Study And Performance Evaluation On Well Killing Fluid For Leak Resistance

Horizontal well will often encounter well killing in workover process,however well killing fluid leakage easily cause reservoir damage.Therefore,the well killing in the process of horizontal wells,especially in the face of special working conditions,should be capable of no pollution,low friction,easy flowback,stable performance.Workover well killing fluid of Huanxiling oilfield is mainly for sewage from combined station.Sewage into the formation leads to formation plugging,reservoir damage and production decrease after workover,which causes a great loss to oilfield.Therefore,the study on well killing fluid for leak resistance in the block of horizontal well is very necessary.This paper makes research on the Huanxiling oilfield horizontal well block,does harm analysis of the Union Station sewage,including chemical composition compatibility damage and insoluble particles damage,draws the conclusion of insoluble particles in the sewage damaging the reservoir.According to the damage mechanism of sewage components,on the basis of experiment,this paper carries out the study on well killing fluid additive.Aiming at the present situation of Huanxiling oilfield horizontal wells,this paper designs four sets of treatment scheme,makes performance evaluation of well killing fluid for leak resistance,and optimizes the schemes according to the actual site.The schemes using the oil-soluble particles to plugging reservoir and the Jia Min effect of the bubble to increase filtration resistance,reduces sewage leakage and the damage of sewage particles.Finally,through the construction site in two horizontal wells,the resumption of production after well killing achieves the desired objectives,which verify that the schemes in this paper have the value of popularization.