A device for instant sterilization of edible fungus cultivation substrate and its application

Abstract

The present invention provides an instantaneous sterilization device for edible fungus cultivation substrate. The instantaneous sterilization device includes a flow channel and a screw, wherein the screw is inserted into the flow channel; spiral blades and extrusion pieces are arranged on the outer periphery of the screw, wherein the spiral blades are arranged in sections, and the extrusion piece is arranged between adjacent spiral blades and close to the outlet of the flow channel; the flow area at the extrusion piece is smaller than the flow area at the spiral blade. The present invention adds an extrusion piece to the screw with spiral blades, and the extrusion piece is arranged between the segmented spiral blades to extrude the material in the flow channel without causing blockage, explosion, etc. At the same time, it also provides a larger friction resistance to generate heat when the material passes through, thereby ensuring the generation of the required high temperature and high pressure.

Description

Technical Field

[0001] The invention belongs to the technical field of extrusion devices, and specifically relates to an edible fungus cultivation base material instantaneous sterilization device and application thereof, and is particularly suitable for continuous high-temperature instantaneous sterilization of edible fungus cultivation base materials. Background Art

[0002] Existing screw extruders are mainly used for material processing. The materials undergo shearing, mixing, high temperature and high pressure in the screw extruder, and are finally discharged through the discharge port. The main components of the screw extruder include a feed hopper, a feeding screw, an extrusion screw and an extrusion die head, which are arranged in sequence;

[0003] The extrusion die head of the existing products is a fixed die head, such as Figure 1 and 2 As shown, it is installed on the top of the screw sleeve and fixed by screws. One is a circular iron block with a diameter of about 3~5cm, and the outlet is designed as a circular, diamond, or elliptical outlet, and the outlet size is about 5mm. The materials extruded by existing products are mainly high-starch, high-protein animal and plant raw materials or chemical raw materials such as resin plastics. The high temperature and high pressure generated by external heating and compression ratio changes are mainly used, combined with the huge changes in the inner diameter of the sleeve (≥65mm) and the outlet size of the extrusion die (about 5mm) to achieve the extrusion of materials. Edible fungus cultivation substrates such as sawdust, corn cobs, cottonseed hulls, etc. have the characteristics of high fiber, non-uniformity, and poor fluidity. In our experiments, edible fungus cultivation substrates are very easy to get stuck in existing products. When the outlet size of the extrusion die becomes larger, it also explodes intermittently and violently. It can be seen that the extrusion die is not suitable for edible fungus cultivation materials.

[0004] The extrusion screw of the existing product is composed of a combination of traditional spirals with pitches of 48mm, 36mm, 24mm, and 20mm. The change in pitch produces a compression ratio of the material. The high temperature and high pressure required for sterilization in a short time (≤120s) cannot be formed by simply changing the compression ratio, and the sterilization effect cannot be achieved. At the same time, such a spiral has limited shearing and homogenizing effects on high-fiber materials, and cannot complete the homogenization and refinement of large-particle materials such as edible fungus cultivation substrates. The material size is uneven, and the sterilization effect on edible fungus cultivation substrates is poor.

[0005] When the moisture content of the material is greater than 25%, the relative gap between the screw and the sleeve of the existing product is relatively large, and the high-humidity, high-fiber and large-particle material has a relatively low compactness during the extrusion process. Once high-pressure steam is formed, it is easy to flow to the low-pressure area, making it difficult to create a high-temperature and high-pressure sterilization environment.

[0006] The extrusion screw of the existing product has a 48mm pitch spiral adjacent to the feed port. When faced with high-moisture edible fungus cultivation substrate, water and material are returned, and the feed cannot be fed smoothly. Summary of the invention

[0007] Therefore, the present invention provides an instantaneous sterilization device for edible fungus cultivation substrate, which is suitable for continuous extrusion sterilization of edible fungus cultivation substrate, and can solve the problem in the prior art that edible fungus cultivation substrate is very easy to get stuck in existing products, and when the outlet size of the extrusion die becomes larger, it also explodes intermittently and violently, indicating that the extrusion die is not suitable for edible fungus cultivation materials.

