Polymer solution devolatilization system

Abstract

The utility model discloses a polymer solution devolatilization system and belongs to the technical field of devolatilization equipment. The polymer solution devolatilization system comprises a polymer solution storage tank, a first condenser, a first gas-liquid separation tank, a first vacuum pump, a delivery pump, a heater, a preheater, a devolatilization device, a discharge pump, a second condenser, a second gas-liquid separation tank and a second vacuum pump. According to the utility model, the volatile component outlet of the polymer solution storage tank is sequentially connected with the first condenser and the first gas-liquid separation tank to form an auxiliary devolatilization route; a discharge port of a polymer solution storage tank is sequentially connected with a heater, a preheater and a devolatilization device, and a volatile component outlet of the devolatilization device is sequentially connected with a second condenser and a second gas-liquid separation tank, so that a main devolatilization route is formed; due to the design of the auxiliary devolatilization route, the devolatilization efficiency of the system can be effectively improved, the load of a devolatilization device in the main devolatilization route can be effectively reduced, and the devolatilization effect of the system is improved.

Description

Technical Field

[0001] This utility model relates to the field of devolatilization equipment technology, specifically to a polymer solution devolatilization system. Background Technology

[0002] Solution polymerization is one of the main processes for producing high molecular weight polymers. Solution polymerization involves the polymerization reaction of monomers and initiators (or catalysts) dissolved in a suitable solvent. Therefore, the polymer solution obtained from the polymerization reaction contains not only polymers but also a large amount of organic solvents; the mass percentage of solvent in the polymer solution can reach over 80%. In the solution polymerization process, the devolatilization stage is the main stage for removing volatile components (mainly solvents) from the polymer solution, and the degree of devolatilization directly affects the properties of the polymer after extrusion molding.

[0003] Existing technologies typically involve directly introducing the polymer solution into a heater for heating, and then introducing it into a devolatilizer for devolatilization. This method results in poor devolatilization effect, low devolatilization efficiency, and a high volatile content in the polymer product.

[0004] Therefore, it is essential to design a polymer solution devolatilization system with good devolatilization effect and high devolatilization efficiency. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a polymer solution devolatilization system with good devolatilization effect and high devolatilization efficiency.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0007] A polymer solution devolatilization system includes a polymer solution storage tank, a first condenser, a first gas-liquid separator, a first vacuum pump, a transfer pump, a heater, a preheater, a devolatilizer, a discharge pump, a second condenser, a second gas-liquid separator, and a second vacuum pump. The volatile matter outlet of the polymer solution storage tank is connected to the inlet of the first condenser via a pipeline, the outlet of the first condenser is connected to the inlet of the first gas-liquid separator via a pipeline, and the gas phase outlet of the first gas-liquid separator is connected to the first vacuum pump via a pipeline. The polymer solution storage tank is equipped with a stirrer and a heating mechanism. The outlet of the solution storage tank is connected to the inlet of the delivery pump via a pipeline; the outlet of the delivery pump is connected to the inlet of the heater via a pipeline; the outlet of the heater is connected to the inlet of the preheater via a pipeline; the outlet of the preheater is connected to the inlet of the devolatilizer; the outlet of the devolatilizer is connected to the discharge pump; the volatile matter outlet of the devolatilizer is connected to the inlet of the second condenser via a pipeline; the outlet of the second condenser is connected to the inlet of the second gas-liquid separator via a pipeline; and the gas phase outlet of the second gas-liquid separator is connected to the second vacuum pump via a pipeline.

[0008] Preferably, the stirrer includes a stirring paddle, a rotating shaft, and a drive motor. The stirring paddle is located inside the polymer solution storage tank and is mounted on the rotating shaft. The rotating shaft passes through the polymer solution storage tank and is connected to the output end of the drive motor. The rotating shaft is rotatably engaged with the polymer solution storage tank.

[0009] Preferably, the heating mechanism includes a heating jacket disposed outside the polymerization solution storage tank, the upper part of the heating jacket is provided with a heat medium outlet, and the lower part of the heating jacket is provided with a heat medium inlet.

