Pollutant removal employing tidal flow constructed wetlands: Media and feeding strategies
Pollutant removal employing tidal flow constructed wetlands: Media and feeding strategies
复制标题
DOI：
10.1016/j.cej.2019.122874
复制
发表时间：
2020-02
影响因子：
15.1
通讯作者：
Tanveer Saeed;Jihad Miah;T. Khan;Ahasanul Ove
中科院分区：
文献类型：
--
作者：
Tanveer Saeed;Jihad Miah;T. Khan;Ahasanul Ove
研究了6种部分饱和和非饱和潮汐流人工湿地对城市污水中氮、磷和有机物的去除效果。TFCW内填充有机物（生物炭、煤、椰泥炭）、废弃物（矿渣）、建筑材料（砾石、混凝土砌块），并种植芦苇或香根草。实验分析表明，有机介质为基础的TFCW（71-85%和84- 96%，分别），更高的氮和有机物的去除率相比，废物，建筑材料为基础的单位（49-69%和74- 95%，分别）;有机材料的碳可用性增加反硝化，也支持能量色散光谱（EDS）分析。建筑材料和废弃物基TFCW具有更好的除磷效果（≥93%）;此类材料的Ca/Al/Fe成分允许通过吸附去除P。介质内废水接触时间的增加触发了物理化学和微生物去除途径。部分饱和煤填充TFCW是最有效的单位在氮去除率方面;存在的固定水量创造缺氧环境，减少输入负荷，从而提高去除性能。在去除率（g/m2 d）方面，不饱和TFCWs表现出更高的去除（超过部分饱和单元），这可能与更大的输入负荷。质量平衡分析表明，≤3%的N去除通过植物吸收，植物种类的变化没有影响N去除。因此，观察到的去除动力学是由吸附和微生物途径。本研究的结果表明，投料子循环可以提高TFCW中的污染物去除时，填充特定的媒体。
Six partially saturated and unsaturated tidal flow constructed wetlands (TFCWs) were studied for the removal of nitrogen, phosphorus and organics from municipal wastewater. The TFCWs were packed with organic (biochar, coal, coco-peat), waste (slag), construction (gravel, concrete block) materials and planted withPhragmitesorVetiver.Daily wastewater feeding cycle was divided into sub-cycles across all TFCWs. Experimental analyses illustrated higher nitrogen and organics removals in organic media based TFCWs (71–85% and 84–96%, respectively), when compared with those of waste, construction material based units (49–69% and 74–95%, respectively); carbon availability from organic materials increased denitrification that was also supported by energy dispersive spectroscopy (EDS) analyses. Construction and waste material based TFCWs achieved better P removals (≥93%); Ca/Al/Fe ingredients of such materials allowed P removal via adsorption. Increment of wastewater contact period inside the media triggered physico-chemical and microbial removal routes. Partially saturated coal packed TFCW was the most efficient unit in terms of N removal percentage; presence of stationary water volume created anoxic environment and reduced input load, thereby improving removal performances. In terms of removal rates (g/m2d), unsaturated TFCWs showed higher removal (over partially saturated units), which could be linked with greater input load. Mass balance analyses indicated ≤3% N removal through plant uptake; variation of plant species did not influence N removal. Therefore, observed removal kinetics was governed by adsorption and microbial routes. The results of this study suggest that, feeding sub-cycles could improve pollutant removals in TFCWs when packed with specific media.