Sewage enhanced bioelectrochemical degradation of petroleum hydrocarbons in soil environment through bioelectro-stimulation

Gunda Mohanakrishna; Riyadh I Al-Raoush; Ibrahim M Abu-Reesh

doi:10.1016/j.btre.2020.e00478

Sewage enhanced bioelectrochemical degradation of petroleum hydrocarbons in soil environment through bioelectro-stimulation

Biotechnol Rep (Amst). 2020 May 26:27:e00478. doi: 10.1016/j.btre.2020.e00478. eCollection 2020 Sep.

Authors

Gunda Mohanakrishna¹, Riyadh I Al-Raoush¹, Ibrahim M Abu-Reesh²

Affiliations

¹ Department of Civil and Architectural Engineering, College of Engineering, Qatar University, P O Box 2713, Doha, Qatar.
² Department of Chemical Engineering, College of Engineering, Qatar University, P O Box 2713, Doha, Qatar.

Abstract

The impact of readily biodegradable substrates (sewage and acetate) in bioelectroremediation of hydrocarbons (PW) was evaluated in a bench-scale soil-based hybrid bioelectrochemical system. Addition of bioelectro-stimulants evidenced efficient degradation than control operation. Acetate and sewage were exhibited power density of 1126 mW/m² and 1145 mW/m², respectively, which is almost 15 % higher than control (without stimulant, 974 mW/m²). Increased electrochemical activity was correlated well with total petroleum hydrocarbons (TPH) degradation through addition of acetate (TPH_R, 525 mg/L, 67.4 %) and sewage (TPH_R, 560 mg/L,71.8 %) compared to the control operation (TPH_R, 503 mg/L, 64.5 %). Similarly, chemical oxygen demand (COD) reduction was also enhanced from 69.0 % (control) to 72.1 % and 74.6 % with acetate and sewage, respectively. Sewage and acetate also showed a positive role in sulfates removal, which enhanced from 56.0 % (control) to 62.9 % (acetate) and 72.6 % (sewage). This study signifies the superior function of sewage as biostimulant compared to acetate for the bioelectroremediation of hydrocarbons in contaminated soils.

Keywords: Applied potential; BES, Bioelectrochemical system; BET, Bioelectrochemical treatment; COD, Chemical oxygen demand; DROs, Diesel range organics; EAB, Electroactive anodic biofilms; In situ bioelectroremediation; MFC, Microbial fuel cell; PRW, Petroleum refinery wastewater; PW, Produced water; Petroleum hydrocarbons; Produced water; SRB, Sulfate reducing bacteria; Sewage supplementation; TDS, Total dissolved solids; TPH, Total petroleum hydrocarbons; TPHR, Total petroleum hydrocarbons removal.