CN114603818A

CN114603818A - Double-screw extruder for biodegradable material

Info

Publication number: CN114603818A
Application number: CN202210295222.5A
Authority: CN
Inventors: 帅词俊; 戚方伟
Original assignee: Jiangxi University of Science and Technology
Current assignee: Jiangxi University of Science and Technology
Priority date: 2022-03-24
Filing date: 2022-03-24
Publication date: 2022-06-10
Anticipated expiration: 2042-03-24
Also published as: CN114603818B

Abstract

The invention discloses a double-screw extruder facing to biodegradable materials, which comprises: a segmented barrel comprising a plurality of spaced apart heated barrels; a cooling unit is arranged among the plurality of heating machine barrels; the input end of the sectional type machine barrel is provided with a feeding unit for introducing materials; an extrusion unit for guiding out materials is arranged in the sectional type machine barrel. The invention designs and develops a sectional type heating cylinder body and a double-inlet and double-outlet water channel system, realizes the accurate and independent control of the temperature of different processing sections, and solves the common problem of local high-temperature degradation caused by the incapability of quick temperature response in the traditional extrusion, thereby manufacturing the biodegradable polymer composite material with uniform physical properties with high stability and high productivity.

Description

Double-screw extruder for biodegradable material

Technical Field

The invention relates to the field of processing of biodegradable materials, in particular to a double-screw extruder for biodegradable materials.

Background

Biodegradable polymers are basic raw materials for preparing regenerated tissues and organs, but a single biodegradable polymer material is difficult to meet the performance requirements of the regenerated tissues and organs. Melt extrusion processing is an important means for realizing melt mixing, plasticizing wrapping and the like of high molecules and other functional materials, and has positive effects on functionalization, high performance and recombination of regenerated tissues and organs. However, as a heat-sensitive material, a biodegradable polymer is very susceptible to thermo-oxidative degradation during a long-term extrusion process.

At present, in the extrusion processing equipment in the market, the problems of high-temperature degradation and carbonization, scaling of the inner wall of a flow channel, oxidative degradation, unstable extrusion and the like easily occur in the processing process of degradable polymers due to the fact that the screw thread lead is not matched with the residence time and plasticizing mixing effect of materials, the water cooling effect is poor, the shear stress on the flow channel wall is unstable, the response of a temperature control system is slow, protective gas cannot be filled into a high-pressure extruder and the like; in addition, when various degradable materials are processed and mixed, the processes of proportioning and storing various raw materials, classifying and leading in are too complicated, the feeding speed and proportion of various materials are difficult to regulate and control, and the labor intensity is too high, so that the problem that the quality of finished products based on subsequent melting and mixing is poor is caused.

Disclosure of Invention

An object of the present invention is to solve at least the above problems and/or disadvantages and to provide at least the advantages described hereinafter. To achieve these objects and other advantages in accordance with the present invention, there is provided a twin-screw extruder facing a biodegradable material, comprising:

a segmented barrel comprising a plurality of spaced apart heated barrels; a cooling unit is arranged among the plurality of heating machine barrels; the input end of the sectional type machine barrel is provided with a feeding unit for introducing materials; an extrusion unit for guiding out materials is arranged in the sectional type machine barrel.

Preferably, wherein the cooling unit comprises: a cooling machine barrel is arranged among the plurality of heating machine barrels; the lower ends of the plurality of cooling machine barrels are connected with a cooling water tank capable of circularly collecting and discharging liquid; a water pump is arranged in the cooling water tank, and the input end and the output end are respectively connected with a cooling water inlet header pipe and a cooling water outlet header pipe; a cooling manifold with a plurality of built-in water paths is arranged between the cooling water inlet header pipe and the cooling water outlet header pipe; double inlet and outlet cooling pipes are respectively arranged between the cooling machine barrels and the cooling manifold; the double inlet and outlet cooling pipes respectively comprise an inner cooling pipe and an outer cooling pipe; two ends of the internal cooling pipe are butted to the cooling manifold; the middle part of the inner cooling pipe is wound into a plurality of circles and is attached and fixed on the outer wall of the cooling machine barrel; the two ends of the outer cooling pipe are butted to a cooling manifold; the middle part of the outer cooling pipe is wound into a plurality of circles and is fixedly attached to the outer layer of the inner cooling pipe, so that a cooling water channel with double inlet and double outlet is formed; the two ends of the inner cooling pipe and the outer cooling pipe are arranged in a front-back manner along the axis of the cooling machine barrel and are positioned at the same side of the cooling machine barrel.

