循环限制压力和岩石透性:机械压缩或细移迁移
Evgenii Vasilevich Kozhevnikov1, Mikhail Sergeevich Turbakov1, Evgenii Pavlovich Riabokon1
1Department of Oil and Gas Technologies, Perm National Research Polytechnic University, Perm, Russia.
Heliyon
|November 15, 2023
概括
循环负荷降低了岩石的透性,这是由于机械压缩和合物迁移. 体迁移显著影响表面透性,需要在核心测试中考虑.
科学领域:
- 石油工程是石油工程中的一个.
- 地质地质地质地质地质地
- 材料科学 是一种材料科学.
背景情况:
- 在循环负荷下,岩石的表面透性下降,主要归因于不可逆转的变形.
- 目前在循环负荷下测量透性的方法忽略了流体载体合物的影响.
- 体迁移对毛孔喉堵塞和随后的透性降低的影响在多孔岩石研究中经常被忽视.
研究的目的:
- 提供实验证据,表明合物迁移除了机械紧缩外,还会在循环加载时导致透性降低.
- 为了区分机械紧缩和合物迁移对明显透性变化的贡献.
- 突出在常规核心测试中合物迁移的重要性.
主要方法:
- 开发了一种新的方法,包括在装载/卸载周期之间用高压梯度清理核心样本.
- 在岩石核心样本上进行了多循环限制压力测试.
- 在不同气体流向和流程下测量了表面透率的变化.
主要成果:
- 岩石样本的表面透率降低了高达20%,这是由于循环负荷下的合物迁移造成的.
- 透性动态变得不可预测,并且在流动方向/模式发生变化时,显示出对限制压力的弱依赖.
- 在测试后的4个样本中,有3个样本的表面透率恢复到初始值,证实了合物迁移的影响.
结论:
- 合体迁移是影响周期性负荷和气体注入下的明显岩石透性的重要因素.
- 拟议的机制解释了气体注入和循环限制压力期间的明显透性变化.
- 体迁移必须纳入核心测试分析,包括常规核心泛滥和循环负荷测试.
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