

[0062] That is, in the engine flue gas treatment subsystem, ozone gas is first generated by the ozone generator 1 and mixed with the engine flue gas for a preliminary reaction in the flue gas-ozone mixer 2. Then, the flue gas-ozone mixed gas enters the first catalytic oxidation reactor 3 for a secondary catalytic oxidation reaction, and finally is discharged through the first flue gas discharge pipeline 4, realizing the function of multi-stage oxidation and decomposition of methane or ammonia in the engine flue gas, thereby achieving the purpose of reducing pollution emissions.

[0063] It should be particularly noted that since ozone gas can decompose to generate active oxygen atoms at relatively low temperatures (such as 200°C - 300°C), these active oxygen atoms have extremely high oxidizing properties and can react rapidly with methane and ammonia to oxidize and decompose them. Therefore, in this application, the ozone gas generated by the ozone generator 1 is used as the main oxidant for engine flue gas and ventilation waste gas treatment, enabling efficient waste gas treatment without the need to significantly increase the flue gas temperature additionally, thus effectively avoiding the defects of energy consumption and cost increase caused by using additional heating equipment to increase the temperature in the prior art.

[0064] The cabin waste gas treatment subsystem includes a burner 6, a second catalytic oxidation reactor 7, and a second flue gas discharge pipeline 8 connected in sequence.

[0065] The input end of the second catalytic oxidation reactor 7 is connected to a ventilation waste gas discharge pipeline 11, and the ventilation waste gas discharge pipeline 11 is connected to the output end of the ozone generator 1 through a branch pipeline for transporting ozone. Moreover, an exhaust gas-ozone mixer 12 is provided on the ventilation waste gas discharge pipeline 11 for the full mixing of ventilation waste gas and ozone.

[0066] Among them, by setting the exhaust gas-ozone mixer 12, the ventilation waste gas and the ozone generated by the ozone generator 1 can be fully mixed in a predetermined ratio, thus creating good conditions for subsequent treatment in the burner 6 and the second catalytic oxidation reactor 7.

[0067] In addition, by connecting the input end of the burner 6 to an air inlet pipeline 9 and a discharge waste gas discharge pipeline 10 respectively, the discharge waste gas transported by the discharge waste gas discharge pipeline 10 can be used as the fuel of the burner 6 to avoid waste of resources. Moreover, with sufficient oxygen provided by the air inlet pipeline 9 for combustion support, the burner 6 can effectively perform preliminary incineration treatment on part of the methane or ammonia in the exhaust gas-ozone mixed gas entering it. This not only realizes the resource utilization of the discharge waste gas, reduces environmental pollution caused by waste gas emissions, but also reduces the ship's dependence on external fuel and effectively saves operating costs.

[0068] It should be noted that due to the input of ozone, when the waste gas-ozone mixed gas enters the second catalytic oxidation reactor 7, it can perform secondary catalytic oxidation on the waste gas preliminarily treated by the burner 6. Under the action of the catalyst, ozone decomposes to generate active oxygen atoms, and these active oxygen atoms cooperate with the catalyst to deeply oxidize and decompose the unburned part of methane or ammonia, converting it into harmless substances, and finally the treated gas is discharged through the second flue gas discharge pipeline 8.

[0069] It should be especially noted that the input end of the burner 6 is also connected to engine fuel gas (not shown in the figure). Since the source of the discharged waste gas depends on the pressure change of the storage tank and is therefore unstable, the burner 6 is connected to the engine fuel gas to enable the burner 6 to operate stably.

[0070] With the above arrangement, the system uses ozone as the main oxidant for engine exhaust gas and ventilation exhaust gas, enabling the decomposition treatment of engine exhaust gas without the need for external heating equipment. Specifically, when treating engine exhaust gas, the property that ozone decomposes to generate active oxygen atoms at a relatively low temperature (200°C - 300°C) is utilized. These active oxygen atoms rapidly react with pollutants such as methane and ammonia in the engine exhaust gas to achieve multi-stage oxidation decomposition, ensuring the treatment effect while avoiding the energy consumption and cost increase caused by using additional heating equipment.