[0010] Preferably, the liquid phase outlet of the first gas-liquid separator is connected to a first devolatilization storage tank via a pipeline, and the bottom outlet of the first devolatilization storage tank is connected to a first drain pipe, and a first drain valve is provided on the first drain pipe.

[0011] Preferably, the liquid phase outlet of the second gas-liquid separator is connected to a second devolatilization storage tank via a pipeline, and the bottom outlet of the second devolatilization storage tank is connected to a second drain pipe, and a second drain valve is provided on the second drain pipe.

[0012] Preferably, the inlet of the polymer solution storage tank is connected to an inlet pipe, and an inlet valve is provided on the inlet pipe.

[0013] Preferably, a first regulating valve is provided on the pipeline between the volatile outlet of the polymer solution storage tank and the inlet of the first condenser.

[0014] Preferably, a second regulating valve is provided on the pipe between the outlet of the heater and the inlet of the preheater.

[0015] Preferably, a third regulating valve is provided on the pipe between the volatile outlet of the degasser and the inlet of the second condenser.

[0016] Preferably, the discharge pump is connected to an extruder via a pipeline.

[0017] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0018] This invention forms an auxiliary devolatilization route by sequentially connecting the volatile outlet of the polymer solution storage tank to a first condenser and a first gas-liquid separator; and forms a main devolatilization route by sequentially connecting the outlet of the polymer solution storage tank to a heater, a preheater, and a devolatilizer, and sequentially connecting the volatile outlet of the devolatilizer to a second condenser and a second gas-liquid separator. The design of the auxiliary devolatilization route can effectively improve the devolatilization efficiency of the system and effectively reduce the load on the devolatilizer in the main devolatilization route, thereby improving the devolatilization effect of the system. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the polymer solution devolatilization system provided by this utility model.

[0020] In the diagram, 1-polymer solution storage tank, 2-first condenser, 3-first gas-liquid separator, 4-first vacuum pump, 5-transfer pump, 6-heater, 7-preheater, 8-devourer, 9-discharge pump, 10-second condenser, 11-second gas-liquid separator, 12-second vacuum pump, 13-stirrer, 14-heating mechanism, 15-first devourer storage tank, 16-first drain valve, 17-second devourer storage tank, 18-second drain valve, 19-inlet valve, 20-first regulating valve, 21-second regulating valve, 22-third regulating valve, 23-extruder. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0022] Please see Figure 1This utility model provides a polymer solution devolatilization system, including a polymer solution storage tank 1, a first condenser 2, a first gas-liquid separator 3, a first vacuum pump 4, a transfer pump 5, a heater 6, a preheater 7, a devolatilizer 8, a discharge pump 9, a second condenser 10, a second gas-liquid separator 11, and a second vacuum pump 12. The top of the polymer solution storage tank 1 is provided with a volatile matter outlet and a liquid inlet, and the bottom of the polymer solution storage tank 1 is provided with a discharge outlet. The volatile matter outlet of the polymer solution storage tank 1 is connected to the inlet of the first condenser 2 via a pipe, and the outlet of the first condenser 2 is connected to the inlet of the first gas-liquid separator 3 via a pipe. The gas phase outlet of the first gas-liquid separator 3 is connected to the first vacuum pump. 4. The polymer solution storage tank 1 is equipped with a stirrer 13 and a heating mechanism 14 via pipeline connections. The outlet of the polymer solution storage tank 1 is connected to the inlet of the delivery pump 5 via a pipeline. The outlet of the delivery pump 5 is connected to the inlet of the heater 6 via a pipeline. The outlet of the heater 6 is connected to the inlet of the preheater 7 via a pipeline. The outlet of the preheater 7 is connected to the inlet of the devolatilizer 8 via a pipeline. The outlet of the devolatilizer 8 is connected to the discharge pump 9 via a pipeline. The volatile matter outlet of the devolatilizer 8 is connected to the inlet of the second condenser 10 via a pipeline. The outlet of the second condenser 10 is connected to the inlet of the second gas-liquid separator 11 via a pipeline. The gas phase outlet of the second gas-liquid separator 11 is connected to the second vacuum pump 12 via a pipeline.

