Optimal Study For Alkalescence ASP Flooding In Formation Type ? East Block Of Nan 4

Block Nan 4 of Saertu oilfield is located in the south of Daqing,with a area of 8.90km2,and the geological reserves is 4839.36×104t.The line pattern was put into development in the year of 1956,the well spacing is(3-(800,500)×450(500,(250,300))).The first infill well pattern was taken out in 1984,the second infill well pattern was taken out in 1996,the third infill well pattern was taken out in 2001.The polymer flooding test of formation type III was taken out between N4-10~N4-3 in east of block Nan 4.The paper aims at the alkalescence ASP flooding of formation type II in east of block Nan 4,an optimal schme is designed.Frist,the paper gives an optimal design on the oil flooding system,combined with the development experience of pilot test,the development effect of both ASP and alkalescence ASP flooding are analyzed.Both increase the degree of recovery,while the injectability of alkalescence ASP flooding is better than ASP.At the same time produced fluid treatment difficulty of alkalescence ASP is lower than the ASP system.In the light of the formation features of Nan 4,the optimal injection system is alkalescence ASP flooding system.The well spacing,injection rate,slug combination parameters are optimized.At last,according to the injection parameter optimization design,the development effect of formation type II for alkalescence ASP flooding is predicted.The water cut reached 98%,when the cumulative injection pore volume is 1.304 PV.The recovery degree is 67.44%,stage recovery degree is 20.61%,the alkalescence ASP improve the recovery efficiency of 16.35%.The stage cumulative oil production is 138.84×104t,the recoverable reserves by alkalescence ASP increase by 62.68×104t.