Centre for Water Resources Research, School of Civil, Structural and Environmental Engineering, Newstead Building, University College Dublin, Belfield, Dublin 4, Ireland.
Environ Sci Technol. 2012 Apr 17;46(8):4583-90. doi: 10.1021/es204105h. Epub 2012 Mar 28.
A new development on treatment wetland technology for the purpose of achieving high rate nitrogen removal from high strength wastewater has been made in this study. The laboratory scale alum sludge-based intermittent aeration constructed wetland (AlS-IACW) was integrated with predenitrification, intermittent aeration, and step-feeding strategies. Results obtained from 280 days of operation have demonstrated extraordinary nitrogen removal performance with mean total nitrogen (TN) removal efficiency of 90% under high N loading rate (NLR) of 46.7 g N m(-2) d(-1). This performance was a substantial improvement compared to the reported TN removal performance in literature. Most significantly, partial nitrification and simultaneous nitrification denitrification (SND) via nitrite was found to be the main nitrogen conversion pathways in the AlS-IACW system under high dissolved oxygen concentrations (3-6 mg L(-1)) without specific control. SND under high dissolved oxygen (DO) brings high nitrogen conversion rates. Partial nitrification and SND via nitrite can significantly reduce the demand for organic carbon compared with full nitrification and denitrification via nitrate (up to 40%). Overall, these mechanisms allow the system to maintaining efficient and high rate TN removal even under carbon limiting conditions.
本研究针对从高强度废水中实现高氮去除率的目的，对处理湿地技术进行了新的开发。实验室规模的基于铝污泥的间歇曝气人工湿地（AlS-IACW）与预反硝化、间歇曝气和分步进料策略相结合。280 天的运行结果表明，在高氮负荷（NLR）为 46.7 g N m（-2）d（-1）的情况下，具有非凡的氮去除性能，平均总氮（TN）去除效率达到 90%。与文献中报道的 TN 去除性能相比，这一性能有了显著提高。最重要的是，在高溶解氧浓度（3-6 mg L（-1））下，无需特定控制，AlS-IACW 系统中发现通过亚硝酸盐进行部分硝化和同时硝化反硝化（SND）是主要的氮转化途径。高溶解氧（DO）下的 SND 带来了高的氮转化速率。与通过硝酸盐的完全硝化和反硝化相比（高达 40%），通过亚硝酸盐的部分硝化和 SND 可以显著减少对有机碳的需求。总的来说，这些机制允许系统即使在碳限制条件下也能保持高效和高氮去除率。
