Exploring in-situ combustion effects on reservoir properties of heavy oil carbonate reservoir  

作　　者：Aliya Mukhametdinova Tagir Karamov Strahinja Markovic Andrey Morkovkin Aleksander Burukhin Evgeny Popov Zi-Qi Sun Ren-Bao Zhao Alexey Cheremisin 

机构地区：[1]Skolkovo Institute of Science and Technology(Skoltech),Sikorskogo 11,Moscow,121205,Russia [2]State Key Laboratory of Petroleum Resources and Engineering,China University of Petroleum(Beijing),Beijing,102249,China

出　　处：《Petroleum Science》2024年第5期3363-3378,共16页石油科学（英文版）

基　　金：supported by the Ministry of Science and Higher Education of the Russian Federation under agreement No.075-10-2022-011 within the framework of the development program for a world-class Research Center。

摘　　要：Laboratory modeling of in-situ combustion is crucial for understanding the potential success of field trials in thermal enhanced oil recovery(EOR) and is a vital precursor to scaling the technology for field applications. The high combustion temperatures, reaching up to 480℃, induce significant petrophysical alterations of the rock, an often overlooked aspect in thermal EOR projects. Quantifying these changes is essential for potentially repurposing thermally treated, depleted reservoirs for CO_(2) storage.In this study, we depart from conventional combustion experiments that use crushed core, opting instead to analyze the thermal effects on reservoir properties of carbonate rocks using consolidated samples. This technique maintains the intrinsic porosity and permeability, revealing combustion's impact on porosity and mineralogical alterations, with a comparative analysis of these properties pre-and post-combustion. We characterize porosity and pore geometry evolution using low-field nuclear magnetic resonance, X-ray micro-computed tomography, and low-temperature nitrogen adsorption. Mineral composition of the rock and grain-pore scale alterations are analyzed by scanning electron microscopy and X-ray diffraction.The analysis shows a significant increase in carbonate rocks' porosity, pore size and mineral alterations, and a transition from mixed-wet to a strongly water-wet state. Total porosity of rock samples increased in average for 15%-20%, and formation of new pores is registered at the scale of 1-30 μm size.High-temperature exposure results in the calcite and dolomite decomposition, calcite dissolution and formation of new minerals—anhydrite and fluorite. Increased microporosity and the shift to strongly water-wet rock state improve the prospects for capillary and residual CO_(2) trapping with greater capacity.Consequently, these findings highlight the importance of laboratory in-situ combustion modeling on consolidated rock over tests that use crushed core, and indicate that depleted combustion stimula

关 键 词：In-situ combustion Thermal EOR CARBONATES Porosity and pore size MICROCT NMR SEM CO_(2)storage 

分 类 号：TE345[石油与天然气工程—油气田开发工程]