新型三维电化学氧化体系处理压裂返排液

采用不锈钢作阴极、镀钌铱的钛板作阳极、铁碳材料作粒子电极,构建新型三维电化学氧化体系,处理压裂返排液,并通过响应曲面法考察COD去除率和除油率的影响因素。实验结果表明:回归方程的相关系数及校正相关系数均大于0.9,回归方程的线性关系显著;返排液COD去除率和除油率影响因素的大小顺序均为电流电解时间粒子填充比,其中关键因素是电流,电解时间和粒子填充比之间的交互作用具有较大影响;在电解时间为31.8 min、电流为4.4 A、粒子填充比为61.2%的条件下,COD从606.4 mg/L降至68.5 mg/L,含油量从153.7 mg/L降至9.1 mg/L,达到GB 8978—1996《污水综合排放标准》中的一级标准。

New three-dimensional electrochemical oxidation system for treatment of fracturing flow-back fluid

A novel three-dimensional electrochemical system was established using stainless steel as cathode,ruthenium-iridium-doped-titanium plate as anode and iron-carbon material as particle electrode,for treatment of fracturing flow-back fluid. The factors affecting COD removal rate and oil removal rate were investigated by response surface methodology. The experimental results showed that：The correlation coefficient and adjusted correlation coefficient of the regression equation were both greater than 0.9,which indicated the significant linear characteristics of the regression equations;The order of factors affecting COD removal rate and oil removal rate of the fracturing flow-back fluid were current>electrolysis time>particle filling ratio,and the key factor was current,while the effect of interaction between electrolysis time and particle filling ratio was great;Under the conditions of electrolysis time 31.8 min,current 4.4 A and particle filling ratio 61.2%,COD decreased from 606.4 mg/L to 68.5 mg/L,and the oil content decreased from 153.7 mg/L to 9.1 mg/L,which met the first class standard of the Integrated Wastewater Discharge Standard（GB 8978-1996）.