Isotherm Studies on Dairy Industry Wastewater Using Neem Leaves Powder

The effectiveness of neem leaves powder, a cheap agro-based product, as a coagulant was evaluated to remove COD and TDS present in a dairy industry wastewater. Experiments were carried out by adding neem leaves powder to the dairy industry wastewater at different dosages, different rapid mixing contact time and slow mixing contact time. Maximum removal of COD and TDS in a dairy industry effluent was obtained at an optimum dosage of 50 mg/l, an optimum rapid mixing contact time of 8 min. and an optimum slow mixing contact time of 20 min. The experimental data were analyzed using the Langmuir and Freundlich isotherm models. Based on regression coefficient, the equilibrium data found fitted well with the Langmuir isotherm model than that of Freundlich isotherm model. The results indicated that the use of neem leaves powder to remove COD and TDS present in a dairy industry wastewater seems to be an economical and worthwhile alternative over conventional methods.