Multistage countercurrent solid-liquid separation device and process for extracting polysaccharide from edible fungi

Abstract

The invention relates to the technical field of solid-liquid separation and extraction, and discloses a multi-stage countercurrent solid-liquid separation device and process for extracting edible mushroom polysaccharide, and the process comprises the following steps: continuously and quantitatively adding heat-sensitive edible mushrooms into the top of a first-stage extraction tower; pumping a separation solvent from the bottom of the last-stage extraction tower, and enabling the solvent to sequentially flow through at least three series-connected extraction towers opposite to the flow direction of the edible mushrooms; under the constant temperature condition of 50-60 DEG C, multi-stage countercurrent contact separation is carried out in each stage of extraction tower, so that polysaccharide in the edible mushrooms is fully transferred into a solvent, and polysaccharide-rich extraction liquid is obtained from the first stage of extraction tower. According to the invention, through whole-course refined temperature control of constant temperature of the extraction tower jacket, a water-cooling jacket of the filter pressing unit and low-temperature vacuum concentration, the whole extraction process is ensured to be carried out in a set low-temperature range, degradation or inactivation of a heat-sensitive target component caused by local overheating is effectively avoided, and protection of the heat-sensitive component is improved.

Description

Technical Field

[0001] This invention relates to the field of solid-liquid separation technology, specifically to a multi-stage countercurrent solid-liquid separation device and process for extracting polysaccharides from edible fungi. Background Technology

[0002] Solvent extraction is a key unit operation in the fields of chemical, pharmaceutical, food, and natural product extraction for separating target components from edible fungi. It mainly includes solid-liquid extraction methods, such as maceration and Soxhlet extraction. These are mostly batch operations and generally suffer from disadvantages such as low extraction efficiency, large solvent consumption, long production cycle, and high labor intensity. For heat-sensitive edible fungi, such as natural products containing proteins, enzymes, and polysaccharides, traditional separation methods are still difficult to precisely control the process temperature. Local overheating can easily lead to denaturation, degradation, or inactivation of target components. To improve efficiency, multi-stage countercurrent extraction has been proposed and applied in some fields. However, in practical applications, the following problems still arise.

[0003] For example, the equipment has low integration, and the processes of extraction, solid-liquid separation, and solvent recovery are not well connected, making it difficult to achieve continuous operation. Furthermore, the process temperature is difficult to control, especially for heat-sensitive target components, where local overheating can easily lead to degradation and inactivation. During continuous operation, solid materials are prone to clogging at the feed inlet or filter interface, affecting stable operation. Therefore, there is an urgent need to develop an integrated solid-liquid extraction process and device that can achieve continuous, stable, and efficient operation, control the temperature, and realize a closed-loop solvent circulation. Summary of the Invention

[0004] To address the technical problems in existing technologies, such as low solid-liquid separation efficiency, poor process temperature control accuracy, easy denaturation and agglomeration of solid components, poor operational continuity, and high solvent consumption in heat-sensitive edible fungi, this invention provides a multi-stage countercurrent solid-liquid continuous separation process and its integrated device that features high separation efficiency, avoids denaturation of solid components, can operate continuously and stably, and allows for solvent recycling.

[0005] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows: In a first aspect, a multi-stage countercurrent solid-liquid separation process for extracting polysaccharides from edible fungi includes the following steps: The heat-sensitive edible fungi are continuously and quantitatively added to the top of the first-stage extraction tower; the separation solvent is pumped in from the bottom of the last-stage extraction tower, so that the solvent flows against the flow direction of the edible fungi and passes through at least three extraction towers connected in series. Under constant temperature conditions of 50 to 60 degrees Celsius, multi-stage countercurrent contact separation is carried out in each extraction tower to fully transfer polysaccharides from edible fungi into the solvent, and extracts rich in polysaccharides are obtained from the first extraction tower. The solid residue discharged from the final extraction tower is filtered by pressure. The pressure filtration process is carried out under a temperature control of 50 to 60 degrees Celsius to separate the residual polysaccharide filtrate. The extract and the filtered liquid are combined into a mixed extract, which is then concentrated at 40 to 50 degrees Celsius under vacuum to obtain a polysaccharide concentrate. The evaporated solvent is then condensed and recovered to achieve a closed-loop cycle.

[0006] A multi-stage countercurrent solid-liquid separation device, applied in the aforementioned multi-stage countercurrent solid-liquid separation process for extracting polysaccharides from edible fungi, includes a housing, with a mounting platform on the top of the housing, and further includes: A multi-stage countercurrent extraction mechanism is installed on the platform and includes at least three extraction towers connected in series along the material flow direction and a solvent tank for storing solvent; adjacent extraction towers are connected in series through pipes, and the outer wall of each extraction tower is provided with an insulation jacket connected to an external constant temperature circulating water bath system. The feeding section is connected to the first-stage extraction tower of the multi-stage countercurrent extraction mechanism and is used to quantitatively deliver edible fungi into the system. The low-temperature pressure filtration section is connected to the slurry outlet of the last stage extraction tower of the multi-stage countercurrent extraction mechanism and is used to perform low-temperature pressure filtration on the extraction residue. The low-temperature concentration section is connected to the filtrate outlet of the low-temperature filtration section and is used to concentrate the mixed extract at low temperature and recover the solvent. A pumping control assembly, connected to the solvent tank and the final extraction tower, is used to pump the solvent into the system and drive it to flow countercurrently.

