Ultraviolet catalytic decomposition device, tail gas treatment device and crosslinking tail gas treatment process

Abstract

The invention provides an ultraviolet catalytic decomposition device, a tail gas treatment device and a cross-linked tail gas treatment process, and particularly relates to the technical field of tail gas treatment. The ultraviolet light catalytic decomposition device comprises a shell and an ultraviolet light emitting device arranged in the shell, the ultraviolet light emitting device mainly comprises a low-pressure mercury lamp, a nitrogen pipe, a first quartz tube and a second quartz tube; each of the first quartz tube and the second quartz tube is of a structure of which one end is opened and the other end is closed; the first quartz tube is sleeved outside the low-pressure mercury lamp, the nitrogen tube is arranged in a gap between the first quartz tube and the low-pressure mercury lamp, and the second quartz tube is sleeved outside the first quartz tube. According to the ultraviolet light catalytic decomposition device disclosed by the invention, through the design of a double quartz tube structure and a built-in nitrogen tube, the photocatalytic efficiency is optimized, the operation safety is guaranteed, the service life of a light source is prolonged, the stability of ultraviolet light is ensured, and the stability of a reaction environment is maintained.

Description

Technical Field

[0001] The invention relates to the technical field of tail gas treatment, and in particular to an ultraviolet catalytic decomposition device, a tail gas treatment device and a treatment process for cross-linked tail gas. Background Art

[0002] In the production process of vitamin A microcapsules, cross-linking is a key step, which enhances the structural stability and protective properties of the microcapsules. The prior art usually uses a fluidized bed reactor to achieve this process. In this setting, a high-temperature and high-humidity airflow is introduced under the fluidizing plate, so that the vitamin A microcapsules above the fluidizing plate are maintained in a fluidized state. This fluidized environment provides uniform heat and humidity for the microcapsules, which is conducive to the cross-linking reaction.

[0003] Under high temperature and high humidity conditions, the gelatin component in the microcapsule, an animal-derived protein, undergoes the Maillard reaction with oligosaccharides, a non-enzymatic browning reaction that is widely present in food processing. This reaction leads to the formation of a network structure between protein molecules, thereby increasing the strength of the microcapsule and reducing its water solubility, which is crucial to improving the stability of the microcapsule and protecting the internal vitamin A component.

[0004] However, the Maillard reaction produces some byproducts, including small molecular organic matter, which are released into the air at high temperatures to form tail gas with a special odor. These tail gases not only cause odor problems in the production environment, but also may have potential impacts on the health of operators and the surrounding environment.

[0005] To solve this problem, the existing technology adopts a variety of tail gas treatment methods, including cyclone separation, washing and absorption processes. Although these methods reduce pollutants in the tail gas to a certain extent, they usually cannot completely eliminate the odor, resulting in unpleasant odors in the production area during the cross-linking process.

[0006] Cross-linked tail gas has three characteristics: high humidity, dust, and odor. The purpose of this application is to solve the odor problem. The high humidity characteristic makes it impossible to carry out the bag filter operation with the strongest dust removal ability, or it requires dehumidification before the bag filter operation can be used, which will sharply increase the processing cost. The dust characteristic will shorten the life of the ultraviolet lamp of the ultraviolet photocatalytic decomposition device, and the high humidity environment will further reduce the life of the ultraviolet lamp, thereby weakening the processing capacity of the entire system.

[0007] In view of this, the present invention is proposed. Summary of the invention

[0008] One of the purposes of the present invention is to provide an ultraviolet light catalytic decomposition device, aiming to solve at least one of the above-mentioned technical problems.

[0009] A second object of the present invention is to provide a tail gas treatment device.

[0010] The third object of the present invention is to provide a process for treating cross-linking tail gas.

[0011] In order to solve the above-mentioned technical problems, the present invention particularly adopts the following technical solutions:

[0012] A first aspect of the present invention provides an ultraviolet catalytic decomposition device including a housing and an ultraviolet light emitting device disposed in the housing;

[0013] The ultraviolet light emitting device is mainly composed of a low-pressure mercury lamp, a nitrogen tube, a first quartz tube and a second quartz tube;

[0014] The first quartz tube and the second quartz tube are both structures with one end open and the other end closed;

[0015] The first quartz tube is sleeved outside the low-pressure mercury lamp, the nitrogen tube is arranged in the gap between the first quartz tube and the low-pressure mercury lamp, and the second quartz tube is sleeved outside the first quartz tube.

[0016] Furthermore, the ratio of the inner diameter of the shell to the outer diameter of the second quartz tube is 3 to 10:1.

[0017] Furthermore, the shell is a cylindrical structure; the shell includes a cylinder body, an upper cylinder cover and a lower cylinder cover.

[0018] The cylinder is provided with an air inlet and an air outlet.

[0019] The central axis of the ultraviolet light emitting device coincides with the central axis of the cylinder.

[0020] The air inlet is arranged at the bottom of the cylinder and is tangent to the cylinder to form a centrifugal structure.

[0021] The air outlet is arranged at the top of the cylinder and is tangent to the cylinder, and the air outlet and the air inlet are arranged on different sides.

[0022] Furthermore, the air inlet and the air outlet are both square structures and are centrally symmetrical about the central axis of the cylinder.

[0023] Wherein, the ratio of the height to the width of the air inlet is 1.5 to 3:1.

[0024] The ratio of the width of the air inlet to the inner diameter of the cylinder is 0.10-0.25:1.

[0025] Furthermore, the upper cylinder cover is arranged on the top of the cylinder;

[0026] A mounting tube is provided at the center of the upper cylinder cover, and the mounting tube is used to mount and fix the ultraviolet light emitting device.