[0008] In order to solve the above problems, the present invention provides an instantaneous sterilization device for edible fungus cultivation substrate, which includes a screw extrusion assembly and an extrusion device, wherein the screw extrusion assembly includes:

[0009] A flow channel and a screw, wherein the screw is inserted into the flow channel;

[0010] The outer circumference of the screw is provided with spiral sheets and extrusion pieces. The spiral sheets are arranged in sections. The extrusion pieces are arranged between adjacent spiral sheets and close to the outlet of the flow channel. The flow area at the extrusion piece is smaller than the flow area at the spiral sheets. By adding an extrusion piece to the screw with spiral sheets, the extrusion piece is arranged between the segmented spiral sheets, and the material in the flow channel is squeezed without blockage, explosion, etc. At the same time, a certain resistance is given to the material when it passes through, ensuring the required high temperature and high pressure.

[0011] Optionally, a homogenizing component is further provided on the outer periphery of the screw to shear, crush and homogenize the flowing material in the flow channel; the homogenizing component is provided upstream of the extruder.

[0012] Optionally, the homogenizing component includes a shearing spiral blade and a homogenizing ring, and the shearing spiral blade and the homogenizing ring are sequentially arranged on the outer periphery of the screw along the flow direction of the material.

[0013] Optionally, the homogenizing component further comprises a stirring block, and the stirring block is arranged between the shearing spiral blade and the homogenizing ring.

[0014] Optionally, a pressure-maintaining and anti-return component is also provided on the outer periphery of the screw to maintain the pressure of the material in the flow channel and prevent its backflow; the pressure-maintaining and anti-return component is arranged upstream of the extrusion member; when a homogenizing component is provided on the screw, the homogenizing component is arranged in the pressure-maintaining and anti-return component.

[0015] Optionally, the pressure-maintaining and anti-return assembly includes a check ring and a booster ring, and the check ring and the booster ring are sequentially arranged on the outer periphery of the screw along the flow direction of the material.

[0016] Optionally, the screw is further provided with a shearing piece, which includes a shearing spiral blade to perform shear-type crushing on the material in the flow channel.

[0017] Optionally, along the flow direction of the material, a check ring, a shear spiral blade, a spiral blade, a stirring block, a shear spiral blade, a spiral blade, a homogenizing ring, a shear spiral blade, a boosting ring, a spiral blade and an extrusion piece are sequentially arranged on the screw.

[0018] Optionally, a spiral sheet sleeved on the screw is further provided downstream of the extruder.

[0019] According to another aspect of the present invention, an extrusion device is provided, comprising the screw extrusion assembly as described above.

[0020] The screw is selected to be a twin-screw structure. Along the flow direction of the material, the temperature between the flow channel inlet and the check ring is 65°C, the temperature between the check ring and the homogenizing ring is 110°C, and the temperature between the homogenizing ring and the flow channel outlet is 135°C.

[0021] The present invention first replaces the conventional extrusion die head with a built-in extrusion module (extrusion part) to ensure that the edible fungus cultivation base material passes through the screw smoothly without blockage, explosion and the like, while giving the material a certain resistance when passing through, ensuring the high temperature and high pressure required for extrusion.

[0022] Furthermore, the use of a shearing homogenizing component instead of a spiral device can achieve the shearing and crushing function of the present invention for bulk materials of edible fungi cultivation substrates such as sawdust, corn cobs, etc., and strengthens the shearing and crushing, water-material mixing, refinement and homogenization, friction extrusion, tumbling collision and other effects in the process of extrusion and transportation of the matrix material, thereby achieving uniform and rapid heating and temperature maintenance of the material and uniform state of the extruded material, and realizing rapid extrusion and self-heating of the edible fungi cultivation substrate without a die head.

[0023] Furthermore, the pressure-maintaining and anti-returning component in the instantaneous sterilization device for edible fungi cultivation substrate of the present invention is designed by the conical cross-section of the check ring, that is, the material entry point has a large opening, and the material exit point has a small opening, which is similar to a trumpet mouth that is easy to enter but difficult to exit, and there is a continuous supply of materials sent by the screw rod rotating rapidly at the inlet end. After the material enters from the large mouth, it needs to come out from the small mouth, thereby forming a certain pressure to achieve the effect of maintaining pressure and preventing backflow. This prevents the phenomenon of backflow and return of materials at the feed end, and can significantly improve the moisture adaptability of the raw materials of the screw extruder, solve the technical problem that the general screw extruder is only suitable for processing low-moisture (moisture content ≤ 25%) materials, and can extrude and process high-moisture materials (moisture content ≥ 40%), especially high-moisture edible fungi cultivation substrate. At the same time, the pressure-maintaining and anti-returning device increases the pressure and temperature of the sealing area between the two rings, and finally forms an independent high-temperature and high-pressure area and has the effect of preventing high-moisture reflux, which is more conducive to the realization of the sterilization effect, and can be used for instantaneous sterilization equipment for edible fungi cultivation substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1It is a schematic diagram of the structure of a traditional screw extruder;

