Phytoremediation of arsenic- and molybdenum-contaminated alkaline wastewater by Eleocharis acicularis in winter in Japan

2nd Transdisciplinary Research on Environmental Problems in Southeast Asia

地球科学;生态环境科学

Yamazaki, Shusaku^1 ; Okazaki, Kenji^1 ; Kurahashi, Toshiyuki^1 ; Sakakibara, Masayuki^2

Civil Engineering Research Institute for Cold Region, Public Works Research Institute, National Research and Development Agency, 1-34, Hiragishi 1-3, Toyohira-ku, Hokkaido, Sapporo

062-8602, Japan^1

Graduate School of Science and Engineering, Ehime University, 0-13, Dogo-Himata, Matsuyama, Ehime

790-8577, Japan^2

关键词: Alkaline environment;    Alkaline wastewater;    Low temperatures;    Low-cost measures;    Marine sediments;    Mo concentration;    Remediation methods;    Toxic heavy metals;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/71/1/012018/pdf
DOI  :  10.1088/1755-1315/71/1/012018

学科分类：环境科学（综合）

来源: IOP

【 摘 要 】

Phytoremediation using aquatic plants is a sustainable, low-cost measure for remediating water contaminated by toxic heavy metals. In this study, we conducted a channel experiment using Eleocharis acicularis in heavy metal-contaminated mildly alkaline wastewater under unfavorable plant habitat conditions in winter in northeastern Japan. The wastewater from an embankment consisting of Neogene marine sediments had a temperature of 10-15 °C and a pH of about 9, and it contained ∼0.02 mg/L of As and ∼ 0.23 mg/L of Mo. About 16 kg (fresh weight) of E. acicularis was laid in a plastic channel measuring 30 cm in width by 20 m in length, and the channel was enclosed in a tunnel greenhouse. The experiment was conducted for the 3 months from November 2015 at an average flow rate of 0.3 L/min and an air temperature of -4 to 19 °C. No reductions in As or Mo concentrations in the outflow were detected. However, at 3 months, the E. acicularis showed accumulations of ∼7 mg/kg As and ∼18 mg/kg Mo as dry weight, indicating that this remediation method is workable in an unfavorable low-temperature, mildly alkaline environment.