A Sustainable Strategy for Petrochemical Wastewater Treatment via Anaerobic Co-Digestion

Abstract

AbstractPetrochemical manufacturing processes release large amounts of water composed of organic and inorganic compounds, imposing high pollution loads on the receiving environment. Treating this petrochemical wastewater (PCW) using a biological system is essential to protecting the environment and human health, with a dual benefit of bioenergy production. In this study, PCW was mixed with domestic wastewater (DWW) at different PCW: DWW v/v ratios of 0:1, 1:2, 1:1, 2:1, and 1:0, and subjected to anaerobic digestion for eliminating chemical oxygen demand (COD) and recovering methane-rich biogas (CH4). The highest bio-CH4 yield of 281.55 mL/gCODremoved, with COD reduction = 93.8%, was observed at 1:1 (PCW: DWW) under mesophilic conditions for 192 h. Increasing the PCW fraction was associated with the deterioration of the biological activity, where bio-CH4 yield dropped to 196.02 mL/gCODremoved at PCW: DWW of 2:1. The study demonstrated that adding DWW to the industrial effluent could be a reliable strategy for diluting the organic load, thus avoiding methanogenesis inhibition from volatile fatty acids (VFAs) accumulation. Accordingly, the study outputs (dual wastewater treatment and biogas recovery) would meet the 2030 Agenda for sustainable development related to water resource management and renewable energy generation.KeywordsCo-substrateTerephthalic acid wastewaterDomestic sewageMethane-rich biogasSustainable Development Goals (SDGs)