NL2026736A

NL2026736A - A High-Efficiency Continuous Waste Rubber Reclaiming Equipment and Preparation Method

Info

Publication number: NL2026736A
Application number: NL2026736A
Authority: NL
Inventors: Guo Lei; Liu Haichao; Wang Chuansheng; Lv Dejun; Ren Donghui; Zhai Tianjian; Wang Zhi; Zhao Yupeng
Original assignee: Qingdao Univ Of Science And Technology
Priority date: 2019-10-25
Filing date: 2020-10-23
Publication date: 2021-06-22
Also published as: CN110919909B; NL2026736B1; CN110919909A

Abstract

A high-efficiency and continuous waste rubber reclaiming equipment characterized in that: it includes a high-temperature and high-speed mixing device (1), a constant temperature storage 5 hopper (2), a first-stage constant temperature quantitatively metering and conveying device (3), a thermomechanical chemical decoupling system (7), a second-stage constant temperature quantitatively metering and conveying device (19), a low-temperature plasticizing and molding system (20), a shaping device (21), a driving system (4), a transmission system (5), a cooling system (8), a heating system (11) and a frame (6). 10 [Figure 1]

Description

A High-Efficiency Continuous Waste Rubber Reclaiming Equipment and Preparation Method

FIELD OF THE INVENTION The invention relates to the preparation of reclaimed rubber, especially relates to a high- efficiency and continuous waste rubber reclaiming equipment and preparation method.

BACKGROUND With the rapid development of automobile and other industries, the demand for rubber is continuously increasing. The huge demand makes China become the largest rubber consumption country in the world for many years. However, due to the lack of rubber resources in China, nearly 80% of natural rubber and 60% of synthetic rubber depend on imports. As a new type of rubber resources, waste rubber can alleviate the urgent shortage of rubber resources in China if it can be used reasonably. Therefore, making good use of waste rubber and turning waste into treasure have great economic and social benefits.

Rubber reclamation is one of the main recycling methods of waste rubber. It utilizes physical and chemical methods of crushing and high-temperature and mechanical processing to change the vulcanized rubber from elastic state to plastic state. Its essence is to destroy the crosslinking network of the vulcanized rubber through the comprehensive action of heating, oxidation, mechanical force and additives. Adding reclaimed rubber to un-vulcanized rubber to produce rubber products will not change the properties of rubber products, but also save raw materials of rubber and carbon black, and even improve some properties of rubber products.

After years of technical development, “high-temperature and high-pressure dynamic devulcanization” has become the main method for rubber reclamation. For example, the patent CN201210069246.5 proposed an environment-friendly and efficient high-temperature rubber reclamation method. In this method, waste rubber powder, additives and softener were added into the heated devulcanization tank under stirring condition, and the tank temperature was 230 °C and the working time was 4 hours. Then the devulcanized rubber was refined in a large open mill and then cooled for more than 27 hours under 28 °C to obtain reclaimed rubber. The patent CN201510470919.1 proposed a method for preparing environmentally friendly reclaimed rubber by two-stage devulcanization. The first stage was high-temperature devulcanization in devulcanization tank and the second stage was low-temperature devulcanization in the mixer and open mill.

The patent CN201310402782.7 disclosed a novel disc extruder for mixing trace materials, which mainly includes extrusion system, transmission system, temperature control system and receiving system. The extrusion system mainly included feeder, driving shaft, screw block, barrel, rotating plate and fixed plate. The rotating plate was connected with the motor of the transmission system through a reducer and the fixed plate is fixed on the barrel by welding. In this way, the relative rotation of the rotating plate and the fixed plate produces strong shearing force, which was further enhanced by the convex edge on the surface of the rotating plate. All these parts form the mixing system of the rotating plate and the fixed plate. Moreover, the rotating plate and the screw block were installed alternately. With this design, materials could be mixed many times through the conveying of screw groove on the side surface of the rotating plate. The invention applied the principle of high-efficiency shearing blending of grinding disc, and was suitable for high-efficiency and high-uniformity blending of trace materials.

