Analysis of Mechanisms and Environmental Sustainability in In Situ Shale Oil Conversion Using Steam Heating: A Multiphase Flow Simulation Perspective

Shale oil as an unconventional energy source holds significant extraction value. However, traditional extraction techniques often entail significant environmental impacts, emphasizing the need for more sustainable and environmentally friendly methods. In situ conversion of shale oil using superheated steam fits this bill. Based on this, we used a new TFC coupling simulator to build a geological model, providing a comprehensive depiction of the evolution process of various elements during in situ conversion by steam, thereby investigating the feasibility of this method. The results show that based on the temperature distribution within the shale oil reservoir during the heating stage, the area between the heating well and the production well can be divided into five regions. In addition, the steam injected contributes to driving the oil. However, due to the relatively low energy density of the steam, a large amount of steam needs to be injected into the reservoir in order to attain the intended heating outcome, resulting in a high ratio of liquid water in the produced products. Meanwhile, the evolution of components during in situ conversion is influenced by factors such as the injection rate of steam and soaking time. A slow injection rate and prolonged soaking time are both adverse to extraction of shale oil. On this basis, the in situ conversion heating strategy can be refined.