[0027] The lower cylinder cover is arranged at the bottom of the cylinder body.

[0028] A drain pipe is provided on the outer periphery of the lower cylinder cover; the drain pipe is used to discharge the liquid accumulated in the ultraviolet catalytic decomposition device.

[0029] The second aspect of the present invention provides a tail gas treatment device, comprising a cyclone separator, a cyclone water film dust collector and the ultraviolet catalytic decomposition device described in the first aspect, which are connected in sequence;

[0030] The air inlet of the ultraviolet catalytic decomposition device is connected to the output port of the cyclone water film dust collector;

[0031] The cyclone separator is used to perform a primary dust removal on the initial exhaust gas to obtain a primary exhaust gas; the cyclone water film dust collector is used to perform a secondary dust removal and organic gas absorption treatment on the primary exhaust gas to obtain a secondary exhaust gas; the ultraviolet light emitting device is used to perform ultraviolet light catalytic decomposition treatment on the secondary exhaust gas in the shell to obtain the final exhaust gas.

[0032] The third aspect of the present invention provides a process for treating cross-linked tail gas, which is treated by using the tail gas treatment device described in the second aspect;

[0033] The cross-linking tail gas is generated during the production of vitamin A microcapsules;

[0034] The treatment process comprises the following steps: the cross-linked tail gas is subjected to a primary dust removal through a cyclone separator to obtain a primary cross-linked tail gas; the primary cross-linked tail gas is further subjected to a secondary dust removal and a primary deodorization through a cyclone water film dust collector to obtain a secondary cross-linked tail gas; the secondary cross-linked tail gas is subjected to a secondary deodorization through an ultraviolet catalytic decomposition device to obtain an odorless cross-linked tail gas.

[0035] Furthermore, an absorbent is added into the cyclone water film dust collector.

[0036] Preferably, the absorbent comprises an aqueous solution of sodium hypochlorite.

[0037] Preferably, the concentration of the sodium hypochlorite aqueous solution is 1.0-5.0 wt %.

[0038] Furthermore, the ratio between the flow rate of the cross-linking tail gas and the power of the low-pressure mercury lamp is 2000-5000m 3 / h:1kW.

[0039] Furthermore, the temperature of the cross-linking tail gas is 85-100° C., and the absolute humidity is 0.04-0.055 kg / kg.

[0040] Compared with the prior art, the present invention has at least the following beneficial effects:

[0041] The ultraviolet catalytic decomposition device provided by the present invention has clear functions of each component to improve the photocatalytic efficiency and ensure the safety of operation. The low-pressure mercury lamp is sheathed by the first quartz tube to provide physical protection to prevent external factors such as dust and moisture from damaging the light source, thereby extending its service life. A nitrogen tube is provided in the gap between the first quartz tube and the low-pressure mercury lamp. By filling nitrogen to create an oxygen-free environment, it not only reduces the oxidation loss of the light source during operation, but also avoids the influence of oxidation on the wavelength of ultraviolet light, thereby ensuring the stability and catalytic effect of ultraviolet light. The second quartz tube is sheathed on the outside of the first quartz tube. This double quartz tube design not only enhances the durability and safety of the device, but also helps to maintain the stability of the internal reaction environment, which is crucial for the efficient conduct of ultraviolet catalytic reactions.

[0042] The tail gas treatment device provided by the present invention combines physical separation and chemical decomposition, adopts a multi-stage treatment mode, improves purification efficiency, avoids secondary pollution, and has a modular design for easy maintenance, thereby providing an efficient and environmentally friendly tail gas treatment method for industry.

[0043] The cross-linked tail gas treatment process provided by the present invention effectively removes dust and odor in the cross-linked tail gas generated in the production of vitamin A microcapsules in view of the beneficial effects brought by the tail gas treatment device. This process not only improves the cleanliness of the cross-linked tail gas, but also avoids secondary pollution, provides an efficient and environmentally friendly tail gas purification method for industrial production, and improves environmental quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1 A schematic diagram of the structure of an ultraviolet light emitting device provided by the present invention;

[0046] Figure 2 A schematic structural diagram of another ultraviolet light emitting device provided by the present invention;

[0047] Figure 3 A schematic diagram of the structure of the tail gas treatment device provided by the present invention;

[0048] Figure 4 A front view of the housing provided by the present invention;

[0049] Figure 5 A top view of the housing provided by the present invention;

[0050] Figure 6 A bottom view of the housing provided by the present invention.

[0051] Explanation of the main component symbols: 1-cyclone separator; 2-cyclone water film dust collector; 3-shell; 31-upper cylinder cover; 311-mounting pipe; 32-cylinder; 321-air inlet; 322-air outlet; 331-exhaust pipe; 33-lower cylinder cover; 4-ultraviolet light emitting device; 41-nitrogen pipe; 42-first quartz tube; 43-second quartz tube; 44-low-pressure mercury lamp; 45-cooling water inlet; 46-cooling water outlet. DETAILED DESCRIPTION

[0052] To make the purpose, technical solution and advantages of the present invention clearer, the technical solution in the embodiment of the present invention will be clearly and completely described below in combination with the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, but not all of the embodiments. The components of the embodiment of the present invention can be arranged and designed in various different configurations.

[0053] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0054] A first aspect of the present invention provides an ultraviolet catalytic decomposition device comprising a housing 3 and an ultraviolet light emitting device 4 disposed in the housing 3;

[0055] like Figure 1 As shown, the ultraviolet light emitting device 4 is mainly composed of a low-pressure mercury lamp 44, a nitrogen tube 41, a first quartz tube 42 and a second quartz tube 43;

[0056] The first quartz tube 42 and the second quartz tube 43 are both structures with one end open and the other end closed;

[0057] The first quartz tube 42 is sleeved on the outside of the low-pressure mercury lamp 44 , the nitrogen tube 41 is disposed in the gap between the first quartz tube 42 and the low-pressure mercury lamp 44 , and the second quartz tube 43 is sleeved on the outside of the first quartz tube 42 .

