Ship waste gas comprehensive treatment system and ship waste gas treatment process

Abstract

The invention discloses a ship waste gas comprehensive treatment system and a ship waste gas treatment process. The ship waste gas comprehensive treatment system comprises an engine flue gas treatment subsystem and a cabin waste gas treatment subsystem, the engine flue gas treatment subsystem comprises 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 with an engine flue gas emission pipeline; the cabin waste gas treatment subsystem comprises a combustor, a second catalytic oxidation reactor and a second flue gas discharge pipeline; the input end of the combustor is connected with an air inlet pipeline and a discharged waste gas discharging pipeline. The input end of the second catalytic oxidation reactor is connected with a ventilation waste gas discharge pipeline; the ventilation waste gas discharge pipeline is connected with the output end of the ozone generator, and a waste gas-ozone mixer is arranged on the ventilation waste gas discharge pipeline. Through the arrangement, comprehensive coverage and comprehensive treatment of ship waste gas can be achieved, and efficient utilization of resources is achieved.

Description

Technical Field

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

[0002] As the global energy structure accelerates its transition to clean energy, the demand for marine transportation of LNG (liquefied natural gas) as an efficient and clean energy source has increased dramatically, and LNG ships have become a key link in energy transportation. However, while LNG ships contribute to energy transportation, the problem of waste gas emissions generated during their operation has gradually become prominent.

[0003] First, in response to the requirements of energy conservation and emission reduction, in order to reduce pollutant emissions caused by traditional fuel, most LNG ships currently use dual-fuel engines (i.e. diesel mixed with LNG as fuel, the main component is methane or ammonia). 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, and the greenhouse effect of methane is about 28-36 times that of carbon dioxide. A large amount of methane escaped and discharged into the atmosphere will greatly aggravate the trend of global warming.

[0004] At present, the conventional treatment method for methane and ammonia escaping from the engine flue gas of LNG ships is catalytic oxidation. However, since the catalytic oxidation reaction usually needs to be carried out effectively in the temperature range of 300℃-400℃, and the flue gas temperature discharged from the LNG ship engine is generally in the range of 200℃-300℃, in order to meet the needs of catalytic oxidation treatment, additional heating equipment such as burners or electric heaters are often required to increase the flue gas temperature. However, this method not only greatly increases the energy consumption and operating costs of the ship, but also makes the equipment system more complicated and occupies the already limited space on the ship. In addition, during the operation of the ship, the engine flue gas will inevitably contain oil, dust or other impurities due to combustion. These substances are very easy to adhere to the surface of the catalyst, causing the catalyst to be poisoned and inactivated, affecting the effect of catalytic oxidation, and then the exhaust gas treatment will not meet environmental protection standards.

[0005] Secondly, when treating the ventilation exhaust gas of LNG ships, a regenerative thermal oxidation (RTO) device is usually used. However, this method also has certain disadvantages. Specifically, due to the huge amount of ventilation exhaust gas emitted by LNG ships and the low concentration of combustible gas, it cannot be directly burned and treated. Additional fuel gas is required to maintain the oxidation decomposition temperature of the RTO device at about 700°C, which will increase fuel costs. In addition, due to the large size and complex structure of the RTO device, it requires a large installation space and complex supporting facilities, making it difficult to reasonably install and set up the RTO device in the limited space on board.

[0006] Finally, during the process of loading, unloading and storing LNG, LNG ships will produce waste gas due to changes in pressure in the storage tanks to avoid equipment damage. The main components of these waste gases are high-purity methane or ammonia. Currently, these waste gases are usually discharged directly into the atmosphere and cannot be fully utilized, resulting in a waste of resources.

[0007] Therefore, a comprehensive ship exhaust gas 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 comprehensive ship exhaust gas treatment system and a ship exhaust gas treatment process, so as to achieve comprehensive coverage and comprehensive treatment of ship exhaust gas and realize 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 in the ship, thereby achieving the purpose of improving the space utilization rate of the ship.

[0009] In order to solve the above technical problems, the present invention provides a comprehensive ship exhaust gas treatment system, including an engine smoke treatment subsystem and a cabin exhaust gas treatment subsystem; The engine smoke treatment subsystem includes an ozone generator, a smoke-ozone mixer, a first catalytic oxidation reactor and a first smoke exhaust pipeline connected in sequence; The input end of the flue gas-ozone mixer is connected to the engine flue gas exhaust pipeline; The cabin exhaust gas treatment subsystem includes a burner, a second catalytic oxidation reactor and a second flue gas exhaust pipeline connected in sequence; The input end of the burner is respectively connected to an air intake pipeline and a waste gas discharge pipeline; The input end of the second catalytic oxidation reactor is connected to a ventilation exhaust gas discharge pipeline; Wherein, 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.

[0010] Furthermore, the second smoke exhaust pipeline is connected to the engine smoke exhaust pipeline via a first valve pipeline, so as to increase the mixing reaction temperature of the engine smoke and ozone in the smoke-ozone mixer.

[0011] Furthermore, the engine smoke treatment subsystem also includes an exhaust gas analysis pipeline; One end of the analytical waste gas pipeline is connected to the ship PSA nitrogen generator, and the other end is connected to the ozone generator, so as to provide a gas raw material source for the ozone generated by the ozone generator.

