Train loading exhaust gas absorption device and absorption method

Abstract

This invention discloses an absorption device and method for train loading exhaust gas, comprising an air supply device, an oil conveying device, an oil-gas dehydrator, a diesel absorption tower, a diesel dehydrator, a decontamination oil tank, and an oil discharge device. The air supply device is connected to the oil-gas dehydrator for dehydrating the train loading exhaust gas. The exhaust port of the oil-gas dehydrator is connected to the diesel absorption tower for purifying and absorbing the train loading exhaust gas. The inlet of the diesel absorption tower is connected to the oil conveying device for conveying diesel fuel. The exhaust port of the diesel absorption tower is connected to an RTO (Regenerative Thermal Oxidizer) device for further processing the purified gas. A diesel outlet is provided at the bottom of the diesel absorption tower, connected to the diesel dehydrator for dehydrating the diesel fuel. This device is characterized by high efficiency, low initial investment cost, small size, easy maintenance, and low operating costs, resulting in significant economic benefits. The absorption method of this device enables high-precision absorption and effectively solves the problem of mist entrainment in the outlet gas.

Description

Technical Field

[0001] This invention relates to the field of train loading exhaust gas absorption and treatment technology, specifically to an absorption device and method for train loading exhaust gas. Background Technology

[0002] In recent years, with the acceleration of urbanization and the increase in transportation demand, train transportation has become one of the important modes of passenger and freight transportation. However, the environmental problems caused by train loading exhaust emissions have become increasingly prominent, and volatile organic compounds (VOCs), the main component of train loading exhaust, have gradually come into people's view.

[0003] Compared to traditional gaseous pollutants such as sulfur dioxide, VOCs have a more complex composition and variety. They include hydrocarbons, esters, aldehydes, etc., with hydrocarbons further including alkanes, alkenes, and aromatic hydrocarbons. VOCs have an unpleasant and irritating odor, which can damage the human respiratory system to some extent, cause damage to the central nervous system, and lead to memory loss. In addition, VOCs contain some carcinogenic, teratogenic, and mutagenic chemicals.

[0004] In recent years, policies have placed increasing emphasis on VOCs control. Numerous standards and regulations have been introduced, including the "Guidelines for VOCs Pollution Source Investigation in Petrochemical Enterprises," the "Emission Standards for Pollutants from Petrochemical Industry," and the "Emission Standards for Pollutants from Petroleum Refining Industry." These standards and regulations impose stricter requirements on the emission control of air pollutants from petrochemical enterprises, making the control task increasingly challenging. This has also spurred a huge market for VOCs control and a wide variety of VOCs treatment technologies.

[0005] Currently, VOCs treatment methods in the market can be simply divided into two main aspects: source control and end-of-pipe treatment.

[0006] Enterprises control emissions at their source by adjusting production technologies, upgrading equipment, and standardizing and refining operations. While controlling VOCs at their source, some essential VOCs (volatile organic compounds) emissions need to be treated at the end of the line.

[0007] Currently, end-of-pipe treatment technologies are mainly divided into two categories: recovery technologies and disposal technologies. Recovery technologies achieve emission reduction and treatment by recovering VOCs gases, and methods include condensation, absorption, adsorption, and membrane separation. Disposal technologies decompose and convert VOCs gases into non-toxic and harmless substances through chemical methods such as combustion or biochemical reactions such as microbial reactions before re-emission, including combustion and biodegradation. However, each technology has difficulty effectively treating the complex exhaust gases from train loading. Summary of the Invention

[0008] The purpose of this invention is to provide an absorption device and method for the exhaust gas of train loading. The device is highly efficient, has low initial investment cost, small size, is easy to maintain, and has low operating costs, which can generate huge economic benefits. The absorption method of the device can perform high-precision absorption and can effectively solve the problem of mist entrainment in the outlet gas.

[0009] The technical solution adopted by this invention to solve its technical problem is: a train loading exhaust gas absorption device, the structure of which includes an air supply device, an oil supply device, an oil-gas dehydrator, a diesel absorption tower, a diesel dehydrator, a decontamination oil tank, an oil discharge device, and a decontamination oil tank. The air supply device is connected to the oil-gas dehydrator for dehydrating the train loading exhaust gas. The outlet of the oil-gas dehydrator is connected to the decontamination oil tank for treating the dehydrated liquid. The exhaust port of the oil-gas dehydrator is connected to the diesel absorption tower for purifying and absorbing the train loading exhaust gas. The inlet of the diesel absorption tower is connected to the oil supply device for transporting diesel fuel. The exhaust port of the diesel absorption tower is connected to an RTO device for further processing the purified gas. The outlet of the diesel absorption tower is connected to the diesel dehydrator through a pipeline, and the outlet of the diesel dehydrator is connected to the decontamination oil tank through a pipeline.

