Sustainable Management of Oily Petroleum Refinery Sludge Through Anaerobic Digestion with Bioenergy Production

The increased demand for energy has resulted in a notable expansion of petroleum refineries, leading to a significant rise in the production of oily petroleum refinery sludge. This sludge is primarily characterized by complex hydrocarbons, persistent organic compounds, and a combination of hazardous substances such as cyanides, sulfides, and ammonia. Given its heterogeneous composition, it is imperative to treat petroleum refinery sludge before disposal. Although energy-intensive combustion methods like incineration, pyrolysis, and landfilling are available, they are not sufficient to handle the large quantities of waste being generated. Ultrasonic treatment and solvent extraction also fall short of effectively managing this waste. An effective, cost-efficient, and sustainable approach for treating petroleum refinery waste, particularly secondary biological waste, is anaerobic digestion (AD). However, numerous challenges hinder the AD process for toxic and oily petroleum refinery sludge. This chapter explores various strategies employed in the AD of petroleum refinery sludge such as co-digestion, bioaugmentation, and others, and evaluates their suitability under different conditions. Additionally, the study emphasizes the complete mitigation of petroleum refinery sludge, with a particular focus on the recovery of biogas.