Supercritical extraction equipment for fish oil processing

Abstract

The invention discloses supercritical extraction equipment for fish oil processing, and relates to the technical field of fish oil production, the supercritical extraction equipment comprises an extraction kettle and a modular gas distribution assembly, the bottom of the extraction kettle is connected with an injection pipe, the modular gas distribution assembly comprises a gas distribution disc arranged at the bottom of the inner wall of the extraction kettle, and a hollow box is fixed at the top of an electromagnetic valve. According to the supercritical extraction equipment for fish oil processing, full contact of supercritical CO2 and crude oil of fish oil can be realized, and stable development of the extraction process is guaranteed; a blocked cavity and a corresponding gas distribution hole can be accurately positioned through pressure difference monitoring, a solenoid valve in a blocked area is closed in a targeted manner, dredging is started, gas distribution and extraction of other non-blocked areas do not need to be interrupted, the overall extraction continuity is maintained, meanwhile, damage to non-blocked parts is avoided, the operation stability of equipment is guaranteed, and the production efficiency is improved. And through the modular disassembly process of the hexagonal cover disc, modules with severely-abraded gas distribution holes can be directly taken down, the whole gas distribution disc does not need to be disassembled, and the maintenance steps are greatly simplified.

Description

Technical Field

[0001] This invention relates to the field of fish oil production technology, specifically to a supercritical extraction device for fish oil processing. Background Technology

[0002] The principle of supercritical carbon dioxide (CO2) extraction of fish oil is to use gaseous CO2 from a CO2 storage tank, which is first compressed to above 7.38 MPa by a high-pressure pump and then heated to above 31.1°C by a heat exchanger to bring it into a supercritical state. The supercritical CO2 fluid enters the extraction vessel and comes into full contact with the crude fish oil. Due to its high solubility, CO2 selectively dissolves the target active ingredients in the fish oil. Its high diffusivity allows it to penetrate deep into the fish oil raw material, accelerating the mass transfer process and improving extraction efficiency. The supercritical CO2 fluid containing the dissolved fish oil components enters the separation vessel, where its supercritical state is broken by depressurization (or heating). After the pressure is reduced, the solubility of CO2 decreases sharply, and the originally dissolved fish oil components precipitate out of the fluid and settle at the bottom of the separation vessel, resulting in a high-purity fish oil product. The separated gaseous CO2 is cooled and liquefied by a condenser and returned to the CO2 storage tank, where it is compressed by a high-pressure pump and heated by a heat exchanger, entering the supercritical state again to participate in the extraction cycle.

[0003] In practical use, existing supercritical fluid extraction equipment for fish oil processing typically requires micropores of 0.5–2 mm to ensure uniform CO2 dispersion. However, the smaller the pore size, the easier it is for the fish oil to be clogged by colloids, waxes, and tiny solid impurities (such as residual protein particles from the raw materials). Existing distributors can only determine whether a blockage has occurred by the overall inlet and outlet pressure difference, and cannot pinpoint the specific location of the blockage. This results in the need to backflush or clean the entire distributor during unblocking, which is inefficient and may damage unblocked pores. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a supercritical extraction device for fish oil processing, which solves the problems mentioned in the background section.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a supercritical extraction device for fish oil processing, comprising an extraction vessel and a modular gas distribution assembly. The bottom of the extraction vessel is connected to an injection pipe. The modular gas distribution assembly includes a gas distribution plate disposed at the bottom of the inner wall of the extraction vessel, with the bottom of the gas distribution plate communicating with the injection pipe. A hexagonal cover plate is arranged one-to-one with a chamber, and the hexagonal cover plates fit snugly together. The gas distribution plate contains uniformly distributed chambers. A hexagonal cover plate is magnetically attracted or engaged at the top of each chamber, and gas distribution holes are uniformly distributed on the surface of the hexagonal cover plate. A telescopic pipe is disposed at the bottom of the inner wall of the chamber, and a solenoid valve is fixed to the top of the telescopic pipe. A hollow box is fixed to the top of the solenoid valve, and a hollow circular plate is magnetically attracted or engaged at the top of the hollow box. Hollow unblocking needles are uniformly distributed on the upper surface of the hollow circular plate. A discharge pipe is disposed at the top of the extraction vessel.

[0006] Furthermore, the bottom of the inner wall of the chamber is designated as the air inlet side, the location of the air distribution hole is designated as the air distribution side, and differential pressure sensors are embedded in the air distribution side and air inlet side of the chamber.

