Food-grade dry ice tail gas carbon dioxide recycling device and method thereof

Abstract

This invention discloses a device and method for recovering and reusing carbon dioxide from food-grade dry ice exhaust gas, belonging to the field of carbon dioxide recovery technology. It includes a duct assembly with a pipe for introducing dry ice exhaust gas; a carbon dioxide liquefaction device for liquefying the dry ice exhaust gas into liquid carbon dioxide; an exhaust gas diversion structure located within the duct for generating a diversion airflow; an exhaust gas storage mechanism for temporarily storing redundant dry ice exhaust gas; and a flow rate adaptive adjustment component. By incorporating the exhaust gas storage mechanism and the flow rate adaptive adjustment component, this invention can adaptively adjust the diversion volume of the exhaust gas diversion structure according to changes in air pressure within the storage mechanism. This maintains the flow rate of dry ice exhaust gas entering the carbon dioxide liquefaction device at a stable level, avoiding sudden increases in load or insufficient air intake in the liquefaction equipment caused by instantaneous fluctuations in the dry ice exhaust gas flow rate, thus improving the stability and efficiency of carbon dioxide liquefaction and recovery.

Description

Technical Field

[0001] The present invention belongs to the technical field of carbon dioxide recovery, and specifically relates to a food-grade dry ice tail gas carbon dioxide recovery and reuse device and method thereof. Background Art

[0002] Dry ice (solid carbon dioxide) is widely used in food-grade fields such as food refrigeration, cold chain transportation, food cleaning and industrial fresh-keeping due to its non-toxic, odorless, low-temperature refrigeration and pollution-free characteristics. In the industrial preparation process of food-grade dry ice, liquid carbon dioxide needs to undergo high-pressure throttling and solidification molding processes. However, affected by factors such as process pressure difference, equipment pressure relief and molding loss, a large amount of unsolidified carbon dioxide tail gas will be generated in this process. This part of the tail gas is a high-quality food-grade carbon dioxide gas source. If directly discharged, it will not only cause serious waste of raw materials and greatly increase the raw material cost of dry ice production, but also increase greenhouse gas emissions, which is not conducive to energy conservation, environmental protection and green production.

[0003] At present, the structure and function of the carbon dioxide recovery equipment supporting the existing food-grade dry ice production are relatively single. Specifically, most of the existing recovery systems adopt an operation mode of constant air volume induced draft collection combined with direct liquefaction recovery. This mode cannot perform adaptive adjustment according to the instantaneous exhaust volume of dry ice tail gas. Since the tail gas emission during the dry ice preparation process is an intermittent and fluctuating gas flow, the instantaneous exhaust volume varies greatly. When the instantaneous discharge amount of tail gas is too large, the constant induced draft structure cannot perform shunting and pressure stabilization in time, resulting in a large amount of tail gas rushing into the liquefaction device instantaneously, causing a sharp increase in the intake load of the liquefaction equipment and causing fluctuations in liquefaction pressure and temperature parameters. This will not only reduce the liquefaction recovery rate of carbon dioxide, but also easily lead to overload operation of the liquefaction equipment and affect its service life. At the same time, the excess tail gas that has not had time to be liquefied often needs to be relieved and discharged, resulting in waste of raw materials.

[0004] In summary, the existing food-grade dry ice carbon dioxide tail gas recovery technology has defects such as poor gas flow adaptability, lack of buffer energy storage structure, and inability to realize adaptive air volume adjustment, and it is difficult to meet the large-scale, high-precision and low-loss production requirements of food-grade dry ice.

[0005] Therefore, it is necessary to develop a new type of food-grade dry ice tail gas carbon dioxide recovery and reuse device and method thereof to solve the above-mentioned deficiencies existing in the prior art. Contents of the Invention

[0006] In view of the above situation, in order to overcome the defects of the prior art, the present invention provides a food-grade dry ice tail gas carbon dioxide recovery and reuse device and method thereof, which effectively solves the problems existing in the current market.

[0007] The technical solution adopted by this invention is as follows: This invention provides a food-grade dry ice exhaust carbon dioxide recovery and reuse device, including a duct assembly, a carbon dioxide liquefaction device, an exhaust gas diversion structure, an exhaust gas temporary storage mechanism, and a flow adaptive adjustment component. The duct assembly has a duct for introducing dry ice exhaust gas. The carbon dioxide liquefaction device is connected to the outlet end of the duct and is used to liquefy the dry ice exhaust gas into liquid carbon dioxide. The exhaust gas diversion structure is disposed inside the duct and is used to generate a diverted airflow. The exhaust gas temporary storage mechanism is connected to the duct and is used to temporarily store redundant dry ice exhaust gas. The flow adaptive adjustment component is connected to both the exhaust gas temporary storage mechanism and the exhaust gas diversion structure, and is used to adjust the diversion volume of the exhaust gas diversion structure according to the pressure change within the exhaust gas temporary storage mechanism, so that the flow rate of dry ice exhaust gas entering the carbon dioxide liquefaction device remains stable.

