Polymer solution devolatilizer

Abstract

The application discloses a polymer solution devolatilizer, which comprises a first inlet assembly and a second inlet assembly, the outlet ends of the first inlet assembly and the second inlet assembly are respectively provided with a first devolatilization inner part and a second devolatilization inner part, and the outlet faces of the two devolatilization inner parts are provided with a plurality of Venturi type through holes. Low-viscosity polymer solution is fed from the first inlet assembly, is discharged after being promoted to remove volatile components by the first devolatilization inner part, and is deposited on the outer surface of the second devolatilization inner part to form a film, so that the devolatilization time and the mass transfer area are increased. High-viscosity polymer solution is fed from the second inlet assembly, and is promoted to remove volatile components by the second devolatilization inner part. The application can selectively switch the feeding according to the viscosity of the polymer solution, is suitable for devolatilization of polymer solutions with a wide viscosity range, can effectively solve the problem of frequent replacement of devolatilization inner parts during production of different grades with large viscosity difference, guarantees long-period stable operation of the device, and has high devolatilization efficiency and low volatile component content of the obtained polymer.

Description

Technical Field

[0001] This invention belongs to the field of polymer material production and processing technology, and specifically relates to the field of polymer technology. In particular, this invention relates to a polymer solution devolatilizer. Background Technology

[0002] With the widespread application of polymer materials in the automotive industry, photovoltaic modules, and food packaging, polymer materials are increasingly becoming important materials. Polyolefin elastomers (POEs) are widely used in production and daily life due to their unique random copolymer structure and excellent physical properties. In the process of preparing POE using solution polymerization, the polymer system after reaction termination typically contains 60-90 wt% volatile components, including unreacted ethylene monomers, α-olefin comonomers (such as α-butene, α-hexene, and α-octene), and C6-C12 alkane solvents. These residues not only reduce the mechanical properties of the material but may also release volatile organic compounds (VOCs) that are harmful to human health during use.

[0003] When the volatile content in a polymer solution is extremely low or the system viscosity is excessively high, traditional methods typically employ extrusion for devolatilization. However, at high temperatures, POE exhibits significant elastic properties, placing stringent demands on the performance of extrusion equipment and resulting in high energy consumption. Considering the unique physical properties of POE and its devolatilization process requirements, the drop-strip static devolatilizer demonstrates superior applicability. This device forces POE into the devolatilizer through a die, forming a drop strip. During the drop process, volatiles within the melt migrate to the melt-environment interface and are ultimately removed. However, this device still has significant drawbacks: the viscosity range of different grades of polyolefin elastomers is extremely wide, and a single set of equipment cannot meet the devolatilization requirements of all grades. When producing different grades of polyolefin elastomers, it is necessary to replace the devolatilization internal components, causing production shutdowns and significantly increasing production costs. Furthermore, frequent replacement of internal components leads to wear and tear on parts, shortening the service life of the devolatilization device. CN116983691A proposes using a movable orifice plate to make the device suitable for devolatilization of polymers with different viscosities. However, this method is difficult to implement, and the movable orifice plate has problems such as safety hazards and short service life.

[0004] Therefore, there is an urgent need to develop a continuous, safe, and efficient devolatilization device and method that is suitable for devolatilization of polyolefin elastomers with a wide viscosity range. This device should meet the quality and safety requirements of high-end polyolefin elastomer products using only one set of equipment without changing internal components. Summary of the Invention

[0005] The purpose of this invention is to provide a polymer solution devolatilizer, which is suitable for devolatilization of polymer solutions with a wide viscosity range. It can effectively solve the problem of frequent replacement of devolatilization internals when switching production grades with large viscosity differences, ensure long-term stable operation of the device, and has high devolatilization efficiency, resulting in low volatile content of the polymer.