[0058] The ultraviolet photocatalytic decomposition device provided by the present invention has clear functions of each component to improve the photocatalytic efficiency and ensure the safety of operation. The low-pressure mercury lamp 44 is sheathed by the first quartz tube 42 to provide physical protection to prevent external factors such as dust and moisture from damaging the light source, thereby extending its service life.

[0059] In a preferred embodiment of the present invention, Figure 2 As shown, the outer surface of the first quartz tube 42 and the inner surface of the second quartz tube 43 constitute a heat exchange medium cavity. When the power of the ultraviolet lamp is very large, a cooling water inlet 45 and a cooling water outlet 46 can be set on the upper part of the ultraviolet light emitting device 4. Deionized water is preferably used as cooling water, so that deionized water enters the heat exchange medium cavity and takes away part of the heat emitted by the ultraviolet lamp. When the power of the ultraviolet lamp is very small, the nitrogen filled in the first quartz tube 42 is enough to take away the heat emitted by the ultraviolet lamp, and it is not necessary to add deionized water for heat exchange. At the same time, the second quartz tube 43 is provided to provide an additional protective layer for the device. Clean water can also be introduced from the outside to the outer wall of the second quartz tube 43 to facilitate cleaning of the outer wall of the quartz tube and extend the shutdown and maintenance cycle.

[0060] A nitrogen tube 41 is provided in the gap between the first quartz tube 42 and the low-pressure mercury lamp 44. By filling nitrogen to create an oxygen-free environment, it not only reduces the oxidation loss of the light source during operation, but also avoids the influence of oxidation on the wavelength of ultraviolet light, ensuring the stability and catalytic effect of ultraviolet light. The second quartz tube 43 is sleeved on the outside of the first quartz tube 42 to provide an additional protective layer for the device. This double quartz tube design not only enhances the durability and safety of the device, but also helps to maintain the stability of the internal reaction environment, which is crucial for the efficient conduct of ultraviolet light catalytic reactions.

[0061] Figure 3 , the relative structure of the ultraviolet light emitting device 4 and the housing 3 is shown, and the operating handle of the ultraviolet light emitting device 4 is located outside the housing 3.

[0062] The nitrogen tube 41 inserted into the first quartz tube 42 can cool the ultraviolet lamp when it is turned on, and also has the function of preventing the ultraviolet lamp connector from being oxidized. The second quartz tube 43 is provided to facilitate the removal of the entire ultraviolet light emitting device 4 and the cleaning of the outer wall of the second quartz tube 43, without the need to clean the first quartz tube 42, thereby avoiding possible damage to the ultraviolet lamp during the cleaning process.

[0063] Furthermore, the ratio of the inner diameter of the shell 3 to the outer diameter of the second quartz tube 43 is 3-10:1.

[0064] The airflow in the shell 3 mainly rotates around the center of the shell 3, and the annular area between the outer wall of the second quartz tube 43 and the inner wall of the shell 3 is the area where the airflow rotates upward. The ratio of the inner diameter of the shell 3 to the outer diameter of the second quartz tube 43 determines the size of the annular area. Further preferably, the ratio of the inner diameter of the shell 3 to the outer diameter of the second quartz tube 43 is 3 to 10:1. Within this range, the amount of powder and water vapor in the tail gas adhering to the outer wall of the second quartz tube 43 is minimal, which can minimize the cycle of cleaning the outer wall of the second quartz tube 43.

[0065] Typically but not limiting, the ratio of the inner diameter of the shell 3 to the outer diameter of the second quartz tube 43 may be 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1 or 10:1, or any ratio within the range of 3 to 10:1.

[0066] Furthermore, if Figure 4 As shown, the shell 3 is a cylindrical structure; the shell 3 includes a cylinder body 32, an upper cylinder cover 31 and a lower cylinder cover 33.

[0067] The cylinder 32 is provided with an air inlet 321 and an air outlet 322 . The air inlet 321 constitutes a passage for the fluid to enter the inner cavity of the cylinder 32 , and the air outlet 322 constitutes a passage for the fluid to leave the inner cavity of the cylinder 32 .

[0068] The central axis of the ultraviolet light emitting device 4 coincides with the central axis of the cylinder 32 .

[0069] like Figure 5 As shown, the air inlet 321 is disposed at the bottom of the cylinder 32 and is tangent to the cylinder 32 to form a centrifugal structure.

[0070] The air outlet 322 is disposed at the top of the cylinder 32 and is tangent to the cylinder 32 . The air outlet 322 and the air inlet 321 are disposed on different sides.

[0071] Furthermore, the air inlet 321 and the air outlet 322 are both square structures and are centrally symmetrical about the central axis of the cylinder 32 .

[0072] Among them, the ratio of the height to the width of the air inlet 321 is 1.5 to 3:1. The ratio of the height to the width of the air inlet 321 not only determines the flow pattern of the exhaust gas in the cylinder 32, but also determines the flow resistance of the exhaust gas in the cylinder 32. Under the same cross-sectional area of ​​the air inlet 321, the larger the ratio of the height to the width of the air inlet 321, the stronger the centrifugal force of the airflow in the cylinder 32, but the greater the flow resistance. Conversely, the smaller the ratio of the height to the width of the air inlet 321, the weaker the centrifugal force of the airflow in the cylinder 32, but the smaller the flow resistance. The best overall effect can be achieved by using a ratio of the height to the width of the air inlet 321 of 1.5 to 3:1.

