基于数据空间反演的油藏实时生产优化方法

油藏开发实时优化调控技术是智能油藏研究的核心内容。提出了基于数据空间反演的油藏实时生产优化新方法,仅需若干油藏模型先验生产动态,基于贝叶斯理论构建代理模型,根据随机极大似然原理拟合历史观测数据进行模型训练,反演得到符合实际观测数据的生产动态后验估计。采用同步扰动随机逼近算法建立生产优化数学模型,实现注采参数实时优化,提高经济开发效益。该方法基于代理模型在拟合阶段避免了重复数值模拟计算,得到正确生产动态后验估计同时兼顾了油藏模型实际地质特征,优化所得方案考虑了目标油藏的不确定性,降低了实际生产开发风险。油藏实例应用表明:该方法能得到与常规多模型数据同化方法相一致的生产动态预测结果,拟合过程计算效率提高了5倍,且注采优化方案能取得良好的驱油效果。提出的油藏开发生产优化设计方法为油田实时生产优化提供了新的思路。

Optimization method for real-time reservoir production based on data space inversion

The real-time optimization control technology for reservoir development is a focus of the research of intelligent reservoirs This paper proposes a new method for real-time reservoir production optimization based on data space inversion.First,only a number of priori production dynamics from reservoir models are required to construct the proxy model based on Bayesian theory and then to perform model training by fitting of historical observation data based on the random maximum likelihood principle.Finally,the posteriori estimation of production dynamics conforming to the actual observation data can be obtained by inversion.Using a simultaneous perturbation stochastic approximation(SPSA),a mathematical model of production optimization has been established to realize the real time optimization of injection-production parameters and improve economic development benefits.On the basis of proxy model,this method avoids repeated numerical simulation calculations in the history matching stage,and obtains the posterior estimation of real production dynamics while considering the actual geological characteristics of reservoir model.The optimized scheme takes into consideration the uncertainties of reservoirs and reduces the risks of reservoir development.The actual application in oil reservoirs showed that the production forecast results of this method are consistent with those obtained by the conventional multiple model data assimilation method.The calculation efficiency of the history matching process has been improved by five times and good waterflooding effect has also been achieved using the injection production optimization scheme.The proposed production optimization method of reservoir development has provided new ideas for the real-time production optimization of oilfields.