Study On Foam Flooding Scheme Of Well No.21 In Xinjiang

It is necessary to select a representative area for chemical flooding pilot test in the reservoir area of Baikouquan Formation in Xinjiang bai21 well area.Because of the poor physical properties of the reservoir,the lower viscosity of crude oil,the uncertainty of polymer flooding,further technical screening is carried out in the aspects of polymer flooding,foam flooding and ASP flooding,and the optimal chemical flooding of Baikouquan reservoir is demonstrated.This paper is a pilot experiment of bubble flooding technology.The first part includes of apparent performance evaluation and optimization of foam which is formed by four kinds surfactants.Those surfactants,G2,FOR3,KPS and Twelve alkyl sodium sulfate,would be analyzed of their foam property and stability.Then,the effect of polymer on foaming ability and stability of foam was studied and then reasonable molecular weight and concentration of polymer were be find.The last,the oil displacement system for Xinjiang Bai 21 wells could be filtered out mainly through the indoor experiment.The performance of four kinds of foaming agent was studied,such as foaming ability,half life,liquid half life,surface tension and surface viscosity,and the surfactant G2 with the concentration of 0.5wt% has the best performance.After the studies,the polymer can enhance the stability of foam but also restrain its foaming capacity.When the polymer concentration is too high,the stability of the foam will be reduced.Indoor physical model experiment were carried on two parts.The first part is the system selection of enhanced foam,0.5wt%G2 with 15 million molecular weight polymer can get the best effect.The second part is about the PV of injected solution,while the injection solution volume is 0.7PV,the maximum recovery and optimal cost could be reached.