Reduced Emission In Situ Oil Sands Recovery Processes

加拿大西部重油和沥青的可开采量约为1700亿桶，价值数万亿美元。这些资源的开采过程面临严峻挑战，因为它们的原地粘度对于重油来说通常是几千到几万厘米泊，对于油砂来说通常是几十万到几百万厘米泊(水的粘度是1厘米泊)。与传统石油工艺相比，油砂回收过程的能量和排放强度较高；因此，在全球舞台上，重油和沥青作为液体化石燃料似乎相对没有吸引力，因为它们的能量和排放强度很高。为了保持社会经营许可证，油砂开采的能源和环境效率必须等于或低于传统石油。申请人以前的NSERC DG的结果表明，油砂回收过程不仅是物理过程，其中石油粘度在基于蒸汽的加热下降低，而且还包括蒸汽-油和蒸汽-岩石反应产生的化学反应过程。发生的反应包括水热裂解(含水热解)、热裂解(热解)和蒸汽-水-岩石的地球化学反应。关键问题是，产生的气体不仅包括溶解气体(主要是CH4)，还包括反应产生的二氧化碳和硫化氢，因此总排放强度既包括蒸汽产生的二氧化碳，也包括反应生成的二氧化碳。燃烧氧气的直接接触蒸汽发生器在燃烧器火焰中产生蒸汽，产生蒸汽-二氧化碳混合物。因此，如果将蒸汽产生的二氧化碳注入地层，并发现了一种在生产石油时将注入的和产生的二氧化碳在地层中矿化的方法，则回收过程将实现零二氧化碳排放。拟议研究计划的目标是确定一套基于蒸汽的采油过程的操作条件和注入策略，在这种过程中，所有产生的二氧化碳，无论是来自蒸汽还是来自现场产生的二氧化碳，以及来自原位水热分解的硫化氢，随着回收过程的发展，都以固体的形式隔离在储油层中。该研究计划包括理论和实验项目，以了解在砂岩基质中二氧化碳和硫化氢转化为固体的动力学，并利用结果寻找新的操作条件和注入策略，以最大限度地提高二氧化碳和硫化氢的封存、产油率和采收率。在5年的研究计划中，它将为10名HQP(2名博士、3名硕士和5名理科学生)提供全面的培训。

The recoverable volume of heavy oil and bitumen in W. Canada is ~170 billion barrels with value in the trillions of dollars. Serious challenges face recovery processes for these resources due to their in situ viscosities which are typically thousands to tens of thousands of centipoise for heavy oil and hundreds of thousands to millions of centipoise for oil sands (water has viscosity 1 centipoise). The energy and emissions intensities of oil sand recovery processes are high compared to conventional oil processes; thus, on a global stage, heavy oil and bitumen appear relatively unattractive as liquid fossil fuels given their high energy and emissions intensities. To maintain a social license to operate, the energetic and environmental efficiencies of oil sands extraction must be equal or lower than that of conventional oil. Results from the applicant’s previous NSERC DG revealed that oil sands recovery processes are not only physical ones where oil viscosity decreases under steam-based heating but also chemically reactive ones that result from steam-oil and steam-rock reactions. The reactions that occur include aquathermolysis (hydrous pyrolysis), thermal cracking (pyrolysis), and steam-water-rock geochemical reactions. The key issue is that the produced gases not only include solution gas (mainly CH4) but also CO2 and H2S from the reactions and thus the total emission intensity includes both CO2 from steam generation and reaction-based CO2. Oxyfuel-fired direct contact steam generators produce steam within the burner flame producing a steam-CO2 mixture. Thus, if CO2 from steam generation is injected into the formation and a means was discovered to mineralize both injected and generated CO2 within the formation as the oil is produced, the recovery process would have zero CO2 emissions. The objective of the proposed research program is to determine a set of operating conditions and injection strategies for steam-based recovery processes where all of the generated CO2, whether from steam or in situ generation, and H2S (from in situ aquathermolysis) is sequestered as solid in the reservoir as the recovery process evolves. The research program consists of both theoretical and experimental projects to understand the kinetics of conversion of CO2 and H2S to solid form in a sand matrix and to use the results to find new operating conditions and injection strategies to maximize CO2 and H2S sequestration, oil rates and recovery factor. Over the 5-year research program, it will provide comprehensive training to 10 HQP (2 PhD, 3 MSc, and 5 BSc students).