储层流体非均质性对加拿大油砂热采的影响  

Influence of fluid heterogeneity on SAGD in Canadian oil sands

作　　者：谢华锋[1,2] 王健[3] 黄海平[1,4] 张伟[1] 

机构地区：[1]中国地质大学(北京)地球科学与资源学院,北京100083 [2]中国地质调查局油气资源调查中心,北京100029 [3]中国石化石油勘探开发研究院,北京100083 [4]卡尔加里大学地球科学学院

出　　处：《油气地质与采收率》2016年第6期94-98,104,共6页Petroleum Geology and Recovery Efficiency

基　　金：国家科技支撑计划"非常规油气评价技术及装备研究"(2006BAB03B08)

摘　　要：加拿大是世界上油砂资源最为丰富的国家,其中约80%的资源需要通过热采方式采出,目前应用比较广泛的热采技术包括蒸汽辅助重力泄油和蒸汽吞吐等。油砂热采的油藏模拟结果与生产历史难以拟合是面临的主要难题之一。分析发现,西加拿大沉积盆地范围内原油物性在横向和垂向上变化较大,油藏底部和顶部原油物性完全不同。重点对原油粘度垂向梯度变化对热采开发效果的影响进行油藏模拟研究,发现粘度梯度变化是造成油藏模拟结果与生产历史难以拟合的主要原因,采用变粘度模型模拟的累积产油量与实际生产数据吻合较好,采用定粘度模型的模拟结果偏高。利用变粘度模型对研究区的生产井位置优化结果显示,将蒸汽辅助重力泄油生产井部署在油水界面之上8 m处油层的动用程度和经济效益最大。将储层流体非均质性(特别是粘度非均质性)与储层岩石非均质性相结合,并应用于油藏描述和数值模拟中,能够准确预测油砂热采的生产动态及开发效果,优化生产管理,确保采收率和经济效益的最优化。Canada is the country with world largest oil sands resource,where 80% of the resources need to be produced by thermal recovery methods. The methods used widely include steam assisted gravity drainage(SAGD)and cyclic steam stimulation(CSS). The mismatch between reservoir simulation results and history production is one of the main challenges.Studies suggest that the large-scale lateral gradient change in the western Canadian sedimentary basin and small-scale vertical gradient change within the oil reservoir are very common for the composition and physical properties of crude oil and that the composition and properties of crude oil on bottom and top of oil reservoir are completely different. Reservoir simulation study was conducted on effects of the variation of viscosity gradient of crude oil on the thermal production. The results show that the viscosity gradient change is the main reason for mismatch between reservoir simulation results and production history. However,variable viscosity model can be used to predict cumulative oil production more accurately. And the prediction result of fixed viscosity model is too optimistic. Case studies on production well position optimization with variable viscosity model have shown the best produced degree and economic benefits should be 8 m above oil-water interface for ASGD. Heterogeneity of reservoir fluids,especially viscosity heterogeneity,and heterogeneity of reservoir rocks was combined and was applid to reservoir description and numerical simulation,which can predict accurately production dynamicsand development effect of oil sand thermal recovery,optimize production management and ensure the best recovery efficiency and economic benefits.

关 键 词：流体非均质性 粘度梯度 数值模拟 蒸汽辅助重力泄油 蒸汽吞吐 生产井部署 加拿大油砂 

分 类 号：TE345[石油与天然气工程—油气田开发工程]