Space launch hydrazine fuel waste gas purification treatment device and method

Abstract

The invention relates to the technical field of fuel waste gas, in particular to an aerospace launch hydrazine fuel waste gas purification treatment device and method.The aerospace launch hydrazine fuel waste gas purification treatment device comprises a plurality of tubular reactors connected in series, the inner walls of the tubular reactors are coated with titanium-based catalyst coatings, the upper portions in the tubular reactors are oxidation reaction chambers, and the lower portions in the tubular reactors are ozone treatment chambers; an ozone aeration disc is mounted at the bottom in the ozone treatment chamber, an ozone inlet is formed in one side of the ozone aeration disc, the ozone inlet is formed in the side wall of the ozone treatment chamber, and a granular porous adsorption material is laid on the top surface of the ozone aeration disc; an ultraviolet lamp tube is arranged between the top in the tubular reactor and the top surface of the granular porous adsorption material, and the ultraviolet lamp tube is mounted at the top in the oxidation reaction chamber; the bottom of the tubular reactor is communicated with a drainage pipe. The device is not only suitable for treating waste gas generated in the hydrazine fuel transfer and filling process, but also suitable for hydrazine fuel production and transportation and purification treatment of hydrazine fuel waste gas in other places.

Description

Technical Field

[0001] This invention relates to the field of fuel exhaust technology, and in particular to a device and method for purifying and treating hydrazine-based fuel exhaust gases from aerospace launches. Background Technology

[0002] Hydrazine-based fuels are commonly used conventional liquid propellants in space launches. Their main characteristics are flammability, high toxicity, and environmental hazards. They are easily volatilized and adsorbed at room temperature; inhalation and ingestion can lead to poisoning in humans, and long-term exposure to low concentrations can also cause chronic poisoning. Once released into the atmosphere, they can cause poisoning of aquatic organisms and have adverse effects on aquatic environments.

[0003] Hydrazine fuels emit exhaust gases and cause air pollution during their use at launch sites, including during transfer, loading, storage, and analysis. Due to the limitations of these use scenarios, exhaust gas collection and treatment has always been a challenge for launch site exhaust gas management.

[0004] In addition to its use in space launches, hydrazine fuels are widely used in the aerospace system and various branches of the armed forces. Fuel exhaust treatment is a fundamental guarantee for ensuring the physical and mental health of test participants, protecting the atmospheric environment, and ensuring the successful completion of national defense tests.

[0005] The main treatment methods for hydrazine fuel exhaust gas are combustion (CN1786573A, CN1304014A), catalytic oxidation (CN105561775A), photocatalytic degradation (CN112844040A), and spray absorption (CN1100448999A).

[0006] Combustion methods require a high concentration of hydrazine in the exhaust gas; otherwise, a large amount of combustion-supporting materials will be consumed during combustion. Therefore, this method is unsuitable for treating low-concentration hydrazine exhaust gases during aerospace launches. Catalytic oxidation uses a perovskite-type composite oxidant as a catalyst, utilizing oxygen in the air at 400-600℃ to oxidize and decompose hydrazine fuel into carbon dioxide, water, and nitrogen oxides for emission. Photocatalytic degradation uses a titanium-based compound as a catalyst, undergoing an oxidation reaction under sunlight. Both of these methods involve chemical reactions under the action of self-developed catalysts. Due to limited application scenarios, they are easily affected by catalyst manufacturing conditions and reaction conditions, leading to poor treatment effects and failing to meet the requirements for continuous harmless emission. Spray absorption generally uses multiple solution absorption reaction tanks connected in series. The exhaust gas reacts with the spray solution inside the pipes, ultimately discharging wastewater. This method's final effluent contains reaction intermediates and hydrazine substances, requiring harmless wastewater treatment before discharge. Furthermore, multiple tanks connected in series result in a large footprint and numerous limitations in practical application.

[0007] Numerous patents and reports exist regarding the treatment of wastewater and liquids with similar compositions to hydrazine fuel exhaust gases. Among these, the advanced oxidation method combining ozone and ultraviolet light is the earliest researched, technologically mature, and highly efficient method that has been consistently used. In the ozone and ultraviolet light combined reaction system, the reaction rate of hydrazine fuel-containing wastewater is 100-1000 times higher than that using ozone alone. Furthermore, the hydrazine is decomposed thoroughly, with no nitrosodimethylamine produced, and the formaldehyde concentration meets the emission requirement of less than 0.2 mg / L. While the advanced oxidation method combining ozone and ultraviolet light is widely used in organic waste gas treatment, its application to hydrazine fuel exhaust gas treatment has not yet been reported.

