ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

CO₂-brine interfacial tension correlation based on the classical orthogonal polynomials: monovalent salts with common anion

G. Reza Vakili-Nezhaad, Ahmed Al Shaaili, Reza Yousefzadeh, Alireza Kazemi, and Adel Al Ajmi

Department of Petroleum and Chemical Engineering, College of Engineering, Sultan Qaboos University, Muscat, Oman

E-mail: vakili@squ.edu.om

Received: 13 October 2023  Accepted: 9 January 2024

Abstract:

Accurate estimation of CO₂-brine Interfacial Tension (IFT) is of great importance since it is required to model the residual/capillary trapping of CO₂ in geological formations. In this paper, a novel correlation is proposed based on the classical orthogonal polynomials to estimate the CO₂-brine IFT of monovalent salts with common anion. To do so, CO₂-brine IFT samples composed of samples from the literature and experimentally measured values using an in-house high-pressure high-temperature IFT measurement device were collected within a wide range of temperatures, pressures, and salinities. The utilized brines included NaCl and KCl salts. Then, a predictive model was developed based on the Group Method of Data Handling approach as a function of temperature, pressure, and ionic strength. The proposed method was compared with four methods from the literature in terms of average absolute percentage error (AAPE), coefficient of determination \({R}^{2}\), histograms of error, and percent error plots. Results showed the superiority of the proposed method over other methods with an AAPE of 9.85 and \({R}^{2}\) of 0.719. Also, it was shown that the proposed method did not produce too large errors, contrary to other methods. Therefore, the proposed method can be used reliably as a tool for CO₂-brine IFT estimation in CO₂ storage projects.

Keywords: Carbon dioxide; Greenhouse gas; Orthogonal polynomial; CCUS; Brine; IFT

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-024-03321-9

Chemical Papers 78 (6) 3483–3493 (2024)