[0007] Furthermore, the feeding section includes a dry powder cylinder, a screw conveyor and a vibrating element disposed inside the dry powder cylinder; the screw conveyor is connected to the vibrating element, and the vibrating element is disposed below the sieve plate at the top of the extraction tower.

[0008] Furthermore, the screw conveyor is controlled by a processor, which adjusts the speed of the screw conveyor to control the feed rate based on the sensor signal of the material in the dry powder cylinder.

[0009] Furthermore, the low-temperature pressure filtration section includes a sealed cylinder and a double cooling seat disposed therein; the double cooling seat is a jacketed structure used to introduce circulating cooling medium to control the pressure filtration temperature; the sealed cylinder is provided with a filter cylinder and a scraper component that cooperates with it.

[0010] Furthermore, the scraping component includes a scraper that adheres to the inner wall of the filter cartridge, the scraper being preloaded by a spring for scraping off residue from the inner wall of the filter cartridge.

[0011] Furthermore, the low-temperature concentration section includes an evaporator, a funnel for introducing the extract into the evaporator, and a condensation recovery unit for condensing the evaporated solvent and returning it to the solvent tank.

[0012] Furthermore, the evaporator is slidably mounted on a slide rail, and the condensation recovery unit is connected to the solvent tank via a pipe. Furthermore, a cover plate is hinged to the outside of the box body; As a preferred application of the above-mentioned technical solution of the present invention, the process and apparatus are particularly suitable for extracting heat-sensitive edible fungi polysaccharides from dried edible fungi powder.

[0013] The above-described solution of the present invention has at least the following beneficial effects: 1. By adopting a multi-stage countercurrent extraction method, a stable concentration gradient was established, which maximized the mass transfer driving force, making the extraction of polysaccharides more thorough and significantly improving the yield, resulting in high extraction efficiency and yield.

[0014] 2. The countercurrent process improves solvent utilization and, together with the integrated condensation and recovery system, achieves closed-loop solvent recycling, reducing solvent consumption and production costs. It is environmentally friendly and features low solvent consumption and recyclability.

[0015] 3. Through precise temperature control throughout the entire process, including constant temperature in the extraction tower jacket, water-cooled jacket in the pressure filtration unit, and low-temperature vacuum concentration, the entire extraction process is ensured to be carried out within the set low temperature range. This effectively avoids degradation or inactivation of heat-sensitive target components due to local overheating, thus enhancing the protection of heat-sensitive components.

[0016] 4. The vibration design of the feeding section effectively prevents solid material blockage; the continuous scraper mechanism of the filter press avoids filter hole blockage, ensuring continuous and efficient solid-liquid separation; and with the close connection of each unit, continuous and automated operation from feeding, extraction, filter press to concentration is realized, with stable and reliable operation. Attached Figure Description

[0017] The invention will now be further described with reference to the accompanying drawings.

[0018] Figure 1 This is a schematic diagram of the overall structure provided for an embodiment of the present invention; Figure 2 An exploded view of the structure of the extraction tower, dry powder cylinder, solvent tank, and sealed cylinder assembly is provided for embodiments of the present invention. Figure 3 An exploded perspective view of the combination of processor, rotating shaft and screw conveyor is provided for embodiments of the present invention; Figure 4 This is provided by the embodiments of the present invention. Figure 3 Enlarged schematic diagram of the local structure at point C; Figure 5 This is an exploded view of the assembly structure of the shell, peristaltic pump, peristaltic tube, first conduit, and second conduit provided in an embodiment of the present invention; Figure 6 This is a cross-sectional schematic diagram of the internal structure of the sealing cylinder provided in an embodiment of the present invention; Figure 7 This is provided by the embodiments of the present invention. Figure 6 Enlarged schematic diagram of a local structure at point A; Figure 8 This is an exploded view of the support platform, collection box, and drive slider structure provided in an embodiment of the present invention.

[0019] In the diagram: 1. Box body; 2. Cover plate; 3. Placement platform; 4. Extraction tower; 5. Solvent tank; 7. Through pipe; 8. Sealing cylinder; 9. Double cooling seat; 10. Main rod; 11. Sieve plate; 12. Dry powder cylinder; 13. Thin tube; 14. Insert strip; 15. Assembly box; 16. Assembly shell; 17. Fixing key; 18. Peristaltic pump; 19. Peristaltic tube; 20. Processor; 21. Rotating shaft; 22. Screw conveyor; 23. First 24. Second shell; 25. Vibrator; 26. Pipe; 27. Vibrating bar; 28. Striking ball; 29. ​​First conduit; 30. Second conduit; 31. Spiral rotating blade; 32. Fine rotating blade; 33. Filter cylinder; 34. Scraper; 35. Spring; 36. Support platform; 37. Collection box; 38. Evaporator; 39. Slide rail; 40. Insertion pipe; 41. Drive slider; 42. Insertion tube; 43. Funnel. Detailed Implementation

[0020] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the structure and process of the universal solid-liquid continuous extraction device of this invention will be described in detail below with reference to the accompanying drawings. Those skilled in the art will understand that the technical solutions provided by this invention have wide applicability. For ease of understanding, the extraction of polysaccharides from dried edible fungi powder is used here as a specific and non-limiting application example to illustrate its working process and effects.