Preferably, wherein the feeding unit comprises a batching bucket; four material guiding bins with openings at the upper ends are arranged in the batching barrel; support columns are integrally connected with the middle parts of the four material guide bins; the bottoms of the four material guiding bins incline inwards, are uniformly converged to form a leakage opening, and extend downwards to form a material discharging pipe; the leakage openings are arranged below the supporting columns at intervals; a stepped discharging plate capable of being drawn out outwards is slidably arranged above the bottoms of the four material guide bins; sliding chutes I are arranged on two sides above the bottoms of the four material guide bins; sliding strips I which can be respectively embedded into the two sliding grooves I are arranged on two sides of the four stepped discharging plates, so that sliding connection is formed; the lower end of the support column is provided with a plurality of limiting grooves; the front ends of the four stepped discharging plates are provided with handles; wedge blocks clamped into the limiting grooves are arranged at the rear ends of the four stepped discharging plates; four positioning pin holes are formed in the four stepped discharging plates at intervals; and four sliding bolts which are vertically downward and matched with the four positioning pin holes are arranged on the side surfaces of the material guiding bin.

Preferably, a vibration frame is arranged in the batching barrel; the support column is of a hollow structure; the middle part of the vibration frame is provided with a sliding rod movably arranged in the supporting column in a penetrating way; linear bearings are arranged at two ends of the supporting column; the upper end of the sliding rod is fixedly arranged on the inner ring of one of the linear bearings, and a material turning frame is fixedly arranged after the sliding rod penetrates out; the upper end of the material turning frame is fixedly connected with the output end of a linear reciprocating motor; the material turning frame comprises four material turning rods which respectively extend into the four material guiding bins; a plurality of inclined rods are arranged on the four material turning rods at intervals; a plurality of turning pieces are transversely arranged on the plurality of inclined rods respectively; the lower end of the sliding rod is fixedly arranged on the inner ring of the other linear bearing and is fixedly provided with a material homogenizing table after penetrating out; the material homogenizing table is suspended and penetrated in the discharge pipe; the material mixing table is provided with a material turning claw in a cross structure; the upper ends of the four material turning claws are respectively provided with two cambered surfaces which are propped against the middle.

Preferably, the device also comprises a screw feeder; the output end of the spiral feeder is connected to the first section of the sectional type machine barrel; a conical discharge hopper is integrally arranged at the lower end of the batching barrel; the input end of the spiral feeder is connected to the lower port of the discharge hopper; the middle part of the discharge hopper is transversely provided with a push-pull plate in a sliding manner; a strip-shaped sliding frame penetrates through the side surface of the discharge hopper; sliding chutes II are arranged on two sides of the sliding frame; sliding strips II which can be respectively embedded into the two sliding grooves II are arranged on the two sides of the push-pull plate, so that slidable connection is realized; the push-pull plate is provided with a large flow limiting opening, a middle flow limiting opening and a small flow limiting opening which can be in matched butt joint with the discharge pipe; elastic baffles are arranged on two sides of the middle flow limiting port; and one side of the small flow limiting port and one side of the large lower flow limiting port are respectively provided with a fixed baffle.

Preferably, wherein the extrusion unit comprises: the large-lead double screws are arranged in different directions and axially and rotatably penetrate through the sectional type machine barrel; the double-screw external spline key teeth incline by 1 degree.

Preferably, the device further comprises a power unit; the power unit includes: a feed motor and a spindle motor; the feeding motor is arranged in front of the feeding unit, and the spindle motor is arranged in front of the sectional type machine barrel and is connected with the double screws through a gearbox.

Preferably, wherein, a heating unit is further included; the heating unit includes: the electromagnetic valve, the heater and the temperature control meter; the heater has a plurality of, and sets up respectively in a plurality of heating barrel.

Preferably, the device further comprises a protection unit; the protection unit includes: an air inlet pipe, a booster pump, an air outlet pipe and a nitrogen tank; the input end of the booster pump is connected with the nitrogen tank through an air outlet pipe; and the output end of the booster pump is connected to the first section of the sectional type machine barrel through an air outlet pipe.

Preferably, wherein, an operation unit is further included; the operating unit comprises a control frame fixedly arranged on one side of the sectional type machine barrel; and a display control screen is arranged on the control frame.