[0071] When treating ventilation exhaust gas, there is no need to use an RTO device to maintain a high-temperature combustion environment for a long time. That is, only by fully mixing the ventilation exhaust gas with ozone in the waste gas-ozone mixer 12, first using the burner 6 to preliminarily incinerate some pollutants with the discharged waste gas as fuel, and then relying on the synergistic effect of the active oxygen atoms generated by the decomposition of ozone and the catalyst in the second catalytic oxidation reactor 7 for secondary catalytic oxidation. This not only effectively treats the ventilation exhaust gas and the discharged waste gas, but also reduces the fuel cost. At the same time, the system structure is compact, reducing the space occupation.

[0072] In summary, through the coordinated operation of the engine flue gas treatment subsystem and the cabin waste gas treatment subsystem, the efficient and low-cost treatment of various ship exhaust gases is achieved, successfully solving the problems of high energy consumption, complex equipment, large space occupation, and insufficient exhaust gas treatment in the prior art.

[0073] In other embodiments, a first valve pipeline is also provided to realize the recycling of heat energy.

[0074] Specifically, the second flue gas discharge pipeline 8 is connected to the engine flue gas discharge pipeline 5 through a first valve pipeline, which is used to increase the mixing reaction temperature of the engine flue gas and ozone in the flue gas-ozone mixer 2. That is, when the temperature in the flue gas-ozone mixer 2 connected to the engine flue gas discharge pipeline 5 is lower than the optimal temperature for the mixing and oxidation reaction of ozone and engine flue gas, the gas heated by the burner 6 can be circulated to the engine flue gas discharge pipeline 5 through the second flue gas discharge pipeline 8, so as to complete the temperature increase operation of the flue gas-ozone mixer 2 and improve the mixing and oxidation reaction effect of ozone and engine flue gas.

[0075] Among them, by utilizing the waste heat of the second flue gas discharge pipeline 8 to increase the reaction temperature, it is possible to effectively improve the mixing and oxidation reaction effect of ozone and engine flue gas without additional heating equipment. Furthermore, not only can the energy consumption and operating costs be effectively reduced, but also the efficient utilization of energy can be achieved.

[0076] In other embodiments, an analysis waste gas pipeline 13 is additionally provided, which can not only provide a raw material source for the ozone generator 1, but also realize the reuse of waste gas resources.

[0077] Specifically, the engine flue gas treatment subsystem further includes an analysis waste gas pipeline 13. One end of the analysis waste gas pipeline 13 is connected to the ship PSA nitrogen generator, and the other end is connected to the ozone generator 1, which is used to provide a gas raw material source for the ozone generated by the ozone generator 1.

[0078] It should be noted that the ship PSA nitrogen generator is a nitrogen production device based on the principle of pressure swing adsorption, usually composed of air compression, purification, adsorption, and control systems. It can separate and produce nitrogen with a purity of 95%-99.999% from the air to meet the nitrogen demand of the ship in scenarios such as cargo hold inerting when transporting flammable, explosive, and easily oxidizable goods, as well as fuel system protection, equipment purging and replacement, and fire extinguishing.

[0079] In the prior art, analysis waste gas is generated during the nitrogen production process of the ship PSA nitrogen generator. This kind of waste gas usually contains a high concentration of oxygen, but most of these analysis waste gases are directly discharged into the atmosphere. However, in this application, by setting the analysis waste gas pipeline 13 to introduce the analysis waste gas into the ozone generator 1, it can be used as a raw material for synthesizing ozone, thus realizing the function of waste gas resource recycling. Through the above settings, not only can the dependence on external gas sources be effectively reduced, the cost of obtaining ozone raw materials be reduced, but also the environmental impact of waste gas emissions can be avoided.

[0080] Furthermore, a gas concentration detection sensor 14 is provided at the input end of the first catalytic oxidation reactor 3, which is used to detect the concentration of ammonia or methane.

[0081] A bypass pipeline 15 is connected between the flue gas-ozone mixer 2 and the first flue gas discharge pipeline 4, and is used to selectively bypass or pass the gas output by the flue gas-ozone mixer 2 through the first catalytic oxidation reactor 3 according to the concentration detected by the gas concentration detection sensor 14.

