气田压裂返排液回用影响因素研究

针对气田压裂返排液回用配制压裂液的水质要求,研究了pH值、金属离子、细菌和泡沫对处理后液体配制压裂液的影响。结果表明,通过调节pH值、控制金属离子浓度、加入杀菌剂和消泡剂可以达到回用配制压裂液的要求。其中,pH值应控制在6.5左右;当Na2CO3和NaOH的复配比为800/600、NaOH投加量为300mg/L时,能有效去除Ca2+、Mg2+、Fe3+等离子的影响;杀菌剂采用气田压裂专用杀菌剂;消泡剂采用二甲基硅油。实验在气井井场采用撬装微涡流混凝装置处理气田压裂返排液,并对上清液回用配液,回用率达到98.4%。

Study on Effects of Factors on the Fracturing Flowback Fluids Reuse in Gas Field

The impact factors such as pH,metal ion,bacteria and foam for the reuse of fracturing flowback fluids in gas field were analyzed.The results showed that:by adjusting pH,controlling metal ion concentration,adding bactericide and defoamer could meet the requirements of fracturing fluids reuse.When the Na2CO3 to NaOH ratio stayed around 800/600,with a NaOH dosage around 300 mg/L,the Ca2+、Mg2+、Fe3+ could be removed with a pH of 6.5.The bactericide and the simethicone specially designed for gas field was applied,as well.The above experimental treatment was used in a gas field a with skid-mounted micro-vortex coagulation device,and the reuse rate of fracturing flowback fluids reached 98.4%.