[0007] Furthermore, the hollow unblocking needle is arranged one-to-one with the air distribution hole, and the hollow unblocking needle is located directly below the air distribution hole.

[0008] Furthermore, the hollow box has tube sleeves fixed on both sides of its bottom, and a sliding rod is slidably connected inside the tube sleeve, with the bottom of the sliding rod fixedly connected to the bottom of the inner wall of the cavity.

[0009] Furthermore, the bottom of the hollow unclogging needle is connected to the inside of the hollow box, and an annular filter screen is rotatably connected to the inner wall of the hollow box below the hollow unclogging needle.

[0010] Furthermore, an air distribution plate is fixed to the inner wall of the hollow box below the annular filter, and a micro pump is provided at the bottom of the air distribution plate.

[0011] Furthermore, the output end of the micro pump is connected to a transmission box via a pipe, and the transmission fan blade inside the transmission box is connected to a transmission gear at its center via a shaft.

[0012] Furthermore, the transmission gear is connected to a ring gear on its side, and the ring gear is sleeved and engaged with the bottom outer wall of the ring filter screen.

[0013] Furthermore, there is a gap between the inner side of the gas equalization plate and the inner wall of the hollow box, and the bottom of the inner side of the annular filter screen passes through this gap.

[0014] This invention provides a supercritical fluid extraction device for fish oil processing, which has the following beneficial effects: 1. This supercritical extraction equipment for fish oil processing can achieve full contact between supercritical CO2 and crude fish oil, ensuring stable extraction. Through differential pressure monitoring, it can accurately locate blocked chambers and corresponding gas distribution holes, selectively close the solenoid valves in the blocked areas and start unblocking, without interrupting the gas distribution and extraction in other unblocked areas, maintaining the overall extraction continuity, while avoiding damage to unblocked components, ensuring the stability of equipment operation. Furthermore, through the modular disassembly process of the hexagonal cover plate, modules with severely worn gas distribution holes can be directly removed without disassembling the entire gas distribution plate, greatly simplifying maintenance procedures.

[0015] 2. This supercritical fluid extraction equipment for fish oil processing features a hollow unblocking needle combined with a negative pressure design to efficiently remove blockages from the air distribution holes. The annular filter screen effectively separates impurities from recyclable liquids in the blockages, enabling liquid recycling and reuse and reducing material waste. When the fluid flows through the transmission box, it drives the filter screen to rotate, changing the position of the filter screen and preventing impurities from accumulating and affecting the subsequent blockage treatment effect. Furthermore, the overall structure is adapted to the lifting and lowering movements of the equipment and does not interfere with the normal operation of the equipment. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the internal structure of the extraction vessel in a supercritical extraction device for fish oil processing according to the present invention. Figure 2 This is a schematic diagram of the hexagonal cover plate arrangement structure of a supercritical extraction device for fish oil processing according to the present invention; Figure 3 This is a schematic diagram of the internal structure of a supercritical extraction device for fish oil processing according to the present invention; Figure 4 This is a schematic diagram of the bottom structure of the hollow box in a supercritical extraction device for fish oil processing according to the present invention; Figure 5 This is a schematic diagram of the structure of a supercritical extraction device for fish oil processing after the hollow circular plate and hollow box are separated according to the present invention. Figure 6 This is a schematic diagram of the bottom structure of the gas equalization plate in a supercritical extraction device for fish oil processing according to the present invention.

[0017] In the diagram: 1. Extraction vessel; 2. Injection pipe; 3. Modular gas distribution assembly; 301. Gas distribution plate; 302. Chamber; 303. Hexagonal cover plate; 304. Gas distribution hole; 305. Telescopic pipe; 306. Solenoid valve; 307. Hollow box; 308. Hollow circular plate; 309. Hollow unblocking needle; 310. Tube sleeve; 311. Slide rod; 312. Annular filter screen; 313. Gas distribution plate; 314. Micro pump; 315. Transmission box; 316. Transmission gear; 317. Ring gear; 4. Discharge pipe. Detailed Implementation

[0018] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of the invention.

