Reduced Emission In Situ Oil Sands Recovery Processes

加拿大西部重油和沥青可采储量约1700亿桶，价值数万亿美元。由于稠油的原位粘度通常为数千至数万厘泊，油砂的粘度通常为数十万至数百万厘泊（水的粘度为1厘泊），因此这些资源的开采过程面临着严峻的挑战。与常规采油工艺相比，油砂采油工艺的能量和排放强度较高；因此，在全球舞台上，由于重油和沥青的高能量和排放强度，它们作为液体化石燃料似乎相对没有吸引力。为了维持社会许可，油砂开采的能源和环境效率必须等于或低于常规石油。申请人之前的NSERC DG的结果表明，油砂的开采过程不仅是物理的，油的粘度在蒸汽加热下降低，而且是由蒸汽-油和蒸汽-岩石反应引起的化学反应。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CO2和H2S，因此总排放强度既包括蒸汽产生的CO2，也包括反应产生的CO2。氧燃料燃烧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，并在开采石油时发现将地层内注入和生成的二氧化碳矿化的方法，则采收率过程将实现零二氧化碳排放。该研究计划的目标是确定一套蒸汽开采过程的操作条件和注入策略，在这种情况下，随着开采过程的发展，所有产生的二氧化碳（无论是蒸汽产生的还是原位产生的）和H2S（来自原位水热裂解）都将作为固体封存在储层中。该研究项目包括理论和实验两部分，旨在了解CO2和H2S在砂基质中转化为固体形态的动力学，并利用研究结果寻找新的操作条件和注入策略，以最大限度地提高CO2和H2S的固排量、产油量和采收率。在为期5年的研究项目中，将为10名HQP（2名博士，3名硕士，5名理学士）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).**