Techno-Environmental Evaluation of Exothermic Reactions of Cyclic Steam Injection: Accelerating the Implementation of Low-Carbon IOR/EOR Methods in Venezuela

This article presents a techno-environmental feasibility study of non-conventional steam generation through exothermic reactions with hydrogen peroxide (H₂O₂) in portable reactors, as a sustainable alternative to conventional steam generation methods in Cyclic Steam Stimulation (CSS), utilizing the Orinoco Oil Belt in Venezuela as a case study, characterized by vast reserves of highly viscous crude oil within unconventional reservoirs, where CSS is widely applied with remarkable success. Key factors for technological substitution are considered, particularly a significant number of promising CSS wells located in areas without readily available fuel gas and water supply infrastructure, as well as the need for more energy-efficient Improved/ Enhanced Oil Recovery (IOR/EOR) methods with a lower carbon footprint. To evaluate the potential of non-conventional steam generation using H₂O₂ for CSS, a two-step approach was employed. First, a comprehensive review of the available state-of-the-art in H₂O₂-based steam generation technologies was conducted, providing context for the evaluation of a specific surface steam generation scheme utilizing a portable reactor. Subsequently, a comprehensive review of the chemical reactions underlying the exothermic decomposition reaction of H₂O₂ was conducted. Analytically, the requirements for H₂O₂ and the reagent were estimated for steam generation under typical Orinoco Oil Belt operational conditions (5000, 7500, and 10000 t/cycle), considering its ability to achieve 100% steam quality as a key advantage of this technology. Finally, a comparative analysis was performed between H₂O₂-based and conventional steam generation for CSS, including factors such as thermodynamic properties, energy efficiency, carbon footprint, design/operation requirements, and safety considerations. This study presents a comprehensive analysis of technological options for unconventional steam generation using H₂O₂. A promising near-term approach is a portable device where steam is generated through a controlled exothermic chemical reaction (catalyzed) using surface equipment. The generated steam would be injected downhole, similar to conventional CSS. A model of the governing chemical reaction was developed to estimate the required reactant quantities (stoichiometry) and predict both the conversion of H₂O₂ to steam and the reaction's temperature profile. The results suggest that H₂O₂-based steam generation offers a potentially more favorable energy balance compared to conventional methods, with greater energy efficiency and a reduced carbon footprint. However, for widespread adoption of this technology, the availability and cost of H₂O₂, along with the potential environmental impacts of large-scale H₂O₂ production and transportation, require careful considerations which is the subject of phase two of this project. This work offers valuable insights for evaluating the feasibility of replacing conventional steam generation with H₂O₂-based steam in IOR/EOR applications. By demonstrating the potential for improved energy balance, efficiency, and reduced carbon footprint, this work contributes significantly to the pursuit of more sustainable and environmentally friendly oil recovery methods. Upon wide implementation, this technology provides a significant step towards 2050 net-zero set objective.