[0025] Figure 2 It is a schematic diagram of the structure of a traditional screw extruder;

[0026] Figure 3 It is a structural schematic diagram of a screw extruder according to an embodiment of the present invention;

[0027] Figure 4 It is a schematic structural diagram of a screw extrusion assembly according to an embodiment of the present invention.

[0028] The reference numerals are:

[0029] 1. Main motor; 2. Feeding motor; 3. Feed hopper; 4. Feeding screw; 5. Extrusion screw; 9. Extrusion die; 10. Sleeve; 11. Discharge port; 12. Built-in module; 13. Check ring; 14. Boosting ring; 18. Shear spiral blade; 19. Stirring block; 20. Homogenizing ring; 21. Spiral blade. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0031] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0032] See also Figure 3 to Figure 4 As shown, according to an embodiment of the present invention, the instantaneous sterilization device for edible fungus cultivation substrate includes a screw extrusion assembly, which includes:

[0033] A flow channel and a screw, wherein the screw is inserted into the flow channel;

[0034] The outer periphery of the screw is provided with spiral sheets 21 and extrusion pieces. The spiral sheets 21 are arranged in sections. The extrusion pieces are arranged between adjacent spiral sheets 21 and close to the outlet of the flow channel. The flow area at the extrusion pieces is smaller than the flow area at the spiral sheets 21.

[0035] The present invention adds an extrusion piece to the screw with spiral pieces 21. The extrusion piece is arranged between the segmented spiral pieces 21 to extrude the material in the flow channel without causing blockage, explosion and the like. At the same time, it also provides a certain resistance when the material passes through, ensuring the generation of the required high temperature and high pressure.

[0036] Since the extrusion piece is arranged on the outer circumference of the screw and rotates with the screw, the flow area at the extrusion piece is small and its rotation radius is relatively large. The material will be blocked when passing through the extrusion piece, so that the pressure can be increased and the material will not explode at the outlet.

[0037] The flow channel mentioned here generally refers to a screw arranged in the sleeve 10 , and a gap between the screw and the sleeve 10 , where the material flows, forming a flow channel.

[0038] In some embodiments, a homogenizing component is further provided on the outer periphery of the screw to shear, crush and homogenize the flowing material in the flow channel; the homogenizing component is provided upstream of the extruder.

[0039] A homogenizing component is sleeved on the screw to shear and crush the material and then further homogenize it, so that the uniformity of the material is greatly improved. In the processing of edible fungus cultivation substrates, the shearing and crushing function of the present invention can be achieved for large pieces of materials such as wood chips, corn cobs, etc. of the edible fungus cultivation substrate, and the shearing and crushing, water-material mixing, refinement and homogenization, friction extrusion, tumble collision and other effects in the process of extrusion and transportation of the matrix material are strengthened, thereby achieving uniform and rapid heating and temperature maintenance of the material and uniform state of the extruded material, and realizing rapid extrusion and self-heating of the edible fungus cultivation substrate without a die head.

[0040] The preferred structure of the homogenizing component may include a shearing spiral blade 18 and a homogenizing ring 20, wherein the shearing spiral blade 18 and the homogenizing ring 20 are sequentially arranged on the outer periphery of the screw along the flow direction of the material.

[0041] The shearing spiral blade 18 is used to shear the material, so that the material in the flow channel is further broken and refined, and the subsequent homogenization degree is also improved. More preferably, the homogenization component also includes a stirring block 19, and the stirring block 19 is arranged between the shearing spiral blade 18 and the homogenization ring 20.

[0042] The sheared material is stirred to improve the uniformity of the material and enhance the homogenization effect.

