苏北盆地ZC油田废弃钻井液再利用调剖工艺

苏北盆地ZC油田高含水开发后期储层内部出现不同级次的窜流通道，注入水沿窜流通道无效、低效循环，导致水油比急剧上升、采油成本大幅攀升、经济效益显著降低，为解决该问题，研究了废弃钻井液再利用调剖工艺。根据调剖堵水工艺原理，通过室内试验进行了废弃钻井液再利用调剖体系的可行性研究，采用搅拌及调节pH值的方式提高调剖体系的封堵效果，最终形成了废弃钻井液再利用调剖工艺。现场试验证明，该工艺具有较好的堵水、改善吸水剖面的效果，可以达到了废弃钻井液再利用，避免污染，降低调剖成本的目的。研究结果表明，废弃钻井液再利用调剖工艺可为高含水油田低成本调剖提供技术支撑。 

Profile Control for Wasted Drilling Fluid Recycling in ZC Oilfield of the Subei Basin

Due to emerging channeling-paths inside the reservoir and ineffective and inefficient circulation of injected water along the paths in the late high water cut development stage of ZC Oilfield,the water-to-oil ratio may rise sharply,resulting in a rapid increase in development costs and an obvious decline in economic benefits.Incorporating the principles of profile control and water plugging,a feasibility study on the profile control system of wasted drilling fluid recycling was conducted through lab tests,in which the sealing effect of this system was changed by stirring and pH value adjustment.Finally,the profile control system of wasted drilling fluid recycling was determined.Field tests showed that this process achieves a good performance in water plugging and water absorption structure modification,and also accomplishes wasted drilling fluid recycling.The system could prevent pollution from wasted drilling fluid and reduce profile control costs.This technology would provide technical support for the low-cost profile control of high water cut oilfields.