[0019] like Figures 1-6 As shown, the present invention provides a technical solution: a supercritical extraction device for fish oil processing, comprising an extraction vessel 1 and a modular gas distribution assembly 3. The bottom of the extraction vessel 1 is connected to an injection pipe 2. The modular gas distribution assembly 3 includes a gas distribution plate 301 disposed at the bottom of the inner wall of the extraction vessel 1, and the bottom of the gas distribution plate 301 is connected to the injection pipe 2. The gas distribution plate 301 has uniformly distributed chambers 302 inside, and a hexagonal cover plate 303 is magnetically attracted or engaged at the top of the chambers 302. The surface of the hexagonal cover plate 303 is uniformly distributed with... The air distribution hole 304, the hexagonal cover plate 303 and the chamber 302 are arranged in a one-to-one manner, and the hexagonal cover plates 303 are closely fitted to each other. The bottom of the inner wall of the chamber 302 is provided with a telescopic tube 305, and the top of the telescopic tube 305 is fixed with a solenoid valve 306. The top of the solenoid valve 306 is fixed with a hollow box 307, and the top of the hollow box 307 is magnetically attracted or locked with a hollow circular plate 308. Hollow unblocking needles 309 are evenly distributed on the upper surface of the hollow circular plate 308. The top of the extraction vessel 1 is provided with a discharge pipe 4. The bottom of the inner wall of chamber 302 is set as the air inlet side, and the location of air distribution hole 304 is set as the air distribution side. Differential pressure sensors are embedded on the air distribution side and air inlet side of chamber 302. Hollow unclogging needle 309 is set one-to-one with air distribution hole 304, and the hollow unclogging needle 309 is located directly below air distribution hole 304. Tube sleeves 310 are fixed on both sides of the bottom of hollow box 307, and a sliding rod 311 is slidably connected inside the tube sleeve 310. The bottom of the sliding rod 311 is fixedly connected to the bottom of the inner wall of chamber 302. The specific operation is as follows: First, the pretreated fish oil crude oil to be extracted is injected into the extraction vessel 1 through the injection pipe. After the injection is completed, the injection pipe is closed and the sealing is checked to ensure that the extraction vessel 1 is in a sealed state. Then, gaseous CO2 is extracted from the CO2 storage tank, compressed to the pressure required for supercritical state by a high-pressure pump, and then heated to the temperature required for supercritical state by a heat exchanger, so as to convert it into supercritical CO2 fluid with both high liquid solubility and high gas diffusivity. This supercritical CO2 fluid is continuously injected into the modular extraction vessel through injection pipe 2. The gas distribution plate 301 of the gas distribution assembly 3 then evenly distributes the gas to each chamber 302 of the gas distribution plate 301 and enters the telescopic tube 305 at the bottom of the chamber 302. At this time, the solenoid valve 306 in the chamber 302 is in the open state. The supercritical CO2 fluid passes through the solenoid valve 306, the hollow box 307 and the hollow circular plate 308 in sequence, and finally sprays out evenly from the gas distribution hole 304 on the surface of the hexagonal cover plate 303 at the top of the chamber 302, and fully contacts the fish oil crude oil in the extraction vessel 1 to start the extraction operation of the target component. Each chamber 302 has a set of differential pressure sensors embedded on both the inlet and outlet sides. These sensors monitor the pressure difference in real time and transmit the data to the equipment control system. When the differential pressure sensor for a chamber 302 detects a real-time pressure difference exceeding a preset threshold, it accurately determines that the air distribution hole 304 on the hexagonal cover plate 303 corresponding to that chamber 302 is blocked. The blocked area is immediately located, and the solenoid valve 306 corresponding to that chamber 302 is closed, cutting off the supercritical CO2 supply to that area. Meanwhile, the solenoid valves 306 in other unblocked chambers 302 remain open, and the hexagonal cover plate 303 continues to distribute gas normally, ensuring uninterrupted extraction operations. When the solenoid valve 306 is closed, the supercritical CO2 fluid accumulates in the telescopic tube 305 and generates