Wang Jinkai, Zhang Yuanpei, Xie Jun
College of Earth Science and Engineering, Shandong University of Science and Technology, Qingdao, 266590, China.
Laboratory for Marine Mineral Resources, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China.
Sci Rep. 2020 Feb 4;10(1):1839. doi: 10.1038/s41598-020-58792-z.
In recent years, large amounts of CO emissions have led to many environmental problems. Developing a reasonable approach to carbon dioxide emissions is one of the most important issues for the sustainable development of human civilization. Compared with CO geological storage, CO flooding has greater advantages and a higher utilization efficiency. CO flooding technology has been successfully applied to many types of reservoirs, such as conventional sandstone reservoirs, low-permeability reservoirs, and carbonates. In this paper, the feasibility of CO flooding in glutenite reservoirs is studied. First, the glutenite reservoir is divided into fine stages, and reasonable vertical development units are determined. On this basis, the distribution scale, genetic environment and formation mode of the glutenite reservoir are characterized in detail and their spatial distribution rules are depicted in three dimensions. Then, the influencing factors of CO flooding in the glutenite reservoir are analysed via reservoir numerical simulation technology. The effects of reservoir thickness, reservoir heterogeneity, macropores, dominant channels and fracturing on CO flooding efficiency are evaluated individually, and a set of reasonable parameters constituting an evaluation system for CO flooding in the glutenite reservoir is established. Finally, based on parameter optimization, the disadvantaged conditions of CO flooding in glutenite reservoirs are optimized, and their effects are gradually eliminated. In view of the characteristics of glutenite reservoirs, a unique three-dimensional well pattern arrangement is designed, different injection modes are optimized, and suitable injection agents are tested. These methods are conducive to improving the effect of reservoir parameters on CO flooding efficiency, allowing these reservoirs to be used for CO flooding. Based on these new methods, the displacement effect of the Yanjia-Yongan glutenite reservoir is predicted. Our results show that the reservoir has been developed efficiently and achieved a high recovery rate, the displacement front of the CO has become more uniform, and the sweep range has become wider. After extending the successful application of CO flooding in this reservoir to all of the glutenite reservoirs in the entirety of the Bohaiwan Basin, we predict that the oil recovery rate may reach 40%, with a cumulative oil recovery rate of approximately 3.04 × 10 t and a total CO consumption of 1.672 × 10 t. Thus, the proposed approach not only can improve the atmospheric environment but can also greatly improve the efficiency of oil displacement.
近年来，大量的一氧化碳排放导致了许多环境问题。制定合理的二氧化碳排放处理方法是人类文明可持续发展的最重要问题之一。与二氧化碳地质封存相比，二氧化碳驱油具有更大的优势和更高的利用效率。二氧化碳驱油技术已成功应用于多种类型的油藏，如常规砂岩油藏、低渗透油藏和碳酸盐岩油藏。本文研究了砂砾岩油藏二氧化碳驱油的可行性。首先，对砂砾岩油藏进行精细分层，确定合理的纵向开发单元。在此基础上，详细刻画了砂砾岩油藏的分布规模、成因环境和形成模式，并从三维角度描绘了其空间分布规律。然后，通过油藏数值模拟技术分析了砂砾岩油藏二氧化碳驱油的影响因素。分别评估了油藏厚度、油藏非均质性、大孔、优势通道和压裂对二氧化碳驱油效率的影响，建立了一套合理的参数，构成了砂砾岩油藏二氧化碳驱油评价体系。最后，基于参数优化，对砂砾岩油藏二氧化碳驱油的不利条件进行优化，逐步消除其影响。针对砂砾岩油藏的特点，设计了独特的三维井网布置，优化了不同的注入方式，并对合适的注入剂进行了测试。这些方法有利于提高油藏参数对二氧化碳驱油效率的影响，使这些油藏能够用于二氧化碳驱油。基于这些新方法，预测了杨家-永安砂砾岩油藏的驱替效果。结果表明，该油藏得到了高效开发，采收率较高，二氧化碳驱替前缘更加均匀，波及范围更广。将该油藏二氧化碳驱油的成功应用推广到渤海湾盆地全部砂砾岩油藏后，预计采收率可达40%，累计采油量约为3.04×10吨，二氧化碳总消耗量为1.672×10吨。因此，所提出的方法不仅可以改善大气环境，还可以大大提高驱油效率。
