Abstract

Gas condensate is commonly located in the deep strata under High Temperature High Pressure (HTHP) conditions, which is mainly composed of methane and derived its high molecular weight from the quantity of plus fractions (C_n+). Thus, in order to accurately predict the volumetric behavior for gas condensate, the selection of suitable characterization methods for the C_n+ is of key importance. The compressibility factor as an essential volumetric parameter is often used to analyze the PVT behavior in gas condensate engineering. In this study, four empirical correlations for plus fraction characterization are evaluated and then a new combination method is presented to determine the compressibility factor for gas condensate under HTHP conditions.

Keywords:

Compressibility factor, characterization method, gas condensate, HTHP condition, plus fraction,

References

1. Bang, V.S.S. and G.A. Pope, 2010. Phase-behavior study of hydrocarbon/water/methanol mixtures at reservoir conditions. SPE J., 15(4): 958-968.
   CrossRef    
2. Chang Yu, S., L. Huang, Y. Ke-Le, M. Qing-Lan, L. Bei and C. Guang-Jin, 2012. Experiments and modeling of volumetric properties and phase behavior for condensate gas under ultra-high-pressure conditions. Ind. Eng. Chem. Res., 51(19): 6916-6925.
   CrossRef    
3. Canas Marin, W.A., J.D. Ortiz-Arango, U.E. Guerrero-Aconcha and C.P. Soto-Tavera, 2007. Thermodynamic derivative properties and densities for hyperbaric gas condensates: SRK equation of state predictions versus Monte Carlo data. Fluid Phase Equilibr., 253(2): 147-154.
   CrossRef    
4. Dranchk, P.M., R.A. Purvis and D.B. Robinson, 1974. Computer Calculation of Natural Gas Compressibility Factors Using the Standing and Katz Correlation. Institute of Petroleum Technical Series, No. IP74-008, pp: 1-13.
   
5. Elsharkawy, A.M. and A. Elkamel, 2000. Compressibility factor for sour gas reservoirs. Proceeding of the SPE Asia Pacific Oil and Gas Conference and Exhibition. Brisbane, Australia, pp: 1-12.
   CrossRef    
6. Elsharkawy, A.M., 2004. Efficient methods for calculations of compressibility, density and viscosity of natural gases. Fluid Phase Equilibr., 218(1): 1-13.
   CrossRef    
7. El-Sharkawy, I., S. Sherif, I. Mila, M. Bouzayen and S. Jayasankar, 2009. Molecular characterization of seven genes encoding ethylene-responsive transcriptional factors during plum fruit development and ripening. J. Exp. Bot., 60(3): 907-922.
   CrossRef    PMid:19213809 PMCid:PMC2652048    
8. Fort, J., 2000. The Elgin/Franklin project: Developing the largest high pressure/high temperature fields in the world. Proceeding of the Offshore Technology Conference. Houston, Texas.
   CrossRef    
9. Kesler, M.G. and B.I. Lee, 1976. Improve prediction of enthalpy fractions. Hydrocarb. Process., 55(3): 153-158.
   
10. Neuhaus, D., G. Browning and O. Estensen, 1999. Managing seismic positioning uncertainty in HPHT developments. Proceeding of the Offshore Europe Oil and Gas Exhibition and Conference. Aberdeen, United Kingdom.
    CrossRef    
11. Stewart, W.F., S.F. Burkhard and D. Voo, 1959. Prediction of pseudo critical parameters for mixtures. Proceeding of the Paper Presented at the AICHE Meeting. Kansas City, MO.
    
12. Sutton, R.P., 1985. Compressibility factors for high-molecular-weight reservoir gases. Proceeding of the SPE Annual Technical Conference and Exhibition. Las Vegas, Nevada, pp: 22-25.
    CrossRef    
13. Ungerer, P., B. Faissat, C. Leibovici, H. Zhou, E. Behar, G. Moracchini and J.P. Courcy, 1995. High pressure-high temperature reservoir fluids: Investigation of synthetic condensate gases containing a solid hydrocarbon. Fluid Phase Equilibr., 111(2): 287-311.
    CrossRef    
14. Whitson, C.H. and S.B. Torp, 1983. Evaluating constant-volume depletion data. J. Petrol. Technol., 35(3): 610-620.
    CrossRef    
15. Wichert, E. and K. Aziz, 1972. Calculation of Z's for sour gases. Hydrocarb. Process., 51(5): 119-122.
    
16. Xu Qiang, G., Y. Wei, C. Shuang and G. Tian Min, 2000. Comparison of methods for calculating compressibility factor of natural gas at elevated high pressure. J. Univ., Petrol. China, 24(6): 36-38.
    
17. Yarborough, L. and K.R. Hall, 1974. How to solve equation of state for Z-factor. Oil Gas J., 72(7): 86-92.
    
18. Yi Cun, C. and Y. Bao Xin, 2001. Geochemical condition of gas condensate reservoir in Tarim. XinJiang Petrol. Geol., 22(5): 414-416.
    

Competing interests

The authors have no competing interests.

Open Access Policy

This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

Copyright

The authors have no competing interests.