Biofiltration of Mixed Hydrophilic and Hydrophobic Volatile Organic Compound Emissions from Wastewater Plants

Abstract

Volatile organic compound emissions from wastewater treatment plants contribute significantly to atmospheric pollution, odor generation, and occupational health concerns, particularly when both hydrophilic and hydrophobic compounds are present in mixed gaseous streams. The present study investigates the performance of biofiltration systems for the treatment of mixed hydrophilic and hydrophobic volatile organic compound emissions under controlled operating conditions. The research focuses on evaluating pollutant removal efficiency, microbial degradation activity, biofilter stability, and operational optimization associated with biological air treatment systems. Experimental analysis was conducted to examine the influence of gas residence time, moisture content, inlet pollutant concentration, packing material characteristics, nutrient availability, and airflow rate on biofiltration performance and contaminant biodegradation behavior. Results demonstrate that biofiltration effectively removes mixed volatile organic compounds through combined adsorption and microbial oxidation mechanisms, resulting in substantial reductions in gaseous pollutant concentrations and odor intensity. The study further reveals that optimized moisture conditions and nutrient supplementation significantly enhance microbial activity and improve degradation efficiency for both hydrophilic and hydrophobic compounds. Hydrophobic volatile organic compounds exhibited slower biodegradation rates due to limited mass transfer and lower bioavailability; however, appropriate packing media and acclimated microbial communities improved treatment performance. Comparative assessment with conventional physicochemical emission control technologies confirms the advantages of biofiltration, including lower energy requirements, reduced secondary pollution, and environmentally sustainable operation. In addition, the system demonstrated stable long-term treatment capability under variable emission loading conditions commonly encountered in wastewater treatment facilities.