EAGER: Engineering and Testing a Feammox Bacterium for its use in Nitrogen Removal Bioreactors for Wastewater Treatment

EAGER：设计和测试 Feammox 细菌在废水处理的脱氮生物反应器中的应用

• 批准号: 1433101
• 负责人: Peter Jaffe
• 金额: $ 5万
• 依托单位: Princeton University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-06-01 至 2015-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1433101&HistoricalAwards=false
• 关键词: EAGER; Engineering; Testing; Feammox; Bacterium

1433101JaffeA new pathway for ammonium oxidation coupled to iron reduction in the absence of oxygen and nitrate/nitrite has recently been described by the PI and co-workers for wetland soils in New Jersey, by researchers from UC Berkeley in tropical rainforest soils, and by researchers in Japan in a bioreactor, and has been referred to as Feammox. Further Studies have been conducted in incubations of NJ wetland sediments, confirming that Feammox is a biological process, and that an Acidimicrobiaceae bacterium A6, previously unknown, is responsible for it. Samples have been enriched and the PI has isolated the pure Acidimicrobiaceae bacterium A6 strain. Preliminary results from augmenting an anoxic bioreactor with ferrihydrite and Acidimicrobiaceae bacterium A6 have shown that there is a potential to exploit this process for anaerobic biological ammonium oxidation. Having isolated the Acidimicrobiaceae bacterium A6 raises the potential to determine the functional gene responsible for Feammox and to gain new fundamental insights into this process and its applications.Virtually all wastewater treatment plants in the developed world as well as in many developing countries oxidize ammonia to nitrate ion, before discharging the treated wastewater. This is done to decrease oxygen demand in the receiving waters. Biological ammonium oxidation is conduced by aerobic (in the presence of oxygen) nitrifying bacteria and requires aeration, the step with the highest energy input in wastewater treatment plants. An alternative is the partial nitrification + Anammox system, which has been implemented in some treatment plants over the past 15 years, with the goal of saving energy costs, since only half of the ammonia is converted to nitrite ion aerobically, while the rest is converted to nitrogen gas anaerobically via Anammox. However, these Anammox-based wastewater treatment systems need to operate at temperatures between 28 and 35 Celsius. In contrast, we have shown that the Feammox pathway is still active at below 10 Celsius. Hence, a Feammox-based process could result in further energy savings, by requiring no aeration or heating of the wastewater water in temperate climates, although the cost of an Fe(III) source will have to be taken into account. Furthermore, N excess in near-shore environments has been identified as a major environmental problem leading to eutrophication and anoxia (Chesapeake Bay, Gulf of Mexico, etc.). Therefore legislation is being drafted which will require conversion of nitrate to nitrogen gas in conventional wastewater treatment plants. Potentially the Feammox process could achieve N removal in a single stage reactor with low energy utilization.

最近，PI及其同事在新泽西州的湿地土壤中，加州大学伯克利分校的研究人员在热带雨林土壤中，以及日本的研究人员在生物反应器中描述了一种新的氨氧化与铁还原耦合的途径，该途径被称为Feammox。在新泽西州湿地沉积物的孵育中进行了进一步的研究，证实了Feammox是一个生物过程，并且以前未知的酸化微生物科细菌A6负责。对样品进行富集，PI分离出纯酸化微生物科细菌A6菌株。用铁酸盐和酸性微生物科细菌A6强化厌氧生物反应器的初步结果表明，该工艺有可能用于厌氧生物氨氧化。分离出酸化微生物科细菌A6提高了确定负责Feammox的功能基因的潜力，并对这一过程及其应用获得了新的基本见解。在发达国家和许多发展中国家，几乎所有的污水处理厂在排放处理后的废水之前都将氨氧化成硝酸盐离子。这样做是为了减少接收水域的需氧量。生物氨氧化是由好氧（在氧气存在的情况下）硝化细菌进行的，需要曝气，这是污水处理厂中能量输入最高的步骤。另一种选择是部分硝化+厌氧氨氧化系统，该系统在过去15年中已在一些处理厂实施，其目标是节省能源成本，因为只有一半的氨通过厌氧氨氧化转化为亚硝酸盐离子，而其余的则通过厌氧氨氧化转化为氮气。然而，这些基于厌氧氨氧化的废水处理系统需要在28到35摄氏度之间的温度下运行。相比之下，我们已经证明Feammox途径在低于10摄氏度时仍然具有活性。因此，基于feammox的工艺可以进一步节省能源，因为在温带气候下不需要对废水进行曝气或加热，尽管必须考虑到铁（III）源的成本。此外，近岸环境中的N过量已被确定为导致富营养化和缺氧的主要环境问题（切萨皮克湾，墨西哥湾等）。因此，正在起草立法，要求在传统废水处理厂将硝酸盐转化为氮气。Feammox工艺有可能在低能量利用率的单级反应器中实现脱氮。