[0006] To achieve the aforementioned technical objective, the present invention provides a polymer solution devolatilizer, characterized in that: the devolatilizer includes a cavity, a first polymer solution inlet assembly, a second polymer solution inlet assembly, an exhaust port, a devolatilization aid injection port assembly, and a polymer outlet; the cavity is provided with a jacket for introducing a heat medium, including but not limited to heat transfer oil and high-pressure steam, to regulate the temperature within the cavity; the outlet end of the first polymer solution inlet assembly is provided with a first devolatilization inner component; the first devolatilization inner component is located at the top of the cavity, with its outlet facing downwards, and the outlet surface of the first devolatilization inner component has several Venturi-type openings. The second inlet assembly of the polymer solution has a second devolatilization inner component at its outlet end, which is located directly below the first devolatilization inner component. The second devolatilization inner component has a downward-facing opening and an expanded diameter design. The outer surface of the second devolatilization inner component is an inclined surface, and its outlet surface has several Venturi-type through holes. The devolatilization aid injection port assembly is located on the side of the cavity, and its outlet position is located below the second devolatilization inner component. The polymer outlet is located at the bottom of the cavity and is used to discharge the devolatilized polymer. The exhaust port is located at the top of the cavity and is used to discharge the volatiles removed from the polymer solution.

[0007] In some preferred embodiments of the present invention, the overall shape of the first devolatilization inner component can be disc-shaped, square, or triangular, and its cross-sectional area is 20% to 60% of the cross-sectional area of ​​the cavity. The main body of the cavity is cylindrical, and the upper and lower ends are covered with ellipsoidal cavity caps. The cross-sectional area of ​​the cavity is the cross-sectional area of ​​the cylindrical main body.

[0008] In some preferred embodiments of the present invention, the overall external shape is a frustum with a taper of 30° to 150°; the outer surface of the frustum is a smooth surface or has protrusions in the shape of serrations, steps, or waves.

[0009] In some preferred embodiments of the present invention, the maximum cross-sectional area of ​​the second devolatilization inner component is 30% to 80% of the cross-sectional area of ​​the cavity, and is 1 to 3 times the cross-sectional area of ​​the first devolatilization inner component, so that the polymer solution or melt discharged from the first devolatilization inner component falls onto the outer surface of the second devolatilization inner component to form a film.

[0010] In some preferred embodiments of the present invention, the distance between the first devolatilization inner member and the second devolatilization inner member is 0.2 to 1 times the diameter of the cavity.

[0011] In some preferred embodiments of the present invention, the Venturi aperture ratio of the first devolatilization inner component is 0.1% to 30%, and the Venturi aperture ratio of the second devolatilization inner component is 0.5% to 40%. The aperture ratio of the second devolatilization inner component is 1 to 6 times that of the first devolatilization inner component.

[0012] In some preferred embodiments of the present invention, the inlet shape of the Venturi-type through-holes of the first devolatilization inner member and the second devolatilization inner member is circular, elliptical or rectangular, and is evenly distributed on the outlet surface of the respective devolatilization inner member.

[0013] In some preferred embodiments of the present invention, the tapered angle of the contraction section of the Venturi-type through hole provided in the first devouring inner component is 10° to 60°, and the tapered angle of the expansion section is 5° to 30°; the tapered angle of the contraction section of the Venturi-type through hole provided in the second devouring inner component is 5° to 30°, and the tapered angle of the expansion section is 2° to 15°.

[0014] In some preferred embodiments of the present invention, the devolatilization aid injected through the devolatilization aid injection port is N2, water vapor, methane, ethane, or a mixture of the above gases; the viscosity of the polymer solution introduced through the first polymer solution inlet component is 0.1-500 Pa·s, and the viscosity of the polymer solution introduced through the second polymer solution inlet component is 500-20000 Pa·s.

[0015] The present invention also provides a method for polymer solution devolatilization using the aforementioned polymer solution devolatilizer, comprising the following steps:

[0016] A heat transfer medium is introduced into the cavity to regulate the cavity temperature to the required devolatilization temperature; the viscosity of the polymer solution to be devolatilized is monitored in real time, and the polymer solution to be devolatilized is switched through the pipeline according to the viscosity of the polymer solution to allow the polymer solution to enter the first inlet component or the second inlet component of the polymer solution.

[0017] Heat transfer oil is introduced into the cavity to regulate the cavity temperature to the required devolatilization temperature; the viscosity of the polymer solution to be devolatilized is monitored in real time, and the polymer solution to be devolatilized is switched through the pipeline according to the viscosity of the polymer solution to allow the polymer solution to enter the first polymer solution inlet component or the second polymer solution inlet component.

