Ship diesel engine tail gas treatment device

Abstract

The utility model relates to the technical field of tail gas treatment, in particular to a ship diesel engine tail gas treatment device which comprises a supporting structure and is characterized in that a first supporting frame is arranged on one side of the top of the supporting structure, a second supporting frame is arranged on one side of the first supporting frame, and a third supporting frame is arranged on one side of the second supporting frame. A black smoke removing device is installed at the top of the first supporting frame, a heating device is installed at the top of the second supporting frame, an SCR reactor is installed at the top of the third supporting frame, one end of the SCR reactor is connected with a discharging pipeline, and a urea spraying device is arranged between the black smoke removing device and the heating device. Through cooperative work of the black smoke removal device, the heating device, the SCR reactor and the ammonia escape catalyst, the NOx removal rate is larger than or equal to 95%, and international environmental protection standards such as MARPOLANnexVI are met; the device adopts a supporting structure and modular components (such as a black smoke removing device, a heating device and an SCR reactor), is convenient to transport, mount and maintain, and reduces the construction difficulty and cost.

Description

TECHNICAL FIELD

[0001] The utility model relates to a tail gas treatment technical field, especially a ship berth diesel engine tail gas treatment device. BACKGROUND

[0002] The ship diesel engine tail gas contains a large amount of nitrogen oxide (NOx), particulate matter (PM) and sulfur oxide (SOx), which causes serious harm to the atmospheric environment and human health. The International Maritime Organization (IMO) has put forward strict restrictions on ship exhaust emissions through MARPOL Annex VI regulations.

[0003] The prior art has certain limitations, wet desulfurization technology: although it can effectively remove SOx, but the removal effect of NOx is limited; selective catalytic reduction (SCR) technology: widely used in land industry, but there are problems such as limited installation space and insufficient corrosion resistance on ships; ammonia escape problem: the ammonia gas not completely consumed after SCR reaction may escape to the atmosphere, causing secondary pollution. Therefore, it is an urgent need in the industry to develop a high-efficiency denitration, compact structure, strong corrosion resistance and ship working condition adaptive tail gas treatment device.

[0004] Chinese patent discloses a diesel engine tail gas treatment device (publication number: CN 211116195 U) including a shell, one end of the shell is the air inlet end, the other end of the shell is the air outlet end, the shell is provided with POC treatment layer, DOC treatment layer and DPF treatment layer in the direction from the air inlet end to the air outlet end, but this kind of diesel engine tail gas treatment device, therefore, a ship berth diesel engine tail gas treatment device is needed. UTILITY MODEL CONTENT

[0005] The utility model aims at solving the shortcomings that the existing diesel engine tail gas treatment device has poor NOx removal effect, limited installation space, insufficient corrosion resistance, ammonia escape problem, high energy consumption and poor economy, and cannot fully meet the environmental protection and operation requirements of the ship industry, and proposes a ship berth diesel engine tail gas treatment device.

[0006] The utility model solves its technical problem adopts the technical scheme: A kind of ship park diesel engine tail gas treatment device described in the utility model, including support structure, it is characterized by: the support structure is made of several connecting cross beams combination, first support frame is equipped in the top side of the support structure, second support frame is equipped in the one side of the first support frame, third support frame is equipped in the one side of the second support frame, black smoke removal device is installed at the top of the first support frame, heating device is installed at the top of the second support frame, SCR reactor is installed at the top of the third support frame, the one end of the SCR reactor is connected with discharge pipeline, urea injection device is equipped between black smoke removal device and heating device, urea metering pump is equipped between heating device and SCR reactor, first coupling is equipped between the urea metering pump and the SCR reactor, catalytic pre-mixing chamber is installed at the top of the first coupling, conveying pipeline is connected in the one end of the catalytic pre-mixing chamber, the other end of the conveying pipeline is matched with discharge pipeline.Support structure installs each component in subarea, it is convenient to transport, installation and maintenance;Each component is arranged according to process flow sequence, to ensure that tail gas treatment efficiency maximization;Connecting cross beam and support frame structure are stable, adapt to ship vibration environment;Urea injection, heating, mixing and catalytic reaction closely link, reduce energy loss and equipment volume.

[0007] Preferably, the top of the SCR reactor is provided with a catalytic reaction chamber, the bottom of the catalytic reaction chamber is provided with a trapezoidal support, the number of the trapezoidal supports is two and they are correspondingly arranged, and the side of the catalytic reaction chamber is provided with a flow control valve. The catalytic reaction chamber contains honeycomb catalyst, which increases the contact area and improves the denitration efficiency. The trapezoidal support enhances the bearing capacity and adapts to the vibration and inclination conditions of the ship. The flow control valve accurately adjusts the flow of the tail gas to ensure the stability of the catalytic reaction conditions.