pressure, pushing the telescopic tube 305 to extend upward, which in turn drives the solenoid valve 306, the hollow box 307, the hollow circular plate 308 and the hollow unblocking needle 309 on the hollow circular plate 308 to rise synchronously. During this process, the sleeves 310 on both sides of the bottom of the hollow box 307 slide smoothly along the outer wall of the slide rod 311, providing precise guidance for the lifting and lowering action, ensuring that the hollow unblocking needle 309 is precisely aligned one-to-one with the air distribution hole 304. Finally, the outer wall of the hollow unblocking needle 309 slides vertically upward against the inner wall of the air distribution hole 304, physically scraping and unblocking the blockage in the air distribution hole 304. After the unblocking process has been running for a period of time, the solenoid valve 306 reopens, allowing the fluid inside the telescopic tube 305 to flow out again, thereby driving the hollow box 307, the hollow circular plate 308, and the hollow unblocking needle 309 to descend and reset synchronously. The hollow unblocking needle 309 exits from the air distribution hole 304. Subsequently, the supercritical CO2 fluid is ejected again through the air distribution hole 304. The differential pressure sensor continuously monitors the pressure difference on both sides. If the pressure difference returns to the preset normal threshold, it indicates that the air distribution hole 304 has been unblocked and the chamber 302 has resumed normal extraction function. During long-term operation of the equipment, historical data from the differential pressure sensors of each chamber 302 can be retrieved. If the differential pressure between the "inlet side and the gas distribution side" of a certain chamber 302 is consistently lower than the preset value, and after ruling out problems such as blockage and abnormal fluid flow, it can be determined that the gas distribution hole 304 on the hexagonal cover plate 303 corresponding to that chamber 302 is severely worn. At the same time, the CO2 bubble morphology in this area can be directly observed through the viewing window of the extraction vessel 1. If the bubble volume is significantly larger than that in other areas, it can be further confirmed that the hexagonal cover plate 303 is a worn module. When replacing the worn hexagonal cover plate 303, first stop the equipment and safely depressurize it to atmospheric pressure. If the hexagonal cover plate 303 and the chamber 302 are magnetically connected, simply hold the edge of the hexagonal cover plate 303 by hand and pull it vertically upwards to remove it. If it is a snap-fit ​​connection, gently insert the plastic pry tool provided with the equipment into the gap between the hexagonal cover plate 303 and the chamber 302, and slowly pry to release the snap-fit. During the operation, avoid using metal tools to prevent scratching the sealing surface of the hexagonal cover plate 303 or the mating surface of the chamber 302, and ensure the sealing of subsequent installations. Based on the above description, the present invention, by introducing supercritical CO2 into the chamber 302 of the modular gas distribution assembly 3 through the injection pipe 2, and then contacting the fish oil in the extraction vessel 1 through the gas distribution hole 304, can ensure that the supercritical fluid and raw materials can fully interact, thus facilitating the efficient extraction of the target components. The process is monitored in real time by the differential pressure sensor of the chamber 302, which can accurately locate the area where the blocked gas distribution hole 304 is located. Then, the solenoid valve 306 of the corresponding chamber 302 is closed and the unblocking process is started. This process does not require interruption of the extraction operation in other unblocked areas, maintaining the continuity of the overall process, and also avoids additional damage to undamaged parts, effectively ensuring the stability of equipment operation. Furthermore, through the modular disassembly process of the hexagonal cover plate 303, the module with severe wear of the air distribution hole 304 can be directly removed without disassembling the entire air distribution plate 301, greatly simplifying the maintenance steps. By aligning the new hexagonal cover plate 303 with the magnetic adsorption of the chamber 302 and the fitting operation of the sealing ring, the module replacement can be completed quickly and the sealing of the chamber 302 can be guaranteed.