[0012] Furthermore, a gas concentration detection sensor is provided at the input end of the first catalytic oxidation reactor for detecting the concentration of ammonia or methane; A bypass pipeline is connected between the flue gas-ozone mixer and the first flue gas exhaust 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.

[0013] Furthermore, the first catalytic oxidation reactor and the second catalytic oxidation reactor are both filled with catalyst fillers; The catalyst filler is one or more of copper oxide, manganese oxide and titanium dioxide.

[0014] Further, it also includes a catalyst activation steam pipeline; The output end of the catalyst activation steam pipeline is connected to the engine smoke exhaust pipeline and the ventilation exhaust gas exhaust pipeline through a second valve pipeline, which is used to clean the carbon deposits formed by the smoke in the engine smoke exhaust pipeline and to purge the burner connected to the ventilation exhaust gas exhaust pipeline.

[0015] Furthermore, a heat exchange tube for recovering the residual heat of the flue gas after incineration is provided inside the second catalytic oxidation reactor.

[0016] Furthermore, the ozone generator is a tubular arc ozone generator.

[0017] Furthermore, a pressure stabilizing valve is provided on the exhaust gas discharge pipeline.

[0018] Furthermore, the output end of the first flue gas exhaust pipeline is connected to an external decarbonization and desulfurization system, and the output end of the second flue gas exhaust pipeline is connected to the first flue gas exhaust pipeline and the external atmosphere respectively; The second smoke exhaust pipeline is provided with a concentration detector for detecting the concentration of the smoke exhausted from the second smoke exhaust pipeline, and selectively outputting the smoke to the first smoke exhaust pipeline or the external atmosphere according to the detection result.

[0019] On the other hand, a ship exhaust gas treatment process is also proposed, wherein the ship exhaust gas includes engine smoke and cabin exhaust gas including discharge exhaust gas and ventilation exhaust gas, and specifically includes the following steps: Ozone is generated by an ozone generator; The engine smoke generated in the ship engine and the ozone are uniformly mixed in a predetermined ratio in a smoke-ozone mixer to form a smoke-ozone mixed gas, the ozone in the smoke-ozone mixed gas is catalytically decomposed by a first catalytic oxidation reactor to form active oxygen atoms, and the methane or ammonia in the smoke-ozone mixed gas is oxidized and decomposed by the active oxygen atoms and the catalytic action of the first catalytic oxidation reactor, and discharged to a first smoke exhaust pipeline; The ventilation exhaust gas and the ozone are uniformly mixed in a predetermined ratio in an exhaust gas-ozone mixer to form an exhaust gas-ozone mixed gas, a part of the methane or ammonia in the exhaust gas-ozone mixed gas is incinerated by a burner, and at the same time, the second catalytic oxidation reactor catalytically decomposes the ozone to form active oxygen atoms, and the unincinerated part of the methane or ammonia is oxidized and decomposed by means of the active oxygen atoms and the second catalytic oxidation reactor, and discharged to the second flue gas exhaust pipeline; The exhaust gas is input into the burner to provide a fuel source for the burner.

[0020] Further, the second smoke exhaust pipeline is connected to the input end of the smoke-ozone mixer; The ship exhaust gas treatment process also 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, the output power of the burner is increased, and the gas discharged from the second flue gas exhaust pipeline is controlled to flow back to the input end of the flue gas-ozone mixer, so as to increase the mixing reaction temperature of the engine flue gas and the ozone in the flue gas-ozone mixer.

[0021] Furthermore, the method further comprises the following steps: The decomposed exhaust gas generated by the ship's PSA nitrogen generator is input into the ozone generator to generate ozone.

[0022] Furthermore, a bypass pipeline is connected between the flue gas-ozone mixer and the first flue gas exhaust pipeline; The ship exhaust gas treatment process also includes the following steps: Detecting the concentration of methane or ammonia in the flue gas-ozone mixed gas output by the flue gas-ozone mixer and generating a detection result; If the detection result is greater than the set threshold, the flue gas-ozone mixed gas is controlled to pass through the first catalytic oxidation reactor, and is discharged from the first flue gas exhaust pipeline after the oxidation and decomposition are completed; If the detection result is less than the set threshold, the flue gas-ozone mixed gas is controlled to pass through the bypass pipeline, and the ozone in the flue gas-ozone mixed gas is used to complete the oxidation decomposition of methane or ammonia, and after the oxidation decomposition is completed, it is discharged from the first flue gas exhaust pipeline.

[0023] Compared with the prior art, the present invention has at least the following beneficial effects: An engine flue gas treatment subsystem including an ozone generator is provided to generate ozone gas. Since ozone gas can effectively react with engine flue gas at a relatively low temperature (such as the temperature of exhaust flue gas from the engine), the purpose of efficiently treating exhaust gas can be achieved without significantly increasing the flue gas temperature. Although the initial 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 initial reaction, and the treatment effect of engine flue gas is further improved through a dual reaction mechanism.

