Tunnel-Length Modeling for Coiled-Tubing-Acid-Tunneling Stimulation in Carbonate Reservoirs
- Silviu Livescu (Baker Hughes) | Steven Craig (Baker Hughes) | Bill Aitken (Baker Hughes)
- Document ID
- Society of Petroleum Engineers
- SPE Production & Operations
- Publication Date
- February 2019
- Document Type
- Journal Paper
- 159 - 169
- 2019.Society of Petroleum Engineers
- coiled tubing, modeling, acid tunneling, telemetry
- 0 in the last 30 days
- 166 since 2007
- Show more detail
- View rights & permissions
|SPE Member Price:||USD 5.00|
|SPE Non-Member Price:||USD 35.00|
A coiled-tubing (CT)-acid-tunneling-stimulation technique has been successfully applied in the preceding 15 years on limestone and dolomite reservoirs around the world (the Middle East, southeast Asia, North America, South America, and Europe). Several case histories were presented in the past showing that this technique might bring significant benefits over other carbonate-stimulation methods in openhole wells. In this paper, the parameters affecting the predicted and achieved tunnel lengths are discussed for the first time. The acid-tunneling technique consists of pumping hydrochloric acid (HCl) through conventional CT and a bottomhole assembly (BHA) with jetting nozzles to create (without drilling) stable drainage holes (tunnels) into the reservoir pay zone. The BHA also includes a special kickoff tool, with two pressure-activated bending joints, that controls the tunnel-creation direction. The acid that is not consumed during the main tunneling process leaks into the reservoir rock, creating wormholes that improve the connectivity between the reservoir and the wellbore and positively influence well production. This acid-tunneling technique can potentially create numerous tunnels with different depths. The optimization of the tunnel-creation-depth selection is made by production-software simulation using such critical information as the well parameters (trajectory and size), available logs (image, resistivity, caliper, drilling), and past reservoir information.
The results from many field case histories involving the CT acid-tunneling technique from around the world were presented previously. However, many questions remain unanswered regarding the actual downhole tunnel-initiation/creation process. In this study, a detailed discussion of acid-tunneling modeling is included to answer some of those questions. The parameters affecting the predicted tunnel lengths and the parameters that could be monitored or adjusted to create the tunnels smoothly are discussed. This paper describes the CT acid-tunneling technology and discusses some of the most important questions regarding downhole CT acid-tunneling creation. The acid-tunneling-technique performance and benefits confirmed during field operations are presented.
|File Size||542 KB||Number of Pages||11|
Aitken, W. A. H., Livescu, S., and Craig, S. 2018. 30 Years of Continuous Coiled Tubing Modeling Software Development and Applications Creating New Capabilities. Presented at the SPE/ICoTA Coiled Tubing and Well Intervention Conference and Exhibition, The Woodlands, Texas, 27–28 March. SPE-189935-MS. https://doi.org/10.2118/189935-MS.
Beckham, R. E., Shuchart, C. E., and Buechler, S. R. 2015. Impact of Acid Jetting on Carbonate Stimulation. Presented at the International Petroleum Technology Conference, Doha, Qatar, 6–9 December. IPTC-18360-MS. https://doi.org/10.2523/IPTC-18360-MS.
Blanco, D., Sach, M., and Livescu, S. 2017. 3 1/2-in. Coiled Tubing Telemetry System Saves Time and Improves Operational Efficiency During a Multi-Well Campaign in Norway. Presented at the SPE/ICoTA Coiled Tubing and Well Intervention Conference and Exhibition, Houston, 21–22 March. SPE-184754-MS. https://doi.org/10.2118/184754-MS.
Correa, P., Parra, D., Craig, S. et al. 2018. Operational Improvements Using a Coiled Tubing Telemetry System for a Complex Milling Operation in Shut-In Conditions. Presented at the SPE/ICoTA Coiled Tubing and Well Intervention Conference and Exhibition, The Woodlands, Texas, 27–28 March. SPE-189910-MS. https://doi.org/10.2118/189910-MS.