[0008] Preferably, the middle section of the conveying pipeline is provided with a second coupling, and the top of the second coupling is provided with an ammonia slip catalyst. The ammonia slip catalyst decomposes unreacted residual ammonia gas to avoid secondary pollution. The second coupling ensures the close connection between the conveying pipeline and the ammonia slip catalyst to prevent leakage. The coupling is designed to facilitate the disassembly and replacement of the ammonia slip catalyst.

[0009] Preferably, the urea injection device includes a spray inlet pipe, one end of the spray inlet pipe is provided with a connecting pipe, one end of the connecting pipe is associated with the black smoke removal device, and the other end is associated with the heating device. The spray inlet pipe ensures that the urea solution is uniformly sprayed into the tail gas to avoid local over-concentration or under-concentration. The spray device is directly connected with the front and rear equipment to reduce the length of the pipeline and the pressure drop loss. The spray inlet pipe is made of corrosion-resistant material (such as 316L stainless steel) to prolong the service life.

[0010] Preferably, the SCR reactor comprises a box body, one side of the box body is provided with a sealing box cover plate, the sealing box cover plate is provided with fixing bolts, the number of the fixing bolts is 10-20, the center of the sealing box cover plate is provided with a pull ring, and the top of the box body is provided with four lifting rings which are correspondingly arranged. The sealing box cover plate and the fixing bolts ensure the air tightness of the box body and prevent tail gas leakage; the pull ring and the lifting ring are designed to facilitate disassembly and hoisting, thereby improving the maintenance efficiency; the fixing bolts are uniformly distributed, thereby enhancing the overall strength of the box body and adapting to the ship vibration environment.

[0011] Preferably, the material of the exhaust pipeline is 2205 duplex stainless steel. The 2205 duplex stainless steel is resistant to sulfide, ammonia and chloride corrosion and is suitable for marine environment; the duplex stainless steel has high strength and toughness, thereby ensuring stable operation of the pipeline under high pressure and vibration conditions; the material has high durability, thereby reducing replacement and maintenance costs.

[0012] The utility model has the advantages that:

[0013] The application realizes that the removal rate of NOx is greater than or equal to 95% through the cooperative work of the black smoke removal device, the heating device, the SCR reactor and the ammonia escape catalyst, and meets international environmental protection standards such as MARPOL Annex VI; the device adopts a support structure and modular components (such as the black smoke removal device, the heating device and the SCR reactor), thereby facilitating transportation, installation and maintenance, reducing construction difficulty and cost; the support structure adopts a connecting cross beam and a trapezoidal support, thereby ensuring the stability of the device under complex working conditions such as ship vibration and inclination; the urea injection device and the flow control valve realize accurate control of the flow of urea solution and tail gas, thereby avoiding the problems of increased energy consumption and ammonia escape caused by excessive injection; the key components (such as the exhaust pipeline and the injection access pipe) are made of 2205 duplex stainless steel or 316L stainless steel, are resistant to corrosion and high temperature, are suitable for marine environment and prolong the service life; the ammonia escape catalyst decomposes residual ammonia gas that has not reacted, thereby avoiding secondary pollution caused by ammonia gas emission and ensuring environmental protection compliance; the components are closely arranged according to the process flow, thereby reducing the length of the pipeline and the volume of the equipment and being suitable for installation on ships with limited space. BRIEF DESCRIPTION OF DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the utility model or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or the prior art description, and obviously, the drawings in the following description are only some embodiments of the utility model, and for those skilled in the art, other drawings can also be obtained according to these drawings without creative labor.

[0015] Figure 1 It is a structural schematic diagram of the utility model.

[0016] Figure 2This is a top view of the structure of this utility model.

[0017] Figure 3 This is a schematic diagram of the main structure of this utility model.

[0018] Figure 4 This is a schematic diagram of the right-side structure of this utility model.