[0024] In addition, by setting up a cabin exhaust gas treatment subsystem including a burner and a second catalytic oxidation reactor, and connecting the output end of the ozone generator to the ventilation exhaust gas pipeline, after the ozone and the ventilation exhaust gas are mixed, 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 secondary reaction treatment, further improving the ventilation exhaust gas treatment effect. Through the treatment method of combining ozone with the second catalytic oxidation reactor, it is not necessary to maintain a high-temperature combustion environment like the RTO device, so there is no need to equip a large heat storage structure and a complex gas supply system, so the volume occupied by the overall system can be effectively reduced, achieving the purpose of occupying a small space and being easy to install and apply.

[0025] In addition, by connecting the discharged waste gas to the burner, the discharged waste gas can be used as a fuel source for combustion of the burner to achieve full utilization of energy.

[0026] Therefore, this system sets up an engine smoke treatment subsystem and a cabin exhaust gas treatment subsystem to achieve comprehensive treatment of engine smoke, unloading exhaust gas and ventilation exhaust gas, thereby achieving 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 in the ship, and also achieve the purpose of improving the space utilization rate of the ship.

[0027] Furthermore, by connecting the second flue gas exhaust pipeline with the engine flue gas exhaust pipeline through the first valve pipeline, when the temperature in the flue gas-ozone mixer connected to the engine flue gas exhaust 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 exhaust pipeline through the second flue gas exhaust 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, the waste heat of the gas after the combustion and oxidation of the ventilation exhaust gas can be used to realize the recycling of heat without starting an additional heating device, thereby achieving the purpose of improving the mixed oxidation reaction effect of ozone and engine flue gas while effectively reducing energy consumption, thereby reducing the fuel cost and electricity cost during the operation of the ship, and improving economic benefits.

[0028] Furthermore, by setting up an analytical waste gas pipeline, and connecting one end of the analytical waste gas pipeline to the ship's PSA nitrogen generator and the other end to the ozone generator, since the ship's PSA nitrogen generator will produce analytical waste gas in the process of making nitrogen, this type of waste gas usually contains a high concentration of oxygen. In the past, most of these analytical waste gases were directly discharged into the atmosphere, resulting in a waste of resources. However, by introducing it into the ozone generator through the analytical waste gas pipeline, it can be used as a raw material for synthesizing ozone, realizing the resource recycling of waste gas. This not only reduces the dependence on external gas sources and reduces the cost of obtaining ozone raw materials, but also avoids the impact of waste gas emissions on the environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a structural block diagram of the ship exhaust comprehensive treatment system in Example 1 of the present invention.

[0030] Reference numerals: 1. Ozone generator; 2. Flue gas-ozone mixer; 3. First catalytic oxidation reactor; 4. First flue gas exhaust pipeline; 5. Engine flue gas exhaust pipeline; 6. Burner; 7. Second catalytic oxidation reactor; 8. Second flue gas exhaust pipeline; 9. Air intake pipeline; 10. Discharge exhaust gas exhaust pipeline; 11. Ventilation exhaust gas exhaust 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 regulating valve; 19. Concentration detector. DETAILED DESCRIPTION

[0031] The following will be described in more detail with reference to the schematic diagram of the ship exhaust gas comprehensive treatment system and the ship exhaust gas treatment process of the present invention, wherein the preferred embodiment of the present invention is shown, and it should be understood that those skilled in the art can modify the present invention described herein and still achieve the beneficial effects of the present invention. Therefore, the following description should be understood as being widely known to those skilled in the art and not as a limitation of the present invention.

[0032] The present invention is described in more detail in the following paragraphs by way of example with reference to the accompanying drawings. The advantages and features of the present invention will become more apparent from the following description. It should be noted that the accompanying drawings are in very simplified form and are not in exact proportions, and are only used to facilitate and clearly assist in illustrating the purpose of the embodiments of the present invention.

[0033] Example 1

[0034] like Figure 1 As shown, an embodiment of the present invention proposes a comprehensive ship exhaust gas treatment system, including an engine smoke 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 centralized treatment of various exhaust gases (such as engine smoke, unloading exhaust gas and ventilation exhaust gas), improve the treatment efficiency, reduce pollutant emissions, and enhance the pertinence and effectiveness of ship exhaust gas treatment.

[0035] 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 exhaust pipeline 4 which are connected in sequence, and the input end of the flue gas-ozone mixer 2 is connected to the engine flue gas exhaust pipeline 5 to build a coherent engine flue gas treatment process, ensure the orderliness and efficiency of the treatment process, and enable the engine flue gas to pass through each key treatment link in sequence to ensure sufficient purification.

[0036] The ozone generator 1 is used to generate highly oxidizing ozone to provide key substances for subsequent oxidation reactions. In one example, the ozone generator 1 is a tubular arc ozone generator.

[0037] The purpose of the flue gas-ozone mixer 2 is to fully mix the ozone with the engine flue gas so that the oxidation reaction can proceed evenly.

[0038] The first catalytic oxidation reactor 3 serves to accelerate the decomposition of ozone to produce active oxygen atoms and cooperate with the active oxygen atoms to further oxidize and decompose pollutants such as methane or ammonia in the engine smoke.