[0073] Typically but not limiting, the ratio of the height to the width of the air inlet 321 can be 1.5:1, 1.6:1, 1.7:1, 1.8:1, 1.9:1, 2:1, 2.1:1, 2.2:1, 2.3:1, 2.4:1, 2.5:1, 2.6:1, 2.7:1, 2.8:1, 2.9:1 or 3:1, or any ratio within the range of 1.5 to 3:1.

[0074] The ratio of the width of the air inlet 321 to the inner diameter of the cylinder 32 is 0.10-0.25:1.

[0075] The ratio of the width of the air inlet 321 to the diameter of the cylinder 32 also has a great influence on the rotating flow field inside the cylinder 32. The smaller the ratio of the width of the air inlet 321 to the diameter of the cylinder 32, the greater the tangential velocity near the wall, but an unstable turbulent zone will be formed in the center of the cylinder 32. The larger the ratio of the width of the air inlet 321 to the diameter of the cylinder 32, the smaller the tangential velocity near the wall, but an unstable turbulent zone will also be formed in the center of the cylinder 32. Further preferably, the ratio of the width of the air inlet 321 to the diameter of the cylinder 32 is 0.10 to 0.25:1. Within this ratio range, there is basically no turbulent zone in the center of the cylinder 32, and dust and water vapor rarely enter the installation area of ​​the ultraviolet light emitting device 4 in the center of the cylinder 32 and have an adverse effect on the ultraviolet light emitting device 4.

[0076] Typically but not limiting, the ratio of the width of the air inlet 321 to the inner diameter of the barrel 32 can be 0.10:1, 0.11:1, 0.12:1, 0.13:1, 0.14:1, 0.15:1, 0.16:1, 0.17:1, 0.18:1, 0.19:1, 0.20:1, 0.21:1, 0.22:1, 0.23:1, 0.24:1 or 0.25:1, or it can be any ratio within the range of 0.10 to 0.25:1.

[0077] Furthermore, the upper cylinder cover 31 is disposed on the top of the cylinder body 32 and is disc-shaped.

[0078] A mounting tube 311 is disposed at the center of the upper cylinder cover 31 . The mounting tube 311 is used to mount and fix the ultraviolet light emitting device 4 . The mounting tube 311 connects the upper cylinder cover 31 with the inner cavity of the cylinder body 32 .

[0079] The lower cylinder cover 33 is disposed at the bottom of the cylinder body 32 .

[0080] like Figure 6 As shown, a drain pipe 331 is provided on the outer periphery of the upper cylinder cover 31; the drain pipe 331 is used to discharge the fluid processed by the ultraviolet catalytic decomposition device.

[0081] A second aspect of the present invention provides a tail gas treatment device, such as Figure 3 As shown, it comprises a cyclone separator 1, a cyclone water film dust collector 2 and the ultraviolet catalytic decomposition device described in the first aspect, which are connected in sequence;

[0082] The air inlet 321 of the ultraviolet catalytic decomposition device is connected to the output port of the cyclone water film dust collector 2;

[0083] The cyclone separator 1 is used to perform a primary dust removal on the initial exhaust gas to obtain a primary exhaust gas; the cyclone water film dust collector 2 is used to perform a secondary dust removal and organic gas absorption treatment on the primary exhaust gas to obtain a secondary exhaust gas; the ultraviolet light emitting device 4 is used to perform ultraviolet light catalytic decomposition treatment on the secondary exhaust gas in the shell 3 to obtain the final exhaust gas.

[0084] The tail gas treatment device provided by the present invention combines physical separation and chemical decomposition, adopts a multi-stage treatment mode, improves purification efficiency, avoids secondary pollution, and has a modular design for easy maintenance, thereby providing an efficient and environmentally friendly tail gas treatment method for industry.

[0085] Specifically, the exhaust gas treatment device of the present invention first uses a cyclone separator 1 to perform a dust removal on the initial exhaust gas, effectively removing large particle pollutants and generating primary exhaust gas. Subsequently, the primary exhaust gas enters the cyclone water film dust collector 2, where a more refined secondary dust removal and organic gas adsorption treatment are performed to further reduce the solid particles and organic pollutants in the exhaust gas, generating secondary exhaust gas. This stage of treatment not only improves the overall cleanliness of the exhaust gas, but also lays a good foundation for the subsequent ultraviolet photocatalytic decomposition.

[0086] The most critical link is that the secondary tail gas is introduced into the ultraviolet catalytic decomposition device, where the ultraviolet light emitting device 4 deeply treats the tail gas to obtain the final clean tail gas. This process not only completely purifies the tail gas, but also avoids the generation of secondary pollution.

[0087] The exhaust gas enters the cylinder 32 from the air inlet 321 and rotates upward under the action of centrifugal force. During the upward rotation of the exhaust gas, the powder and condensed water vapor in the exhaust gas are thrown toward the outer wall under the action of centrifugal force, and a negative pressure zone with very little dust and water vapor is formed in the center of the cylinder. The ultraviolet light emitting device 4 is arranged at the center of the shell 3, just in the area with the lowest concentration of dust and water vapor, avoiding the adverse effects of dust and water vapor in the exhaust gas on the ultraviolet light emitting device 4. The air inlet 321 and the air outlet 322 are both arranged tangentially to the cylinder, which can reduce the adverse effects of improper orientation of the air inlet 321 and the air outlet 322 on the air flow rotation flow field.

