Print Email Facebook Twitter Modeling rock damage during the long-term production process for hot dry rocks Title Modeling rock damage during the long-term production process for hot dry rocks: Effects of additional conductivity on the production performance and economic efficiency Author Xu, Fuqiang (China University of Petroleum - Beijing) Shi, Yu (Southwest Jiaotong University) Song, Xianzhi (China University of Petroleum - Beijing) Song, G. (TU Delft Applied Geology) Li, Shuang (China University of Petroleum - Beijing) Date 2023 Abstract Hot dry rocks (HDRs), as an essential renewable energy source, its development has received widespread attention, especially for heat extraction. The fracture is the main seepage and heat transfer channel of circulating fluid in dense HDR reservoirs, and its conductivity evolution significantly affects the production performance. Most existing studies have focused on the change of fracture conductivity under elastic deformation without considering the additional conductivity induced by rock damage. However, the additional conductivity may have significant implications for rational design and timely adjustment of the production scheme. Therefore, a three-dimensional model at the field-scale is established, and it is used to analyze the effect of additional conductivity on production performance and economic efficiency. To simplify the calculation, the actual forms of damage are equivalent to the macroscopic physical evolution of the matrix. Results show that the rock is mainly tensile failure affected by thermal stress during production. The occurrence of damage will increase the reservoir permeability and porosity, reduce Young's modulus, and then reduce the differential pressure and production temperature, with a maximum reduction of 2.21 MPa and 14.21 °C in the control case, respectively. The effects of injection temperature, Young's modulus, and injection mass flow on the production performance are significant, followed by Poisson's ratio. In contrast, production pressure and fracture initial permeability had less influence. The maximum differential economic benefit of the control case is up to 2.289 million RMB. This research proves the necessity of damage study during the long-term production of HDRs. Subject Additional conductivityEconomic efficiencyHot dry rocksLong-term productionProduction performanceRock damage To reference this document use: http://resolver.tudelft.nl/uuid:ab748942-3e9f-48fe-8eea-53d8e76dac77 DOI https://doi.org/10.1016/j.jclepro.2023.140298 Embargo date 2024-06-26 ISSN 0959-6526 Source Journal of Cleaner Production, 434 Bibliographical note Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public. Part of collection Institutional Repository Document type journal article Rights © 2023 Fuqiang Xu, Yu Shi, Xianzhi Song, G. Song, Shuang Li Files file embargo until 2024-06-26