A high-temperature and high-pressure continuous sterilization screw extruder suitable for high-moisture edible fungus cultivation substrate and its application

Abstract

The present invention belongs to the technical field of extrusion devices, and specifically relates to a screw extrusion assembly and an extrusion device, and a high-temperature and high-pressure continuous sterilization screw extrusion device suitable for high-moisture edible fungus cultivation substrate and its application. The screw extrusion assembly includes a screw with a spiral blade on the outer periphery; a check piece is sleeved on the screw and can prevent the material squeezed by the spiral blade from flowing in reverse. The present invention adds a check piece to the screw with a spiral blade, which can prevent the material squeezed by the spiral blade from flowing in reverse as the screw rotates, especially for materials with a high water content, which can only move in the downstream direction under the action of the spiral blade and the check piece, and are squeezed, so that it is easy to form high temperature and high pressure and be sterilized.

Description

Technical Field

[0001] The invention belongs to the technical field of extrusion devices, and specifically relates to a screw extrusion assembly and an extrusion device, and a high-temperature and high-pressure continuous sterilization screw extrusion device suitable for high-moisture edible fungus cultivation substrate and its application. Background Art

[0002] The essential characteristic of edible fungus cultivation substrate is high-fiber and large-particle material. The sealing performance of the screw barrel is poor during the screw extrusion process. Due to the large relative gap between the screw and the sleeve, the high-humidity, high-fiber and large-particle material has a relatively low compactness during the extrusion process. Especially for materials with a moisture content of >25%, 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. Summary of the invention

[0003] Therefore, the present invention provides a screw extrusion assembly and an extrusion device, which can solve the problem in the prior art that it is difficult to create a high-temperature and high-pressure sterilization environment for materials with a moisture content greater than 25%.

[0004] In order to solve the above problems, the present invention provides a screw extrusion assembly, comprising:

[0005] A screw having spiral blades on its outer circumference;

[0006] The check piece is sleeved on the screw and can prevent the material squeezed by the spiral sheet from flowing in the reverse direction.

[0007] Optionally, at least one stop member is provided along the axial direction of the screw rod to divide the spiral sheet into at least two sections.

[0008] Optionally, measured from the screw axis, the check member includes a conical surface and a second surface arranged opposite to each other, the conical surface is located upstream of the second surface in the material flow direction; and the angle between the second surface and the screw axis is set to 80° to 90°.

[0009] Optionally, the angle between the conical surface and the screw axis is set to 30° to 60°.

[0010] Optionally, two screws are arranged side by side, and the two screws are provided with the check piece; the check piece on one screw is staggered with the check piece on the other screw, and the outer peripheral edge of the check piece located upstream abuts against the top of the conical surface of the check piece located downstream with a gap.

[0011] Optionally, the screw extrusion assembly further includes a booster, which is sleeved on the screw and located downstream of the check member; the booster can hinder the forward flow of the material and increase the extrusion force of the material on the spiral blade.

[0012] Optionally, at least one booster is provided along the axial direction of the screw.

[0013] Optionally, measured with respect to the screw axis, the pressure booster includes two end faces arranged opposite to each other, and an angle between the end faces and the screw axis is set to 80° to 90°.

[0014] Optionally, two screws are arranged side by side, and the check member and the booster are provided on both screws. The booster on one screw is staggered with the booster on the other screw, and the end face of the booster located upstream is spaced apart from the end face of the booster located downstream and is arranged opposite to each other.

[0015] Optionally, the gap between the outer peripheral edge of the check member located upstream and the top of the conical surface of the check member located downstream is set to 0.1-1 mm; and / or, the distance between the partial end surface of the supercharger located upstream and the partial end surface facing the supercharger located downstream is set to 0.1-1 mm.

[0016] According to another aspect of the present invention, an extrusion device is provided, comprising the screw extrusion assembly as described above.

[0017] Optionally, the extrusion device further comprises a sleeve, and the screw extrusion assembly is arranged in the sleeve; the distance between the outer periphery of the check member and the inner wall of the sleeve is set to 1 to 10 mm.

