Research and application of nitrogen foam displacement system in Henan heavy oil water flooding reservoir

Henan heavy oil water-flooding reservoir has characteristics of "shallow,thin and heavy",with good reservoir connectivity and strong heterogeneity.After more than 20 years of water flooding development,water cut rose fast,and the nitrogen foam flooding technology research has been carried out.Through formulation experiment and physical model experiment,foam flooding system suitable for Henan heavy oil water flooding reservoir has been developed.Through 10 times and 20 times differential core displacement experiment under co-injection and separated layer production,the recovery degree increased by 30.2% and 24.7%,which confirms the compound foam displacement system has good profile control and oil displacement effect.After the field application of nitrogen foam displacement system in 3wells of Gucheng and Wangji oilfields,obvious effect of increased oil production and reduced water cut have been achieved.