Experimental design of wastewater treatment with electro-coagulation

摘要

Purpose - The purpose of this paper is to investigate the batch treatment of pulp and paper mill wastewater using electro-coagulation (EC). Design/methodology/approach - Statistical experimental design was used to investigate the effect of initial pH, current density and temperature. Experiments were planned to obtain the maximum amount of information in the fewest number of runs. Minimum-maximum values of current density, initial pH, temperature of medium were selected as 9-25 mA/cm~2, 5-9, 25-501C, respectively. A total number of 20 experiments including eight factorial points, six axial points and six replicates in centre points were carried out and experimental data were collected. Optimum operating parameters were determined by evaluating experimental results in MATLAB 7.9s. Findings - According to the results, the optimum values of current density, initial pH and temperature of medium are determined as 14.12 mA/cm~2, 8.22 and 34.211C, respectively. Practical implications - Many researches about different techniques including physical, chemical and biological methods have been done on the subject of pulp and paper wastewater treatment. In physical and chemical processes low molecular weight compounds are not removed efficiently, also these methods are quite expensive. Electrochemical degradation has an advantage of removing even the smallest colloidal particles compared with traditional flocculation and coagulation. Originality/value - Complete removal of pollutants, less sludge generation, simple process design and easy operation are standard features of the EC and it comes forward as one of the promising techniques.