[0018] Optionally, the screw extrusion assembly includes a booster, and the distance between the outer periphery of the booster and the inner wall of the sleeve is set to 0.5 to 7 mm; and / or, the distance between the booster and the stop member is set to 300 to 1000 mm; and / or, the distance between the stop member and the upstream end of the screw is 700 to 1200 mm.

[0019] The invention also provides application of the extrusion device in high-temperature and high-pressure continuous sterilization of edible fungus cultivation substrates.

[0020] The present invention adds a check piece to the screw with spiral blades. As the screw rotates, it can prevent the material squeezed by the spiral blades from flowing in reverse. Especially for materials with high water content, under the action of the spiral blades and the check piece, they can only move in the downstream direction, get squeezed, and thus easily form high temperature and high pressure to be sterilized. Therefore, the screw extrusion assembly of the present invention can significantly improve the adaptability of the extruded raw material to moisture, 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 suitable for screw extrusion processing of high-moisture edible fungus cultivation substrates, and has a significant effect of improving and stabilizing the pressure and temperature of the material after passing through the check piece, laying the foundation for the development of a new screw extrusion sterilization equipment for edible fungus cultivation substrates. Further combined with the supercharger, it can hinder the forward flow of the material, increase the extrusion force of the material on the spiral blade, and increase the difficulty of the material flowing in the downstream direction. The material density between the check piece and the supercharger will be improved, further improving the extrusion effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of an extrusion device according to an embodiment of the present invention;

[0022] Figure 2 A schematic structural diagram of a check member according to an embodiment of the present invention;

[0023] Figure 3 Schematic diagram of the structure of a pressure booster according to an embodiment of the present invention.

[0024] The reference numerals are:

[0025] 1. Screw; 2. Sleeve; 3. Feed port; 4. Discharge port; 5. Spiral blade; 6. Check piece; 7. Boosting piece; 8. Gap between check piece and sleeve; 9. Gap between check pieces; 10. Gap between boosting piece and sleeve; 11. Gap between boosting pieces; 12. Distance between check piece and the head end of the screw; 13. Distance between check piece and boosting piece; 14. Enclosed area between check piece and boosting piece. DETAILED DESCRIPTION

[0026] 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.

[0027] 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.

[0028] See also Figure 1 to Figure 2 As shown, according to an embodiment of the present invention, a screw extrusion assembly includes:

[0029] The screw 1 has a spiral sheet 5 on its outer periphery;

[0030] The check member 6 is sleeved on the screw 1 and can prevent the material squeezed by the spiral blade 5 from flowing in the reverse direction.

[0031] The present invention adds a check piece 6 to the screw 1 with the spiral blade 5. As the screw 1 rotates, it can prevent the material squeezed by the spiral blade 5 from flowing in the opposite direction. Especially for materials with a large water content, under the pushing of the spiral blade 5 and the action of the check piece 6, the materials can only move in the downstream direction, get squeezed, and thus easily form high temperature and high pressure for sterilization.

[0032] The screw extrusion assembly of the present invention can significantly improve the moisture adaptability of the extruded raw materials, solve the technical problem that general screw extruders are only suitable for processing low-moisture materials (moisture content ≤ 25%), and can extrude and process high-moisture materials (moisture content ≥ 40%). It is particularly suitable for the screw 1 extrusion processing of high-moisture edible fungus cultivation base materials, and has a significant effect of improving and stabilizing the pressure and temperature of the material after passing through the check piece 6, laying a foundation for the development of a new edible fungus cultivation base material screw 1 extrusion sterilization equipment.

[0033] The check member 6 is sleeved on the screw rod 1 and can be set to be annular, including the check member 6.

[0034] In some embodiments, along the axial direction of the screw 1, at least one, for example, 2, 3, 4, 5 or more stop members 6 are provided to divide the spiral sheet 5 into at least two sections.

[0035] A plurality of check members 6 can be arranged in sections to gradually achieve a squeezing effect on the material, further preventing the backflow of the material with a high water content after being pressurized.

[0036] In some embodiments, the backstop 6 includes a conical surface and a second surface disposed opposite to each other, the conical surface is located upstream of the second surface in the material flow direction, and the angle between the second surface and the axis of the screw 1 is set to 80° to 90°. Preferably, the angle between the conical surface and the axis of the screw 1 is set to 30° to 60°.

