High-molecular polymer devolatilization method and device

Abstract

The invention discloses a high-molecular polymer devolatilization method and a high-molecular polymer devolatilization device. According to the devolatilization method, a devolatilization machine is divided into a first devolatilization area, a second devolatilization area and a third devolatilization area, and steam is introduced into a devolatilization machine jacket and a rotor shaft to heat the devolatilization areas in the devolatilization machine; in the devolatilization process, the temperature of each devolatilization area is strictly controlled, the devolatilization temperature of the next unit devolatilization time is dynamically adjusted by obtaining the unit devolatilization time, and the obtained high-viscosity melt is subjected to deep devolatilization after being crushed under the working condition of a thermal medium. According to the method, the energy consumption in the devolatilization process is controlled by strictly regulating and controlling the temperature of each devolatilization area according to the physicochemical property change of a material in the devolatilization process, and the device provided by the invention is provided with an independent closed heating system, so that the contact between a polymer and a heating medium is effectively isolated, and the energy consumption is reduced; and the distributed precise control of the temperature is also realized, the generation of waste liquid and waste gas is thoroughly solved, and the technical purposes of high-efficiency waste-free devolatilization and great reduction of energy consumption are realized.

Description

Technical Field

[0001] The invention relates to a polymer devolatilization method, in particular to a high molecular polymer devolatilization method and device, belonging to the technical field of high molecular polymer devolatilization. Background Art

[0002] The devolatilization technology of high molecular polymers currently mainly adopts the water analysis method of condensation devolatilization. The main process is: add the glue liquid into the condensation kettle, pass superheated steam to heat the third medium water to a certain temperature, and then heat the glue liquid with hot water to remove the reactive monomers and solvents therein, so as to achieve the purpose of water washing method condensation devolatilization. The water washing method of condensation devolatilization requires the liquid medium (water) with low thermal conductivity to be heated as the heat source for heating the glue liquid, and the process flow is long, so the energy consumption is high, resulting in high production costs; it occupies a large area of ​​land and many equipments, resulting in high construction investment; it produces a large amount of waste liquid and waste gas, resulting in high environmental protection costs; it is not suitable for the production of certain products, thus affecting the industrialization process of new products. Therefore, developing a new devolatilization method and device is the only way to effectively solve the above problems. Summary of the invention

[0003] In view of the problems existing in the prior art, the first object of the present invention is to provide a method for devolatilization of a high molecular polymer. The method controls the energy consumption in the devolatilization process by strictly regulating the temperature of each devolatilization zone according to the changes in the physicochemical properties of the material during the devolatilization process. A jacket heating system and a rotor shaft heating system with steam as the heat source are adopted to avoid direct contact between the heating medium and the polymer. Not only the accuracy of temperature control is achieved, but also the generation of waste liquid and waste gas is completely solved, thereby achieving the technical purpose of efficient and waste-free devolatilization while greatly reducing energy consumption.

[0004] The second object of the present invention is to provide a high molecular polymer devolatilization device, which realizes dynamic regulation of the temperature of the devolatilization process by partitioned detection of changes in the physicochemical properties of the polymer. By setting up an independent closed heating system, it not only effectively isolates the contact between the polymer and the heating medium, but also realizes distributed and precise control of the temperature. The device has the advantages of simple structure, stable performance and low cost, and is suitable for large-scale industrial applications.

[0005] In order to achieve the above technical purpose, the present invention provides a high molecular polymer devolatilization device, comprising a devolatilizer (1), a deep devolatilization device and a gas treatment device; a rotor shaft (2) is arranged on the central axis of the long axis of the devolatilizer, and a rotor shaft heating system is arranged inside the rotor shaft for controlling the temperature of the rotor shaft; a first devolatilization area (4), a second devolatilization area (5) and a third devolatilization area (6) are arranged in sequence inside the devolatilizer along the direction of entry of the rotor shaft, a jacket heating system is arranged between the first, second and third devolatilization areas and the devolatilizer shell, and a volatilization channel (3) connected to the gas treatment device is provided in each devolatilization area; a high molecular polymer inlet (11) is provided in the first devolatilization area of ​​the devolatilizer, and a high molecular polymer discharge outlet (12) connected to the deep devolatilization device is provided in the third devolatilization area; a nitrogen inlet (13) is also provided in the first devolatilization area for replacing the air atmosphere in the devolatilizer.

[0006] As a preferred solution, the gas processing device includes a gas-liquid separation tank (71), a first condenser (72), a pre-pump buffer tank (73), a vacuum pump (74), a second condenser (75) and a liquid storage device (8) connected in sequence; the liquid phase component in the pre-pump buffer tank (73) directly enters the liquid storage device through a pipeline, and the gas phase component enters the second condenser through the vacuum pump.

[0007] As a preferred solution, the liquid storage device is also provided with an exhaust port directly connected to the first condenser.

[0008] As a preferred solution, the deep devolatilization device comprises a colloid delivery pump (15), a crushing and separation device (9), a gas-liquid stirring kettle (10) and a delivery pump (14) which are connected in sequence.