Craig, S., Aitken, B., and Livescu, S. 2017. Enhancing Well Interventions With the Use of Transient Software—New Case Histories From Around the World. Presented at the Abu Dhabi International Petroleum Exhibition and Conference, Abu Dhabi, 13–16 November. SPE-188561-MS. https://doi.org/10.2118/188561-MS.
Diaz, J. D., Espina, V., Guerrero, M. et al. 2007. Successful Implementation of Coiled-Tubing Acid Tunneling Gives Operator a Viable Alternative to Conventional Stimulation Techniques in Carbonate Reservoirs. Presented at the SPE/ICoTA Coiled Tubing and Well Intervention Conference and Exhibition, The Woodlands, Texas, 20–21 March. SPE-107084-MS. https://doi.org/10.2118/107084-MS.
Guimaraes, Z., Duque, L. H., Almeida, V. et al. 2011. Construction Project for the First Dendritic Well Offshore in Brazil. Presented at Brasil Offshore, Macae´, Brazil, 14–17 June. SPE-143081-MS. https://doi.org/10.2118/143081-MS.
Livescu, S. and Watkins, T. 2014. Water Hammer Modelling in Extended Reach Wells. Presented at the SPE/ICoTA Well Intervention and Coiled Tubing Conference and Exhibition, The Woodlands, Texas, USA, 25–26 March. SPE-168297-MS. http://dx.doi.org/10.2118/168297-MS.
Livescu, S. and Aitken, W. A. H. 2015. Energy Industry Operation Prediction and Analysis Based on Downhole Conditions. US Patent No. 20,160,314,420 A1.
Livescu, S., Blanco, D. A., Vacik, L. et al. 2015. Novel 2 7/8-in. Real-Time Downhole Data Monitoring System for Coiled Tubing Operations. Presented at the SPE Annual Technical Conference and Exhibition, Houston, 28–30 September. SPE-174850-MS. https://doi.org/10.2118/174850-MS.
Livescu, S. and Craig, S. 2017. A Critical Review of the Coiled Tubing Friction-Reducing Technologies in Extended-Reach Wells. Part 1: Lubricants. J. Pet. Sci. Eng. 157 (August): 747–759. https://doi.org/10.1016/j.petrol.2017.07.072.
Livescu, S. and Watkins, T. 2017. Real Time Steerable Acid Tunneling System. US Patent No. 9,850,714.
Livescu, S., Craig, S. H., and Aitken, B. 2017. Fluid-Hammer Effects on Coiled-Tubing Friction in Extended-Reach Wells. SPE J. 22 (1): 365–373. SPE-179100-PA. https://doi.org/10.2118/179100-PA.
Livescu, S. and Craig, S. 2018. A Critical Review of the Coiled Tubing Friction-Reducing Technologies in Extended-Reach Wells. Part 2: Vibratory Tools and Tractors. J. Pet. Sci. Eng. 166 (July): 44–54. https://doi.org/10.1016/j.petrol.2018.03.026.
Livescu, S., Watkins, T., and Najafov, J. 2018. Ten Years of Continuous Technology Development and Field Application of a Coiled-Tubing Tube-Wire Telemetry System: Past, Present and Future. SPE Prod & Oper. SPE-187374-PA (in press; posted 17 August 2018). https://doi.org/10.2118/187374-PA.
Misselbrook, J., Wilde, G., and Falk, K. 1991. The Development and Use of a Coiled-Tubing Simulation for Horizontal Applications. Presented at the SPE Annual Technical Conference and Exhibition, Dallas, 6–9 October. SPE-22822-MS. https://doi.org/10.2118/22822-MS.
Misselbrook, J. G., Crabtree, A. R., and Portman, L. N. 2012. Acid Tunneling Bottom Hole Assembly and Method Utilizing Reversible Elbow Joints. US Patent No. 8,205,672 B2.
