Use of Tracers and Temperature to Estimate Fracture Surface Area for EGS Reservoirs
Use of Tracers and Temperature to Estimate Fracture Surface Area for EGS Reservoirs
复制标题
使用示踪剂和温度来估计 EGS 储层的裂缝表面积
DOI：
10.1016/j.geothermics.2016.12.006
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发表时间：
2017
期刊：
影响因子：
3.9
通讯作者：
A. Suzuki
中科院分区：
文献类型：
--
作者：
M. Shook;A. Suzuki
EGS 储层的设计和长期行为及其管理的一个关键不确定性是控制主岩与循环注入水之间传热速率的裂缝表面积。开发了一个工作流程，使用分析解决方案来估计该表面积。我们首先分析示踪剂测试，以估计扫过的裂缝孔隙体积、流动几何形状以及多个裂缝（或主裂缝周围的损伤区域）的存在。利用有关断裂特性的信息，可以迭代求解描述产生的温度与时间的解析解，以估计表面积。在多裂缝的情况下，我们证明了控制产出流体温度的方程可以叠加来估计表面积。即使存在异质性，该工作流程也显示出稳健性。然后，该工作流程用于制定有关储层可持续发展的设计决策和预测。还展示了使用工作流程来估计发电量作为裂缝特性（测量）和流量（控制）的函数，并展示如何扩大到多个生产井和裂缝充填。讨论了所使用的假设和该方法的局限性。
A key uncertainty in the design and long-time behavior of EGS reservoirs, and their management, is the fracture surface area that controls the rate of heat transfer between the host rock and the circulating injected water. A workflow is developed that uses analytic solutions to estimate this surface area. We first analyze a tracer test to estimate the fracture pore volume swept, the flow geometry, and the presence of multiple fractures (or damage zones around the primary fracture). Using this information about fracture properties, an analytic solution describing produced temperature vs. time can be solving iteratively to estimate surface area. In the case of multiple fractures, we show that the equation governing the produced fluids’ temperature is superposed to estimate the surface area. The workflow is shown to be robust, even in the presence of heterogeneity.The workflow is then used to make design decisions and predictions about the sustainably of a reservoir. Also shown is the use of the workflow to estimate power generation as a function of fracture properties (measured) and flow rates (controlled), and show how to scale up to multiple production wells and fracture packs. Assumptions used, and limitations of the method are discussed.