Evaluation of harmful gases and odors reduction and industrial accident prevention in septic tanks using a microbial consortium

Abstract This study aimed to mitigate the harmful gases and odors produced in anaerobic wastewater treatment settings, such as septic tanks, and assess their potential to prevent industrial incidents, including fires, explosions, and suffocation. To achieve this, sludge samples collected from the anaerobic tank of a septic tank were treated with different concentrations (0, 0.5, 1.0, 1.5, 2.0, and 2.5%) of a mixed microbial formulation, and changes in pH, hydrogen sulfide, ammonia, volatile organic compounds, and complex odors were monitored for 48 h. In the groups treated with the mixed microbial formulation, the pH initially decreased and then stabilized, with the 1.0–1.5% treatment groups exhibiting the most stable fermentation and metabolic balance. Hydrogen sulfide levels fell below the detection limit or decreased by over 99% within 48 h in the 0.5–1.5% treatment groups, and ammonia levels decreased by more than 99%. Volatile organic compounds declined rapidly at higher treatment concentrations, reaching detection limits within 24 h in the groups treated with 2.0% or higher. Complex odors were reduced by approximately 98%, indicating a substantial decrease across various odor components.