[0039] That is, in the engine flue gas treatment subsystem, ozone gas is first generated by the ozone generator 1 to be mixed with the engine flue gas in the flue gas-ozone mixer 2 for a preliminary reaction, and then the flue gas-ozone mixed gas enters the first catalytic oxidation reactor 3 for a second catalytic oxidation reaction, and is finally discharged from the first flue gas exhaust pipeline 4, thereby 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.

[0040] It should be noted that, since ozone gas can be decomposed to produce 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 quickly 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 the treatment of engine smoke and ventilation exhaust gas, which can effectively treat the exhaust gas without the need to significantly increase the temperature of the smoke, thereby effectively avoiding the defects of energy consumption and cost increase caused by the use of additional heating equipment to increase the temperature in the prior art.

[0041] The cabin exhaust gas treatment subsystem includes a burner 6, a second catalytic oxidation reactor 7 and a second flue gas exhaust pipeline 8 which are connected in sequence.

[0042] The input end of the second catalytic oxidation reactor 7 is connected to a ventilation exhaust gas discharge pipeline 11, and the ventilation exhaust gas discharge pipeline 11 is connected to the output end of the ozone generator 1 through a branch pipeline for transporting ozone. In addition, the ventilation exhaust gas discharge pipeline 11 is provided with an exhaust gas-ozone mixer 12 for fully mixing the ventilation exhaust gas and ozone.

[0043] Among them, by setting up the exhaust gas-ozone mixer 12, the ventilation exhaust gas and the ozone generated by the ozone generator 1 can be fully mixed in a predetermined ratio, thereby creating good conditions for subsequent treatment in the burner 6 and the second catalytic oxidation reactor 7.

[0044] In addition, the input end of the burner 6 is connected to the air intake pipeline 9 and the discharge exhaust gas discharge pipeline 10 respectively, so that the discharge exhaust gas transported by the discharge exhaust gas discharge pipeline 10 can be used as the fuel of the burner 6 to avoid the waste of resources, and the burner 6 can effectively perform preliminary incineration treatment on part of the methane or ammonia in the exhaust gas-ozone mixed gas entering therein under the sufficient oxygen combustion provided by the air intake pipeline 9. This not only realizes the resource utilization of the discharge exhaust gas, reduces the pollution of the environment by exhaust gas emissions, but also reduces the dependence of the ship on external fuel, effectively saving operating costs.

[0045] It should be noted that, due to the input of ozone, when the exhaust gas-ozone mixed gas enters the second catalytic oxidation reactor 7, the exhaust gas that has been preliminarily treated by the burner 6 can be subjected to secondary catalytic oxidation. Under the action of the catalyst, the ozone decomposes to produce active oxygen atoms, which work synergistically with the catalyst to deeply oxidize and decompose the unburned part of methane or ammonia to convert it into harmless substances, and the treated gas is finally discharged through the second flue gas exhaust pipeline 8.

[0046] It should also be noted that the input end of the burner 6 is also connected to the engine fuel gas (not shown in the figure). Since the source of the discharged exhaust gas depends on the pressure change of the storage tank and is therefore not stable, the burner 6 can be operated stably by connecting the burner 6 to the engine fuel gas.

[0047] Through the above arrangement, this system uses ozone as the main oxidant for engine exhaust and ventilation exhaust, so that the decomposition treatment of engine exhaust can be completed without the need for external heating equipment. Specifically, when treating engine exhaust, the characteristic of ozone decomposing at a relatively low temperature (200℃-300℃) to produce active oxygen atoms is utilized. These active oxygen atoms react rapidly with pollutants such as methane and ammonia in the engine exhaust to achieve multi-stage oxidation decomposition, which not only ensures the treatment effect, but also avoids the energy consumption and cost increase caused by the use of additional heating equipment.

[0048] When treating the 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, it is only necessary to fully mix the ventilation exhaust gas and ozone in the exhaust gas-ozone mixer 12, first use the burner 6 to use the discharged exhaust gas as fuel to preliminarily incinerate some pollutants, and then use the synergistic effect of the active oxygen atoms produced by the decomposition of ozone in the second catalytic oxidation reactor 7 and the catalyst to carry out secondary catalytic oxidation. This not only effectively treats the ventilation exhaust gas and the discharged exhaust gas, but also reduces the fuel cost. At the same time, the system structure is compact and the space occupancy is reduced.

[0049] In summary, through the coordinated operation of the engine smoke treatment subsystem and the cabin exhaust gas treatment subsystem, 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 existing technology.

[0050] In other embodiments, a first valve pipeline is further provided to achieve recycling of heat energy.

[0051] Specifically, the second flue gas exhaust pipeline 8 is connected to the engine flue gas exhaust pipeline 5 through a first valve pipeline, and is used to increase the mixed 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 exhaust pipeline 5 is lower than the optimal temperature of the mixed oxidation reaction of ozone and engine flue gas, the gas heated by the burner 6 can be circulated to the engine flue gas exhaust pipeline 5 through the second flue gas exhaust pipeline 8, thereby completing the temperature increase operation of the flue gas-ozone mixer 2 and improving the mixed oxidation reaction effect of ozone and engine flue gas.