[0010] Furthermore, the gas supply device includes a second heat exchanger, and the exhaust gas is fed into the oil-gas dehydrator after being heated by the second heat exchanger.

[0011] Furthermore, the oil-gas dehydrator includes an oil-gas dehydrator shell, a rotary jet absorber, a flow distribution module one, a train loading exhaust gas inlet, an exhaust port, a demisting module, and a partition plate; a downcomer and a drain port. The downcomer is located inside the shell, the demisting module is located in the upper part of the inner cavity of the oil-gas dehydrator shell, and a partition plate is provided in the upper and lower parts of the inner cavity of the oil-gas dehydrator shell. A flow distribution module is located above the partition plate in the lower part of the inner cavity of the oil-gas dehydrator shell, and a rotary jet absorber is located above the flow distribution module one. The drain port is located at the lower end of the oil-gas dehydrator shell, the exhaust port is located at the upper end of the oil-gas dehydrator shell, and the train loading exhaust gas inlet is located on one side of the oil-gas dehydrator shell and corresponds to the flow distribution module one.

[0012] Furthermore, the defogging module includes a corrugated baffle module and a fiber condensation module, which are respectively connected to the inner wall of the housing through a fixed module assembly.

[0013] Furthermore, the diesel absorption tower includes a diesel absorption tower shell, a diesel inlet, a swirl jet absorber, a flow distribution module II, a gas inlet to be treated, a purified gas outlet, a corrugated baffle module, a fiber condensation module, a partition plate, a downcomer, and a drain outlet. The diesel absorption tower shell is arranged from top to bottom with the corrugated baffle module, the fiber condensation module, the swirl jet absorber, the flow distribution dewatering module, a partition plate for fixing the modules, and a downcomer connected to the partition plate. The diesel inlet is located on one side of the shell. The upper end of the diesel absorption tower shell has a purified gas outlet, and the lower end of the diesel absorption tower shell has a drain outlet. The gas inlet to be treated is located in the lower middle part of one side of the diesel absorption tower shell and corresponds to the flow distribution dewatering module.

[0014] Furthermore, the swirl jet absorber includes a swirl jet absorber shell, a gas inlet to be treated, a jacket, an overflow pipe, and a swirl jet drain port. The jacket is fitted outside the swirl jet absorber shell, and a cavity structure capable of accommodating diesel fuel is formed between the inner surface of the jacket and the outer surface of the cylinder. The overflow pipe is located in the upper part of the inner cavity of the swirl jet absorber shell, and a swirl jet drain port is provided at the lower end of the swirl jet absorber shell.

[0015] Furthermore, the diesel dehydrator includes a diesel dehydrator shell, a diesel inlet, a coarse fiber module, a corrugated baffle module, a fiber coagulation module, a diesel outlet, a fixed module assembly, and a drain port. The coarse fiber module, corrugated baffle module, and fiber coagulation module are arranged sequentially from left to right within the inner cavity of the diesel dehydrator shell. The corrugated baffle module and fiber coagulation module are respectively connected to the inner wall of the diesel dehydrator shell via the fixed module assembly. The diesel inlet is located at the left end of the diesel dehydrator shell, and a diesel outlet is located on the upper side of one side of the diesel dehydrator shell, while a drain port is located on the lower side.

[0016] Furthermore, the oil conveying device includes a heat exchanger and a refrigeration unit. The heat exchanger and the refrigeration unit are connected by a pipeline. The output end of the refrigeration unit is connected to the diesel absorption tower by a pipeline. The diesel fuel is fed into the diesel absorption tower after heat exchange by the heat exchanger and cooling by the refrigeration unit.

[0017] The absorption method of the exhaust gas absorption device for train loading includes the following steps:

[0018] S01, Oil and Gas Dehydration: The exhaust gas from the train loading is input into the oil and gas dehydrator and undergoes initial dehydration through the flow distribution module. The gas rises and is blocked by the partition plate before entering the swirl jet absorber for secondary dehydration. After passing through the overflow pipe of the swirl jet absorber, the gas is initially separated by impact from the top buffer cap. Subsequently, the rising gas enters the corrugated baffle module and the fiber condensation module for deep separation. The droplets gradually accumulate in the modules and flow into the liquid accumulation area at the bottom of the shell through the downcomer for discharge. The dehydrated gas then enters the diesel absorption tower.

