稠油油藏非均质性对火烧油层开发效果的影响

Development influence on heterogeneity by in-situ combustion in heavy oil field

由于油藏非均质性的存在,稠油油藏在不同注采方式下火烧油层开发效果存在较大差异。基于某油藏沉积微相分布特征,提出了3类非均质油藏概念地质模型,采用油藏数值模拟方法,建立了3类18个油藏模型,研究了油藏非均质性对火烧油层不同注采方式下开发效果的影响。结果表明:同一模型在同样的生产控制条件下,不同注采方式间的初期产油量和累积产油量之间存在差别;对于渗透率平面非均质性,高采低注火烧油层的开发效果优于高注低采;对于砂体厚度平面非均质性,厚采薄注火烧油层的开发效果优于厚注薄采;对于砂体形态非均质性,宽采窄注火烧油层的开发效果优于宽注窄采。敏感性分析结果表明,砂体形态非均质性对火烧油层开发效果的影响程度最大,厚度非均质性次之,渗透率非均质性的影响程度最小。因此,只有合理部署注采井位,才能有效地提高强非均质性稠油油藏火烧油层的开发效果。

In-situ combustion is one of the effective methods used for heavy crude oil. The reservoir heterogeneity is bound to affect the development performance. Three kinds of heterogeneous model including permeability, thickness and geometry form are proposed based on the distribution characteristics of the sedimentary micro-facies of certain reservoir. Then, 18 reservoir simulation models are built by applying the method of reservoir numerical simulation. The development effectiveness of injection-production pattern caused by heterogeneity is studied. The research result shows that the initial and cumulative production is different due to different injectionproduction pattern at the same condition. In order to improve the development effectiveness of in-situ combustion, the injection-production pattern should be optimized. And, the impact of geometry form is the biggest, thickness secondly, then the permeability.