Biodegradation of Phenol using Rotating Biological Contactor

Many industries generate phenolic pollutants during their manufacturing processes. Due to its toxic nature, it poses severe threat to environment if disposed untreated. In the present study the removal efficiency of phenol in a batch flow, single-stage lab-scale rotating biological contactor (RBC) is investigated. The ambient room temperature during the study period was between 27–32°C. The impact of process variables, viz concentration of phenol, rotational speed and percentage submergence of discs on phenol removal from was examined. It was observed that the phenol removal was 99% at concentrations from 40 to 180 mg/L. Reactor performance deteriorated when pheno1 concentration increased to 200 mg/L. Hydraulic retention time (HRT) required to achieve 99% phenol removal at the optimal phenol concentration of 180 mg/L was reduced with the increase in rotational speed (50, 75 and 100 rpm; HRT of 36, 28 and 24 hours respectively). The dissolved oxygen increased with the increase in rotational speed. At different percentage submergence of discs i.e., 40%, 35% and 30% to achieve 99% removal, the HRT's were i.e., 24, 28 and 32 hours respectively. As the submergence of discs decreased the HRT increased.