Enhancement of PAHs degradation capacity through aerobic composting with the incorporation of bacillus subtilis

Abstract

   The swift progression of industrial growth and urban expansion has led to a heightened prevalence of diverse pollutants within our surroundings, notably polycyclic aromatic hydrocarbons (PAHs). Owing to their intrinsic properties, PAHs prove to be remarkably persistent contaminants with considerable biotoxic effects, prompting a worldwide effort to mitigate PAH pollution. This research aimed to explore the feasibility of curtailing PAH contamination from the sludge associated with the canals of Ho Chi Minh city via an aerobic incubation approach augmented with Bacillus subtilis (initial concentration of 106 CFU/ml) at a laboratory scale, utilizing a C:N ratio of 20:1, with adjustments made using ginger grass and boiler rice husk, alongside comprehensive data collection and analytical techniques. Findings indicated that temperatures peaked (50–65°C), the pH level steadily declined over time, moisture content soared (>60%) during the first ten days, and organic matter (OM) experienced a significant reduction from day 0 to day 36 (averaging from 64% to 35%). The treatment efficacy for PAHs via the aerobic incubation method ranged from a low of 29.2% to a high of 64.8%, with the control sample achieving merely 16.2% effectiveness.