[0018] Low-viscosity polymer solutions with a viscosity of 0.1-500 Pa·s enter the first inlet component of the polymer solution, while high-viscosity polymer solutions with a viscosity of 500-20000 Pa·s enter the second inlet component. The Venturi constriction section of the devolatilization internal accelerates the material flow rate, breaks and refines the bubbles, and accelerates the diffusion of volatiles into the gas phase. The expansion section causes a sharp drop in material flow rate and a rapid decrease in static pressure, forming a local negative pressure, which lowers the boiling point of volatile components, making them easier to vaporize and escape. After the low-viscosity polymer solution exits from the first devolatilization internal, it falls onto the outer surface of the second devolatilization internal and forms a film, increasing the devolatilization time and mass transfer area of ​​the polymer solution. The film falls along the edge of the second devolatilization internal to the bottom of the cavity.

[0019] During the devolatilization process, devolatilization aid is continuously injected into the devolatilization aid injection port assembly. The devolatilization aid enhances the devolatilization process by reducing the partial pressure of volatiles and providing an inert gas environment. The volatile components released during the devolatilization process are discharged from the exhaust port, and the devolatilized polymer melt is discharged from the polymer discharge port.

[0020] In some preferred embodiments of the present invention, the polymer solution before entering the devolatilizer has its real-time viscosity detected by a viscosity detection device. The viscosity detection device transmits the viscosity information to the control module, which compares the viscosity information with a detection threshold (which can be set to 500 Pa·s). Based on the comparison result, the control module automatically controls the opening and closing of the pipeline valves. For example, when the viscosity is lower than the detection threshold, the pipeline valve of the first inlet component is opened, and the pipeline valve of the second inlet component is closed; when the real-time viscosity is higher than the detection threshold, the pipeline valve of the second inlet component is opened, and the pipeline valve of the first inlet component is closed. This achieves automatic switching of the feed pipeline based on the feed properties. According to a preferred embodiment of the present invention, the pipeline valves of the first inlet component and the second inlet component can be integrated into a three-way valve. The control module selects the outlet branch of the three-way valve based on the viscosity information to achieve feed pipeline switching.

[0021] The present invention has the following outstanding gain effects:

[0022] (1) The low viscosity polymer is fed from the first devouring internal. It has low viscosity and good flowability. Since the cross-sectional area of ​​the second devouring internal is larger, the polymer solution falls onto the inclined surface of the second devouring internal. The protrusion of the inclined surface causes the low viscosity polymer, which is difficult to continuously drop, to form a film on its surface, which greatly increases the devouring mass transfer time and mass transfer surface area, and significantly improves the devouring efficiency.

[0023] (2) High-viscosity polymers can be continuously and stably dropped, but they have poor flowability, take a long time to pass through the devolatilization distributor, and have high pressure on the distributor, which poses a safety hazard. By switching the feed from the second devolatilization internal with a larger opening ratio through the valve, the pressure on the distributor can be effectively reduced, and the formation of more dropped strands can also help increase the devolatilization mass transfer surface area, thus significantly improving the devolatilization efficiency.

[0024] (3) The contraction section of the Venturi orifice will increase the material flow rate and the pressure will drop sharply. Through the cavitation effect, it will promote the supercritical nucleation of volatiles and form more bubble nuclei, thereby improving the removal efficiency.

[0025] Using the above-mentioned device can increase the devolatilization time of low-viscosity polymers and reduce the distributor pressure of high-viscosity polymers. It is suitable for polymers with a wide viscosity range, ensures the long-term stable operation of the device, and greatly improves the nucleation, growth and collapse speed of volatile bubbles, thereby improving the devolatilization efficiency. The volatile removal efficiency in polymers can reach more than 90% through static devolatilization. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the polymer solution devolatilizer with a multilayer distributor according to the present invention;

[0027] Figure 2 This is a schematic diagram of the first devoured internal component;

[0028] Figure 3 This is a schematic diagram of the second devouring internal component. Detailed Implementation

[0029] To facilitate understanding of the present invention, further description is provided below. However, the present invention can be implemented in many different forms. The following embodiments are for illustrative purposes only and should not be considered as limiting the scope of the invention. Unless otherwise specified, specific conditions in the embodiments are performed under conventional conditions or conditions recommended by the manufacturer. Reagents or instruments used, unless otherwise specified, are all commercially available conventional products.

[0030] The following methods were used to test the properties of the polymers produced in the examples described:

[0031] Headspace gas chromatography is used to test the residual solvent content of polyolefin elastomers.