Moss, P. J., Portman, L. N., Rae, P. J. et al. 2006. Nature Had It Right After All! Constructing a “Plant Root”-Like Drainage System With Multiple Branches and Uninhibited Communication With Pores and Natural Fractures. Presented at the SPE Annual Technical Conference and Exhibition, San Antonio, Texas, 24–27 September. SPE-103333-MS. https://doi.org/10.2118/103333-MS.
Ndonhong, V., Belostrino, E., Zhu, D. et al. 2017. Acid Jetting in Carbonate Rocks: An Experimental Study. SPE Prod & Oper 33 (2): 382–392. SPE-180113-PA. https://doi.org/10.2118/180113-PA.
Perex, L. A. A., Diaz, J. D., Navarro, M. et al. 2008. Successful Offshore Application of Acid Tunneling Technology: Overcoming the Difficulties of High Depths, Temperatures, and Deviations. Presented at the SPE/ICoTA Coiled Tubing and Well Intervention Conference and Exhibition, The Woodlands, Texas, 1–2 April. SPE-113855-MS. https://doi.org/10.2118/113855-MS.
Portman, L. N., Rae, P. J., and Munir, A. 2002. Full-Scale Tests Prove It Practical To “Drill” Holes With Coiled Tubing Using Only Acid; No Motors, No Bits. Presented at the SPE/ICoTA Coiled Tubing Conference and Exhibition, Houston, 9–10 April. SPE-74824-MS. https://doi.org/10.2118/74824-MS.
Press, W. H., Teukolsky, S. A., Vetterling, W. T. et al. 1992. Numerical Recipes in C, second edition. New York City: Cambridge University Press.
Rae, P. and Di Lullo, G. 2001. Chemically-Enhanced Drilling With Coiled Tubing in Carbonate Reservoirs. Presented at the SPE/ICoTA Coiled Tubing Roundtable, Houston, 7–8 March. SPE-68439-MS. https://doi.org/10.2118/68439-MS.
Rae, P. J., Portman, L. N., and DiLullo, G. 2007. The Dendritic Well—A Simple Process Creates an Ideal Reservoir Drainage System. Presented at the European Formation Damage Conference, Scheveningen, The Netherlands, 30 May–1 June. SPE-108023-MS. https://doi.org/10.2118/108023-MS.
Ramondenc, P. and Baez, F. 2013. Using Fiber-Optic-Enabled Coiled Tubing To Quantify Fluid Placement and Optimize Stimulation Effectiveness During Matrix Stimulation Treatments in Carbonate Reservoirs. Presented at the SPE European Formation Damage Conference and Exhibition, Noordwijk, The Netherlands, 5–7 June. SPE-165121-MS. https://doi.org/10.2118/165121-MS.
Ridner, D., Frick, T., Zhu, D. et al. 2018. Influence of Transport Conditions on Optimal Injection Rate for Acid Jetting in Carbonate Reservoirs. Presented at the SPE International Conference and Exhibition on Formation Control, Lafayette, Louisiana, 7–9 February. SPE-189546-MS. https://doi.org/10.2118/189546-MS.
Seagraves, A. N., Smart, M. E., and Ziauddin, M. E. 2018. Fundamental Wormhole Characteristics in Acid Stimulation of Perforated Carbonates. Presented at the SPE International Conference and Exhibition on Formation Control, Lafayette, Louisiana, 7–9 February. SPE-189506-MS. https://doi.org/10.2118/189506-MS.
Stanley, R., Portman, L. N., Diaz, J. D. et al. 2010. Global Application of Coiled-Tubing Acid Tunneling Yields Effective Carbonate Stimulation. Presented at the SPE Annual Technical Conference and Exhibition, Florence, Italy, 19–22 September. SPE-135604-MS. https://doi.org/10.2118/135604-MS.
Wehunt, C. D., Lattimer, S. K. K., and McDuff, D. R. 2018. Dendritic Acidizing: The Light at the End of the Tunnel. Presented at the SPE/ICoTA Coiled Tubing and Well Intervention Conference and Exhibition, The Woodlands, Texas, 27–28 March. SPE-189945-MS. https://doi.org/10.2118/189945-MS.