ORGANIC-REDUCTION OF TAPIOCA WASTEWATERS USING MODIFIED RBC

A modified Rotating Biological Contactor (RBC) was used for the treata bility studies of synthetic tapioca wastewaters. The RBC used was a fo ur stage laboratory model and the discs were modified by attaching por ous nechlon sheets to enhance biofilm area. Synthetic tapioca wastewat ers were prepared with influent concentrations from 927 to 3600 mg/l o f GOD. Three hydraulic loads were used in the range of 0.03 to 0.09 m( 3) . m(-2) . d(-1) and the organic loads used were in the range of 28 to 306 g COD . m(-2) d(-1). The percentage COD removal were in the ran ge from 97.4 to 68. RBC was operated at a rotating speed of 18 rpm whi ch was found to be the optimal rotating speed. Biokinetic coefficients based on Kornegay and Hudson models were obtained using linear analys is. Also, a mathematical model was proposed using regression analysis.