[0032] like Figure 1As shown, this invention provides a polymer solution devolatilization device, comprising: a cavity 1, a first polymer solution inlet assembly 2, a second polymer solution inlet assembly 3, an exhaust port 4, a devolatilization aid injection port assembly 5, and a polymer outlet 6. The first polymer solution inlet assembly 2 has a first devolatilization inner element 7 at its material outlet end, located at the top of the cavity 1; the second polymer solution inlet assembly 3 has a second devolatilization inner element 8 at its material outlet end, located below the first devolatilization inner element; the exhaust port 4 is located at the top of the cavity 1; the devolatilization aid injection port assembly 5 enters the cavity 1 from the side, and its material outlet is located below the second devolatilization inner element 8; the polymer outlet 6 is located at the bottom of the cavity 1. In a specific embodiment of this invention, the polymer solution feed line is divided into two branches, respectively connected to the first polymer solution inlet assembly 2 and the second polymer solution inlet assembly 3. Valves 9 are installed on the two feed lines to switch the feed path of polymer solutions of different viscosities.

[0033] like Figure 2 The diagram shown is an optional structural schematic of the first devolatilization inner component 7 of the present invention. In this embodiment, the overall external shape of the first devolatilization inner component is a disc shape (see...). Figure 2 (Lower left part), the outlet surface of the first extraction internal component is set downwards, and multiple Venturi-type through holes are opened on the outlet surface (see...) Figure 2 (Top left section), the opening ratio of the Venturi-type through-hole of the first devoured internal component is 0.1% to 5%; the inlet shape of the Venturi-type through-hole is circular, elliptical, or rectangular, and is evenly distributed on the outlet surface; the cone angle of the contraction section of the Venturi-type through-hole is 10° to 60°, and the cone angle of the expansion section is 5° to 30° (see...). Figure 2 (Right side); The Venturi constriction section of the first devolatilization internal increases the material flow rate, breaks and refines bubbles, increases the mass transfer area, and accelerates the diffusion of volatiles into the gas phase; the expansion section causes a sharp drop in flow rate and a rapid decrease in static pressure, forming a local negative pressure, which significantly lowers the boiling point of volatile components, making them easier to vaporize and escape. In an embodiment of the present invention, the outlet surface of the first devolatilization internal faces downward, and its cross-sectional area is 20% to 60% of the cavity cross-sectional area.

[0034] like Figure 3 The diagram shown is an optional structural schematic of the second devouring inner member 8 of the present invention. The opening of the second devouring inner member faces downward and is designed with an expanded diameter. Its outer surface is an inclined surface, and its outlet surface has several Venturi-type through holes (see...). Figure 3 (Upper left part); the Venturi-type through-hole opening ratio of the second devouring internal component is 0.5% to 10%. In this embodiment, the overall external shape of the second devouring internal component is a frustum shape (see upper left part); Figure 3(Lower left part), with a taper of 30° to 150°; the outer surface of the frustum is provided with protrusions in the shape of sawtooth, stepped, or wavy. The maximum cross-sectional area of ​​the second devouring inner part is 30% to 80% of the cross-sectional area of ​​the cavity, and is 1 to 3 times the cross-sectional area of ​​the first devouring inner part. The inlet shape of the Venturi-type through hole is circular, elliptical, or rectangular, and is evenly distributed on the outlet surface. The cone angle of the contraction section of the Venturi-type through hole is 5° to 30°, and the cone angle of the expansion section is 2° to 15° (see...). Figure 3 (Right side). The venturi through-hole contraction and expansion sections of the second devolatilization internals form a dynamic devolatilization environment with low-pressure excitation and enhanced mass transfer, promoting the removal of volatiles.

[0035] Example 1:

[0036] In this embodiment, the flow rate of the polyolefin elastomer entering the devolatilizer is 150 kg / h, with a solid content of 90 wt%. The cavity is heated by 240°C hot oil, the outlet temperature of the polyolefin elastomer solution is 220°C, the operating temperature of the devolatilizer is 230°C, the operating pressure is 0.01 MPaG, the bottom of the cavity is inverted conical with a cone angle of 60°, the cavity height is 200 cm, and the cavity cross-sectional area is 800 cm². 2 .