[0082] Specifically, by setting the bypass pipeline 15, when the gas concentration detection sensor 14 detects that the ammonia or methane concentration at the input end of the first catalytic oxidation reactor 3 is low, it indicates that ozone can directly oxidize and decompose low-concentration ammonia or methane. Therefore, the gas output by the flue gas-ozone mixer 2 can directly enter the first flue gas discharge pipeline 4 through the bypass pipeline 15, so as to avoid unnecessary treatment processes of the gas in the first catalytic oxidation reactor 3, thereby improving the treatment efficiency and reducing energy consumption. When the ammonia or methane concentration is detected to be high, the gas passes through the first catalytic oxidation reactor 3, and the catalyst and the active oxygen atoms generated by the decomposition of ozone in the first catalytic oxidation reactor 3 are used to fully oxidize and decompose the pollutants, so as to ensure the treatment effect of ammonia or methane in the engine flue gas.

[0083] In other embodiments, the first catalytic oxidation reactor 3 and the second catalytic oxidation reactor 7 are further defined to improve the catalytic oxidation effect on ventilation exhaust gas and engine flue gas.

[0084] Specifically, the first catalytic oxidation reactor 3 and the second catalytic oxidation reactor 7 are both filled with catalyst fillers inside. Among them, the catalyst filler is one or more of copper oxide, manganese oxide and titanium dioxide. Due to the special crystal structure and electronic characteristics of catalysts such as copper oxide, manganese oxide and titanium dioxide, the activation energy of the reaction can be reduced. During the waste gas treatment process, when the waste gas is mixed with ozone and enters the catalytic oxidation reactor, these catalyst fillers can promote the more rapid decomposition of ozone to generate active oxygen atoms, so as to quickly react with pollutants such as methane and ammonia in the waste gas, greatly improving the oxidation decomposition speed, enabling the waste gas to be effectively treated in a short time, and improving the working efficiency of the entire waste gas treatment system.

[0085] In a further embodiment, in order to extend the service life of the system and prevent the formation of carbon deposition in the engine flue gas discharge pipeline 5 from affecting the subsequent catalytic oxidation decomposition effect, a catalyst activation steam pipeline 16 is additionally provided.

[0086] Among them, the output end of the catalyst activation steam pipeline 16 is connected to the engine flue gas discharge pipeline 5 and the ventilation exhaust gas discharge pipeline 11 through a second valve pipeline, and is respectively used to clean the carbon deposition formed by the flue gas in the engine flue gas discharge pipeline 5 and to purge the burner 6 connected to the ventilation exhaust gas discharge pipeline 11.

[0087] Specifically, when the ship is in operation and carbon deposits generated by the combustion of diesel fuel accumulate in equipment (such as the engine flue gas discharge pipeline 5), the catalyst activation steam pipeline 16 can be opened to allow high-temperature steam to enter the engine flue gas discharge pipeline 5. Then, in a strongly oxidizing and relatively high-temperature scenario, the steam can chemically react with the carbon deposits to generate water and carbon dioxide, so as to achieve the function of removing carbon deposits in the engine flue gas discharge pipeline 5, thereby avoiding the problem that the normal transportation of engine flue gas is disturbed due to the accumulation of carbon deposits.

[0088] Correspondingly, when impurities and unburned substances in the ventilation exhaust gas accumulate inside the burner 6 connected to the ventilation exhaust gas discharge pipeline 11, resulting in a reduction in combustion efficiency, the catalyst activation steam pipeline 16 can also be opened to allow steam to enter the burner 6 for purging, timely removing the accumulated substances, maintaining the good working performance of the burner 6, and ensuring the preliminary incineration effect of the ventilation exhaust gas.

[0089] In addition, a heat exchange pipe 17 for recovering the heat of the flue gas after incineration is provided inside the second catalytic oxidation reactor 7 for heat energy recovery and utilization. In one example, the heat exchange pipe 17 can be used to heat the water liquid to generate steam for supplying the steam in the catalyst activation steam pipeline 16, thereby effectively improving the energy utilization rate.

