Study of enhanced oil recovery lab in low permeable and heterogeneity reservoir

When development by water flooding is applied in low permeable and heterogeneous reservoir,injected water is easy to cause channeling along high permeable parts,but produced degree for low permeable reservoir is poor and the development effect is also poor.Thus,the method to further improve development effect after water flooding and produced degree of low permeable reservoir is significant.In this paper,the functions of several methods including intermittent production,nitrogen gas injection and water alternating gas injection are investigated after conventioal water flooding in low permeable and heterogeneity reservoir,and also feasible methods of enhance oil recovery is further discussed.The lab results demonstrate that,applied reasonable method can further enhance oil recovery based on water flooding,of which,recovery factor of intermittent exploitation is up to close 7% but effective cycle is short,the recovery factor by nitrogen gas injection is up to 6% but easily leading to invalid cycle after gas breakthrough generated,howerer,water alternating gas injection is best which can enhance oil recovery of 15%.