[0008] Furthermore, the air duct assembly also includes a guide plate disposed inside the air duct, the guide plate being rotatably disposed, and its opening and closing distance adaptively changing with the instantaneous flow rate of dry ice exhaust gas inside the air duct.

[0009] Furthermore, the air duct assembly also includes a movable baffle and a transmission rod. The movable baffle is slidably disposed on the side wall of the air duct. One end of the transmission rod is hinged to the guide plate, and the other end is hinged to the movable baffle. The guide plate drives the movable baffle to slide through the transmission rod to control the opening and closing of the ventilation opening between the air duct and the exhaust gas storage mechanism.

[0010] Furthermore, the exhaust gas storage mechanism includes a gas storage box and a sliding plate slidably disposed in the gas storage box. The sliding plate divides the gas storage box into a gas chamber and a spring chamber. A return spring is provided in the spring chamber. One end of the return spring is connected to the sliding plate, and the other end is connected to the inner wall of the fixed sleeve. The sliding plate is slidably connected in the fixed sleeve.

[0011] Furthermore, the exhaust gas diversion structure includes a fan motor, a drive shaft, and fan blades. The drive shaft is connected to the output end of the fan motor, and the fan blades are rotatably mounted on the drive shaft, with the deflection angle of the fan blades being adjustable.

[0012] Furthermore, the flow adaptive adjustment component includes a rotating rod, a support shaft, and a hinge rod. The middle part of the rotating rod is rotatably sleeved on the support shaft to form a lever structure. The first end of the rotating rod is linked to the sliding plate in the exhaust gas storage mechanism, and the second end of the rotating rod is connected to the exhaust gas diversion structure through the hinge rod.

[0013] Furthermore, the distance between the first end of the rotating rod and the support shaft is greater than the distance between the second end of the rotating rod and the support shaft, so as to form a force-saving lever structure.

[0014] Furthermore, the exhaust gas diversion structure also includes a sliding ring and a linkage rod. The sliding ring is slidably sleeved on the drive shaft and connected to the fan blade. One end of the linkage rod is rotatably connected to the hinge rod, and the other end is slidably connected to the sliding ring. The rotating rod drives the sliding ring to slide along the drive shaft through the hinge rod and the linkage rod to adjust the deflection angle of the fan blade.

[0015] Furthermore, the flow adaptive adjustment component also includes a torsion spring, which is sleeved on the support shaft and has its two ends connected to the support shaft and the rotating rod, respectively.

[0016] This invention also provides a method for recovering and reusing carbon dioxide from food-grade dry ice exhaust gas, using the apparatus described in any of the above-mentioned methods, comprising the following steps: S1, activating the exhaust gas diversion structure to introduce dry ice exhaust gas generated by the dry ice preparation equipment into the duct; S2, the dry ice exhaust gas is transported through the duct to a carbon dioxide liquefaction device for liquefaction treatment to obtain liquid carbon dioxide; S3, when the instantaneous flow rate of the dry ice exhaust gas in the duct exceeds a preset threshold, a portion of the dry ice exhaust gas is diverted into the exhaust gas temporary storage mechanism for temporary storage. Simultaneously, the pressure change in the exhaust gas temporary storage mechanism drives the flow adaptive adjustment component to operate, thereby reducing the air volume diverted by the exhaust gas diversion structure; S4, when the instantaneous flow rate of the dry ice exhaust gas in the duct is lower than the preset threshold, the dry ice exhaust gas stored in the exhaust gas temporary storage mechanism is released back into the duct for continued transport. Simultaneously, the flow adaptive adjustment component is reset, thereby increasing the air volume diverted by the exhaust gas diversion structure.

[0017] The beneficial effects achieved by the present invention using the above structure are as follows:

[0018] (1) By setting up a tail gas storage mechanism and a flow adaptive adjustment component, the air volume of the tail gas diversion structure can be adaptively adjusted according to the gas pressure change in the tail gas storage mechanism, thereby maintaining the dry ice tail gas flow rate entering the carbon dioxide liquefaction device at a stable level, avoiding the problem of sudden increase in load or insufficient air intake of the liquefaction equipment caused by instantaneous flow fluctuation of dry ice tail gas, and improving the stability and efficiency of carbon dioxide liquefaction recovery.

[0019] (2) By setting an adaptively adjustable guide plate in the duct and controlling the opening and closing of the vent with a linkage baffle, when the instantaneous flow rate of dry ice exhaust gas is too large, the redundant exhaust gas is automatically diverted into the exhaust gas storage mechanism for temporary storage, which effectively buffers the instantaneous airflow peak pressure; when the exhaust gas flow rate drops, the stored exhaust gas is released back into the air duct to replenish the flow, ensuring the continuity of air intake, thereby solving the problem of recycling caused by the intermittent and fluctuating emission of dry ice exhaust gas and reducing the waste of raw materials.

