对高温地热井的水泥复合材料的评估
Tatiana Pyatina1, Toshifumi Sugama1, Al Moghadam2
1Brookhaven National Laboratory, Upton, NY 11973, USA.
Materials (Basel, Switzerland)
|March 28, 2024
概括
与普通波特兰水泥 (OPC) 相比,基于酸水泥 (CAC) 的复合材料在高温地热井中表现出优越的耐用性. 随着时间的推移,CAC配方得到了改进,而OPC则降解,确保了长期的井 integrity.
科学领域:
- 地热能源工程 地热能源工程
- 材料科学 材料科学 材料科学
- 土木工程 土木工程是指土木工程.
背景情况:
- 高温 (HT) 地热井需要耐用的水泥复合材料,以确保长期的运行完整性.
- 恶劣的井口条件需要超越传统水泥混合物的先进材料.
研究的目的:
- 为HT井应用全面评估地热水泥复合材料.
- 为了比较基于酸水泥 (CAC) 的复合材料与普通波特兰水泥 (OPC) /混合物的性能.
- 开发一个数值模型来预测水泥的行为.
主要方法:
- 实验室测试包括循环压力功能的测试.
- 在高温地热井 (300-350°C) 中进行现场暴露测试.
- 材料特征:晶体组成,热重力学分析,元素分析,形态学,多孔性和机械性能.
- 使用修改的Cam-Clay (MCC) 可塑性参数进行数值建模.
主要成果:
- 基于CAC的复合材料在实验室和实地测试中显著超过了参考OPC/混合物.
- 参考OPC/混合物在9个月暴露期间由于HT碳化而失去机械性能.
- 基于CAC的混合物在同一暴露期内显示出更好的性能.
- 对于HT水泥配方,MCC可塑性参数被提取并验证.
结论:
- 基于CAC的水泥复合材料非常适合建造持久的HT地热井.
- 这些先进的材料提供优越的长期稳定性和性能,与传统的OPC/混合物相比.
- 开发的数值模型可以预测地热井中的水泥的完整性.
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