School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, PR China.
School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, PR China.
J Environ Manage. 2022 Nov 15;322:116104. doi: 10.1016/j.jenvman.2022.116104. Epub 2022 Aug 30.
This study investigated the interaction between plant biomass and iron scraps and their influence on nitrogen (including nitrate and ammonia) and phosphorus removal in the subsurface flow constructed wetland. The results showed that with the addition of 0.5 g L of plant biomass and 5.0 g L of iron scraps, the nitrate, total nitrogen and total phosphorus removal were simultaneously improved. During 35 days of continuous operation, the plant biomass played main effect on the enhanced denitrification, accounting for about 57%, while iron scraps enhanced the other 43% of nitrogen removal and most phosphorus removal through precipitation inside the wetlands. Iron scraps could benefit the degradation of cellulose into low molecular carbohydrates by 10%, and the biomass could promote the oxidation of iron and increase the total phosphorus removal by 15%. Plant biomass coupled with iron scraps also improved simultaneously the richness, diversity and evenness of microbial community and promoted the abundance of Nitrospira (17.37%) and Thiobacillus (8.46%) in wetlands. In practice, putting iron scraps as matrix and placing plant biomass in the influent region would be a better choice. This research would provide a new method for effective utilization of plant biomass and iron scraps and further treatment of low-polluted wastewater in the wetlands.
本研究探讨了植物生物质和铁屑之间的相互作用及其对地下流人工湿地中氮（包括硝酸盐和氨）和磷去除的影响。结果表明，添加 0.5 g/L 的植物生物质和 5.0 g/L 的铁屑可以同时提高硝酸盐、总氮和总磷的去除率。在 35 天的连续运行中，植物生物质对增强反硝化作用起主要作用，约占 57%，而铁屑通过湿地内部沉淀增强了另外 43%的氮去除和大部分磷去除。铁屑可以使纤维素降解为低分子碳水化合物的效率提高 10%，而生物质可以促进铁的氧化，使总磷去除率提高 15%。植物生物质与铁屑的结合还可以同时提高微生物群落的丰富度、多样性和均匀度，并促进湿地中 Nitrospira（17.37%）和 Thiobacillus（8.46%）的丰度增加。在实际应用中，将铁屑作为基质并将植物生物质放置在进水区域将是更好的选择。本研究为有效利用植物生物质和铁屑以及进一步处理湿地中低污染废水提供了一种新方法。
