Research On Steam Flooding Test After Polymer Flooding In Beierxi Zone Of Sabei Oilfield

By the end of December 2008,there has been 16 polymer flooding blocks which has entered into subsequent water flooding stage in daqing oilfield,geological reserve is 2.75 x 108 t,and recovery degree is 52.5 percent,after polymer flooding,there is still nearly half of the geological reserves remained in reservoir.Indoor research and coring well data show that those remained reserves are mainly concentrated on the top of the thick reservoir,and it has become a Problem that urgently need to be solved about How to further improve the recovery degree of remaining oil.During the steam flooding developing process,Under the premise of the Profile control by heat resisting foam,take advantage of the property of over laying by steam in the well hole and reservoir,reduce the bad influence on injecting steam,which comes from big hole and secondary water that was produced in Reservoir bottom during the water flooding and polymer flooding process,give full play to the role of steam to distillate oil and reducing the viscosity,so as to improve the Liquidity and crude oil quality near the producing well,and producing much more remaining oil which distributing in the top of the thick reservoir and thin differential layer,further improve the oil recovery of the reservoir after water and polymer flooding.Steam flooding test which were carried out after water flooding in Putaohua oilfield Pu71-75 well group,cumulatively increase the pro-ductility of crude oil 4176 tons in one year,good results were obtained.The test which were carried out after ASP flooding in closely-spaced well test region in Sa?12 reservoir,the central well block get the same effect of improve the productivity of oil as ASP flooding.Both tests show that the development way of hermit recovery by steam flooding after water and ASP flooding can further achieve a certain effect in multiple sandstone zone reservoirs with thin oil.But as a result of the test scale is small,the testing results of evaluation has limitations,too.The result shows the technology and economic feasibility of carrying out steam flooding after water and polymer flooding in reservoir.Determine the reasonable injection and production parameters in major reservoir,erfect the related technology and provide technical support for the secondary development of the reservoir after water and polymer flooding.