Comparison of heavy metal removal efficiencies infour activated sludge processes
来源期刊:中南大学学报(英文版)2015年第10期
论文作者:YANG Jun GAO Ding CHEN Tong-bin LEI Mei ZHENG Guo-di ZHOU Xiao-yong
文章页码:3788 - 3794
Key words:wastewater; heavy metal; removal efficiency; treatment process; activated sludge processes
Abstract: The removal efficiencies of heavy metals (As, Cr, Cu, Ni, Pb and Zn) were investigated in the 17 operating municipal wastewater treatment plants (WWTPs) and compared with those in four main activated sludge processes. Significant differences of heavy metal removal efficiencies were observed among four activated sludge processes. The removal efficiency for As (75.5%) in the oxidation ditch (OD) process is significantly higher than that in the conventional activated sludge (CAS) process (38.6%) or sequencing batch reactor (SBR) process (51.4%). The mean removal efficiencies for Cu and Ni in the OD process are 90.5% and 46.7%, respectively, while low mean removal efficiencies are observed for Cu (69.9%) and Ni (16.5%), respectively, in the SBR process. The removal efficiencies for Cu and Ni in the OD process are significantly higher than those in the anaerobic-anoxic-oxic (A2-O) process. These results highlight the differences of removal efficiencies for heavy metals in different processes and should be considered when selecting a wastewater treatment process.
YANG Jun(杨军), GAO Ding(高定), CHEN Tong-bin(陈同斌), LEI Mei(雷梅), ZHENG Guo-di(郑国砥), ZHOU Xiao-yong(周小勇)
(Center for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research,
Chinese Academy of Sciences, Beijing 100101, China)
Abstract:The removal efficiencies of heavy metals (As, Cr, Cu, Ni, Pb and Zn) were investigated in the 17 operating municipal wastewater treatment plants (WWTPs) and compared with those in four main activated sludge processes. Significant differences of heavy metal removal efficiencies were observed among four activated sludge processes. The removal efficiency for As (75.5%) in the oxidation ditch (OD) process is significantly higher than that in the conventional activated sludge (CAS) process (38.6%) or sequencing batch reactor (SBR) process (51.4%). The mean removal efficiencies for Cu and Ni in the OD process are 90.5% and 46.7%, respectively, while low mean removal efficiencies are observed for Cu (69.9%) and Ni (16.5%), respectively, in the SBR process. The removal efficiencies for Cu and Ni in the OD process are significantly higher than those in the anaerobic-anoxic-oxic (A2-O) process. These results highlight the differences of removal efficiencies for heavy metals in different processes and should be considered when selecting a wastewater treatment process.
Key words:wastewater; heavy metal; removal efficiency; treatment process; activated sludge processes