[0019] S02, Diesel Absorption: The gas to be treated after dehydration by the oil-gas dehydrator is input into the diesel absorption tower and undergoes initial dehydration via the flow distribution module. Simultaneously, diesel enters the diesel absorption tower and is transported to the jacket of the rotary jet absorber through the distribution pipe. The gas rises and is blocked by the partition plate before entering the rotary jet absorber and fully mixing with the diesel for three-stage micro-interface oscillation absorption. Droplets fall along the liquid leg of the rotary jet absorber into the liquid accumulation area at the bottom of the shell. After passing through the overflow pipe of the rotary jet absorber, the gas undergoes initial separation by impact from the top buffer cap. Subsequently, the rising gas enters the corrugated baffle module and fiber condensation module for deep separation. Droplets gradually accumulate in the modules and are discharged from the equipment via the downcomer into the liquid accumulation area at the bottom of the shell.

[0020] S03, Reuse and Emission: The purified gas discharged from the diesel absorption tower is sent to the RTO unit for further processing. The diesel collected at the bottom of the shell is transported to the diesel dehydrator for dehydration via the oil discharge device. The liquid flows into the discharge device at the bottom of the shell, and the dehydrated diesel is sent to the subsequent unit for dehydrogenation treatment.

[0021] The beneficial effects of this invention are:

[0022] The train exhaust gas absorption device provided by this invention has the following main advantages:

[0023] (1) The present invention adds an oil and gas dehydration process before the diesel absorption tower, thereby further reducing the liquid content of the final outlet gas and achieving secondary separation and dehydration, thereby improving the purification effect of the system.

[0024] (2) The diesel absorption tower of the present invention adopts swirl jet absorption technology. Compared with the two-phase flow pattern in traditional gas-liquid mass transfer equipment, there is a strong interaction phenomenon between liquid jet and gas swirl in this equipment. Under different operating conditions, the gas swirl field can transform the liquid jet from a steady jet to an atomized swirl jet, increasing the effective phase interface area for mass transfer between the gas and liquid phases; at the same time, due to the strong interaction between the two phases, the mass transfer coefficients of the gas film and liquid film are also improved, increasing the overall interphase mass transfer coefficient. Due to the increase in the relative velocity and shear force between the gas and liquid, as well as the increase in the effective phase interface area and mass transfer coefficient, the mass transfer efficiency is high, the equipment size is small, and it also has the advantages of simple structure, no internal moving parts, wide applicability, self-cleaning, and no fear of clogging and scaling.

[0025] (3) All internal modules of the train loading exhaust gas absorption device of the present invention are detachable, making them easy to clean or replace during maintenance.

[0026] (4) The train loading exhaust gas absorption device of the present invention has high reliability, is easy to maintain, produces no waste, and has extremely low operating costs.

[0027] The method for absorbing exhaust gases from trains provided by this invention has the following main advantages:

[0028] (1) The gas-liquid mass transfer method of the present invention transforms the liquid jet column into a large number of small droplets, thereby increasing the liquid phase surface area and surface renewal frequency in the mass transfer space, and greatly improving the gas-liquid mass transfer efficiency.

[0029] (2) The present invention adopts a flow distribution liquid removal method at the air inlet, and adopts a gas-liquid separation concept that combines centrifugation and gravity, which effectively realizes gas-liquid separation and gas distribution functions, can significantly reduce the volume of the current gas-liquid separator, enhance gas-liquid mass transfer, and can significantly suppress and eliminate the problem of mist entrainment.

[0030] (3) The train loading exhaust gas absorption method of the present invention can realize the recycling of diesel fuel and remove VOCs with high efficiency, so as to maximize the use of absorbent. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the structure of the train loading exhaust gas absorption device in a specific embodiment of the present invention;

[0032] Figure 2 This is a schematic diagram of the structure of the oil-gas dehydrator in a specific embodiment of the present invention;

[0033] Figure 3 This is a schematic diagram of the diesel absorption tower in a specific embodiment of the present invention;

[0034] Figure 4 This is a schematic diagram of the diesel dehydrator in a specific embodiment of the present invention;

[0035] Figure 5 This is a schematic diagram of the structure of the swirl-jet absorber in a specific embodiment of the present invention.