[0009] As a preferred solution, the material discharged from the high molecular polymer outlet of the devolatilizer enters the crushing and separation device through a colloid delivery pump for crushing, and the gas-liquid stirring kettle is used to deeply devolatilize the crushed high molecular polymer particles to discharge volatiles and high molecular polymers.

[0010] As a preferred solution, the delivery pump is also directly connected to the crushing and separation device for multiple devolatilization.

[0011] As a preferred solution, the gas-liquid stirring kettle is also provided with an air inlet hole connected to the rotor shaft heating system and the jacket heating system.

[0012] The present invention also provides a method for devolatilizing a high molecular polymer, which is implemented by any of the above-mentioned devices and comprises the following steps:

[0013] S1. The steam is passed into the devolatilizer jacket and the rotor shaft (2) to preheat the devolatilizer (1);

[0014] S2. The polymer is fed from the polymer inlet (11) into the first devolatilization zone of the devolatilizer, and then the second devolatilization zone and the third devolatilization zone are devolatilized;

[0015] S3 obtains the initial viscosity value of the polymer entering the devolatilizer, the viscosity value of the first devolatilization product, the viscosity value of the second devolatilization product and the devolatilization mass (wt). When the initial viscosity value is greater than 0 and the viscosity value of the first devolatilization product is equal to 0, start step S4. When the viscosity value of the first devolatilization product is greater than 0, start step S5.

[0016] S4. According to the initial viscosity value, the first devolatilization product viscosity value and the second devolatilization product viscosity value and the devolatilization mass (wt), the rotor shaft (2) speed and the first devolatilization zone (4), the second devolatilization zone (5) and the third devolatilization zone (6) The devolatilization temperature;

[0017] S5. Obtain the mass of polymer transported per unit time, taking the time from entering the devolatilizer (1) to exiting the devolatilizer (1) as the unit devolatilization time, obtain the initial viscosity value, the viscosity value of the first devolatilization product and the viscosity value of the second devolatilization product and the devolatilization mass (wt) within the unit devolatilization time, and adjust the devolatilization temperatures of the first devolatilization zone (4), the second devolatilization zone (5) and the third devolatilization zone (6) within the next unit devolatilization time;

[0018] S6. The high molecular polymer after devolatilization in the devolatilizer (1) is transported to a crushing and separation device (9) for crushing and separation;

[0019] S7. The polymer particles are deeply devolatilized to obtain the initial viscosity value of the deep devolatilization and the deep devolatilization mass per unit time (wt), and the devolatilization temperature and speed of the gas-liquid stirring reactor are adjusted;

[0020] S8. Outputting the polymer particles after deep devolatilization;

[0021] The devolatilization mass is the mass (wt) of volatiles removed from the polymer, and the deep devolatilization mass (wt) per unit time is the mass (wt) of volatiles removed from the polymer through the gas-liquid stirring kettle per unit time;

[0022] The first devolatilization product is a polymer obtained by devolatilization treatment in the first devolatilization zone;

[0023] The second devolatilization product is a polymer obtained by devolatilization treatment in the second devolatilization zone.

[0024] As a preferred solution, the temperatures of the first, second and third devolatilization zones in S4 are obtained by:

[0025] S4-1. The first devolatilization zone temperature: The first devolatilization zone temperature and the rotor shaft speed are set according to the initial viscosity value;

[0026] S4-2. Temperature of the second and third devolatilization zones: Obtain the viscosity difference between the product of the previous devolatilization zone and the polymers of the first two devolatilization zones, and set the current devolatilization zone temperature.

[0027] As a preferred solution, the temperature ranges of the first, second and third devolatilization zones are from one to five, namely: the first temperature is 80-100°C, the second temperature is 100-120°C; the third temperature is 120-140°C; the fourth temperature is 140-160°C; and the fifth temperature is 160-190°C.

[0028] As a preferred solution, the rotor shaft speed is a high speed or a low speed, and the high speed is Low speed

[0029] As a preferred solution, the temperature of the first devolatilization zone is: when the initial viscosity value is less than or equal to the first viscosity threshold, the devolatilization temperature of the first devolatilization zone (4) is set to a first temperature and the rotor shaft speed is a high speed; otherwise, the devolatilization temperature of the first devolatilization zone (4) is set to a second temperature and the rotor shaft speed is a low speed.

[0030] As a preferred solution, the temperature of the second devolatilization zone is: when the difference between the viscosity value of the first devolatilization product and the initial viscosity value is ≤ the first viscosity difference, if the first devolatilization mass (wt) ≤ the first mass (wt) threshold, the devolatilization temperature of the second devolatilization zone (5) is set to the fourth temperature; if the first mass threshold < the first devolatilization mass (wt) ≤ the second mass threshold, the devolatilization temperature of the second devolatilization zone (5) is set to the third temperature; if the first devolatilization mass (wt) > the second mass threshold, the devolatilization temperature of the second devolatilization zone (5) is set to the second temperature;