[0037] The first devolatilization inner component is disc-shaped with a cross-sectional area of ​​200 cm². 2 A total of 30 circular Venturi through holes are made, each with a diameter of 0.5 cm and a spacing of 0.8 cm, evenly distributed in a square. The cone angle of the Venturi contraction section is 10° and the cone angle of the expansion section is 5°.

[0038] The second devolatilization inner component is frustum-shaped with an 80° taper. Protrusions with a serrated shape are provided on both sides of the inclined surface. The cross-sectional area of ​​the second devolatilization inner component is 300 cm². 2 A total of 50 circular Venturi through holes are made, each with a diameter of 0.6 cm and a spacing of 0.8 cm, evenly distributed in an equilateral triangle. The cone angle of the Venturi contraction section is 10° and the cone angle of the expansion section is 8°.

[0039] The distance between the first devolatilization inner component and the second devolatilization inner component is 80cm, and N2 is injected through the devolatilization aid injection port.

[0040] When the viscosity of the polymer solution is 100 Pa·s, the polymer solution (volatile content 10 wt%) is switched by the valve to enter the cavity from the first devolatilization internal. The inlet pressure of the first devolatilization internal is 1.2 MPa, and the VOC content in the polymer at the outlet is 280 ppm.

[0041] When the viscosity of the polymer solution is 1000 Pa·s, the polymer solution (volatile content 10 wt%) is switched by the valve to enter the chamber from the second devolatilization internal. The inlet pressure of the second devolatilization internal is 1.8 MPa, and the VOC content in the polymer at the outlet is 200 ppm.

[0042] Example 2:

[0043] In this embodiment, the flow rate of the polyolefin elastomer entering the devolatilizer is 150 kg / h, with a solid content of 90 wt%. The cavity is heated by 240°C hot oil, the outlet temperature of the polyolefin elastomer solution is 220°C, the operating temperature of the devolatilizer is 230°C, the operating pressure is 0.01 MPaG, the bottom of the cavity is inverted conical with a cone angle of 60°, the cavity height is 200 cm, and the cavity cross-sectional area is 800 cm². 2 .

[0044] The first devolatilization inner component is disc-shaped with a cross-sectional area of ​​200 cm². 2 A total of 30 circular Venturi through holes are made, each with a diameter of 0.5 cm and a spacing of 0.8 cm, arranged in an equilateral triangle. The cone angle of the Venturi contraction section is 10° and the cone angle of the expansion section is 5°.

[0045] The second devolatilization inner component is frustum-shaped with an 80° taper. Protrusions with a serrated shape are provided on both sides of the inclined surface. The cross-sectional area of ​​the second devolatilization inner component is 300 cm². 2 A total of 50 circular Venturi through holes are made, each with a diameter of 0.6 cm and a spacing of 0.8 cm, arranged in an equilateral triangle. The cone angle of the Venturi contraction section is 10° and the cone angle of the expansion section is 8°.

[0046] The distance between the first devolatilization inner component and the second devolatilization inner component is 70cm, and CO2 is injected through the devolatilization aid injection port;

[0047] When the viscosity of the polymer solution is 100 Pa·s, the polymer solution (volatile content 10 wt%) is switched by the valve to enter the devolatilization tank from the first devolatilization internal. The inlet pressure of the first devolatilization internal is 1.2 MPa, and the VOC content in the polymer at the outlet is 350 ppm.

[0048] When the viscosity of the polymer solution is 1000 Pa·s, the polymer solution (volatile content 10 wt%) is switched through the valve to enter the devolatilization tank from the second devolatilization internal. The inlet pressure of the second devolatilization internal is 1.8 MPa, and the VOC content in the polymer at the outlet is 300 ppm.

[0049] Comparative Example 1.1:

[0050] In this embodiment, the flow rate of the polyolefin elastomer entering the devolatilizer is 150 kg / h, with a solid content of 90 wt%. The chamber is heated by 240°C hot oil, the outlet temperature of the polyolefin elastomer solution is 230°C, the operating temperature of the devolatilizer is 240°C, the operating pressure is 0.01 MPaG, the bottom of the chamber is inverted conical with a cone angle of 60°, the chamber height is 200 cm, and the chamber cross-sectional area is 700 cm². 2 .

[0051] The devolatilization inner component is disc-shaped with a cross-sectional area of ​​200 cm². 2 Twenty circular through holes, each 0.5 cm in diameter, are arranged in an equilateral triangle with a spacing of 0.8 cm between them.

