Salinity-Based Pump-and-Dump Strategy for Drilling Salt With Supersaturated Fluids
- Thomas J. Akers (ExxonMobil Development Company)
- Document ID
- Society of Petroleum Engineers
- SPE Drilling & Completion
- Publication Date
- March 2011
- Document Type
- Journal Paper
- 151 - 159
- 2011. Society of Petroleum Engineers
- 1.1.6 Hole Openers & Under-reamers, 1.14 Casing and Cementing, 1.6 Drilling Operations, 1.11 Drilling Fluids and Materials
- riserless, salt, supersaturated, deepwater, pump and dump
- 1 in the last 30 days
- 834 since 2007
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Riserless drilling with weighted-drilling-fluid systems, commonly referred to as a "pump-and-dump" drilling strategy, is an established drilling technique used on deepwater wells with shallow hazards. Large holes and high flow rates result in very large volumes of fluid being required to drill to total depth (TD), circulate the well clean, and cement the conductor-casing string. Fluids management becomes a major issue in the riserless hole section. In the Gulf of Mexico, mud is often densified in excess of well requirements and then blended with seawater in a "cut-back" operation to reach the desired density to pump downhole.
When performing riserless drilling into salt, a pump-and-dump strategy is often used. Dilution with seawater, however, results in an undersaturated fluid. This fluid leaches the salt, resulting in substantial hole enlargement. The hole enlargement can result in poor cementing jobs that require remediation or even an additional string of casing. A unique operation has been employed in the Santos basin of Brazil where a supersaturated-brine fluid was used to conduct a pump-and-dump operation with the goal of drilling with a saturated-brine fluid and minimizing hole enlargement. This paper details the planning of the operation, fluid design, and pilot testing. Fluids management, equipment rig up, and results are discussed in detail. The operation has been executed successfully twice, with both operations achieving the set objectives for the wells. Unforeseen complications that were encountered are discussed along with lessons learned that have been applied to subsequent operations.
|File Size||1023 KB||Number of Pages||9|
Alberty, M.W., Hafle, M.E., Mingle, J.C., and Byrd, T.M. 1999. Mechanisms of Shallow Waterflows andDrilling Practices for Intervention. SPE Drill & Compl 14 (2): 123-129. SPE-56868-PA. doi: 10.2118/56868-PA.
Barker, J.W., Feland, K.W., and Tsao, Y-H. 1994. Drilling Long Salt Sections Along theU.S. Gulf Coast. SPE Drill & Compl 9 (3): 185-188.SPE-24605-PA. doi: 10.2118/24605-PA.
Durie, R.W. and Jessen, F.W. 1964a. Mechanism of the Dissolution of Salt inthe Formation of Underground Salt Cavities. SPE J. 4(2): 183-190; Trans., AIME, 231. SPE-678-PA. doi:10.2118/678-PA.
Durie, R.W. and Jessen, F.W. 1964b. The Influence of Surface Features inthe Salt Dissolution Process. SPE J. 4 (3): 275-281;Trans., AIME, 231. SPE-1005-PA. doi: 10.2118/1005-PA.
Johnson, M. and Rowden, M. 2001. Riserless Drilling Technique SavesTime and Money by Reducing Logistics and Maximizing Borehole Stability.Paper SPE 71752 presented at the SPE Annual Technical Conference andExhibition, New Orleans, 30 September-3 October. doi: 10.2118/71752-MS.
Kazemi, H. and Jessen, F.W. 1964. Mechanism of Flow and ControlledDissolution of Salt in Solution Mining. SPE J. 4 (4):317-329; Trans., AIME, 231. SPE-1007-PA. doi:10.2118/1007-PA.
Poiate, E. Jr., Costa, A.M., and Falcao, J.L. 2006. Well Design for Drilling ThroughThick Evaporite Layers in Santos Basin--Brazil. Paper SPE 99161 presentedat the IADC/SPE Drilling Conference, Miami, Florida, USA, 21-23 February. doi:10.2118/99161-MS.
Rohleder, S.A., Sanders, W.W., Williamson, R.N., Faul, G.L., and Dooley,L.B. 2003. Challenges of Drillingan Ultra-Deep Well in Deepwater-Spa Prospect. Paper SPE 79810 presented atthe SPE/IADC Drilling Conference, Amsterdam, 19-21 February. doi:10.2118/79810-MS.
Roller, P.R., Magner, M.D., and Drury, R. 2001. Using Conventional and Unique Methodsto Drill a Technically Demanding Shallow Flow Zone. Paper SPE 67773presented at the SPE/IADC Drilling Conference, Amsterdam, 27 February-1 March.doi: 10.2118/67773-MS.
Schuberth, P.C. and Walker, M.W. 2000. Shallow Water Flow Planning andOperations: Titan No.1 Exploration Well, Deepwater Gulf of Mexico. SPEDrill & Compl 15 (4): 234-240. SPE-65751-PA. doi:10.2118/65751-PA.
Turner, K.M. and Morales, L.J. 2000. Riserless Drilling With CaCl2 MudPrevents Shallow Water Flows. Paper SPE 59172 presented at the IADC/SPEDrilling Conference, New Orleans, 23-25 February. doi: 10.2118/59172-MS.
Whitfill, D., Rachal, G., Lawson, G., and Armagost, K. 2002. Drilling Salt--Effect of DrillingFluid on Penetration Rate and Hole Size. Paper SPE 74546 presented at theIADC/SPE Drilling Conference, Dallas, 26-28 February. doi:10.2118/74546-MS.
Whitson, C.D. and McFadyen, M.K. 2001. Lessons Learned in the Planning andDrilling of Deep, Subsalt Wells in the Deepwater Gulf of Mexico. Paper SPE71363 presented at the SPE Annual Technical Conference and Exhibition, NewOrleans, 30 September-3 October. doi: 10.2118/71363-MS.
Willson, S.M., Driscoll, P.M., Judzis, A., Black, A.D., Martin, J.W.,Ehgartner, B.L., and Hinkebein, T.E. 2004. Drilling Salt Formations WithSeawater Can Significantly Reduce Well Costs. SPE Drill & Compl 19 (3): 147-155. SPE-87216-PA. doi: 10.2118/87216-PA.