CAREER: Fundamental Studies of Cross-Kingdom Aggregate Biofilms for Energy-Efficient Wastewater Treatment

1452613 ButlerCAREER：跨王国聚合生物膜用于节能废水处理的基础研究随着处理要求的日益严格，废水处理正变得越来越能源密集型。一种被称为藻泥颗粒处理的过程使用了较大的颗粒，这些颗粒可以从废水中分离出来，由于它们的大小，更容易沉淀。与许多基于藻类的废水处理系统相比，建议的工艺占用的处理足迹更小，并有可能被用作生物能源原料。这一过程的优点使其成为一种值得采用的二级治疗方法。然而，这一新的过程仍处于早期开发阶段，需要更多的知识来了解这些跨王国颗粒生物膜的聚集和功能。PI将与克拉克听力和言语学校的一名教师合作，培养听力障碍学生的技术素养，使用藻泥颗粒的高度视觉成分来教授质量平衡、环境污染以及水和废水处理的概念。在赠款期间，每年可有多达60名本科生(总计300人)参加新的基于项目的学习，500多名听障学生有可能接触到环境工程课程。这项研究将展示：1)初始颗粒化的机制，2)不同颗粒形态的结构完整性以及物理特征与性能和微生物生态的关系，以及3)藻泥颗粒在压力条件下的弹性。在发现藻泥颗粒之前，在处理系统中使用同时培养微藻和细菌的颗粒是史无前例的。在环境中很少观察到大颗粒的光养生物和细菌。这项研究是对一个独特的微生物系统的特征和性能的调查，其中真核生物和原核生物通过共生而存在。这一基础性研究将提高对生物膜聚合体中跨界微生物相互作用的理解，也将为推动一种有前途的处理技术的实施提供有价值的信息。在初始颗粒形成的时间点，将通过将群体感应信号分子和卵磷脂蛋白的表达与溶解氧浓度相关联来研究细菌和光养生物的协调。通过观察颗粒形态并测量它们在纳米压缩仪器施加的物理应力下的屈服强度，将记录三种常见藻泥颗粒的物理特征。将通过基于DNA的分子技术和不同藻泥颗粒表型在小试反应器中的表现来研究藻泥的物理特性与微生物生态的关系。功能冗余和扩散阻力导致藻泥颗粒在压力条件下的弹性，通过使用液体离子交换和安培微传感器研究化学通量，并将处理性能的任何变化与微生物生态的变化相关联将被证明。由此产生的数据将建立有助于接种、操作和验证藻泥颗粒处理的知识，推动藻泥颗粒工艺的实施。这项研究还将在满足废水目标的情况下确定光养生物和细菌之间的关系，这在很大程度上还没有得到探索。

1452613ButlerCAREER: Fundamental Studies of Cross-Kingdom Aggregate Biofilms for Energy-Efficient Wastewater TreatmentWastewater treatment is becoming increasingly energy-intensive as treatment requirements become more stringent. A process known as Algal-Sludge Granule treatment uses larger particles which can be separated from the wastewater and, because of their size, settle more easily. The proposed process would occupy a smaller treatment footprint than many algae-based wastewater treatment systems and has the potential to be used as a bioenergy feedstock. The merits of this process make it compelling for adoption as a secondary treatment approach. However, this novel process is still in the early stages of development and much more knowledge is needed to understand the aggregation and function of these cross-kingdom granular biofilms. The PI will work with a teacher from the Clarke Schools for Hearing and Speech to build technical literacy in hearing-impaired students, using the highly visual components of Algal-Sludge Granules to teach concepts of mass-balance, environmental contamination and water and wastewater treatment. During the grant period as many as 60 undergraduates per year (300 total) could participate in new project-based learning and there is potential for more than 500 hearing-impaired students to gain exposure to environmental engineering curricula. This proposed research will demonstrate: 1) the mechanisms of initial granulation, 2) the structural integrity of different granule morphologies and how physical characteristics relate to performance and microbial ecology, and, 3) the resiliency of Algal-Sludge Granules under conditions of stress. Before the discovery of Algal-Sludge Granules, using granules cultivated with both microalgae and bacteria in treatment systems was unprecedented. Large granules of phototrophs and bacteria are rarely observed in the environment. This study is an investigation of the characteristic and performance of a unique microbiological system where eukaryotes and prokaryotes exist through symbioses. This fundamental investigation will improve the understanding of cross-kingdom microbial interactions in a biofilm aggregate but also provide valuable information to advance a promising treatment technology towards implementation. At the point of initial granulation, the coordination of bacteria and phototrophs, by correlating the expression of quorum-sensing signaling molecules and lecithin proteins with dissolved oxygen concentrations, will be studied. The physical characteristics of three common Algal-Sludge Granule phenotypes by observing granule morphologies and measuring their yield strength in response to physical stresses imposed by a nano-compression instrument will be documented. The relation of the physical characteristics to microbial ecology through DNA-based molecular techniques and performance of different Algal-Sludge Granule phenotypes in bench-scale reactors will be studied. The functional redundancy and diffusion resistance leads to Algal-Sludge Granule resiliency under conditions of stress by investigating chemical fluxes using liquid-ion exchange and amperometric microsensors and correlating any changes in treatment performance to shifts microbial ecology will be demonstrated. The resulting data will build knowledge that will help inoculate, operate and validate Algal-Sludge Granule treatment, advancing Algal-Sludge Granule process toward implementation. This study will also define the relationships between phototrophs and bacteria in the context of meeting wastewater objectives, which until now is largely unexplored.