液相沉淀反应在管式微通道反应器中的流动行为研究

doi:10.11949/0438-1157.20220609

摘要/Abstract

摘要：

以碳酸钙水相合成为模型反应，借助对流动反应过程的放大观测，从沉淀悬浮液的流变特性分析了液相沉淀反应在毫米级管式微通道中的流动行为特征以及通道堵塞的过程机理。结果表明，碳酸钙-水悬浮体系的黏度在低剪切速率下随固含率的增加而飙升，而反应通道堵塞的本质可归因于在壁面和流动主体区形成了固含率较高的局部高黏区，使流动性严重恶化。提高反应的流速加快了壁面沉积层和沉淀颗粒团聚体的形成，反而加快了堵塞；其中团聚体的形成远快于沉积层的积累，使团聚体的“架桥”虽晚于沉积层出现，却成为管路堵塞的主要因素。基于破坏流动壁面和主体的局部高黏区，设计了两种新型的微通道反应器模型，有可能为解决反应通道堵塞这一难题提供新的思路。

关键词: 沉淀, 反应器, 流动, 堵塞机理, 黏度, 流变学, 悬浮系, 团聚

Abstract:

With the aqueous-phase synthesis of calcium carbonate (CaCO₃) as the model reaction and based on the magnifying observation of flow-reaction process, the flow behavior characteristics of liquid-phase precipitation reaction in the milli-scale tubular microchannel and the mechanism of channel clogging were analyzed from the rheological properties of the suspension. The results showed that the viscosity of CaCO₃-water suspension increased sharply with the increase of solid content at low shear rate and the nature of clogging could be attributed to the formation of local high viscosity area with high solid content on the wall and in the bulk flow, which made the fluidity seriously deteriorate. Increasing the flow rate of the reaction accelerated the formation of sedimentary layer and precipitation particle aggregates, thus the clogging was accelerated. The formation of aggregates was much faster than the accumulation of sedimentary layer, making“bridging”of aggregates the main factor of channel clogging. Based on the local high-viscosity region that destroys the flow wall and main body, two new microchannel reactor models are designed, which may provide new ideas for solving the problem of clogging of the reaction channel.

Key words: precipitation, reactors, flow, clogging mechanism, viscosity, rheology, suspensions, agglomeration

中图分类号:

TQ 021.1

姚翰林, 辛忠. 液相沉淀反应在管式微通道反应器中的流动行为研究[J]. 化工学报, 2022, 73(8): 3518-3528.

Hanlin YAO, Zhong XIN. Research on flow behavior of liquid-phase precipitation reaction in the tubular microchannel reactor[J]. CIESC Journal, 2022, 73(8): 3518-3528.

图/表 17

图1 CaCO3水相连续流合成的可视化观测流程示意图

Fig. 1 Schematic diagram of visual observation process for CaCO3 aqueous-phase continuous flow synthesis

图2 旋转流变仪及同轴圆筒夹具

Fig. 2 Rotational rheometer and coaxial cylinder module

图3 悬浮液黏度随固含率的变化及可能的“沉积-堵塞”机理

Fig.3 Change of suspension viscosity over solid content and a possible “sedimentation-clogging” mechanism

图4 不同流速下CaCO3的水相流动合成过程随反应时间的变化

Fig.4 Changes of CaCO3 aqueous-phase flow-synthesis process over reaction time at different flow rates

图5 管内径为1 mm时CaCO3的水相流动合成过程随反应时间的变化

Fig.5 Change of CaCO3 aqueous-phase flow-synthesis process over reaction time when the tube diameter was 1 mm

图6 加入表面活性剂时CaCO3的水相流动合成过程随反应时间的变化

Fig.6 Change of CaCO3 aqueous-phase flow-synthesis process over reaction time when adding surfactants

图7 不同流速下CaCO3沉淀的粒径分布

Fig.7 Particle size distribution of CaCO3 precipitation at different flow rates

图8 不同固含率下CaCO3-水悬浮液的黏度随剪切速率的变化

Fig.8 Changes of CaCO3-water suspension viscosity over shear rate at different solid contents

图9 固含率对悬浮液样品状态的影响

Fig.9 Effect of solid content on the suspension sample state

图10 粒径不同时CaCO3-水悬浮液的黏度随剪切速率的变化

Fig.10 Changes of CaCO3-water suspension viscosity over shear rate at different particle sizes

图11 沉淀颗粒的惯性运动对空隙中液相的挤压作用以及局部高黏区的形成

Fig.11 Extrusion of liquid phase in interspace by inertial motion of precipitation particles and formation of local high viscosity area