[0022] like Figures 1 to 8 As shown, the present invention provides a multi-stage countercurrent solid-liquid separation process for extracting polysaccharides from edible fungi, comprising the following steps: The heat-sensitive edible fungi are continuously and quantitatively added to the top of the first-stage extraction tower; the separation solvent is pumped in from the bottom of the last-stage extraction tower, so that the solvent flows against the flow direction of the edible fungi and passes through at least three extraction towers in series. Under constant temperature conditions of 50 to 60 degrees Celsius, multi-stage countercurrent contact separation is carried out in each extraction tower to fully transfer polysaccharides from edible fungi into the solvent, and extracts rich in polysaccharides are obtained from the first extraction tower. The solid residue discharged from the final extraction tower is filtered by pressure. The pressure filtration process is carried out under a controlled temperature of 50 to 60 degrees Celsius to separate the residual polysaccharide filtrate. The extract and the filtrate were combined into a mixed extract, which was then concentrated at 40 to 50 degrees Celsius under vacuum to obtain a polysaccharide concentrate. The evaporated solvent was then condensed and recovered to achieve a closed-loop cycle.

[0023] like Figures 2 to 8 As shown, a multi-stage countercurrent solid-liquid separation device is used in the above-mentioned multi-stage countercurrent solid-liquid separation process for extracting polysaccharides from edible fungi. It includes a housing 1, with a mounting platform 3 on the top of the housing 1, and further includes: The multi-stage countercurrent extraction mechanism is set on the placement platform 3 and includes at least three extraction towers 4 connected in series along the material flow direction and a solvent tank 5 for storing solvent; adjacent extraction towers 4 are connected in series through pipes 7, and the outer wall of each extraction tower 4 is provided with an insulation jacket connected to an external constant temperature circulating water bath system. The feeding section is connected to the first-stage extraction tower of the multi-stage countercurrent extraction mechanism and is used to quantitatively deliver edible fungi into the system. The low-temperature pressure filtration section is connected to the slurry outlet of the last stage extraction tower of the multi-stage countercurrent extraction mechanism, and is used to perform low-temperature pressure filtration on the extraction residue at a temperature of fifty to sixty degrees Celsius. The low-temperature concentration section is connected to the clear liquid outlet of the low-temperature pressure filtration section. It is used to concentrate the mixture of the separated liquid produced by multi-stage countercurrent extraction and the residual liquid produced by low-temperature pressure filtration at a low temperature and recover the solvent. The temperature is 40 to 50 degrees Celsius. The pumping control assembly, connected to solvent tank 5 and final extraction tower 4, is used to pump solvent into the system and drive its countercurrent delivery. The pumping control assembly includes a peristaltic pump, an automatic control valve group, and a PID controller. The automatic control valve group includes an electric regulating valve connected in series with the solvent delivery pipeline and a pressure sensor installed at the solvent inlet at the bottom of the final extraction tower 4. The PID controller is electrically connected to the pressure sensor and the electric regulating valve respectively. By comparing the measured pressure value with the set value, it dynamically adjusts the opening of the electric regulating valve to achieve constant and stable controllable pressure for the countercurrent delivery of solvent.

[0024] Specifically, the dry powder cylinder 12 is used to drop edible fungi from top to bottom into the interior of the extraction tower 4; there are three extraction towers 4, which are designated as the first extraction tower, second extraction tower, and third extraction tower from left to right, and are connected to each other by a connecting pipe 7, and are also connected to a peristaltic pump 18 via a peristaltic pipe 19. A solvent tank 5 is used to store and supply extraction solvent to the final extraction tower, and a pumping control component is used to drive the solvent from the bottom of the third extraction tower and transport it against the material flow direction; the pumping control component is used to stably drive the solvent to flow against the flow direction, and it does not... Including only the peristaltic pump 18, it also includes an automatic control valve assembly, which consists of an electric regulating valve and a pressure sensor installed at the bottom inlet of the final extraction tower. The system uses a PID controller to compare the measured pressure value with the set value and dynamically adjust the opening of the electric regulating valve to ensure a constant feed pressure of the countercurrent solvent and maintain a stable fluid environment inside the extraction tower. The insert 42 is used for upward pouring to facilitate the extraction of edible fungi polysaccharides. The automatic control valve assembly is located inside the dry powder cylinder 12 and can control the temperature at fifty to sixty degrees Celsius to avoid thermal degradation of the target components. In practical application, the equipment generates two main material flows during operation. Edible mushroom powder is quantitatively added to the first-stage extraction tower through the feeding section and moves downwards step by step by gravity. At the same time, the extraction solvent is pumped from solvent tank 5 to the bottom of the final extraction tower via the pump control component, flowing upwards step by step against the flow direction of the edible mushroom powder. During this countercurrent contact process, the polysaccharides in the edible mushroom powder continuously dissolve into the solvent. Finally, the polysaccharide-rich extract is discharged from one side outlet of the first-stage extraction tower, while the solid residue after multi-stage extraction is discharged from the bottom of the final extraction tower and enters the low-temperature pressure filtration section. In the pressure filtration section, the solid residue is mechanically squeezed, and the separated filtrate is combined with the aforementioned extract and sent together to the low-temperature concentration section. In the concentration section, the mixed extract is concentrated under low-temperature vacuum to obtain concentrated extract. The evaporated solvent is condensed and recovered and returned to solvent tank 5 for recycling.