According to the devulcanization mechanism, the high-temperature and high-pressure dynamic devulcanization belongs to chemical reclamation, that is, the activator infiltrates into the waste rubber with the aid of softener under high temperature and reacts with the waste rubber, thus destroying the crosslinking network of the waste rubber and restoring it to a linear and processable polymer chain structure. However, the infiltration process of the activator into the waste rubber needs a long time of high temperature and high pressure, which leads to high energy consumption and low efficiency and causes the process to be non-continuous. Moreover, the long-time high-temperature oxidative cracking increases the probability of main-chain fracture and shortens the rubber molecular chain, decreasing the quality of the uniformity of rubber reclamation, which is not conducive to rubber reclamation. In addition, the condition of high temperature and high pressure causes serious environmental pollution and security risks.

SUMMARY OF THE INVENTION In view of the above problems, the invention proposes a high-efficiency and continuous waste rubber reclaiming equipment, which is realized by adopting the following technical scheme: The invention relates to a high-efficiency continuous waste rubber reclaiming equipment, which includes a high-temperature and high-speed mixing device, a constant temperature storage hopper, a first-stage constant temperature quantitatively metering and conveying device, a thermomechanical chemical decoupling system, a second-stage constant temperature quantitatively metering and conveying device, a low-temperature plasticizing and molding system, a shaping device, a driving system, a transmission system, a cooling system, a heating system and a frame.

Preferably, the high-temperature and high-speed mixing device is fixed on the frame, the discharge port of the high-temperature and high-speed mixing device is connected with the feeding port of the constant temperature storage hopper, the discharge port of the constant temperature storage hopper is connected with the feeding port of the first-stage constant temperature quantitatively metering and conveying device, the discharge port of the first-stage constant temperature quantitatively metering and conveying device is connected with the feeding port of the thermomechanical chemical decoupling system, the discharge port of the thermomechanical chemical decoupling system is connected with the feeding port of the low- temperature plasticizing and molding system through the second-stage constant temperature quantitatively metering and conveying device, and the discharge port of the low-temperature plasticizing and molding system is connected with the shaping device; the thermomechanical chemical decoupling system includes a screw, a barrel, a die, shearing teeth and sealing gaskets.

Preferably, the barrel is fixed on the frame; the barrel is provided with square holes along the circumference direction, and the shearing teeth are inserted into the square holes and fixed; the space between the shearing teeth and the barrel is sealed by sealing gaskets; the shearing teeth are fan-shaped, and the heads of the shearing teeth are set into the barrel; and the end of the barrel is fixedly connected with the die; the screw is located in the internal cavity formed by the barrel and the head, and is fixedly connected with the transmission system, and the screw can rotate in the cavity of the barrel.

Preferably, the screw is divided into three sections: the front compressing section, the middle strong shearing section and the end conveying section; the screw edge of the screw in the strong shearing section is the shearing rib, which is formed by cutting the screw edge along the circumferential direction; the annular space with no screw edge in the middle strong shearing section corresponds to the part position of the shearing teeth penetrating into the barrel; the gaps between the bottom surface of the shearing teeth and the surface of the screw root, the side surface of the shearing teeth and the side surface of the shearing rib, and the gap between the top surface of the shearing rib and the inner surface of the barrel form strong shearing regions.

Preferably, the invention relates to a high-efficiency continuous waste rubber reclaiming equipment, in which the shearing teeth can be designed in different forms according to the shearing capacity, such as one or more combinations of rectangular shearing teeth, arc-shaped shearing teeth, corrugated shearing teeth, scattered point shearing teeth, etc., and each type of the shearing teeth can be combined and used according to the needs.

Preferably, the invention relates to a high-efficiency continuous waste rubber reclaiming equipment, in which the number of the shearing teeth is designed according to the required strength of the shearing force; the number of the shearing teeth in a circle along the circumference of the barrel is 2 to 4, and the number of groups along the axial direction of the barrel is at least 8 groups; the shearing teeth at different circumferential positions can be designed with different types and sizes, and the shearing teeth at different axial positions can be designed with different types, sizes and numbers; and the shearing rib of the screw should be adjusted accordingly.

Preferably, the invention relates to a high-efficiency continuous waste rubber reclaiming equipment, in which the angle ratio (8 / 360 x number of the shearing teeth) of the shearing teeth along the circumferential direction should be designed according to the strength of the shearing teeth and barrel and the shearing capacity of the shearing teeth, and the angle ratio should be 30% - 70%.

Preferably, the invention relates to a high-efficiency continuous waste rubber reclaiming equipment, in which the gaps between the side surface of the shearing teeth and the side surface of the shearing rib of the screw is designed according to the required shearing strength, which can be 0.15 - 1.0 mm; the gaps between the bottom surface of the shearing teeth and the surface of the screw root of the screw is designed according to the required shearing strength, which can be 0.15 - 1.0 mm.