[0036] In the picture:

[0037] 1. Train loading exhaust gas; 2. Heat exchanger one; 3. Refrigerant; 4. Heat exchanger two;

[0038] 5. Oil-gas dehydrator; 501. Oil-gas dehydrator shell; 502. First swirl jet absorber; 503. Flow distribution module one; 504. Train loading exhaust gas inlet; 505. Exhaust port; 506. First corrugated baffle module; 507. First fiber condensation module; 508. First partition plate; 509. First downcomer; 510. First drain port;

[0039] 6. First decontamination oil tank;

[0040] 7. Diesel Absorption Tower; 701. Diesel Absorption Tower Shell; 702. First Diesel Inlet; 703. Second Swirl Jet Absorber; 7031. Swirl Jet Absorber Shell; 7032. First Gas Inlet; 7033. Jacket; 7034. Overflow Pipe; 7035. Swirl Jet Drain; 704. Flow Distribution Module II; 705. Second Gas Inlet; 706. Purified Gas Outlet; 707. Second Corrugated Baffle Module; 708. Second Fiber Coagulation Module; 709. Second Separator; 710. Second Downcomer; 711. Second Drain;

[0041] 8. Diesel dehydrator; 801. Diesel dehydrator housing; 802. Second diesel inlet; 803. Coarse fiber module; 804. Third corrugated baffle module; 805. Third fiber coagulation module; 806. Diesel outlet; 807. Fixed module assembly; 808. Third drain port;

[0042] 9. RTO unit; 10. Second degreased oil tank. Detailed Implementation

[0043] The following is a detailed description of an absorption device and method for absorbing exhaust gas from train loading, with reference to the accompanying drawings.

[0044] like Figures 1 to 5 As shown, the train loading exhaust gas absorption device proposed in this invention includes an air supply device, an oil supply device, an oil-gas dehydrator 5, a diesel absorption tower 7, a diesel dehydrator 8, a first decontamination oil tank 6, an oil discharge device, and a second decontamination oil tank 10. The air supply device is connected to the oil-gas dehydrator 5 for dehydrating the train loading exhaust gas 1. The outlet of the oil-gas dehydrator is connected to the first decontamination oil tank 6 for treating the dehydrated liquid. The exhaust port of the oil-gas dehydrator is connected to the diesel absorption tower 7 for purifying and absorbing the train loading exhaust gas 1. The inlet of the diesel absorption tower 7 is connected to the oil supply device for conveying diesel fuel. The exhaust port of the diesel absorption tower 7 is connected to an RTO device 9 for further processing the purified gas. The outlet of the diesel absorption tower 7 is connected to the diesel dehydrator 8 through a pipeline, and the outlet of the diesel dehydrator 8 is connected to the second decontamination oil tank 10 through a pipeline. The gas delivery device includes a heat exchanger 2 4, and the exhaust gas 1 from the train loading is fed into the oil-gas dehydrator after being heat exchanged by the heat exchanger 2.

[0045] The oil-gas dehydrator 5 includes an oil-gas dehydrator housing 501, a first rotary jet absorber 502, a flow distribution module 1 503, a train loading exhaust gas inlet 504, an exhaust port 505, a demisting module 508, a first partition plate 509, and a first downcomer 510. The first downcomer 509 is located inside the housing. The demisting module is located in the upper part of the inner cavity of the oil-gas dehydrator housing. The upper and lower parts of the inner cavity of the oil-gas dehydrator housing are respectively provided with first partition plates 508. The flow distribution module 1 503 is located above the partition plate in the lower part of the inner cavity of the oil-gas dehydrator housing. The first rotary jet absorber 502 is located above the flow distribution module 1. The first exhaust port 510 is located at the lower end of the oil-gas dehydrator housing. The exhaust port 505 is located at the upper end of the oil-gas dehydrator housing. The train loading exhaust gas inlet 504 is located on one side of the oil-gas dehydrator housing and corresponds to the flow distribution module 1.

[0046] The demisting module includes a first corrugated baffle module 506 and a first fiber condensation module 507, which are connected to the inner wall of the housing via fixed module assemblies. The first corrugated baffle module 506 comprises multiple layers of corrugated baffles arranged from bottom to top, using a lower surface that is oleophilic and an upper surface that is hydrophilic. When airflow carrying droplets enters the channel of the corrugated baffle module, the direction of airflow changes with the direction of the channel. Due to inertia, the droplets carried in the airflow do not change direction as easily as the airflow itself. The droplets collide with the baffles and adhere to their surface, forming a water film. This film moves forward with the airflow to a bend where it is separated. Its multi-baffle structure increases the chance of droplet capture. Unremoved droplets are captured at the next bend through the same process, and this repeated action greatly improves the demisting efficiency. The corrugated baffle is also equipped with a flushing system, which includes flushing pipes, flushing nozzles, flushing water pumps, automatic flushing water switching valves, pressure gauges, and flushing water flow meters. Its main function is to periodically flush away the liquid and solid deposits trapped on the corrugated baffle, keep the plates clean and moist, and prevent scale buildup on the blades and blockage of the channels.

