Electrical/Electromagnetic Enhanced Oil Recovery for Unconventional Reservoirs: A Review of Research and Field Applications in Latin America

Abstract

Abstract The exploitation of unconventional oil reservoirs with low environmental impact represents a big challenge nowadays, where considerable efforts are being focused on the production of clean fuels with low carbon content, and the energy transition to the net-zero carbon emissions. Electrical/electromagnetic Enhanced Oil Recovery (EEOR) processes have been considered emerging techniques that allow increasing mobility of crude oil along with reduced and low environmental impact, compared to well-known and established thermal techniques such as steam injection where significant volumes of water are required for steam generation, coupled with the high production of acid gases during these processes. This article presents an exhaustive review of the Electrical/electromagnetic EOR methods evaluated at laboratory scale or investigated by numerical simulations, mostly undertaken for deeper understanding of the associated physical phenomena, as well as specific field-scale applications for several unconventional reservoirs in Latin America. In this context, the main challenges associated with the implementation of the process mechanisms and the application of these technologies along with the evaluation of applicable ranges of related critical parameters will be highlighted, and the main conclusions of laboratory experiences or/and field condition cases will be captured in this article. Among the main results of this review, it is found that the application of Electrical/electromagnetic EOR/IOR methods offers advantages in increasing the mobility of crude oil without generation of high-water cuts as well as reduced H2S production, both having significant low impact environmental considerations. However, the common operational challenges and/or issues of these EOR techniques are related to process inefficiency due to the presence of high-water saturation, reservoir heterogeneities, electrical leakage, mechanical failures, tool's material characteristics, location of the heating, gas breakthrough and management of greenhouse gases, which pose limitations on the wide-spread use of these heating methods. The paper will discuss important underlying aspects of the electrical/electromagnetic EOR processes to evaluate the viability of applying these methods in unconventional Latin American reservoirs, emphasizing Venezuelan reservoirs, based on technical and economic evaluations worldwide, targeting production of fossil fuels with low environmental impact from the huge hydrocarbon reserves located in Venezuela, mainly in the Orinoco Oil Belt.