[0052] The polymer solution has a viscosity of 1000 Pa·s. The polymer solution (volatile content 10 wt%) enters the devolatilizer from the devolatilization internals. During the experiment, the inlet pressure of the devolatilization internals is >8 MPa, and the safe inlet pressure of the devolatilization internals is 8 MPa. The experiment is then stopped.

[0053] Comparative Example 1.2:

[0054] In this embodiment, the flow rate of the polyolefin elastomer entering the devolatilizer is 150 kg / h, with a solid content of 90 wt%. The chamber is heated by 240°C hot oil, the outlet temperature of the polyolefin elastomer solution is 230°C, the operating temperature of the devolatilizer is 240°C, the operating pressure is 0.01 MPaG, the bottom of the chamber is inverted conical with a cone angle of 60°, the chamber height is 200 cm, and the chamber cross-sectional area is 700 cm². 2 .

[0055] The devolatilization inner component is disc-shaped with a cross-sectional area of ​​200 cm². 2 There are 40 circular through holes, each with a diameter of 0.5 cm and a spacing of 0.8 cm, arranged in an equilateral triangle.

[0056] The polymer solution has a viscosity of 100 Pa·s. The polymer solution (volatile content 10 wt%) enters the devolatilizer from the devolatilization internals. The inlet pressure of the devolatilization internals is 0.1 MPa, and the VOC content of the melt at the outlet is 45023 ppm.

[0057] Comparative Example 2:

[0058] In this embodiment, the flow rate of the polyolefin elastomer entering the devolatilizer is 150 kg / h, with a solid content of 90 wt%. The chamber is heated by 240°C hot oil, the outlet temperature of the polyolefin elastomer solution is 230°C, the operating temperature of the devolatilizer is 240°C, the operating pressure is 0.01 MPaG, the bottom of the chamber is inverted conical with a cone angle of 60°, the chamber height is 200 cm, and the cross-sectional area of ​​the chamber is 700 cm². 2 .

[0059] The first devolatilization inner component is disc-shaped with a cross-sectional area of ​​200 cm². 2 There are 30 circular through holes, each with a diameter of 0.5 cm and a spacing of 0.8 cm, arranged in an equilateral triangle.

[0060] The second devolatilization inner component is frustum-shaped with an 80° taper. Protrusions with a serrated shape are provided on both sides of the inclined surface. The cross-sectional area of ​​the second devolatilization inner component is 300 cm². 2 There are 50 circular through holes, each with a diameter of 0.6 cm and a spacing of 0.8 cm, arranged in an equilateral triangle.

[0061] The distance between the first devolatilization inner component and the second devolatilization inner component is 80cm, and CO2 is injected through the devolatilization aid injection port.

[0062] When the viscosity of the polymer solution is 100 Pa·s, the polymer solution (volatile content 10 wt%) is switched by the valve to enter the devolatilization tank from the first devolatilization internal. The inlet pressure of the devolatilization internal is 1.3 MPa, and the VOC content in the polymer at the outlet is 2684 ppm.

[0063] When the viscosity of the polymer solution is 1000 Pa·s, the polymer solution (volatile content 10 wt%) is switched through the valve to enter the devolatilization tank from the second devolatilization internal. The inlet pressure of the devolatilization internal is 1.8 MPa, and the VOC content in the polymer at the outlet is 1589 ppm.

[0064] The differences between the apparatus and results of each embodiment and the comparative example are shown in Table 1.

[0065] Table 1. Differences between the apparatus and results of the embodiments and comparative examples.

[0066]

