Enhanced bioelectrochemical treatment of petroleum refinery wastewater with Labaneh whey as co-substrate

Abstract

Petroleum refinery wastewater (PRW) that contains recalcitrant components as the major portion of constituents is difficult to treat by conventional biological processes. Microbial fuel cells (MFCs) which also produce renewable energy were found to be promising for the treatment of PRW. However, due to the high total dissolved solids and low organic matter content, the efficiency of the process is limited. Labaneh whey (LW) wastewater, having higher biodegradability and high organic matter was evaluated as co-substrate along with PRW in standard dual chambered MFC to achieve improved power generation and treatment efficiency. Among several concentrations of LW as co-substrate in the range of 5–30% (v/v) with PRW, 85:15 (PRW:LW) showed to have the highest power generation (power density (PD), 832 mW/m2), which is two times higher than the control with PRW as sole substrate (PD, 420 mW/m2). On the contrary, a maximum substrate degradation rate of 0.420 kg COD/m3-day (ξCOD, 63.10%), was registered with 80:20 feed. Higher LW ratios in PRW lead to the production of VFA which in turn gradually decreased the anolyte pH to below 4.5 (70:30 feed). This resulted in a drop in the performance of MFC with respect to power generation (274 mW/m2, 70:30 feed) and substrate degradation (ξCOD, 17.84%).

Iron Oxide–Modified Carbon Electrode and Sulfate-Reducing Bacteria for Simultaneous Enhanced Electricity Generation and Tannery Wastewater Treatment

“…Nevertheless, COD removal was further enhanced with the SRB-enriched Fe 3 O 4 @CF electrode where 75 ± 2.1% COD removal was accomplished ( Figure 3A ). The accelerated biodegradation of tannery wastewater in the MFCs with SRB enriched-Fe 3 O 4 @CF can be attributed to the anode electrode which provides a pathway for electron transfer to the cathode via an external circuit that can eventually boost the metabolic rate of microbes in the presence of these non-exhaustible electron acceptors ( Mohanakrishna et al, 2020 ; Hu et al, 2018 ). Furthermore, the improvement in tannery wastewater biodegradation rates attributed to SRB cultures suggests the enrichment of microbes which were highly specific to the biodegradation of recalcitrant pollutants in tannery wastewater.…”

Adsorptive potential of ZnO/SiO2 nanorods prepared via the sol–gel method for the removal of Pb(II) and Cd(II) from petroleum refinery wastewater

“…A 75 μm mesh sieve was used to sieve the crushed kaolin. To make a slurry, a known quantity (400 g) of crushed kaolin was soaked in 1000 cm 3 of distilled water for a week. The supernatant was decanted until the distilled water became colorless and the slurry was dried (overnight) at 100 °C.…”

“…1 The direct discharge of untreated petroleum wastewater has contaminated surface and groundwater resources with petrochemical products and consequently poses a significant risk to human health as well as animal life. 2,3 It has been reported that ca 3500-5000 L of petroleum wastewater are generated per tonne of crude oil processed. The wastewater generated from petrochemical industries contains several heavy metals such as vanadium, copper, cadmium, selenium, chromium, iron, lead and nickel, among others.…”

“…The growing human global population and demand–supply chain for petroleum products coupled with the expansion of petrochemical industries have led to the increasing release of refinery wastewater into the environment 1 . The direct discharge of untreated petroleum wastewater has contaminated surface and groundwater resources with petrochemical products and consequently poses a significant risk to human health as well as animal life 2,3 . It has been reported that ca 3500–5000 L of petroleum wastewater are generated per tonne of crude oil processed.…”

Contaminants Removal from Real Refinery Wastewater Associated with Energy Generation in Microbial Fuel Cell

“…The maximum efficiency (89%) detected at the applied voltage of 500 mV was nearly 50% higher than that of the control system (59%), which implied the effectiveness of auxiliary voltage in the treatment of PRW. Mohanakrishna et al (2020) added labneh whey as a co-substrate to improve the bio-electrochemical treatment of PRW in a dual-chamber MFC. The results showed a moderate removal efficiency (63.1%) for COD.…”