Manhattan College, Department of Civil and Environmental Engineering, 4513 Manhattan College Parkway Riverdale, NY 10471, USA.
Hazen and Sawyer, 4035 Ridge Top Road, Suite 400, Fairfax, VA 22030, USA.
Sci Total Environ. 2020 Jul 1;724:138283. doi: 10.1016/j.scitotenv.2020.138283. Epub 2020 Mar 28.
Nitrogen removal from wastewater is an energy and chemical intensive process that is becoming increasingly more common around the world. To address the cost and complexity issues associated with biological nitrogen removal from wastewater, an alternative approach for achieving next generation nitrogen removal via partial nitrification, denitratation and anaerobic ammonia oxidation (PANDA) has been developed. The PANDA process relies on converting 50% of influent ammonia load to nitrate via aerobic ammonia (AerAOB) and nitrite oxidizing bacteria (NOB). The nitrate is reduced to nitrite (denitratation), followed by the removal of ammonia and nitrite by heterotrophic denitrifiers and anaerobic ammonia oxidizing biomass (AnAOB). Results from a pilot-scale sidestream PANDA demonstration at nitrogen loadings of 0.2-0.25 kg N/m-day illustrated that up to 80% ammonia removal could be achieved. Testing in the mainstream process at initial ammonia concentrations of ~25 mg N/L indicated that 90% removal of total inorganic nitrogen could be achieved and that nitrogen removal was ultimately dependent on operating factors including aeration time, supplemental carbon dosing, hydraulic retention time and nitrate concentrations. Results cumulatively indicated that there was inherent resiliency within the PANDA systems when responding to variable environmental and operational conditions. This is hypothesized to be due to the fact that nitrogen removal is due to the combined synergistic activity of AerAOB, NOB, heterotrophic denitrifiers and AnAOB. Accordingly, utilization of PANDA based treatment processes may allow Water Resource Recovery Facilities (WRRFs) to achieve more sustainable and cost effective nitrogen removal in sidestream and mainstream processes without the need for NOB suppression and complex operational controls.
从废水中去除氮是一个能源和化学密集型过程，在世界范围内变得越来越普遍。为了解决从废水中生物去除氮的成本和复杂性问题，已经开发出一种通过部分硝化、反硝化和厌氧氨氧化（PANDA）实现下一代氮去除的替代方法。PANDA 工艺依赖于通过好氧氨（AerAOB）和亚硝酸盐氧化菌（NOB）将 50%的进水氨负荷转化为硝酸盐。硝酸盐被还原为亚硝酸盐（反硝化），然后通过异养反硝化菌和厌氧氨氧化生物量（AnAOB）去除氨和亚硝酸盐。在氮负荷为 0.2-0.25kgN/m-天的侧流 PANDA 示范的中试规模结果表明，氨的去除率高达 80%。在初始氨浓度约为 25mgN/L 的主流工艺中的测试表明，总无机氮的去除率可达到 90%，并且氮的去除最终取决于操作因素，包括曝气时间、补充碳源投加、水力停留时间和硝酸盐浓度。结果表明，PANDA 系统在应对多变的环境和操作条件时具有内在的弹性。这被假设是由于氮去除是由于 AerAOB、NOB、异养反硝化菌和 AnAOB 的协同活性。因此，利用基于 PANDA 的处理工艺可以使水资源回收设施（WRRF）在侧流和主流工艺中实现更可持续和更具成本效益的氮去除，而无需抑制 NOB 和复杂的操作控制。