[0052] Among them, by utilizing the waste heat of the second flue gas exhaust pipeline 8 to increase the reaction temperature, it is possible to effectively achieve the mixed oxidation reaction of ozone and engine flue gas without the need for additional heating equipment, thereby effectively reducing energy consumption and operating costs and achieving efficient use of energy.

[0053] In other embodiments, an exhaust gas analysis pipeline 13 is additionally provided to provide a source of raw materials for the ozone generator 1 and to realize the recycling of exhaust gas resources.

[0054] Specifically, the engine flue gas treatment subsystem further includes an exhaust gas analysis pipeline 13 , one end of which is connected to the ship PSA nitrogen generator, and the other end of which is connected to the ozone generator 1 , for providing a gas raw material source for the ozone generated by the ozone generator 1 .

[0055] It should be noted that the ship PSA nitrogen generator is a nitrogen generator based on the principle of pressure swing adsorption, usually composed of air compression, purification, adsorption and control system. It can separate and produce nitrogen with a purity of 95%-99.999% from the air, which is used to meet the nitrogen demand for cargo hold inerting when transporting flammable, explosive and oxidizable goods, as well as fuel system protection, equipment purging and replacement, and fire fighting.

[0056] In the prior art, the ship PSA nitrogen generator will produce decomposition waste gas in the process of producing nitrogen. This type of waste gas usually contains a high concentration of oxygen, but most of these decomposition waste gases are directly discharged into the atmosphere. The present application sets a decomposition waste gas pipeline 13 to introduce the decomposition waste gas into the ozone generator 1, which can be used as a raw material for synthesizing ozone, thereby realizing the function of waste gas resource recycling. Through the above-mentioned setting, it can not only effectively reduce the dependence on external gas sources and reduce the cost of obtaining ozone raw materials, but also avoid the impact of waste gas emissions on the environment.

[0057] Furthermore, a gas concentration detection sensor 14 is provided at the input end of the first catalytic oxidation reactor 3 for detecting the concentration of ammonia or methane.

[0058] A bypass pipeline 15 is connected between the flue gas-ozone mixer 2 and the first flue gas exhaust pipeline 4, which 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.

[0059] Specifically, by setting the bypass line 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 means that ozone can directly oxidize and decompose the low-concentration ammonia or methane, so the gas output from the flue gas-ozone mixer 2 can be directly passed through the bypass line 15 to enter the first flue gas exhaust line 4, thereby avoiding unnecessary treatment processes of the gas in the first catalytic oxidation reactor 3, thereby improving the treatment efficiency and reducing energy consumption. When a high concentration of ammonia or methane is detected, the gas passes through the first catalytic oxidation reactor 3, and the active oxygen atoms generated by the decomposition of the catalyst and 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.

[0060] In other embodiments, the first catalytic oxidation reactor 3 and the second catalytic oxidation reactor 7 are further defined to enhance the catalytic oxidation effect on the ventilation exhaust gas and the engine smoke.

[0061] Specifically, the first catalytic oxidation reactor 3 and the second catalytic oxidation reactor 7 are both filled with catalyst fillers. Among them, the catalyst fillers are one or more of copper oxide, manganese oxide and titanium dioxide. Since catalysts such as copper oxide, manganese oxide and titanium dioxide have special crystal structures and electronic properties, they can reduce the activation energy of the reaction, so that 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 ozone to decompose more quickly to produce active oxygen atoms, so that they can quickly react with pollutants such as methane and ammonia in the waste gas, greatly improving the speed of oxidation decomposition, so that the waste gas can be effectively treated in a shorter time, and the working efficiency of the entire waste gas treatment system is improved.

[0062] In a further embodiment, in order to extend the service life of the system and prevent the subsequent catalytic oxidation decomposition effect from being affected by the formation of carbon deposits in the engine smoke exhaust pipeline 5, a catalyst activation steam pipeline 16 is further provided.

[0063] Among them, the output end of the catalyst activation steam pipeline 16 is connected to the engine smoke exhaust pipeline 5 and the ventilation exhaust gas exhaust pipeline 11 through a second valve pipeline, which is used to clean the carbon deposits formed by the smoke in the engine smoke exhaust pipeline 5 and to purge the burner 6 connected to the ventilation exhaust gas exhaust pipeline 11.

[0064] Specifically, when the ship is in operation, when carbon deposits generated by the combustion of diesel fuel accumulate in the equipment (such as the engine smoke exhaust pipe 5), the catalyst activation steam pipe 16 can be opened to allow high-temperature steam to enter the engine smoke exhaust pipe 5. Then, under strong oxidation and high temperature conditions, the steam can chemically react with the carbon deposits to generate water and carbon dioxide, thereby achieving the function of eliminating carbon deposits in the engine smoke exhaust pipe 5, thereby avoiding the problem of carbon deposits interfering with the normal transportation of engine smoke.

[0065] Correspondingly, when the combustion efficiency of the burner 6 connected to the ventilation exhaust gas discharge pipeline 11 is reduced due to the accumulation of impurities and incompletely burned materials in the ventilation exhaust gas, the catalyst activation steam pipeline 16 can be opened to allow steam to enter the burner 6 for purging, thereby clearing the deposits in time, maintaining the good working performance of the burner 6, and ensuring the initial incineration effect of the ventilation exhaust gas.