图12 沉积和架桥作用对管路压降的影响

Fig.12 Effects of sedimentation and bridging on the tube pressure drop

图13 壁面附近存在液层时沉淀颗粒团聚体的流动（管内径：4 mm；流量：50.000 ml/min）

Fig.13 Flow of precipitation particle aggregates when liquid layers exist near the wall surface (tube inner diameter: 4 mm; flow: 50.000 ml/min)

图14 含外环液层的微通道反应器（平面图）

Fig.14 Microchannel reactor with outer-ring liquid layer (plan)

图15 管式反应器的图解积分

Fig.15 Graphical integration of tube reactors

图16 套管式微通道反应器（平面图）

Fig.16 Tube-in-tube microchannel reactor (plan)

表1 两种新型静态混合式微通道反应器模型的潜在优劣势分析

Table 1 Analysis of potential superiorities and flaws of two novel static mixing microchannel reactor models

1. 对反应沉淀和流动壁面的阻隔作用更加明显

2. 可保持反应物浓度和反应速率不被降低

1. 可保持反应器本身的传热性能

2. 不存在液液两相的分离问题

1. 射流速度高，可有效破坏沉积层和团聚体

2. 混合效果好

劣势

1. 增加了对反应物料的传热阻力

2. 增加了反应容积（管长）

3. 增加了分离难度和原料成本

1. 降低了反应物浓度和反应速率，增加了反应容积（管长）

2. 均匀混合后反应沉淀仍可能在壁面沉积

1. 内管压力大

2. 微孔加工精度要求高

3. 反应物的物质的量比可能失准，需要通过实验验证

参考文献 37

4	Coley C W, Thomas D A, Lummiss J A M, et al. A robotic platform for flow synthesis of organic compounds informed by AI planning[J]. Science, 2019, 365(6453): eaax1566.
5	Lin H K, Dai C H, Jamison T F, et al. A rapid total synthesis of ciprofloxacin hydrochloride in continuous flow[J]. Angewandte Chemie International Edition, 2017, 56(30): 8870-8873.
6	Luo L M, Yang M, Chen G W. Continuous synthesis of reduced graphene oxide-supported bimetallic NPs in liquid-liquid segmented flow[J]. Industrial & Engineering Chemistry Research, 2020, 59(17): 8456-8468.
7	Onisuru O R, Alimi O A, Potgieter K, et al. Continuous-flow catalytic degradation of hexacyanoferrate ion through electron transfer induction in a 3D-printed flow reactor[J]. Journal of Materials Engineering and Performance, 2021, 30(7): 4891-4901.
8	Wang K, Luo G S. Microflow extraction: a review of recent development[J]. Chemical Engineering Science, 2017, 169(21): 18-33.
9	Yang L, Ładosz A, Jensen K F. Analysis and simulation of multiphase hydrodynamics in capillary microseparators[J]. Lab on a Chip, 2019, 19(4): 706-715.
10	Zhu K, Yao C Q, Liu Y Y, et al. Using expansion units to improve CO₂ absorption for natural gas purification — a study on the hydrodynamics and mass transfer[J]. Chinese Journal of Chemical Engineering, 2021, 29(1): 35-46.
11	Zhang L, Bo X F, Yao H L, et al. Zinc-catalyzed alkylation of aromatic amines in continuous flow[J]. Organic Process Research & Development, 2020, 24(10): 2078-2084.
12	Zhao F, Cambié D, Janse J, et al. Scale-up of a luminescent solar concentrator-based photomicroreactor via numbering-up[J]. ACS Sustainable Chemistry & Engineering, 2018, 6(1): 422-429.
13	Dong Z Y, Delacour C, Mc Carogher K, et al. Continuous ultrasonic reactors: design, mechanism and application[J]. Materials (Basel, Switzerland), 2020, 13(2): 344-368.
14	Dong Z Y, Fernandez R D, Kuhn S. Acoustophoretic focusing effects on particle synthesis and clogging in microreactors[J]. Lab on a Chip, 2019, 19(2): 316-327.
15	Hartman R L. Managing solids in microreactors for the upstream continuous processing of fine chemicals[J]. Organic Process Research & Development, 2012, 16(5): 870-887.
16	Mao M M, Zhang L, Yao H L, et al. Development and scale-up of the rapid synthesis of triphenyl phosphites in continuous flow[J]. ACS Omega, 2020, 5(16): 9503-9509.
17	Yao H L, Wan L, Zhao X Y, et al. Effective phosphorylation of 2,2'-methylene-bis(4,6-di-tert-butyl) phenol in continuous flow reactors[J]. Organic Process Research & Development, 2021, 25(9): 2060-2070.
18	Tamaki T, Nagaki A. Flash production of organophosphorus compounds in flow[J]. Tetrahedron Letters, 2021, 81: 153364.
19	Dong X R, Wang K, Luo G S. Microreaction continuous synthesis of gold nanoparticles[J]. Chinese Journal of Chemical Engineering, 2021, 72(7): 3823-3831.