[0031] When the first viscosity difference is less than the difference between the first devolatilization product viscosity value and the initial viscosity value and less than or equal to the second viscosity difference, if the first devolatilization mass (wt) is less than or equal to the first mass threshold, the devolatilization temperature of the second devolatilization zone (5) is set to the fifth temperature level; if the first mass threshold is less than the first devolatilization mass (wt) is less than or equal to the second mass threshold, the devolatilization temperature of the second devolatilization zone (5) is set to the fourth temperature level; if the first devolatilization mass (wt) is greater than the second mass threshold, the devolatilization temperature of the second devolatilization zone (5) is set to the third temperature level;

[0032] When the difference between the viscosity value of the first devolatilization product and the initial viscosity value is greater than the second viscosity difference, if the first devolatilization mass (wt) ≤ the first mass threshold, the devolatilization temperature of the second devolatilization zone (5) is set to the sixth temperature level; if the first mass threshold < the first devolatilization mass (wt) ≤ the second mass threshold, the devolatilization temperature of the second devolatilization zone (5) is set to the fifth temperature level; if the first devolatilization mass (wt) > the second mass threshold, the devolatilization temperature of the second devolatilization zone (5) is set to the fourth temperature level.

[0033] As a preferred scheme, the first viscosity difference refers to the difference between the viscosity value of the product in the second devolatilization zone and the viscosity value of the product in the first devolatilization zone, and the second viscosity difference refers to the difference between the viscosity value of the product in the third devolatilization zone and the viscosity value of the product in the first devolatilization zone; the first mass wt% threshold refers to the difference between the mass wt% of the product in the second devolatilization zone and the mass wt% of the product in the first devolatilization zone, and the second mass wt% threshold refers to the difference between the mass wt% of the product in the third devolatilization zone and the mass wt% of the product in the second devolatilization zone.

[0034] In the present invention, the initial viscosity value is the viscosity value of the polymer when it enters the devolatilizer; the first devolatilization product viscosity value is the polymer viscosity value when the polymer passes through the first devolatilization area and the first devolatilization product is obtained for the first time, and is about to enter the second devolatilization area; the second devolatilization product viscosity value is the polymer viscosity value when the polymer passes through the second devolatilization area and the second devolatilization product is obtained, and is about to enter the third devolatilization area; the first devolatilization mass is the mass of volatiles corresponding to the first devolatilization product, which is the actual value achieved; the second devolatilization mass: the mass of volatiles corresponding to the first devolatilization product, which is the actual value achieved; the first mass threshold and the second mass threshold are instrument setting values, which can be adjusted according to actual working conditions, and the first viscosity difference and the second viscosity difference can be set according to the actual polymer composition to be devolatilized, the initial viscosity value, the solute concentration at the time of discharge, and the target solute concentration at the time of discharge. Under common working conditions, the first viscosity difference can be set to 2000mpa·s; the second viscosity difference can be set to 3000mpa·s.

[0035] As a preferred solution, the temperature of the third devolatilization zone is: when the difference between the viscosity value of the second devolatilization product and the viscosity value of the first devolatilization product is ≤ the first viscosity difference, the devolatilization temperature of the third devolatilization zone is set by the difference between the viscosity value of the second devolatilization product and the initial viscosity value and the second devolatilization mass;

[0036] When the difference between the viscosity value of the second devolatilization product and the viscosity value of the first devolatilization product is greater than the first viscosity difference, if the second devolatilization mass (wt) is ≥ the third mass threshold, the devolatilization temperature of the third devolatilization zone (6) is set to a first temperature; if the second devolatilization mass (wt) is less than the third mass threshold, the devolatilization temperature of the third devolatilization zone is set by the difference between the viscosity value of the second devolatilization product and the initial viscosity value and the second devolatilization mass.

[0037] As a preferred solution, the process of setting the devolatilization temperature of the third devolatilization zone by the difference between the viscosity value of the second devolatilization product and the initial viscosity value and the second devolatilization mass (wt) is:

[0038] When the difference between the viscosity value of the second devolatilization product and the initial viscosity value is ≥ the third viscosity difference, if the second devolatilization mass (wt) is ≥ the third mass threshold, the devolatilization temperature of the third devolatilization zone is set to the second temperature; if the second devolatilization mass (wt) is < the third mass threshold, the third devolatilization zone is calculated according to the devolatilization temperature formula;

[0039] When the second viscosity difference is ≤ the difference between the viscosity of the second devolatilization product and the initial viscosity value and < the third viscosity difference, if the second devolatilization mass (wt) is ≥ the third mass threshold, the devolatilization temperature of the third devolatilization zone (6) is set to a first-stage temperature; if the second devolatilization mass (wt) is < the third mass threshold, the devolatilization temperature is calculated according to the devolatilization temperature formula;

[0040] When the difference between the viscosity value of the second devolatilization product and the initial viscosity value is less than the second viscosity difference, if the second devolatilization mass (wt) is ≥ the third mass threshold, the devolatilization temperature of the third devolatilization zone (6) is set to a first temperature; if the second devolatilization mass (wt) is less than the third mass threshold, it is calculated according to the devolatilization temperature formula.

[0041] As a preferred solution, the devolatilization temperature formula is:

[0042] Wherein, T3 is the devolatilization temperature of the third devolatilization zone, T2 is the devolatilization temperature of the second devolatilization zone; M is the total mass of the polymer to be devolatilized; M1 is the first devolatilization mass; and M2 is the second devolatilization mass.