[0037] The side of the check member 6 facing the incoming material direction is set as a conical structure to form a large slope with an angle of 30° to 60°, so that the edible fungus cultivation substrate can easily pass through the check member 6 under the pushing of the spiral blade 5; in addition, the back side of the check member 6 is set as a right angle or a slight slope with an angle of 80° to 90° to increase the difficulty of the material, including moisture and steam generated during the extrusion process, to flow back to the feeding section.

[0038] In some embodiments, two screws 1 are arranged side by side, and the two screws 1 are provided with the stop member 6; the stop member 6 on one screw 1 is staggered with the stop member 6 on the other screw 1, and the outer peripheral edge of the stop member 6 located upstream is in gap contact with the top of the conical surface of the stop member 6 located downstream.

[0039] For the twin-screw 1 structure, the check pieces 6 on the two screws 1 are staggered, which can play a buffering extrusion effect and improve the passing rate of the extruded material through the check piece 6.

[0040] like Figure 3 As shown, in some embodiments, the screw extrusion assembly also includes a booster 7, which is sleeved on the screw 1 and located downstream of the check member 6; the booster 7 can hinder the forward flow of the material and increase the extrusion force of the material exerted by the spiral blade 5.

[0041] In order to improve the density of the extruded material, a booster 7 is arranged downstream of the check member 6 to increase the difficulty of the material flowing downstream, so that the density of the material between the check member 6 and the booster 7 is improved. The booster 7 may include a baffle at the discharge port 4, the aperture of which is much smaller than the flow area of ​​the material when the spiral blade 5 is extruded; or an annular structure sleeved on the screw 1, which has a certain distance from the discharge port 4, can also achieve a boosting effect.

[0042] In some embodiments, at least one booster 7 is provided along the axial direction of the screw 1 .

[0043] To increase the pressure of the material, a plurality of, for example, 2, 3, 4 or 5 supercharging parts may be arranged in a 7-stage manner to increase the pressure in steps and reduce the power burden.

[0044] In some embodiments, measured from the axis of the screw 1 , the booster 7 includes two end faces disposed opposite to each other, and the angle between the end faces and the axis of the screw 1 is set to 80° to 90°.

[0045] Both axial ends of the booster 7 are designed to be right angles or slight slopes with an angle of 80° to 90° to increase the difficulty of the passage of materials including water vapor, while slowing down the forward speed of the materials and increasing the extrusion friction of the materials, thereby increasing the pressure and temperature of the enclosed area between the check member 6 and the booster 7, and finally forming an independent high-temperature and high-pressure area that has the function of preventing high-water content from flowing back.

[0046] In some embodiments, two screws 1 are arranged side by side, and the two screws 1 are provided with the check member 6 and the booster 7. The booster 7 on one screw 1 is staggered with the booster 7 on the other screw 1, and the end face of the booster 7 located upstream is arranged opposite to the end face of the booster 7 located downstream.

[0047] For the twin screw 1 structure, the boosters 7 on the parallel screws 1 are also staggered to ensure that when the screw 1 rotates, there is no direct friction between the two boosters 7 and a certain sealing effect on the material. Preferably, the gap between the outer peripheral edge of the upstream stopper 6 and the top of the conical surface of the downstream stopper 6 is set to 0.1-1 mm; and / or, the distance between the partial end surface of the upstream booster 7 and the partial end surface of the downstream booster 7 is set to 0.1-1 mm.

[0048] According to another aspect of the present invention, an extrusion device is provided, comprising the screw extrusion assembly as described above.

[0049] The extrusion device adopts a screw extrusion assembly, in which the check member 6 can be a pair of annular structures, which are sleeved on the screw 1 and combined with the spiral sheet 5 to form a new combined extrusion structure; and the booster 7 sleeved on the downstream can also be set as an annular structure.

