弹塑性油藏注采渗流场分布及储量有效动用规律  

Study on distribution of injection-production flow fields and laws of effective reserve production in elastoplastic reservoirs

作　　者：秦立峰 陈民锋 付世雄[1,2] 荣金曦 QIN Lifeng;CHEN Minfeng;FU Shixiong;RONG Jinxi(State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum(Beijing),Beijing City,102249,China;College of Petroleum Engineering,China University of Petroleum(Beijing),Beijing City,102249,China)

机构地区：[1]油气资源与探测国家重点实验室中国石油大学(北京),北京102249 [2]中国石油大学(北京)石油工程学院,北京102249

出　　处：《油气地质与采收率》2022年第3期128-136,共9页Petroleum Geology and Recovery Efficiency

摘　　要：一般弹塑性油藏存在启动压力梯度和压力敏感效应,使得开发过程中渗透率发生变化,因此,其渗流特征和储量有效动用规律与常规油藏相比存在很大差异,导致常规井网井距设计方法不能满足实际开发需求。基于经典渗流力学理论,建立典型注采井网条件下考虑压力敏感效应、启动压力梯度影响的渗流模型,并采用稳定逐次替换法得到注采渗流场分布规律;根据弹塑性油藏特点,建立储量有效动用效果的评价方法,得到不同条件下储量有效动用界限。结果表明,受到压力敏感、启动压力梯度的影响,注采单元中的储量动用范围、有效动用强度存在明显的变化;在给定油藏开发条件下,确定了储量有效动用界限,并计算得到满足储量有效动用目标的注采井距变化图版,可为油田井网优化设计提供理论依据。Generally,elastoplastic reservoirs have threshold pressure gradients and pressure-sensitive effects that can change the permeability during development.Therefore,their flow characteristics and the effective production laws of re⁃serves are dramatically different from those of conventional reservoirs,and the design methods for conventional well pat⁃terns and spacing cannot meet the actual development requirements.Based on the traditional mechanics of fluid flow in po⁃rous media,a flow model considering the influence of the pressure-sensitive effects and threshold pressure gradients was built with the typical injection-production well pattern,and the distribution law of injection-production flow fields was ob⁃tained using the steady successive substitution method.According to the characteristics of elastoplastic reservoirs,an evalu⁃ation method for the effective production effect of reserves was proposed,and the effective production limit of reserves un⁃der different conditions was obtained.The results show that the production range and effective production intensity of re⁃serves in injection-production units have obvious changes under the influence of pressure sensitivity and threshold pres⁃sure gradients.In given reservoir development conditions,the limit of effective reserve production is determined,and the change chart of inject-production well spacing that can achieve the target of effective reserve production is obtained through calculation,providing a theoretical basis for the optimization design of well patterns in oilfields.

关 键 词：弹塑性油藏 压力敏感 启动压力梯度 有效驱动压力梯度 有效动用 注采井距界限 

分 类 号：TE348[石油与天然气工程—油气田开发工程]