[0043] As a preferred solution, the temperature adjustment of the first, second and third devolatilization zones in S5 is achieved by:

[0044] S5-1. The formula for calculating the unit devolatilization time of the polymer transported per unit time from entering the devolatilizer (1) to discharging the devolatilizer (1) is:

[0045] Where t is the unit devolatilization time, V 聚 is the volume of polymer transported per unit time, S 桶 is the cross-sectional area of ​​the devolatilizer, v 轴 is the propulsion speed of the rotor shaft, d 桶 is the length of the devolatilizer, and k is the volume coefficient of the devolatilizer.

[0046] S5-2 obtain the initial viscosity value, the first devolatilization product viscosity value, the second devolatilization product viscosity value and the devolatilization mass (wt) per unit devolatilization time n times, calculate the average initial viscosity, the average first devolatilization product viscosity, the average second devolatilization product viscosity and the average devolatilization mass (wt);

[0047] S5-3. Obtain the difference between the average viscosity of the first devolatilization product and the average initial viscosity within the current unit devolatilization time, the difference between the average viscosity of the second devolatilization product and the average viscosity of the first devolatilization product, and the average devolatilization mass (wt); when the average devolatilization mass (wt) = the first target devolatilization mass (wt), maintain the temperature set for each area in S4; when the average devolatilization mass (wt) < the first target devolatilization mass (wt), calculate the temperature of each devolatilization area by the unit time devolatilization temperature formula;

[0048] The formula for the devolatilization temperature per unit time is:

[0049] Among them, M 目 is the first target devolatilization mass (wt), is the average devolatilization mass (wt), T 前 is the devolatilization temperature of the devolatilization area within the current unit devolatilization time, T 下 is the devolatilization temperature of the devolatilization zone within the next unit devolatilization time. 下 When the calculated value is greater than the maximum devolatilization temperature that the polymer can withstand, then T 下 Take the maximum devolatilization temperature.

[0050] Compared with the prior art, the beneficial technical effects of the present invention are:

[0051] 1) In the devolatilization method provided by the present invention, the energy consumption in the devolatilization process is controlled by strictly regulating the temperature of each devolatilization zone according to the changes in the physicochemical properties of the material during the devolatilization process. A jacket heating system and a rotor shaft heating system using steam as a heat source are adopted to avoid direct contact between the heating medium and the polymer, which not only achieves the accuracy of temperature control, but also completely solves the generation of waste liquid and waste gas, thereby achieving the technical purpose of efficient and waste-free devolatilization while greatly reducing energy consumption.

[0052] 2) The devolatilization device provided by the present invention realizes dynamic regulation of the temperature of the devolatilization process by detecting the changes in the physicochemical properties of the polymer by partitioning. By setting up an independent closed heating system, it not only effectively isolates the contact between the polymer and the heating medium, but also realizes distributed and precise control of the temperature. The device has the advantages of simple structure, stable performance and low cost, and is suitable for large-scale industrial applications.

[0053] 3) In the technical solution provided by the present invention, the jacket and rotor shaft of the devolatilizer are heated by steam, and then heat exchange is performed with the high molecular polymer, which replaces the need to heat the liquid medium (water) with low thermal conductivity as a heat source for heating the glue liquid, avoiding the problem of high energy consumption and the generation of a large amount of waste liquid and waste gas; according to the viscosity change and devolatilization mass (wt) data of monitoring polymer devolatilization, the jacket temperature of the devolatilizer and the speed of the rotor shaft in the first devolatilization area, the second devolatilization area and the third devolatilization area are dynamically adjusted to improve the devolatilization efficiency. The method and device have the advantages of high devolatilization efficiency, small amount of waste liquid and waste gas, large operation flexibility, short process route, and low investment cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 This is a schematic flow chart of the high molecular polymer devolatilization method provided by the present invention;

[0055] Figure 2 This is a schematic diagram of a high molecular polymer devolatilization device provided by the present invention;

[0056] Figure 2 In the figure, 1-devolatilizer, 2-rotor shaft, 3-volatilization channel, 4-first devolatilization area, 5-second devolatilization area, 6-third devolatilization area, 71-gas-liquid separation tank, 72-first condenser, 73-pre-pump buffer tank, 74-vacuum pump, 75-second condenser, 8-liquid storage device, 9-crushing and separation device, 10-gas-liquid stirring kettle, 11-high molecular polymer inlet, 12-high molecular polymer outlet, 13-nitrogen inlet, 14-delivery pump, 15-colloid delivery pump. DETAILED DESCRIPTION

[0057] The specific implementation scheme of the present invention will be described in detail and clearly in conjunction with the examples below. It is obvious that the described examples are only part of the examples of the present invention, rather than all of the examples. Based on the examples of the present invention, all other examples obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present invention.

