Application of an integrated system of coagulation and electrodialysis for treatment of wastewater produced by fracturing

摘要

In order to produce large quantities of newly discovered unconventional oil and gas, hydraulic fracturing of wells is commonly practiced in the oilfields. While the "Frac jobs" for shale gas are completed, tremendous water will flow back to the surface, and then fracturing wastewater is generated. In this study, an integrated process consisting of coagulation and electrodialysis (ED) is proposed to treat the fracturing wastewater. The coagulation is used to remove the organic contaminants and purify the water. The chemical oxygen demand and turbidity is recorded before and after experiment in order to monitor the coagulant effect. In the ED system, the ion-removal efficiency is studied to measure the desalinating effect. The removal rate of ions reach up to 91%, except that the removal rate of