基于示踪剂监测的水窜通道快速评价方法

A Fast Evaluation Method of Water Breakthrough Channels Based on Tracer Monitoring

目前常用示踪剂半解析解释方法,由于建模过程复杂,对示踪剂扩散系数等经验化处理,无法快速、准确提供水窜通道解释结果。基于示踪剂井间运移规律,采用降低维度的方法,将研究对象由整个注入层位集中至水窜通道,并建立示踪剂一维扩散模型,利用Laplace逆变换进行求解。在敏感性分析的基础上,快速调参,实现对井间水窜通道的定量解释。通过调整注入水突进速度、扩散系数、井筒稀释系数三个变量,拟合示踪剂实际产出曲线,获得目标井组的实际注入水突进速度、无效水循环比例、水窜通道体积等参数,形成一套井间水窜通道快速评价方法,与半解析方法对比发现,解释结果基本一致,证明了方法的可行性。

Tracer semi-analytical interpretation is a popular method to calculate parameters of water breakthrough channels. However, due to complex model building process and empirical treatment of tracer diffusion coefficient, the interpretation results cannot be supplied promptly and accurately. In this paper, through analysis of inter-well tracer moving law, the research dimensions were decreased from whole injection layer to water breakthrough channels. Then one-dimensional tracer plane diffusion model was built up based on diffusion theory, and it was solved by Laplace transform. By adjusting the parameters including water breakthrough velocity, diffusion coefficient and wellbore dilution coefficient, actual tracer output curve was matched; the actual water breakthrough velocity, invalid injection water ratio, volume of water breakthrough channels in target well group were obtained. The interpretation results of the method were basically in accordance those of semi-analytical method, which proved the feasibility of the method.