20	Nagasawa H, Mae K. Development of a new microreactor based on annular microsegments for fine particle production[J]. Industrial & Engineering Chemistry Research, 2006, 45(7): 2179-2186.
21	Nagasawa H, Tsujiuchi T, Maki T, et al. Controlling fine particle formation processes using a concentric microreactor[J]. AIChE Journal, 2007, 53(1): 196-206.
22	Cruz P C, Silva C R, Rocha F A, et al. Mixing performance of planar oscillatory flow reactors with liquid solutions and solid suspensions[J]. Industrial & Engineering Chemistry Research, 2021, 60(6): 2663-2676.
23	Ley S V, Fitzpatrick D E, Myers R M, et al. Machine-assisted organic synthesis[J]. Angewandte Chemie International Edition, 2015, 54(35): 10122-10136.
24	Sleveland D, Bjørsvik H R. Synthesis of phenylboronic acids in continuous flow by means of a multijet oscillating disc reactor system operating at cryogenic temperatures[J]. Organic Process Research & Development, 2012, 16(5): 1121-1130.
25	Mo Y M, Lin H K, Jensen K F. High-performance miniature CSTR for biphasic C—C bond-forming reactions[J]. Chemical Engineering Journal, 2018, 335: 936-944.
26	Kern D Q, Seaton R A. A theoretical analysis of thermal surface fouling[J]. British Chemical Engineering, 1959, 4(5): 258-262.
27	Trofa M, D'Avino G, Sicignano L, et al. CFD-DEM simulations of particulate fouling in microchannels[J]. Chemical Engineering Journal, 2019, 358: 91-100.
28	Hartman R L, Naber J R, Zaborenko N, et al. Overcoming the challenges of solid bridging and constriction during Pd-catalyzed C—N bond formation in microreactors[J]. Organic Process Research & Development, 2010, 14(6): 1347-1357.
29	Sicignano L, Tomaiuolo G, Perazzo A, et al. The effect of shear flow on microreactor clogging[J]. Chemical Engineering Journal, 2018, 341: 639-647.
30	Hsu C P, Ramakrishna S N, Zanini M, et al. Roughness-dependent tribology effects on discontinuous shear thickening[J]. Proceedings of the National Academy of Sciences of the United States of America, 2018, 115(20): 5117-5122.
31	杨红娟, 韦方强, 胡凯衡, 等. 不同上限粒径泥石流浆体的流变参数变化规律[J]. 水利学报, 2016, 47(7): 884-890.
	Yang H J, Wei F Q, Hu K H, et al. Rheological parameters of debris flow slurries with different maximum grain sizes[J]. Journal of Hydraulic Engineering, 2016, 47(7): 884-890.
1	Adamo A, Beingessner R L, Behnam M, et al. On-demand continuous-flow production of pharmaceuticals in a compact, reconfigurable system[J]. Science, 2016, 352(6281): 61-67.
2	Bogdan A, Poe S, Kubis D, et al. The continuous-flow synthesis of ibuprofen[J]. Angewandte Chemie International Edition, 2009, 48(45): 8547-8550.
3	Cambié D, Bottecchia C, Straathof N J W, et al. Applications of continuous-flow photochemistry in organic synthesis, material science, and water treatment[J]. Chemical Reviews, 2016, 116(17): 10276-10341.
32	茅梦梅, 万力, 辛忠. 抗氧剂168的连续流高效制备[J]. 精细化工, 2019, 36(10): 2151-2154.
	Mao M M, Wan L, Xin Z. Highly efficient synthesis of antioxidant 168 in continuous flow[J]. Fine Chemicals, 2019, 36(10): 2151-2154.
33	Boylu F, Dinçer H, Ateşok G. Effect of coal particle size distribution, volume fraction and rank on the rheology of coal-water slurries[J]. Fuel Processing Technology, 2004, 85(4): 241-250.
34	Singh H, Kumar S, Mohapatra S K, et al. Slurryability and flowability of coal water slurry: effect of particle size distribution[J]. Journal of Cleaner Production, 2021, 323: 129183.
35	Guillot P, Colin A. Determination of the flow curve of complex fluids using the Rabinowitsch-Mooney equation in sensorless microrheometer[J]. Microfluidics and Nanofluidics, 2014, 17(3): 605-611.
36	Levenspiel O. Chemical Reaction Engineering[M]. New York: Wiley-VCH, 1999.
37	Foust A S. Principles of Unit Operations[M]. New York: John Willey and Sons Inc., 1980.

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