POE溶液聚合反应器内混合与反应过程的CFD研究

doi:10.11949/0438-1157.20230635

摘要/Abstract

摘要：

聚烯烃弹性体(POE)具有优异的性能而应用广泛，其工业生产通常采用溶液聚合方法。POE反应介质流变行为复杂，受温度、剪切速率、聚合物浓度等诸多因素影响。同时，反应介质的流变行为是决定混合效果的重要因素，进而影响反应进程。由于反应、流变和流场的相互作用，POE溶液聚合反应器的设计和生产过程控制面临着挑战。基于实测的动力学和流变数据，针对POE溶液聚合反应器建立了一个耦合计算流体力学(CFD)模型，综合考虑了流动、混合效率、反应动力学和流变特性等方面的影响，探究了不同工艺条件(搅拌转速、停留时间、进料温度)对速度场、温度场、浓度场、流变特性等参数的影响规律，为优化实际工业过程提供参考。

关键词: 聚烯烃弹性体, 反应器, 计算流体力学, 流变模型, 聚合物, 动力学模型

Abstract:

Polyolefin elastomer (POE) has excellent properties and is widely used, and its industrial production usually adopts solution polymerization method. Industrial production of POE typically involves the solution polymerization process. The rheological behavior of the POE reaction medium is highly complex and influenced by several factors, including temperature, shear rate and polymer concentration. Moreover, the rheological behavior of the reaction medium significantly impacts the mixing efficiency, thereby affecting the reaction process. Due to the interaction of reaction, rheology, and flow field, the design and production process control of POE solution polymerization reactors are facing challenges. This study establishes a computational fluid dynamics (CFD) model that integrates flow dynamics, mixing efficiency, reaction kinetics and rheological properties for POE solution polymerization reactors, based on actual measured data for kinetics and rheology. The model enables a detailed investigation of the effects of various process conditions, such as stirring speed, residence time and feed temperature on the velocity field, temperature field, concentration field and rheological properties. The findings of this study provide valuable insights and guidance for optimizing actual industrial processes.

Key words: polyolefin elastomer, reactor, CFD, rheology, polymers, kinetic modeling

中图分类号:

TQ 325.1

麻雪怡, 刘克勤, 胡激江, 姚臻. POE溶液聚合反应器内混合与反应过程的CFD研究[J]. 化工学报, 2024, 75(1): 322-337.

Xueyi MA, Keqin LIU, Jijiang HU, Zhen YAO. CFD studies on the mixing and reaction in a solution polymerization reactor for POE production[J]. CIESC Journal, 2024, 75(1): 322-337.

图/表 24

图1 立式直叶桨式搅拌釜反应器结构

Fig.1 Structure of vertical straight blade paddle stirred tank reactor

图2 立式直叶桨式搅拌釜反应器多重参考系模型划分结果

Fig.2 Division results of multiple reference system model for vertical impeller stirred tank reactor

图3 网格划分结构

Fig.3 Grid division structure

表1 验证网格独立性模拟结果

Table1 Verify grid independence simulation results

网格数量/10⁴个	进出口温升/K	最小分子量	最大分子量	聚合物质量浓度/(kg/mol)	乙烯转化率/%	辛烯转化率/%	最大黏度/(Pa·s)
20	96.34	138600	138860	71.89	81.67	20.08	0.128
32	96.88	139400	139990	72.56	82.30	20.45	0.161
38	98.07	136200	137060	73.64	83.31	21.17	0.160
50	98.35	137400	138600	73.72	83.44	21.09	0.158

图4 速度相关分布云图

Fig.4 Cloud plot of velocity correlation distribution

图5 温度分布云图

Fig.5 Cloud plot of temperature distribution

图6 浓度场分布云图

Fig.6 Cloud plot of concentration field distribution

图7 黏度分布云图

Fig.7 Cloud plot of viscosity distribution

图8 不同搅拌转速下z轴速度分量流线云图

Fig.8 Cloud plot of velocity component in z-axis direction at different stirring speeds

