热熔融流化床包衣过程液固接触凝固结合机理及产品品质控制

热熔融流化床包衣是制备微胶囊的一种先进技术。食品行业中，把食品添加剂包衣微胶囊化，使其免受外界不良影响，或利用微胶囊的缓释作用以发挥食品添加剂的效能。但颗粒包衣过程目前仍然是一个“经验化”的单元操作，有关包衣机理方面的研究尚未完全明确，工业化操作缺乏安全可靠的理论指导。本研究以亲脂性和亲水性微胶囊的制备为研究对象，通过颗粒群平衡模型与计算流体力学方法进行数学模拟，并结合具体实验，研究热熔融流化床包衣过程中熔融液滴与流化固体颗粒的结合机理；构建能够准确描述该包衣过程的数学模型；得出基于雾化、流化过程及产品原材料特性的热熔融颗粒包衣临界区域分布及判断准则；实现热熔融流化床包衣操作平稳运行和产品质量可控。

Hot melt fluidized bed encapsulation is an advanced coating technology in food industry, food additives are often encapsulated to protect the undesirable influence from the environment or have controlled release. However, particle coating process is still an empirical unit operation and its mechanism is not yet to be established. The theoretical guidance is not available for industrial safe and robust operations. Therefore, aimed to produce hydrophilic and lipophilic encapsulated particles, the project will investigate the contact mechanism of melt liquid droplet and fluidized solid particles by experimentation and mathematical modeling with Population Balance Model (PBM) and Computational Fluid Dynamics (CFD). The mathematical model for encapsulation will be established to represent this process. In terms of spray, fluidization and physical properties of raw materials, the critical regimes and evaluation criterion will be obtained for hot melt fluidized bed encapsulation, to achieve the objectives of stable operation and product quality control.