[0008] Therefore, there is an urgent need for a device and method for purifying and treating exhaust gases from hydrazine fuels used in space launches. This method would utilize an advanced oxidation process combining ozone and ultraviolet light to purify exhaust gases generated during the transfer and loading of hydrazine fuels at space launch sites, as well as exhaust gases from hydrazine fuel production, transportation, and other usage locations. Summary of the Invention

[0009] The purpose of this invention is to provide a device and method for purifying and treating exhaust gas from hydrazine fuels used in aerospace launches, in order to solve the problems existing in the prior art.

[0010] To achieve the above objectives, the present invention provides the following solution: a purification and treatment device for hydrazine fuel exhaust gas from aerospace launches, comprising multiple tubular reactors connected in series. The inner wall of each tubular reactor is coated with a titanium-based catalyst coating. The upper part of each tubular reactor is an oxidation reaction chamber, and the lower part is an ozone treatment chamber. An ozone aeration disc is installed at the bottom of the ozone treatment chamber, and an ozone inlet is provided on one side of the ozone aeration disc. The ozone inlet is located on the side wall of the ozone treatment chamber. The top surface of the ozone aeration disc is covered with granular porous adsorbent material. An ultraviolet lamp is installed between the top of the tubular reactor and the top surface of the granular porous adsorbent material, and the ultraviolet lamp is installed at the top of the oxidation reaction chamber. A drain pipe is connected to the bottom of the tubular reactor.

[0011] Preferably, the ultraviolet lamp is fitted with a quartz tube, which is installed at the top inside the tubular reactor.

[0012] Preferably, the number of the plurality of tubular reactors is odd.

[0013] Preferably, the plurality of tubular reactors are divided into a first branch tubular reactor, a plurality of second branch tubular reactors, a plurality of third branch tubular reactors and a last branch tubular reactor.

[0014] Preferably, the upper part of the outer wall of the first branch tube reactor, the second branch tube reactor, the third branch tube reactor, and the last branch tube reactor are all provided with air outlets.

[0015] Preferably, the outlet of the last tubular reactor is an exhaust port.

[0016] Preferably, air inlets are provided on the lower middle part of the outer wall of the first branch tube reactor, the second branch tube reactor, the third branch tube reactor, and the last branch tube reactor.

[0017] Preferably, the air inlet is located on the inner wall of the tubular reactor above the top surface of the granular porous adsorbent material.

[0018] Preferably, the total number of the plurality of second branch reactors and the plurality of third branch reactors is an odd number; each of the third branch reactors is disposed between two adjacent second branch reactors.

[0019] A method for purifying and treating exhaust gas from hydrazine fuel used in space launches includes the following steps: Ozone decomposes under the ultraviolet light of the ultraviolet lamp to produce oxygen and ground-state oxygen atoms, and is excited to produce more hydroxyl radicals with the participation of water molecules, forming a system in the oxidation reaction chamber where ultraviolet light and a variety of highly reactive oxides coexist. Hydrazine fuels are oxidized into azo compounds in the presence of multiple highly reactive oxides, and further decomposed into nitrogen oxides, carbon dioxide and water under further oxidation. The oxidation intermediates fall into the ozone treatment chamber with the water and are absorbed by the granular porous adsorption material. They are then oxidized and decomposed by ozone, eventually decomposing into carbon dioxide and water.

[0020] The present invention discloses the following technical effects: This invention utilizes the confined space within the tubular reactor to increase the contact probability between ultraviolet light, ozone, hydrazine fuel exhaust gas, and the catalyst. The connection of multiple tubular reactors in series extends the reaction time, resulting in faster oxidation and ensuring the complete decomposition of intermediate products. Simultaneously, the intermediate products generated during the reaction are adsorbed by the granular porous adsorption material at the bottom, which not only prevents incomplete decomposition of intermediate products from being discharged from the system but also creates conditions for subsequent long-term contact decomposition. Furthermore, the combination of multiple tubular reactors in series facilitates equipment standardization and automation.