[0043] In some embodiments, a pressure-maintaining and anti-return component is also provided on the outer periphery of the screw to maintain the pressure of the material in the flow channel and prevent its backflow; the pressure-maintaining and anti-return component is arranged upstream of the extrusion member; when a homogenizing component is provided on the screw, the homogenizing component is arranged in the pressure-maintaining and anti-return component.

[0044] The pressure-maintaining and anti-return component can prevent the phenomenon of water return at the feed end, which can significantly improve the moisture adaptability of the raw materials of the screw extruder, solve the technical problem that the general screw extruder is only suitable for processing low-moisture (moisture content ≤ 25%) materials, and can extrude and process high-moisture materials (moisture content ≥ 40%), especially high-moisture edible fungus cultivation substrates. At the same time, the pressure-maintaining and anti-return device increases the pressure and temperature of the sealing area between the two rings, and finally forms an independent high-temperature and high-pressure area and has the function of preventing high-moisture reflux, which is more conducive to the realization of the sterilization effect, and lays the foundation for the development of a new screw extrusion sterilization equipment for edible fungus cultivation substrates.

[0045] The specific pressure-maintaining and anti-return assembly includes a check ring 13 and a boost ring 14, which are arranged on the outer periphery of the screw in sequence along the flow direction of the material. The check ring 13 is a conical cross-section design, that is, the opening at the material entry point is large, and the opening at the material exit point is small, similar to a bell mouth that is easy to enter but difficult to exit, and there is a continuous flow of materials sent by the fast-rotating screw at the inlet end. After the material enters from the large opening, it needs to come out from the small opening, thereby forming a certain pressure to achieve the effect of maintaining pressure and preventing water return.

[0046] The check ring 13 is sleeved on the screw to prevent the material from flowing in reverse. Combined with the booster ring 14, the material between the check ring 13 and the booster ring 14 is pressurized and heated, which is beneficial to the heating and sterilization effect of the material. The check ring 13 can be set as a beveled circular ring on one side and a straight surface structure perpendicular to the screw on the other side, so that the material is not easy to flow back after flowing along the bevel to the other side; and the booster ring 14 can be a circular ring or a stepped circular ring, which hinders the flow of the material, so that the material can only flow through the periphery of the booster ring 14 after being squeezed and the pressure is increased.

[0047] In some embodiments, the screw is further provided with a shearing piece, which includes a shearing spiral blade 18 for shearing and crushing the material in the flow channel.

[0048] In order to facilitate the uneven heating of the material in the flow channel, a shearing piece is added to the screw, specifically a shearing spiral blade 18, to shear and crush the material, so that the material is evenly dispersed and the uniformity of the extruded material is greatly improved.

[0049] In some embodiments, along the flow direction of the material, the screw is sequentially provided with a check ring 13, a shear spiral blade 18, a spiral blade 21, a stirring block 19, a shear spiral blade 18, a spiral blade 21, a homogenizing ring 20, a shear spiral blade 18, a boosting ring 14, a spiral blade 21 and an extrusion piece.

[0050] The best extrusion method is that the material passes through the check ring 13 in sequence to prevent it from flowing back, and then is crushed under the shearing of the shear spiral blade 18, and then is pushed through the traditional spiral blade 21, and the material is further dispersed and evenly dispersed through the action of the stirring block 19, and then is sheared and crushed by the shear spiral blade 18 again, and is homogenized by the push of the spiral blade 21, and then passes through the shear spiral blade 18 and the boost ring 14 to quickly heat up the material. A section of the traditional spiral blade 21 is retained between the boost ring 14 and the extrusion piece to increase the driving force of the raw material forward, ensuring that the raw material can smoothly pass through the built-in extrusion die head 9 module to avoid jamming.

[0051] In some embodiments, a spiral sheet 21 sleeved on the screw is further provided downstream of the extruder.

[0052] A conventional spiral sheet 21 is installed after the extrusion element to ensure that the raw materials can be discharged at a uniform speed after sterilization, so as to facilitate the subsequent spiral-free pipeline transportation of the sterilized materials.

[0053] According to another aspect of the present invention, an extrusion device is provided, comprising the screw extrusion assembly as described above.

[0054] In some embodiments, the screw is a twin-screw structure. Along the flow direction of the material, the temperature between the flow channel inlet and the check ring 13 is 65°C, the temperature between the check ring 13 and the homogenizing ring 20 is 110°C, and the temperature between the homogenizing ring 20 and the flow channel outlet is 135°C.

