CO2貯蔵井戸におけるセメントシートの長期的な密封完結性の分析
Kaide Zhao1,2,3, Shuangjin Zheng4,5,6, Hu Meng1,2,3
1Hubei Key Laboratory of Oil and Gas Drilling and Production Engineering, Yangtze University), Wuhan, 430100, China.
Scientific reports
|February 13, 2026
まとめ
CO2の地質学的貯蔵の完全性は,セメントシート腐食によって脅かされています. 新しい機械モデルは,腐食と圧力が井戸口の密封にどのように影響するかを定量化し,リスクの増加を明らかにし,より良いCCUS井戸設計を告知します.
科学分野:
- ジオテクニカルエンジニアリング ジオテクニカルエンジニアリング
- 材料科学 材料科学とは
- 石油工学は,石油工学である.
背景:
- 二酸化炭素 (CO2) の地質学的貯蔵は,排出削減のための重要な炭素捕獲,利用,貯蔵 (CCUS) テクノロジーです.
- CO2の腐食と運用上のストレスにより,井戸掘削セメントシートの整合性が損なわれ,密封能力が脅かされます.
- 既存の研究は,セメントシート機械的反応分析における腐食とストレスによる結合効果をしばしば無視している.
研究 の 目的:
- 結合されたCO2の腐食とストレス効果を考慮して,セメントシートのための新しい理論的計算モデルを開発する.
- CO2の注入と貯蔵作業中に腐食したセメントシートのストレス-移動反応を定量化するために.
- CCUSプロジェクトにおける井戸掘削設計の最適化のための理論的基礎を提供すること.
主な方法:
- キャッシングが腐食したセメントシート成形装置の機械モデルを確立した.
- 弾性プラスチック理論,厚壁シリンダー理論,モール・クーロンブ基準を活用した.
- MATLABを使用してモデルを解いて,ストレス-移位行動とマイクロアヌルス開口を分析しました.
主要な成果:
- CO2の腐食は,ストレスの複雑性とセメントシートにおける密封不全のリスクを大幅に増加させます.
- 5mmの腐食した層は,60MPaの注入圧力下でマイクロアヌルスの開口を118%増加させた.
- カーシング壁の厚さの増加は,放射性ストレスとマイクロアヌルスの開口を効果的に軽減し,井戸穴の完全性を高めます.
結論:
- 開発されたモデルは,CO2の腐食がセメントシートシールに与える有害な影響を正確に予測しています.
- 腐食の深さは,腐食層の厚さよりも,マイクロアヌルスの開口により顕著な影響を及ぼします.
- CO2の地質貯蔵井戸における密封のリスクを軽減するために,蓋の壁の厚さを最適化することが重要です.
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