裂缝性低渗油藏周期注水与渗吸效应实验

结合长岩心周期注水实验与不同压降条件下的渗吸实验,得出了渗吸效应在周期注水中所起的作用,进行了不同周期下的周期注水实验、无压降条件下的静态渗吸实验、不同压力及压降幅度下的动态渗吸实验,并将三者进行了对比.研究结果表明,周期注水在裂缝性低渗透油藏的开采中效果明显;低渗透基质油藏中毛管力具有较强作用;压力波动幅度对渗吸效应的影响呈先减小后增大的趋势,综合低渗透油藏中较强的压敏性,得出周期间歇性注水实验过程中,压力波动幅度较低才能获得较高采收率.

Cyclic waterflooding and imbibition experiments for fractured low-permeability reservoirs

The effect of imbibition on the cyclic waterflooding of the fractured low-permeability reservoirs is obtained according to the cyclic waterflooding experiment of long cores under different cycles,their static imbibition experiments without pressure drop and their dynamic imbibition experiments at different pressure drop.The results show that cyclic waterflooding has obvious effect on the recovery of the fractured low-permeability reservoirs;there is a strong capillary effect is in the low permeability matrixes;the effect of pressure fluctuation amplitude on the imbibition presents the trend of first decreasing and then increasing;pressure fluctuation amplitude must be in lower level in order to obtain higher recovery factor due to the strong pressure sensitivity of the low permeability reservoirs.