图9 不同搅拌转速下温度分布云图

Fig.9 Cloud plot of temperature distribution under different stirring speeds

图10 不同搅拌转速下乙烯辛烯浓度比分布云图

Fig.10 Cloud plot of concentration ratio of ethylene to octene under different stirring speeds

图11 不同搅拌转速下乙烯辛烯反应速率比分布云图

Fig.11 Cloud plot of the reaction rate ratio of ethylene to octene under different stirring speeds

图12 不同搅拌转速下聚合物质量浓度分布云图

Fig.12 Cloud plot of polymer mass concentration distribution under different stirring speeds

表2 不同搅拌转速对POE聚合模拟结果的影响

Table 2 The effect of different stirring speeds on the simulation results of POE polymerization

搅拌转速/(r/min)	进出口温升/K	最小分子量	最大分子量	聚合物质量浓度/(kg/m³)	乙烯转化率/%	辛烯转化率/%	扭矩/(N·m)	搅拌功率/kW
100	98.69	138900	139350	73.6	83.45	20.84	23.01	0.24
200	98.06	136200	137060	73.6	83.31	21.17	122.66	2.57
300	96.58	138400	138780	72.1	81.82	20.20	195.28	6.13
1000	95.21	133891	133904	71.6	80.82	20.68	973.51	101.94

图13 不同停留时间下温度分布云图

Fig.13 Cloud plot of temperature distribution under different residence time

图14 不同停留时间下乙烯辛烯浓度比分布云图

Fig.14 Cloud plot of concentration ratio of ethylene to octene under different residence time

图15 不同停留时间下乙烯辛烯反应速度比分布云图

Fig.15 Cloud plot of reaction rate ratio of ethylene to octene under different residence time

图16 不同停留时间下聚合物质量浓度分布云图

Fig.16 Cloud plot of polymer mass concentration distribution under different residence time

表3 不同停留时间对POE聚合模拟结果的影响

Table 3 The effect of different residence time on the simulation results of POE polymerization

停留时间/min	进出口温升/K	最小分子量	最大分子量	聚合物质量浓度/(kg/m³)	乙烯转化率/%	辛烯转化率/%
13	101.6	121900	122400	77.2	85.63	25.05
10	98.06	136200	137060	73.6	83.31	21.17
8	93.25	154700	155500	68.7	79.37	17.03

图17 不同进料温度下温度分布云图

Fig.17 Cloud plot of temperature distribution at different feed temperature

图18 不同进料温度下乙烯辛烯浓度比分布云图

Fig.18 Cloud plot of concentration ratio of ethylene to octene at different feed temperature

图19 不同进料温度下乙烯辛烯反应速度比分布云图

Fig.19 Cloud plot of reaction rate ratio of ethylene to octene at different feed temperature

图20 不同进料温度下聚合物质量浓度分布云图

Fig.20 Cloud plot of polymer mass concentration distribution at different feed temperature

表4 不同进料温度对POE聚合模拟结果的影响

Table 4 The effect of different feed temperatures on the simulation results of POE polymerization

进料温度/℃	进出口温升/K	最小分子量	最大分子量	聚合物质量浓度/(kg/m³)	乙烯转化率/%	辛烯转化率/%
60	96.10	134900	135600	71.4	81.58	19.22
80	98.06	136200	137060	73.6	83.31	21.17
100	98.64	143000	143210	73.9	83.41	21.62