Preferably, the invention relates to a high-efficiency continuous waste rubber reclaiming equipment, in which the low-temperature plasticizing and molding system adopts the same strong shearing design as the thermomechanical chemical decoupling system, and its screw and shearing teeth can adopt different structures and sizes from those of the thermomechanical chemical decoupling system according to the strength requirement of the shearing force field.

Preferably, the shearing teeth have a stepped fan-shaped surface; the upper side surface of the shearing teeth forms a stepped surface; the side surface is a T-shaped surface; the whole body is a combination of annular tile and stepped fan body.

The technical scheme of the invention has at least the following advantages and beneficial effects:

1. The invention designs different structures of the shearing teeth and the number of groups, screw and whole machine structure, realizes controllable decoupling of the crosslinking network of the waste rubber, avoids chain breaking of rubber molecular main chain, and thus can obviously improve the quality of reclaimed rubber.

2. The invention makes full use of the synergistic effect of heat and mechanical force in the devulcanization process of waste rubber, greatly improves the strength of the force field for mechanical dynamic decoupling, strengthens the mechanical shearing effect, improves the reclaiming efficiency and reduces the energy consumption.

3. The invention realizes the continuous production of waste rubber reclamation and reduces the non-uniformity of the reclaiming effect of the traditional high-temperature and high-pressure dynamic devulcanization.

4. The reclaiming process following this invention is completely enclosed, and the action time at high temperature is short; the low temperature plasticizing process adopts a forced cooling system to control the temperature at about 5 - 10 °C, thus there is no cracking gas generated and no environmental pollution problem.

5. The invention combines the thermomechanical chemical decoupling process with the low- temperature plasticizing process, which improves the efficiency of waste rubber decoupling and plasticizing, omits the refining process in which multiple mills are utilized and high energy consumptions are generated, and improves the quality of rubber plasticizing.

6. The invention is able to realize high-quality and environment-friendly reclamation of different kinds of waste rubber through designing the structure of the screw and shearing teeth and adjusting the strength of shearing force field and the decoupling plasticization process.

7. In the invention, the matching region of the shearing rib and shearing teeth is taken as the shearing area, which can expand the shearing area on the one hand, and enhance the torque force that the screw can bear and thus realize decoupling of waste rubber particles with high strength on the other hand.

8. In this invention, the shearing teeth go deep into the root of the screw groove and wide 5 thread and deep screw groove are adopted, forming an inward shearing zone, which can bear larger torque compared with the traditional technique.

DESCRIPTION OF FIGURES Fig. 1 is a schematic diagram of a high-efficiency and continuous waste rubber reclaiming equipment.

Fig. 2 is a schematic diagram of the shearing teeth structure of a high-efficiency and continuous waste rubber reclaiming equipment.

Fig. 3 is a side sectional view of a high-efficiency and continuous waste rubber reclaiming equipment.

Fig. 4 is the circumferential expansion diagram of the shearing teeth and screw ribs of a high- efficiency and continuous waste rubber reclaiming equipment.

Fig. 5 shows different forms of shearing teeth of a high-efficiency and continuous waste rubber reclaiming equipment: (a) rectangular shearing teeth; (b) arc shearing teeth; (c) corrugated shearing teeth; (d) scattered shearing teeth.

Fig. 6 shows the matching diagram of the shearing teeth and barrel of a high-efficiency and continuous waste rubber reclaiming equipment.

1. High-temperature and high-speed mixing device; 2. Constant temperature storage hopper;

3. First-stage constant temperature quantitatively metering and conveying device; 4. Driving system; 5. Transmission system; 6. Frame; 7. Thermomechanical chemical decoupling system;

8. Cooling system; 9. Barrel; 10. Screw; 11. Heating system; 12. Shearing rib; 13. Shearing teeth;

14. Sealing gasket; 15. Front compressing section; 16. Middle strong shearing section; 17. End conveying section; 18. Die; 19. Second-stage constant temperature quantitatively metering and conveying device; 20. Low-temperature plasticizing and molding system; 21. Shaping device; 22. Surface of the screw root; 23. Bottom surface of the shearing teeth; 24. Inner surface of the barrel;

25. Top surface of the shearing rib; 26. Side surface of the shearing rib; 27. Side surface of the shearing teeth; 28. Rectangular shearing teeth; 29. Arc shearing teeth; 30. Corrugated shearing teeth; 31. Scattered shearing teeth; 32. T-shaped surface; 33. Upper side surface of the shearing teeth.

