Rotating Biological Contactor System Performance for Simultaneous Nitrification and Denitrification in Domestic Sewage
Keywords:
Rotating Biological Contactor, Simultaneous Nitrification–Denitrification, Domestic Sewage Treatment, Biological Nitrogen Removal, Biofilm Reactor, Wastewater Treatment TechnologyAbstract
Domestic sewage containing elevated nitrogen compounds contributes significantly to eutrophication and deterioration of aquatic ecosystems when discharged without adequate biological treatment. Efficient nitrogen removal technologies are therefore essential for sustainable wastewater management and environmental protection. The present study investigates the performance of a rotating biological contactor system for simultaneous nitrification and denitrification in domestic sewage treatment under controlled operational conditions. The research focuses on evaluating nitrogen conversion efficiency, biofilm development, organic matter removal, and operational stability associated with attached-growth biological treatment processes. Experimental analysis was conducted to examine the influence of rotational speed, hydraulic retention time, organic loading rate, dissolved oxygen concentration, and wastewater characteristics on nitrification–denitrification performance and microbial activity. Results demonstrate that the rotating biological contactor system effectively supports the growth of diverse microbial communities capable of simultaneous aerobic nitrification and anoxic denitrification within different biofilm layers, resulting in substantial nitrogen removal efficiency. The study further reveals that optimized rotational speed and hydraulic conditions significantly improve oxygen transfer, substrate diffusion, and microbial metabolism, thereby enhancing ammonia oxidation and nitrate reduction processes. Stable biofilm formation contributed to improved resilience against hydraulic and organic loading fluctuations commonly observed in domestic sewage treatment systems. Comparative assessment with conventional activated sludge systems confirms the advantages of rotating biological contactors, including lower energy consumption, reduced sludge production, and simplified operational requirements.
