Department of Civil & Environmental Engineering, University of South Florida, 4202 E. Fowler Ave, ENG 030, Tampa, FL 33620, USA.
Department of Civil & Environmental Engineering, University of South Florida, 4202 E. Fowler Ave, ENG 030, Tampa, FL 33620, USA.
Bioresour Technol. 2020 Aug;310:123428. doi: 10.1016/j.biortech.2020.123428. Epub 2020 Apr 22.
Bioretention systems improve stormwater infiltration and water quality; however, limited total nitrogen (TN) and fecal indicator bacteria (FIB) removal is observed in sand-based bioretention media. In this study, the fate of nitrogen and E. coli in bioretention systems was investigated through batch and column studies using sand media, with and without biochar addition. Variables investigated included biochar characteristics, hydraulic loading rate (HLR) and antecedent dry period (ADP). Total ammonia nitrogen (TAN), dissolved organic carbon (DOC), and E. coli removals were significantly higher in biochar-amended columns due to biochar's high cation exchange capacity and specific surface area. TAN adsorption resulted in increased nitrification during the ADP when aerobic conditions developed. Moisture content data revealed that saturated conditions prevailed toward the bottom of biochar-amended columns for several days, favoring denitrification and TN removal. Biochar amended columns also showed more stable TAN, DOC and E. coli effluent concentrations under varying HLR and ADP.
生物滞留系统可提高雨水渗透和水质；然而，在沙基生物滞留介质中观察到总氮（TN）和粪大肠菌群（FIB）的去除量有限。在这项研究中，通过使用带有和不带有生物炭添加的沙质介质进行批量和柱研究，调查了氮和大肠杆菌在生物滞留系统中的归宿。研究的变量包括生物炭特性、水力负荷率（HLR）和前期干燥期（ADP）。由于生物炭具有高阳离子交换能力和比表面积，添加生物炭的柱子中的总氨氮（TAN）、溶解有机碳（DOC）和大肠杆菌去除率显著更高。在有氧条件形成期间，ADP 期间 TAN 的吸附导致硝化作用增加。水分含量数据表明，在生物炭添加柱的底部几天内一直处于饱和状态，有利于反硝化和 TN 去除。在不同的 HLR 和 ADP 下，添加生物炭的柱子也显示出更稳定的 TAN、DOC 和大肠杆菌出水浓度。