DESCRIPTION OF PREFERRED EMBODIMENTS The present invention is described in combination with the attached drawings and specific embodiments.

In order to make the purpose, technical scheme and advantages of the embodiment of the invention clearer, the technical scheme in the embodiment of the invention will be described clearly and completely in combination with the attached figures. Obviously, the described embodiments are part of the embodiments of the present invention, not all of them.

Therefore, the following detailed descriptions of the embodiments of the invention is not intended to limit the scope of the invention claimed to be protected, but merely represents parts of the embodiments of the invention. Based on the displayed embodiments of the invention, all other embodiments obtained by ordinary technicians in the art without creative labor belong to the scope of protection of the invention.

It should be noted that similar labels and letters denote similar items in the following figures. Therefore, once an item is defined in one of the figures, there is no need to further define and interpret it in subsequent figures.

In the description of the invention, it needs to be explained that the orientation or position relationship indicated by the term, named ‘center’, ‘top’, ‘bottom’, ‘left’, ‘right’, ‘vertical’, ‘horizontal’, ‘inside’ and ‘outside’, and ‘back’, is based on the orientation or position relationship shown in the attached drawings, or is the orientation or position relationship normally placed when the product of the invention is used. Such terms are only for the convenience of describing the invention and simplifying the description, rather than indicating or implying that the device or element in question must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the invention.

It should also be noted that in the description of the present invention, the terms ‘set’, ‘Install’, ‘connect’, and ‘connect’ should be understood in a broad sense unless otherwise specified and limited. For examples, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or an internal connection between two components. For those skilled in the art, the specific meaning of the above terms in the invention can be understood according to the specific situation.

As shown in Fig. 1-8, the present invention, a high-efficiency continuous waste rubber reclaiming equipment, includes a high-temperature and high-speed mixing device 1, a constant temperature storage hopper 2, a first-stage constant temperature quantitatively metering and conveying device 3, a thermomechanical chemical decoupling system 7, a second-stage constant temperature quantitatively metering and conveying device 19, a low-temperature plasticizing and molding system 20, a shaping device 21, a driving system 4, a transmission system 5, a cooling system 8, a heating system 11 and a frame 6.

The high-temperature and high-speed mixing device 1 is fixed on the frame 6, the discharge port of the high-temperature and high-speed mixing device 1 is connected with the feeding port of the constant temperature storage hopper 2, the discharge port of the constant temperature storage hopper 2 is connected with the feeding port of the first-stage constant temperature quantitatively metering and conveying device 3, the discharge port of the first-stage constant temperature quantitatively metering and conveying device 3 is connected with the feeding port of the thermomechanical chemical decoupling system 7.

The discharge port of the thermomechanical chemical decoupling system 7 is connected with the feeding port of the low-temperature plasticizing and molding system 20 through the second-stage constant temperature quantitatively metering and conveying device 19, and the discharge port of the low-temperature plasticizing and molding system 20 is connected with the shaping device 21.

The thermomechanical chemical decoupling system 7 includes screw 10, barrel 9, die 18, shearing teeth 13, sealing gasket 14, etc. The barrel 9 is fixed on the frame 6; the barrel 9 is provided with square holes along the circumference direction, and the shearing teeth 13 are inserted into the square holes and fixed; the space between the shearing teeth 13 and the barrel 9 is sealed by sealing gaskets 14; The shearing teeth 13 are fan-shaped.

Furtherly as shown in Fig. 2, the heads of the shearing teeth 13 is set into the barrel 9; and the end of the barrel 9 is fixedly connected with the die 18; the screw 10 is located in the internal cavity formed by the barrel 9 and the die 18, and is fixedly connected with the transmission system 5, and the screw 10 can rotate in the cavity of the barrel 9.

The screw 10 is divided into three sections: the front compressing section 15, the middle strong shearing section 16 and the end conveying section 17; the screw edge of the screw 10 in the strong shearing section 16 is the shearing rib 12, which is formed by cutting the screw edge along the circumferential direction; the annular space with no screw edge in the middle strong shearing section corresponds to the part position of the shearing teeth 13 penetrating into the barrel 9.

