New technologies for wastewater resource recovery by anoxigenic photoheterotrophic biological processes

缺氧光异养生物过程废水资源化新技术

• 批准号: RGPIN-2016-06498
• 负责人: Frigon, Dominic
• 金额: $ 2.4万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=651203
• 关键词: New; technologies; wastewater; resource; recovery

Tightening regulations on biosolids disposal and growing energy utilization increase the operational costs of wastewater treatment plants, and reduce the sustainability of municipal infrastructures. In response, the wastewater industry is converting from only treating wastewater for environmental protection to additionally recovering resources wasted with the water. In terms of energy content, recoverable organics and nutrients (nitrogen, phosphorus) account for ~15% of the per capita electricity consumption; accordingly, recovery will improve sustainability and reduce CO2 footprint. However, recovery using current aerobic biological processes is limited. Thus, the current program will contribute to the development of new anaerobic biological processes enabling recovery. The results will improve infrastructure efficiencies and reduce burden to tax payers.******Anaerobic processes pose challenges for Canada because many wastewater facilities operate below 12°C for periods of up to 6 months. Indeed, anaerobic microbes typically have lower maximum growth rates than aerobic ones, resulting in lower process stability and capacity to meet discharge regulations at low temperatures. Additionally, municipal wastewater is relatively dilute for nutrient recovery, and biological concentration is necessary prior to physico-chemical extractions. We propose to use purple non-sulfur bacteria (PNSB) to address these challenges. Their ability to simultaneously obtain energy from light and carbon from organics provides them with higher biomass yields and faster growth rates than other anaerobes. Consequently, high biomass yields make them suitable for concentration of nutrients in biomass, and high growth rates reduce their sensitivity to colder operation temperatures. Finally, because they are the only photosynthetic organisms utilizing infrared light (>800 nm), engineers would possess powerful selection tools to control microbial communities in mixed open cultures.*******Published studies mainly focused on pure culture PNSB wastewater processes and operation at 20-35°C. These conditions are inapplicable to full-scale Canadian municipal wastewater facilities; thus, significant knowledge gaps persist in developing PNSB processes. Additionally, reactor conditions need to be tightly controlled such that metabolism maximizes biomass yields instead of competing H2 and polyhydroxyalkanoate syntheses. This proposal will investigate operation conditions of non-sterile PNSB photobioreactors that are relevant to Canada for enabling implementation of wastewater resource recovery. Furthermore, control strategies for PNSB metabolism and microbial community composition will be developed by using genome-scale metabolic modeling and high-throughput metagenomic molecular tools. The program will train 2 PhD, 4 MEng and 10 undergraduate students.***

生物固体处理法规的收紧和能源利用的不断增长增加了废水处理厂的运营成本，并降低了市政基础设施的可持续性。为此，废水行业正在从仅处理废水以实现环境保护转变为额外回收废水中浪费的资源。就能源含量而言，可回收的有机物和营养物（氮、磷）约占人均电力消耗的 15%；因此，回收将提高可持续性并减少二氧化碳足迹，但是，使用当前的好氧生物进行回收。因此，当前的计划将有助于开发新的厌氧生物工艺，从而实现回收，其结果将提高基础设施效率并减轻纳税人的负担。******厌氧工艺给加拿大带来了挑战，因为许多废水。事实上，厌氧微生物的最大生长速率通常低于需氧微生物，导致工艺稳定性和满足低温下排放法规的能力较低。废水对于营养物回收来说相对稀释，并且在物理化学提取之前需要进行生物浓缩，我们建议使用紫色非硫细菌（PNSB）来解决这些挑战，它们能够同时从光和有机物中获取能量。它们比其他厌氧菌具有更高的生物量产量和更快的生长速率，高生物量产量使它们适合生物量中的营养物质浓缩，并且高生长速率降低了它们对较冷操作温度的敏感性。仅利用红外光 (>800 nm) 的光合生物，工程师将拥有强大的选择工具来控制混合开放培养物中的微生物群落。********已发表的研究主要集中于纯培养 PNSB 废水处理和 20-35 的运行°C。这些条件不适用于全规模的加拿大市政污水处理设施；因此，在开发 PNSB 工艺方面仍然存在重大知识差距，因此需要严格控制反应器条件，以便最大限度地提高生物量产量。该提案将研究与加拿大相关的非无菌 PNSB 光生物反应器的运行条件，以实现废水资源回收。此外，将利用基因组规模制定 PNSB 代谢和微生物群落组成的控制策略。该项目将培训 2 名博士生、4 名硕士生和 10 名本科生。***