CAREER: Microbial Storage Products and Density: Overlooked Fundamentals and Promising Opportunities in Biological Solids Separation

舒拉提出了一个全面的五年计划，用于创新研究项目和补充教育计划。这项研究的动机是，生物废水处理系统中固体沉淀过程的改进可能会带来环境和人类健康保护和成本节约的巨大好处，而且人们注意到，影响沉淀的一个基本但潜在的关键因素(密度)几乎没有研究过。有效的生物固体沉淀是至关重要的，必须提供澄清的污水和浓缩的固体流，以供系统循环和废物使用。驱动所有沉降过程的重力是浮力密度(液体和固体密度之差)的函数。虽然生物质的浮力密度可以有很大的变化，但可以提出新的、有效的策略来改进基于密度优化的固体分离。这是基于以下观察结果：(1)高密度微生物存储产品(MSP)浓度在处理系统中有所不同，(2)MSP积累影响细菌密度，(3)先前的报告表明，选择MSP积累微生物的系统改善了与细丝控制无关的沉降。此外，在初步实验中，MSPS、密度和沉降量之间的相关性与预期一致。絮体大小和细丝含量等因素明显影响沉降速率，目前的假设表明，生物质密度可能是一个额外的、基本的、以前被忽视的因素，在分析和控制生物质沉降时应该考虑到这一因素。这项建议的主要目标是产生和验证一个将工艺参数、密度和沉降量联系起来的模型。这将需要确定操作参数与MSP积累(以及影响密度的其他因素)之间的关系，这些因素与密度之间的关系，以及密度与沉降性之间的关系。这项工作的更广泛的影响包括：加强对环境和人类健康的保护，并通过提高工艺性能来节省成本；更好地了解MSP，它普遍存在于自然和工程系统中，但并不总是被很好地理解；提高对生物除磷过程和好氧MSP积累的理解；增加科学中代表性不足的群体的代表；改进高中课程；在本科生和研究生中发展高级实验室和建模技能。

0348594SchulerA comprehensive five-year plan is proposed for an innovative research project and a complementary educational program. The research is motivated by the large benefits in increased environmental and human health protection and cost savings, which may result from improvements to solids settling processes in biological wastewater treatment systems, and the observation that a fundamental yet potentially critical factor (density) affecting settling has been scarcely studied. Efficient biosolids settling is vital the provision of a clarified effluent and a concentrated solids stream for system recycling and wasting. The gravitational force that drives all settling processes is a function of buoyant density (the difference between liquid and solid densities). It is hypothesized that although biomass buoyant density can vary substantially, and that new, effective strategies can be developed to improve solids separation based on density optimization. This is based on observations that (1) high-density microbial storage product (MSP) concentrations vary in treatment systems, (2) MSP accumulation affects bacterial density, and (3) previous reports indicate systems selecting for MSP-accumulating organisms improve settling independently of filament control. Furthermore, MSPs, density, and settling were correlated as expected in preliminary experiments. Factors such as floc size and filament content clearly affect settling rates, and the current hypothesis suggests that biomass density may be an additional, fundamental, and previously neglected factor that should be considered in the analysis and control of biomass settling. A governing objective of this proposal is to produce and validate a model linking process parameters, density, and settling. This will require determination of the relationships between operational parameters and MSP accumulation (and other factors affecting density), between these factors and density, and between density and settleability. The broader impacts of this work include increased protection of environmental and human health and costs saving through increased process performance; development of a better understanding MSPs, which are ubiquitous in natural and engineered systems but not always well-understood; improved understanding of biological phosphorus removal processes and aerobic MSP accumulation; increased representation of underrepresented groups in the sciences; improved high school curricula; and development of advanced laboratory and modeling skills in undergraduate and graduate students.