Studies on organic removal of 2,4-dichlorophenol wastewaters using a modified RBC

Abstract

Phenolic compound wastes from a large number of industries big and small which are highly toxic and pose a direct threat to human and aquatic life are generally let into the rivers and coastal waters. 2,4-dichlorophenol is used in the manufacture of industrial and agricultural products such as pesticides, germicides, soil sterilants, seed disinfectants and antiseptics. A modified Rotating Biological Contactor (RBC) was used for the treatability studies of synthetic 2,4-di-chlorophenolic (2,4 CP) wastewaters. The RBC used was a four stage laboratory model and the discs were modified by attaching porous netlon sheets to enhance biofilm area and volume. Synthetic wastewaters were prepared with influent concentrations from 40 to 200 mg/l of 2,4 CP. Four hydraulic loads were used in the range of 0.024 to 0.065 m3.m-2.d-1 and the organic loads used were in the range of 2 to 13 g 2,4 CP.m-2.d-1. The RBC was operated at a speed of 12 rpm. Effect of hydraulic loadings and influent 2,4-dichlorophenol concentration on 2,4-dichlorophenol removal were discussed and showed maximum organic removal at hydraulic loads of 0.024 and 0.046 m3.m-2.d-1. Also, a correlation plot between 2,4 CP applied and 2,4 CP removed was presented. A mathematical model was proposed using regression analysis.