The invention at least comprises the following beneficial effects:

the invention designs and develops a sectional type heating cylinder and a double-inlet and double-outlet water channel system, realizes the accurate and independent control of the temperature of different processing sections, and solves the common problem of local high-temperature degradation caused by the incapability of quick temperature response in the traditional extrusion; a supercharged nitrogen injection protection system is configured, so that the thermal oxidative degradation of the biological material in a high-temperature environment is effectively prevented; based on the key technical units, the extrusion equipment for melting and mixing the biodegradable high polymer is integrated and developed; the anisotropic large-lead thread structure realizes circumferential flow and material exchange of polymer melt and overcomes the antagonistic problem of long-time stay degradation and insufficient plasticizing mixing of thermosensitive polymers; the involute small-angle spline connection technology is provided, the stability of the shear stress on the wall of the runner is ensured, and the key technical bottleneck of scaling and static layer formation on the inner wall of the runner is broken through; the cooling units which are arranged at intervals in a matched mode of a plurality of heating machine barrels in the sectional type machine barrel are adopted, so that the accurate independent control of the temperatures of different processing sections (heating machine barrels) is realized, the common problem of local high-temperature degradation caused by the fact that the traditional melting material extrusion process cannot be quickly subjected to temperature response is solved, and the stable and efficient preparation of the biodegradable material is realized.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.

Drawings

FIG. 1 is a general block diagram of the present invention;

FIG. 2 is a view of the structure of the double inlet and outlet cooling pipes of the present invention;

FIG. 3 is a detailed block diagram of the feed unit of the present invention;

FIG. 4 is a top view of the refining table of the present invention;

FIG. 5 is a top view of the dispensing bin of the present invention;

FIG. 6 is a top view of the push-pull plate of the present invention;

FIG. 7 is a side view of one of the twin screws of the present invention;

FIG. 8 is an external spline tooth of one of the twin screws of the present invention;

Detailed Description

The present invention is further described in detail below with reference to the attached drawings so that those skilled in the art can implement the invention by referring to the description text. It will be understood that terms such as "having," "including," and "comprising," as used herein, do not preclude the presence or addition of one or more other elements or groups thereof. It is to be understood that in the description of the present invention, the terms indicating orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are used only for convenience in describing the present invention and for simplification of the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. In the description of the present invention, unless otherwise specifically stated or limited, the terms "mounted," "disposed," "sleeved/connected," "connected," and the like are used broadly, and for example, "connected" may be a fixed connection, a detachable connection, or an integral connection, a mechanical connection, an electrical connection, a direct connection, an indirect connection via an intermediate medium, or a communication between two elements, and those skilled in the art will understand the specific meaning of the terms in the present invention specifically. Further, in the present invention, unless explicitly stated or limited otherwise, reference to a first feature "on" or "under" a second feature can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact via an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature.

Fig. 1-8 illustrate one implementation of the present invention, including:

a segmented barrel 1 comprising a plurality of spaced apart heated barrels 11; a cooling unit 2 is arranged among a plurality of heating machine barrels 11; the input end of the sectional type machine barrel 1 is provided with a feeding unit 3 for introducing materials; an extrusion unit 4 for discharging the material is arranged inside the sectional type machine barrel 1.

The working principle is as follows: when the invention is used, a material to be processed is led into the feeding unit 3, the feeding unit 3 successively feeds the material into the sectional barrel 1, the preset heating temperature of each stage of heating barrel 11 is installed, a heating device in the heating barrel 11 uniformly heats and melts the material, the material is uniformly stirred and extruded through the extruding unit 4, the cooling units 2 arranged at intervals start to refrigerate, the heating barrels 11 at each stage are correspondingly cooled, the material is circularly operated in the sectional barrel 1 in the whole flow of melting, stirring and extruding according to the flows of heating → cooling → heating → cooling, and the like, and finally the material is discharged until the molten material is led out.

The technical scheme has the advantages that: according to the invention, the plurality of heating machine barrels 11 in the sectional type machine barrel 1 are matched with the cooling units 2 which are arranged at intervals, so that the accurate independent control of the temperatures of different processing sections (the heating machine barrels 11) is realized, the common problem of local high-temperature degradation caused by the incapability of quick temperature response in the traditional molten material extrusion process is solved, and the biodegradable high polymer composite material with uniform physical properties can be manufactured with high stability and high productivity.