[0047] The fiber condensation module is made of nanofibers woven from a mixture of metal wire mesh and Teflon, exhibiting excellent droplet capture performance. This nanofiber hybrid separator provides a large specific surface area, significantly improving the purity of liquid phase separation. When the gas flow carrying droplets enters the fiber condensation module, the gas first enters the coalescing layer with smaller pore diameters. The small droplets carried are intercepted and adsorbed by the fibers on the surface of the coalescing layer. As the gas flows forward, the small droplets are carried into deeper fibers, where they collide with other small droplets and coalesce into larger droplets. This coalescing process repeats continuously as the droplets move forward, continuously increasing the pore diameter of the coalescing layer and the diameter of the droplets. When the weight of the droplet exceeds the buoyancy of the gas, the droplet detaches from the outermost drainage layer, and the gas is discharged through the outer surface of the coalescing layer. The demisting structure is mainly used to capture droplets entrained in the gas flow, effectively improving separation efficiency, improving downstream operation conditions, and reducing environmental pollution. The train loading exhaust gas absorption device of the present invention can make the liquid droplet content of the outlet gas less than 50mg / m3.

[0048] The diesel absorption tower 7 includes a diesel absorption tower shell 701, a first diesel inlet 702, a second swirl jet absorber 703, a second flow distribution module 704, a second gas inlet 705, a purified gas outlet 706, a second corrugated baffle module 707, a second fiber condensation module 708, a second partition plate 709, a second downcomer 710, and a second drain outlet 711. The diesel absorption tower shell is arranged from top to bottom with the second corrugated baffle module 707, the second fiber condensation module 708, the second swirl jet absorber 703, the second flow distribution module 704, the second partition plate 709 for fixing the modules, and the second downcomer 710 connected to the partition plate. The first diesel inlet 702 is located on one side of the shell. The upper end of the diesel absorption tower shell has a purified gas outlet 706, and the lower end of the diesel absorption tower shell has a second drain outlet 711. The second gas inlet 705 is located in the lower middle part of one side of the diesel absorption tower shell and corresponds to the second flow distribution module 704. The purified gas outlet 706 is cylindrical and connected to the RTO unit 9 via a pipeline. A second downcomer 710 is installed inside the casing, allowing droplets to gradually accumulate within the module and then flow into the liquid accumulation area at the bottom of the casing via the second downcomer 710. The oil-gas dehydrator 5 and diesel absorption tower 7 achieve highly efficient purification and removal of train loading exhaust gas. The process is simple, and the inclusion of a flow-guiding and liquid-removing module significantly suppresses and eliminates mist entrainment issues.

[0049] The second swirl-jet absorber 703 includes a swirl-jet absorber housing 7031, a first gas inlet 7032, a jacket 7033, an overflow pipe 7034, and a swirl-jet drain port 7035. The jacket is fitted outside the swirl-jet absorber housing, and a cavity structure capable of accommodating diesel fuel is formed between the inner surface of the jacket and the outer surface of the cylinder. The overflow pipe is located in the upper part of the inner cavity of the swirl-jet absorber housing, and a swirl-jet drain port is provided at the lower end of the swirl-jet absorber housing. Injection holes are provided on the outer circumferential surface of the swirl-jet absorber housing 7031 to allow diesel fuel to be injected into the cylinder. The injection holes allow diesel fuel to be injected into the swirl-jet absorber housing 7031 of the second swirl-jet absorber 703 and form a jet flow field. In specific embodiments, there are multiple second swirl-jet absorbers 703, and each swirl-jet absorber can be used in multi-stage series. Users can select any number according to their needs.

[0050] The diesel dehydrator 8 includes a diesel dehydrator housing 801, a second diesel inlet 802, a coarse fiber module 803, a third corrugated baffle module 804, a third fiber coagulation module 805, a diesel outlet 806, a fixed module assembly 807, and a third drain port 808. The coarse fiber module 803, the third corrugated baffle module 804, and the third fiber coagulation module 805 are arranged sequentially from left to right within the inner cavity of the diesel dehydrator housing 801. The third corrugated baffle module 804 and the third fiber coagulation module 805 are respectively connected to the inner wall of the diesel dehydrator housing 801 via the fixed module assembly 807. The diesel inlet is located at the left end of the diesel dehydrator housing, and a diesel outlet is located on the upper side of one side of the diesel dehydrator housing, while the third drain port 808 is located on the lower side.