[0088] In the embodiment of the present invention, a pressure control system may be provided for the housing 3 to form the centrifugal structure, and the gas adhesion to the ultraviolet light emitting device 4 may be reduced by monitoring and adjusting the internal pressure of the housing 3. In addition, internal coating treatment may be performed, and the ultraviolet light emitting device 4 or the inner wall of the housing 3 may be subjected to special coating treatment to prevent the particles in the gas from accumulating on the ultraviolet light emitting device 4. For example, a material with a low friction coefficient may be used to reduce the resistance and adhesion of the gas during flow, or an anti-sticking material may be used.

[0089] The design of the entire tail gas treatment device fully considers the physical and chemical characteristics of pollutants, and achieves high efficiency and high purification of tail gas treatment through the organic combination of physical separation and chemical decomposition. In addition, the modular design of the device is also convenient for maintenance and upgrading, ensuring long-term stable operation.

[0090] The third aspect of the present invention provides a process for treating cross-linked tail gas, which is treated by using the tail gas treatment device described in the second aspect;

[0091] The cross-linking tail gas is generated during the production of vitamin A microcapsules;

[0092] The treatment process comprises the following steps: the cross-linked tail gas is subjected to a primary dust removal through a cyclone separator 1 to obtain a primary cross-linked tail gas; the primary cross-linked tail gas is further subjected to a secondary dust removal and a primary deodorization through a cyclone water film dust collector 2 to obtain a secondary cross-linked tail gas; the secondary cross-linked tail gas is subjected to a secondary deodorization through an ultraviolet catalytic decomposition device to obtain an odorless cross-linked tail gas.

[0093] The cross-linked tail gas treatment process provided by the present invention effectively removes dust and odor in the cross-linked tail gas generated in the production of vitamin A microcapsules in view of the beneficial effects brought by the tail gas treatment device. This process not only improves the cleanliness of the cross-linked tail gas, but also avoids secondary pollution, provides an efficient and environmentally friendly tail gas purification method for industrial production, and improves environmental quality.

[0094] Specifically, the cross-linked tail gas undergoes a dust removal in the cyclone separator 1, and the coarse particles are effectively separated, thereby obtaining the primary cross-linked tail gas. This preliminary treatment not only reduces the solid content in the tail gas, but also lays the foundation for subsequent fine processing. Subsequently, the primary cross-linked tail gas enters the cyclone water film dust collector 2, where secondary dust removal and primary deodorization are performed. The cyclone water film dust collector 2 uses water film technology to further capture tiny particles, and achieves preliminary deodorization through the chemical and physical effects of the water film, thereby producing secondary cross-linked tail gas. This step significantly improves the cleanliness of the tail gas and reduces the content of organic pollutants and odor molecules.

[0095] Finally, the secondary cross-linked tail gas is guided to the ultraviolet catalytic decomposition device for secondary deodorization. Under the irradiation of ultraviolet light, oxygen is catalyzed to be converted into ozone, and the strong oxidizing property of ozone is used to completely remove the odor, and finally obtain odorless cross-linked tail gas. The application of ultraviolet catalytic decomposition device not only ensures the thoroughness of tail gas treatment, but also avoids the generation of secondary pollution.

[0096] Furthermore, an absorbent is added into the cyclone water film dust collector 2 .

[0097] Preferably, the absorbent includes an aqueous solution of sodium hypochlorite, and the aldehyde substances in the cross-linking tail gas can be oxidized into carboxylic acids through the oxidation action of sodium hypochlorite and neutralized into sodium carboxylate, thereby reducing the load of subsequent ultraviolet light catalytic decomposition.

[0098] Preferably, the concentration of the sodium hypochlorite aqueous solution is 1.0-5.0 wt %, at which the odorous substances in the tail gas can be treated as cleanly as possible through the dual effects of chemical oxidation and physical absorption to reduce the load of subsequent ultraviolet photocatalytic decomposition.

[0099] Typically but not limiting, the concentration of the sodium hypochlorite aqueous solution can be 1.0wt%, 1.5wt%, 2.0wt%, 2.5wt%, 3.0wt%, 3.5wt%, 4.0wt%, 4.5wt% or 5.0wt%, or any concentration value within the range of 1.0 to 5.0wt%.

[0100] Furthermore, the ratio between the flow rate of the cross-linking tail gas and the power of the low-pressure mercury lamp 44 is 2000-5000 m 3 / h:1kW. The power of the ultraviolet lamp in the ultraviolet light emitting device 4 determines the treatment effect of the cross-linked tail gas. The lower the power of the ultraviolet lamp, the poorer the tail gas treatment effect. The higher the power of the ultraviolet lamp, the better the tail gas treatment effect, but it may waste electrical energy. The proportional relationship between the flow rate of the cross-linked tail gas and the power of the low-pressure mercury lamp 44 is between 2000 and 5000 m 3 / h:1kW range, it is possible to treat the special smell in the exhaust gas to make it odorless without wasting too much electricity.

[0101] Typically, but not limiting, the ratio between the flow rate of the crosslinking tail gas and the power of the low-pressure mercury lamp 44 may be 2000 m 3 / h:1kW, 2500m 3 / h:1kW、3000m 3 / h:1kW、3500m 3 / h:1kW, 4000m 3 / h:1kW、4500m 3 / h:1kW or 5000m 3 / h:1kW, can also be

[0102] 2000~5000m 3 / h: Any ratio within 1kW range.

[0103] Preferably, the wavelengths emitted by the low-pressure mercury lamp 44 are concentrated between 185 nm and 254 nm.

[0104] It has a good effect on decomposing small molecular aldehydes, ketones, hydrocarbons, degrading large molecular odorous substances, and killing bacteria and viruses.

[0105] Low-pressure mercury lamp 44 Further, the temperature of the cross-linking tail gas is 85-100° C., and the absolute humidity is 0.04-0.055 kg / kg.

