局限热循环对CCS具有不同的热力学性能的密封剂的影响
Kai Li1,2,3, Reinier van Noort4, Anne Pluymakers5
1Geoscience and Engineering Department, Delft University of Technology, Delft, The Netherlands. Kai.li@kit.edu.
Scientific reports
|September 17, 2025
概括
在地质二氧化碳储存中,密封剂的完整性至关重要. 这项研究发现,密封剂具有较高的抗拉强度和热扩散性,但具有较低的Young Young.
科学领域:
- 地质二氧化碳储存地质二氧化碳储存
- 材料科学 材料科学 材料科学
- 地质技术工程 地质技术工程
背景情况:
- 井口和岩石封的完整性对于永久的地质二氧化碳储存至关重要.
- 由于二氧化碳注入而产生的热循环可能会损害密封的完整性.
- 了解热应力下的密封剂特性是必不可少的.
研究的目的:
- 确定密封剂的关键特性,以在in-situ条件下承受热循环.
- 为了评估不同基于水泥的密封剂组合的性能.
- 为了评估封闭压力在热循环期间对密封剂行为的影响.
主要方法:
- 研究了四种密封剂组成 (两种普通波特兰水泥,一种新型水泥混合物,一种酸水泥).
- 具有特征的热力学特性 (Young 的模量,抗拉强度,热扩散性等). ) 的情况.
- 在120°C的三轴封闭 (1.5或10MPa) 下,受热循环 (20°C注水) 的密封剂.
- 使用X射线微型计算机断层扫描 (micro-CT),测量和压力强度测试来评估完整性.
主要成果:
- 所有密封剂在隔离下进行热循环后都保持完整,没有裂 (32微米以上).
- 由于压缩,所有密封剂的治疗后孔隙性都减少了,导致压力强度增加.
- 较高的限制 (10 MPa) 导致较大的孔隙减少和增强的压力强度,而1.5 MPa.
- 限制通过增加有效密封剂强度来抑制裂纹形成.
结论:
- 密封剂的特性对于承受热循环至关重要,包括高抗拉强度和热扩散性.
- 低的模量和热膨胀系数对于二氧化碳储存中的密封剂也是可取的.
- 隔离在热循环过程中显著提高密封剂性能和完整性.
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