[0090] Furthermore, a pressure stabilizing valve 18 is provided on the discharge exhaust gas discharge pipeline 10. When the ship is in operation, since the supply pressure of the discharge exhaust gas is prone to fluctuate due to factors such as loading and unloading operations and the storage state of the goods, the pressure stabilizing valve 18 is set to sense the pressure change in real time. When the pressure is too high, the valve opening is automatically increased to release pressure, and when the pressure is too low, the opening is reduced to maintain pressure, so as to ensure the stable pressure of the discharge exhaust gas entering the burner 6, maintain a stable combustion flame, avoid problems such as flameout and deflagration caused by large pressure fluctuations, and ensure the safety and stability of the combustion process, providing a stable heat source for the preliminary incineration of the ventilation exhaust gas.

[0091] In other embodiments, the output end of the first flue gas discharge pipeline 4 is connected to an external decarbonization and desulfurization system, and the output end of the second flue gas discharge pipeline 8 is respectively connected to the first flue gas discharge pipeline 4 and the external atmosphere.

[0092] Among them, a concentration detector 19 is provided on the second flue gas discharge pipeline 8 for detecting the concentration of the flue gas discharged from the second flue gas discharge pipeline 8, and selectively outputting the flue gas to the first flue gas discharge pipeline 4 or the external atmosphere according to the detection result.

[0093] Specifically, by setting the concentration detector 19, when the flue gas concentration discharged from the second flue gas discharge pipeline 8 is relatively high, the flue gas can be automatically output to the first flue gas discharge pipeline 4 and enter the external decarbonization and desulfurization system together with the engine flue gas for in-depth treatment to ensure the waste gas treatment effect. When the flue gas concentration discharged from the second flue gas discharge pipeline 8 is relatively low and meets the emission standards, the flue gas can be directly output to the external atmosphere, reducing the load on the decarbonization and desulfurization system and lowering energy consumption and costs.

[0094] In summary, compared with the prior art, the ship waste gas comprehensive treatment system proposed in this embodiment has at least the following technical effects:

[0095] Through the close cooperation of the engine flue gas treatment subsystem and the cabin waste gas treatment subsystem, classified and centralized treatment of various ship waste gases is achieved. Specifically, the ozone generator 1 in the engine flue gas treatment subsystem generates ozone, which is transported through the branch pipeline to the ventilation waste gas discharge pipeline 11 of the cabin waste gas treatment subsystem and fully mixed with the ventilation waste gas in the waste gas-ozone mixer 12. This not only provides a key oxidant for the cabin waste gas treatment but also enables the ventilation waste gas to be more effectively treated in the subsequent burner 6 and the second catalytic oxidation reactor 7. In the cabin waste gas treatment subsystem, the gas heated by the burner 6 can be circulated to the engine flue gas discharge pipeline 5 through the first valve pipeline, raising the mixing and reaction temperature of the engine flue gas and ozone in the flue gas-ozone mixer 2 and promoting the oxidation reaction of ozone and engine flue gas in the engine flue gas treatment subsystem, thereby comprehensively improving the ship waste gas treatment efficiency and reducing pollutant emissions.

[0096] Moreover, by using ozone as the main oxidant and taking advantage of the property that ozone decomposes to generate active oxygen atoms at a relatively low temperature (200°C - 300°C), there is no need to rely on additional heating equipment to significantly increase the flue gas temperature, reducing energy consumption and cost increase.

[0097] In addition, by setting the analysis waste gas pipeline 13 to introduce the analysis waste gas generated by the ship PSA nitrogen generator into the ozone generator 1 as the raw material for synthesizing ozone, waste gas resource recycling is realized, reducing the dependence on external gas sources, lowering the cost of obtaining ozone raw materials, and at the same time avoiding the environmental impact of waste gas emissions. Finally, by using the discharge waste gas as the fuel for the burner 6, the resource utilization of the discharge waste gas is realized, reducing waste gas emissions, lowering the ship's dependence on external fuel, and saving operating costs.

[0098] Embodiment 2

[0099] This embodiment two proposes a ship waste gas treatment process. Compared with the prior art method of separately configuring treatment equipment for different waste gases, this process realizes the functions of comprehensive coverage, comprehensive treatment, and efficient energy utilization of ship waste gases.

[0100] Among them, the ship exhaust gas includes engine flue gas and hull exhaust gas including discharged exhaust gas and ventilation exhaust gas.