[0066] In addition, a heat exchange tube 17 for recovering the waste heat of the flue gas after incineration is provided inside the second catalytic oxidation reactor 7 to recover the heat energy. In one example, the heat exchange tube 17 can be used to heat the water liquid to generate steam for supplying steam in the catalyst activation steam pipeline 16, thereby effectively improving the utilization rate of energy.

[0067] Furthermore, a pressure stabilizing valve 18 is provided on the exhaust gas discharge pipeline 10. When the ship is in operation, the supply pressure of the exhaust gas is easily affected by factors such as loading and unloading operations and cargo storage status and fluctuates. Therefore, by providing a pressure stabilizing valve 18, the pressure change is sensed in real time. When the pressure is too high, the valve opening is automatically increased to release the pressure, and when the pressure is too low, the valve opening is reduced to maintain the pressure, so as to ensure that the pressure of the exhaust gas entering the burner 6 is stable, maintain a stable combustion flame, avoid flameout, deflagration and other problems caused by large pressure fluctuations, ensure the safety and stability of the combustion process, and provide a stable heat source for the initial incineration of the ventilation exhaust gas.

[0068] In other embodiments, the output end of the first flue gas exhaust pipeline 4 is connected to an external decarbonization and desulfurization system, and the output end of the second flue gas exhaust pipeline 8 is connected to the first flue gas exhaust pipeline 4 and the external atmosphere, respectively.

[0069] The second smoke exhaust pipeline 8 is provided with a concentration detector 19 for detecting the concentration of the smoke exhausted from the second smoke exhaust pipeline 8 and selectively outputting the smoke to the first smoke exhaust pipeline 4 or the external atmosphere according to the detection result.

[0070] Specifically, by setting up a concentration detector 19, when the concentration of the flue gas discharged from the second flue gas exhaust pipeline 8 is high, the flue gas can be automatically output to the first flue gas exhaust pipeline 4, and enter the external decarbonization and desulfurization system together with the engine flue gas for deep treatment to ensure the exhaust gas treatment effect; when the concentration of the flue gas discharged from the second flue gas exhaust pipeline 8 is low and meets the emission standards, the flue gas can be directly output to the external atmosphere, reducing the load of the decarbonization and desulfurization system, and reducing energy consumption and costs.

[0071] In summary, compared with the prior art, the ship exhaust comprehensive treatment system proposed in this embodiment has at least the following technical effects: Through the close cooperation between the engine flue gas treatment subsystem and the cabin exhaust gas treatment subsystem, classified centralized treatment of various ship exhaust gases can be achieved. Specifically, the ozone generator 1 in the engine flue gas treatment subsystem generates ozone, which is transported to the ventilation exhaust gas discharge pipeline 11 of the cabin exhaust gas treatment subsystem through a branch pipeline, and is fully mixed with the ventilation exhaust gas in the exhaust gas-ozone mixer 12. This not only provides a key oxidant for cabin exhaust gas treatment, but also enables the ventilation exhaust gas to be more effectively treated in the subsequent burner 6 and the second catalytic oxidation reactor 7; and in the cabin exhaust 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, increasing the mixing 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 exhaust gas treatment efficiency and reducing pollutant emissions.

[0072] In addition, by using ozone as the main oxidant and utilizing the property of ozone to decompose and produce active oxygen atoms at relatively low temperatures (200℃-300℃), there is no need for additional heating equipment to significantly increase the flue gas temperature, thus reducing energy consumption and cost increases.

[0073] In addition, an exhaust gas analysis pipeline 13 is provided to introduce the exhaust gas analysis generated by the ship's PSA nitrogen generator into the ozone generator 1 as a raw material for synthesizing ozone, thereby realizing the resource recycling of exhaust gas, reducing dependence on external gas sources, reducing the cost of obtaining ozone raw materials, and avoiding the impact of exhaust gas emissions on the environment. Finally, the discharged exhaust gas is used as fuel for the burner 6, realizing the resource utilization of the discharged exhaust gas, reducing exhaust gas emissions, reducing the ship's dependence on external fuels, and saving operating costs.

[0074] Example 2

[0075] This embodiment 2 proposes a ship exhaust gas treatment process. Compared with the method of separately configuring treatment equipment for different exhaust gases in the prior art, this process achieves the functions of comprehensive coverage, comprehensive treatment and efficient energy utilization of ship exhaust gas.

[0076] The ship exhaust gas includes engine smoke and cabin exhaust gas including discharge exhaust gas and ventilation exhaust gas.

[0077] The ship exhaust gas treatment process specifically comprises the following steps: Ozone is generated by the ozone generator 1. By using ozone as the main oxidant and utilizing the property of ozone to decompose and produce active oxygen atoms at relatively low temperatures (200°C-300°C), there is no need for additional heating equipment that significantly increases the flue gas temperature, thus reducing energy consumption and cost increases.

