Key Laboratory of Clean Utilization Technology for Renewable Energy, Ministry of Agriculture, College of Engineering, China Agricultural University, 100083 Beijing, PR China; College of Agriculture and Environmental Sciences, Makerere University, 7062 Kampala, Uganda.
Department of Bioscience, Aarhus University, Aarhus 8000C, Denmark.
Sci Total Environ. 2017 Aug 15;592:197-205. doi: 10.1016/j.scitotenv.2017.03.125. Epub 2017 Mar 17.
Three types of vertical flow constructed wetland columns (VFCWs), packed with corn cob biochar (CB-CW), wood biochar (WB-CW) and gravel (G-CW) under tidal flow operations, were comparatively evaluated to investigate anaerobic digested effluent treatment performance and mechanisms. It was demonstrated that CB-CW and WB-CW provide significantly higher removal efficiencies for organic matter (>59%), NH-N (>76%), TN (>37%) and phosphorus (>71%), compared with G-CW (22%-49%). The higher pollutants removal ability of biochar-packed VFCWs was mainly attribute to the higher adsorption ability and microbial cultivation in the porous biochar media. Moreover, increasing the flooded/drained ratio from 4/8h to 8/4h of the tidal operation further improved around 10% of the removal of both organics and NH-N for biochar-packed VFCWs. The phosphorus removal was dependent on the media adsorption capacities through the whole experiment. However, the NH-N biodegradation by microbial communities was demonstrated to become the dominant removal mechanism in the long term treatment, which compensated the decreased adsorption capacities of the media. The study supported that the use of biochar would increase the treatment performance and elongate the lifespan of CWs under tidal operation.
三种垂直流人工湿地柱（VFCWs），在潮汐流操作下，分别填充玉米芯生物炭（CB-CW）、木材生物炭（WB-CW）和砾石（G-CW），用于比较研究厌氧消化出水的处理性能和机制。结果表明，与 G-CW（22%-49%）相比，CB-CW 和 WB-CW 对有机物（>59%）、NH-N（>76%）、TN（>37%）和磷（>71%）的去除效率显著提高。生物炭填充 VFCWs 的较高污染物去除能力主要归因于多孔生物炭介质中较高的吸附能力和微生物培养。此外，增加潮汐操作的充水/排水比从 4/8h 增加到 8/4h，进一步提高了生物炭填充 VFCWs 对有机物和 NH-N 的去除率约 10%。磷的去除取决于整个实验过程中介质的吸附能力。然而，微生物群落的 NH-N 生物降解被证明是长期处理的主要去除机制，这弥补了介质吸附能力的下降。该研究支持在潮汐操作下使用生物炭可以提高 CWs 的处理性能并延长其使用寿命。