[0020] (3) By adopting a lever-type linkage mechanism consisting of a rotating rod, a support shaft, a hinge rod, a sliding ring and a linkage rod, the small displacement of the sliding plate in the exhaust gas storage mechanism is amplified and transmitted to the fan blades, and the fan blade deflection angle is precisely adjusted. Thus, the air volume is dynamically adjusted under the premise that the speed of the induced draft motor remains unchanged, which realizes sensitive and precise control of the intake air volume, further improves the airflow stability and reduces the energy consumption of the equipment. Attached Figure Description

[0021] Figure 1 A schematic diagram of the overall structure of a food-grade dry ice exhaust carbon dioxide recovery and reuse device. Figure 1 ;

[0022] Figure 2 A schematic diagram of the overall structure of a food-grade dry ice exhaust carbon dioxide recovery and reuse device. Figure 2 ;

[0023] Figure 3 A schematic diagram of the flow adaptive adjustment component of a food-grade dry ice exhaust carbon dioxide recovery and reuse device.

[0024] Figure 4 This is a schematic diagram of the internal structure of a food-grade dry ice exhaust carbon dioxide recovery and reuse device.

[0025] Figure 5 A partial structural diagram of a food-grade dry ice exhaust carbon dioxide recovery and reuse device. Figure 1 ;

[0026] Figure 6 A schematic diagram of the exhaust gas diversion structure;

[0027] Figure 7 for Figure 6 Enlarged view of the structure at point A in the middle;

[0028] Figure 8 This is an exploded view of the exhaust gas storage mechanism.

[0029] The components include: 1. Duct assembly; 101. Duct; 102. Rotating shaft; 103. Guide plate; 104. Movable baffle; 105. Ventilation outlet; 106. Transmission rod; 2. Carbon dioxide liquefaction device; 3. Exhaust gas diversion structure; 301. Connecting shell; 302. Support mesh plate; 303. Exhaust fan motor; 304. Drive shaft; 305. Fixed base; 306. Fan blade; 307. Sliding ring; 308. Connecting shaft; 309. Linkage rod; 4. Exhaust gas temporary storage mechanism; 401. Gas storage box; 402. Fixed sleeve; 403. Sliding plate; 404. Return spring; 5. Flow adaptive adjustment component; 501. Protective cover; 502. Rotating rod; 503. Support shaft; 504. Torsion spring; 505. Hinge rod.

[0030] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof. Detailed Implementation

[0031] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0032] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0033] The core of this invention is to provide a device and method for recovering and reusing carbon dioxide from food-grade dry ice exhaust gas. The device includes a duct assembly 1, a carbon dioxide liquefaction device 2, an exhaust gas diversion structure 3, an exhaust gas temporary storage mechanism 4, and a flow adaptive adjustment assembly 5.

[0034] Through the coordinated operation of various components, the system can adaptively adjust the flow rate of dry ice exhaust gas according to the instantaneous flow rate, buffer the peak flow rate, and stabilize the intake load of the liquefaction unit. This significantly improves the carbon dioxide liquefaction recovery rate and equipment operation stability, effectively solving the problems of poor airflow adaptability, lack of buffer energy storage structure, and inability to adaptively adjust air volume in existing exhaust gas recovery devices.

[0035] Please see Figures 1 to 8 As shown, the present invention provides a food-grade dry ice exhaust carbon dioxide recovery and reuse device, including a duct assembly 1, a carbon dioxide liquefaction device 2, an exhaust gas diversion structure 3, an exhaust gas temporary storage mechanism 4, and a flow adaptive adjustment component 5.

[0036] The air duct assembly 1 has a channel inside for the dry ice exhaust gas to flow.

[0037] The carbon dioxide liquefaction device 2 is connected to the outlet end of the air duct assembly 1 and is used to liquefy the dry ice tail gas into liquid carbon dioxide.

[0038] The exhaust gas diversion structure 3 is disposed within the air duct assembly 1 and is used to generate an airflow that introduces dry ice exhaust gas into the air duct assembly 1. The exhaust gas temporary storage mechanism 4 is connected to the air duct assembly 1 and is used to temporarily store redundant dry ice exhaust gas.

[0039] The flow adaptive adjustment component 5 is linked to the exhaust gas storage mechanism 4 and the exhaust gas diversion structure 3 respectively.

[0040] The air duct assembly 1 includes an openable and closable guide plate 103. The guide plate 103 adjusts the opening and closing distance according to the dry ice exhaust gas flow rate entering the air duct assembly 1 to control the connection state between the air duct assembly 1 and the exhaust gas storage mechanism 4. The exhaust gas storage mechanism 4 drives the flow rate adaptive adjustment component 5 according to its internal air pressure. The flow rate adaptive adjustment component 5 adjusts the air volume of the exhaust gas diversion structure 3 according to the air pressure to keep the dry ice exhaust gas flow rate entering the carbon dioxide liquefaction device 2 stable.

