Flowsheet simulation of integrated precipitation processes examined for the case of a modular micro reaction setup

在液相中生产各种各样的颗粒材料。由于其模块化，使高灵活性和连续操作，微反应技术（MRT）正在发挥越来越重要的作用。叠加机制使降水具有高度动态性，对过程参数的微小变化也很敏感。本项目的目标是开发一个广泛的和普遍适用的模块，描述降水过程中的MRT设置的动态流程模拟环境Dyssol。除了模拟，工艺优化是当今工程的一个重要方面，因此也包括在本项目中。几种不同的无机材料系统在整个项目中用于模型开发，以确保设备和反应的灵活性。模型描述的子过程，如混合和复杂的形成，以及几个竞争性的固体形成过程是密切相关的。通常使用的粒度分布（PSD）作为分散相的描述通常不足以解释所有相关的整体性质。因此，该工具被扩展以允许并行地遵循两个分散性质（2D），例如核-壳颗粒的核尺寸和壳厚度或基于各向异性生长和定向附聚的形状各向异性。多个固体的形成是通过一个简化的，数值上有效的种群平衡模型，通过多个阶段的并行平衡来处理的。根据整个项目中应用的缓慢、反应控制和快速混合控制系统的分类，将描述MRT装置中奥斯特瓦尔德熟化的现有流程图模块与快速沉淀系统的工作相结合。根据主导过程的时间尺度，选择最合适的方法和相应的求解器，以保证高的数值稳定性和短的计算时间。最后，开发了一个用于MRT设置过程优化的模块。虽然标准流程模拟模型仅考虑所有工艺参数总和对分散性能的影响，但优化需要考虑每个工艺参数对各自辅助物的影响。与无梯度方法相比，应用基于梯度的方法具有更快的收敛速度，这允许在流程图模拟框架内进行优化。因此，在完成本研究计画后，连续MRT装置中的动态降水过程有可能在流程模拟中被建模和优化。

A wide range of particulate materials is produced in liquid phase. Due to its modularity which enables high flexibility and continuous operation, micro reaction technology (MRT) is playing an increasingly important role. Superimposing mechanisms make precipitation highly dynamic and sensitive against even slight variations in process parameters. The target of the present project is the development of an extensive and generally applicable module describing precipitation processes in MRT setups for the dynamic flow sheet simulation environment Dyssol. Besides simulation, process optimization is an important aspect in today's engineering and is therefore included in this project. Several different inorganic material systems are used throughout this project for model development to ensure flexibility with respect to apparatus and reaction. Models describing sub-processes such as mixing and complex formation as well as several competitive solid formation processes are closely linked. The commonly used particle size distribution (PSD) as description of the disperse phase is often insufficient to account for all relevant ensemble properties. Therefore, the tool is extended to allow for two disperse properties (2D) being followed in parallel, such as core size and shell thickness of core-shell particles or shape anisotropy based on anisotropic growth and oriented agglomeration. The formation of multiple solids is treated via parallel balancing over multiple phases by a reduced, numerically efficient population balance model. According to the categorization into slow, reaction controlled and fast mixing controlled systems that has been applied throughout the whole project, an existing flow sheet module describing Ostwald ripening in MRT setups is combined with the work on fast precipitation systems. Based on the time scale of the dominating processes, the most appropriate method and the corresponding solver is selected to guarantee high numerical stability and short computational time. Finally, a module designated for process optimization of MRT setups is developed. While models for standard flow sheet simulation only consider the impact of the total of all process parameters on the disperse properties, optimization requires the impact of each process parameter in terms of the respective adjunct. The possibility of applying a gradient-based method with its faster convergence compared to gradient-free methods allows the optimization within a flow sheet simulation framework. Hence, after finishing this research project, dynamic precipitation processes in continuous MRT setups are possible to be modeled and optimized in flow sheet simulations.