[0025] like Figures 2 to 4 The feeding section includes a dry powder cylinder 12, a screw conveyor 22 disposed inside the dry powder cylinder 12, a vibrating element, and a first motor; the screw conveyor 22 is connected to the vibrating element, which is disposed below the sieve plate 11 at the top of the extraction tower 4; The screw conveyor 22 is controlled by a processor 20, which adjusts the speed of the screw conveyor 22 to control the feed rate based on the sensor signal of the material in the dry powder cylinder 12.

[0026] Dry powder cylinder 12 is fixedly installed on the top of extraction tower 4; The processor 20 is located on the inner wall of the dry powder cylinder 12. It is equipped with a micro sensor and an induction switch. The micro sensor is used to sense the edible fungus dry powder. After sensing the edible fungus dry powder, the induction switch controls the first motor to start. The first motor is located inside the dry powder cylinder 12 and is connected to the rotating shaft 21 to provide driving force for the rotating shaft 21. The rotating shaft 21 is rotatably positioned at the center of the processor 20; The screw conveyor 22 is installed on the inner wall of the dry powder cylinder 12 and is controlled by the processor 20. It is used to quantitatively convey edible fungus dry powder. The processor 20 adjusts the conveying amount by controlling the rotation speed of the rotating shaft 21. The first housing 23 is disposed inside the screw conveyor 22, and the inner wall of the first housing 23 is provided with a second housing 24; The vibrating components include a vibrator 25, a pipe 26, a vibrating strip 27, and a striking ball 28; Vibrator 25 is disposed on the inner wall of the second housing 24; Pipe 26 is located at the bottom end of vibrator 25; Vibration bar 27 is positioned above vibrator 25; The striking ball 28 is located at one end of the vibrating strip 27; The vibrator 25 drives the vibrating bar 27 and the striking ball 28 to vibrate, which is used to prevent the dried edible fungus powder from accumulating and clogging in the pipe 26 and the sieve plate 11, and works with the screw conveyor 22 to achieve quantitative feeding.

[0027] Specifically, the processor 20 is equipped with a photoelectric sensor and an induction switch. The photoelectric sensor is installed at a preset height on the inner wall of the dry powder cylinder 12. When it detects edible fungus powder, it drives the induction switch, which in turn starts the motor on the rotating shaft 21 to detect the presence of material. When the sensor detects that the material is below a preset threshold, the induction switch is triggered and sends a signal to the processor 20. The processor 20 has a preset program built in. Based on the received signal and the preset feed rate model, the algorithm program outputs a corresponding control signal to the first motor, thereby precisely adjusting the rotation speed of the rotating shaft 21 to achieve continuous, stable, and quantitative conveying of edible fungus powder. The processor 20 is also equipped with a touch screen or communication interface for manually setting the target feed amount or receiving control commands from the host computer. The screw conveyor 22 is hollow inside for storing edible fungus powder. The first shell 23 and the second shell 24 are used to transfer the edible fungus powder downward into the first extraction tower. The vibrating strip 27 facilitates the vibration of the edible fungus powder inside, promoting its use. The vibrator 25 is used to drive... The ball 28 is struck to accelerate its descent; the junction between the first shell 23 and the second shell 24 is arc-shaped, where the junction refers to the connection surface between the inner and outer walls of the first shell and the second shell, facilitating the falling of the dried mushroom powder below; the solvent tank 5 is located next to the third extraction tower; the automatic control valve assembly is located on the lower side of the third extraction tower, near the bottom inlet, and is a close-fitting accessory of the tower assembly. The automatic control valve assembly includes at least one electric regulating valve and one pressure sensor. The pressure sensor is installed on the outlet of the peristaltic pump 18 or the solvent inlet pipe 7 at the bottom of the third extraction tower 4, and is used to monitor the delivery pressure or flow rate of the solvent in real time. The electric regulating valve is connected in series in the short pipe between the solvent tank 5 and the peristaltic pump 18. The automatic control valve assembly is electrically connected to a central controller. The central controller receives the feedback signal from the sensor and compares it with the preset pressure or flow rate setpoint. It outputs a control signal through a closed-loop control algorithm to adjust the opening of the electric regulating valve, thereby achieving precise and automatic control of the flow rate and pressure of the solvent countercurrent delivery, ensuring stable contact between the liquid and solid phases in the extraction tower.

