Towards Energy Efficiency Through Low-DO Nitrification: Extending our Knowledge of Ammonia-Oxidizing Organisms

通过低DO硝化提高能源效率：扩展我们对废水处理中氨氧化生物的认识活性污泥法是一个常见的过程。活性污泥是最大的能源使用者，因为维持好氧(富氧)条件所需的氧气量很大。这项建议寻求识别和表征在低DO条件下执行氨氧化并从而降低该过程成本的新型生物。该假说认为，在低溶解氧活性污泥系统中，未被识别的氨氧化生物可能是硝化作用的原因。如果这项研究成功，将大大降低美国许多废水处理厂的能源成本。该项目还将允许PIs继续指导高中生、本科生和研究生，并将资助培训两名来自代表不足的科学和工程群体的博士生。从技术上，该项目分为三项任务：1)筛选从执行高效硝化的实验室规模的反应器中分离出来的纯培养物，2)专注于鉴定实验室规模的反应器中丰富的氨氧化微生物，以及3)进行动力学实验，以表征耦合和处理大型污水处理厂一级出水的中试反应器中的微生物群落。强化生物除磷和低溶解氧硝化的有效耦合将是一项变革性的发展，因为用于去除养分的曝气可占能源消耗的近一半。该项目将促进新技术的开发，有助于实现废水处理行业的总体目标，即实现能源中立，并将重点从废物处理转移到资源回收设施。

1435661NogueraTowards Energy Efficiency Through Low-DO Nitrification: Extending our Knowledge of Ammonia-Oxidizing Organisms In wastewater treatment activated sludge is a common process. Activated sludge is the single largest energy user because of the amount of oxygen that is needed to maintain aerobic (oxygen rich) conditions. This proposal seeks to identify and characterize the novel organisms that perform ammonia oxidation under low-DO conditions and thereby reducing the cost of the process. The hypothesis is that unrecognized ammonia-oxidizing organisms are likely responsible for nitrification in low-dissolved oxygen activated sludge systems. If this study is successful it will result in a significant reduction in energy costs for many wastewater treatment plants in the Nation. The project will also allow the PIs to continue mentoring high school, undergraduate, and graduate students, and will fund the training of two PhD students from underrepresented groups in science and engineering.Technically, the project is divided into three tasks which include; 1) screening a collection of pure cultures isolated from a lab-scale reactor performing efficient nitrification, 2) focused on the identification of the abundant ammonia-oxidizing organisms in lab-scale reactors, and 3) conduct kinetic experiments to characterize the microbial communities in pilot-scale reactors coupling and treating primary effluent from a full scale wastewater treatment plant. The effective coupling of enhanced biological phosphorus removal and low-dissolved oxygen nitrification will be a transformative development, since aeration for nutrient removal can account for nearly half of the energy use. This project will enable development of new technologies that contribute to the wastewater industry's overarching goals of achieving energy neutrality and shifting the focus from waste treatment to resource recovery facilities.