Furtherly, the gaps between the bottom surface of the shearing teeth 23 and the surface of the screw root 22, between the side surface of the shearing teeth 27 and the side surface of the shearing rib 26, and between the top surface of the shearing rib 25 and the inner surface of the barrel 24 form strong shearing regions.

As a preferred embodiment of the present invention, the shearing teeth 13 can be designed in different forms according to the shearing capacity, such as one or more combinations of rectangular shearing teeth 28, arc-shaped shearing teeth 29, corrugated shearing teeth 30, scattered point shearing teeth 31, etc., as shown in Fig. 4, and each type of the shearing teeth 13 can be combined and used according to the needs.

As a preferred embodiment of the present invention, the number of the shearing teeth 13 is designed according to the required strength of the shearing force; the number of the shearing teeth 13 in a circle along the circumference of the barrel 9 is 2 to 4, and the number of groups along the axial direction of the barrel 9 is at least 8; the shearing teeth 13 at different circumferential positions can be designed with different types and sizes, and the shearing teeth 13 at different axial positions can be designed with different types, sizes and numbers; and the shearing rib (12) of the screw (10) should be adjusted accordingly.

As a preferred embodiment of the present invention, the angle ratio (6 / 360 x number of the shearing teeth 13) of the shearing teeth 13 along the circumferential direction should be designed according to the strength of the shearing teeth and barrel and the shearing capacity of the shearing teeth 13, and the angle ratio should be 30% - 70%. As a preferred embodiment of the present invention, the gaps between the side surface of the shearing teeth 27 and the side surface of the shearing rib 26 of the screw 10 is designed according to the required shearing strength, which can be 0.2 - 1.0 mm; the gaps between the bottom surface of the shearing teeth 23 and the surface of the screw root 22 of the screw is designed according to the required shearing strength, which can be 0.2 - 1.0 mm.

Furtherly, the gaps between the side surface of the shearing teeth 27 and the side surface of the shearing rib 26 of the screw 10 is designed according to the required shearing strength, which can be 0.15 - 1.0 mm; the gaps between the bottom surface of the shearing teeth 23 and the surface of the screw root 22 of the screw is designed according to the required shearing strength, which can be 0.15- 1.0 mm.

As a preferred embodiment of the present invention, the low-temperature plasticizing and molding system 20 adopts the same strong shearing design as the thermomechanical chemical decoupling system 7, and its screw 10 and shearing teeth 13 can adopt different structures and sizes from those of the thermomechanical chemical decoupling system 7 according to the strength requirement of the shearing force field.

As a preferred embodiment of the present invention, the shearing teeth 13 have a stepped fan-shaped surface; the upper side surface of the shearing teeth 33 forms a stepped surface; the side surface 32 is a T-shaped surface; the whole body is a combination of annular tile and stepped fan body.

The embodiment of the invention also relates to a high-efficiency and continuous waste rubber reclaiming method: 1) Firstly, the prepared waste rubber material, softener and activator are added into the high- temperature and high-speed mixing device 1. The materials are mixed with high rotating speed in the high-temperature and high-speed mixing device 1 at 240-280°C for 30-40 min, pre-heating the materials and forcing the materials to be mixed adequately, so as to prepare for the subsequent decoupling process. 2) Secondly, after the mixing process is completed, the materials are discharged from the discharge port of the high-temperature and high-speed mixing device 1 and enter the constant temperature storage hopper 2; and then they are transported via the first-stage constant temperature quantitatively metering and conveying device 3 to the thermomechanical chemical decoupling system 7.

3) Thirdly, the temperature of the barrel 9 is controlled in the variation of 240-280 °C and the rotating speed of the screw is set to 40-60r/min; the materials in the thermomechanical chemical decoupling system 7 are transported to the middle strong shearing section 16 under the action of the screw 10; in this area, the gaps between the bottom surface of the shearing teeth 23 and the surface of the screw root 22, between the side surface of the shearing teeth 27 and the side surface of the shearing rib 26, and between the Top surface of the shearing rib 25 and the inner surface of the barrel 24 form strong shearing field; under the action of heat, strong shearing force and additives, waste rubbers are decoupled efficiently.

4) Finally, the waste rubbers in the thermomechanical chemical decoupling system 7 are transported via the second-stage constant temperature quantitatively metering and conveying device 19 to the low-temperature plasticizing and molding system 20 and experience low- temperature plasticizing process; the cooling system 8 forces the temperature to be 5-10°C; the strong shearing force in the low-temperature plasticizing and molding system 20 realizes shearing, extrusion, entanglement and plasticization of the rubber materials and then the rubber materials are extruded in sheet via the shaping device 21.