参考文献 30

1	李伯耿, 张明轩, 刘伟峰, 等. 聚烯烃类弹性体——现状与进展[J]. 化工进展, 2017, 36(9): 3135-3144.
	Li B G, Zhang M X, Liu W F, et al. State-of-the-art and research progress of polyolefin-based elastomer[J]. Chemical Industry and Engineering Progress, 2017, 36(9): 3135-3144.
2	朱玉俊. 介绍一种新型弹性体材料——聚烯烃弹性体(POE)[J]. 化工新型材料, 1998(10): 20-30.
	Zhu Y J. Introduce a new type of elastomer material—polyolefin elastomer(POE)[J] New Chemical Materials, 1998(10): 20-30.
3	李瑞敏, 郝巍, 刘杰, 等. 阻燃交联聚烯烃弹性体复合材料的制备及其性能研究[J]. 化工新型材料, 2020, 48(12): 250-254.
	Li R M, Hao W, Liu J, et al. Preparation and performance study of flame-retardant cross-linked polyolefin elastomer composite materials[J]. New Chemical Materials, 2020, 48(12): 250-254.
4	李良杰. 聚烯烃弹性体及其催化体系研究进展[J]. 弹性体, 2015, 25(5): 88-94.
	Li L J. Research progress in polyolefin elastomers and their catalytic systems[J]. Elastomer, 2015, 25(5): 88-94.
5	任静, 王彬, 傅宏俊, 等. 非茂钛配合物催化乙烯/α-烯烃共聚制备聚烯烃弹性体[J]. 高分子材料科学与工程, 2017, 33(4): 1-6.
	Ren J, Wang B, Fu H J, et al. Ethylene catalyzed by non titanocene complexes/α- preparation of polyolefin elastomers by olefin copolymerization[J]. Polymer Materials Science and Engineering, 2017, 33(4): 1-6.
6	张宇婷, 韩书亮, 吴宁, 等. 水杨醛亚胺合钛催化体系合成聚烯烃弹性体[J]. 塑料, 2018, 47(5): 117-121, 129.
	Zhang Y T, Han S L, Wu N, et al. Synthesis of polyolefin elastomers using salicylaldehyde imine titanium catalyst system[J]. Plastic, 2018, 47(5): 117-121, 129.
7	王金强, 田洲, 程瑞华, 等. CGC/i-Bu₃Al/Ph₃C⁺B(C₆F₅) 4 - 催化乙烯均聚及乙烯与1-辛烯共聚行为[J]. 合成树脂及塑料, 2018, 35(6): 15-21, 26.
	Wang J Q, Tian Z, Cheng R H, et al. CGC/i-Bu₃Al/Ph₃C⁺B(C₆F₅) 4 - catalyzed homopolymerization of ethylene and copolymerization of ethylene with 1-octene[J]. Synthetic Resins and Plastics, 2018, 35(6): 15-21, 26.
8	燕晓飞. PP/POE热塑性弹性体的制备和性能研究[D]. 青岛: 青岛科技大学, 2009.
	Yan X F. Preparation and performance study of PP/POE thermoplastic elastomer[D]. Qingdao: Qingdao University of Science and Technology, 2009.
9	孙建中, 潘勤敏, 顾培韵, 等. 共轭二烯烃溶液聚合连续搅拌塔式反应器的研究——流动模型[J]. 化学反应工程与工艺, 1993, 9(4): 437-443.
	Sun J Z, Pan Q M, Gu P Y, et al. Research on continuous stirred column reactor for conjugated diene solution polymerization—flow model[J]. Chemical Reaction Engineering and Process, 1993, 9(4): 437-443.
10	张芳丽, 何金学. 聚合反应器的应用研究进展[J]. 当代化工, 2022, 51(8): 1871-1875.
	Zhang F L, He J X. Research progress in the application of polymerization reactors[J]. Contemporary Chemical Industry, 2022, 51(8): 1871-1875.
11	许超众. 面向分子量分布的溶液聚合过程CFD建模[D]. 杭州: 浙江大学, 2018.
	Xu C Z. CFD modeling of solution polymerization process for molecular weight distribution[D]. Hangzhou: Zhejiang University, 2018.
12	张弛. 基于计算流体力学的聚合反应分子量分布的模拟与优化[D]. 杭州: 浙江大学, 2017.
	Zhang C. Simulation and optimization of molecular weight distribution in polymerization reactions based on computational fluid dynamics[D]. Hangzhou: Zhejiang University, 2017.
13	孔婧. 考虑传递现象的复杂聚合反应过程模拟与优化方法[D]. 杭州: 浙江大学, 2020.
	Kong J. A simulation and optimization method for complex polymerization reaction processes considering transfer phenomena[D]. Hangzhou: Zhejiang University, 2020.
14	Wells G J, Ray W H. Methodology for modeling detailed imperfect mixing effects in complex reactors[J]. AIChE Journal, 2005, 51(5): 1508-1520.
