Sequential application of soil vapor extraction and bioremediation processes for the remediation of ethylbenzene-contaminated soils

摘要

Soil vapor extraction (SVE) is an efficient,well-known and widely applied soil remediation technology.However, under certain conditions it cannotachieve the defined cleanup goals, requiring furthertreatment, for example, through bioremediation (BR).The sequential application of these technologies ispresented as a valid option but is not yet entirelystudied. This work presents the study of the remediationof ethylbenzene (EB)-contaminated soils, with differentsoil water and natural organic matter (NOMC) contents,using sequential SVE and BR. The obtained resultsallow the conclusion that: (1) SVE was sufficient toreach the cleanup goals in 63% of the experiments (allthe soils with NOMC below 4%), (2) higher NOMCsled to longer SVE remediation times, (3) BR showed tobe a possible and cost-effective option when EB concentrationswere lower than 335 mg kgsoil−1, and (4)concentrations of EB above 438 mg kgsoil−1 showed tobe inhibitory for microbial activity.