[0023] This invention forms an auxiliary devolatilization route by sequentially connecting the volatile outlet of the polymer solution storage tank 1 to the first condenser 2 and the first gas-liquid separator 3; and forms the main devolatilization route by sequentially connecting the outlet of the polymer solution storage tank 1 to the heater 6, the preheater 7 and the devolatilizer 8, and sequentially connecting the volatile outlet of the devolatilizer 8 to the second condenser 10 and the second gas-liquid separator 11. The design of the auxiliary devolatilization route can effectively improve the devolatilization efficiency of the system and effectively reduce the load on the devolatilizer in the main devolatilization route, thereby improving the devolatilization effect of the system.

[0024] In one embodiment, the stirrer 13 includes a stirring paddle, a rotating shaft, and a drive motor. The stirring paddle is located inside the polymer solution storage tank 1 and is mounted on the rotating shaft. The rotating shaft passes through the tank cover of the polymer solution storage tank 1 and is connected to the output end of the drive motor. The rotating shaft is rotatably engaged with the tank cover of the polymer solution storage tank 1.

[0025] In one embodiment, the heating mechanism 14 includes a heating jacket disposed outside the polymerization solution storage tank, with a heat medium outlet at the upper part of the heating jacket and a heat medium inlet at the lower part of the heating jacket.

[0026] In one embodiment, the liquid phase outlet of the first gas-liquid separator 3 is connected to a first devolatilization storage tank 15 via a pipeline, and the bottom outlet of the first devolatilization storage tank 15 is connected to a first drain pipe, and a first drain valve 16 is provided on the first drain pipe.

[0027] In one embodiment, the liquid phase outlet of the second gas-liquid separator 11 is connected to a second devolatilization storage tank 17 via a pipeline, and the bottom outlet of the second devolatilization storage tank 17 is connected to a second drain pipe, on which a second drain valve 18 is provided.

[0028] In one embodiment, the inlet of the polymer solution storage tank 1 is connected to an inlet pipe, and an inlet valve 19 is provided on the inlet pipe.

[0029] In one embodiment, a first regulating valve 20 is provided on the pipeline between the volatile outlet of the polymer solution storage tank 1 and the inlet of the first condenser 2.

[0030] In one embodiment, a second regulating valve 21 is provided on the pipe between the outlet of the heater 6 and the inlet of the preheater 7.

[0031] In one embodiment, a third regulating valve 22 is provided on the pipe between the volatile outlet of the devolatilizer 8 and the inlet of the second condenser 10.

[0032] In one embodiment, the discharge pump 9 is connected to the extruder 23 via a pipe.

[0033] In this invention, the first regulating valve 20, the second regulating valve 21, and the third regulating valve 22 can be pressure regulating valves. This invention, through the cooperation of the first regulating valve 20 and the first vacuum pump 4, discharges the devolatilized gas and regulates the pressure within the polymer solution storage tank 1; this invention, through the cooperation of the second regulating valve 21, regulates the pressure and flow rate within its pipeline; and through the cooperation of the third regulating valve 22 and the second vacuum pump 12, discharges the devolatilized gas and regulates the pressure within the devolatilizer 8.

[0034] In one embodiment, the devolatilizer 8 is a strip-type devolatilizer.

[0035] The working principle of the system provided by this invention for devolatilizing polymer solutions is as follows:

[0036] Open the feed valve 19, and the polymer solution is fed into the polymer solution storage tank 1 through the feed pipe. The polymer solution in the polymer solution storage tank 1 is stirred and heated by the stirrer 13 and the heating structure 14. Start the first vacuum pump 4, and adjust the gas flow in the pipeline through the first regulating valve 20 so that the devolatilized gas discharged from the polymer solution storage tank 1 is condensed by the first condenser 2, and then separated by the first gas-liquid separator 3. The separated gas phase component is discharged by the first vacuum pump 4, and the separated liquid phase is collected in the first devolatilized liquid storage tank 15.

