|
International Journal of Environment Science and Technology
Center for Environment and Energy Research and Studies (CEERS)
ISSN: 1735-1472 EISSN: 1735-1472
Vol. 12, No. 3, 2015, pp. 1011-1020
|
Bioline Code: st15093
Full paper language: English
Document type: Research Article
Document available free of charge
|
|
International Journal of Environment Science and Technology, Vol. 12, No. 3, 2015, pp. 1011-1020
en |
Non-aqueous phase liquid-contaminated soil remediation by ex situ dielectric barrier discharge plasma
Aggelopoulos, C. A.; Tsakiroglou, C. D.; Ognier, S. & Cavadias, S.
Abstract
Non-thermal dielectric barrier discharge
plasma is examined as a method for the ex situ remediation
of non-aqueous phase liquid (NAPL)-contaminated soils. A
mixture of equal mass concentrations (w/w) of n-decane, ndodecane
and n-hexadecane was used as model NAPL.
Two soil types differing with respect to the degree of
micro-heterogeneity were artificially polluted by NAPL: a
homogeneous silicate sand and a moderately heterogeneous
loamy sand. The effect of soil heterogeneity, NAPL
concentration and energy density on soil remediation efficiency
was investigated by treating NAPL-polluted samples
for various treatment times and three NAPL
concentrations. The concentration and composition of the
residual NAPL in soil were determined with NAPL
extraction in dichloromethane and GC-FID analysis, while
new oxidized products were identified with attenuated total
reflection Fourier transform infrared spectroscopy (ATRFTIR).
The experimental results indicated that the overall
NAPL removal efficiency increases rapidly in early times
reaching a plateau at late times, where NAPL is removed
almost completely. The overall NAPL removal efficiency
decreases with its concentration increasing and soil heterogeneity
strengthening. The removal efficiency of each
NAPL compound is inversely proportional to the number
of carbon atoms and consistent with alkane volatility. A
potential NAPL degradation mechanism is suggested by
accounting for intermediates and final products as quantified
by GC-FID and identified by ATR-FTIR.
Keywords
Dielectric barrier discharge; Non-aqueous phase liquid removal efficiency; Plasma oxidation; Soil heterogeneity; Soil remediation
|
|
© Copyright 2013 - Islamic Azad University Alternative site location: http://www.ijest.org
|
|