CAREER: Detachment from Biofilms Under Dynamic Operating Conditions - Integrating Fundamental Research and Practical Biofilm Modeling Education

0134104 Morgenroth该提案的总体目标是确定剪切应力的动态变化对生物膜脱离的影响。 生物膜分离的机制知之甚少，生物膜反应器的设计和操作程序主要是经验性的。 在生物膜反应器中，分离过程是平衡细菌生长和防止堵塞所必需的。 此外，整体速率和时间依赖性变化的脱离显着影响细菌的选择内的生物膜社区。 本提案的具体目标是确定在恒定或动态波动剪切条件下分离速率、分离颗粒特性和反应器总体性能之间的关系。 基于实验结果，将开发生物膜动态数学模型。 该模型将用于实验设计，研究结果的解释，并教学生和从业者的基本原则，生物膜在生物处理过程中的应用。将开发在线监测脱离情况的创新工具。 激光背散射和在线视频显微镜将被调整，以提供有关分离颗粒的尺寸和形状特征的连续信息。 将开发用于测量生物膜反应器内细菌呼吸速率的在线技术，并将其用于将生物膜反应器的整体性能与生物膜动力学相关联。 分离的颗粒还将表征强度、表面疏水性、表面电荷和硝化细菌的丰度。 将开发实验室规模的生物膜系统，使生物膜在规定的流体动力学条件下（环形反应器）或在全规模反应器（填充床反应器，气升式反应器）中使用的条件下生长。 建立生物膜数学模型，用于科研和教学。模型的输入将包括废水成分、生物膜厚度分布和分离的颗粒尺寸分布。 该数学模型将在实验室和全尺寸生物膜反应器中进行测试。

0134104MorgenrothThe overall objective of this proposal is to determine the influence of dynamic variations of shear stress on biofilm detachment. Mechanisms of biofilm detachment are poorly understood and procedures for the design and operation of biofilm reactors are mainly empirical. In biofilm reactors, the process of detachment is necessary to balance bacterial growth and to prevent clogging. In addition, the overall rate and time dependent variation of detachment significantly influence bacterial selection within the biofilmcommunity. Specific objectives of this proposal are to determine the relationship between detachment rate, detached particle characteristics, and overall reactor performance under constant or dynamically fluctuating shear conditions. Based on experimental results, a dynamic mathematical biofilm model will be developed. The model will be used for experimental design, interpretation of research results and toteach students and practitioners the underlying principles governing the application of biofilms in biological treatment processes. Innovative tools for on-line monitoring of detachment will be developed. Laser backscattering and in-line video microscopy will be adapted to provide continuous information on the size and shape characteristics of detached particles. On-line techniques for measuring bacterial respiration rates within the biofilm reactor will be developed and used to correlate overall biofilm reactor performance with detachmentdynamics. Detached particles will also be characterized for strength, surface hydrophobicity, surface charge, and abundance of nitrifying bacteria. Laboratory scale biofilm systems will be developed that allow biofilms to grow under defined hydrodynamic conditions (annular reactor) or under conditions used in full-scale reactors (packed bed reactor, airlift reactor). A mathematical biofilm model will be developedthat will be applied both in research and in teaching. Inputs to the model will consist of wastewater composition, biofilm thickness distribution, and detached particle size distribution. The mathematical model will be tested in the laboratory and in full-scale biofilm reactors.