[0106] Typically but not restrictively, the temperature of the cross-linked tail gas can be 85°C, 87°C, 90°C, 93°C, 96°C, 98°C or 100°C, or any temperature value within the range of 85 to 100°C; meanwhile, the absolute humidity of the cross-linked tail gas can be 0.04kg / kg, 0.042kg / kg, 0.044kg / kg, 0.046kg / kg, 0.048kg / kg, 0.05kg / kg, 0.052kg / kg, 0.054kg / kg or 0.055kg / kg, or any absolute humidity value within the range of 0.04 to 0.055kg / kg.

[0107] It should be noted that the absolute humidity unit "kg / kg" means how many kilograms of water vapor are included in each kilogram of absolute dry cross-linking tail gas. The water vapor content in each kilogram of absolute dry cross-linking tail gas of the present invention is 0.04-0.055 kg, which has a better treatment effect.

[0108] In the following, some embodiments of the present invention are described in detail in conjunction with the examples. In the absence of conflict, the following examples and features in the examples can be combined with each other. The raw materials in the following examples and comparative examples are purchased from the market unless otherwise specified.

[0109] Example 1

[0110] This embodiment provides a device for treating cross-linked tail gas generated in the production of vitamin A microcapsules. Figure 3 As shown, the cyclone separator 1, the cyclone water film dust collector 2 and the ultraviolet catalytic decomposition device described in the first aspect are connected in sequence; the air inlet 321 of the ultraviolet catalytic decomposition device is connected to the output port of the cyclone water film dust collector 2;

[0111] The ultraviolet catalytic decomposition device comprises a housing 3 and an ultraviolet light emitting device 4 arranged in the housing 3;

[0112] The ultraviolet light emitting device 4 is mainly composed of a low-pressure mercury lamp 44, a nitrogen tube 41, a first quartz tube 42 and a second quartz tube 43;

[0113] The first quartz tube 42 and the second quartz tube 43 are both structures with one end open and the other end closed;

[0114] The first quartz tube 42 is sleeved on the outside of the low-pressure mercury lamp 44, the nitrogen tube 41 is set in the gap between the first quartz tube 42 and the low-pressure mercury lamp 44, and the second quartz tube 43 is sleeved on the outside of the first quartz tube 42. The outer diameter of the second quartz tube 43 is 0.25m.

[0115] The housing 3 is a cylindrical structure, and comprises a cylinder 32, an upper cylinder cover 31 and a lower cylinder cover 33. The inner diameter of the cylinder 32 is 1.2 m, and the height is 1.5 m.

[0116] The cylinder 32 is provided with an air inlet 321 and an air outlet 322 . The air inlet 321 constitutes a passage for the fluid to enter the inner cavity of the cylinder 32 , and the air outlet 322 constitutes a passage for the fluid to leave the inner cavity of the cylinder 32 .

[0117] The central axis of the ultraviolet light emitting device 4 coincides with the central axis of the cylinder 32 .

[0118] The air inlet 321 is disposed at the bottom of the cylinder 32 and is tangent to the cylinder 32 to form a centrifugal structure.

[0119] The air outlet 322 is disposed at the top of the cylinder 32 and is tangent to the cylinder 32 . The air outlet 322 and the air inlet 321 are disposed on different sides.

[0120] Furthermore, the air inlet 321 and the air outlet 322 are both square structures, 0.4 m high and 0.2 m wide, and are centrally symmetrical about the central axis of the cylinder 32 .

[0121] The upper cylinder cover 31 is disposed on the top of the cylinder body 32 and is disc-shaped.

[0122] A mounting tube 311 is disposed at the center of the upper cylinder cover 31 . The mounting tube 311 is used to mount and fix the ultraviolet light emitting device 4 . The mounting tube 311 connects the upper cylinder cover 31 with the inner cavity of the cylinder body 32 .

[0123] The lower cylinder cover 33 is disposed at the bottom of the cylinder body 32 .

[0124] A drain pipe 331 is disposed on the outer periphery of the upper cylinder cover 31 ; the drain pipe 331 is used to discharge the liquid processed by the ultraviolet catalytic decomposition device.

[0125] Example 2

[0126] This embodiment provides a treatment process for cross-linked tail gas generated in the production of vitamin A microcapsules, which is carried out in the treatment device provided in Example 1. The treatment process is carried out according to the following steps:

[0127] 1. Add 20 kg of sodium hypochlorite and 1000 kg of tap water into the cyclone water film dust collector 2, and start the circulation pump for circulation.

[0128] 2. Open the exhaust outlet 322 induced draft fan of the ultraviolet light emitting device 4, open the nitrogen inlet valve of the ultraviolet light emitting device 4, and introduce high-purity nitrogen into the ultraviolet light emitting device 4, setting the nitrogen flow rate to 3L / min. Set the power of the low-pressure mercury lamp 44 to 1.0kW, and turn on the low-pressure mercury lamp 44 of the ultraviolet light emitting device 4.

[0129] 3. The cross-linking tail gas flow rate is 4489m 3 / h, odor index was 4678, temperature was 92°C, and absolute humidity was 0.047kg / kg. The cross-linking tail gas was connected to the inlet of the cyclone separator 1 in the treatment device provided in Example 1 for tail gas treatment.

[0130] After testing, the odor index (dimensionless) of the exhaust gas at the outlet of cyclone separator 1 is 4536; the odor index of the exhaust gas at the outlet of cyclone water film dust collector 2 is 3245; and the odor index (dimensionless) of the outlet 322 of the ultraviolet catalytic decomposition device is 10.