[0101] The ship exhaust gas treatment process specifically includes the following steps:

[0102] Ozone is generated by the ozone generator 1. By using ozone as the main oxidant and taking advantage of the characteristic that ozone decomposes to produce active oxygen atoms at a relatively low temperature (200°C - 300°C), heating equipment that significantly raises the flue gas temperature is not required, reducing energy consumption and cost increase.

[0103] The engine flue gas formed in the ship engine is evenly mixed with the ozone in the flue gas - ozone mixer 2 in a predetermined ratio to form a flue gas - ozone mixture gas. The ozone in the flue gas - ozone mixture gas is catalytically decomposed by the first catalytic oxidation reactor 3 to form active oxygen atoms. With the help of the active oxygen atoms and the catalytic action of the first catalytic oxidation reactor 3, methane or ammonia in the flue gas - ozone mixture gas is oxidized and decomposed and discharged into the first flue gas discharge pipeline 4, that is, the treatment effect on the engine flue gas is improved through a dual reaction mechanism.

[0104] The ventilation exhaust gas is evenly mixed with the ozone in the exhaust gas - ozone mixer 12 in a predetermined ratio to form an exhaust gas - ozone mixture gas. Part of the methane or ammonia in the exhaust gas - ozone mixture gas is incinerated by the burner 6, and at the same time, the second catalytic oxidation reactor 7 catalytically decomposes the ozone to form active oxygen atoms. With the help of the active oxygen atoms and the second catalytic oxidation reactor 7, the unincinerated part of methane or ammonia is oxidized and decomposed and discharged into the second flue gas discharge pipeline 8. Through the treatment method combining ozone and the second catalytic oxidation reactor 7, it is not necessary to maintain a high - temperature combustion environment like an RTO device. Therefore, there is no need to be equipped with a large regenerative structure and a complex gas supply system, so the volume occupied by the overall system can be effectively reduced, achieving the purpose of small occupied space and convenient installation and application.

[0105] The discharged exhaust gas is input into the burner 6 to provide a fuel source for the burner 6, realizing the full utilization of the discharged exhaust gas and avoiding waste of resources.

[0106] In this embodiment, the second flue gas discharge pipeline 8 is connected to the input end of the flue gas - ozone mixer 2, so that the heat of the gas formed after the burner 6 burns the exhaust gas - ozone mixture can be recycled, improving energy utilization efficiency.

[0107] Specifically, the ship exhaust gas treatment process further includes the following steps:

[0108] When the reaction temperature of the flue gas-ozone mixer 2 is lower than the preset temperature, and the concentration of methane or ammonia in the engine flue gas increases (which means that a stronger oxidation reaction is required to decompose these pollutants. By increasing the reaction temperature of the flue gas-ozone mixer 2, the rate of ozone decomposition to generate active oxygen atoms can be accelerated, and at the same time, the reaction activity of active oxygen atoms with pollutants such as methane and ammonia can be enhanced), increase the output power of the burner 6, and control the gas discharged from the second flue gas discharge pipeline 8 to flow back to the input end of the flue gas-ozone mixer 2, so as to increase the mixing reaction temperature of the engine flue gas and the ozone in the flue gas-ozone mixer 2, to ensure the waste gas treatment effect while improving the energy utilization rate.

[0109] In other embodiments, the ship exhaust gas treatment process further includes the following steps:

[0110] Input the desorbed exhaust gas generated by the ship PSA nitrogen generator into the ozone generator 1 to generate ozone, so as to realize the function of resource recycling of exhaust gas.

[0111] In a further embodiment, a bypass pipeline 15 is connected between the flue gas-ozone mixer 2 and the first flue gas discharge pipeline 4 to improve the treatment rate and reduce energy consumption.

[0112] Specifically, the ship exhaust gas treatment process further includes the following steps:

[0113] Detect the concentration of methane or ammonia in the flue gas-ozone mixed gas output by the flue gas-ozone mixer 2 and generate a detection result.

[0114] Among them, if the detection result is greater than the set threshold, then control the flue gas-ozone mixed gas to pass through the first catalytic oxidation reactor 3, and after the oxidation decomposition is completed, it is discharged through the first flue gas discharge pipeline 4.