[0028] In practical applications, edible mushroom powder enters from the top of the first extraction tower via a screw feeder and moves slowly downwards under gravity. Fresh extraction solvent flows out from solvent tank 5, is pressurized by peristaltic pump 18, and regulated by an external automatic control valve group to complete the feeding. During liquid feeding, the solvent flows upwards from the bottom of the third extraction tower, opposite to the flow direction of the edible mushroom powder, thus forming countercurrent. Upon entering the tower, the edible mushroom powder encounters a concentrated solvent that has already undergone one round of extraction and is rich in polysaccharides. At this point, the polysaccharide concentration in the edible mushroom powder is high, and the concentrated solvent can quickly extract the polysaccharides. When entering the second extraction tower, it encounters a medium-concentration solvent, further... The remaining polysaccharides are extracted. Finally, the powder enters the third extraction tower, where it encounters fresh solvent that has just entered the system and contains almost no polysaccharides. At this point, the polysaccharide concentration in the dried edible fungus powder has decreased, and the fresh solvent can fully extract the remaining polysaccharides, avoiding waste. After triple countercurrent extraction, the dried edible fungus powder becomes a solid residue coated with residual polysaccharides and solvent. It is a mixture of solid particles and polysaccharide solution, which flows continuously from the bottom of the third extraction tower and enters the downstream low-temperature filter section through a short pipe. The polysaccharide solution in the tower is carried into the low-temperature filter section along with the solid residue and then separated. During the conveying process, the dry powder cylinder 12 is opened, and the edible fungus dry powder is added into the screw conveyor 22. The servo motor is driven, and the rotating shaft 21 rotates along the inside of the screw conveyor 22 after it works, gradually pushing the edible fungus dry powder down into the inside of the first extraction tower to complete the auxiliary processing of extraction. Furthermore, during the process of the dried edible fungus powder entering the first extraction tower, the dried edible fungus powder is vibrated by the vibrator 25 and then falls down along the pipe 26; and when the vibrator 25 vibrates, it will drive the vibrating strip 27 to vibrate, and the striking ball 28 will hit the surrounding area, shaking off the arch-shaped accumulation above, thereby facilitating faster extraction and reducing accumulation or blockage.

[0029] like Figures 6 to 7 As shown, the locking component includes a main rod 10, a spiral rotating blade 31, a fine rotating blade 32, and a filter cylinder 33; The main rod 10 is located at one end of the through pipe 7 near the sealing cylinder 8, and a fixing collar adapted to the spring 35 is provided on its outer side; Multiple spiral rotating blades 31 and fine rotating blades 32 are provided and fixedly installed on the outside of the main rod 10; The filter cartridge 33 is made of ceramic material, and its outer wall is fitted with the scraper and is located inside the double cooling seat 9. The double cooling seat 9 is connected to the sealed cylinder 8. The double cooling seat 9 has a jacketed structure. The jacket is used to circulate cold water to stabilize the temperature of the low-temperature filtration process at 50 to 60 degrees Celsius. The circulating cold water comes from an independent low-temperature cooling circulation device, such as a chiller. This device is equipped with a temperature controller, which can set and stabilize the output cooling water temperature within the range of 5 to 15 degrees Celsius. By adjusting the cooling water flow rate and temperature, it is sufficient to offset the frictional heat generated during the filtration process and the external heat exchange, so that the material temperature in the filter cylinder 33 area is always maintained within the target range of 50 to 60 degrees Celsius.

[0030] The sealing cylinder 8 is located at one end of the through pipe 7 near the double cold seat 9.

[0031] The scraping components include a scraper 34 and a spring 35; The scraper 34 is located on the inner side of the double cooling seat 9, and the cutting edge of the scraper 34 is in contact with the inner wall of the filter cylinder 33. A retaining collar adapted to spring 35 is provided on the outer side of the main rod 10; One end of the spring 35 is set at one end of the scraper 34, and the other end is sleeved in the fixing collar on the main rod 10; the spring 35 provides preload to keep the scraper 34 in contact with the inner wall of the filter cylinder 33, which is used to scrape off residue and prevent the micropores of the filter cylinder 33 from becoming clogged.