As a preferred embodiment of the invention, it should be noted that in the production process, the working efficiency of the high-temperature and high-speed mixing device 1 should match with those of the subsequent thermomechanical chemical decoupling process and low-temperature plasticizing and molding process, so as to ensure that there is no material shortage in the constant temperature storage hopper 2 and thus realize the continuous production of reclaimed rubber.

The invention provides a high-efficiency and continuous waste rubber reclaiming equipment, which realizes the continuous production of reclaimed rubber, reduces the problem of uneven devulcanization effect of the traditional high-temperature and high-pressure dynamic devulcanization method, makes full use of the synergistic effect of heat and mechanical force in the rubber devulcanization process, improves the reclamation efficiency, reduces energy consumption, and can significantly improve the quality of reclaimed rubber.

The above embodiments are only used to illustrate and not limit the technical scheme of the invention. Any modification or partial replacement without departing from the spirit of the invention shall be included in the scope of the claims of the invention.

Claims

-10 - CONCLUSIONS

A highly efficient and continuously operating waste rubber recovery device, characterized in that the device comprises: a mixing device (1) operating at high temperature and at high speed, a storage reservoir (2) at constant temperature, a first-stage device ( 3) for quantitative metering and transporting at constant temperature, a thermomechanical-chemical decoupling system (7), a second stage device (19) for quantitative metering and transporting at constant temperature, a low temperature plasticizing and molding system (20) a molding device (21), a driving system (4), a transmission system (5), a cooling system (8), a heating system (11), and a frame (6); wherein the high temperature and high speed mixing device (1) is mounted on the frame (6), the discharge port of the high temperature and high speed mixing device (1) is connected to the supply port of the storage reservoir (2) at constant temperature, wherein the discharge port of the constant temperature storage reservoir (2) is connected to the supply port of the first-step device (3) for quantitative metering and transport at constant temperature, the discharge port of the first-step device (3 ) for quantitative metering and transport at constant temperature is connected to the supply port of the thermomechanical-chemical decoupling system (7); and wherein the discharge port of the thermomechanical-chemical decoupling system (7) is connected to the supply port of the plasticizing and molding system (20) at low temperature through the second-step device (19) for quantitative metering and transporting at constant temperature, and wherein the low temperature discharge port of the plasticizing and molding system (20) is connected to the molding device (21); and wherein the thermomechanical-chemical decoupling system (7) comprises a screw (10), a barrel (9), a die (18), shear teeth (13), and sealing gaskets (14); the barrel (9) being mounted on the frame (6); wherein the barrel (9) is provided with square holes along the circumferential direction, and the shear teeth (13) are provided in the square holes and fixed; where the space between the shear teeth (13) and the barrel (9 is sealed by

-11 - sealing gaskets (14); and wherein the shear teeth (14) are fan-shaped.

Highly efficient and continuously operating waste rubber recovery equipment, according to claim 1, characterized in that : the heads of the shear teeth (13) are arranged in the barrel (9); and the end of the barrel (9) is fixedly connected to the die (18); wherein the screw (10) is located in the internal hollow space formed by the barrel (9) and the die (18), and is fixedly connected to the gear system (5), and wherein the screw (10) can rotate in the hollow space of the barrel (9).

High-efficiency and continuously operating waste rubber recovery equipment, according to claim 2, characterized in that : the screw (10) is divided into three sections: the front compression section (15), the middle section (16) with a high degree of shear, and the rear as conveying section (17); the helix edge of the screw (10) in the middle section (16) having the high shear rate is the shear rib (12), the latter being formed by cutting the helix edge along the circumferential direction; wherein the helix-less annular space in the middle section (16) with the high shear rate corresponds to the position of the shear teeth (13) projecting into the barrel (9).

A highly efficient and continuously operating waste rubber recovery equipment, according to claim 2, characterized in that : the gaps or gaps between the lower surface of the shear teeth (23) and the surface of the core (22) of the screw, between the lateral surface of the shear teeth (27) and the inner surface of the shear rib (26), and between the upper surface of the shear rib (25) and the inner surface of the barrel (24) form areas of high shear.