[0050] The edible fungus cultivation substrate passes through the check piece 6 and will not be accumulated at the feed end to cause backflow and material return. The check piece 6 can increase the difficulty of the material including moisture and water vapor generated by extrusion to flow back and pass through, avoiding the occurrence of water return during the extrusion of high-moisture materials by the traditional screw 1 extruder, and can significantly improve the moisture adaptability of the raw material of the screw 1 extruder, solve the technical problem that the general screw 1 extruder is only suitable for processing low-moisture materials (moisture content ≤ 25%), and can extrude and process high-moisture materials (moisture content ≥ 40%), especially high-moisture edible fungus cultivation substrates.

[0051] Secondly, the check piece 6 and the booster 7 can slow down the forward speed of the material and increase the extrusion friction of the material. The superimposed effect of the difficulty of water vapor to pass through can increase the pressure and temperature of the sealing area between the check piece 6 and the booster 7, and finally form an independent high-temperature and high-pressure area and have the function of preventing high-water backflow, which is more conducive to the realization of the sterilization effect and lays the foundation for the development of a new edible fungus cultivation substrate screw 1 extrusion sterilization equipment.

[0052] In some embodiments, the extrusion device further comprises a sleeve 2, and the screw extrusion assembly is arranged in the sleeve 2; the distance between the outer periphery of the backstop 6 and the inner wall of the sleeve 2 is set to 1 to 10 mm. Preferably, the screw extrusion assembly comprises a booster 7, and the distance between the outer periphery of the booster 7 and the inner wall of the sleeve 2 is set to 0.5 to 7 mm; and / or, the distance between the booster 7 and the backstop 6 is set to 300 to 1000 mm; and / or, the distance between the backstop 6 and the upstream end of the screw 1 is 700 to 1200 mm.

[0053] The clearance of the outer periphery of the check piece 6 is 0.5 to 3 mm larger than the clearance of the outer periphery of the booster 7, making it easy for materials to enter but difficult to exit. The check piece 6 and the booster 7 are both distributed in the middle and rear part of the sleeve 2. Under the pressure of the spiral sheet 5, it is easy for materials to pass through the check piece 6 and the booster 7.

[0054] The above-mentioned dimensions are mainly set in accordance with the compression ratio of the screw 1, the moisture content of the material, the particle size of the material and the sterilization temperature required for the material. The greater the compression ratio of the screw 1, the lower the moisture content of the material, the larger the particle size of the material and the lower the sterilization temperature required for the material, the greater the outer gap between the ring of the backstop 6 and the sleeve 2, the greater the outer gap between the ring of the booster 7 and the sleeve 2, the smaller the distance between the installation position of the backstop 6 and the feed end of the screw 1, and the smaller the interval between the backstop 6 and the booster 7.

[0055] Example 1

[0056] like Figure 1-3The extrusion device shown in the figure introduces one check member 6 and one supercharger 7, and the check member 6 and the supercharger 7 are separated by a certain distance, which is the distance 13 between the check member and the supercharger, and are respectively placed in the middle and rear area of ​​the screw 1, forming a set of composite extrusion screws suitable for extrusion processing of edible fungus cultivation substrates. The check member 6 and the supercharger 7 are respectively composed of two annular components installed in pairs adjacent to each other, and there is a gap 9 between the two annular rings of the check member 6, and there is a gap 11 between the two annular rings of the supercharger 7. There is a gap 8 between the check member 6 and the sleeve 2, and there is a gap 10 between the supercharger 7 and the sleeve 2. The outer diameter of the above annular components is smaller than the inner diameter of the sleeve 2, and the gap 8 between the check member and the sleeve is larger than the gap 10 between the supercharger and the sleeve by about 0.5 to 3 mm, so that the material is easy to enter and difficult to exit. The edge structures on both sides of the supercharger 7 are right angles. The edge of the check member 6 facing the incoming material direction is a conical large slope structure (angle is 30°~60°), while the edge on the side facing the incoming material direction is designed as a right angle or a slight slope (angle is 80°~90°). The large slope structure is conducive to the rapid passage of large particles of edible fungi matrix materials, and the right angle or slight slope structure is not conducive to the return and passage of materials and water vapor. The installation position of the check member 6 is a certain distance from the feed end of the screw 1, which is the distance 12 between the check member and the head end of the screw. The check member 6 and the supercharger 7 are separated by a certain distance, which is the distance 13 between the check member and the supercharger.