In the above technical solution, the cooling unit 2 includes: a cooling cylinder 21 is arranged among the plurality of heating cylinders 11; the lower ends of the plurality of cooling machine barrels 21 are connected with a cooling water tank 22 capable of circularly collecting and discharging liquid; a water pump is arranged in the cooling water tank 22, and the input end and the output end are respectively connected with a cooling water inlet header pipe 23 and a cooling water outlet header pipe 24; a cooling manifold 25 with a plurality of built-in water paths is arranged between the cooling water inlet manifold 23 and the cooling water outlet manifold 24; a plurality of cooling machine barrels 21 and cooling manifolds 25 are respectively provided with double inlet and outlet cooling pipes 26; the double inlet and outlet cooling pipes 26 respectively comprise an inner cooling pipe 261 and an outer cooling pipe 262; the internal cooling tube 261 is butted against the cooling manifold 25 at both ends (i.e., water inlet end, water outlet end); the middle part of the internal cooling pipe 261 is wound into a plurality of circles and is attached and fixed on the outer wall of the cooling machine barrel 21; the outer cooling tube 262 is butted at both ends (i.e., water inlet end, water outlet end) to the cooling manifold 25; the middle part of the outer cooling pipe 262 is coiled into a plurality of circles and is attached and fixed on the outer layer of the inner cooling pipe 261, so that a cooling water channel with double inlet and double outlet is formed; the two ends of the inner cooling pipe 261 and the outer cooling pipe 262 are arranged in tandem along the axis of the cooling cylinder 21 and are located on the same side of the cooling cylinder 21.

The technical scheme has the advantages that:

(1) all parts in the cooling unit 2 jointly form a double-inlet and double-outlet water channel system, so that the cooling efficiency of each cooling machine barrel 21 is further improved, and by matching with the sectional type machine barrel 1, the common problem of local high-temperature degradation caused by incapability of quick temperature response in the melt extrusion of degradable materials in the traditional process is solved, so that the materials in the sectional type machine barrel 1 can be cooled to different degrees in the cooling machine barrels 21 arranged at intervals, and the preparation efficiency and the finished product quality of the melt extrusion of the degradable materials can be remarkably improved by the process;

(2) compared with single water channel cooling, the double-inlet and double-outlet water channel has better heat transfer effect; meanwhile, the double inlet and outlet cooling pipes 26 with the outer ring wrapping the inner ring have the significance that the water outlet end of the outer ring can take away the heat of the inner ring, and the cooling water inlet end can take away the heat of the cooling water outlet end, so that the double inlet and outlet cooling pipes are in a circulating cooling mode, the heat transfer effect is better, the cooling of the cylinder is uniform, and the cylinder is not easy to deform;

(3) meanwhile, the double water channels of the double inlet and outlet cooling pipes 26 are arranged front and back with respect to the axis of the cooling cylinder 21, and compared with the traditional left and right arrangement of the double water channels, the length of the cooling area is not increased, but the installation space is saved, and the material cost is also saved.

In the above technical solution, the feeding unit 3 comprises a batching barrel 31; four material guiding bins 32 with openings at the upper ends are arranged in the batching barrel 31; the middle parts of the four material guiding bins 32 are integrally connected with supporting columns 321; the bottoms of the four material guiding bins 32 are inclined inwards, are uniformly converged to form a leakage opening, and extend downwards to form a material discharging pipe 322; the leakage openings are arranged below the supporting columns 321 at intervals; a stepped discharging plate 33 which can be drawn out outwards is slidably arranged above the bottoms of the four material guiding bins 32; sliding chutes I are arranged on two sides above the bottoms of the four material guide bins 32; sliding strips I which can be respectively embedded into the two sliding grooves I are arranged on two sides of the four stepped discharging plates 33, so that sliding connection is formed; the lower end of the support column 321 is provided with a plurality of limiting grooves 320; the front ends of the four stepped discharging plates 33 are provided with handles; the rear ends of the four stepped discharging plates are provided with wedge blocks 330 clamped in the limiting grooves 320; four positioning pin holes 331 are formed in the four stepped discharging plates 33 at intervals; the four guide bins 32 are provided with sliding bolts 323 which are vertically downward and matched with the four positioning pin holes 331 on the side.

