摘要
目前确定低渗油藏合理注采井距的方法,主要以启动压力梯度为判断基础,而实际生产过程中两相渗流阻力也有影响.从渗流力学出发,考虑非活塞驱替两相流及启动压力梯度,分别以油相区、油水两相区及纯水区的渗流数学表达式为基础,得出基于两相渗流低渗油藏合理注采井距的新方法,并通过实例计算与结果对比证实其理论的合理性与可靠性.实例计算得出注采压差为40.0MPa,渗透率为1.0×10-3μm2时油藏合理注采井距为130m.考虑两相渗流确定的合理注采井距随渗透率增大而增大,但增长幅度随渗透率的增大而减缓,且渗透率与井距呈近似幂函数关系;随渗透率增大,新旧方法确定的井距相差越来越大,因此计算合理注采井距时,应考虑启动压力梯度与油水两相渗流阻力共同作用,以使其计算结果更加合理可靠.
At present,method of determination suitable injection-production spacing in low permeability reservoirs only based on start-up pressure gradient,but the well spacing is be influence by two phase flow resistance in actual production process.From seepage mechanics,considering the non-piston displacement and threshold pressure gradient,the new calculation method of reasonable well spacing in low permeability basing on two phase flow is be derived,as the foundation of oil,water-oil and water zone seepage mathematical expression,and the theory is be proved rationality and reliability through the calculation and comparison of example.The reasonable well spacing is 130 m of permeability 1.0×10-3 μm2 at 40 MPa injection-production pressure differential in the examples Results indicate that suitable injection-production spacing increases with the permeability considering two phase flow determine,but increase with the increase of permeability slow down,and the relationship between the reasonable well spacing and permeability is well simulated by power function;and with the permeability increase,the difference of two methods is growing,so when calculation reasonable well spacing,threshold pressure gradient and two phase flow should be considered and the result is more reasonable and reliable.
出处
《东北石油大学学报》
CAS
北大核心
2012年第4期45-48,115,共5页
Journal of Northeast Petroleum University
基金
中国海洋石油总公司"十二五"科技重大专项(CNOOC-KJ-125-ZDXM-07)
关键词
低渗油藏
启动压力梯度
水驱前缘
注采井距
两相流
非活塞驱替
low permeability reservoirs
threshold pressure gradient
water-flood front
injection-production spacing
two phase flow
non-piston displacement
