Table of Contents
Journal of Thermodynamics
Volume 2010 (2010), Article ID 142475, 9 pages
Research Article

Prediction of Molar Volumes of the Sudanese Reservoir Fluids

1Department of Chemical Engineering, University of Khartoum, P.O. Box 321, Khartoum, Sudan
2Department of Petroleum Transportation & Refining Engineering, College of Petroleum Engineering and Technology, Sudan University of Science and Technology, P.O. Box 566, Khartoum, Sudan

Received 2 October 2009; Revised 16 February 2010; Accepted 21 February 2010

Academic Editor: Perla B. Balbuena

Copyright © 2010 A. A. Rabah and S. A. Mohamed. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


This paper provided important experimental PVT data of the Sudanese reservoir fluids. It includes composition analysis of 11 mixtures and about 148 PVT data points of constant mass expansion (CME) tests at pressures below the bubble point. The datasets are compared with eight equations of state (EOS), namely, Peng Robinson (PR), Soave-Redlich-Kwong (SRK), Lawal-Lake-Silberberg (LLS), Adachi-Lu-Sugie (ALS), Schmidt-Wenzel (SW), Patel-Teja (PT), Modified-Nasrifar-Moshfeghian (MNM), and Harmens-Knapp (HK). The results of comparison reveals that, with the exception of PR and ALS EOSs, all other EOSs yield consistently a higher average absolute percent deviation (AAPD) in the prediction of molar volume; it exceeds 20% by all mixtures. The grand average AAPD of all mixtures is 17 and 16 for PR and ALS, respectively. ALS is selected to represents the mixtures. It is modified by replacing the coefficient (b1) of the parameter (b1) in the dominator of repulsive term by that of PR. This procedure enhanced the accuracy of ALS by 30 to 90% for individual mixtures and the grand average AAPD is significantly reduced from 16 to about 7.