[0055] The twin-screw extruder of the instantaneous sterilization device for edible fungus cultivation substrate of the present invention can sterilize while extruding, without the need for an additional heating device. The preset temperatures of the three zones during sterilization processing are 50-90°C, 100-140°C, and 125-160°C respectively; the three temperature compensation systems can be preheated before the sterilization processing, and the sterilization processing can be carried out after the three temperatures reach the preset temperatures; the screw speed during the sterilization processing is 100-250rpm, and the raw material feeding amount is preferably a maximum feeding amount when a small amount of material is occasionally accumulated at the feeding port to a half-saturated feeding amount.

[0056] The extrusion device of the instantaneous sterilization device for edible fungus cultivation substrate of the present invention is used for continuous extrusion sterilization of edible fungus cultivation substrate, such as Figure 3 and 4As shown, the discharge port 11 of the feeder is connected to the feed port of the screw extruder; the feeder includes a feeding motor 2, a feed hopper 3, and a feeding screw 4. The feed hopper 3 is arranged on the feeding screw 4, and the rotating shaft of the feeding motor 2 is connected to the feeding screw 4; the screw extruder includes a main motor 1, an extrusion screw 5, a sleeve 10, and a partition temperature compensation system corresponding to the extrusion screw 5. The built-in extrusion modules are installed in pairs on the extrusion screw 5 at a distance of 1160 to 150 mm from the discharge port. The booster ring 14 near the discharge end is installed at a position 100-150 mm away from the built-in extrusion part to the feed end, and a check ring 13 near the feed end is installed at a position 500-1100 mm away from the starting end of the screw. The moisture range of the edible fungus cultivation matrix raw material is 10%-60%, and the mixing and moistening time of the ingredients is ≥10min, which can be applied to the extrusion device of the present invention.

[0057] A control experiment was set up to further illustrate the beneficial effects of the present invention through the experimental results. A shiitake mushroom cultivation base material with a moisture content of 50% was prepared and fed into a screw extruder for extrusion processing, and the effects of processing smoothness, extrusion discharge stability, heating working time, sterilization rate, etc. were observed. The extrusion sterilization process conditions were: the temperatures of the three zones were 65°C in zone I, 110°C in zone II, and 135°C in zone III, the screw speed was 160rpm, and the raw material feeding amount was fed at the maximum feeding amount.

[0058] The extrusion experiment was set up as follows: Control group 1: using a traditional twin-screw extruder with a traditional screw and an extrusion die 9 to extrude the cultivation base material; Control group 2: using a screw extruder with a single built-in extrusion die 9 module to extrude the cultivation base material; Control group 3: using a screw extruder with a single shearing homogenization combined alternative spiral device to extrude the cultivation base material; Control group 4: using a screw extruder with a single pressure-maintaining and anti-backflow device to extrude the cultivation base material; Experimental group: using the instantaneous sterilization device for edible fungus cultivation base material of the present invention to extrude the cultivation base material. The experimental results are shown in Table 1.

[0059] Table 1 Comparison of experimental results

[0060]

[0061] As can be seen from Table 1, when the high-moisture shiitake mushroom cultivation base material is extruded and sterilized, when using a traditional screw extruder or a certain specific device in the present invention, there are phenomena such as backflow and material return, or the discharge is not smooth and the explosion is serious, and the sterilization process cannot be completed smoothly. When the composite screw of the instantaneous sterilization device of the edible fungus cultivation base material of the present invention is used for extrusion, no obvious backflow is observed, and the feeding is smooth, because the unique design of the present invention prevents the generated water vapor from returning to the area near the feed port without affecting the smooth passage of the base material, avoids the occurrence of backflow, ensures the smooth progress of extrusion, and realizes the extrusion processing of high-moisture materials. At the same time, the superposition effect formed by the uniquely designed built-in extrusion module, the shearing homogenization combined generation spiral device, and the pressure-maintaining anti-backflow device becomes an independent high-temperature and high-pressure area, which prompts the cultivation base material to heat up quickly and maintain high temperature, significantly improves the self-heating capacity of the cultivation base material, and realizes the uniform shearing of the material while ensuring the sterilization effect, reducing energy consumption.

