Electroremediation of a natural soil polluted with phenanthrene in a pilot plant

Abstract

In this work, a pilot plant with two rows of three electrodes in semipermeable electrolyte wells was used to study the electrokinetic treatment of a natural soil polluted with phenanthrene (PHE). The electrokinetic pilot plant was an open system, i.e., there was direct contact between the soil and air. To increase the solubility of phenanthrene, thereby enhancing its transport through the soil, an aqueous solution of the anionic surfactant dodecyl sulfate was used as a flushing fluid. The results show that at the pilot scale considered, gravity and evaporation fluxes are more relevant than electrokinetic fluxes. Contrary to observations at the laboratory scale, desorption of PHE promoted by electric heating appears to be a significant removal mechanism at the pilot scale. In addition, PHE is dragged by the electroosmotic flow in the cathodic wells and by electrophoresis after interaction of the surfactant with phenanthrene in the anodic wells. In spite of the long treatment time (corresponding to an energy consumption over 500kWhm(-3)), the average removal attained was only 25%.

Dielectric barrier discharge plasma used as a means for the remediation of soils contaminated by non-aqueous phase liquids

“…For the abatement of soil pollution by NAPLs, various soil remediation methods have been proposed: thermal desorption, bioremediation, chemical flushing and soil vapor extraction [2][3][4][5][6][7]. The efficiency of these methods is commonly controlled by a broad http variety of parameters related with the pore space properties of soils (e.g.…”

Electro-assisted groundwater bioremediation: Fundamentals, challenges and future perspectives

“…Significantly accelerated degradation of diesel hydrocarbon in a bio-PRB by electrochemical stimulation (29% versus 12% removal within two weeks) under an applied power density of 66 kW h/m 3 was also demonstrated (Ramírez et al, 2015a) (Table 1). In comparison, only 25% phenanthrene removal was attained in a sole electrokinetic system with an energy consumption of 500 kW h/m 3 after three months (López-Vizcaíno et al, 2014).…”

“…Application of an electrode lead to electroosmotic flux through the soil pore and enhance the contaminant desorption and degradation (Pazos et al, 2010). However, such approaches are insufficient to drive the mobilization of other organics such as diesel (López-Vizcaíno et al, 2014).…”

Performance of electroremediation in real contaminated sediments using a big cell, periodic voltage and innovative surfactants

“…Considering its numerous applications both in the laboratory [32][33][34][35][36] as well as any attempt of pilot scale or scaling up [4,5,[37][38][39][40], EK appears to be one of the most sufficient and cost-effective alternatives for treating, even, real sediments (dredged or surficial) which often come with the simultaneous presence of multiple contaminants which interact with the constituents of solid matrices, thereby creating other compounds that limit and/or incommode even more the EK process. However, when all contaminants and/or substances are dissolved, they are, then, easily transported (flushed) into the electrolyte chambers, thus obtaining their desirable removal from the polluted soil/sediment sample.…”