埕东油田强化泡沫驱矿场驱油效果

Pilot test of polymer enhanced foam flooding in Chengdong oilfield

通过对四类油藏典型代表埕东油田实施强化泡沫驱先导试验和矿场注入产出动态特征分析,描述了油藏条件下强化泡沫驱的封堵调剖性能和驱油效果.2004年矿场试验实施以来,注入井注入压力上升了5.2MPa,阻力因数增大到4.86,压力上升幅度和阻力因数远大于聚合物驱单元的;平面上驱替相推进速度明显低于水驱推进速度,纵向吸水剖面得到改善;3口中心井均见到明显降水增油效果;到2009年7月,累积增油16810t,其综合含水率下降趋势类似于聚合物驱在一、二类油藏的应用效果,说明强化泡沫体系能有效地封堵油藏大孔道,增大油层渗流阻力,扩大波及体积,从而提高四类油藏的原油采收率,是胜利油田强非均质性油藏和大孔道发育油藏提高采收率的有效方法.

The pilot test of polymer enhanced foam flooding was implemented in 2004 in Chengdong oilfield,representative of strong heterogeneity reservoirs and pore and void growing reservoirs.This paper describes and analyzes the performance of injecting and production wells and evaluates the flooding effects.The injection pressure went 5.2 MPa up and the flow resistance coefficient increased to 4.86,far greater than that of polymer flooding.The displacement velocity was lower than that of water flooding in plane and the profile modified evidently in vertical.The oil production increased and the water cut decreased in the three center wells.The incremental oil production was168 10 t by the end of July,2009.The decline trend of water cut is similar to that of polymer flooding in Gudao oilfield.Therefore the polymer enhanced foam system could plug up the pore and void effectively,increase the flow resistance greatly,extend the swept volume in plane,enhance the displacement efficiency in vertical,and then enhance the oil recovery in strong heterogeneity reservoirs and in pore and void growing reservoirs in Shengli oilfield.