Pollution Research Paper

AEROBIC TREATMENT OF PHARMA WASTE WATER USING LAB SCALE ROTATING BIOLOGICAL CONTACTOR – A CASE STUDY

P.B. VYAS, M.P. TAMBE AND J.N. KHATRI

Abstract

Biological treatment using three-stage lab scale rotating biological contactor (RBC) was implemented for pharma waste containing high levels of COD & BOD. The RBC consists of 18 parallel discs rotating in a reservoir arranged in three stages. Six discs oriented in each stage, the reactor performance at different organic loading rates (2000, 3000, 4500, 7000 mg/L) at different RPM (5, 10, 15) was evaluated. The effect of hydraulic retention time disc submergence, and disc rotational speed on COD removal was examined. From the present study the optimum COD load was 4500 mg/L with removal efficiency of 95% at 5 RPM. COD removal efficiency increased 98% while HRT increased from 1 to 2.5 days. The COD removal efficiency increased from 70% to 93% as the disc submergence was increased from 36% to 40%. At submergence level of 20% the removal efficiency was increased due to activation of second and third compartments, when the rotational speed was increased from 5 to 15 RPM, the COD removal efficiency was decreased from 95% to 70% respectively. The stage COD removal efficiency was gradually decreasing with increasing number of stages and 80% of organic compounds were removed in the first stage of aerobic RBC.