流化床聚合反应器中液体耦合作用机制及其影响下的介尺度颗粒聚团与稳定性研究

持液气固流化床广泛应用于烯烃聚合、催化裂化、干燥及造粒等化工过程，但其中液体架桥和液体蒸发的耦合作用机制尚未明确。项目以流化床聚合反应器为研究背景，在特殊设计的热态实验装置中，综合利用声发射、压力脉动、摄像等多种在线检测手段，结合离线取样分析和信息融合分析，实现床层流化特性的多层次表征，依此建立液体架桥作用和液体蒸发作用的定量表征方法。系统考察液体耦合作用随液含量、流化气速等操作参数及液体、固体物性的变化规律，识别不同条件下的液体主导作用机制，获得液体耦合作用的有效调控手段。重点研究液体耦合作用机制下颗粒聚团及其稳定性的变化规律，通过时间尺度分析、力平衡分析、颗粒团聚和破碎控制机制分析等研究手段，关联介尺度的颗粒聚团和宏尺度的流化稳定性，建立颗粒聚团与稳定性分析模型，进而实现对颗粒聚团和流化稳定性的有效调控。研究成果可用于指导持液气固流化床反应器的放大设计和稳定运行。

Liquid-containing gas-solid fluidized beds have been applied widely in olefin polymerization, fluid catalytic cracking, drying and granulation processes and etc. The study on the mechanisms of liquid bridge and liquid evaporation coupling behaviors are quite rare from literature. Based on fluidized bed polymerization reactor, this project studies the mechanisms of liquid coupling behaviors in the self-designed hot-mode fluidized bed setup. Various online measuring techniques, including acoustic emission, pressure fluctuation and camera, together with off-line sampling analysis and data fusion analysis, are used to characterize the fluidization in the bed, and then to quantify the liquid bridge and liquid evaporation behaviors. The project attempts to systematically study the effects of the operating parameters (i.e. liquid content, gas velocity), liquid and solid physical properties (i.e. liquid viscosity, particle size and density) on the liquid coupling behaviors, to recognize the dominant liquid behavior mechanism under different conditions and then to obtain the effective control means on liquid behavior. Moreover, the project mainly studies the changing trends of particle agglomeration and its stability under the conditions of liquid coupling behavior mechanisms. Based on time scale analysis, force balance analysis and control mechanism analysis of particle agglomeration and breakup, the meso-scale particle agglomeration and macro-scale fluidization stability can be correlated to establish the model of meso-scale particle agglomeration and stability analysis. Furthermore, the effective control of particle agglomeration and fluidization stability can be obtained. The project can help to improve scale-up design and operation stability of liquid-containing gas-solid fluidized bed reactors.