The advantages of this solution are: firstly, the batching barrel 31 is provided with four material guiding bins 32, so that various degradable materials can be distributed and stored in advance, and the preliminary material mixing treatment of different materials is facilitated; the supporting columns 321 are used for connecting the side walls of the four material guiding bins 32, so that the fixing is more stable; when the ingredient is introduced, the four positioning pin holes can be regarded as big and small gears of the discharge amount of each material guide bin, namely, the material guide bins with more proportion need to be added, the stepped discharge plate can be drawn out to the maximum extent, the sliding bolt 323 is inserted into the positioning pin hole at the rightmost end of the stepped discharge plate, a maximum space for guiding out the material can be drawn, namely, the amount of the material flowing out of the material guide bin is controlled by fixing the sliding bolt with each positioning pin hole; through carrying out different above-mentioned configurations in four different guide feed bins, just can form the different mixing proportion of deriving the material in four guide feed bins, realize the function of a material mixing proportion adjustment, the material that mixes can be unified arranges the discharge tube 322 and discharges downwards, has accomplished the unified discharge function of misce bene material.

In the above technical solution, a vibration frame 34 is arranged in the batching barrel 31; the support column is of a hollow structure; the middle part of the vibration frame 34 is provided with a sliding rod 341 movably arranged in the supporting column 321 in a penetrating way; two ends of the support column 321 are provided with linear bearings 342; the upper end of the sliding rod 341 is fixedly arranged on the inner ring of one of the linear bearings 342, and the material turning frame 35 is fixedly arranged after the upper end penetrates out; the upper end of the material turning frame 35 is fixedly connected with the output end of a linear reciprocating motor 350; the material overturning frame 35 comprises four material overturning rods 351 which respectively extend into the four material guiding bins 32; a plurality of inclined rods 352 are arranged on the four material turning rods 351 at intervals; a plurality of turning pieces 353 are transversely arranged on the plurality of inclined rods 352 respectively; the lower end of the sliding rod 341 is fixedly arranged on the inner ring of the other linear bearing 342 and is fixedly provided with a material homogenizing table 36 after penetrating out; the material homogenizing table 36 is suspended and penetrated in the discharge pipe 322; the material mixing table 36 is provided with a material turning claw 361 with a cross structure; the upper ends of the four turning claws 361 are respectively provided with two cambered surfaces 362 which are propped against each other in the middle;

the advantages of this solution are:

(1) the materials in the four material guiding bins 32 are uniformly turned over together by using a vibration frame 34 with a composite structure; the sliding rod 341, as a sliding member, slides in the middle of the hollow fixing column 321, and performs stable up-and-down reciprocating motion through the two linear bearings 342, and the linear reciprocating motor 350 provides motion power; after the four material turning rods 351 respectively extend into the material guiding bin 32, the material turning rods 351 are matched with the material turning pieces 353 on the plurality of inclined rods 352 to perform stable up-and-down circular material turning, so that the materials can be stably and uniformly guided out from the lower part;

(2) the material homogenizing table 36 below the vibration rack also shakes up and down along with the sliding rod 341, so that different materials gathered from four directions can be scattered, mixed into a more uniform state and then discharged downwards; meanwhile, the four material turning claws 361 on the material homogenizing table do continuous up-and-down movement, so that the materials gathered in the material discharging pipe 322 can be prevented from being accumulated, and the material discharging efficiency is improved; two cambered surfaces 362 that lean on to the centre guarantee that granular material can slide whereabouts ability, improve whole row material effect.

In the above technical scheme, the device also comprises a spiral feeder 30; the output end of the screw feeder 30 is connected to the first section of the sectional type machine barrel 1; a conical discharge hopper 311 is integrally arranged at the lower end of the batching barrel 31; the input end of the screw feeder 30 is connected to the lower port of the discharge hopper 311; a push-pull plate 37 is transversely arranged at the middle part of the discharge hopper 311 in a sliding manner; a strip-shaped sliding frame penetrates through the side surface of the discharge hopper 311; sliding chutes II are arranged on two sides of the sliding frame; sliding strips II which can be respectively embedded into the two sliding grooves II are arranged on two sides of the push-pull plate 37, so that slidable connection is realized; the push-pull plate 37 is provided with a large, a medium and a small flow-limiting opening which can be in matched butt joint with the discharge pipe 322; elastic baffles 374 are arranged on two sides of the middle flow limiting opening 372; and one side of the small flow limiting opening 371 and one side of the large lower flow limiting opening 373 are respectively provided with a fixed baffle 375.