[0058] The embodiments provided by the present invention are all implemented by the following devolatilization device: the high molecular polymer devolatilization device comprises a devolatilizer 1, a deep devolatilization device and a gas treatment device; a rotor shaft 2 is arranged on the central axis of the long axis of the devolatilizer, and a rotor shaft heating system is arranged inside the rotor shaft for temperature control of the rotor shaft; a first devolatilization area 4, a second devolatilization area 5 and a third devolatilization area 6 are arranged in sequence inside the devolatilizer along the entry direction of the rotor shaft, a jacket heating system is arranged between the first, second and third devolatilization areas and the devolatilizer shell, and a volatilization channel 3 connected to the gas treatment device is opened in each devolatilization area; a high molecular polymer inlet 11 is opened in the first devolatilization area of ​​the devolatilizer, and a high molecular polymer discharge outlet 12 connected to the deep devolatilization device is opened in the third devolatilization area; a nitrogen inlet 13 is also opened in the first devolatilization area for replacing the air atmosphere in the devolatilizer.

[0059] The rotor shaft heating system, jacket heating system and deep devolatilization heating system are connected to an external steam device to form a circulation heating of steam. The steam temperature can be changed by controlling the external steam heating device. Steam temperature controllers can also be set at the inlet and outlet of the rotor shaft heating system and the jacket heating system to change the steam temperature.

[0060] The gas processing device includes a gas-liquid separation tank 71, a first condenser 72, a pre-pump buffer tank 73, a vacuum pump 74 and a second condenser 75 which are connected in sequence. The first devolatilization area 4, the second devolatilization area 5 and the third devolatilization area 6 are provided with a volatilization channel 3 on the devolatilizer 1 corresponding to the devolatilization area 4, the second devolatilization area 5 and the third devolatilization area 6, which are all connected to the gas-liquid separation tank 71. The outlet of the second condenser 75 is connected to the liquid storage device 8. The volatiles volatilized from the first devolatilization area 4, the second devolatilization area 5 and the third devolatilization area 6 enter the gas-liquid separation tank 71 through the volatilization channel 3, and the trace amount of liquid carried in the volatiles is separated. The gaseous volatiles enter the pre-pump buffer tank 73 after passing through the first condenser 72, and the liquid volatiles are collected in the pre-pump buffer tank 73. The liquid volatiles in the pre-pump buffer tank 73 enter the liquid storage device 8 through the outlet for storage, and the gaseous volatiles enter the second condenser 75 through the vacuum pump 74 for condensation. The condensed liquid volatiles enter the liquid storage device 8 for storage. In the process, a part of non-gaseous volatiles will be carried into the liquid storage device 8, and this part of gaseous volatiles enters the first condenser 72 from the exhaust port of the liquid storage device 8 to be condensed again. The gas-liquid separation tank 71, the first condenser 72, the pre-pump buffer tank 73, the vacuum pump 74, the second condenser 75 and the liquid storage device 8 form a circulating volatile recovery system, and the devolatilization mass (wt) can also be obtained by monitoring the mass (wt) change of the liquid storage device 8 per unit time.

[0061] The deep devolatilization device includes a crushing and separation device 9 and a gas-liquid stirring kettle 10 connected to the crushing and separation device 9, wherein the crushing and separation device 9 is used to crush the high-viscosity polymer discharged from the material discharge port 12 of the devolatilizer 1, and the gas-liquid stirring kettle 10 is used to deeply devolatilize the crushed high-molecular polymer particles, and the deep devolatilization heating system is used to heat the gas-liquid stirring kettle 10. A high-viscosity glue liquid delivery pump 15 is also provided between the crushing and separation device 9 and the material discharge port 12 of the devolatilizer 1, so that the high-viscosity glue liquid can be smoothly delivered to the crushing and separation device 9.

[0062] The deep devolatilization device also includes a pump 14 for conveying hot liquid medium to the crushing and separation device 9. The hot liquid medium of this scheme is set as water, and the hot liquid medium comes from outside this scheme. The colloid water crushed by the crushing and separation device 9 is conveyed to the gas-liquid stirring kettle 10 for deep devolatilization, and the colloid water after deep devolatilization is pumped into the next process.

[0063] Example 1

[0064] In this embodiment, the high molecular weight polymer elastomer SIS\SBS is devolatilized, and the medium for removal is cyclohexane. The method and device used are as follows: Figure 1 and Figure 2 As shown. The heat medium used for devolatilization is 0.8∽1.0MPa steam and 90℃∽98℃ hot water. Among them, the heat capacity of cyclohexane is 1.68kJ / (kg·℃), the vaporization enthalpy of cyclohexane is 4.27×102kJ / kg, and the azeotropic point with water is 68.95℃. The hot water is used for deep devolatilization, and its flow rate is 12m 3 / h.