[0021] This invention connects multiple tubular reactors in series, making it suitable not only for treating waste gas generated during the transfer and loading of hydrazine fuel at space launch sites, but also for purifying waste gas from hydrazine fuel production, transportation, and other usage sites. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a top view of the structure of the present invention; Figure 2 This is a schematic diagram of the structure of multiple tubular reactors connected in sequence according to the present invention; Figure 3 This is a schematic diagram of the structure of the first branch tube reactor of the present invention; Figure 4 This is a schematic diagram of the second branch tube reactor structure of the present invention; Figure 5 This is a schematic diagram of the third branch tube reactor structure of the present invention; Figure 6 This is a schematic diagram of the last branch tubular reactor structure of the present invention; The components include: 1. Air outlet; 2. Oxidation reaction chamber; 3. Titanium-based catalyst coating; 4. Particulate porous adsorbent material; 5. Ozone aeration disc; 6. Drain pipe; 7. Quartz tube; 8. Ultraviolet lamp tube; 9. Air inlet; 10. Ozone inlet; 11. Exhaust port; and 12. Tubular reactor. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] Reference Figures 1 to 6This invention provides a device for purifying and treating exhaust gas from hydrazine fuel used in aerospace launches, comprising multiple tubular reactors 12 connected in series. The inner wall of each tubular reactor 12 is coated with a titanium-based catalyst coating 3. The upper part of each tubular reactor 12 is an oxidation reaction chamber 2, and the lower part is an ozone treatment chamber. An ozone aeration disc 5 is installed at the bottom of the ozone treatment chamber, and an ozone inlet 10 is provided on one side of the ozone aeration disc 5. The ozone inlet 10 is located on the side wall of the ozone treatment chamber. The top surface of the ozone aeration disc 5 is covered with granular porous adsorbent material 4. An ultraviolet lamp 8 is installed between the top of the tubular reactor 12 and the top surface of the granular porous adsorbent material 4. The ultraviolet lamp 8 is installed at the top of the oxidation reaction chamber 2. A drain pipe 6 is connected to the bottom of the tubular reactor 12.

[0027] This invention utilizes the confined space within the tubular reactor 12 to increase the contact probability between ultraviolet light, ozone, hydrazine fuel exhaust gas, and the catalyst. The connection of multiple tubular reactors 12 in series extends the reaction time, resulting in faster oxidation and ensuring the complete decomposition of intermediate products. Simultaneously, the intermediate products generated during the reaction are adsorbed by the granular porous adsorption material 4 at the bottom, which not only prevents incomplete decomposition of intermediate products from being discharged from the system but also creates conditions for subsequent long-term contact decomposition. Furthermore, the combination of multiple tubular reactors 12 in series facilitates equipment standardization and automation.

[0028] This invention connects multiple tubular reactors 12 in series, making it suitable not only for treating waste gas generated during the transfer and loading of hydrazine fuel at space launch sites, but also for purifying waste gas from hydrazine fuel production, transportation, and other usage sites.

[0029] Further optimization involves an outer casing of the UV lamp 8 with a quartz tube 7, which is installed at the top inside the tubular reactor 12. The quartz tube 7 plays a crucial role as the outer casing, its core advantage being its high light transmittance, effectively allowing ultraviolet light (especially the UVC band) to pass through, while providing high-temperature resistance, corrosion resistance, and mechanical protection, extending the lifespan of the UV lamp 8 and ensuring safety and efficiency in applications such as water treatment and air purification.

[0030] The ultraviolet lamp 8 inside the quartz tube 7 can emit ultraviolet light with a wavelength of no more than 387.5nm during the reaction process.

[0031] Further optimization involves using an odd number of tubular reactors 12. Multiple tubular reaction units are connected in series to form a disk shape, which not only reduces the equipment's footprint but also facilitates the connection of multiple tubular reactors 12.

[0032] Multiple tubular reactors 12 can be connected in series, or arranged in a row or other forms.

[0033] Each tubular reactor 12 can be 50mm-80mm in diameter and 1.5m-2m in length.

[0034] The scheme was further optimized so that the multiple tubular reactors were divided into a first branch tubular reactor, multiple second branch tubular reactors, several third branch tubular reactors, and a last branch tubular reactor.

[0035] The hydrazine fuel exhaust gas enters from the first branch tubular reactor, passes through multiple second branch tubular reactors and several third branch tubular reactors, and is discharged from the last branch tubular reactor; this effectively extends the reaction time.