[0115] If the detection result is less than the set threshold, then control the flue gas-ozone mixed gas to pass through the bypass pipeline 15, and complete the oxidation decomposition of methane or ammonia through the ozone in the flue gas-ozone mixed gas, and after the oxidation decomposition is completed, it is discharged through the first flue gas discharge pipeline 4.

[0116] That is, when the gas concentration detection sensor 14 detects that the ammonia or methane concentration at the input end of the first catalytic oxidation reactor 3 is low, it indicates that ozone can directly oxidize and decompose low-concentration ammonia or methane. Therefore, the gas output by the flue gas-ozone mixer 2 can be directly introduced into the first flue gas discharge pipeline 4 through the bypass pipeline 15, so as to avoid unnecessary treatment processes of the gas in the first catalytic oxidation reactor 3, thereby improving the treatment efficiency and reducing energy consumption. When the ammonia or methane concentration is detected to be high, the gas passes through the first catalytic oxidation reactor 3, and the catalyst in the first catalytic oxidation reactor 3 and the active oxygen atoms generated by the decomposition of ozone are used to fully oxidize and decompose pollutants to ensure the treatment effect of ammonia or methane in the engine flue gas.

[0117] In summary, compared with the method of separately configuring treatment equipment for different exhaust gases in the prior art, the ship exhaust gas treatment process described in this embodiment realizes the functions of comprehensive coverage, comprehensive treatment, and efficient energy utilization of ship exhaust gas.

[0118] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and its equivalent technologies, the present invention also intends to include these changes and modifications.

Claims

1. An integrated ship exhaust gas treatment system, characterized in that, It includes an engine flue gas treatment subsystem and a cabin exhaust gas treatment subsystem; The engine flue gas treatment subsystem includes an ozone generator, a flue gas-ozone mixer, a first catalytic oxidation reactor, and a first flue gas discharge pipeline connected in sequence; The input end of the flue gas-ozone mixer is connected to an engine flue gas discharge pipeline; The cabin exhaust gas treatment subsystem includes a burner, a second catalytic oxidation reactor, and a second flue gas discharge pipeline connected in sequence; The input end of the burner is respectively connected to an air inlet pipeline and a discharge exhaust gas discharge pipeline; The input end of the second catalytic oxidation reactor is connected to a ventilation exhaust gas discharge pipeline; Among them, the ventilation exhaust gas discharge pipeline is connected to the output end of the ozone generator through a branch pipeline, and an exhaust gas-ozone mixer is arranged on the ventilation exhaust gas discharge pipeline; The engine flue gas treatment subsystem further includes an analysis exhaust gas pipeline; One end of the analysis exhaust gas pipeline is connected to a ship PSA nitrogen generator, and the other end is connected to the ozone generator, which is used to provide a gas raw material source for the ozone generated by the ozone generator; The ship exhaust gas comprehensive treatment system further includes a catalyst activation steam pipeline; The output end of the catalyst activation steam pipeline is connected to the engine flue gas discharge pipeline and the ventilation exhaust gas discharge pipeline through a second valve pipeline, which is respectively used to clean the carbon deposits formed by the flue gas in the engine flue gas discharge pipeline and blow the burner connected to the ventilation exhaust gas discharge pipeline; 2. The integrated ship exhaust gas treatment system according to claim 1, wherein, The second flue gas discharge pipeline is connected to the engine flue gas discharge pipeline through a first valve pipeline, which is used to increase the mixing reaction temperature of the engine flue gas and ozone in the flue gas-ozone mixer; 3. The integrated ship exhaust gas treatment system according to claim 1, characterized in that, A gas concentration detection sensor is arranged at the input end of the first catalytic oxidation reactor, which is used to detect the concentration of ammonia or methane; A bypass pipeline is connected between the flue gas-ozone mixer and the first flue gas discharge pipeline, which is used to selectively bypass or pass the gas output by the flue gas-ozone mixer through the first catalytic oxidation reactor according to the concentration detected by the gas concentration detection sensor; 4. The integrated ship exhaust gas treatment system according to claim 1, characterized in that, Both the first catalytic oxidation reactor and the second catalytic oxidation reactor are internally filled with catalyst fillers; The catalyst filler is one or more of copper oxide, manganese oxide, and titanium dioxide; 5. The integrated ship exhaust gas treatment system according to claim 1, characterized in that, A heat exchange tube for recovering the waste heat of the incinerated flue gas is arranged inside the second catalytic oxidation reactor; 6. The integrated ship exhaust gas treatment system according to claim 1, characterized in that, The ozone generator is a tubular arc ozone generator; 7. The integrated ship exhaust gas treatment system according to claim 1, wherein, A pressure stabilizing valve is arranged on the discharge exhaust gas discharge pipeline; 8. The integrated ship exhaust gas treatment system according to claim 1, characterized in that, The output end of the first flue gas discharge pipeline is connected to an external decarbonization and desulfurization system, and the output end of the second flue gas discharge pipeline is respectively connected to the first flue gas discharge pipeline and the external atmosphere; Among them, a concentration detector is arranged on the second flue gas discharge pipeline, which is used to detect the concentration content of the flue gas discharged from the second flue gas discharge pipeline, and selectively output the flue gas to the first flue gas discharge pipeline or the external atmosphere according to the detection result; 9. A ship exhaust gas treatment process, characterized in that, The ship exhaust gas includes engine flue gas and cabin exhaust gas including discharge exhaust gas and ventilation exhaust gas, and specifically includes the following steps: Generate ozone through an ozone generator; Mix the engine flue gas formed in the ship engine with the ozone evenly in a flue gas-ozone mixer according to a predetermined ratio to form a flue gas-ozone mixed gas. Catalytically decompose the ozone in the flue gas-ozone mixed gas through a first catalytic oxidation reactor to form active oxygen atoms. Oxidatively decompose methane or ammonia in the flue gas-ozone mixed gas by means of the active oxygen atoms and the catalytic action of the first catalytic oxidation reactor, and discharge it to a first flue gas discharge pipeline; Mix the ventilation exhaust gas with the ozone evenly in an exhaust gas-ozone mixer according to a predetermined ratio to form an exhaust gas-ozone mixed gas. Incinerate part of the methane or ammonia in the exhaust gas-ozone mixed gas through a burner. At the same time, a second catalytic oxidation reactor catalytically decomposes the ozone to form active oxygen atoms. Oxidatively decompose the unincinerated part of methane or ammonia by means of the active oxygen atoms and the second catalytic oxidation reactor, and discharge it to a second flue gas discharge pipeline; Input the discharge exhaust gas into the burner to provide a fuel source for the burner.

