Wastewater treatment from shale gas operation by Fenton process: a statistical optimization

Abstract

In this study, the removal of chemical oxygen demand (COD), color and total phenol in the generated shale gas wastewater by Fenton process was investigated. As known, during shale rock extraction, a large volume of water is used. The fracturing fluid has different toxic chemicals and additives, and therefore, shale gas extraction may lead to adverse environmental impacts including deterioration of soil, water and air quality. The main purpose of this study was to investigate the mitigation of the adverse effects of wastewater produced during shale gas extraction. For this purpose, the central composite design and the response surface methodology were used to design and optimize the performance of the Fenton process parameters. Experimental data was analyzed by the analysis of variance identifying the mechanism of interaction between the process variables and the dependent variables. Laboratory studies and the results of optimized parameters denoted that the model prediction data overlap with the experimental study data, quite successfully. At the end of the study, high removal efficiencies were achieved under the optimum conditions for COD (68.20%), color (88.48%) and total phenol (92.65%) removal, by means of the Fenton processes.