底水稠油油藏单井条件下隔夹层参数研究

Study on Interlayer Parameters of Bottom Water Heavy Oil Reservoir Under Single-well Condition

开发底水稠油油藏的主要问题在于底水的脊进,利用水平井开采可以有效地缓解这一开发矛盾。同时,隔夹层的存在能够大大减缓底水上升,提高采出程度,改善开发效果。讨论了单井条件下,隔夹层参数变化对开发效果的影响。影响开发效果的隔夹层因素较多,根据调研,并考虑到典型性和可行性,选取无因次隔夹层面积、无因次隔夹层垂向位置、隔夹层渗透率这3个参数进行隔夹层对开发效果影响的研究。基于渤海A油藏实际参数建立了含隔夹层的底水稠油油藏数值模型,通过油藏工程方法对采出程度曲线、含水上升曲线、流线模型场图和饱和度场图进行了分析,研究了单因素对开发效果的影响:无因次隔夹层面积越大,开发效果越好;隔夹层越靠近油水界面,开发效果越好;夹层渗透率较小时,开发效果优于隔层。在单因素影响分析的基础上,进行了正交实验,分析了多因素之间的影响,确定了3个参数的影响程度排序:由大到小依次为无因次隔夹层面积、无因次隔夹层垂向位置和隔夹层渗透率。

The main problem during the production of bottom water heavy oil reservoirs is the imbibition of the bottom water.The use of horizontal wells can effectively alleviate this production contradiction. At the same time, the existence of the interlayer can greatly reduce the rise of the bottom water, improve the recovery extent, and improve the recovery efficacy. This paper discusses the effect of the change of interlayer parameters on the production under the condition of a single well. There are many interlayer factors affecting the recovery efficacy. According to research, and considering the typicality and feasibility, three parameters, including the interlayer dimensionless area, interlayer dimensionless vertical position, and interlayer permeability,were selected for the study of the effect of interlayer parameters on production efficacy. Based on the actual parameters of the Bohai A reservoir, the numerical model of the bottom water heavy oil reservoir with interlayer was established. The production curve, water saturation rising curve, streamline field model diagram, and saturation field diagram were analyzed by the reservoir engineering method. The effect of each single factor on the production was studied: a larger interlayer corresponded to better production. The closer the interlayer is to the oil-water interface, the better the production is. The production in the case of an interlayer with low permeability is better than that in the case of a barrier. Based on the single-factor influence analysis, the orthogonal experiment was carried out, and the influence due to multiple factors was analyzed. The influence degree of the three interlayer parameters was determined. In decreasing order of influence, the parameters are: interlayer dimensionless area,interlayer dimensionless vertical position, and interlayer permeability.