[0036] To further optimize the design, an air outlet 1 is provided on the upper part of the outer wall of the first branch tubular reactor, the second branch tubular reactor, the third branch tubular reactor, and the last branch tubular reactor.

[0037] The first branch tube reactor, the second branch tube reactor, and the third branch tube reactor can be connected to each other in sequence through the air outlet 1.

[0038] That is, the outlet 1 of the first branch tube reactor is connected to the outlet 1 of the second branch tube reactor, the outlet 1 of the second branch tube reactor is connected to the outlet 1 of the third branch tube reactor, and the outlet 1 of the third branch tube reactor is connected to the outlet 1 of another second branch tube reactor.

[0039] Further optimization of the scheme resulted in the last branch tube reactor's outlet 1 being the exhaust outlet 11.

[0040] By setting an odd number of multiple tubular reactors 12, the exhaust port 11 of the last tubular reactor is located at the top.

[0041] To further optimize the design, air inlets 9 are provided on the lower middle part of the outer wall of the first, second, third, and last tubular reactors.

[0042] The second, third, and last tubular reactors can be sequentially connected to each other through the air inlet 9.

[0043] That is, the air inlet 9 of the second branch tubular reactor is connected to the air inlet 9 of the third branch tubular reactor, the air inlet 9 of the third branch tubular reactor is connected to the air inlet 9 of another second branch tubular reactor, and the air inlet 9 of the second branch tubular reactor adjacent to the last branch tubular reactor is connected to the air inlet 9 of the last branch tubular reactor.

[0044] To further optimize the design, the air inlet 9 is located on the inner wall of the tubular reactor 12, above the top surface of the granular porous adsorbent material 4. This allows the hydrazine fuel exhaust gas to effectively enter the oxidation reaction chamber 2.

[0045] In a further optimized scheme, the total number of multiple second branch tubular reactors and several third branch tubular reactors is an odd number; each third branch tubular reactor is respectively set between two adjacent second branch tubular reactors.

[0046] When five tubular reactors 12 are used, they include one first branch tubular reactor, two second branch tubular reactors, one third branch tubular reactor, and one last branch tubular reactor.

[0047] When seven tubular reactors 12 are used, they include one first branch tubular reactor, three second branch tubular reactors, two third branch tubular reactors, and one last branch tubular reactor.

[0048] The total number of multiple second-branch reactors and several third-branch reactors is odd, so that the total number of one first-branch reactor, multiple second-branch reactors, several third-branch reactors, and one last-branch reactor can be odd.

[0049] A method for purifying and treating exhaust gas from hydrazine fuel used in space launches includes the following steps: Ozone decomposes under the ultraviolet light of the ultraviolet lamp 8 to produce oxygen and ground-state oxygen atoms, and is excited to produce more hydroxyl radicals with the participation of water molecules, forming a system in which ultraviolet light and a variety of highly reactive oxides coexist in the oxidation reaction chamber 2; that is, under the ultraviolet light of the ultraviolet lamp 8, the titanium-based catalyst coating 3 can catalyze ozone and ultraviolet light to generate hydroxyl radicals with strong oxidizing power.

[0050] Hydrazine fuels are oxidized into azo compounds in a system where multiple highly reactive oxides coexist, and further decomposed into nitrogen oxides, carbon dioxide, and water under continued oxidation; the water is discharged through drain pipe 6.

[0051] The oxidation intermediates fall into the ozone treatment chamber with the water and are absorbed by the granular porous adsorbent material 4. They are then oxidized and decomposed by ozone, ultimately breaking down into carbon dioxide and water. In other words, the granular porous adsorbent material 4 is used to absorb the high-boiling-point intermediates generated during the reaction process and oxidize and decompose them.

[0052] This invention constructs a mixed reaction system of ozone, ultraviolet light, and hydrazine fuel exhaust gas under catalytic conditions within each tubular reactor 12. The titanium-based catalyst coating 3 is utilized to stimulate ozone to generate a large number of hydroxyl radicals with strong oxidizing power, oxidizing and decomposing hydrazine fuel into small molecules such as carbon dioxide. Then, the non-gaseous substances generated during the hydrazine fuel exhaust gas oxidation reaction are adsorbed by the particulate porous adsorbent material 4, oxidized and decomposed by ozone, and volatilized into gaseous substances before entering the oxidation reaction chamber 2 for further oxidation and decomposition into carbon dioxide and other substances for discharge.