[0078] The engine smoke generated in the ship engine and the ozone are evenly mixed in a predetermined ratio in the smoke-ozone mixer 2 to form a smoke-ozone mixed gas. The ozone in the smoke-ozone mixed gas is catalytically decomposed by the first catalytic oxidation reactor 3 to form active oxygen atoms. The methane or ammonia in the smoke-ozone mixed gas is oxidized and decomposed by the active oxygen atoms and the catalytic action of the first catalytic oxidation reactor 3, and discharged to the first smoke exhaust pipeline 4, that is, the treatment effect of the engine smoke is improved through a double reaction mechanism.

[0079] The ventilation exhaust gas and the ozone are mixed evenly in a predetermined ratio in the exhaust gas-ozone mixer 12 to form an exhaust gas-ozone mixed gas, and part of the methane or ammonia in the exhaust gas-ozone mixed 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, and the unincinerated part of the methane or ammonia is oxidized and decomposed with the help of the active oxygen atoms and the second catalytic oxidation reactor 7, and discharged to the second flue gas exhaust pipeline 8. The treatment method of combining ozone with the second catalytic oxidation reactor 7 makes it unnecessary to maintain a high-temperature combustion environment like the RTO device, so there is no need to equip a large heat storage structure and a complex gas supply system, so the volume occupied by the overall system can be effectively reduced, achieving the purpose of occupying a small space and being easy to install and apply.

[0080] The discharged waste gas is input into the burner 6 to provide a fuel source for the burner 6, thereby achieving full utilization of the discharged waste gas and avoiding waste of resources.

[0081] In this embodiment, the second flue gas exhaust 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, thereby improving energy utilization.

[0082] Specifically, the ship exhaust gas treatment process also includes the following steps: 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, and by increasing the reaction temperature of the flue gas-ozone mixer 2, the rate at which ozone decomposition produces active oxygen atoms can be accelerated, while the reaction activity of active oxygen atoms with pollutants such as methane and ammonia is enhanced), the output power of the burner 6 is increased, and the gas discharged from the second flue gas exhaust pipeline 8 is controlled 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, so as to ensure the exhaust gas treatment effect while improving the energy utilization rate.

[0083] In other embodiments, the ship exhaust gas treatment process further comprises the following steps: The analyzed waste gas generated by the ship's PSA nitrogen generator is input into the ozone generator 1 to generate ozone, so as to realize the function of waste gas resource reuse.

[0084] In a further embodiment, a bypass pipeline 15 is connected between the flue gas-ozone mixer 2 and the first flue gas exhaust pipeline 4 to increase the processing rate and reduce energy consumption.

[0085] Specifically, the ship exhaust gas treatment process also includes the following steps: The concentration of methane or ammonia in the flue gas-ozone mixed gas output by the flue gas-ozone mixer 2 is detected, and a detection result is generated.

[0086] If the detection result is greater than a set threshold, the flue gas-ozone mixed gas is controlled to pass through the first catalytic oxidation reactor 3, and is discharged from the first flue gas exhaust pipeline 4 after the oxidation decomposition is completed.

[0087] If the detection result is less than the set threshold, the flue gas-ozone mixed gas is controlled to pass through the bypass pipeline 15, and the ozone in the flue gas-ozone mixed gas is used to complete the oxidation decomposition of methane or ammonia, and after the oxidation decomposition is completed, it is discharged from the first flue gas exhaust pipeline 4.

[0088] That is, when the gas concentration detection sensor 14 detects that the concentration of ammonia or methane 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, so the gas output from the flue gas-ozone mixer 2 can be directly entered into the first flue gas exhaust pipeline 4 through the bypass pipeline 15, thereby avoiding unnecessary treatment processes of the gas in the first catalytic oxidation reactor 3, thereby improving treatment efficiency and reducing energy consumption. When a high concentration of ammonia or methane is detected, the gas passes through the first catalytic oxidation reactor 3, and the active oxygen atoms generated by the decomposition of the catalyst and 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.

[0089] In summary, compared with the prior art method of separately configuring treatment equipment for different exhaust gases, the ship exhaust gas treatment process described in this embodiment achieves the functions of comprehensive coverage, comprehensive treatment and efficient energy utilization of ship exhaust gas.

[0090] 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 their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A comprehensive ship exhaust gas treatment system, characterized in that: Includes engine smoke treatment subsystem and cabin exhaust gas treatment subsystem; The engine smoke treatment subsystem includes an ozone generator, a smoke-ozone mixer, a first catalytic oxidation reactor and a first smoke exhaust pipeline connected in sequence; The input end of the flue gas-ozone mixer is connected to the engine flue gas exhaust pipeline; The cabin exhaust gas treatment subsystem includes a burner, a second catalytic oxidation reactor and a second flue gas exhaust pipeline connected in sequence; The input end of the burner is respectively connected to an air intake pipeline and a waste gas discharge pipeline; The input end of the second catalytic oxidation reactor is connected to a ventilation exhaust gas discharge pipeline; Wherein, 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.

2. The ship exhaust comprehensive treatment system according to claim 1, characterized in that: The second smoke exhaust pipeline is connected to the engine smoke exhaust pipeline through a first valve pipeline, and is used to increase the mixing reaction temperature of the engine smoke and ozone in the smoke-ozone mixer.

