Bagasse wastewater treatment using biopolymer: A novel approach

Abstract

In this present study, the removal of turbidity, biological oxygen demand (BOD) and chemical oxygen demand (COD) were investigated under different operating conditions such as agitation time (X1: 15-25 min), initial pH (X2:4-8), chitosan dose (X3:1.2-2 g L-1) and settling time (X4:40-80 min) to treat bagasse based paper and pulp industry wastewater via response surface methodology (RSM). The experimental data obtained were fitted to a second-order polynomial equation using multiple regression analysis and ANOVA (analysis of variance) was used to examine the significance of the developed mathematical models. The 3-D response surface plots were derived from the mathematical models in order to study the interactive effects process variables on the treatment efficiency. Derringer?s desired function methodology were applied to determine the optimal conditions and it was found to be: agitation time of 20 min, initial pH of 6, chitosan dose of 1.8 gL-1 and settling time of 60 min. Under these conditions, the removal of turbidity, BOD and COD were found to be 84 %, 90 % and 93 % respectively.