[0131] The odor index is a dimensionless parameter, which is characterized by measuring the dilution factor of the exhaust gas sample. The specific operation is: the exhaust gas sample is gradually diluted and then detected by the electronic nose. When the electronic nose can no longer detect the odor, the dilution factor of the sample is recorded, and this value is the odor index.

[0132] Example 3

[0133] This embodiment provides a treatment process for cross-linked tail gas generated in the production of vitamin A microcapsules, which is carried out in the treatment device provided in Example 1. The treatment process is carried out according to the following steps:

[0134] 1. Add 10 kg of sodium hypochlorite and 1000 kg of tap water into the cyclone water film dust collector 2, and start the circulation pump for circulation.

[0135] 2. This step is the same as in Example 2.

[0136] 3. The cross-linking tail gas flow rate is 4567m 3 / h, odor index was 4964, temperature was 92°C, and absolute humidity was 0.05kg / kg. The cross-linking tail gas was connected to the inlet of the cyclone separator 1 in the treatment device provided in Example 1 for tail gas treatment.

[0137] After testing, the odor index (dimensionless) of the exhaust gas at the outlet of cyclone separator 1 is 4854; the odor index of the exhaust gas at the outlet of cyclone water film dust collector 2 is 4378; and the odor index (dimensionless) of the outlet 322 of the ultraviolet catalytic decomposition device is 12.

[0138] Example 4

[0139] This embodiment provides a treatment process for cross-linked tail gas generated in the production of vitamin A microcapsules, which is carried out in the treatment device provided in Example 1. The treatment process is carried out according to the following steps:

[0140] 1. Add 53 kg of sodium hypochlorite and 1000 kg of tap water into the cyclone water film dust collector 2, and start the circulation pump for circulation.

[0141] 2. This step is the same as in Example 2.

[0142] 3. The cross-linking tail gas flow rate is 4523m 3 / h, the odor index was 4723, the temperature was 92°C, and the absolute humidity was 0.046kg / kg. The cross-linking tail gas was connected to the inlet of the cyclone separator 1 in the treatment device provided in Example 1 for tail gas treatment.

[0143] After testing, the odor index (dimensionless) of the exhaust gas at the outlet of cyclone separator 1 is 4536; the odor index of the exhaust gas at the outlet of cyclone water film dust collector 2 is 3124; and the odor index (dimensionless) of the outlet 322 of the ultraviolet catalytic decomposition device is 17.

[0144] Example 5

[0145] This embodiment provides a treatment process for cross-linked tail gas generated in the production of vitamin A microcapsules, which is carried out in the treatment device provided in Example 1. The treatment process is carried out according to the following steps:

[0146] 1. Same as the step in Example 2.

[0147] 2. Open the exhaust outlet 322 induced draft fan of the ultraviolet light emitting device 4, open the nitrogen inlet valve of the ultraviolet light emitting device 4, and introduce high-purity nitrogen into the ultraviolet light emitting device 4, setting the nitrogen flow rate to 3L / min. Set the power of the low-pressure mercury lamp 44 to 2.0kW, and turn on the low-pressure mercury lamp 44 of the ultraviolet light emitting device 4.

[0148] 3. The cross-linking tail gas flow rate is 4512m 3 / h, odor index was 4712, temperature was 92°C, and absolute humidity was 0.047kg / kg. The cross-linking tail gas was connected to the inlet of the cyclone separator 1 in the treatment device provided in Example 1 for tail gas treatment.

[0149] After testing, the odor index (dimensionless) of the exhaust gas at the outlet of cyclone separator 1 is 4511; the odor index of the exhaust gas at the outlet of cyclone water film dust collector 2 is 3324; and the odor index (dimensionless) of the outlet 322 of the ultraviolet catalytic decomposition device is 2.

[0150] Example 6

[0151] This embodiment provides a treatment process for cross-linked tail gas generated in the production of vitamin A microcapsules, which is carried out in the treatment device provided in Example 1. The treatment process is carried out according to the following steps:

[0152] 1. Add 1000 kg of tap water into the cyclone water film dust collector 2 and start the circulation pump for circulation.

[0153] 2. Same as the step in Example 2.

[0154] 3. The cross-linking tail gas flow rate is 4475m 3 / h, odor index was 4529, temperature was 92°C, and absolute humidity was 0.049kg / kg. The cross-linking tail gas was connected to the inlet of the cyclone separator 1 in the treatment device provided in Example 1 for tail gas treatment.

[0155] After testing, the odor index (dimensionless) of the exhaust gas at the outlet of cyclone separator 1 is 4413; the odor index of the exhaust gas at the outlet of cyclone water film dust collector 2 is 4211; and the odor index (dimensionless) of the outlet 322 of the ultraviolet catalytic decomposition device is 69.

[0156] Example 7

[0157] This embodiment provides a treatment process for cross-linked tail gas generated in the production of vitamin A microcapsules, which is carried out in the treatment device provided in Example 1. The treatment process is carried out according to the following steps:

[0158] 1. Add 75 kg of sodium hypochlorite and 1000 kg of tap water into the cyclone water film dust collector 2, and start the circulation pump for circulation.

[0159] 2. Same as the step in Example 2.

[0160] 3. The cross-linking tail gas flow rate is 4534m 3 / h, odor index is 4658, temperature is 92°C, and absolute humidity is 0.047kg / kg. The cross-linking tail gas is connected to the inlet of the cyclone separator 1 in the treatment device provided in Example 1 for tail gas treatment.

[0161] After testing, the odor index (dimensionless) of the exhaust gas at the outlet of cyclone separator 1 is 4538; the odor index of the exhaust gas at the outlet of cyclone water film dust collector 2 is 3057; and the odor index (dimensionless) of the outlet 322 of the ultraviolet catalytic decomposition device is 88.