[0041] Specifically, the air duct assembly 1 serves as the main flow path for dry ice exhaust gas, and its internal guide plate 103 is the core flow sensing and diversion control element.

[0042] When the dry ice exhaust gas flow rate is low, the guide plate 103 is closed or slightly open, and the connection between the exhaust gas storage mechanism 4 and the air duct assembly 1 is closed, with all exhaust gas flowing directly to the carbon dioxide liquefaction device 2. When the dry ice exhaust gas flow rate increases, the impact force of the airflow on the guide plate 103 increases, pushing the guide plate 103 to open, and the opening and closing distance increases accordingly. The opening and closing action of the guide plate 103 is linked to control the connection state between the air duct assembly 1 and the exhaust gas storage mechanism 4, allowing some redundant exhaust gas to be diverted into the exhaust gas storage mechanism 4 for temporary storage.

[0043] The air pressure inside the exhaust gas storage mechanism 4 increases as the amount of stored gas increases, and this air pressure acts as a driving signal to the flow adaptive adjustment component 5.

[0044] The flow adaptive adjustment component 5 adjusts the exhaust gas flow rate of the exhaust gas diversion structure 3 according to the gas pressure, for example, by reducing the exhaust gas flow rate, thereby reducing the total amount of exhaust gas drawn in from the dry ice preparation equipment, so that the dry ice exhaust gas flow rate entering the carbon dioxide liquefaction device 2 is kept within a relatively stable range.

[0045] This setup, through mechanical linkage feedback, enables adaptive adjustment of intermittent and fluctuating exhaust emissions, eliminating the need for a complex electronic control system. It is structurally reliable and responds quickly.

[0046] When in use, connect this device to the exhaust port of the dry ice preparation equipment.

[0047] The exhaust gas diversion structure 3 is activated, generating negative pressure to draw dry ice exhaust gas into the air duct assembly 1.

[0048] The exhaust gas flows through the guide vane 103, and the guide vane 103 automatically adjusts its opening according to the instantaneous flow rate.

[0049] When the exhaust gas flow exceeds the preset threshold, the deflector 103 opens, and the vent 105 opens in conjunction with it, allowing some of the exhaust gas to enter the exhaust gas storage mechanism 4 for storage.

[0050] The air pressure inside the exhaust gas storage mechanism 4 increases, driving the flow adaptive adjustment component 5 to operate and reduce the exhaust gas diversion volume of the exhaust gas diversion structure 3.

[0051] When the exhaust gas flow rate drops, the exhaust gas storage mechanism 4 releases the stored exhaust gas, and at the same time, the flow adaptive adjustment component 5 reverses its action to increase the induced draft.

[0052] Finally, the stable exhaust gas flow enters the carbon dioxide liquefaction unit 2, where it is liquefied into liquid carbon dioxide and returned to the dry ice preparation equipment for recycling. This process effectively buffers the gas flow peak, ensures a stable intake load for the liquefaction unit, avoids liquefaction parameter disorder and equipment overload caused by intake fluctuations, and significantly improves the carbon dioxide liquefaction recovery rate and liquefaction purity.

[0053] Based on the above embodiments, the air duct assembly 1 further includes an air duct 101 and a rotating shaft 102, and multiple guide plates 103 are provided. The multiple guide plates 103 are arranged at intervals along the circumference of the air duct 101, and each guide plate 103 can rotate around the rotating shaft 102.

[0054] Specifically, the duct 101 is the main duct for exhaust gas flow, and its cross-sectional shape can be circular, rectangular or other suitable shapes. This application does not make specific limitations on this. The rotating shaft 102 is arranged radially along the duct 101. One end of each guide plate 103 is rotatably connected to the rotating shaft 102, and the other end is a free end. When the airflow passes through, the airflow pressure acts on the plate surface of the guide plate 103, causing it to rotate around the rotating shaft 102, thereby changing the opening and closing distance between the guide plates 103.

[0055] Furthermore, the air duct assembly 1 also includes a movable baffle 104 and a transmission rod 106. The movable baffle 104 is slidably disposed on the air duct 101 and is used to open or close the ventilation port 105 between the air duct 101 and the exhaust gas storage mechanism 4. One end of the transmission rod 106 is connected to the guide plate 103 and the other end is connected to the movable baffle 104, and is used to drive the movable baffle 104 to slide when the guide plate 103 rotates.