[0019] In the diagram: 1. Black smoke removal device; 2. Urea injection device; 3. Heating device; 4. Urea metering pump; 5. Pre-catalytic mixing chamber; 6. Delivery pipeline; 7. Catalytic reaction chamber; 8. Ammonia escape catalyst; 9. SCR reactor; 10. Discharge pipeline; 11. Flow control valve; 12. Trapezoidal support; 13. Connecting pipe; 14. Injection inlet pipe; 15. First support frame; 16. Support structure; 17. Connecting beam; 18. Second support frame; 19. First coupling; 20. Sealing box cover; 21. Fixing bolt; 22. Pull ring; 23. Third support frame; 24. Box body; 25. Second coupling. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model. Example

[0021] Please see Figures 1-4As shown, a marine diesel engine exhaust gas treatment device includes a support structure 16, characterized in that: the support structure 16 is composed of several connecting beams 17, a first support frame 15 is provided on one side of the top of the support structure 16, a second support frame 18 is provided on one side of the first support frame 15, a third support frame 23 is provided on one side of the second support frame 18, a black smoke removal device 1 is installed on the top of the first support frame 15, a heating device 3 is installed on the top of the second support frame 18, an SCR reactor 9 is installed on the top of the third support frame 23, one end of the SCR reactor 9 is connected to an exhaust pipe 10, a urea injection device 2 is provided between the black smoke removal device 1 and the heating device 3, a urea metering pump 4 is provided between the heating device 3 and the SCR reactor 9, a first coupling 19 is provided between the urea metering pump 4 and the SCR reactor 9, a pre-catalytic mixing chamber 5 is installed on the top of the first coupling 19, one end of the pre-catalytic mixing chamber 5 is connected to a conveying pipe 6, and the other end of the conveying pipe 6 is connected to the exhaust pipe 10. The supporting structure is divided into 16 sections for installing various components, facilitating transportation, installation, and maintenance; the components are arranged in the order of the process flow to ensure maximum exhaust gas treatment efficiency; the connecting beam 17 and the support frame structure are stable and adaptable to the ship's vibration environment; urea injection, heating, mixing, and catalytic reaction are closely integrated to reduce energy loss and equipment volume.

[0022] In this embodiment, the SCR reactor 9 has a catalytic reaction chamber 7 at its top and a trapezoidal support 12 at its bottom. Two trapezoidal supports 12 are arranged correspondingly. A flow control valve 11 is located on one side of the catalytic reaction chamber 7. The catalytic reaction chamber 7 accommodates a honeycomb catalyst, increasing the contact area and improving denitrification efficiency. The trapezoidal support 12 enhances load-bearing capacity and adapts to ship vibration and tilting conditions. The flow control valve 11 precisely regulates the exhaust gas flow rate to ensure stable catalytic reaction conditions.

[0023] In this embodiment, a second coupling 25 is provided in the middle section of the conveying pipeline 6, and an ammonia escape catalyst 8 is provided at the top of the second coupling 25. The ammonia escape catalyst 8 decomposes unreacted residual ammonia gas to avoid secondary pollution. The second coupling 25 ensures that the conveying pipeline 6 and the ammonia escape catalyst 8 are tightly connected to prevent leakage. The coupling is designed to facilitate the disassembly and replacement of the ammonia escape catalyst 8.

[0024] In this embodiment, the urea injection device 2 includes an injection inlet pipe 14, one end of which is connected to a connecting pipe 13. One end of the connecting pipe 13 is associated with the black smoke removal device 1, and the other end is associated with the heating device 3. The injection inlet pipe 14 ensures that the urea solution is evenly injected into the exhaust gas, avoiding excessively high or low local concentrations; the injection device is directly connected to the upstream and downstream equipment, reducing pipe length and pressure drop loss; the injection inlet pipe 14 is made of corrosion-resistant material (such as 316L stainless steel), extending its service life.

[0025] In this embodiment, the SCR reactor 9 includes a housing 24. A sealing cover 20 is provided on one side of the housing 24. The sealing cover 20 is provided with 10-20 fixing bolts 21. A pull ring 22 is provided at the center of the sealing cover 20. Four lifting rings are provided at the top of the housing 24 and are correspondingly arranged. The sealing cover 20 and the fixing bolts 21 ensure the airtightness of the housing 24, preventing exhaust gas leakage. The pull rings 22 and lifting rings are designed for easy disassembly and hoisting, improving maintenance efficiency. The evenly distributed fixing bolts 21 enhance the overall strength of the housing 24, adapting to the vibration environment of ships.

[0026] In this embodiment, the discharge pipe 10 is made of 2205 duplex stainless steel. 2205 duplex stainless steel is a common product on the market and can be purchased directly. It is resistant to corrosion from sulfides, ammonia, and chlorides, making it suitable for marine environments. Duplex stainless steel combines high strength and toughness, ensuring stable operation of the pipeline under high pressure and vibration conditions. Its high durability reduces replacement and maintenance costs.

[0027] The implementation principle of this embodiment is as follows: when exhaust gas is discharged from the diesel engine, it first enters the black smoke removal device 1.