[0032] The pumping control assembly includes control components connected to the solvent tank 5 for regulating the countercurrent delivery of solvent; the control components include insert 14, assembly box 15, thin tube 13, assembly shell 16, first conduit 29, second conduit 30, peristaltic tube 19, fixing key 17 and peristaltic pump 18. Insert 14 is disposed through the inside of sieve plate 11 and extends into the inside of extraction tower 4; Assembly box 15 is located at the top of insert 14; The thin tube 13 is disposed inside the sieve plate 11; The assembly shell 16 is positioned below the placement platform 3; The first conduit 29 penetrates one side of the assembled shell 16; The second conduit 30 is fixedly installed above the first conduit 29; The peristaltic tube 19 is disposed on the inner side of the assembly shell 16; The fixing key 17 is located on one side of the peristaltic tube 19; The peristaltic pump 18 is rotatably disposed inside the assembly housing 16; The control components also include an automatic control valve assembly connected in series between the peristaltic tube 19 and the solvent tank 5, which is used to regulate the solvent delivery flow rate and pressure.

[0033] Specifically, the peristaltic pump 18 is positioned between the sealed cylinder 8 and the third extraction tower, acting as a connecting bridge between the two. It is connected to the peristaltic tube 19 on one side of the pump 18. The solvent tank 5 utilizes gravity to assist solvent flow, reducing the workload of the peristaltic pump and ensuring more stable feeding. The fixing key 17 is used to secure the peristaltic tube 19. The first conduit 29 and the second conduit 30 are used to extract the liquid or dried edible fungus powder. The insert 14 and the thin tube 13 have a solvent inlet pipe and a solvent distributor at their top ends, allowing fresh extraction solvent to be transported from the solvent tank 5 to the third extraction tower via the thin tube 13. The key inlet for countercurrent extraction is equipped with an auxiliary exhaust valve and pressure gauge. One end of the solvent inlet pipe is connected to the outlet of solvent tank 5 via a short pipe, passing through a peristaltic pump and an automatic control valve group. The solvent distributor evenly sprays the solvent from the solvent inlet pipe onto the material layer inside the tower to ensure full contact extraction. One end of the sealed cylinder 8 is equipped with a short pipe to introduce the material into the interior. A direct drive motor is installed at one end of the main rod 10, which facilitates the driving of the main rod 10. The filter cartridge 33 is made of ceramic material, which has high temperature resistance to prevent damage caused by heat over time. In practical applications, the mixture of solid bacterial residue, polysaccharide solution, and residual solvent flowing out from the bottom of the third extraction tower forms a mixed solid residue. This mixture of solid residue enters the mechanical interior of the sealed cylinder 8 through the front feed inlet via a short-through pipe and falls onto the rotating spiral blade 31. The two rub against each other, and the spiral blade 31 carries the solid residue forward. As the pitch gradually decreases and the conveying space becomes narrower, it generates gentle mechanical pressure on the solid residue. That is, the fine rotating blade 32 rotates, squeezing out the polysaccharide solution wrapped in the slurry. At the same time, the friction between the residue particles further breaks down the unbroken bacterial cell walls, allowing the residual polysaccharides to fully dissolve, thus having the function of extracting residues. In addition, circulating cold water is continuously introduced into the jacket of the outer double cold seat 9, which carries away the frictional heat generated by the extrusion and the external heat through heat conduction, keeping the temperature of the entire pressing and filtration process stable at 50 to 60 degrees Celsius, ensuring that the activity of the target components is completely unaffected. When the pre-compressed slurry enters the sealed cylinder 8, it is blocked by the area enclosed by the filter cylinder 33. The spiral rotating blade 31 continuously applies thrust, and the polysaccharide solution quickly passes through the micropores of the ceramic filter cylinder 33 under pressure and enters the filtrate collection chamber between the outer sealed cylinder 8 and the filter cylinder 33. This process is completed instantaneously, and the extracted clear liquid does not need to stay for a long time to avoid heat exposure. In addition, when the main rod 10 rotates, the scraper 34 and the spiral rotating blade 31 move at the same speed, and the retractable scraper 34 in the latter half rotates synchronously. Since the scraper 34 is pressed against the inner wall of the filter cylinder 33 by the spring 35, it will continuously scrape off the solid slag attached to the inner wall of the filter cylinder 33 during the rotation process, which completely prevents the micropores from clogging. At the same time, the scraped solid slag will be pushed forward by the thrust of the spiral rotating blade 31 and the rotation force of the scraper 34, and the solid slag at the tail end will be continuously discharged from the discharge port. It should be noted that a waste hopper can be directly placed on the outside of the discharge port for positioning. like Figure 2 , Figure 8 As shown, the receiving component includes a support platform 36, a collection box 37, a slide rail 39, a drive slider 41, and a connector 40; Support platform 36 is installed on the bottom wall inside box 1; The collection box 37 is fixedly installed above the support platform 36; The slide rail 39 is fixedly installed behind the support platform 36; Drive slider 41, which is slidably connected to the inside of slide rail 39; The connector 40 extends through the inside of the drive slider 41.