[0020] like Figures 1-6 As shown, the bottom of the hollow cleaning needle 309 is connected to the interior of the hollow box 307, and an annular filter 312 is rotatably connected to the inner wall of the hollow box 307 below the hollow cleaning needle 309; an air distribution plate 313 is fixed to the inner wall of the hollow box 307 below the annular filter 312, and a micro pump 314 is provided at the bottom of the air distribution plate 313; the output end of the micro pump 314 is connected to a transmission box 315 through a pipe, and a transmission fan blade inside the transmission box 315 is connected to a transmission gear 316 at its center through a shaft; an annular gear 317 is meshed with the side of the transmission gear 316, and the annular gear 317 is sleeved and meshed with the bottom outer wall of the annular filter 312, and the annular gear 317 is rotatably connected to the bottom of the inner wall of the hollow box 307; there is a gap between the inner side of the air distribution plate 313 and the inner wall of the hollow box 307, and the bottom of the inner side of the annular filter 312 passes through the gap; The specific operation is as follows: When the differential pressure sensor in chamber 302 detects that the air distribution hole 304 is blocked, the telescopic tube 305 extends and drives the hollow box 307 to rise vertically. At this time, the sleeve 310 slides smoothly along the outer wall of the slide rod 311, providing precise guidance for the lifting and lowering of the hollow box 307, ensuring that the hollow unblocking needle 309 on the hollow circular plate 308 is accurately aligned with the air distribution hole 304 and slides along the inner wall of the air distribution hole 304. Due to the hollow structure design of the hollow unblocking needle 309, the blockage will enter its internal channel during the sliding process. At the same time, the micro pump 314 at the bottom of the air equalization plate 313 in the hollow box 307 starts synchronously. The negative air pressure generated is evenly diffused through the air equalization holes of the air equalization plate 313 to the bottom of each hollow unblocking needle 309, forming a stable and uniform adsorption force, which further thoroughly sucks the stubborn blockage attached to the inner wall of the air distribution hole 304 into the hollow unblocking needle 309, improving the unblocking cleanliness. Because the blockage contains oil and other liquid components, this liquid naturally slides down the internal channel of the hollow unblocking needle 309, passes through the annular filter 312 rotatably connected to the inner wall of the hollow box 307, and the annular filter 312 accurately intercepts solid impurities in the blockage, leaving them on the filter surface or inside the hollow unblocking needle 309, while the separated liquid falls onto the surface of the gas equalization plate 313; under the negative pressure generated by the micro pump 314, this recyclable liquid flows into the transmission box 315 through the pipeline, and then is discharged into the extraction vessel 1 through the corrugated pipe connected to the end of the transmission box 315 for recycling and reuse. The expansion and contraction characteristics of the corrugated pipe can be fully adapted to the lifting and lowering movement of the hollow box 307, avoiding damage to the pipeline by pulling and ensuring a smooth liquid recovery process; When the liquid flows through the transmission box 315, it drives the internal transmission fan blades to rotate. The transmission fan blades drive the transmission gear 316 to rotate synchronously through the central shaft. The transmission gear 316 meshes with the ring gear 317 fixed on the bottom outer wall of the ring filter screen 312, thereby driving the ring filter screen 312 to rotate smoothly along the inner wall of the hollow box 307. This allows the clean area of ​​the ring filter screen 312 that has not trapped impurities to continue rotating to below the hollow unblocking needle 309, effectively preventing solid impurities from accumulating in the same position for a long time. This ensures that the negative pressure conduction is not obstructed during the subsequent removal of blockages, guaranteeing the continuity and effectiveness of the unblocking operation. Based on the equipment operating load and the impurity content of the raw materials, the annular filter 312 should be cleaned regularly after every 10-15 batches of extraction or when the differential pressure sensor detects that the frequency of differential pressure fluctuation in a certain chamber 302 increases by more than 30%. If the raw materials contain high levels of colloids and waxes, the cleaning frequency can be shortened to once every 5-8 batches to avoid long-term accumulation of impurities affecting the unblocking efficiency and equipment lifespan. The cleaning process for the annular filter screen 312 is as follows: Remove the hexagonal cover plate 303 and disassemble the hollow circular plate 308. Use an L-shaped plastic hook to gently hook the edge of the filter screen and slowly lift it upwards to separate the bottom of the annular filter screen 312 from the annular gear 317 on its outer wall. After removing the annular filter screen 312, a new filter screen can be replaced to mesh with the inner wall of the annular gear 317. For the removed annular filter screen 312, use a soft nylon brush to gently brush the surface of the annular filter screen 312 clockwise, focusing on cleaning solid impurities in the filter screen pores, such as protein particles and wax clumps. You can use a hook to gently pick out stubborn impurities that block the pores. When replacing the filter, use a soft brush to gently clean the residual impurities on the inner wall of the hollow box 307 and the surface of the air distribution plate 313, and focus on cleaning the air distribution holes of the air distribution plate 313 to ensure smooth airflow. Based on the above description, this invention utilizes the process of the hollow unblocking needle 309 sliding vertically upwards towards the air distribution hole 304, combined with the operation of the micro pump 314 generating negative pressure and evenly dispersing it through the air distribution plate 313. This process can efficiently adsorb blockages in the air distribution hole 304, improving the thoroughness of unblocking. The blockages fall into the annular filter screen 312 through the hollow unblocking needle 309, where the annular filter screen 312 separates impurities from recyclable liquid. The liquid is then returned to the extraction vessel 1 through a corrugated pipe, achieving material recycling and reducing waste. Furthermore, the recyclable liquid flows through the transmission box 315, driving the transmission fan blades to rotate, which in turn drives the annular filter screen 312 to rotate through the transmission gear 316 meshing with the annular gear 317. This process achieves filter screen position changes, preventing impurity accumulation from affecting subsequent unblocking effects. The guide process of the sleeve 310 sliding along the slide rod 311 ensures that the hollow box 307 rises and falls smoothly without interfering with the normal operation of the equipment, further improving the practicality and operational efficiency of the equipment.