[0028] In the black smoke removal device 1, the exhaust gas passes through a filter medium (such as ceramic fiber or metal filter screen) to filter out particulate matter (PM, i.e., black smoke), protecting downstream equipment from blockage or damage. After the exhaust gas leaves the black smoke removal device 1, it enters the urea injection device 2. In the urea injection device 2, a 32.5% concentration urea solution is injected into the exhaust gas flow through the injection inlet pipe 14. The urea decomposes at high temperature to generate ammonia (NH3). After the exhaust gas and ammonia are mixed, they enter the pre-catalytic mixing chamber 5. In the pre-catalytic mixing chamber 5, the mixture is forcibly mixed by a rotor or guide plate to ensure that the ammonia and exhaust gas are evenly distributed, preparing for the subsequent catalytic reaction.

[0029] After the mixed gas leaves the pre-catalytic mixing chamber 5, it enters the heating device 3. In the heating device 3, the tail gas is heated to 200-400℃ (this is the optimal temperature range for the SCR reaction) to ensure that the catalytic reaction can proceed efficiently. After the tail gas is heated, it enters the SCR reactor 9 (installed on the third support frame 23). In the SCR reactor 9, the tail gas passes through the catalytic reaction chamber 7 (located at the top of the SCR reactor 9). Under the action of the catalyst (such as V2O5-WO3 / TiO2), ammonia and NOx undergo a reduction reaction to generate nitrogen (N2) and water (H2O), thereby removing NOx from the tail gas.

[0030] After the exhaust gas passes through the catalytic reaction chamber 7, it enters the conveying pipe 6 (connected to the ammonia escape catalyst 8 via the second coupling 25). After leaving the SCR reactor 9, the exhaust gas enters the ammonia escape catalyst 8 (installed in the middle section of the conveying pipe 6). In the ammonia escape catalyst 8, any unconsumed residual ammonia is decomposed, preventing secondary pollution from ammonia emissions into the atmosphere. After treatment by the ammonia escape catalyst 8, the exhaust gas is discharged into the atmosphere through the emission pipe 10 (made of 2205 duplex stainless steel). Throughout the emission process, the corrosion resistance and high strength of the emission pipe 10 ensure safe and stable emission of the exhaust gas, while meeting environmental standards.

[0031] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0032] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model.

Claims

1. A marine diesel engine exhaust gas treatment device, comprising a support structure (16), characterized in that: The support structure (16) is composed of several connecting beams (17). A first support frame (15) is provided on one side of the top of the support structure (16), a second support frame (18) is provided on one side of the first support frame (15), and a third support frame (23) is provided on one side of the second support frame (18). A black smoke removal device (1) is installed on the top of the first support frame (15), a heating device (3) is installed on the top of the second support frame (18), and an SCR reactor (9) is installed on the top of the third support frame (23). One end of the device is connected to an exhaust pipe (10). A urea injection device (2) is provided between the black smoke removal device (1) and the heating device (3). A urea metering pump (4) is provided between the heating device (3) and the SCR reactor (9). A first coupling (19) is provided between the urea metering pump (4) and the SCR reactor (9). A pre-catalytic mixing chamber (5) is installed on the top of the first coupling (19). One end of the pre-catalytic mixing chamber (5) is connected to a conveying pipe (6). The other end of the conveying pipe (6) is connected to the exhaust pipe (10).

2. The marine diesel engine exhaust gas treatment device according to claim 1, characterized in that: The SCR reactor (9) is provided with a catalytic reaction chamber (7) at the top and a trapezoidal support (12) at the bottom of the catalytic reaction chamber (7). There are two trapezoidal supports (12) and they are arranged in a corresponding manner. A flow control valve (11) is provided on one side of the catalytic reaction chamber (7).

3. The exhaust gas treatment device for marine diesel engines according to claim 1, characterized in that: The middle section of the conveying pipeline (6) is provided with a second coupling (25), and the top of the second coupling (25) is provided with an ammonia escape catalyst (8).

4. The exhaust gas treatment device for marine diesel engines according to claim 1, characterized in that: The urea injection device (2) includes an injection inlet pipe (14), one end of which is provided with a connecting pipe (13). One end of the connecting pipe (13) is associated with the black smoke removal device (1), and the other end is associated with the heating device (3).

5. The exhaust gas treatment device for marine diesel engines according to claim 1, characterized in that: The SCR reactor (9) includes a box (24), a sealing box cover (20) is provided on one side of the box (24), a fixing bolt (21) is provided on the sealing box cover (20), the number of fixing bolts (21) is 10 to 20, a pull ring (22) is provided in the center of the sealing box cover (20), and a lifting ring is provided on the top of the box (24), the number of lifting rings is 4 and they are set accordingly.

6. The exhaust gas treatment device for marine diesel engines according to claim 1, characterized in that: The discharge pipe (10) is made of 2205 duplex stainless steel.

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