[0037] Open the second regulating valve 21 and the third regulating valve 22, start the delivery pump 5 and the second vacuum pump 12. The polymer solution in the polymer solution storage tank 1 flows through the heater 6, the preheater 7 and the devolatilizer 8 in sequence. After devolatilization in the devolatilizer 8, the discharged devolatilized gas is condensed by the second condenser 10, and then separated by the second gas-liquid separator 11. The separated gas phase is discharged by the second vacuum pump 12, and the separated liquid phase is collected in the second deflaking liquid storage tank 17.

[0038] The devolatilization liquid in the first devolatilization liquid storage tank 15 can be discharged as waste liquid through the first discharge valve 16, and the devolatilization liquid in the second devolatilization liquid storage tank 17 can be discharged as waste liquid through the second discharge valve 18.

[0039] The present invention will be further described in detail below with reference to the embodiments.

[0040] Example 1

[0041] This embodiment uses, as follows: Figure 1 The system shown performs devolatilization. The system includes a polymer solution storage tank 1, a first condenser 2, a first gas-liquid separator 3, a first vacuum pump 4, a transfer pump 5, a heater 6, a preheater 7, a devolatilizer 8, a discharge pump 9, a second condenser 10, a second gas-liquid separator 11, and a second vacuum pump 12. The top of the polymer solution storage tank 1 is provided with a volatile matter outlet and a liquid inlet, and the bottom of the polymer solution storage tank 1 is provided with a discharge outlet. The volatile matter outlet of the polymer solution storage tank 1 is connected to the inlet of the first condenser 2 via a pipe, and the outlet of the first condenser 2 is connected to the inlet of the first gas-liquid separator 3 via a pipe. The gas phase outlet of the first gas-liquid separator 3 is connected to the first vacuum pump 4 via a pipe. The polymer solution storage tank 1 is equipped with a stirrer 13 and a heating mechanism 14. The outlet of the polymer solution storage tank 1 is connected to the inlet of the delivery pump 5 through a pipeline. The outlet of the delivery pump 5 is connected to the inlet of the heater 6 through a pipeline. The outlet of the heater 6 is connected to the inlet of the preheater 7 through a pipeline. The outlet of the preheater 7 is connected to the inlet of the devolatilizer 8. The outlet of the devolatilizer 8 is connected to the discharge pump 9. The volatile matter outlet of the devolatilizer 8 is connected to the inlet of the second condenser 10 through a pipeline. The outlet of the second condenser 10 is connected to the inlet of the second gas-liquid separator 11 through a pipeline. The gas phase outlet of the second gas-liquid separator 11 is connected to the second vacuum pump 12 through a pipeline.

[0042] The stirrer 13 includes a stirring paddle, a rotating shaft, and a drive motor. The stirring paddle is located inside the polymer solution storage tank 1 and is mounted on the rotating shaft. The rotating shaft passes through the tank cover of the polymer solution storage tank 1 and is connected to the output end of the drive motor. The rotating shaft is rotatably engaged with the tank cover of the polymer solution storage tank 1. The heating mechanism 14 includes a heating jacket disposed on the outside of the polymer solution storage tank. The upper part of the heating jacket is provided with a heat medium outlet, and the lower part of the heating jacket is provided with a heat medium inlet.

[0043] The liquid phase outlet of the first gas-liquid separator 3 is connected to the first devolatilization storage tank 15 via a pipeline. The bottom outlet of the first devolatilization storage tank 15 is connected to the first drain pipe, and the first drain pipe is equipped with the first drain valve 16. The liquid phase outlet of the second gas-liquid separator 11 is connected to the second devolatilization storage tank 17 via a pipeline. The bottom outlet of the second devolatilization storage tank 17 is connected to the second drain pipe, and the second drain pipe is equipped with the second drain valve 18.

[0044] The inlet of the polymer solution storage tank 1 is connected to an inlet pipe, and an inlet valve 19 is installed on the inlet pipe.