10. The ship exhaust gas treatment process according to claim 9, characterized in that, The second flue gas discharge pipeline is communicated with the input end of the flue gas-ozone mixer; The ship exhaust gas treatment process further includes the following steps: When the reaction temperature of the flue gas-ozone mixer is lower than the preset temperature and the concentration of methane or ammonia in the engine flue gas increases, increase the output power of the burner and control the gas discharged from the second flue gas discharge pipeline to flow back to the input end of the flue gas-ozone mixer to increase the mixing reaction temperature of the engine flue gas and the ozone in the flue gas-ozone mixer.

11. The ship exhaust gas treatment process according to claim 10, characterized in that, It further includes the following steps: Input the desorbed exhaust gas generated by the ship PSA nitrogen generator into the ozone generator to generate ozone.

12. The ship exhaust gas treatment process according to claim 10, characterized in that, A bypass pipeline is connected between the flue gas-ozone mixer and the first flue gas discharge pipeline; The ship exhaust gas treatment process further includes the following steps: Detect the concentration of methane or ammonia in the flue gas-ozone mixed gas output by the flue gas-ozone mixer and generate a detection result; If the detection result is greater than the set threshold, control the flue gas-ozone mixed gas to pass through the first catalytic oxidation reactor, and after the oxidative decomposition is completed, discharge it through the first flue gas discharge pipeline; If the detection result is less than the set threshold, control the flue gas-ozone mixed gas to pass through the bypass pipeline, complete the oxidative decomposition of methane or ammonia through the ozone in the flue gas-ozone mixed gas, and after the oxidative decomposition is completed, discharge it through the first flue gas discharge pipeline.

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