[0057] In the device, the backstop 6 and the supercharger 7 replace part of the traditional spiral blades 5 to form a set of composite extrusion screws suitable for extrusion processing of edible fungus cultivation substrates. The gap between the two circular rings of the backstop 6 is the gap 9 between the backstops, and the gap between the two circular rings of the pressure piece 7 is the gap 11 between the superchargers, both of which are 0.5 mm. The gap 8 between the backstop 6 and the sleeve 2 is 8 mm, and the gap 10 between the supercharger 7 and the sleeve 2 is 5 mm, making it easy for materials to enter and difficult to exit. The edges of the supercharger 7 on both sides are right angles, the edge of the backstop 6 facing the incoming direction is a large slope (angle of 45°), and the edge of the side facing the incoming direction is a right angle. The large slope structure is conducive to the rapid passage of large particles of edible fungus matrix materials, and the right angle structure is not conducive to the return and passage of materials and water vapor. The distance between the installation position of the backstop 6 and the feed end of the screw 1 is 800 mm, and the spacing distance 3 between the backstop 6 and the supercharger 7 is 800 mm.

[0058] A control experiment was set up to further illustrate the beneficial effects of the present invention through the experimental results. A mushroom cultivation base material with a moisture content of 50% was prepared and entered into a screw extruder for extrusion processing. First, an extrusion self-heating experiment was carried out, that is, the external heating was not started, and the temperature rise of the enclosed area was observed to reflect the self-heating of the material under the extrusion shearing action. Then an extrusion sterilization experiment was carried out to observe the effects of backflow and blockage. The extrusion sterilization process conditions are: the temperatures of the three zones are 65°C in zone I, 110°C in zone II, and 135°C in zone III, and the screw speed is 160rpm.

[0059] The extrusion experiment was set up as follows: Control group 1: using a conventional screw and installing an extrusion die to extrude the cultivation base material; Control group 2: using a conventional screw without installing an extrusion die to extrude the cultivation base material; Experimental group 1: using the composite screw of the device of the present invention and installing an extrusion die to extrude the cultivation base material; Experimental group 2: using the composite screw of the device of the present invention without installing an extrusion die to extrude the cultivation base material. The experimental results are shown in Table 1.

[0060] Table 1 Comparison of experimental results

[0061]

[0062] As can be seen from Table 1, when the high-moisture mushroom cultivation base material is extruded using a traditional screw, the feed port has serious water backflow and the material cannot be fed smoothly; however, when the composite screw of the device of the present invention is used for extrusion, no obvious water backflow is observed and the material can be 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 without affecting the smooth passage of the base material, thereby avoiding the occurrence of water backflow, ensuring the smooth extrusion, and realizing the extrusion processing of high-moisture materials. Moreover, as shown in Table 1, the self-heating results show that the enclosed area formed by such a unique design becomes an independent high-temperature and high-pressure area, which prompts the cultivation base material to heat up quickly and maintain high temperature, significantly improving the self-heating capacity of the cultivation base material, and reducing energy consumption while ensuring the sterilization effect.

[0063] Example 2

[0064] The difference from Example 1 is that the gap 8 between the stop member 6 and the sleeve 2 is 6 mm, and the gap 10 between the booster 7 and the sleeve 2 is 3 mm; the distance between the installation position of the stop member 6 and the feed end of the screw 1 is 600 mm, and the interval between the stop member 6 and the booster 7 is 500 mm.

[0065] A control experiment was set up to further illustrate the beneficial effects of the present invention through the experimental results. A 50% moisture content of the oyster mushroom cultivation base material was prepared and entered into a screw extruder for extrusion processing. First, an extrusion self-heating experiment was carried out, that is, the external heating was not started, and the temperature rise of the enclosed area was observed to reflect the self-heating of the material under the extrusion shearing action. Then an extrusion sterilization experiment was carried out to observe the effects of backflow and blockage. The extrusion sterilization process conditions are: the temperatures of the three zones are 65°C in zone I, 110°C in zone II, and 135°C in zone III, and the screw speed is 160rpm.

