A systematic and careful analysis of changes in the magnitude of geomechanical parameters is essential to mitigate the risk of leakage from CO2 storage sites. However, depending on rocks and storage sites, these changes might be different due to chemical reactions taking place, especially when it comes to saline aquifers. There have only been few studies carried out in the past to evaluate the maximum sustained pressure of rocks being exposed to these chemical interactions. However, more studies are still required to evaluate the strength of the storage medium or seals when different kinds of rocks and fluids (fresh water or brine) are included in the hostile environment of a storage site. In this paper, attempts were made to evaluate changes in the variation of geomechanical parameters of the Berea sandstone during and after the injection of supercritical CO2 in a short period of time. The results obtained indicated that the presence of brine in the pore space during injection enhances the severity of geochemical reactions, causing reductions in the magnitudes of elastic parameters including shear modulus. Having a good look into the SEM images of the sample before and after exposure to scCO2 indicated that these changes can be attributed to the dissolution/fracturing of calcite and clays in the matrix of the sample. Although findings were provided based on the pulse measurements tests, more studies are required to have a deeper understanding as to how geochemical reactions may cause difficulties during and after injection into a storage site.
The Joule-Thomson (JT) phenomenon, the study of fluid temperature changes for a given pressure change at constant enthalpy, has great technological and scientific importance for designing, maintenance and prediction of hydrocarbon production. The phenomenon serves vital role in many facets of hydrocarbon production, especially associated with reservoir management such as interpretation of temperature logs of production and injection well, identification of water and gas entry locations in multilayer production scenarios, modelling of thermal response of hydrocarbon reservoirs and prediction of wellbore flowing temperature profile. The purpose of this study is to develop a new method for the evaluation of JT coefficient, as an essential parameter required to account the Joule-Thomson effects while predicting the flowing temperature profile for gas production wells. To do this, a new correction factor, C NM , has been developed through numerical analysis and proposed a practical method to predict C NM which can simplify the prediction of flowing temperature for gas production wells while accounting the Joule-Thomson effect. The developed correlation and methodology were validated through an exhaustive survey which has been conducted with 20 different gas mixture samples. For each sample, the model has been run for a wide range of temperature and pressure conditions, and the model was rigorously verified by comparison of the results estimated throughout the study with the results obtained from HYSYS and Peng-Robinson equation of state. It is observed that model is very simple and robust yet can accurately predict the Joule-Thomson effect.
In these downturn oil price occasions, the establishment of a numerical model may become a reward in the continually on-screen tracking of the challenging issues such as evaluation of zones flow contribution; investigation of alternative methods in lieu of well interventions and prediction of wellbore temperature profile in the operation of multi-zones producing wellbores. The new approach is based on energy, mass and momentum balance equations. The study briefly describes calculation of overall heat transfer coefficient which is based on the heat resistivity of different layers around a wellbore as well as the heat difference between wellbore and surrounding ground. A simplified numerical model is developed based on the overall heat transfer coefficient which accounts all modes of heat transferring mechanism. The model has been designed to predict wellbore temperature profile along a multi-zones production wellbore. The model explores wellbore temperature profiling both for single-phase and multi-phase production scenarios. The proposed model has been run for the prediction of wellbore temperature profile for a published oil producing well perforated along three different intervals with the contribution of all intervals in the production. Predicted temperature profile is successfully applied for the investigation of flow contribution of each layer considering key thermal characteristics of single- and multi-phase fluid flow along the wellbore. The predicted temperature profile has been compared with the real data; and a good agreement is demonstrated. This is important as it demonstrates that the proposed model can predict wellbore temperature distribution on a real-time basis to continuously monitor downhole temperature without performing well intervention or installing mechanical tools. Also, to explore the impact of flow rate and production string size on the wellbore temperature profile, sensitivity analyses have been carried out. It has been found that both flow rate and production string size may have a significant influence in the prediction of wellbore temperature profile. The major conclusion of sensitivity analysis of this study is that the higher production rates and smaller tubing sizes results a higher wellbore and wellhead temperature, which can be as a consequence of friction effect along the producing string. The novelty of this study is to develop a governing equation as well as to develop a computer simulator for evaluation of wellbore temperature and flow profiles along multi-zones producing wellbores both accurately and quickly. As a result the study may turn aside the necessity of performing well intervention and downhole sensors installation which may significantly reduce well intervention risks and costs.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.