Using 3D Printed Reservoir Rock Analogs to Validate Numerical Models

加拿大的自然资源工业通过原地工艺（如水平钻井）获取油砂、煤、沥青碳酸盐和页岩等能源。在这些操作期间，压力和温度的变化会影响密封和容纳能源的地球结构（盖层），这可能会危及操作和周围环境的安全。例如，2010年，一个浅层油砂储层上正在运行的蒸汽辅助重力泄油（SAGD）项目的盖层密封严重破裂，导致大爆炸，并在该地区形成一个75米x125米的地表火山口。2014年，另一个基于蒸汽开采的作业在盖层密封上出现了裂缝，导致沥青渗漏到地表。 能源监管机构和行业运营商依靠计算机模拟/数值模型和现场观察来防止盖层失效。然而，目前的计算机模型未能预测这些故障情况，强调需要在实验室中验证和改进现有的数值工具。拟议的研究将使用新型3D打印技术从沙子中创建大规模合成岩石，以研究模拟盖层在各种高压高温（HPHT）情况下的基本地质行为。将按照规范（即复制盖层的裂缝和断层）建造合成岩石，以确保样品与高压高温试验前的实际现场盖层相同。计算机模型预测在测试期间同时运行。物理测试结果与模型的预测进行了比较，以验证模型的准确性。通过这种测试，可以确定盖层的最大工作压力;这种工作压力决定了在开采作业期间什么样的压力水平是安全的，以及增加资源开采所需的最佳压力水平。 拟议的研究将提高能源回收项目的有效和安全运行，并协助改进油藏监测技术和生产优化活动。阿尔伯塔大学（UA）的研究人员、行业运营商和能源监管机构将更好地了解盖层的破坏机制（即导致破裂的过程）。UA研究人员还将改进现有的计算机模型和/或开发上级模型，供行业和监管机构使用，以优化加拿大能源资源的安全、经济和环境可持续回收。

Canada's natural resource industries access energy sources such as oil sands, coal, bitumen carbonates and shales through in situ processes (e.g. horizontal drilling). During these operations, changes in pressure and temperature affect the earth structures (caprock) that seal and contain the energy sources, which could compromise the safety of the operation and surrounding environment. For example, in 2010, the caprock seal of an operating steam-assisted gravity drainage (SAGD) project on a shallow oil sands reservoir was dramatically ruptured, resulting in a large explosion and the creation of a 75 m x 125 m surface crater in the area. In 2014, another steam extraction-based operation had a breach in the caprock seal, resulting in bitumen seepage to the surface. Energy regulators and industry operators rely on computer simulations/numerical models and field observations to prevent caprock failure. However, current computer models failed to predict these failure cases, highlighting the need to validate and improve existing numerical tools in the laboratory. The proposed research will use novel 3D printing technology to create large-scale synthetic rocks out of sand to study the fundamental geological behaviour of analogue caprock under various high-pressure high-temperature (HPHT) scenarios. Synthetic rocks will be built to specification (i.e. to replicate the caprock's cracks and faults) to ensure the samples are identical to the actual field caprock prior to HPHT testing. Computer model predictions are run simultaneously during the testing. The physical test results are compared to the model's predictions to validate the model's accuracy. From this testing, the maximum operating pressure for the caprock can be determined; this operating pressure dictates what level of pressure is safe during recovery operations as well as the optimal level of pressure to apply to increase resource recovery. The proposed research will enhance the efficient and safe operation of energy recovery projects and assist in improving reservoir surveillance techniques and production optimization activities. University of Alberta (UA) researchers, industry operators and energy regulators will better understand the failure mechanics of caprocks (i.e. the processes that lead to rupturing). UA researchers will also improve existing computer models and/or develop superior models for industry and regulator use to optimize the safe, economic and environmentally sustainable recovery of energy resources in Canada.