Empirical and theoretical analysis of a modified isochronal test in a caspian region gas reservoir

Year 2021, Volume: 5 Issue: 3, 379 - 386, 15.12.2021

Abdullah İşçan

https://doi.org/10.35860/iarej.880198

Abstract

A deliverability test performed in a gas well is one of the fundamental steps to determine the flow potential of the wells in reservoir surveillance. Dynamic reservoir models need robust AOF (Absolute Open Flow), productivity index, permeability for calibration, history matching, and predictions. In this study, a gas well in a Pliocene sandstone gas reservoir was validated using the “Modified Isochronal Testing” method. This study aims to mitigate the efforts done to estimate the phenomenon of flow potential of the gas wells. Hence, the field development activities can be leveraged to a more efficient stage technically and economically. In this study, AOF, Productivity Index (PI), and the permeability of the tested interval were calculated. The validation of the permeability with log and core data increases the confidence level of the work done. AOF is the key performance indicator to define the gas well productivity at zero sand face pressure which is a measure of ranking the production potential of gas wells. The AOF values support the determination of the number of wells to be drilled and the design of the surface facilities. In this study, pressure and time data were obtained and they were analyzed by empirical and theoretical methods. These two methods used in analysis gave very close AOF values; 10.15MMSCF/D (empirical) and10.67 MMSCF/D (theoretical), respectively. The permeability was calculated as 3.42 md, which is in line with the log permeability of 3.70 md and core permeability of 3.40 md.

Keywords

Absolute Open Flow Potential, Gas Well Testing, Modified Iscochronal Test, Reservoir

