纵向渗透率级差对水驱油特征的影响实验研究

INFLUENCE OF LONGITUDINAL PERMEABILITY DIFFERENTIAL ON WATERFLOODING CHARACTERISTICS

为了研究不同渗透层位渗透率级差对各层驱油特征的影响,开展了不同渗透率级差的岩心并联驱替实验。结果表明,液流速度总是随着驱替压差的增大而增大的,高渗透岩心总是比低渗透岩心增加的更快些;岩心流速级差明显要大于渗透率级差;渗透率级差越大,流速级差和驱油效率级差越大;渗透率级差越大,低渗层启动压力越大,低渗层越难动用。在多油层共同进行开发时,应对高低渗透性层位进行合理的划分,尽量避免将渗透率级差过大的层系划分为统一开发层系进行开采。

To study the relation between permeability differential and flooding characteristics,parallel displacement experiments were carried out with different permeability differential cores. Experimental results show that the flow rate increases with flooding pressure increase,which increase faster in high permeability cores than in low permeability cores; the rate differential is significantly larger than permeability differential; the flow rate differential and oil displacement efficiency increase with permeability differential increase; the greater the permeability differential,the greater the start- up pressure in low permeability layers,low permeability layers is more difficult to produce. In multilayered reservoir development together,high and low permeability reservoir should be reasonably divided to produce efficiently.