[0067] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A polymer solution devolatilizer, characterized in that: The devolatilizer includes a cavity, a first polymer solution inlet assembly, a second polymer solution inlet assembly, an exhaust port, a devolatilizer injection port assembly, and a polymer outlet port; The cavity is equipped with a jacket for introducing a heat transfer medium, including but not limited to heat transfer oil and high-pressure steam, to regulate the temperature inside the cavity. The outlet end of the first inlet assembly of the polymer solution is provided with a first devolatilization inner element; the first devolatilization inner element is located at the top of the cavity, with its outlet facing downwards, and the outlet surface of the first devolatilization inner element is provided with a plurality of Venturi-type through holes. The outlet end of the second inlet assembly of the polymer solution is provided with a second devolatilization inner element. The second devolatilization inner element is located directly below the first devolatilization inner element. Its opening faces downward and has an enlarged diameter design. The outer surface of the second devolatilization inner element is an inclined surface, and its outlet surface has several Venturi-type through holes. The devolatilization aid injection port assembly is located on the side of the cavity, and its outlet is located below the second devolatilization inner component; The polymer outlet is located at the bottom of the cavity and is used to discharge the devolatilized polymer; The exhaust port is located at the top of the cavity and is used to discharge volatiles removed from the polymer solution; The cross-sectional area of ​​the outlet surface of the first devouring inner component is 20% to 60% of the cross-sectional area of ​​the cavity; the maximum cross-sectional area of ​​the second devouring inner component is 30% to 80% of the cross-sectional area of ​​the cavity, and is 1 to 3 times the cross-sectional area of ​​the first devouring inner component; the overall external shape of the second devouring inner component is a frustum shape with a taper of 30° to 150°; the outer surface of the frustum is a smooth surface or has protrusions in the shape of sawtooth, stepped or wavy.

2. The polymer solution devolatilizer according to claim 1, characterized in that, The distance between the first devouring inner component and the second devouring inner component is 0.2 to 1 times the diameter of the cavity.

3. The polymer solution devolatilizer according to claim 1, characterized in that, The Venturi-type through-hole opening ratio of the first devouring internal component is 0.1%~30%, and the Venturi-type through-hole opening ratio of the second devouring internal component is 0.5%~40%.

4. The polymer solution devolatilizer according to claim 1 or 3, characterized in that, The opening ratio of the second devolatilization inner component is 1 to 6 times that of the opening ratio of the first devolatilization inner component.

5. The polymer solution devolatilizer according to claim 1 or 3, characterized in that, The venturi-type through-holes of the first and second devouring components have circular, elliptical, or rectangular inlet shapes and are evenly distributed on the outlet surfaces of the respective devouring components.

6. The polymer solution devolatilizer according to claim 5, characterized in that, The first devouring inner component has a Venturi-type through hole with a contraction section cone angle of 10°~60° and an expansion section cone angle of 5°~30°; the second devouring inner component has a Venturi-type through hole with a contraction section cone angle of 5°~30° and an expansion section cone angle of 2°~15°.

7. The polymer solution devolatilizer according to claim 1, characterized in that, The devolatilization aid injected through the devolatilization aid injection port is N2, water vapor, methane, ethane, or a mixture of the above gases; the viscosity of the polymer solution introduced through the first polymer solution inlet component is 0.1-500 Pa·s, and the viscosity of the polymer solution introduced through the second polymer solution inlet component is 500-20000 Pa·s.

8. A polymer solution devolatilization method based on the polymer solution devolatilizer of claim 1, characterized in that, Includes the following steps: A heat transfer medium is introduced into the cavity to regulate the cavity temperature to the required devolatilization temperature; the viscosity of the polymer solution to be devolatilized is monitored in real time, and the polymer solution to be devolatilized is switched through the pipeline according to the viscosity of the polymer solution to allow the polymer solution to enter the first inlet component or the second inlet component of the polymer solution. Low-viscosity polymer solutions with a viscosity of 0.1-500 Pa·s enter the first inlet component of the polymer solution, while high-viscosity polymer solutions with a viscosity of 500-20000 Pa·s enter the second inlet component. The Venturi constriction section of the devolatilization internal accelerates the material flow rate, breaks and refines the bubbles, and accelerates the diffusion of volatiles into the gas phase. The expansion section causes a sharp drop in material flow rate and a rapid decrease in static pressure, forming a local negative pressure, which lowers the boiling point of volatile components, making them easier to vaporize and escape. After the low-viscosity polymer solution exits from the first devolatilization internal, it falls onto the outer surface of the second devolatilization internal and forms a film, increasing the devolatilization time and mass transfer area of ​​the polymer solution. The film falls along the edge of the second devolatilization internal to the bottom of the cavity. During the devolatilization process, devolatilization aid is continuously injected into the devolatilization aid injection port assembly. The devolatilization aid enhances the devolatilization process by reducing the partial pressure of volatiles and providing an inert gas environment. The volatile components released during the devolatilization process are discharged from the exhaust port, and the devolatilized polymer melt is discharged from the polymer discharge port.

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