[0065] The specific devolatilization process is:

[0066] 1) Calculate the devolatilization mass of each section

[0067] The SBS glue liquid enters from the material inlet 11 of the devolatilizer 1, the feed rate is 300kg / h, the initial SBS glue liquid solid content (wt%) is 16%, the first stage devolatilization target value of the SBS glue liquid solid content (wt%) is set to 35%; the second stage deep devolatilization target value is set to the cyclohexane content in the SBS glue particles ≤ 1000ppm (wt%). The amount of pure SBS high molecular polymer is 48kg / h, and the amount of cyclohexane solvent is:

[0068] 300kg / h-48kg / h=252kg / h;

[0069] When the solid content of SBS glue is 35%, the amount of cyclohexane solvent contained is:

[0070] (48kg / h) / (35%)-48kg / h=89.143kg / h;

[0071] The amount of solvent removed is: 252kg / h-89.143kg / h=162.857kg / h;

[0072] Therefore, the first target devolatilization mass is 162.857 kg / h, that is, the mass (wt) of volatiles removed by the devolatilizer 1 per hour, of which cyclohexane accounts for 64.63%; the second devolatilization target is to remove cyclohexane in the SBS glue with a solid content of 35% in the deep devolatilization stage, that is, to remove 89 kg / h of cyclohexane, that is, the mass of volatiles that should be removed by the gas-liquid stirring reactor 10 per hour.

[0073] 2) Open the device for devolatilization

[0074] From the calculated data in step 1), it can be known that the SIS feed rate is 300kg / h, the initial SBS glue solid content (wt%) is 10%, and the temperature is 65°C. The SBS glue enters the body of the devolatilizer 1 from the material inlet 11, and then is heated by the shell and the internal components of the cavity of the three-section area of ​​the devolatilizer 1. The heating temperature of the shell of the devolatilizer 1 is 110∽150°C, and the heating temperature of the cavity of the devolatilizer 1 is 150∽178°C; the cyclohexane in the SBS glue is removed from the three devolatilization ports of the devolatilizer 1 and enters the recovery device; the mass of the cyclohexane removed is 214.19kg / h, and the removal rate accounts for 79.33%. At this time, the solid content of the SBS glue reaches 32%∽35% (wt%), and the steam consumption is 1.013t / t. The SBS glue liquid after devolatilization is discharged from the material outlet 12 of the devolatilizer 1 and enters the crushing and separation device 9, where it is mechanically crushed and separated under the condition of hot water at 90°C to 98°C. The SBS glue liquid after crushing and separation becomes glue particles and enters the gas-liquid stirring kettle 10 for deep devolatilization. The cyclohexane released enters the recovery device, and the glue particle water enters the subsequent process. At this time, the cyclohexane content in the glue particles is 850 to 1000 ppm (wt%) and the particle size is Length: 5∽9mm.

[0075] It can be seen from the above data that the device and method provided by the present invention are used to deeply devolatilize the high molecular polymer. Based on the setting of the three-stage devolatilization zone of the devolatilizer, the cyclohexane removal rate reaches 79.33%, which is much higher than the 64.63% removal rate of the devolatilizer in the calculation, providing a good precursor for the subsequent deep devolatilization. Furthermore, after deep devolatilization, the cyclohexane content in the obtained colloid particles is only 850∽1000ppm, the cyclohexane removal rate is ≥99.9%, and it has good continuous performance.

Claims

1. A high molecular polymer devolatilization device, characterized in that: The invention comprises a devolatilizer (1), a deep devolatilization device and a gas treatment device; a rotor shaft (2) is arranged on the central axis of the long axis of the devolatilizer, and a rotor shaft heating system is arranged inside the rotor shaft for controlling the temperature of the rotor shaft; a first devolatilization area (4), a second devolatilization area (5) and a third devolatilization area (6) are arranged in sequence inside the devolatilizer along the direction of entry of the rotor shaft, a jacket heating system is arranged between the first, second and third devolatilization areas and the devolatilizer shell, and each devolatilization area is provided with a volatilization channel (3) connected to the gas treatment device; the devolatilizer is provided with a high molecular polymer inlet (11) in the first devolatilization area, and a high molecular polymer outlet (12) connected to the deep devolatilization device in the third devolatilization area; and a nitrogen inlet (13) is also provided in the first devolatilization area for replacing the air atmosphere in the devolatilizer.

2. A high molecular polymer devolatilization device according to claim 1, characterized in that: The gas processing device comprises a gas-liquid separation tank (71), a first condenser (72), a pre-pump buffer tank (73), a vacuum pump (74), a second condenser (75) and a liquid storage device (8) which are connected in sequence; the liquid phase component in the pre-pump buffer tank (73) directly enters the liquid storage device through a pipeline, and the gas phase component enters the second condenser through the vacuum pump; the liquid storage device is also provided with an exhaust port directly connected to the first condenser.

3. A high molecular polymer devolatilization device according to claim 1, characterized in that: The deep devolatilization device comprises a colloid delivery pump (15), a crushing and separation device (9), a gas-liquid stirring kettle (10) and a delivery pump (14) which are connected in sequence; the material discharged from the high molecular polymer outlet of the devolatilizer enters the crushing and separation device for crushing through the colloid delivery pump; the gas-liquid stirring kettle is used to deeply devolatilize the crushed high molecular polymer particles to discharge volatiles and high molecular polymer; the delivery pump is also directly connected to the crushing and separation device for multiple devolatilization; the gas-liquid stirring kettle is also provided with an air inlet which is connected to the rotor shaft heating system and the jacket heating system.