[0051] The oil conveying device includes a heat exchanger 2 and a refrigerant 3. The heat exchanger is connected to the refrigeration unit through a pipeline. The output end of the refrigeration unit is connected to the diesel absorption tower 7 through a pipeline. The diesel fuel is fed into the diesel absorption tower 7 after heat exchange in the heat exchanger 2 and cooling by the refrigerant 3.

[0052] A method for absorbing exhaust gas from a train loading device includes the following steps:

[0053] S01, Oil and gas dehydration: The exhaust gas 1 from the train loading is input into the oil and gas dehydrator 5 and initially dehydrated by the flow distribution module 503. After the gas rises and is blocked by the partition plate, it enters the first swirl jet absorber 502 for secondary dehydration. After passing through the overflow pipe of the first swirl jet absorber 502, the gas is initially separated by the impact of the top buffer cap. After that, the rising gas enters the first corrugated baffle module 506 and the first fiber coagulation module 507 for deep separation. The droplets gradually accumulate in the modules and flow into the liquid accumulation area at the bottom of the oil and gas dehydrator shell 501 through the downcomer and are discharged from the equipment. The dehydrated gas enters the diesel absorption tower 7.

[0054] S02, Diesel Absorption: The gas to be treated after dehydration by the oil-gas dehydrator 5 is input into the diesel absorption tower 7 and undergoes preliminary dehydration via the flow distribution module 704. Simultaneously, diesel enters the diesel absorption tower 7 and is transported through the distribution pipe to the jacket 7033 of the second rotary jet absorber 703. The gas rises and is blocked by the partition plate before entering the second rotary jet absorber 703 to fully mix with the diesel and undergo three-stage micro-interface oscillation absorption. The droplets fall along the liquid leg of the second rotary jet absorber 703 into the liquid accumulation area at the bottom of the diesel absorption tower shell 701. After passing through the overflow pipe 7034 of the second rotary jet absorber 703, the gas undergoes preliminary separation by impact from the top buffer cap. Subsequently, the rising gas enters the second corrugated baffle module 707 and the second fiber coagulation module 708 for deep separation. The droplets gradually accumulate in the modules and flow through the second downcomer 710 into the liquid accumulation area at the bottom of the diesel absorption tower shell 701 for discharge.

[0055] S03, Reuse and Discharge: The purified gas discharged from the diesel absorption tower 7 is sent to the RTO unit 9 for further treatment. The diesel collected at the bottom of the diesel absorption tower shell 701 is transported to the diesel dehydrator 8 for dehydration via the oil discharge device. The liquid flows into the discharge device at the bottom of the diesel dehydrator shell 801. The dehydrated diesel is then sent to the subsequent unit for dehydrogenation treatment.

[0056] Further, in step S02 above, the second rotary spray absorber 703 atomizes the diesel fuel into small droplets, and the gas and diesel fuel are thoroughly mixed to perform three-stage micro-interface oscillation absorption. It can be understood that "micro-interface oscillation absorption" generates an interfacial effect, which refers to the physical and chemical phenomena that occur between two contacting substances due to the influence of surface energy. The micro-interface enhanced reactor increases the contact area between the reactants and the catalyst through a fine interface, thereby improving the reaction rate and efficiency. This improves the reaction rate and efficiency of diesel fuel and exhaust gas in the absorption device.

[0057] In a specific embodiment of the present invention, the train loading exhaust gas 1 and diesel fuel, after preliminary liquid removal, enter the second swirl jet absorber 703. Due to the interaction and interference between the rotating turbulent flow field generated by the gas phase and the jet flow field generated by the liquid phase, the absorbent in the liquid phase is cut and atomized by the rotating turbulent flow field to form droplets with smaller diameters. The droplets contact the train loading exhaust gas 1 to form a micro-interface reaction zone. As the reaction proceeds, this zone is continuously generated, evolved, and disappears, and the various VOCs exhaust gases are fully absorbed. The diesel fuel that has absorbed the VOCs exhaust gases flows out of the diesel absorption tower under the action of gravity and enters the diesel dehydrator 8 for further treatment.

[0058] Furthermore, in step S02 above, the gas to be treated enters the second swirl absorber 703 after being blocked by the partition plate as it ascends from the second flow distribution module 704.

