Author(s): Adriana Marquez-Romance; Estefania Freytez-Boggio; Julio Maldonado-Maldonado; Samuel Cardenas-Izaguirre; Edilberto Guevara-Perez; Sergio Perez-Pacheco; Eduardo Buroz-Castillo

Linked Author(s):

Keywords: Ex situ bioremediation; In situ bioremediation; Upflow anaerobic filter separate in three-phases; Sequential batch reactor; Slurry sequential batch reactor; Air sparging; Soil vapor extraction

Abstract: The work is focused on testing a new bioremediation method in a tropical aquifer contaminated with hydrocarbons, whose contamination was caused by fuel leaks from underground tanks sited in the area of a fuel service station located in Valencia, Venezuela, sharing boundaries between residential and industrial uses. Ex situ remediation proposal will be developed to laboratory scale. For soil treatment, two coupled bioreactors are proposed consisting of a Soil-Slurry Sequencing Batch Reactor (SS-SBR) and Upflow Anaerobic Filter separated in three phases (UAF-3SS), which will treat soils containing hydrocarbons sorbed in concentration upper to international regulations allowing the occurrence of mass transfer processes to the air (volatilization) present in soil empty spaces in the vadose zone and groundwater (sorption-desorption) in the saturated zone. For groundwater treatment, bioreactors involve SBR-UAF-3SS. Each bioreactor was experimentally tested, demonstrating satisfactory performance in Chemical Oxygen Demand (COD) removal from industrial wastewater containing inhibitory substances (46-98%). In-situ remediation proposal will be tested in pilot scale in the subsoil within fuel service station in order to compare the kinetic coefficients of indigenous microbial performance with ex situ bioremediation treatment, by implementing air sparging system in the saturated zone and soil vapor extraction system in the unsaturated zone. Both systems will be installed in two soil cross sections comprising fifteen monitoring wells where the highest Benzene, Toluene, Ethylbenzene and Xylenes (mixed) and Total Petroleum Hydrocarbons concentrations were determined in strata comprising the interface between the saturated and unsaturated zones at depths between 3 and 8 m below ground surface.

DOI: https://doi.org/10.3850/978-90-833476-1-5_iahr40wc-p1114-cd

Year: 2023