Title: Analyses of thermal disturbance and formation damages during carbon dioxide injection in shallow and deep reservoirs
Authors: Ilyas Khurshid; Jonggeun Choe
Addresses: University of Modern Sciences, Al Twar-3, 7A Street, Dubai, UAE ' Department of Energy Resources Engineering, Seoul National University, Seoul, 151-744, Korea
Abstract: Understanding the behaviour of CO2 during sequestration activities is very important as its phase and properties may change, affecting CO2 temperature leading to inaccurate temperature prediction. This inaccurate prediction may influence oil recovery and storage activities. In this paper, an analytical solution is presented to estimate CO2 temperature profile in a wellbore, factors affecting it, and formation damages caused due to heated CO2. For this purpose a simulator is developed by solving the proposed analytical solution and using experimentally determined specific heat values of CO2 to predict its temperature accurately. When CO2 enters into a reservoir, it may dissolves into water and changes the pH of the media. Then it reacts with the reservoir rock, leading to rock dissolution in near wellbore region and precipitation in far region. Comparison of our results with the field-measured data gives a good agreement at wide ranges of temperature, depth, and injection rate. The results presented in this study shows that deep oil and gas reservoirs are good candidates for CO2 sequestration than shallow reservoirs. [Received: March 26, 2014; Accepted: March 7, 2015]
Keywords: thermal disturbance; rock dissolution; precipitation; formation damage; heated CO2; carbon dioxide; CO2 injection; shallow reservoirs; deep reservoirs; CO2 sequestration; temperature prediction; oil recovery; oil storage; oil and gas reservoirs; wellbore; simulation; depth; injection rate.
DOI: 10.1504/IJOGCT.2016.074291
International Journal of Oil, Gas and Coal Technology, 2016 Vol.11 No.2, pp.141 - 153
Received: 27 Mar 2014
Accepted: 07 Mar 2015
Published online: 21 Jan 2016 *