[0021] In summary, when using this supercritical fish oil extraction equipment, the crude fish oil to be extracted is first injected into the extraction vessel 1 through the injection pipe. Then, gaseous CO2 from the CO2 storage tank is first compressed to above 7.38 MPa by a high-pressure pump, and then heated to above 31.1°C by a heat exchanger to bring it into a supercritical state. The supercritical CO2 fluid is injected into the gas distribution plate 301 through the injection pipe 2, and then evenly enters the telescopic pipes 305 of each chamber 302. At this time, the solenoid valve 306 is opened, allowing the supercritical CO2 fluid to pass through the hollow parts of the hollow box 307 and the hollow circular plate 308, and then be injected into the extraction vessel 1 from the inside of the chamber 302 through the gas distribution holes 304 on the surface of the hexagonal cover plate 303, where it comes into contact with the crude oil inside and performs the extraction operation. The differential pressure sensor monitors the pressure difference between the air distribution side and the air intake side in real time. Each chamber 302 is equipped with a set of differential pressure sensors. When the real-time pressure difference is greater than the threshold, the air distribution hole 304 at the location of the differential pressure sensor corresponding to the pressure difference value on the surface, i.e., the location of the chamber 302, becomes blocked. Based on the position of the hexagonal cover plate 303, the corresponding solenoid valve 306 is controlled to close. At this time, the fluid no longer passes through the hexagonal cover plate 303 where the blockage is located, while the hexagonal cover plates 303 at other positions can still perform uniform air distribution. At the same time, the fluid gathers inside the telescopic tube 305 and stretches because the solenoid valve 306 is closed. This causes the hollow circular plate 308 and the hollow unblocking needle 309 on its surface to slide vertically along the outer wall of the slide rod 311 through the sleeve 310 and rise vertically. This causes the hollow unblocking needle 309 to slide upwards along the inner wall of the air distribution hole 304 on its outer wall, thereby unblocking the air distribution hole 304. When the differential pressure sensor in chamber 302 detects that the air distribution hole 304 is blocked, the telescopic tube 305 extends and drives the hollow box 307 to rise vertically. At this time, the sleeve 310 slides smoothly along the outer wall of the slide rod 311, providing precise guidance for the lifting and lowering of the hollow box 307. This ensures that the hollow unblocking needles 309 on the hollow circular plate 308 are precisely aligned with the air distribution hole 304 and slide along the inner wall of the air distribution hole 304. Due to the hollow structure design of the hollow unblocking needles 309, the blockage will enter its internal channel during the sliding process. At the same time, the micro pump 314 at the bottom of the air equalization plate 313 in the hollow box 307 starts synchronously. The negative air pressure generated is evenly diffused through the air equalization holes of the air equalization plate 313 to the area below each hollow unblocking needle 309, forming a stable and uniform adsorption force. This further thoroughly sucks the stubborn blockages attached to the inner wall of the air distribution hole 304 into the hollow unblocking needles 309, improving the cleanliness of the unblocking process. Because the blockage contains oil and other liquid components, this liquid naturally slides down the internal channel of the hollow unblocking needle 309, passes through the annular filter 312 rotatably connected to the inner wall of the hollow box 307, and the annular filter 312 accurately intercepts solid impurities in the blockage, leaving them on the filter surface or inside the hollow unblocking needle 309, while the separated liquid falls onto the surface of the gas equalization plate 313; under the negative pressure generated by the micro pump 314, this recyclable liquid flows into the transmission box 315 through the pipeline, and then is discharged into the extraction vessel 1 through the corrugated pipe connected to the end of the transmission box 315 for recycling and reuse. The expansion and contraction characteristics of the corrugated pipe can be fully adapted to the lifting and lowering movement of the hollow box 307, avoiding damage to the pipeline by pulling and ensuring a smooth liquid recovery process; When the liquid flows through the transmission box 315, it drives the internal transmission fan blades to rotate. The transmission fan blades drive the transmission gear 316 to rotate synchronously through the central shaft. The transmission gear 316 meshes with the ring gear 317 fixed to the bottom outer wall of the ring filter 312, thereby driving the ring filter 312 to rotate smoothly along the inner wall of the hollow box 307. This allows the clean area of ​​the ring filter 312 that has not trapped impurities to continue rotating to below the hollow unblocking needle 309, effectively preventing solid impurities from accumulating in the same position for a long time. This ensures that the negative pressure conduction is not obstructed during the subsequent removal of blockages, guaranteeing the continuity and effectiveness of the unblocking operation.

