Towards Net-Zero Emissions: mechanics, processes and materials to support risk-based well decommissioning

加拿大净零排放责任法案于2021年6月29日成为法律。排放重点的很大一部分是针对工业排放，特别是碳氢化合物能源行业的排放。在这里，我们将重点放在油气井排放以及为减少或消除泄漏而进行的油井作业上。在加拿大西部，每年都会有1000口S油井永久退役。井眼的长期密封要求正确放置密封材料，避免污染/混合，并确保水泥与钢材和围岩具有良好的水力粘结。当它们发生在地表以下时，每一个都是物理上复杂的，很难预测和/或测量。行业最佳做法和监管要求需要以复杂的定义机制、流动过程和材料性能的科学知识以及实地数据、测量和监测为基础。该项目将基础知识作为其目标。本项目建立在三所加拿大大学和工业伙伴之间的长期合作基础上(第一阶段)。第二阶段建立在第一阶段的成功基础上，并与行业和监管参与者之间的共识所确定的知识差距和政策问题保持一致。该项目使用第一阶段建立的基础设施，涉及五个互补领域的子项目：(I)倾倒捞油和离底塞子放置，(Ii)清理套管后面和挤压固井，(Iii)井漏，(Iv)机械和材料，以及(V)社会影响和废弃替代方案。我们的团队将进行这些相互关联的研究，解决良好的遗弃知识差距，同时利用实验、分析和计算相结合的方法，以及实地调查工作和数据建模，提供根本的进展。总体目标是开发能够对不同做法进行量化评估的理解和工具。这使得行业和监管者能够制定基于风险的法规和做法。

The Canadian Net-Zero Emissions Accountability Act became law on June 29th, 2021. A large part of the emissions focus has targeted industrial emissions, particularly from the hydrocarbon energy industry. Here we focus at oil and gas well emissions and those well operations that are performed to reduce or eliminate leakage. Permanent decommissioning of 1000's of wells occurs annually in Western Canada. Long term sealing of wellbores requires proper placement of sealing materials, avoidance of contamination/mixing and ensuring a good hydraulic bond of the cement to both steel and surrounding rock. Each of these are physically complex and difficult to predict and/or measure as they occur below surface. Industry best practices and regulatory requirements need to be based on scientific knowledge of the complex defining mechanics, the flow processes and materials performance, as well as on field-based data, measurement and monitoring. This project delivers the underlying knowledge as its objectives. The present project builds on a long-term collaboration among three Canadian universities and industrial partners (Phase I). Phase II builds on the success of Phase I and is aligned with knowledge gaps and policy issues identified by a consensus between industrial and regulatory players. The project uses infrastructure established in Phase I and addresses sub-projects in five complementary areas: (i) dump bailing & off-bottom plug placement, (ii) cleaning behind casing & squeeze cementing, (iii) well leakage, (iv) mechanics &materials, and (v) societal impacts and abandonment alternatives. Our team will conduct these interlinked studies, addressing well abandonment knowledge gaps while providing fundamental advances using combined experimental, analytical and computational methods, along with field survey work, data modelling. The overall aim is to develop understanding and tools that allow quantitative assessment of different practices. This allow the development of risk-based regulations and practices by industry and regulators.