The advantages of this solution are: the operator can adjust the push-pull plate by continuous sliding to ensure that different flow-limiting ports are butted to the lower port of the discharge pipe 322, thereby adjusting the final discharge capacity after the materials are mixed; spacing can be realized to two elastic baffle 374, and restriction 372 can accurately dock to arranging port under the material pipe 322 in guaranteeing, and simultaneously when the push-and-pull plate is whole to be dragged, elastic baffle can be compressed, guarantees that big restriction 373 and little restriction 371 can both slide butt joint to arranging the lower port of material pipe 322, and two fixed stop can be just end and the most terminal to the gliding push-and-pull plate realization holistic spacing, make it more stable.

In the above technical solution, the extrusion unit 4 includes: the large-lead double screws 41 are arranged in different directions and axially and rotatably penetrate through the sectional type machine barrel 1; the twin screw 41 external spline teeth 410 are inclined at 1 deg..

This kind of technical scheme has the advantage that: the extrusion unit 4 adopts the double screws 41 with the different-direction large-lead thread structure, thereby realizing the circumferential flow and material exchange of the polymer melt and overcoming the antagonistic problem of long-time stay degradation and insufficient plasticizing mixing of the thermosensitive polymer; meanwhile, the double-screw external spline teeth incline by 1 degree, a gradually-opened small-angle spline connection technology is provided, the stability of shear stress on the wall of the runner is ensured, and the key technical bottleneck of scaling and static layer formation on the inner wall of the runner is broken through.

In the technical scheme, the device further comprises a power unit; the power unit includes: a feed motor 51 and a spindle motor 52; the feed motor 51 is arranged in front of the feed unit 3, and the spindle motor 52 is arranged in front of the sectional barrel 1 and is connected to the twin screw 41 via a gearbox 53.

The technical scheme has the advantages that: the feeding motor 51 and the spindle motor 52 which are configured on the power unit 5 provide stable and controllable power energy for relevant running equipment of the extrusion unit and the feeding unit, the configuration is convenient, and the material extrusion is more stable.

In the above technical solution, the apparatus further comprises a heating unit; the heating unit includes: the electromagnetic valve, the heater and the temperature control meter; the heaters 61 are provided in plural and are respectively provided in the plural heater barrels 11.

The technical scheme has the advantages that: through the individual equipment in the heating unit, for heating the barrel and providing heating power, the configuration is convenient, and heating temperature regulates and control easily.

In the above technical solution, the apparatus further comprises a protection unit; the protection unit includes: an air inlet pipe 71, a booster pump 72, an air outlet pipe 73 and a nitrogen tank 74; the input end of the booster pump 72 is connected with a nitrogen tank 74 through an air outlet pipe 73; the output of the booster pump 72 is connected to the first section of the sectional barrel 1 via an outlet pipe 73.

The technical scheme has the advantages that: each equipment of the protection unit forms a supercharged nitrogen injection protection system, and in the melting and extrusion process of the degradable materials, nitrogen is continuously introduced for cooperation, so that the thermal oxidative degradation of the degradable biological materials in a high-temperature environment can be effectively prevented, and the preparation quality of hot-melt material mixing is improved.

In the above technical solution, the device further comprises an operation unit; the operating unit comprises a control frame 81 fixedly arranged on one side of the sectional type machine barrel 1; a display control screen 82 is arranged on the control frame 81.

The technical scheme has the advantages that: the operator can control the relevant operation equipment by controlling the display control screen 82 in time, the control is convenient, and the parameter adjustment is in time.

Example 1:

the heating temperature of each section of the heating machine barrel 11 is respectively set as follows: 220 ℃, 210 ℃, 205 ℃, 200 ℃ and 185 ℃, and keeping for 30 minutes after reaching the set temperature; opening a switch of a nitrogen tank 74, and opening a booster pump 72; fully mixing 45% of the levorotatory polylactic acid and 55% of hydroxyapatite by mass, and adding the mixture into a feeding unit 3; the material of the feeding unit 3 conveys the powder raw material to the head end of the sectional type machine barrel 1 along the distribution direction of the feeding pipe; setting the extrusion rate of the large-lead twin-screw 41 to 110 r/min; turning on the cooling unit 2 to inject cooling water to keep the temperature of each heating cylinder 11 constant; the materials entering the heating machine barrel 11 are melted under the action of a heating device and the strong shearing force of the double screws 41, and then are dispersed, distributed and mixed; finally, the material is extruded from a die at the end of the segmented barrel 11 by twin screw 41 extrusion.

