Jayaweera M W, Kasturiarachchi J C
Department of Civil Engineering, University of Moratuwa, Sri Lanka.
Water Sci Technol. 2004;50(6):217-25.
This paper elucidates the phytoremediation potential of water hyacinth (Eichhornia crassipes [Mart.] Solms) for TN and TP rich industrial wastewaters determined for 15 weeks under different set-ups of 2-fold (56 TN mg/l and 15.4 TP mg/l), 1-fold, 1/2-fold, 1/4-fold and 1/8-fold and a control with no nutrients in duplicate. A mass balance was conducted to evaluate the phytoremediation efficiencies and to identify the key mechanisms of nutrient removal from the wastewaters. Our results manifested that water hyacinth is a promising candidate for a batch removal of TN and TP from wastewaters. 100% removal of both TN and TP was observed at the end of the 9th week in all the set-ups mainly due to assimilation and the period between 6-9weeks became the optimum period after which complete harvesting is recommended. Plants having an age of 6 weeks are ideal to commence the free-floating wetland and 21 days hydraulic retention time (HRT) is recommended for optimum removal of TN and TP. Assimilation and denitrification were the key mechanisms of TN removal while assimilation and sorption became the prominent mechanisms in the removal of TP from wastewaters.
本文阐述了凤眼莲（Eichhornia crassipes [Mart.] Solms）对富含总氮（TN）和总磷（TP）的工业废水的植物修复潜力，该研究在不同浓度设置下进行了15周，设置包括2倍浓度（56毫克/升TN和15.4毫克/升TP）、1倍浓度、1/2倍浓度、1/4倍浓度、1/8倍浓度以及无营养物质的对照组，每组设置重复两次。通过质量平衡评估植物修复效率，并确定从废水中去除营养物质的关键机制。我们的结果表明，凤眼莲是从废水中分批去除TN和TP的有前景的候选植物。在第9周结束时，所有设置中TN和TP的去除率均达到100%，这主要归因于同化作用，6至9周的时间段成为最佳时期，之后建议进行完全收割。6周龄的植物是启动自由漂浮湿地的理想选择，建议21天的水力停留时间（HRT）以实现TN和TP的最佳去除。同化作用和反硝化作用是去除TN的关键机制，而同化作用和吸附作用则是从废水中去除TP的主要机制。
