BEIJING, September 9, 2022 /PRNewswire/ — Modern societies are still very dependent on oil and gas resources for their smooth functioning. However, natural resources of oil and gas are finite and non-renewable. To keep up with the growing demand for hydrocarbons, we must find and secure alternative sources of natural oil and gas. Fortunately, a vast and largely untapped supply of oil and gas awaits beneath us.
Oil shale is a flaky sedimentary rock with a high organic content. When low-maturity oil shale is heated for extended periods of time, its organic molecules break down through pyrolysis and are transformed into lighter and more useful oil and gas. This forms the basis of a promising strategy known as on the spot upgrade (ISU), in which heating wells are drilled and laid directly in the shale layer to provide the necessary heat for pyrolysis. Hydrocarbons produced on site are then recovered through a separate production well. Although the process is technically feasible, there is no consensus as to whether it is economically feasible.
To address this knowledge gap, a research team at Northeast University of Petroleum, China and China University of Petroleum in East China recently conducted research on ISU technology. Led by Dr. Li Wenbiao from Northeast University of Petroleum, the team analyzed the economic feasibility of the ISU in terms of energy consumption ratio (ECR). Simply put, ECR is a measure of how much of the energy supplied to heating wells is used for pyrolysis relative to the energy lost to heat diffusion and absorption in minerals, water, and surrounding rocks.
As described in their paper published in Frontiers of Earth Science, the team used a geological model to look at the factors that most influence ECR. In their model, they account for the design and layout of heating wells, heating technology and shale composition, among other parameters and variables. A video summary of this study is now available on YouTube. Also visit the press release website: https://www.earthsciencefrontiers.net.cn/EN/news/news31.shtml
The results of their analysis show that appropriate spacing between heating and production wells is critical to improving ISU efficiency. The team also determined the minimum total organic content in oil shale that results in acceptable ECR values. In addition, they also compare and contrast new heating methods to increase ISU efficiency beyond the conventional heating wire approach. “One important way to increase the efficiency of ISU is to explore alternative heating technologies, such as convection and electromagnetic heating,Dr. Wenbiao emphasizes.
Overall, the team hopes that the results of their study will help pave the way for an economically viable ISU technology. “We want our results to encourage the application of ISU technology for optimized oil shale exploitation,” says Dr. Wenbiao.
Let us hope that his vision will soon become a reality and that low maturity oil shale will become a reliable source of hydrocarbons to meet our energy needs.
Original Article Title: Economic Feasibility and Performance Improvement Approaches for In Situ Upgrading of Low Maturity Organic-Rich Shales from an Energy Demand Factor Perspective
Journal: Frontiers of Earth Science
SOURCE Earth Science Frontiers