15	Zhang C, Shao Z J, Chen X, et al. Simulation and optimization of polymer molecular weight distribution with nonideal reactors[J]. Computers & Chemical Engineering, 2017, 106: 744-757.
16	López-Carpy B, Saldívar-Guerra E, Zapata-González I, et al. Mathematical modeling of the molecular weight distribution in low density polyethylene (Ⅰ): Steady-state operation of multizone autoclave reactors[J]. Macromolecular Reaction Engineering, 2018, 12(4): 1800013.
17	Meimaroglou D, Pladis P, Baltsas A, et al. Prediction of the molecular and polymer solution properties of LDPE in a high-pressure tubular reactor using a novel Monte Carlo approach[J]. Chemical Engineering Science, 2011, 66(8): 1685-1696.
18	Patel H, Ein-Mozaffari F, Dhib R. CFD analysis of mixing in thermal polymerization of styrene[J]. Computers & Chemical Engineering, 2010, 34(4): 421-429.
19	韩颖. 基于计算流体力学的烯烃聚合反应器模型化与模拟研究[D]. 杭州: 浙江大学, 2013.
	Han Y. Modeling and simulation of olefin polymerization reactors based on computational fluid dynamics[D]. Hangzhou: Zhejiang University, 2013.
20	Zhou W, Marshall E, Oshinowo L. Modeling LDPE tubular and autoclave reactors[J]. Industrial & Engineering Chemistry Research, 2001, 40(23): 5533-5542.
21	Fathi Roudsari S, Ein-Mozaffari F, Dhib R. Use of CFD in modeling MMA solution polymerization in a CSTR[J]. Chemical Engineering Journal, 2013, 219: 429-442.
22	刘伟峰. 乙烯/辛烯溶液共聚及其聚合物链结构的调控[D]. 杭州: 浙江大学, 2014.
	Liu W F. Ethylene/octene solution copolymerization and regulation of polymer chain structure[D]. Hangzhou: Zhejiang University, 2014.
23	赵根根. 聚烯烃弹性体亚浓溶液及熔体的流变特性研究[D]. 杭州: 浙江大学, 2018.
	Zhao G G. Study on the rheological properties of polyolefin elastomers in sub concentrated solutions and melts[D]. Hangzhou: Zhejiang University, 2018.
24	Brucato A, Ciofalo M, Grisafi F, et al. Numerical prediction of flow fields in baffled stirred vessels: a comparison of alternative modelling approaches[J]. Chemical Engineering Science, 1998, 53(21): 3653-3684.
25	Singh K K, Mahajani S M, Shenoy K T, et al. CFD modeling of pilot-scale pump-mixer: single-phase head and power characteristics[J]. Chemical Engineering Science, 2007, 62(5): 1308-1322.
26	Luo J Y, Gosman A D, Issa R I. Prediction of impeller-induced flows in mixing vessels using multiple frames of reference[J]. IChemE Symposium Series, 1994, 136(4): 549-556.
27	Pauli L, Both J W, Behr M. Stabilized finite element method for flows with multiple reference frames[J]. International Journal for Numerical Methods in Fluids, 2015, 78(11): 657-669.
28	李超. 气流床气化炉内颗粒流动模拟及分区模型研究[D]. 上海: 华东理工大学, 2013.
	Li C. Research on particle flow simulation and zoning model in an airflow bed gasifier[D]. Shanghai: East China University of Science and Technology, 2013.
29	Sommerfeld M, Decker S. State of the art and future trends in CFD simulation of stirred vessel hydrodynamics[J]. Chemical Engineering & Technology, 2004, 27(3): 215-224.
30	叶阳. 新型卧式双轴反应器的CFD模拟与传质研究[D]. 杭州: 浙江大学, 2019.
	Ye Y. CFD simulation and mass transfer study of a new horizontal biaxial reactor[D]. Hangzhou: Zhejiang University, 2019.

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