[0062] Example 2

[0063] The extrusion device of the instantaneous sterilization device for edible fungi cultivation substrate of the present invention specially introduces a built-in extrusion piece 12, a shearing homogenization combined alternative spiral device (including a shearing spiral blade 18, a stirring block 19 and a homogenization ring 20), and a pressure-maintaining anti-water-backflow device (including a check ring 13 and a booster ring 14) to replace part of the traditional spiral blade 21, forming a set of composite extrusion screws suitable for extrusion processing of edible fungi cultivation substrate. The built-in extrusion piece 12 is installed in pairs on the extrusion screw 5 at a distance of 80 mm from the discharge port 11. A section of 80 mm long spiral is installed behind the built-in extrusion piece 12 to ensure that the raw material can be output at a uniform speed after sterilization, so as to facilitate the subsequent spiral-free pipeline transportation of the sterilized material. The pressure-maintaining anti-water-backflow device is two pairs of disc-shaped components, forming a high-temperature and high-pressure sterilization area. The boost ring 14 in the pressure-maintaining and anti-backflow device is installed between the built-in extrusion module 12 and the feed end, and the distance 16 between the built-in extrusion module 12 is 100mm. The check ring 13 is installed at a position 17 1000mm away from the starting end of the screw. A 100mm long traditional spiral is retained between the boost ring 14 and the built-in extrusion module 12 to increase the driving force for the forward movement of the raw materials and ensure that the raw materials can pass through the built-in extrusion die module smoothly to avoid jamming. The shearing homogenizing combined spiral device includes a shearing spiral blade 18, a stirring block 19, and a homogenizing ring 20. Starting from the feed end, the shearing spiral blade 18, the stirring block 19, and the homogenizing ring 20 are installed in pairs in two pairs of extrusion zone II 17 at a distance of 250mm in sequence. The distance 22 between the homogenizing ring 20 and the boost ring 14 is 500mm.

[0064] The prepared 50% moisture content of the oyster mushroom cultivation base material was fed into the screw extruder for extrusion processing, and the processing smoothness, extrusion discharge stability, heating working time, sterilization rate and other effects were observed. The extrusion sterilization process conditions were: the temperatures of the three zones were 65°C in zone I, 110°C in zone II, and 135°C in zone III, the screw speed was 160rpm, and the raw material feeding amount was fed at the maximum feeding amount.

[0065] The extrusion experiment was set up as follows: Control group 1: a traditional twin-screw extruder with a traditional screw and an extrusion die was used to extrude the cultivation base material; Control group 2: a screw extruder with a single built-in extrusion module was used to extrude the cultivation base material; Control group 3: a screw extruder with a single shearing homogenization combined alternative spiral device was used to extrude the cultivation base material; Control group 4: a screw extruder with a single pressure-maintaining and anti-backflow device was used to extrude the cultivation base material; Experimental group: the instantaneous sterilization device for edible fungus cultivation base material of the present invention was used to extrude the cultivation base material. The experimental results are shown in Table 2.

[0066] Table 2 Comparison of experimental results

[0067] Processing smoothness Discharge stability Heating working time Sterilization rate Control group 1 6 minutes after the extrusion started, a large amount of water and material began to return, and the material could not be fed smoothly. The material discharge from the discharge port is not smooth, and the explosion phenomenon is serious The average heating rate is 1.45℃ / min, and the heating working time is: 70% in zone I, 75% in zone II, and 75% in zone III. 61.20% Control group 2 8 minutes after the extrusion started, a large amount of water and material began to return, and the material could not be fed smoothly. After the water is returned, the material in the feed port is blocked, and the material out of the discharge port is normal The average heating rate is 1.56℃ / min, and the heating working time is: 55% in zone I, 59% in zone II, and 55% in zone III 73.41% Control group 3 8 minutes after the extrusion started, a large amount of water and material began to return, and the material could not be fed smoothly. After the water is returned, the material inlet is blocked, the material outlet is not smooth, and the explosion phenomenon is serious The average heating rate is 1.73℃ / min, and the heating working time is: 55% in zone I, 40% in zone II, and 50% in zone III. 85.23% Control group 4 There was no obvious water return during the entire sterilization process, and the feed was smoothly The material discharge from the discharge port is not smooth, and the explosion phenomenon is serious The average heating rate is 1.85℃ / min, and the heating working time is: 55% in zone I, 30% in zone II, and 50% in zone III. 90.23% Experimental Group There was no obvious water return during the entire sterilization process, and the feed was smoothly The feeding port feeds smoothly and stably, and the discharging port discharges smoothly and stably. The average heating rate is 2.23℃ / min, and the heating working time is: 50% in zone I, 20% in zone II, and 25% in zone III. 99.54%