Highly efficient and continuously operating waste rubber recovery equipment, according to claim 2, characterized in that : the shear teeth (13) can be designed with different shapes according to the

12 - shear capacity, such as one or more combinations of rectangular shear teeth (28), arcuate shear teeth (29), corrugated shear teeth (30), shear teeth (31) with staggered tips, wherein any type of the shear teeth (13) can be combined and be used according to requirements.

High-efficiency and continuously operating waste rubber recovery equipment, according to claim 2, characterized in that : the number of shear teeth (13) is determined as a function of the required strength of the shear forces; wherein the number of shear teeth (13) in a circle along the circumference of the barrel (9) is between 2 and 4, and the number of groups in the axial direction of the barrel (9) is at least equal to 8; wherein the shear teeth (13) may be designed at different positions along the circumference with different types and sizes, and wherein the shear teeth (13) may be designed at different axial positions with different types, sizes, and numbers; and wherein the shear rib (12) of the screw (10) is adjusted accordingly.

High-efficiency and continuously operating waste rubber recovery equipment, according to claim 4, characterized in that the angular ratio (8/360 x number of shear teeth (13)) of the shear teeth (13) along the circumferential direction are designed in accordance with the strength of the shear teeth and of the barrel, and of the shear capacity of the shear teeth (13), the angular ratio being in the range of 30% to 70%.

High-efficiency and continuously operating waste rubber recovery equipment, according to claim 4, characterized in that : the gaps or gaps between the side surface of the shear teeth (27) and the side surface of the shear rib (26) of the screw (10) are designed conform to the required shear forces, the size thereof being 0.2 mm to 1.0 mm, the gaps or gaps between the lower surface of the shear teeth (23) and the surface of the core (22) of the screw (10) are designed in accordance with the requirement

-13 - shear forces, the size thereof being 0.2 mm to 1.0 mm.

A highly efficient and continuously operating waste rubber recovery equipment according to claim 4, characterized in that : the low temperature plasticizing and molding system (20) exhibits the same high shear design as the thermomechanical-chemical decoupling system (7) , and the screw (10) and its shear teeth (13) may have different structures and dimensions from those of the thermomechanical-chemical decoupling system (7), depending on the strength requirements of the shear field; the shear teeth (13) having a stepped fan-shaped surface; the upper side surface of the shear teeth (33) forming a stepped surface; wherein the side surface (32) is a T-shaped surface; and wherein the complete body is a combination of annular tile and stepped fan body.

10. A highly efficient and continuous waste rubber recovery process, characterized in that the process comprises the following steps: 1) the prepared waste rubber material, plasticizer, and activator are added to a mixing device (1) operating at high temperature and at high speed and wherein the materials are mixed at a high rotational speed in the mixing device (1) operating at high temperature and at high speed at 240°C to 280° for 30 minutes to 40 minutes, wherein the materials are preheated, and wherein the materials are adequately forcibly mixed to prepare them for the subsequent decoupling process; 2) after the mixing process is finished, the materials are discharged through the discharge port of the mixing device (1) operating at high temperature and high speed, and enter the storage reservoir (2) at constant temperature; wherein the materials are subsequently transported via the first-step constant temperature quantitative metering and transport device (3) to the thermomechanical-chemical decoupling system (7);

-14 - 3) wherein the temperature of the barrel (9) is controlled and set to a value within the range of 240°C to 280°C, and the rotational speed of the screw is set to a value that is is between 40 rpm to 60 rpm; the materials in the thermomechanical-chemical decoupling system (7) are conveyed to the middle section (16) having the high shear rate under the action of the screw (10); wherein in this zone the gaps or gaps between the lower surface of the shear teeth (23) and the surface of the core (22) of the screw, between the side surface of the shear teeth (27) and the side surface of the shear rib (26), and form a strong shear field between the upper surface of the shear rib (25) and the inner surface of the barrel (24); wherein, under the action of heat, high shear forces, and additives, waste rubber materials are efficiently decoupled; 4) after which finally the waste rubber materials are transported in the thermomechanical-chemical decoupling system (7) via the second-step constant temperature quantitative metering and conveying device (19) to the plasticizing and molding system (20) at low temperature, and are subjected to a low temperature plasticization process; wherein the cooling system (8) ensures that the temperature is forcibly between 5°C and 10°C; wherein the high shear forces in the plasticizing and molding system (20) at low temperature provide the necessary shear, extrusion, swirling, and plasticization of the rubber materials, after which the rubber materials are extruded into a sheet using the molding device (21).