[0022] The embodiments of the present invention are given for illustrative and descriptive purposes only, and are not intended to be exhaustive or to limit the invention to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described in order to better illustrate the principles and practical application of the invention, and to enable those skilled in the art to understand the invention and to design various embodiments with various modifications suitable for a particular purpose.

Claims

1. A supercritical extraction apparatus for fish oil processing, comprising an extraction vessel (1) and a modular gas distribution assembly (3), characterized in that: The bottom of the extraction vessel (1) is connected to an injection pipe (2). The modular gas distribution assembly (3) includes a gas distribution plate (301) disposed at the bottom of the inner wall of the extraction vessel (1), and the bottom of the gas distribution plate (301) is connected to the injection pipe (2). The gas distribution plate (301) is uniformly provided with chambers (302) inside. The top of the chamber (302) is magnetically attracted or locked with a hexagonal cover plate (303), and the surface of the hexagonal cover plate (303) is uniformly provided with gas distribution holes (304). The hexagonal cover plate (303) and the chamber (302) are connected to each other. 2) The hexagonal cover plates (303) are arranged in a one-to-one configuration and are fitted together. The bottom of the inner wall of the chamber (302) is provided with a telescopic tube (305) and a solenoid valve (306) is fixed on the top of the telescopic tube (305). A hollow box (307) is fixed on the top of the solenoid valve (306) and a hollow circular plate (308) is magnetically attracted or locked on the top of the hollow box (307). Hollow unblocking needles (309) are evenly distributed on the upper surface of the hollow circular plate (308). A discharge pipe (4) is provided on the top of the extraction vessel (1).

2. The supercritical fluid extraction equipment for fish oil processing according to claim 1, characterized in that: The bottom of the inner wall of the chamber (302) is set as the air inlet side, the location of the air distribution hole (304) is set as the air distribution side, and differential pressure sensors are embedded in the air distribution side and air inlet side of the chamber (302).

3. The supercritical fluid extraction equipment for fish oil processing according to claim 1, characterized in that: The hollow unblocking needle (309) and the air distribution hole (304) are arranged one-to-one, and the hollow unblocking needle (309) is located directly below the air distribution hole (304).

4. The supercritical fluid extraction equipment for fish oil processing according to claim 1, characterized in that: The hollow box (307) has a tube sleeve (310) fixed on both sides of the bottom, and a slide rod (311) is slidably connected inside the tube sleeve (310). The bottom of the slide rod (311) is fixedly connected to the bottom of the inner wall of the chamber (302).

5. The supercritical fluid extraction equipment for fish oil processing according to claim 1, characterized in that: The bottom of the hollow unclogging needle (309) is connected to the inside of the hollow box (307), and an annular filter screen (312) is rotatably connected to the inner wall of the hollow box (307) below the hollow unclogging needle (309).

6. The supercritical fluid extraction equipment for fish oil processing according to claim 5, characterized in that: The hollow box (307) has an air distribution plate (313) fixed on its inner wall below the annular filter (312), and a micro pump (314) is provided at the bottom of the air distribution plate (313).

7. The supercritical fluid extraction equipment for fish oil processing according to claim 6, characterized in that: The output end of the micro pump (314) is connected to the transmission box (315) through a pipe, and the transmission fan blade inside the transmission box (315) is connected to the transmission gear (316) through a shaft at its center.

8. The supercritical fluid extraction equipment for fish oil processing according to claim 7, characterized in that: The transmission gear (316) is connected to a ring gear (317) on its side, and the ring gear (317) is sleeved and engaged with the bottom outer wall of the ring filter (312).

9. The supercritical fluid extraction equipment for fish oil processing according to claim 6, characterized in that: There is a gap between the inner side of the gas equalization plate (313) and the inner wall of the hollow box (307), and the bottom of the inner side of the annular filter (312) passes through the gap.

Images