[0053] This invention utilizes a tubular reaction method and apparatus for the oxidative decomposition of hydrazine fuel exhaust gas using ozone, ultraviolet light, and a catalyst. This method achieves effective decomposition and purification of the exhaust gas while avoiding the generation of secondary pollutants.

[0054] This invention is applicable not only to the treatment of exhaust gases from hydrazine fuel refueling and transfer at space launch sites, but also to the needs of exhaust gas treatment at sites where other hydrazine fuels and substances with similar properties are produced, transported, stored, tested, or used.

[0055] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0056] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A device for purifying and treating exhaust gas from hydrazine fuel used in aerospace launches, characterized in that: It includes multiple tubular reactors (12) connected in series, the inner wall of the tubular reactor (12) is coated with a titanium-based catalyst coating (3), the upper part of the tubular reactor (12) is an oxidation reaction chamber (2), and the lower part of the tubular reactor (12) is an ozone treatment chamber. An ozone aeration disc (5) is installed at the bottom of the ozone treatment chamber. An ozone inlet (10) is provided on one side of the ozone aeration disc (5). The ozone inlet (10) is located on the side wall of the ozone treatment chamber. A granular porous adsorption material (4) is laid on the top surface of the ozone aeration disc (5). An ultraviolet lamp (8) is provided between the top of the tubular reactor (12) and the top surface of the granular porous adsorbent material (4), and the ultraviolet lamp (8) is installed at the top of the oxidation reaction chamber (2). The bottom of the tubular reactor (12) is connected to a drain pipe (6).

2. The aerospace launch hydrazine fuel exhaust gas purification and treatment device according to claim 1, characterized in that: The ultraviolet lamp (8) is covered with a quartz tube (7), which is installed at the top inside the tubular reactor (12).

3. The aerospace launch hydrazine fuel exhaust gas purification and treatment device according to claim 1, characterized in that: The number of the multiple tubular reactors (12) is odd.

4. The aerospace launch hydrazine fuel exhaust gas purification and treatment device according to claim 3, characterized in that: The multiple tubular reactors (12) are divided into a first branch tubular reactor, multiple second branch tubular reactors, several third branch tubular reactors and a last branch tubular reactor.

5. The aerospace launch hydrazine fuel exhaust gas purification and treatment device according to claim 4, characterized in that: The upper part of the outer wall of the first branch tube reactor, the second branch tube reactor, the third branch tube reactor and the last branch tube reactor are all provided with air outlets (1).

6. The aerospace launch hydrazine fuel exhaust gas purification and treatment device according to claim 5, characterized in that: The outlet (1) of the last branch tubular reactor is the exhaust port (11).

7. The aerospace launch hydrazine fuel exhaust gas purification and treatment device according to claim 4, characterized in that: Air inlets (9) are provided in the lower middle part of the outer wall of the first branch tube reactor, the second branch tube reactor, the third branch tube reactor and the last branch tube reactor.

8. The aerospace launch hydrazine fuel exhaust gas purification and treatment device according to claim 7, characterized in that: The air inlet (9) is located on the inner wall of the tubular reactor (12) above the top surface of the granular porous adsorbent material (4).

9. The aerospace launch hydrazine fuel exhaust gas purification and treatment device according to claim 4, characterized in that: The total number of the plurality of second branch tubular reactors and the plurality of third branch tubular reactors is an odd number; Each of the third branch reactors is disposed between two adjacent second branch reactors.

10. A method for purifying and treating exhaust gas from hydrazine fuel used in aerospace launches, based on the aerospace launch hydrazine fuel exhaust gas purification and treatment device according to any one of claims 1-9, characterized in that: Includes the following steps: Ozone decomposes under the ultraviolet light of the ultraviolet lamp (8) to produce oxygen and ground-state oxygen atoms, and is excited to produce more hydroxyl radicals with the participation of water molecules, forming a system in which ultraviolet light and a variety of highly reactive oxides coexist in the oxidation reaction chamber (2). Hydrazine fuels are oxidized into azo compounds in the presence of multiple highly reactive oxides, and further decomposed into nitrogen oxides, carbon dioxide and water under further oxidation. The oxidation intermediates fall into the ozone treatment chamber with the water and are absorbed by the granular porous adsorbent material (4). They are then oxidized and decomposed by ozone, eventually decomposing into carbon dioxide and water.

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