Treatment of oil sands produced water using combined electrocoagulation and chemical coagulation techniques

Laleh Shamaei; Behnam Khorshidi; Basil Perdicakis; Mohtada Sadrzadeh

doi:10.1016/j.scitotenv.2018.06.387

Treatment of oil sands produced water using combined electrocoagulation and chemical coagulation techniques

Sci Total Environ. 2018 Dec 15:645:560-572. doi: 10.1016/j.scitotenv.2018.06.387. Epub 2018 Jul 18.

Authors

Laleh Shamaei¹, Behnam Khorshidi², Basil Perdicakis³, Mohtada Sadrzadeh⁴

Affiliations

¹ Department of Mechanical Engineering, 10-367 Donadeo Innovation Center for Engineering, Advanced Water Research Lab (AWRL), University of Alberta, Edmonton T6G 1H9, AB, Canada. Electronic address: shamaeig@ualberta.ca.
² Department of Mechanical Engineering, 10-367 Donadeo Innovation Center for Engineering, Advanced Water Research Lab (AWRL), University of Alberta, Edmonton T6G 1H9, AB, Canada. Electronic address: behnam@ualberta.ca.
³ Suncor Energy Inc., P.O. Box 2844, 150-6th Ave. SW, Calgary T2P 3E3, Alberta, Canada. Electronic address: bperdicakis@suncor.com.
⁴ Department of Mechanical Engineering, 10-367 Donadeo Innovation Center for Engineering, Advanced Water Research Lab (AWRL), University of Alberta, Edmonton T6G 1H9, AB, Canada. Electronic address: sadrzade@ualberta.ca.

PMID: 30029132
DOI: 10.1016/j.scitotenv.2018.06.387

Abstract

Hybrid electrocoagulation-chemical coagulation (EC-CC) process has attracted a growing attention for the removal of various types of wastewaters contaminants. In this paper, the feasibility of EC-CC technique as an alternative to conventional chemical processes for the treatment of steam assisted gravity drainage (SAGD) produced water has been systematically studied. Eight parameters, namely electrode material, cell configuration, pH and temperature of the solution, chemical coagulant dosage, intensity of the electrical current, mixing rate, and treatment time were studied. To explore the synergistic effect of the design parameters, the experimental trials were arranged using Taguchi method. Analysis of variance (ANOVA) was performed to evaluate the effect of each design parameter on the organic matter removal from the SAGD produced water. It was found that all parameters except the electrode arrangement had a significant effect on the removal efficiency of the EC-CC process. Among these parameters, the chemical coagulant and the treatment time had the most significant contribution to the efficiency by 40% and 26%, respectively. The optimum condition for the highest TOC removal efficiency (39.8%) was obtained by applying 0.34 A to Al electrode in a bipolar (BP) configuration when the pH, temperature, coagulant concentration, mixing rate, and reaction time were set to 8, 60 °C, 200 mg/L, 700 rpm, and 90 min, respectively. Moreover, a second-order polynomial regression model was proposed to predict the removal efficiency in terms of design parameters. An excellent agreement between the model predictions and experimental data was obtained with the adjusted R² of about 99%.

Keywords: Design of experiment (DOE); Electrochemical coagulation; Electrocoagulation; Oil sands; SAGD produced water; Taguchi.