[0034] The recyclable components include evaporator 38, funnel 43, and insert 42; Evaporator 38 extends through the interior of drive slider 41; The funnel 43 has a hollow interior and penetrates the interior of the mounting platform 3, and is used to introduce the extracted liquid into the evaporator 38. The insertion tube 42 is inserted and installed below the placement platform 3; The inside of funnel 43 is hollow; Specifically, the support platform 36 is used to support the evaporator 38; the vacuum pump is located on one side of the evaporator 38; the drive slider 41 is used to easily adjust the up and down position; the insertion tube 42 is used to guide solid residue to the evaporation equipment; a vacuum pump and a temperature controller are provided on one side of the slide rail 39 for temperature and moisture control; the evaporator 38 is used for evaporation. In practical applications, the extract flowing out from the third extraction tower enters directly into the funnel 43 at the upper feed inlet of the evaporator 38 through a short-pass pipe, without intermediate storage. After the vacuum pump starts, a low-pressure environment is formed inside the evaporator 38, and the temperature controller stabilizes the temperature of the evaporator 38 at 40 to 50 degrees Celsius. The evaporator 38 can be a jacketed rotary evaporator 38 or a scraped thin-film evaporator 38. Its jacket is connected to a precision constant-temperature circulating tank to provide a constant-temperature heat medium at 40 to 50 degrees Celsius. The temperature controller is installed inside the evaporator. The temperature probe monitors the material temperature and achieves precise control of the evaporation temperature by adjusting the output of the constant temperature circulation tank or the power of the auxiliary electric heater. A vacuum regulating valve and a vacuum gauge are provided between the vacuum pump and the evaporator 38 to set and maintain the required vacuum level to reduce the boiling point of the solvent and achieve rapid low-temperature concentration. At this time, the water in the extraction solvent boils and evaporates rapidly at low temperature, while the target component solution molecules do not evaporate and remain in the evaporator 38 to gradually thicken. This process is rapid evaporation, and the polysaccharide is heated for a very short time, so the activity is completely preserved. Solvent recovery and recycling: The evaporated water vapor enters the condensation recovery tank through pipe 26 and is cooled into liquid water. The temperature of the recovered water is 30 to 40 degrees Celsius. It can be directly returned to solvent tank 5 through pipe 26 and reused for countercurrent extraction at the bottom of the third extraction tower, realizing a closed-loop solvent circulation with almost no waste, which will reduce water consumption and production costs. The concentrated polysaccharide solution, with a concentration of 20% or 30%, flows out from the bottom of evaporator 38 and enters the polysaccharide finished product tank. It can then be directly used for drying into powder to complete the extraction process. As a preferred application area of ​​the technical solution of the present invention, it is particularly suitable for extracting heat-sensitive edible fungi polysaccharides from dried edible fungi powder, which can effectively avoid degradation and inactivation during the extraction process and significantly improve extraction efficiency and product quality. As a preferred embodiment of the present invention, the application of this device is described in detail below using the separation of polysaccharides from dried edible fungi powder as an example: Step 1, Feeding and Countercurrent Separation: Edible fungus powder is continuously and quantitatively added to the first-stage extraction tower through the feeding section; at the same time, the separation solvent is pumped from the bottom of the last-stage extraction tower through the pumping control component, flowing upwards against the flow direction of the edible fungus powder, and achieving countercurrent separation of polysaccharides and edible fungus powder at a constant temperature of 50 to 60 degrees Celsius, obtaining a polysaccharide-rich separation liquid from the first-stage extraction tower; Step 2, Low-temperature filtration of slurry: The solid residue discharged from the last stage extraction tower is sent to the low-temperature filtration section and squeezed and filtered under a controlled temperature of 50 to 60 degrees Celsius to separate the residual polysaccharide liquid. Step 3: Low-temperature concentration of the clear liquid and solvent recovery: Combine the separated liquid and the clear liquid, and concentrate them under vacuum conditions at 40 to 50 degrees Celsius to obtain polysaccharide concentrate. The evaporated water is condensed and recovered to the solvent tank for recycling.

[0035] Working Principle: The working principle of this invention is mainly based on the synergy of three core processes: multi-stage countercurrent extraction, low-temperature mechanical pressure filtration, and low-temperature vacuum concentration. During operation, two countercurrent main material flows are formed: Edible mushroom powder is fed into the first-stage extraction tower via a quantitative feed section and moves downwards stage by stage under gravity; simultaneously, fresh extraction solvent is pumped in from the bottom of the final-stage extraction tower via a pump control component, penetrating upwards stage against the flow direction of the edible mushroom powder. During this countercurrent contact process, polysaccharides in the raw materials continuously dissolve and accumulate in the solvent, ultimately resulting in a high-concentration extract flowing out from the side of the first-stage extraction tower. The fully extracted solid residue is discharged from the bottom of the final-stage extraction tower and enters the low-temperature pressure filtration section, where it is squeezed and filtered under cooling conditions to further recover residual components. The resulting extract and the filtered liquid are combined and then enter the low-temperature concentration section, where they are rapidly concentrated under low-temperature vacuum to obtain a concentrated extract. Simultaneously, the evaporated solvent is condensed, recovered, and returned to the solvent tank for recycling, thus achieving continuous, low-temperature, and efficient operation throughout the entire process from feeding, extraction, separation to concentration and solvent recovery.

