School of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan 430070, PR China.
School of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan 430070, PR China.
Bioresour Technol. 2022 Jan;343:126066. doi: 10.1016/j.biortech.2021.126066. Epub 2021 Oct 6.
In this study, the fluctuating profiles of physicochemical and microbial characterizations along different filling heights of continuously up-flow solid-phase denitrification (SPD) columns packed with polycaprolactone (PCL) were investigated. It was found both the PCL filling area and non-filling area made significant contributions to treatment performance and denitrification mainly occurred near the bottom of the filling column. Nitrate displayed a high proportional removal (≥98.7%) among all the cases except the one with the lowest filling ratio (FR30) and highest NLR (3.99 ± 0.12 gN/(L·d)), while nitrite and ammonium displayed a weak accumulation in final effluents (nitrite ≤ 0.40 mg/L; ammonium ≤ 0.98 mg/L). The intensity of PCL hydrolysis in the top substrate was stronger than those in the middle or bottom. Both dissimilatory nitrate reduction to ammonium (DNRA) and microbial lysis contributed to ammonium accumulation, and nitrate was mainly removed via traditional denitrification and DNRA. JGI_0000069-P22_unclassified and Gracilibacteria_unclassified might contribute to denitrification.
在这项研究中，研究了连续上流固相反硝化（SPD）柱在不同填充高度下的物理化学和微生物特性的波动情况，这些柱子填充了聚己内酯（PCL）。研究发现，PCL 的填充区域和非填充区域对处理性能都有重要贡献，反硝化主要发生在填充柱的底部附近。在所有情况下，除了填充率最低（FR30）和氮负荷率最高（3.99 ± 0.12 gN/（L·d））的情况下，硝酸盐的去除率都很高（≥98.7%），而亚硝酸盐和铵在最终流出物中积累较弱（亚硝酸盐≤0.40 mg/L；铵≤0.98 mg/L）。顶部基质中 PCL 的水解强度强于中部或底部。异化硝酸盐还原为铵（DNRA）和微生物裂解都导致了铵的积累，而硝酸盐主要通过传统的反硝化和 DNRA 去除。JGI_0000069-P22_unclassified 和 Gracilibacteria_unclassified 可能有助于反硝化。
