A laboratory feasibility study on a new electrokinetic nutrient injection pattern and bioremediation of phenanthrene in a clayey soil.
Electrokinetic (EK) injection has recently been proposed to supply nutrients and electron acceptors in bioremediation of low permeable soils. However, effective pH control and uniform injection of inorganic ions have yet to be developed. The present study investigated a new EK injection pattern, which combined electrolyte circulation and electrode polarity reversal on a clayey soil. Soil pH could be controlled ranging from 7.0 to 7.6 by circulating the mixed electrolyte at a suitable rate (800 mL/h in this study) without any buffer. Ammonium and nitrate ions were distributed more uniformly in soil by electrode polarity reversal. The developed electrokinetic injection technology was applied primarily in bioremediation of phenanthrene contaminated soil. Over 80% of the initial 200mg/kg phenanthrene in soil could be removed in 20 d, and greater phenanthrene removal was achieved using electrode polarity reversal. Hence, the present study provides a promising electrokinetic injection technology for bioremediation of contaminated soils.
Xu
Wei
W
MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, PR China. Electronic address: xwei76@tom.com.
Wang
Cuiping
C
MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, PR China.
Liu
Haibin
H
MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, PR China.
Zhang
Zhiyuan
Z
MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, PR China.
Sun
Hongwen
H
MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, PR China. Electronic address: sunhongwen@nankai.edu.cn.
D000538:Aluminum Silicates; D000077215:Clay; D052918:Environmental Restoration and Remediation / Q000379:methods*; D005240:Feasibility Studies; D010616:Phenanthrenes / Q000737:chemistry / Q000302:isolation & purification*; D012989:Soil Pollutants / Q000737:chemistry / Q000302:isolation & purification*
D000538:Aluminum Silicates; D010616:Phenanthrenes; D012989:Soil Pollutants; C031181:phenanthrene; D000077215:Clay