4. A method for devolatilizing a high molecular polymer, characterized in that: The method is implemented by the device according to any one of claims 1 to 3, comprising the following steps: S1. The steam is passed into the devolatilizer jacket and the rotor shaft (2) to preheat the devolatilizer (1); S2. The polymer is fed from the polymer inlet (11) into the first devolatilization zone of the devolatilizer, and then the second devolatilization zone and the third devolatilization zone are devolatilized; S3 obtains the initial viscosity value of the polymer entering the devolatilizer, the viscosity value of the first devolatilization product, the viscosity value of the second devolatilization product and the devolatilization mass (wt). When the initial viscosity value is greater than 0 and the viscosity value of the first devolatilization product is equal to 0, start step S4. When the viscosity value of the first devolatilization product is greater than 0, start step S5. S4. According to the initial viscosity value, the first devolatilization product viscosity value and the second devolatilization product viscosity value and the devolatilization mass (wt), the rotor shaft (2) speed and the first devolatilization zone (4), the second devolatilization zone (5) and the third devolatilization zone (6) The devolatilization temperature; S5. Obtain the mass of polymer transported per unit time, taking the time from entering the devolatilizer (1) to exiting the devolatilizer (1) as the unit devolatilization time, obtain the initial viscosity value, the viscosity value of the first devolatilization product and the viscosity value of the second devolatilization product and the devolatilization mass (wt) within the unit devolatilization time, and adjust the devolatilization temperatures of the first devolatilization zone (4), the second devolatilization zone (5) and the third devolatilization zone (6) within the next unit devolatilization time; S6. The high molecular polymer after devolatilization in the devolatilizer (1) is transported to a crushing and separation device (9) for crushing and separation; S7. The polymer particles are deeply devolatilized to obtain the initial viscosity value of the deep devolatilization and the deep devolatilization mass per unit time (wt), and the devolatilization temperature and speed of the gas-liquid stirring reactor are adjusted; S8. Outputting the polymer particles after deep devolatilization; The devolatilization mass is the mass (wt) of volatiles removed from the polymer, and the deep devolatilization mass (wt) per unit time is the mass (wt) of volatiles removed from the polymer through the gas-liquid stirring kettle per unit time; The first devolatilization product is a polymer obtained by devolatilization treatment in the first devolatilization zone; The second devolatilization product is a polymer obtained by devolatilization treatment in the second devolatilization zone.

5. A high molecular polymer devolatilization method according to claim 4, characterized in that: The temperatures of the first, second and third devolatilization zones in S4 are obtained by: S4-1. The first devolatilization zone temperature: The first devolatilization zone temperature and the rotor shaft speed are set according to the initial viscosity value; S4-2. The second and third devolatilization zone temperatures: obtain the viscosity difference between the previous devolatilization zone product and the first two devolatilization zone polymers, and set the current devolatilization zone temperature; The temperature ranges of the first, second and third devolatilization zones are from one to five, namely: the first temperature is 80-100°C, the second temperature is 100-120°C; the third temperature is 120-140°C; the fourth temperature is 140-160°C; the fifth temperature is 160-190°C; The rotor shaft speed is high speed or low speed, the high speed is Low speed 6. A high molecular polymer devolatilization method according to claim 4, characterized in that: The temperature of the first devolatilization zone is: when the initial viscosity value is less than or equal to the first viscosity threshold, the devolatilization temperature of the first devolatilization zone (4) is set to a first temperature and the rotor shaft speed is a high speed; otherwise, the devolatilization temperature of the first devolatilization zone (4) is set to a second temperature and the rotor shaft speed is a low speed.

7. A high molecular polymer devolatilization method according to claim 4, characterized in that: The temperature of the second devolatilization zone is: when the difference between the viscosity value of the first devolatilization product and the initial viscosity value is ≤ the first viscosity difference, if the first devolatilization mass (wt) ≤ the first mass (wt) threshold, the devolatilization temperature of the second devolatilization zone (5) is set to the fourth temperature; if the first mass threshold < the first devolatilization mass (wt) ≤ the second mass threshold, the devolatilization temperature of the second devolatilization zone (5) is set to the third temperature; if the first devolatilization mass (wt) > the second mass threshold, the devolatilization temperature of the second devolatilization zone (5) is set to the second temperature; When the first viscosity difference is less than the difference between the first devolatilization product viscosity value and the initial viscosity value and less than or equal to the second viscosity difference, if the first devolatilization mass (wt) is less than or equal to the first mass threshold, the devolatilization temperature of the second devolatilization zone (5) is set to the fifth temperature level; if the first mass threshold is less than the first devolatilization mass (wt) is less than or equal to the second mass threshold, the devolatilization temperature of the second devolatilization zone (5) is set to the fourth temperature level; if the first devolatilization mass (wt) is greater than the second mass threshold, the devolatilization temperature of the second devolatilization zone (5) is set to the third temperature level; When the difference between the viscosity value of the first devolatilization product and the initial viscosity value is greater than the second viscosity difference, if the first devolatilization mass (wt) is less than or equal to the first mass threshold, the devolatilization temperature of the second devolatilization zone (5) is set to the sixth temperature level; if the first mass threshold is less than or equal to the first devolatilization mass (wt) less than or equal to the second mass threshold, the devolatilization temperature of the second devolatilization zone (5) is set to the fifth temperature level; if the first devolatilization mass (wt) is greater than the second mass threshold, the devolatilization temperature of the second devolatilization zone (5) is set to the fourth temperature level; The first viscosity difference refers to the difference between the viscosity value of the product in the second devolatilization zone and the viscosity value of the product in the first devolatilization zone, and the second viscosity difference refers to the difference between the viscosity value of the product in the third devolatilization zone and the viscosity value of the product in the first devolatilization zone; the first mass wt% threshold refers to the difference between the mass wt% of the product in the second devolatilization zone and the mass wt% of the product in the first devolatilization zone, and the second mass wt% threshold refers to the difference between the mass wt% of the product in the third devolatilization zone and the mass wt% of the product in the second devolatilization zone.