[0045] A first regulating valve 20 is installed on the pipeline between the volatile outlet of the polymer solution storage tank 1 and the inlet of the first condenser 2; a second regulating valve 21 is installed on the pipeline between the outlet of the heater 6 and the inlet of the preheater 7; and a third regulating valve 22 is installed on the pipeline between the volatile outlet of the devolatilizer 8 and the inlet of the second condenser 10.

[0046] The first regulating valve 20, the second regulating valve 21, and the third regulating valve 22 are pressure regulating valves.

[0047] The system provided in this embodiment is used for devolatilization. The polymer solution to be devolatilized is a toluene solution of a cyclic olefin copolymer, wherein the solvent mass percentage is approximately 85%. The polymer solution is continuously fed into the polymer solution storage tank 1 for assisted devolatilization. During the assisted devolatilization process, the temperature inside the polymer solution storage tank 1 is controlled at 80-90°C by the heating mechanism 14, and the polymer solution inside the polymer solution storage tank 1 is stirred by the stirrer 13. At the same time, the first vacuum pump 4 is turned on, and the first regulating valve 20 is adjusted to control the pressure inside the polymer solution storage tank 1 at -40 to -50 kPa. The devolatilized gas discharged from the polymer solution storage tank 1 is condensed by the first condenser 2, and then separated into gas and liquid phases by the first gas-liquid separator 3. The gas phase is discharged by the first vacuum pump, and the liquid phase is collected in the devolatilized liquid storage tank 4.

[0048] After assisted devolatilization, the mass percentage of solvent in the polymer solution is reduced to approximately 75 wt%. The polymer solution after assisted devolatilization is fed into heater 6 by transfer pump 5 and heated to the devolatilization temperature of 220-230°C. The heated polymer solution is pressurized to 3 MPa by the pressure regulation of the second regulating valve 22, and then preheated to 230°C by preheater 7 before entering the 230°C devolatilizer 8 for polymer solution devolatilization. During the polymer solution devolatilization process, the second vacuum pump is turned on and the third regulating valve 22 is adjusted to control the pressure of devolatilizer 8 at -10 to 20 kPa. The devolatilized gas discharged from devolatilizer 8 is condensed by the second condenser 10, and then separated into gas and liquid phases by the second gas-liquid separator 11. The gas phase is discharged by the second vacuum pump, and the liquid phase is collected in the second devolatilized liquid storage tank 17. The devolatilized polymer is discharged by discharge pump 9.

[0049] The polymer discharged by discharge pump 9 contains less than 0.05% solvent by mass, and there is no yellowing phenomenon in the polymer discharged by discharge pump 9.

[0050] Comparative Example 1

[0051] The difference between this comparative example and Example 1 is that this comparative example uses the following... Figure 1 When the system shown is performing devolatilization, the first regulating valve 20 and the first vacuum pump 4 are not turned on. The polymer solution is continuously fed into the polymer solution storage tank 1. The temperature in the polymer solution storage tank 1 is controlled at 80-90°C by the heating mechanism 14. Under the action of the delivery pump 5, the polymer solution in the polymer solution storage tank 1 is heated to 220-230°C by the heater 6. After heating, the polymer solution is pressurized to 3MPa by the pressure regulation of the second regulating valve 22. Then, it is preheated to 230°C by the preheater 7 and enters the devolatilizer 8 at 230°C for polymer solution devolatilization. During the polymer solution devolatilization process, the second vacuum pump is turned on and the third regulating valve 22 is adjusted to control the pressure of the devolatilizer 8 at -50 to -60kPa. The devolatilized gas discharged from the devolatilizer 8 is condensed by the second condenser 10 and then separated into gas and liquid phases by the second gas-liquid separator 11. The gas phase is discharged by the second vacuum pump and the liquid phase is collected in the second devolatilized liquid storage tank 17. The devolatilized polymer is discharged by the discharge pump 9.

[0052] The polymer discharged by discharge pump 9 contains approximately 1% solvent by mass, and the polymer discharged by discharge pump 9 exhibits a certain degree of yellowing.