[0056] Specifically, the vent 105 is opened on the side wall of the duct 101 and is a channel connecting the duct 101 and the exhaust gas storage mechanism 4. The movable baffle 104 covers the vent 105 and can slide along the duct 101. The transmission rod 106 is a mechanical linkage component, with one end connected to one of the guide plates 103 and the other end connected to the movable baffle 104. When the guide plate 103 rotates and opens due to increased airflow, the movable baffle 104 is driven to slide through the pushing and pulling action of the transmission rod 106, thereby opening the vent 105 and allowing some exhaust gas to be diverted into the exhaust gas storage mechanism 4. When the guide plate 103 returns to its original position, the transmission rod 106 drives the movable baffle 104 to slide in the opposite direction, closing the vent 105. Preferably, a return spring (not shown in the figure) can be provided between the movable baffle 104 and the air duct 101 to help the movable baffle 104 remain closed when there is no external force. The transmission rod 106 can be a rigid rod, and its connection method is hinged. As long as it can realize the conversion of the rotation of the guide plate 103 into the linear sliding of the movable baffle 104, this application does not make a unique limitation on the specific structure and connection method of the transmission rod 106.

[0057] Based on the above embodiments, the exhaust gas storage mechanism 4 further includes an air storage box 401 and a sliding plate 403 slidably disposed in the air storage box 401. The sliding plate 403 divides the interior of the air storage box 401 into an air storage chamber and a reset chamber. A reset spring 404 is disposed in the reset chamber. One end of the reset spring 404 is fixedly connected to the sliding plate 403 for driving the sliding plate 403 to reset.

[0058] Specifically, the gas storage box 401 is a sealed container used to temporarily store excess dry ice exhaust gas. The sliding plate 403 is sealed and slidably fitted to the inner wall of the gas storage box 401, dividing the interior of the gas storage box 401 into two independent chambers: a gas storage chamber connected to the vent 105, and a closed reset chamber. A reset spring 404 is disposed in the reset chamber, with one end fixedly connected to the inner wall of the fixed sleeve 402 and the other end fixedly connected to the sliding plate 403. When the gas pressure in the gas storage chamber increases, the gas pressure pushes the sliding plate 403 towards the reset chamber, compressing the reset spring 404, increasing the volume of the gas storage chamber and thus storing more gas. When the gas pressure in the gas storage chamber decreases, the reset spring 404 releases its elastic potential energy, pushing the sliding plate 403 to slide in the opposite direction, thus retrieving the exhaust gas. The gas stored in the gas storage chamber is pushed back to the air duct 101 through the vent 105. With this configuration, the exhaust gas temporary storage mechanism 4 not only achieves temporary gas storage, but also converts the gas pressure change into mechanical displacement through the displacement of the sliding plate 403, providing a power source for driving the flow adaptive adjustment component 5. It should be noted that the material and sealing method of the sliding plate 403 can be selected according to the working pressure, such as using a rubber sealing ring or piston ring to ensure good airtightness. The elastic coefficient of the return spring 404 can be selected according to the required gas pressure adjustment range. This application does not make specific limitations on this. In another optional embodiment, the exhaust gas temporary storage mechanism 4 can also adopt an airbag type or a bellows type structure, as long as it can realize the functions of gas storage and pressure-displacement conversion.

[0059] Furthermore, the flow adaptive adjustment component 5 includes a rotating rod 502, a support shaft 503, and a hinge rod 505. The rotating rod 502 is rotatably mounted on the support shaft 503, and the support shaft 503 is located at a non-central position of the rotating rod 502, so that the rotating rod 502 forms a lever structure. One end of the rotating rod 502 abuts against or connects to the sliding plate 403, and the other end is linked to the exhaust gas diversion structure 3 through the hinge rod 505.

[0060] Specifically, the support shaft 503 is fixedly mounted on the protective cover 501, and the rotating rod 502 is sleeved on the support shaft 503 at a non-central position, forming a lever. The support shaft 503 divides the rotating rod 502 into a long arm end and a short arm end. The displacement of the sliding plate 403 is transmitted to the long arm end of the rotating rod 502 through abutment or connection. Due to the lever principle, a large displacement of the long arm end will result in a reduced displacement at the short arm end. The short arm end is connected to the exhaust gas diversion structure 3 through a hinge rod 505. When the sliding plate 403 pushes the long arm end of the rotating rod 502, the short arm end drives the hinge rod 505 to move, thereby driving the exhaust gas diversion structure 3 to adjust. Preferably, a torsion spring 504 can be provided on the support shaft 503 to provide a restoring force for the rotating rod 502, so that it maintains its initial position when no external force is applied. With this configuration, the reduction of displacement by the lever causes a large displacement of the sliding plate 403 within the exhaust gas storage mechanism 4, which in turn drives the exhaust gas diversion structure 3 to adjust. It should be noted that the lever ratio (i.e. the length ratio of the long arm to the short arm) between the rotating rod 502 and the support shaft 503 can be set according to actual needs, such as 2:1, 3:1 or greater, to achieve the required displacement amplification factor.