[0036] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A multi-stage countercurrent solid-liquid separation process for extracting polysaccharides from edible fungi, characterized in that, Includes the following steps: Thermosensitive edible fungi are continuously and quantitatively added to the top of the first-stage extraction tower; The separation solvent is pumped in from the bottom of the last stage extraction tower, so that the solvent flows against the flow direction of the edible fungi and passes through at least three extraction towers connected in series. Under constant temperature conditions of 50 to 60 degrees Celsius, multi-stage countercurrent contact separation is carried out in each extraction tower to fully transfer polysaccharides from edible fungi into the solvent, and extracts rich in polysaccharides are obtained from the first extraction tower. The solid residue discharged from the final extraction tower is filtered by pressure. The pressure filtration process is carried out under a temperature control of 50 to 60 degrees Celsius to separate the residual polysaccharide filtrate. The extract and the filtered liquid are combined into a mixed extract, which is then concentrated at 40 to 50 degrees Celsius under vacuum to obtain a polysaccharide concentrate. The evaporated solvent is then condensed and recovered to achieve a closed-loop cycle.

2. A multi-stage countercurrent solid-liquid separation device, applied in a multi-stage countercurrent solid-liquid separation process for extracting polysaccharides from edible fungi as described in claim 1, comprising a housing (1), wherein a mounting platform (3) is provided on the top of the housing (1), characterized in that, Also includes: The multi-stage countercurrent extraction mechanism is set on the placement platform (3) and includes at least three extraction towers (4) connected in series along the material flow direction and a solvent tank (5) for storing solvent; adjacent extraction towers (4) are connected in series through pipes (7), and the outer wall of each extraction tower (4) is provided with a heat-insulating jacket connected to an external constant temperature circulating water bath system; The feeding section is connected to the first-stage extraction tower of the multi-stage countercurrent extraction mechanism and is used to quantitatively deliver edible fungi into the system. The low-temperature pressure filtration section is connected to the slurry outlet of the last stage extraction tower of the multi-stage countercurrent extraction mechanism, and is used to perform low-temperature pressure filtration on the extraction residue at a temperature of fifty to sixty degrees Celsius. The low-temperature concentration section is connected to the clear liquid outlet of the low-temperature pressure filtration section. It is used to concentrate the mixture of the separated liquid produced by multi-stage countercurrent extraction and the residual liquid produced by low-temperature pressure filtration at a low temperature and recover the solvent. The temperature is 40 to 50 degrees Celsius. A pumping control assembly is connected to the solvent tank (5) and the final extraction tower (4) to pump the solvent into the system and drive it to flow countercurrently. The pumping control assembly includes a peristaltic pump, an automatic control valve group and a PID controller. The automatic control valve group includes an electric regulating valve connected in series with the solvent delivery pipeline and a pressure sensor installed at the solvent inlet at the bottom of the final extraction tower (4). The PID controller is electrically connected to the pressure sensor and the electric regulating valve respectively. By comparing the measured pressure value with the set value, the opening of the electric regulating valve is dynamically adjusted to achieve constant and stable controllable pressure for countercurrent solvent delivery.

3. The multi-stage countercurrent solid-liquid separation device according to claim 2, characterized in that: The feeding section includes a dry powder cylinder (12), a screw conveyor (22) and a vibrating element disposed inside the dry powder cylinder (12); the screw conveyor (22) is connected to the vibrating element, which is disposed below the sieve plate (11) at the top of the extraction tower (4).

4. The multi-stage countercurrent solid-liquid separation device according to claim 3, characterized in that: The screw conveyor (22) is controlled by a processor (20), which adjusts the speed of the screw conveyor (22) to control the feed rate based on the sensing signal of the material in the dry powder cylinder (12).

5. The multi-stage countercurrent solid-liquid separation device according to claim 2, characterized in that: The low-temperature filter press includes a sealed cylinder (8) and a double cooling seat (9) disposed therein; the double cooling seat (9) is a jacketed structure used to introduce circulating cooling medium to control the filter press temperature; the sealed cylinder (8) is provided with a filter cylinder (33) and a scraper that cooperates with it.

6. The multi-stage countercurrent solid-liquid separation device according to claim 5, characterized in that: The scraping component includes a scraper (34) that fits against the inner wall of the filter cylinder (33). The scraper (34) is provided with a preload by a spring (35) for scraping off residue from the inner wall of the filter cylinder (33).

7. The multi-stage countercurrent solid-liquid separation device according to claim 2, characterized in that: The low-temperature concentration section includes an evaporator (38), a funnel (43) for introducing the extract into the evaporator (38), and a condensation recovery unit for condensing the evaporated solvent and returning it to the solvent tank (5).

8. The multi-stage countercurrent solid-liquid separation device according to claim 7, characterized in that: The evaporator (38) is slidably mounted on the slide rail (39), and the condensation recovery unit is connected to the solvent tank (5) via a tube (42).

9. The multi-stage countercurrent solid-liquid separation device according to claim 2, characterized in that: The outer side of the box (1) is hinged with a cover plate (2).

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