8. A high molecular polymer devolatilization method according to claim 4, characterized in that: The temperature of the third devolatilization zone is: when the difference between the viscosity value of the second devolatilization product and the viscosity value of the first devolatilization product is ≤ the first viscosity difference, the devolatilization temperature of the third devolatilization zone is set by the difference between the viscosity value of the second devolatilization product and the initial viscosity value and the second devolatilization mass; When the difference between the viscosity value of the second devolatilization product and the viscosity value of the first devolatilization product is greater than the first viscosity difference, if the second devolatilization mass (wt) is ≥ the third mass threshold, the devolatilization temperature of the third devolatilization zone (6) is set to a first temperature; if the second devolatilization mass (wt) is less than the third mass threshold, the devolatilization temperature of the third devolatilization zone is set by the difference between the viscosity value of the second devolatilization product and the initial viscosity value and the second devolatilization mass.

9. A method for devolatilization of a high molecular polymer according to claim 8, characterized in that: The process of setting the devolatilization temperature of the third devolatilization zone by the difference between the viscosity value of the second devolatilization product and the initial viscosity value and the second devolatilization mass (wt) is as follows: When the difference between the viscosity value of the second devolatilization product and the initial viscosity value is ≥ the third viscosity difference, if the second devolatilization mass (wt) is ≥ the third mass threshold, the devolatilization temperature of the third devolatilization zone is set to the second temperature; if the second devolatilization mass (wt) is < the third mass threshold, the third devolatilization zone is calculated according to the devolatilization temperature formula; When the second viscosity difference is ≤ the difference between the viscosity value of the second devolatilization product and the initial viscosity value < the third viscosity difference, if the second devolatilization mass (wt) is ≥ the third mass threshold, the devolatilization temperature of the third devolatilization zone (6) is set to the first temperature; if the second devolatilization mass (wt) is < the third mass threshold, it is calculated according to the devolatilization temperature formula; when the difference between the viscosity value of the second devolatilization product and the initial viscosity value is < the second viscosity difference, if the second devolatilization mass (wt) is ≥ the third mass threshold, the devolatilization temperature of the third devolatilization zone (6) is set to the first temperature; if the second devolatilization mass (wt) is < the third mass threshold, it is calculated according to the devolatilization temperature formula; The devolatilization temperature formula is: Wherein, T3 is the devolatilization temperature of the third devolatilization zone, T2 is the devolatilization temperature of the second devolatilization zone; M is the total mass of the polymer to be devolatilized; M1 is the first devolatilization mass; and M2 is the second devolatilization mass.

10. A high molecular polymer devolatilization method according to claim 1, characterized in that: The temperatures of the first, second and third devolatilization zones in S5 are obtained by: S5-1. The formula for calculating the unit devolatilization time of the polymer transported per unit time from entering the devolatilizer (1) to discharging the devolatilizer (1) is: Where t is the unit devolatilization time, V 聚 is the volume of polymer transported per unit time, S 桶 is the cross-sectional area of ​​the devolatilizer, v 轴 is the propulsion speed of the rotor shaft, d 桶 is the length of the devolatilizer, and k is the volume coefficient of the devolatilizer. S5-2 obtain the initial viscosity value, the first devolatilization product viscosity value, the second devolatilization product viscosity value and the devolatilization mass (wt) per unit devolatilization time n times, calculate the average initial viscosity, the average first devolatilization product viscosity, the average second devolatilization product viscosity and the average devolatilization mass (wt); S5-3. Obtain the difference between the average viscosity of the first devolatilization product and the average initial viscosity within the current unit devolatilization time, the difference between the average viscosity of the second devolatilization product and the average viscosity of the first devolatilization product, and the average devolatilization mass (wt); when the average devolatilization mass (wt) = the first target devolatilization mass (wt), maintain the temperature set for each area in S4; when the average devolatilization mass (wt) < the first target devolatilization mass (wt), calculate the temperature of each devolatilization area by the unit time devolatilization temperature formula; The formula for the devolatilization temperature per unit time is: Among them, M 目 is the first target devolatilization mass (wt), is the average devolatilization mass (wt), T 前 is the devolatilization temperature of the devolatilization area within the current unit devolatilization time, T 下 is the devolatilization temperature of the devolatilization zone within the next unit devolatilization time. 下 When the calculated value is greater than the maximum devolatilization temperature that the polymer can withstand, then T 下 Take the maximum devolatilization temperature.

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