[0061] Furthermore, the exhaust gas diversion structure 3 includes a draft motor 303, a drive shaft 304, and a fan blade 306. The drive shaft 304 is connected to the output end of the draft motor 303. The fan blade 306 is rotatably mounted on the fixed base 305, and the deflection angle of the fan blade 306 is adjustable. The exhaust gas diversion structure 3 also includes a linkage rod 309 and a sliding ring 307. The sliding ring 307 is slidably sleeved on the drive shaft 304 and connected to the fan blade 306. One end of the linkage rod 309 is rotatably connected to the hinge rod 505, and the other end is slidably connected to the sliding ring 307. It is used to drive the sliding ring 307 to slide along the drive shaft 304 under the drive of the hinge rod 505, so as to adjust the deflection angle of the fan blade 306.

[0062] Specifically, the induced draft motor 303 provides rotational power, driving the fan blades 306 to rotate via the drive shaft 304, generating an induced draft airflow. The blade roots of the fan blades 306 are rotatably mounted on the drive shaft 304, and their deflection angle can be changed. A sliding ring 307 is sleeved on the drive shaft 304, can slide axially, and is connected to the blade roots of each fan blade 306 via a connecting shaft 308. When the sliding ring 307 slides along the drive shaft 304, it drives the blades of the fan blades 306 to rotate around their roots, thereby changing the windward angle of the fan blades 306. One end of the linkage rod 309 is rotatably connected to the hinge rod 505, and the other end is slidably connected to the sliding ring 307. When the hinge rod 505 is driven to move by the rotating rod 502, the linkage rod 309 moves accordingly, pushing or pulling the sliding ring 307 to slide along the drive shaft 304. The change in the deflection angle of the fan blade 306 alters its effective windward area and airflow efficiency, thereby regulating the induced draft while maintaining a constant rotational speed of the induced draft motor 303. For example, when a reduction in induced draft is required, the sliding ring 307 slides in one direction, increasing the deflection angle of the fan blade 306, reducing the windward area, and decreasing the induced draft; conversely, the induced draft increases. This design, through mechanical linkage, achieves continuous and precise adjustment of the induced draft, resulting in a compact structure and rapid response. It should be noted that the number and shape of the fan blade 306 can be designed according to airflow requirements, such as using 3, 4, or more blades, and the blade shape can be airfoil, flat plate, etc. This application does not impose specific limitations in this regard.

[0063] Furthermore, the exhaust gas diversion structure 3 also includes a connecting shell 301 and a supporting mesh plate 302. The connecting shell 301 is disposed inside the air duct assembly 1, the supporting mesh plate 302 is disposed inside the connecting shell 301, and the induced draft motor 303 is mounted on the supporting mesh plate 302.

[0064] Specifically, the connecting housing 301 is a cylindrical or frame structure, fixedly installed inside the duct 101, used to house and support other components of the exhaust gas diversion structure 3. The support mesh plate 302 is a plate-like structure with multiple through holes, fixedly installed inside the connecting housing 301, providing a mounting base for the induced draft motor 303 while allowing airflow. The induced draft motor 303 is fixedly installed on the support mesh plate 302 by bolts or clips. The structural strength of the support mesh plate 302 is sufficient to support the weight of the induced draft motor 303 and vibrations during operation, while its mesh design minimizes obstruction to airflow. This configuration integrates the exhaust gas diversion structure 3 into a modular component, facilitating installation, maintenance, and replacement. Preferably, the support mesh plate 302 can be made of metal or high-strength plastic to ensure its durability.

[0065] This invention also provides a method for recovering and reusing carbon dioxide from food-grade dry ice exhaust gas, applied to the food-grade dry ice exhaust gas carbon dioxide recovery and reuse device described in any of the above technical solutions, comprising the following steps:

[0066] S1. Start the exhaust gas diversion structure 3 to introduce the dry ice exhaust gas generated by the dry ice preparation equipment into the air duct assembly 1;

[0067] S2. The dry ice exhaust flows through the guide plate 103 in the air duct assembly 1. The guide plate 103 adaptively adjusts the opening and closing distance according to the instantaneous flow rate of the dry ice exhaust.

[0068] S3. When the instantaneous flow rate of dry ice exhaust gas exceeds the preset threshold, the guide plate 103 is opened, and the ventilation port 105 between the air duct assembly 1 and the exhaust gas temporary storage mechanism 4 is opened in conjunction, so that part of the dry ice exhaust gas is diverted into the exhaust gas temporary storage mechanism 4 for temporary storage.

[0069] S4. The air pressure in the exhaust gas storage mechanism 4 increases as the amount of dry ice exhaust gas stored increases. This air pressure drives the flow adaptive adjustment component 5 to operate, thereby adjusting the deflection angle of the fan blade 306 of the exhaust gas diversion structure 3 and reducing the induced air volume.

[0070] S5. When the instantaneous flow rate of dry ice exhaust gas drops, the exhaust gas storage mechanism 4 releases the stored dry ice exhaust gas to the air duct assembly 1, and at the same time, the flow adaptive adjustment component 5 reverses its action to increase the air volume of the exhaust gas diversion structure 3.