[0053] Compared with Comparative Example 1, Example 1 performed assisted devolatilization before the polymer solution entered the devolatilizer, which reduced the load on the devolatilizer, allowing the pressure of the devolatilizer to be set at a lower vacuum level, or even a slight positive pressure, and the devolatilization effect was better.

[0054] Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first," "second," or "third" may explicitly or implicitly include one or more of that feature.

[0055] In the description of this utility model, it should be understood that the terms "upper", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the system or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model and are not intended to limit the scope of protection of this utility model. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this utility model without departing from the essence and scope of the technical solutions of this utility model.

Claims

1. A polymer solution devolatilization system characterized by, The system comprises a polymer solution storage tank, a first condenser, a first gas-liquid separation tank, a first vacuum pump, a conveying pump, a heater, a preheater, a devolatilizer, a discharge pump, a second condenser, a second gas-liquid separation tank and a second vacuum pump, a volatile outlet of the polymer solution storage tank is connected with an inlet of the first condenser through a pipeline, an outlet of the first condenser is connected with an inlet of the first gas-liquid separation tank through a pipeline, a gas phase outlet of the first gas-liquid separation tank is connected with the first vacuum pump through a pipeline, the polymer solution storage tank is provided with a stirrer and a heating mechanism, a discharge outlet of the polymer solution storage tank is connected with an inlet of the conveying pump through a pipeline, an outlet of the conveying pump is connected with an inlet of the heater through a pipeline, an outlet of the heater is connected with an inlet of the preheater through a pipeline, an outlet of the preheater is connected with a feeding port of the devolatilizer, a discharge outlet of the devolatilizer is connected with the discharge pump, a volatile outlet of the devolatilizer is connected with an inlet of the second condenser through a pipeline, an outlet of the second condenser is connected with a feeding port of the second gas-liquid separation tank through a pipeline, a gas phase outlet of the second gas-liquid separation tank is connected with the second vacuum pump through a pipeline.

2. The polymer solution devolatilization system of claim 1, wherein, The stirrer comprises a stirring paddle, a rotating shaft and a driving motor, the stirring paddle is located in the polymer solution storage tank, the stirring paddle is installed on the rotating shaft, the rotating shaft is connected with an output end of the driving motor after penetrating through the polymer solution storage tank, and the rotating shaft is rotationally matched with the polymer solution storage tank.

3. The polymer solution devolatilization system of claim 1, wherein, The heating mechanism comprises a heating jacket arranged outside the polymer solution storage tank, a hot medium outlet is arranged at an upper portion of the heating jacket, and a hot medium inlet is arranged at a lower portion of the heating jacket.

4. The polymer solution devolatilization system of claim 1, wherein, A first devolatilization liquid storage tank is connected with a liquid phase outlet of the first gas-liquid separation tank through a pipeline, a first liquid discharge pipe is connected with a bottom outlet of the first devolatilization liquid storage tank, and a first liquid discharge valve is arranged on the first liquid discharge pipe.

5. The polymer solution devolatilization system of claim 1, wherein, A second devolatilization liquid storage tank is connected with a liquid phase outlet of the second gas-liquid separation tank through a pipeline, a second liquid discharge pipe is connected with a bottom outlet of the second devolatilization liquid storage tank, and a second liquid discharge valve is arranged on the second liquid discharge pipe.

6. The polymer solution devolatilization system of claim 1, wherein, A liquid inlet pipe is connected with a liquid inlet of the polymer solution storage tank, and a liquid inlet valve is arranged on the liquid inlet pipe.

7. The polymer solution devolatilization system of claim 1, wherein, A first adjusting valve is arranged on a pipeline between the volatile outlet of the polymer solution storage tank and the inlet of the first condenser.

8. The polymer solution devolatilization system of claim 1, wherein, A second adjusting valve is arranged on a pipeline between the outlet of the heater and the inlet of the preheater.

9. The polymer solution devolatilization system of claim 1, wherein, A third adjusting valve is arranged on a pipeline between the volatile outlet of the devolatilizer and the inlet of the second condenser.

10. The polymer solution devolatilization system of claim 1, wherein, The discharge pump is connected with an extruder through a pipeline.

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