Engineering a better biofilm: Rational design of attachment surface chemistry and morphology to remove nutrients and microconstituents

CBET 1337077新墨西哥州安德鲁·舒勒大学-美国污水处理行业正在努力解决保护敏感接收水不受微量化学物质影响的关键问题，这些化学物质包括药品、激素和工业化学品。由于这些化合物经常被检测到并在极低浓度下对生态系统造成破坏，因此受到越来越多的关注。先进的物理化学处理工艺，如反渗透，可以有效地去除许多此类化学物质，但其能源消耗和环境后果一直受到批评，而且对许多社区来说，它们可能成本高昂。因此，这些污染物的生物降解是有吸引力的，但在如何设计这种系统以实现高水平的性能方面，存在着关键的知识空白。基于生物膜的系统在废水处理系统中的使用越来越多，主要用于脱氮，附着的微生物群落生长在淹没在废水中的塑料表面上。该项目将评估这样一种假设，即通过有针对性地设计附着介质的化学和物理特性，可以“设计”具有特定化学特性的微生物种群、吸光度特性和微生物组分的生物降解率等生物膜特性。初步结果表明，这些特性可以用来生产富含氨氧化细菌(硝化菌)群落的生物膜，还可以提高激素的去除速度。该项目将包括评估特定细菌(例如氨氧化剂和亚硝酸盐氧化剂)在化学定义良好的表面(自组装单层膜)上的微生物附着，对这些相互作用进行建模，以及评估这些表面上的混合培养物。这些结果将被用于开发反应堆系统，在该系统中，使用表面化学来评估表面粗糙度和剪切的附加参数，以确定对功能行为的影响，包括目标微量成分的去除和共代谢活性。该项目将解决可持续去除废水中微量成分的迫切需要，同时提供成本和能源节约。该项目将为如何设计表面以影响生物膜的发育、种群和功能性能提供新的基本见解，这将为利用生物膜系统的工艺工程师产生重要的新设计战略。这些结果对寻求经济有效的技术以减少药物、激素和工业化学品排放到敏感水域的社区应该大有裨益。

CBET 1337077Andrew SchulerUniversity of New MexicoThe U.S. wastewater industry is struggling to solve the critical problem of protecting sensitive receiving waters from microconstituent chemicals, including pharmaceuticals, hormones and industrial chemicals. These compounds are receiving increasing attention due to their frequent detection and their disruption of ecosystems at very low concentrations. Advanced physical-chemical treatment processes, such as reverse osmosis, can be effective at removing many of these chemicals, but their energy consumption and environmental consequences have been criticized, and they can be cost-prohibitive to many communities. Biodegradation of these contaminants is therefore attractive, but there are critical knowledge gaps in how such systems can be designed for high levels of performance. Biofilm-based systems are seeing increasing use in wastewater treatment systems, largely for nitrogen removal, where attached microbial communities are grown on plastic surfaces that are submerged in wastewater. This project will evaluate the hypothesis that biofilm properties, such as microbial populations, absorbance characteristics, and biodegradation rates of microconstituents with specific chemical properties can be "engineered" by targeted design of attachment media chemical and physical characteristics. Preliminary results suggest such properties can be used to produce biofilms with enriched communities of ammonia-oxidizing bacteria (nitrifiers), and also to increase rates of hormone removal. This project will include evaluation of microbial attachment of specific bacteria of interest (e.g., ammonia and nitrite oxidizers) to chemically well-defined surfaces (self-assembled monolayers), modeling of these interactions, and evaluation of mixed cultures on these surfaces. These results will be used to develop reactor systems in which the additional parameters of surface roughness and shear are evaluated, with surface chemistry, to determine effects on functional behaviors, including removal of target microconstituents and cometabolic activity. This project will address the critical need for sustainable microconstituent removal from wastewater, while providing cost and energy savings. The project will provide new, fundamental insights to how surfaces can be designed to influence biofilm development, populations, and functional performance, which should produce important new design strategies for process engineers that utilize biofilm-based systems. These results should be of great use to communities seeking cost-effective technologies to reduce discharges of pharmaceuticals, hormones, and industrial chemicals to sensitive receiving waters.