水驱高效开发注采策略优化

Injection-production strategies optimization for efficient development of water flooding

水驱是一次采油后常用的提高采收率技术,但是由于地层非均质性的影响,致使注入水沿高渗层位突破而圈闭未波及到的原油.为了改善此类问题,提出了一种新的优化控制模型,其目标是调控各井的注采量,延缓水驱指进现象,尽可能多地采出原油.该模型是基于油藏数值模拟与优化理论构建的,通过控制变量的梯度求解,根据不同的需求,优化多个目标策略方案(如以累产油、累产水及经济效益为目标的最优方案),用以辅助油田生产决策.在理论方法研究的基础上,采用该模型对油藏实例进行了优化计算与分析,结果表明:获得的最优生产方案符合油田实际,为油田开发的智能调控提供了理论和技术支撑.

Water flooding is a common technique to improve recovery ratio after primary depletion.But because of heavy formation heterogeneity,injected water usually breaks through along the high permeability layer so as to trap crude oil in the bypassing regions.In order to solve such problems,this article proposed a optimal control model,and its goal was to delay fingering phenomenon of water flooding and produced crude oil as much as possible by controlling flow rate of injectors and producors.The author constructed the model on the basis of reservoir simulation and optimization theory.Through solving the gradients of control variables,strategy programs with the multiple objectives would be optimized（For example, objectives of these programs are respectively field oil production total,field water production total or economic benefits） to assist production decision-making of oil field.Based on the above theoretical study, applied examples of reservoir were optimized and analyzed.The results show optimal production scheme are coincident with the demand of actual field and it will provide a strong theoretical basis and technical support for smart field system.