[0071] S6. The dry ice exhaust gas output from the air duct assembly 1 enters the carbon dioxide liquefaction device 2 and is liquefied into liquid carbon dioxide, and then flows back to the dry ice preparation equipment.

[0072] Specifically, this method fully describes the workflow of the device. In step S1, the induced draft motor 303 starts, driving the fan blades 306 to rotate via the drive shaft 304, generating negative pressure within the air duct assembly 1, actively drawing the carbon dioxide exhaust gas generated by the dry ice preparation equipment during depressurization and forming processes into the air duct 101. In step S2, the drawn-in exhaust gas flows through the guide plate 103, which senses the airflow pressure and automatically adjusts its opening angle. In step S3, when the dry ice preparation equipment is at its peak exhaust period with a large instantaneous flow rate, the guide plate 103 is pushed open to a larger degree by the airflow, and the movable baffle 104 is opened in conjunction with the transmission rod 106, opening the vent 105. Part of the exhaust gas is diverted into the gas storage tank 401 for storage, thereby preventing a large amount of exhaust gas from instantly flooding into the downstream carbon dioxide liquefaction device 2. In step S4, as more gas enters the gas storage tank 401, the gas pressure in the storage chamber increases, pushing the sliding plate 403 to slide and compressing the return spring 404. The displacement of the sliding plate 403 is transmitted through the rotating rod 502, the hinge rod 505, and the linkage rod 309, driving the sliding ring 307 to slide along the drive shaft 304, changing the deflection angle of the fan blade 306, and reducing its frontal area. This effectively reduces the induced draft while keeping the speed of the induced draft motor 303 constant, thus reducing the total amount of exhaust gas drawn in at the source. In step S5, when the exhaust volume of the dry ice preparation equipment decreases, the guide plate 103 gradually closes under its own gravity or the action of the reset mechanism, and the movable baffle 104 also closes the vent 105. Simultaneously, the reset spring 404 in the air storage box 401 pushes the sliding plate 403 to reset, pushing the stored exhaust gas back to the air duct 101 to replenish the intake air. The reset action of the sliding plate 403 reverses the flow adaptive adjustment component 5, restoring the deflection angle of the fan blade 306 and increasing the induced draft. In step S6, the stabilized tail gas flow after buffering and flow regulation finally enters the carbon dioxide liquefaction device 2, where it is liquefied into liquid carbon dioxide under high pressure and low temperature conditions, and then transported back to the front-end process of the dry ice preparation equipment through pipelines to realize the recycling of carbon dioxide.

[0073] Furthermore, in step S4, the flow adaptive adjustment component 5 amplifies the displacement of the sliding plate 403 in the exhaust gas storage mechanism 4 through the lever structure and transmits it to the linkage rod 309 of the exhaust gas diversion structure 3. The linkage rod 309 drives the sliding ring 307 to slide along the drive shaft 304 to change the deflection angle of the fan blade 306.

[0074] Specifically, as described above, the rotating rod 502 and the support shaft 503 form a lever. The lever arm of the support shaft 503 closer to the sliding plate 403 is shorter, while the lever arm farther from the sliding plate 403 is longer. A small displacement of the sliding plate 403, amplified by the lever, results in a larger displacement at the longer arm of the rotating rod 502, thereby driving the hinge rod 505 and the linkage rod 309 to move with a larger stroke. The linkage rod 309 then drives the sliding ring 307 to slide on the drive shaft 304, precisely controlling the deflection angle of the fan blade 306.

[0075] Furthermore, in step S5, the reset spring 404 in the exhaust gas storage mechanism 4 drives the sliding plate 403 to reset, pushing the stored dry ice exhaust gas back to the air duct assembly 1.

[0076] Specifically, when the exhaust gas flow rate drops, the gas pressure inside the gas storage tank 401 decreases. The elastic force of the return spring 404 is greater than the pushing force of the gas pressure on the sliding plate 403, thereby driving the sliding plate 403 to slide towards the gas storage chamber. The reset action of the sliding plate 403 re-pressurizes the dry ice exhaust gas stored in the gas storage chamber back into the duct 101 through the vent 105, supplementing the main airflow. This process not only releases the stored redundant gas and avoids gas waste, but also plays a role in "peak shaving and valley filling," that is, supplementing the intake air during the low exhaust gas flow period, making the airflow entering the carbon dioxide liquefaction device 2 more continuous and stable. The elastic coefficient of the return spring 404 determines the sensitivity and speed of the sliding plate 403's reset, which can be optimized according to the actual operating conditions.

[0077] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0078] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

[0079] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention; the actual structure is not limited thereto. In conclusion, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the spirit of the invention, such designs should fall within the protection scope of the present invention.

