Innovative Fluidization Technologies for Green Processes

简介：流化床干燥广泛应用于制药、化肥、食品、农业和石化行业的干燥过程。然而，这种能源密集型工艺需要设计和操作解决方案，以最大限度地减少其能源消耗和环境足迹。流化床已被用作将生物质转化为绿色能源的有效工具。颗粒混合和分离在流化床反应器的整体工艺效率中起着重要作用。该研究计划将开发创新解决方案，通过引入脉冲气流来提高干燥性能。此外，基于同步加速器的X射线成像将用于揭示流化床内的新信息，以进一步提高能量转换。目的：具体的短期目标是：1）研究脉冲流对流化床干燥器中药物颗粒的起泡和干燥行为的影响; 2）使用计算流体动力学（CFD）开发干燥过程的数学模型和数值模拟;以及3）通过新型同步加速器X射线成像技术研究流化床中涉及生物质材料的二元混合物的混合和分离。方法：将首先努力放在调查干燥和鼓泡行为的药物粉末在脉动辅助流化床干燥器（目标1）。干燥实验将在一个锥形流化床干燥器中进行，该干燥器配备了UofS提供的电容层析成像（ECT）系统。将测量干燥速率并与收集的起泡数据相关联。CFD是一种先进的建模和数值模拟工具，将用于模拟有/无脉冲流的干燥过程（目标2）。从实验中确定的干燥速率和起泡行为将用于验证数值模拟。同时，同步加速器为基础的X射线计算机断层扫描（CT）将调查混合和分离的二元混合物，涉及生物质颗粒在流化床（目标3）。所获得的全面知识将改善流化床气化炉的操作。影响：拟议的研究计划将产生全面的知识，强化流化床干燥过程中的制药应用与脉冲气流。根据工作成果，将提供优化的操作范围，以减少与该单元操作相关的能源使用和环境足迹。关于在各种操作条件下的混合和分离的详细信息将告知用于各种热过程的流化床反应器的有效操作，目的是从可再生生物质资源，特别是颗粒燃料生产清洁能源。我的长期目标是扩大研究计划，使肥料，食品，采矿和农业行业的其他干燥过程受益。

INTRODUCTION: Fluidized bed drying is widely used for drying processes in the pharmaceutical, fertilizer, food, agriculture, and petrochemical industries. However, this energy-intensive process requires design and operation solutions to minimize its energy consumption and environmental footprint. Fluidized beds have been used as effective vehicles to convert biomass into green energy. Particle mixing and segregation plays an important role in the overall process efficiency of fluidized bed reactors. This research program will develop innovation solutions to enhance the drying performance by introducing pulsed gas flow. In addition, synchrotron-based X-ray imaging will be used to reveal new information within fluidized beds to further improve energy conversion. OBJECTIVES: Specific short-term objectives are to: 1) Investigate the effect of pulsed flow on bubbling and drying behaviour of pharmaceutical particles in a fluidized bed dryer; 2) Develop mathematical models and numerical simulations of drying processes using computational fluid dynamics (CFD); and 3) Investigate mixing and segregation of binary mixtures involving biomass materials in fluidized beds via novel synchrotron-based X-ray imaging techniques. METHODS: Efforts will first be placed on investigating drying and bubbling behaviour of pharmaceutical powders in a pulsation-assisted fluidized bed dryer (Objective 1). Drying experiments will be conducted in a conical fluidized bed dryer equipped with an electrical capacitance tomography (ECT) system available at the UofS. Drying rate will be measured and correlated with bubbling data collected. CFD, an advanced modeling and numerical simulation tool, will be employed to simulate the drying process with/without pulsed flow (Objective 2). Both the drying rate and bubbling behaviour determined from the experiments will be used to validate numerical simulations. In parallel, synchrotron-based X-ray computed tomography (CT) will be employed to investigate mixing and segregation of binary mixtures involving biomass pellets in a fluidized bed (Objective 3). The comprehensive knowledge obtained will improve operation of a fluidized bed gasifier. IMPACT: The proposed research program will produce comprehensive knowledge of enhanced fluidized bed drying processes for pharmaceutical applications with pulsed gas flow. Based on the outcomes of the work, an optimized operation envelope will be provided to achieve a reduction in energy use and environmental footprint associated with this unit operation. Detailed information about mixing and segregation under various operating conditions will inform efficient operation of fluidized bed reactors for various thermal processes with an aim to produce clean energy from renewable biomass resources, particularly pellet fuels. My long-term objective is to expand the research program to benefit other drying processes in fertilizer, food, mining, and agricultural industries.