[0066] The extrusion experiment was set up as follows: Control group 1: using a conventional screw and installing an extrusion die to extrude the cultivation base material; Control group 2: using a conventional screw without installing an extrusion die to extrude the cultivation base material; Experimental group 1: using the composite screw of the device of the present invention and installing an extrusion die to extrude the cultivation base material; Experimental group 2: using the composite screw of the device of the present invention without installing an extrusion die to extrude the cultivation base material. The experimental results are shown in Table 2.

[0067] Table 2 Comparison of experimental results

[0068]

[0069] As can be seen from Table 2, when the high-moisture content oyster mushroom cultivation base material is extruded using a traditional screw, the feed port has serious water backflow and the material cannot be fed smoothly; however, when the composite screw of the device of the present invention is used for extrusion, no obvious water backflow is observed and the material can be 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, thereby avoiding the occurrence of water backflow, ensuring the smooth extrusion, and realizing the extrusion processing of high-moisture content materials. Moreover, as shown in Table 2, the self-heating results show that the enclosed area formed by such a unique design becomes an independent high-temperature and high-pressure area, which prompts the cultivation base material to heat up quickly and maintain high temperature, significantly improving the self-heating capacity of the cultivation base material, and reducing energy consumption while ensuring the sterilization effect.

[0070] It is easy for those skilled in the art to understand that the above-mentioned implementation modes can be freely combined and superimposed without conflict.

[0071] 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. A screw extrusion assembly, characterized in that: include: A screw (1) having a spiral sheet (5) disposed on its outer circumference; A check piece (6) is sleeved on the screw (1) and can prevent the material squeezed by the spiral blade (5) from flowing in the reverse direction; the check piece (6) is provided with at least one to divide the spiral blade (5) into at least two sections; The check member (6) comprises a conical surface and a second surface disposed opposite to each other, the conical surface being located upstream of the second surface in the material flow direction, with respect to the axis of the screw (1); the angle between the second surface and the axis of the screw (1) is set to be 80° to 90°; The angle between the conical surface and the axis of the screw (1) is set to 30° to 60°; The screw extrusion assembly further comprises at least one booster (7), which is sleeved on the screw (1) and located downstream of the check member (6); the booster (7) can hinder the forward flow of the material and increase the extrusion force of the spiral blade (5) on the material; Measured on the axis of the screw (1), the booster (7) comprises two end faces arranged opposite to each other, and the angle between the end faces and the axis of the screw (1) is set to be 80° to 90°.

2. The screw extrusion assembly according to claim 1, characterized in that: The screw rods (1) are provided with two screw rods (1) arranged side by side, and the two screw rods (1) are provided with the check member (6) and the booster member (7), wherein the booster member (7) on one of the screw rods (1) is offset from the booster member (7) on the other screw rod (1), and the end face of the booster member (7) located upstream is arranged opposite to the end face of the booster member (7) located downstream, with a gap therebetween.

3. The screw extrusion assembly according to claim 1, characterized in that: The size of the gap between the outer peripheral edge of the check member (6) located upstream and the top of the conical surface of the check member (6) located downstream is set to 0.1 to 1 mm; and / or, the distance between the partial end surface of the booster member (7) located upstream and the partial end surface facing the booster member (7) located downstream is set to 0.1 to 1 mm; the spacing between the booster member (7) and the check member (6) is set to 300 to 1000 mm.

4. An extrusion device, characterized in that: It comprises a screw extrusion assembly as described in any one of claims 1 to 3, wherein the extrusion device further comprises a sleeve (2), and the screw extrusion assembly is arranged in the sleeve (2); the distance between the outer periphery of the stop member (6) and the inner wall of the sleeve (2) is set to 1 to 10 mm.

5. The extrusion device according to claim 4, characterized in that The distance between the outer periphery of the booster (7) and the inner wall of the sleeve (2) is set to 0.5 to 7 mm; and / or the distance between the stop member (6) and the upstream end of the screw (1) is 700 to 1200 mm.

6. Use of the extrusion device according to claim 4 or 5 in high temperature and high pressure continuous sterilization of edible fungus cultivation substrates.

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