Centre for Water Resources Research, School of Civil, Structural and Environmental Engineering, University College Dublin, Newstead Building, Belfield, Dublin 4, Ireland.
Bioresour Technol. 2012 May;111:27-35. doi: 10.1016/j.biortech.2012.01.165. Epub 2012 Feb 6.
Step-feeding strategies have been extensively studied and comprehensively analyzed in this study for a four-stage alum sludge-based tidal flow constructed wetlands (AlS-TFCWs) system. Enhanced total nitrogen removal of 83% is achieved under high nitrogen loading rate of 19.1 g N/m(2)d. The key issues towards the success of a significant nitrogen removal in step-feeding TFCWs are the bed resting time (which provides better aeration for nitrification) and up flow stage/delayed input of side stream(s) (which ensure favorable environment for better denitrification). Simultaneous nitrification and denitrification (SND) was found effective in the 1st stage of the system and SND via nitrite is the main nitrogen conversion mechanism. The optimal influent distribution fraction for step-feeding purpose can be estimated from a theoretical basis, which is a function of the influent BCOD/TKN ratio. Therefore the influent distribution fraction should be adjusted according to the variety of influent characteristics, rather than a fixed value.
在本研究中，针对四级铝污泥潮汐流人工湿地（AlS-TFCWs）系统，广泛研究并综合分析了阶跃进料策略。在 19.1 g N/m(2)d 的高氮负荷率下，实现了增强的总氮去除率 83%。在阶跃进料 TFCWs 中实现显著脱氮的关键问题是床休息时间（为硝化提供更好的曝气）和上流阶段/侧流（side stream）延迟输入（确保更好的反硝化的有利环境）。发现系统第一阶段的同时硝化反硝化（SND）有效，亚硝酸盐途径的 SND 是主要的氮转化机制。对于阶跃进料目的的最佳进水分配分数可以从理论基础上进行估计，这是进水 BCOD/TKN 比的函数。因此，根据进水特性的变化，而不是固定值，应该调整进水分配分数。