References

• 1. Brown, K., The Technology of Artificial Lift Methods. 1984, USA: PennWell Publiching Company.
• 2. Lee, J., Well Testing. 1982, USA: SPE AIME.
• 3. Lee, J., Rollins, J.B. and Spivey, J.P., Pressure Transient Testing. 2003, Richardson TX USA: SPE Textbook Series.
• 4. Lee, J. and Wattenberger, R., Gas Reservoir Engineering. 1996, Richardson TX, USA: Henry L. Doherty Memorial Fund of AIME.
• 5. Xi, F., X.Peng, Q. Li, X. Zhao, P. Zhang, and D. Pan, A new method for evaluating the unstable deliverability of gas wells in gas formation testing phase. Natural Gas Industry B, 2020. 7(6): p. 614-623.
• 6. Shoaib,M., D.Viberti, S.B.Eloisa, and F.Verga, Harmonic pulse testing for gas well deliverability Assessment. Geoingegneria Ambientale e Mineraria, 2019. 158(3): p. 53-60.
• 7. Mohamd,I.S. and S.K.,Fatooh,Gas wells deliverability determination using flow after-flow test analysis. Journal of Applied Science, 2020. 4: p.26-43.
• 8. Jiang,L., C.Xiancaho, G. Ping, and Z. Jingchao,Tight carbonate gas well deliverability evaluation and reasonable production proration analysis.J Petrol Explor Prod Technol., 2021. 11: p.2999-3009.
• 9. Sergeev,V.L.,N.T.Phuonget,andA.I.Krainov, Adaptive interpretation of gas well deliverability tests with generating data of the IPR curve. J. Phys.,2017.: Conf. Ser. 803 (012136): p.1-6.
• 10. Aziz, K., Theoretical basis of ısochronal and modified ısochronal back-pressure testing of gas wells. Journal of Canadian Petroleum Technology, 2013. 6(01): p. 20-22.
• 11. Özyuğuran, A., S.Yaman, and Küçükbayrak,S., Prediction of calorific value of biomass based on elemental analysis. International Advanced Researches and Engineering Journal. 2018; 2(3): p. 254-260.
• 12. Hashemi, A., L. Nicolas, and C. Gringarten, Well test analysis of horizontal wells in gas-condensate reservoirs. SPE Res Eval & Eng , 2006. 9(01): p. 86–99, SPE 89905-PA.
• 13. Wu, M., H. Liang, M. Zhang, D. Sun, and P. Zhong, Productivity testing design method of multi-factor control for unconsolidated sandstone gas reservoir. Engineering, 2016. 8(11): p. 815-822.
• 14. Bakyani, A., A. Rasti, S. Qazvini, and F. Esmaeilzadeh, Gas condensate wells simulation to optimize well flow performance using tubing equations coupled with ınflow-performance-relation (IPR) curve. Open Access Library Journal, 2018. 5(5): p. 1-17.
• 15. Igwilo, K., E. Okoro, A. Nwude, A. Mamudu, and C. Onuh, A review on gas well optimization using production performance models:A case study of horizontal well. Open Journal of Yangtze Oil and Gas,2018. 3(1): p. 57-67.
• 16. Meunier,D.F., C.S.Kabir, and M.J. Wittmann, Gas well test analysis: use of normalized pseudovariables. SPE Form Eval, 1987. 2(04): p. 629–636.SPE-13082-PA.
• 17. Soleimani, R.,Y. Jahanpeyma, and M. Salehian, Analysis of horizontal well productivity in tight gas formations and its sensitivity to reservoir properties. J Petrol Explor Prod Technol, September 2019. 9: p. 1237–1244.
• 18. Gomaa, S., A. Attia, A. Abdelhady , S. Khaled, M. Elwageeh, A.N. Elhoshoudy, M. Omran, A. Essam, M.Osama , A. Ashraf, and C. Wagdy, Well testing analysis of unconventional gas reservoirs: real case study of tight gas carbonate reservoir, apollonia formation, western desert, egypt. International Journal of Petroleum and Petrochemical Engineering (IJPPE),2019. 5(1): p. 1-5.
• 19. Brar, G.S. and K. Aziz, Analysis of modified ısochronal tests to predict the stabilized deliverability potential of gas wells without using stabilized flow data. Journal of Petroleum Technology (JPT) ,1978. 30(02): p. 297-304, SPE-6134-PA.
• 20. Sarfraz, A.J. and T. Djebbar, Pressure drawdown and buildup analysis in gas condensate reservoirs. Paper presented at the SPE Western Regional/AAPG Pacific Section Joint Meeting, Anchorage, Alaska, May 2002. SPE-76780-MS.
• 21. Franco, F., A. Rinchon, and M.Useche, Optimized isochronal testing, Society of Petroleum Engineers - Abu Dhabi International Petroleum Exhibition and Conference 2018, ADIPEC 2018.
• 22. Wijayanti, P., L. Said, and P.J. Singh, Analysis of determining deliverability test and ttransient pressure in the PW-02 well of Alpha fields by using Ecrin software. Journal of Physics : Conference Series, 2019. 1402(5): p.1-6.
• 23. Putri,N.A., A. Fattahanisa, A. Ristawati, and R. Setiati, Production capability prediction of a reservoir gas by using gas deliverability analysis to supply gas energy in Indonesia. IOP Conf. Series: Earth and Environmental Science 780. 2021: 012016.
• 24. Iscan, A.G., Water saturation calculation using fractional flow and production logging data in a caspian region sandstone petroleum reservoir. J. Petrol. Sci. Eng. 2021. 200(05): p.108355.
• 25. Iscan, A.G., F.Civan, M.V. Kok, Alteration of permeability by drilling fluid invasion and flow reversal. J. Petrol. Sci. Eng. 2007. 58 (1–2): p.272-244.
• 26. Rawlins, E.L. and Schellhardt, M.A., Backpressure data on natural gas wells and their application to production Practices. 1935 (7). Monograph Series, USBM.
• 27. Houpeurt, A., On the flow of gases in porous media. Revue de L’ Institut Francais du Petrole, 1959. 15(11): p. 1468-1684.
• 28. Donohue, D. and Ertrekin, T., Gas Well Testing Theory, Practice & Regulation. 1982, Springer Netherlands.
• 29. Ikoku, C.U., Natural Gas Production Engineering. 1992, Krieger Publishing Company.
• 30. Chaudry, A., Gas Well Testing Handbook 2003, Elsevier and Gulf Pulishing.