Example 2:

the heating temperature of each section of the heating machine barrel 11 is respectively set as follows: 230 ℃, 220 ℃, 195 ℃, 190 ℃ and 185 ℃, and keeping for 30 minutes after reaching the set temperature; opening a switch of a nitrogen tank 74, and opening a booster pump 72; fully mixing 40% of the levorotatory polylactic acid and 60% of hydroxyapatite by mass, and adding the mixture into a feeding unit 3; the material of the feeding unit 3 conveys the powder raw material to the head end of the sectional type machine barrel 1 along the distribution direction of the feeding pipe; setting the extrusion rate of the large-lead twin-screw 41 to 110 r/min; turning on the cooling unit 2 to inject cooling water to keep the temperature of each heating cylinder 11 constant; the materials entering the heating machine barrel 11 are melted under the action of a heating device and the strong shearing force of the double screws 41, and then are dispersed, distributed and mixed; finally, the material is extruded from a die at the end of the segmented barrel 11 by twin screw 41 extrusion.

Example 3:

the heating temperature of each section of the heating machine barrel 11 is respectively set as follows: 210 ℃, 200 ℃, 190 ℃, 185 ℃ and 180 ℃, and keeping for 30 minutes after reaching the set temperature; opening a switch of a nitrogen tank 74, and opening a booster pump 72; fully mixing 30% by mass of levorotatory polylactic acid, 60% by mass of hydroxyapatite and 10% by mass of polyethylene glycol, and adding the mixture into a feeding unit 3; the material of the feeding unit 3 conveys the powder raw material to the head end of the sectional type machine barrel 1 along the distribution direction of the feeding pipe; setting the extrusion rate of the large-lead twin-screw 41 to 110 r/min; turning on the cooling unit 2 to inject cooling water to keep the temperature of each heating cylinder 11 constant; the materials entering the heating machine barrel 11 are melted under the action of a heating device and the strong shearing force of the double screws 41, and then are dispersed, distributed and mixed; finally, the material is extruded from a die at the end of the segmented barrel 11 by twin screw 41 extrusion.

The number of apparatuses and the scale of the process described herein are intended to simplify the description of the present invention. Applications, modifications and variations of the present invention will be apparent to those skilled in the art. While embodiments of the invention have been described above, it is not limited to the applications set forth in the description and the embodiments, which are fully applicable in various fields of endeavor to which the invention pertains, and further modifications may readily be made by those skilled in the art, it being understood that the invention is not limited to the details shown and described herein without departing from the general concept defined by the appended claims and their equivalents.

Claims

1. A twin-screw extruder facing a biodegradable material, characterized in that it comprises:

2. The twin-screw extruder towards biodegradable materials according to claim 1, characterized in that said cooling unit comprises: a cooling machine barrel is arranged among the plurality of heating machine barrels; the lower ends of the plurality of cooling machine barrels are connected with a cooling water tank capable of circularly collecting and discharging liquid; a water pump is arranged in the cooling water tank, and the input end and the output end are respectively connected with a cooling water inlet header pipe and a cooling water outlet header pipe; a cooling manifold with a plurality of built-in water paths is arranged between the cooling water inlet header pipe and the cooling water outlet header pipe; double inlet and outlet cooling pipes are respectively arranged between the plurality of cooling machine barrels and the cooling manifold; the double inlet and outlet cooling pipes respectively comprise an inner cooling pipe and an outer cooling pipe; two ends of the internal cooling pipe are butted to the cooling manifold; the middle part of the inner cooling pipe is wound into a plurality of circles and is attached and fixed on the outer wall of the cooling machine barrel; the two ends of the outer cooling pipe are butted to a cooling manifold; the middle part of the outer cooling pipe is wound into a plurality of circles and is fixedly attached to the outer layer of the inner cooling pipe, so that a cooling water channel with double inlet and double outlet is formed; the two ends of the inner cooling pipe and the outer cooling pipe are arranged in a front-back manner along the axis of the cooling machine barrel and are positioned at the same side of the cooling machine barrel.