[0068] As can be seen from Table 2, when the high-moisture mushroom cultivation base material is extruded and sterilized, when using a traditional screw extruder or a partial structure of the extrusion device of the present invention, there are phenomena such as backflow and material return, or severe explosion of the material discharge, and the sterilization process cannot be completed smoothly. However, when the composite screw of the device of the present invention is used for extrusion, no obvious backflow is observed, and the material is fed smoothly. This is because the unique design of the present invention prevents the generated water vapor from returning to the area near the feed port while not affecting the smooth passage of the base material, avoids the occurrence of backflow, ensures the smooth progress of extrusion, and realizes the extrusion processing of high-moisture materials. At the same time, the superposition effect formed by the uniquely designed built-in extrusion module, the shearing homogenization combined generation spiral device, and the pressure-maintaining anti-backflow device forms an independent high-temperature and high-pressure area, which prompts the cultivation base material to heat up quickly and maintain high temperature, significantly improves the self-heating capacity of the cultivation base material, and realizes the uniform shearing of the material while ensuring the sterilization effect, reducing energy consumption.

[0069] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention. The above description is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present invention. These improvements and variations should also be regarded as the protection scope of the present invention.

Claims

1. An instantaneous sterilization device for edible fungus cultivation substrate, comprising a screw extrusion assembly, characterized in that: The screw extrusion assembly comprises: A flow channel and a screw, wherein the screw is inserted into the flow channel; The outer circumference of the screw is provided with a spiral sheet (21) and an extrusion piece, the spiral sheet (21) is arranged in sections, and the extrusion piece is arranged between adjacent spiral sheets (21) and close to the outlet of the flow channel; the flow area at the extrusion piece is smaller than the flow area at the spiral sheet (21); A homogenizing component is also provided on the outer periphery of the screw to shear, crush and homogenize the flowing material in the flow channel; the homogenizing component is provided upstream of the extruder; The homogenizing component comprises a shearing spiral blade (18) and a homogenizing ring (20), wherein the shearing spiral blade (18) and the homogenizing ring (20) are sequentially arranged on the outer periphery of the screw along the flow direction of the material; The homogenizing component further comprises a stirring block (19), wherein the stirring block (19) is arranged between the shear spiral blade (18) and the homogenizing ring (20); A pressure-maintaining and anti-return component is also provided on the outer periphery of the screw to maintain the pressure of the material in the flow channel and prevent its backflow; the pressure-maintaining and anti-return component is arranged upstream of the extruder; when a homogenizing component is provided on the screw, the homogenizing component is arranged in the pressure-maintaining and anti-return component; Along the flow direction of the material, the screw is provided with a check ring (13), a shear spiral sheet (18), a spiral sheet (21), a stirring block (19), a shear spiral sheet (18), a spiral sheet (21), a homogenizing ring (20), a shear spiral sheet (18), a boosting ring (14), a spiral sheet (21) and an extrusion piece in sequence.

2. The instantaneous sterilization device for edible fungus cultivation substrate according to claim 1, characterized in that: The pressure-maintaining and anti-return assembly comprises a check ring (13) and a pressure-boosting ring (14), and the check ring (13) and the pressure-boosting ring (14) are arranged in sequence on the outer periphery of the screw along the flow direction of the material.

3. The instantaneous sterilization device for edible fungus cultivation substrate according to claim 1, characterized in that: The screw rod is also provided with a shearing piece, which includes a shearing spiral blade (18) for shearing and crushing the material in the flow channel.

4. The instantaneous sterilization device for edible fungus cultivation substrate according to claim 1, characterized in that: A spiral sheet (21) sleeved on the screw is also provided downstream of the extruder.

5. The instantaneous sterilization device for edible fungus cultivation substrate according to claim 1, characterized in that: The screw is a twin-screw structure. Along the flow direction of the material, the temperature between the flow channel inlet and the check ring (13) is 65°C, the temperature between the check ring (13) and the homogenizing ring (20) is 110°C, and the temperature between the homogenizing ring (20) and the flow channel outlet is 135°C.

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