Interactions of Exocellular Proteins, Polysaccharide and Cations During Bioflocculation in Suspended Growth Bioreactors

9907333 Higgins该项目的目的是发展一个基本的理解阳离子和胞外生物聚合物之间的相互作用，在悬浮生长生物反应器中的废水处理过程中产生的微生物。 该项目将解决影响细菌聚集成絮体、其沉降特性和脱水性的因素。 先前的研究表明，凝集素，一类由许多细菌产生的蛋白质，可以为生物絮体的形成提供桥接机会。 这项工作的最初重点将是确定凝集素在结合多糖和阳离子中的作用，作为获得比现在更好的理解的一个步骤。 实验室生物反应器将用于研究操作因素的影响，包括阳离子来源及其浓度。 待研究的来源包括钙、镁、钠和铁，操作条件包括平均细胞停留时间。 将分析絮凝物样品的稳定性、沉降和脱水性能。 该项目的结果可能会改善基于悬浮生长生物絮凝反应器的废水处理工艺的工程设计和操作。 因此，这项研究有可能显著提高生物处理工艺的效率，从而降低资本和运营费用，和/或提高基于使用悬浮的生物活性絮凝物的工艺的效率。

9907333 Higgins The objective of this project is to develop a fundamental understanding of the interactions between cations and exocellular biopolymers produced by microorganisms during processing of wastewaters in suspended growth bioreactors. The project will address factors that affect aggregation of bacteria into flocs, their settling characteristics and dewaterability. Previous work has shown that lecitins, a class of proteins produced by many bacteria, can provide bridging opportunities for the formation of bioflocs. The initial focus of this work will be to determine the role that lecitins play in binding polysaccharides and cations as a step toward obtaining a better understanding than now exists of biofloc formation. Laboratory bioreactors will be used to study the effect of operational factors including the source of cations and their concentrations. Sources to be investigated will include calcium, magnesium, sodium and iron and operational conditions will include mean cell residence time. Floc samples will be analyzed for their stability, settling and dewateringl properties. Results of this project are likely to improve the engineering design and operation of wastewater treatment processes that are based on use of suspended growth biofloc reactors. This research therefore has the potential of significantly improving the efficiency of biological treatment processes with the resulting decrease in capital and operation expense and/or improvement in the efficiency of processes based on use of suspended biologically active flocs.***