Claims

1. A device for recovering and reusing carbon dioxide from food-grade dry ice exhaust gas, characterized in that, include: A duct assembly having a duct for introducing dry ice exhaust gas; A carbon dioxide liquefaction device is connected to the outlet end of the air duct and is used to liquefy the dry ice exhaust gas into liquid carbon dioxide. An exhaust gas diversion structure is installed inside the duct to generate an exhaust airflow. The exhaust gas storage mechanism is connected to the air duct and is used to temporarily store redundant dry ice exhaust gas. And a flow adaptive adjustment component, which is connected to the exhaust gas storage mechanism and the exhaust gas diversion structure respectively, for adjusting the air volume of the exhaust gas diversion structure according to the air pressure change in the exhaust gas storage mechanism, so as to keep the dry ice exhaust gas flow rate entering the carbon dioxide liquefaction device stable.

2. The device for recovering and reusing carbon dioxide from food-grade dry ice exhaust gas according to claim 1, characterized in that, The air duct assembly also includes a guide plate disposed inside the air duct. The guide plate is rotatably disposed, and its opening and closing distance adaptively changes with the instantaneous flow rate of dry ice exhaust gas inside the air duct.

3. The device for recovering and reusing carbon dioxide from food-grade dry ice exhaust gas according to claim 2, characterized in that, The air duct assembly also includes a movable baffle and a transmission rod. The movable baffle is slidably disposed on the side wall of the air duct. One end of the transmission rod is hinged to the guide plate, and the other end is hinged to the movable baffle. The guide plate drives the movable baffle to slide through the transmission rod to control the opening and closing of the ventilation opening between the air duct and the exhaust gas storage mechanism.

4. The device for recovering and reusing carbon dioxide from food-grade dry ice exhaust gas according to claim 1, characterized in that, The exhaust gas storage mechanism includes a gas storage box and a sliding plate slidably disposed in the gas storage box. The sliding plate divides the gas storage box into a gas chamber and a spring chamber. A return spring is provided in the spring chamber. One end of the return spring is connected to the sliding plate, and the other end is connected to the inner wall of the gas storage box.

5. The device for recovering and reusing carbon dioxide from food-grade dry ice exhaust gas according to claim 1, characterized in that, The exhaust gas diversion structure includes an exhaust motor, a drive shaft, and fan blades. The drive shaft is connected to the output end of the exhaust motor, and the fan blades are rotatably mounted on the drive shaft, with the deflection angle of the fan blades being adjustable.

6. The device for recovering and reusing carbon dioxide from food-grade dry ice exhaust gas according to claim 5, characterized in that, The flow adaptive adjustment component includes a rotating rod, a support shaft, and a hinge rod. The middle part of the rotating rod is rotatably sleeved on the support shaft to form a lever structure. The first end of the rotating rod is linked to the sliding plate in the exhaust gas storage mechanism, and the second end of the rotating rod is connected to the exhaust gas diversion structure through the hinge rod.

7. A food-grade dry ice exhaust carbon dioxide recovery and reuse device according to claim 6, characterized in that, The distance between the first end of the rotating rod and the support shaft is greater than the distance between the second end of the rotating rod and the support shaft, so as to form a force-saving lever structure.

8. A food-grade dry ice exhaust carbon dioxide recovery and reuse device according to claim 6, characterized in that, The exhaust gas diversion structure also includes a sliding ring and a linkage rod. The sliding ring is slidably sleeved on the drive shaft and connected to the fan blade. One end of the linkage rod is rotatably connected to the hinge rod, and the other end is slidably connected to the sliding ring. The rotating rod drives the sliding ring to slide along the drive shaft through the hinge rod and the linkage rod to adjust the deflection angle of the fan blade.

9. The food-grade dry ice exhaust carbon dioxide recovery and reuse device according to claim 1, characterized in that, The flow adaptive adjustment component also includes a torsion spring, which is sleeved on the support shaft and connected at both ends to the support shaft and the rotating rod, respectively.

10. A method for recovering and reusing carbon dioxide from food-grade dry ice exhaust, comprising the apparatus described in any one of claims 1 to 9, characterized in that, Includes the following steps: S1. Activate the exhaust gas diversion structure to introduce the dry ice exhaust gas generated by the dry ice preparation equipment into the air duct; S2. Dry ice exhaust gas is transported through a duct to a carbon dioxide liquefaction unit for liquefaction treatment to obtain liquid carbon dioxide. S3. When the instantaneous flow rate of dry ice exhaust gas in the duct exceeds the preset threshold, part of the dry ice exhaust gas is diverted into the exhaust gas storage mechanism for temporary storage. At the same time, the air pressure change in the exhaust gas storage mechanism drives the flow adaptive adjustment component to reduce the air volume of the exhaust gas diversion structure. S4. When the instantaneous flow rate of dry ice exhaust gas in the duct is lower than the preset threshold, the dry ice exhaust gas stored in the exhaust gas storage mechanism is released back into the duct to continue to be transported. At the same time, the flow adaptive adjustment component is reset to increase the air volume of the exhaust gas diversion structure.

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