Treatment of Pulp and Paper Wastewater by Electro Fenton Process

Abstract

The wastewater generated from pulp and paper industry has widespread environmental impact on land mass and aquatic life. The wastewater generated by these industries contains high COD, BOD, colour, organic substances and toxic chemicals. Lignin is the main constituent responsible for colour in the pulp and paper industry. The conventional treatment technologies have not been very effective for the treatment of pulp and paper industry wastewater. Electro Fenton process is a technology leading to the total elimination of toxic, organic and inorganic substances present in the wastewater. In this study, the feasibility of degradation of black liquor and secondary treated pulp and paper industry wastewater was investigated by Electro Fenton process. The wastewater was characterized and the degradation was monitored by means of colour and COD. The effect of operational variables such as pH, concentration of H2O2, dosage of Fe2+, contact time and current efficiency were studied for arriving at optimum operating variables. A kinetic study of Electro Fenton process was conducted with optimum operating variables and the degradation was found to follow the pseudo-first order kinetic model and the kinetic rate constant (k) was found out. The rate of degradation efficiency of wastewater was found to be higher using Electro Fenton process than the other advanced treatment technologies. Hence, this Electro Fenton process can be considered as a suitable alternate treatment method for pulp and paper wastewater containing for non-biodegradable pollutants.