[0059] Furthermore, when absorbing the exhaust gas from train loading, the operating pressure drop within the absorption device needs to be controlled to less than 3 kPa. This is to avoid incomplete reaction affecting the purification effect. Here, "pressure drop" can be understood as the pressure reduction caused by energy loss when the fluid flows in the reaction vessel. In this invention, it refers to the pressure reduction caused by energy loss when the exhaust gas 1 from the train loading and diesel flow in the second rotary injector 703.

[0060] Operating parameters: Inlet gas flow rate 3000 m³ / h, operating temperature 40℃, design temperature 60℃, operating pressure 0.2 MPa, design pressure 0.38 MPa, inlet VOCs concentration approximately 615.49 g / m³. After treatment by the diesel fuel washing device for train loading exhaust gas of this invention, the VOCs content in the purified outlet gas is less than 15 g / m³, the liquid carryover in the outlet gas is less than 50 mg / m³, the pressure drop of the diesel fuel washing device for train loading exhaust gas of this invention is less than 3 kPa, and the service life of internal components is not less than 8 years, thus extending the service life of the equipment.

[0061] The above description is merely an illustration of some principles of the present invention. This specification is not intended to limit the present invention to the specific structures and applicable scope shown. Therefore, all possible modifications and equivalents that may be used fall within the scope of the patent application of this invention.

[0062] Apart from the technical features described in the specification, all other technical features are known to those skilled in the art.

Claims

1. An absorption device for exhaust gases from train loading, characterized in that, The system includes an air supply device, an oil supply device, an oil-gas dehydrator (5), a diesel absorption tower (7), a diesel dehydrator (8), a first decontamination oil tank (6), an oil discharge device, and a second decontamination oil tank (10). The air supply device is connected to the oil-gas dehydrator (5) for dehydrating the exhaust gas (1) from the train loading. The outlet of the oil-gas dehydrator is connected to the first decontamination oil tank (6) for treating the decontaminated liquid. The exhaust port of the oil-gas dehydrator is connected to the diesel absorption tower (7) for purifying and absorbing the exhaust gas (1) from the train loading. The inlet of the diesel absorption tower (7) is connected to the oil supply device for transporting diesel fuel. The exhaust port of the diesel absorption tower (7) is connected to the RTO device (9) for further processing the purified gas. The outlet of the diesel absorption tower (7) is connected to the diesel dehydrator (8) through a pipeline. The outlet of the diesel dehydrator is connected to the second decontamination oil tank (10) through a pipeline. The diesel absorption tower (7) includes a diesel absorption tower shell (701), a first diesel inlet (702), a second swirl jet absorber (703), a flow distribution module (704), a second gas inlet (705), a purified gas outlet (706), a second corrugated baffle module (707), a second fiber condenser module (708), a second partition plate (709), a second downcomer (710), and a second drain outlet (711). The diesel absorption tower shell is equipped with the second corrugated baffle module (707) and the second fiber condenser module (708) from top to bottom. The module (708), the second swirl jet absorber (703), the second flow distribution module (704), the second partition plate (709) for fixing the module, and the second downcomer (710) connected to the partition plate are provided. The first diesel inlet (702) is located on one side of the shell. The upper end of the diesel absorption tower shell is provided with a purified gas outlet (706). The lower end of the diesel absorption tower shell is provided with a second drain outlet (711). The second gas to be treated inlet (705) is located in the lower middle part of one side of the diesel absorption tower shell and corresponds to the second flow distribution module (704).

2. The absorption device for train loading exhaust gas according to claim 1, characterized in that, The gas delivery device includes heat exchanger 2 (4), and the exhaust gas is fed into the oil-gas dehydrator after heat exchange in heat exchanger 2.

3. The absorption device for train loading exhaust gas according to claim 1, characterized in that, The oil-gas dehydrator (5) includes an oil-gas dehydrator shell (501), a first rotary jet absorber (502), a flow distribution module (503), a train loading exhaust gas inlet (504), an exhaust port (505), a demisting module, a first partition plate (508), a first downcomer (509), and a first drain port (510). The first downcomer (509) is located inside the shell, and the demisting module is located in the upper part of the inner cavity of the oil-gas dehydrator shell. The lower part is provided with a first partition plate (508). A flow distribution module (503) is provided above the partition plate in the lower part of the inner cavity of the oil-gas dehydrator. A first swirl jet absorber (502) is provided above the flow distribution module. The first drain port (510) is located at the lower end of the oil-gas dehydrator. The exhaust port (505) is located at the upper end of the oil-gas dehydrator. The train loading exhaust gas inlet (504) is located on one side of the oil-gas dehydrator and corresponds to the flow distribution module.

