title: Treatment of hydraulic fracturing wastewater by wet air oxidation.
abstract: Wastewater produced by hydraulic fracturing for oil and gas production is characterized by high salinity and high chemical oxygen demand (COD). We applied a combination of flocculation and wet air oxidation technology to optimize the reduction of COD in the treatment of hydraulic fracturing wastewater. The experiments used different values of flocculant, coagulant, and oxidizing agent added to the wastewater, as well as different reaction times and treatment temperatures. The use of flocculants for the pretreatment of fracturing wastewater was shown to improve treatment efficiency. The addition of 500 mg/L of polyaluminum chloride (PAC) and 20 mg/L of anionic polyacrylamide (APAM) during pretreatment resulted in a COD removal ratio of 8.2% and reduced the suspended solid concentration of fracturing wastewater to 150 mg/L. For a solution of pretreated fracturing wastewater with 12 mL of added H2O2, the COD was reduced to 104 mg/L when reacted at 300 °C for 75 min, and reduced to 127 mg/L when reacted at the same temperature for 45 min while using a 1 L autoclave. An optimal combination of these parameters produced treated wastewater that met the GB 8978-1996 'Integrated Wastewater Discharge Standard' level I emission standard.
authors.affiliation: College of Geosciences, China University of Petroleum, Beijing 102249, China; State Key Laboratory of Petroleum Resource and Prospecting, China University of Petroleum, Beijing 102249, China; Beijing Key Laboratory of Oil and Gas Pollution Control, China University of Petroleum, Beijing 102249, China E-mail: yanxiuyi@cup.edu.cn.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.affiliation: College of Geosciences, China University of Petroleum, Beijing 102249, China; State Key Laboratory of Petroleum Resource and Prospecting, China University of Petroleum, Beijing 102249, China; Beijing Key Laboratory of Oil and Gas Pollution Control, China University of Petroleum, Beijing 102249, China E-mail: yanxiuyi@cup.edu.cn.
authors.forename: Xiuyi
authors.initials: X
authors.lastname: Yan
authors.affiliation: College of Geosciences, China University of Petroleum, Beijing 102249, China; State Key Laboratory of Petroleum Resource and Prospecting, China University of Petroleum, Beijing 102249, China; Beijing Key Laboratory of Oil and Gas Pollution Control, China University of Petroleum, Beijing 102249, China E-mail: yanxiuyi@cup.edu.cn.
authors.forename: Jinghui
authors.initials: J
authors.lastname: Zhou
authors.affiliation: College of Geosciences, China University of Petroleum, Beijing 102249, China; State Key Laboratory of Petroleum Resource and Prospecting, China University of Petroleum, Beijing 102249, China; Beijing Key Laboratory of Oil and Gas Pollution Control, China University of Petroleum, Beijing 102249, China E-mail: yanxiuyi@cup.edu.cn.
authors.forename: Jiuli
authors.initials: J
authors.lastname: Ma
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D000536:Aluminum Hydroxide / Q000737:chemistry; D057919:Biological Oxygen Demand Analysis; D005427:Flocculation; D006861:Hydrogen Peroxide / Q000737:chemistry; D016877:Oxidants / Q000737:chemistry; D010084:Oxidation-Reduction; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000737:chemistry*; D000099166:Polyacrylamides
chemical_list: D000180:Acrylic Resins; D000536:Aluminum Hydroxide; D006861:Hydrogen Peroxide; D016877:Oxidants; D062065:Wastewater; D000099166:Polyacrylamides; C016213:aluminum oxychloride