3. The twin screw extruder facing biodegradable material of claim 1, wherein the feeding unit comprises a compounding barrel; four material guiding bins with openings at the upper ends are arranged in the batching barrel; support columns are integrally connected with the middle parts of the four material guide bins; the bottoms of the four material guiding bins incline inwards, are uniformly converged to form a leakage opening, and extend downwards to form a material discharging pipe; the leakage openings are arranged below the supporting columns at intervals; a stepped discharging plate capable of being drawn out outwards is slidably arranged above the bottoms of the four material guide bins; sliding chutes I are arranged on two sides above the bottoms of the four material guide bins; sliding strips I which can be respectively embedded into the two sliding grooves I are arranged on two sides of the four stepped discharging plates, so that sliding connection is formed; the lower end of the support column is provided with a plurality of limiting grooves; the front ends of the four stepped discharging plates are provided with handles; wedge blocks clamped into the limiting grooves are arranged at the rear ends of the four stepped discharging plates; four positioning pin holes are formed in the four stepped discharging plates at intervals; and four sliding bolts which are vertically downward and matched with the four positioning pin holes are arranged on the side surfaces of the material guiding bin.

4. The twin screw extruder for biodegradable material according to claim 3, wherein a vibration frame is provided in the dispensing barrel; the support column is of a hollow structure; the middle part of the vibration frame is provided with a sliding rod movably arranged in the supporting column in a penetrating way; linear bearings are arranged at two ends of the supporting column; the upper end of the sliding rod is fixedly arranged on the inner ring of one of the linear bearings, and a material turning frame is fixedly arranged after the sliding rod penetrates out; the upper end of the material turning frame is fixedly connected with the output end of a linear reciprocating motor; the material turning frame comprises four material turning rods which respectively extend into the four material guiding bins; a plurality of inclined rods are arranged on the four material turning rods at intervals; a plurality of turning pieces are transversely arranged on the plurality of inclined rods respectively; the lower end of the sliding rod is fixedly arranged on the inner ring of the other linear bearing and is fixedly provided with a material homogenizing table after penetrating out; the material homogenizing table is suspended and penetrated in the discharge pipe; the material mixing table is provided with a material turning claw in a cross structure; the upper ends of the four material turning claws are respectively provided with two cambered surfaces which are propped against the middle.

5. A twin screw extruder facing biodegradable material according to claim 3, further comprising a screw feeder; the output end of the spiral feeder is connected to the first section of the sectional type machine barrel; a conical discharge hopper is integrally arranged at the lower end of the batching barrel; the input end of the spiral feeder is connected to the lower port of the discharge hopper; the middle part of the discharge hopper is transversely provided with a push-pull plate in a sliding manner; a strip-shaped sliding frame penetrates through the side face of the discharge hopper; sliding chutes II are arranged on two sides of the sliding frame; sliding strips II which can be respectively embedded into the two sliding grooves II are arranged on the two sides of the push-pull plate, so that slidable connection is realized; the push-pull plate is provided with a large flow limiting opening, a middle flow limiting opening and a small flow limiting opening which can be in matched butt joint with the discharge pipe; elastic baffles are arranged on two sides of the middle flow limiting port; and one side of the small flow limiting port and one side of the large lower flow limiting port are respectively provided with a fixed baffle.

6. A twin-screw extruder facing a biodegradable material according to claim 1, characterized in that said extrusion unit comprises: the large-lead double screws are arranged in different directions and axially and rotatably penetrate through the sectional type machine barrel; the double-screw external spline teeth incline 1 degree.

7. The twin screw extruder facing a biodegradable material of claim 1, further comprising a power unit; the power unit includes: a feed motor and a spindle motor; the feeding motor is arranged in front of the feeding unit, and the spindle motor is arranged in front of the sectional type machine barrel and is connected with the double screws through a gearbox.

8. The twin screw extruder facing a biodegradable material of claim 1, further comprising a heating unit; the heating unit includes: the electromagnetic valve, the heater and the temperature control meter; the heater is provided with a plurality of heaters which are respectively arranged in a plurality of heating machine barrels.

9. The twin screw extruder facing a biodegradable material of claim 1, further comprising a protective unit; the protection unit includes: an air inlet pipe, a booster pump, an air outlet pipe and a nitrogen tank; the input end of the booster pump is connected with the nitrogen tank through an air outlet pipe; and the output end of the booster pump is connected to the first section of the sectional type machine barrel through an air outlet pipe.

10. The twin screw extruder facing a biodegradable material according to claim 1, further comprising an operation unit; the operation unit comprises a control frame fixedly arranged on one side of the sectional type machine barrel; and a display control screen is arranged on the control frame.