4. The absorption device for train loading exhaust gas according to claim 3, characterized in that, The defogging module includes a first corrugated baffle module (506) and a first fiber condensation module (507), which are respectively connected to the inner wall of the housing (501) through a fixed module assembly.

5. The absorption device for train loading exhaust gas according to claim 1, characterized in that, The second rotary jet absorber (703) includes a rotary jet absorber housing (7031), a first gas inlet (7032), a jacket (7033), an overflow pipe (7034), and a rotary jet drain port (7035). The jacket is fitted outside the rotary jet absorber housing, and a cavity structure capable of accommodating diesel fuel is formed between the inner surface of the jacket and the outer surface of the cylinder. The overflow pipe is located in the upper part of the inner cavity of the rotary jet absorber housing, and a rotary jet drain port is provided at the lower end of the rotary jet absorber housing.

6. The absorption device for train loading exhaust gas according to claim 1, characterized in that, The diesel dehydrator includes a diesel dehydrator shell (801), a second diesel inlet (802), a coarse fiber module (803), a third corrugated baffle module (804), a third fiber coagulation module (805), a diesel outlet (806), a fixed module assembly (807), and a third drain port (808). The coarse fiber module (803), the third corrugated baffle module (804), and the third fiber coagulation module (805) are arranged sequentially from left to right in the inner cavity of the diesel dehydrator shell (801). The third corrugated baffle module (804) and the third fiber coagulation module (805) are respectively connected to the inner wall of the diesel dehydrator shell (801) through the fixed module assembly (807). The diesel inlet is located at the left end of the diesel dehydrator shell. The diesel outlet is located on the upper side of one side of the diesel dehydrator shell, and the third drain port (808) is located on the lower side.

7. The absorption device for train loading exhaust gas according to claim 1, characterized in that, The oil conveying device includes a heat exchanger (2) and a refrigeration unit (3). The heat exchanger and the refrigeration unit are connected by a pipeline. The output end of the refrigeration unit is connected to the diesel absorption tower (7) by a pipeline. The diesel fuel is fed into the diesel absorption tower (7) after heat exchange by the heat exchanger (2) and cooling by the refrigeration unit (3).

8. The absorption method of the train loading exhaust gas absorption device according to any one of claims 1 to 7, characterized in that, Includes the following steps: S01, Oil and gas dehydration: The exhaust gas (1) of the train loading is input into the oil and gas dehydrator (5) and initially dehydrated by the flow distribution module (503). The gas rises and is blocked by the partition plate and enters the first swirl jet absorber (502) for secondary dehydration. The gas passes through the overflow pipe of the first swirl jet absorber (502) and is initially separated by the impact of the top buffer cap. After that, the gas rises and enters the first corrugated baffle module (506) and the first fiber coagulation module (507) for deep separation. The droplets gradually accumulate in the module and flow into the liquid accumulation area at the bottom of the shell (501) through the downcomer and are discharged from the equipment. The dehydrated gas enters the diesel absorption tower (7). S02, Diesel Absorption: The gas to be treated after being dehydrated by the oil-gas dehydrator (5) is input into the diesel absorption tower (7) and then undergoes preliminary dehydration through the second flow distribution module (704). At the same time, diesel enters the diesel absorption tower (7) and is transported to the jacket (7033) of the second rotary jet absorber (703) through the distribution pipe. After the gas rises and is blocked by the partition plate, it enters the second rotary jet absorber (703) and mixes thoroughly with the diesel for three-stage micro-interface oscillation absorption. The droplets fall along the liquid leg of the second rotary jet absorber (703) into the bottom liquid accumulation area of ​​the diesel absorption tower shell (701). After the gas passes through the overflow pipe (7034) of the second rotary jet absorber (703), it is initially separated by the impact of the top buffer cap. After that, the rising gas enters the second corrugated baffle module (707) and the second fiber coagulation module (708) for deep separation. The droplets gradually accumulate in the module and flow into the bottom liquid accumulation area of ​​the diesel absorption tower shell (701) through the second downcomer (710) and are discharged from the equipment. S03, Reuse and Discharge: The purified gas discharged from the diesel absorption tower (7) is sent to the RTO device (9) for further processing. The diesel collected at the bottom of the diesel absorption tower shell (701) is transported to the diesel dehydrator (8) for dehydration via the oil discharge device. The liquid flows into the discharge device at the bottom of the diesel dehydrator shell (801). The dehydrated diesel is sent to the subsequent device for dehydrogenation treatment.

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