3. The ship exhaust comprehensive treatment system according to claim 1, characterized in that: The engine smoke treatment subsystem also includes an exhaust gas analysis pipeline; One end of the analytical waste gas pipeline is connected to the ship PSA nitrogen generator, and the other end is connected to the ozone generator, so as to provide a gas raw material source for the ozone generated by the ozone generator.

4. The ship exhaust comprehensive treatment system according to claim 1, characterized in that: A gas concentration detection sensor is provided at the input end of the first catalytic oxidation reactor for detecting the concentration of ammonia or methane; A bypass pipeline is connected between the flue gas-ozone mixer and the first flue gas exhaust 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.

5. The ship exhaust comprehensive treatment system according to claim 1, characterized in that: The first catalytic oxidation reactor and the second catalytic oxidation reactor are both filled with catalyst fillers; The catalyst filler is one or more of copper oxide, manganese oxide and titanium dioxide.

6. The ship exhaust comprehensive treatment system according to claim 1, characterized in that: Also included is a catalyst activation steam line; The output end of the catalyst activation steam pipeline is connected to the engine smoke exhaust pipeline and the ventilation exhaust gas exhaust pipeline through a second valve pipeline, which is used to clean the carbon deposits formed by the smoke in the engine smoke exhaust pipeline and to purge the burner connected to the ventilation exhaust gas exhaust pipeline.

7. The ship exhaust comprehensive treatment system according to claim 1, characterized in that: The second catalytic oxidation reactor is provided with a heat exchange tube for recovering the residual heat of the flue gas after incineration.

8. The ship exhaust comprehensive treatment system according to claim 1, characterized in that: The ozone generator is a tubular arc ozone generator.

9. The ship exhaust comprehensive treatment system according to claim 1, characterized in that: A pressure stabilizing valve is arranged on the exhaust gas discharge pipeline.

10. The ship exhaust comprehensive treatment system according to claim 1, characterized in that: The output end of the first flue gas exhaust pipeline is connected to an external decarbonization and desulfurization system, and the output end of the second flue gas exhaust pipeline is connected to the first flue gas exhaust pipeline and the external atmosphere respectively; The second smoke exhaust pipeline is provided with a concentration detector for detecting the concentration of the smoke exhausted from the second smoke exhaust pipeline, and selectively outputting the smoke to the first smoke exhaust pipeline or the external atmosphere according to the detection result.

11. A ship exhaust gas treatment process, characterized in that: The ship exhaust gas includes engine smoke and cabin exhaust gas including discharge exhaust gas and ventilation exhaust gas, and specifically includes the following steps: Ozone is generated by an ozone generator; The engine smoke generated in the ship engine and the ozone are uniformly mixed in a predetermined ratio in a smoke-ozone mixer to form a smoke-ozone mixed gas, the ozone in the smoke-ozone mixed gas is catalytically decomposed by a first catalytic oxidation reactor to form active oxygen atoms, and the methane or ammonia in the smoke-ozone mixed gas is oxidized and decomposed by the active oxygen atoms and the catalytic action of the first catalytic oxidation reactor, and discharged to a first smoke exhaust pipeline; The ventilation exhaust gas and the ozone are uniformly mixed in a predetermined ratio in an exhaust gas-ozone mixer to form an exhaust gas-ozone mixed gas, a part of the methane or ammonia in the exhaust gas-ozone mixed gas is incinerated by a burner, and at the same time, the second catalytic oxidation reactor catalytically decomposes the ozone to form active oxygen atoms, and the unincinerated part of the methane or ammonia is oxidized and decomposed by means of the active oxygen atoms and the second catalytic oxidation reactor, and discharged to the second flue gas exhaust pipeline; The exhaust gas is input into the burner to provide a fuel source for the burner.

12. The ship exhaust gas treatment process according to claim 11, characterized in that: The second smoke exhaust pipeline is connected to the input end of the smoke-ozone mixer; The ship exhaust gas treatment process also 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, the output power of the burner is increased, and the gas discharged from the second flue gas exhaust pipeline is controlled to flow back to the input end of the flue gas-ozone mixer, so as to increase the mixing reaction temperature of the engine flue gas and the ozone in the flue gas-ozone mixer.

13. The ship exhaust gas treatment process according to claim 11, characterized in that: The following steps are also included: The decomposed exhaust gas generated by the ship's PSA nitrogen generator is input into the ozone generator to generate ozone.

14. The ship exhaust gas treatment process according to claim 11, characterized in that: A bypass pipeline is connected between the flue gas-ozone mixer and the first flue gas exhaust pipeline; The ship exhaust gas treatment process also includes the following steps: Detecting the concentration of methane or ammonia in the flue gas-ozone mixed gas output by the flue gas-ozone mixer and generating a detection result; If the detection result is greater than the set threshold, the flue gas-ozone mixed gas is controlled to pass through the first catalytic oxidation reactor, and is discharged from the first flue gas exhaust pipeline after the oxidation and decomposition are completed; If the detection result is less than the set threshold, the flue gas-ozone mixed gas is controlled to pass through the bypass pipeline, and the ozone in the flue gas-ozone mixed gas is used to complete the oxidation decomposition of methane or ammonia, and after the oxidation decomposition is completed, it is discharged from the first flue gas exhaust pipeline.

Images