[0162] Example 8

[0163] This embodiment provides a treatment process for cross-linked tail gas generated in the production of vitamin A microcapsules, which is carried out in the treatment device provided in Example 1. The treatment process is carried out according to the following steps:

[0164] 1. Add 20 kg of sodium hypochlorite and 1000 kg of tap water into the cyclone water film dust collector 2, and start the circulation pump for circulation.

[0165] 2. Open the exhaust outlet 322 induced draft fan of the ultraviolet light emitting device 4, open the nitrogen inlet valve of the ultraviolet light emitting device 4, and introduce high-purity nitrogen into the ultraviolet light emitting device 4, setting the nitrogen flow rate to 3L / min. Set the power of the low-pressure mercury lamp 44 to 0.5kW, and turn on the low-pressure mercury lamp 44 of the ultraviolet light emitting device 4.

[0166] 3. The cross-linking tail gas flow rate is 4524m 3 / h, the odor index was 4713, the temperature was 92°C, and the absolute humidity was 0.046kg / kg. The cross-linking tail gas was connected to the inlet of the cyclone separator 1 in the treatment device provided in Example 1 for tail gas treatment.

[0167] After testing, the odor index (dimensionless) of the exhaust gas at the outlet of cyclone separator 1 is 4540; the odor index of the exhaust gas at the outlet of cyclone water film dust collector 2 is 3245; and the odor index (dimensionless) of the outlet 322 of the ultraviolet catalytic decomposition device is 68.

[0168] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An ultraviolet photocatalytic decomposition device, characterized in that: It comprises a shell and an ultraviolet light emitting device arranged in the shell; The ultraviolet light emitting device is mainly composed of a low-pressure mercury lamp, a nitrogen tube, a first quartz tube and a second quartz tube; The first quartz tube and the second quartz tube are both structures with one end open and the other end closed; The first quartz tube is sleeved outside the low-pressure mercury lamp, the nitrogen tube is arranged in the gap between the first quartz tube and the low-pressure mercury lamp, and the second quartz tube is sleeved outside the first quartz tube.

2. The ultraviolet photocatalytic decomposition device according to claim 1, characterized in that: The ratio of the inner diameter of the shell to the outer diameter of the second quartz tube is 3 to 10:

1.

3. The ultraviolet photocatalytic decomposition device according to claim 1, characterized in that: The shell is a cylindrical structure; the shell comprises a cylinder body, an upper cylinder cover and a lower cylinder cover; The cylinder is provided with an air inlet and an air outlet; The central axis of the ultraviolet light emitting device coincides with the central axis of the cylinder; The air inlet is arranged at the bottom of the cylinder and is tangent to the cylinder to form a centrifugal structure; The air outlet is arranged at the top of the cylinder and is tangent to the cylinder, and the air outlet and the air inlet are arranged on different sides.

4. The ultraviolet light catalytic decomposition device according to claim 3, characterized in that: The air inlet and the air outlet are both square structures and are centrally symmetrical about the central axis of the cylinder; Wherein, the ratio of the height to the width of the air inlet is 1.5 to 3:1; The ratio of the width of the air inlet to the inner diameter of the cylinder is 0.10-0.25:

1.

5. The ultraviolet light catalytic decomposition device according to claim 3, characterized in that: The upper cylinder cover is arranged on the top of the cylinder; A mounting tube is provided at the center of the upper cylinder cover, and the mounting tube is used to mount and fix the ultraviolet light emitting device; The lower cylinder cover is arranged at the bottom of the cylinder; A drain pipe is provided on the outer periphery of the lower cylinder cover; the drain pipe is used to discharge the liquid accumulated in the ultraviolet catalytic decomposition device.

6. An exhaust gas treatment device, characterized in that: It comprises a cyclone separator, a cyclone water film dust collector and an ultraviolet catalytic decomposition device according to any one of claims 1 to 5 which are connected in sequence; The air inlet of the ultraviolet catalytic decomposition device is connected to the output port of the cyclone water film dust collector; The cyclone separator is used to perform a primary dust removal on the initial exhaust gas to obtain a primary exhaust gas; the cyclone water film dust collector is used to perform a secondary dust removal and organic gas absorption treatment on the primary exhaust gas to obtain a secondary exhaust gas; the ultraviolet light emitting device is used to perform ultraviolet light catalytic decomposition treatment on the secondary exhaust gas in the shell to obtain the final exhaust gas.

7. A process for treating cross-linked tail gas, characterized in that: The tail gas treatment device according to claim 6 is used for treatment; The cross-linking tail gas is generated during the production of vitamin A microcapsules; The treatment process The method comprises the following steps: the cross-linked tail gas is subjected to primary dust removal through a cyclone separator to obtain primary cross-linked tail gas; the primary cross-linked tail gas is further subjected to secondary dust removal and primary deodorization through a cyclone water film dust collector to obtain secondary cross-linked tail gas; The secondary cross-linked tail gas is subjected to secondary deodorization by an ultraviolet light catalytic decomposition device to obtain odorless cross-linked tail gas.

8. The treatment process according to claim 7, characterized in that: An absorbent is added into the cyclone water film dust collector; Preferably, the absorbent comprises an aqueous solution of sodium hypochlorite; Preferably, the concentration of the sodium hypochlorite aqueous solution is 1.0-5.0 wt %.

9. The treatment process according to claim 7, characterized in that: The ratio between the flow rate of the cross-linked tail gas and the power of the low-pressure mercury lamp is 2000-5000m 3 / h:1kW.

10. The treatment process according to claim 7, characterized in that: The temperature of the cross-linking tail gas is 85-100° C., and the absolute humidity is 0.04-0.055 kg / kg.

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