Inducing Aerobic Granulation in Continuous-Flow Reactors using Shear Variability

CBET-1336544 Francis de洛斯雷耶斯and Joel Ducoste北卡罗莱纳州立大学好氧造粒也许是好氧废水处理中最令人兴奋的发展之一，有希望在更小的反应器中处理更高流量的更高强度废水的能力，生物质的沉降和分离问题更少，并且具有处理各种有机基质的能力，以及同时去除氮和磷。 如果能在现有的污水处理设施中开发好氧颗粒污泥，其影响将是广泛的。 然而，尽管有这样的希望，连续流好氧颗粒污泥反应器的全面实施还没有发生。 连续流反应器理论上提供更稳定的环境，需要较少的自动化，并且可以由工程师使用较小的测试系统设计。 然而，在连续流反应器中从非颗粒状生物固体形成好氧颗粒还不清楚。 基于先前的研究，假设诱导好氧颗粒化的关键不是顺序分批模式，而是生物反应器提供可变剪切的能力。 本研究将测试这一假设，并调查反应器流体力学，微生物的反应，并最终在有氧条件下造粒之间的机械联系。 一个组合的方法，包括微反应器中的微生物形态变化的分析，在实验室规模的反应器中的种群和基因的分子微生物分析，以及使用计算流体动力学和拉格朗日传感器，将被用来显示如何剪切变异性是有氧造粒的必要条件。 最后，本研究将通过构建和操作连续流中试规模反应器来诱导好氧颗粒化来展示规模扩大。 这种结合的方法将展示好氧颗粒污泥技术如何用于改造现有的活性污泥厂，可能提供好氧处理技术的重大飞跃，并影响世界各地成千上万的污水处理厂。好氧颗粒生物质反应器的发展令污水处理行业兴奋，因为它代表了一种创新，高效，紧凑，和潜在的更可持续的废水处理方法。 好氧颗粒生物质反应器可以处理高浓度有机废水。该项目将潜在地使市政和工业废水处理厂受益，包括那些进行营养物去除的废水处理厂。 在现有的污水处理厂中开发好氧颗粒剂代表了技术的飞跃，为国家的污水基础设施带来了经济和效率效益。 这项创新研究的结果还将产生可用于课堂的信息，并通过发现的兴奋促进学习。

CBET-1336544Francis de los Reyes and Joel DucosteNorth Carolina State UniversityAerobic granulation is perhaps one of the most exciting developments in aerobic wastewater treatment, promising the ability to treat higher flows of higher strength wastewater in smaller reactors, with fewer problems with settling and separation of biomass, and with the ability to treat a variety of organic substrates, as well as simultaneously removal of nitrogen and phosphorus. If aerobic granular sludge can be developed in existing wastewater treatment facilities, the impacts would be widespread. Yet despite the promise, full-scale implementation of continuous flow aerobic granular sludge reactors has not happened. Continuous flow reactors theoretically provide more stable environments, need less automation, and can be designed by engineers using smaller test systems. However, the formation of aerobic granules from non-granular biosolids in continuous flow reactors is not understood. Based on prior research, it is hypothesized that the key to inducing aerobic granulation is not the sequencing batch mode, but the ability of a bioreactor to provide variable shear. This research will test this hypothesis and investigate the mechanistic links between reactor hydrodynamics, microbial responses, and ultimately granulation under aerobic conditions. A combination of approaches, including analysis of microbial morphological changes in a micro-reactor, molecular microbial analysis of populations and genes in lab-scale reactors, and use of computational fluid dynamics and Lagrangian sensors, will be used to show how shear variability is a necessary condition for aerobic granulation. Finally, this research will demonstrate scale up by constructing and operating a continuous-flow pilot-scale reactor to induce aerobic granulation. This combined approach will show how aerobic granular sludge technology can be used to retrofit existing activated sludge plants, potentially providing a significant leap in aerobic treatment technology, and impacting thousands of wastewater treatment plants around the world.The development of aerobic granular biomass reactors has excited the wastewater treatment industry, as it represents an innovative, efficient, compact, and potentially more sustainable method for treating wastewater. Aerobic granular biomass reactors can treat high strength wastewaters containing organics. This project will potentially benefit municipal and industrial wastewater treatment plants including those that perform nutrient removal. Developing aerobic granules in existing wastewater treatment plants represents a leap in technology with economic and efficiency benefits for the nation's wastewater infrastructure. The results from this innovative research will also generate information that can be used in the classroom and foster learning through excitement of discovery.