微电解—Fenton氧化—絮凝组合工艺处理油田压裂废水

采用微电解—Fenton氧化—絮凝组合工艺处理油田压裂废水,优化了工艺条件。实验结果表明：最佳工艺条件为初始废水pH 3.0、铁屑加入量1.5 g/L（铁屑与活性炭的质量比1∶1）、微电解时间80 min、Fenton氧化时间120 min、H₂O₂加入量940 mg/L,阳离子聚丙烯酰胺加入量120 mg/L;在最佳工艺条件下处理废水后,COD由3 116.0 mg/L降至681.3 mg/L,总COD去除率达78.1%,3个工段的COD去除率依次为33.1%,37.9%,7.1%,出水水质满足现场回注标准（SY/T 5329—2012《碎屑岩油藏注水水质推荐指标及分析方法》）;该组合工艺对废水的处理效果远优于单独微电解、Fenton氧化或絮凝工艺,且方法简单易行、药剂利用率高。

Treatment of oilfield fracturing wastewater by combination process of micro-electrolysis-Fenton oxidation-flocculation

The oilfield fracturing wastewater was treated by combination process of micro-electrolysis-Fenton oxidation-flocculation,and the process conditions were optimized. The experimental results show that:Under the optimum process conditions of initial wastewater pH 3.0,iron filings dosage 1.5 g/L(the mass ratio of iron filings to activated carbon is 1∶1),micro-electrolysis time 80 min,Fenton oxidation time 120 min,H2O2 dosage 940 mg/L and cationic polyacrylamide dosage 120 mg/L,the wastewater COD is dropped from 3 116.0 mg/L to 681.3 mg/L with 78.1% of total COD removal rate and 33.1%,37.9%,7.1% of COD removal rate of the three processes respectively, and the effluent water quality meets the on-site injection standardof SY/T 5329-2012;The treatment effect of the combination process is much better than that of micro-electrolysis,Fenton oxidation or flocculation process,and the process is a simple method with high utilization rate of chemical reagents.