Interference of Sodium Chloride on Shale Stabilization with Potassium Chloride in Drilling Fluid

Document Type : Research Paper


1 Department of Chemistry, Omidiyeh Branch, Islamic Azad University, Omidiyeh, Iran

2 Department of Petroleum Engineering, Omidiyeh Branch, Islamic Azad University, Omidiyeh, Iran


 The shale formation drilling often generates a wide range of problems if ordinary water-based muds are employed. Furthermore, the alteration of shale formation has complicated the development of adequate drilling fluids. The con­trol of shale instability by the exchange of potassium cations with shale structure is well accepted in the drilling fluid industry. In the cases where seawater or brackish water is used as a base, the presence of Na+ and Cl- in the drilling fluid can disrupt the shale cation exchange process. In this study, KCl fluids with concentrations of 1 to 15 wt% were prepared and analyzed with linear swelling, capillary suction time, and dispersion experiments on shale inhibition property, and then NaCl was added to potassium fluids at different concentrations. The different result of mixed salt fluid and KCl fluids indicated that the presence of sodium chloride could affect the potassium yield in the drilling fluid. Moreover, the low concentration of NaCl/KCl showed better results for shale inhibition, although the increase in NaCl concentration caused high swelling and decreased KCl efficiency in drilling fluid. Ultimately, it was found that the addition of 1 – 5wt% NaCl to 3 – 5wt% KCl was preferable to stabilizing old shale formation. But to drill active and young shale formation, the use of KCl alone in the liquid was recommended.


Gholami R, Elochukwua H, Fakharib N, Sarmadivaleh M (2018) A review of ‎borehole instability in active shale formations: Interactions, mechanisms, and ‎inhibitors‎, Earth-Science Reviews, 177, 2–13. ##
Charlez P A, Heugas O (1991) Evaluation of Optimal Mud Weight in Soft Shale ‎Levels‎, in 32nd US Symposium Rock Mechanics as a ‎Multidisciplinary Science, American Rock Mechanics Association, January. ##
Chen X, Tan C T, Detourna C (2002) the impact of mud filtration on wellbore ‎stability fracture rock masses, in SPE/ISRM 7824. Rock ‎Mechanics Conference, Texas‎. ##
Behnamanhar H, Noorbakhsh S, Maghsoudloo J (2014) Environmentally Friendly Water-‎Based Drilling Fluid for Drilling of Water-Sensitive Formations‎, Journal of Petroleum ‎and Gas Exploration Research, 4(4): 60-71. ##
Hanyi Z, Zhengsong Q, Binqiang X, Weiji W (2013) Bis(hexamethylene) triamine as ‎potential shale inhibitor in water-Ba§sed drilling fluid‎, Petroleum Engineering ‎Journal, 6: 49-56. ##
Hua-Rui H, Cheng-hu X, Gang C, Jing-Rui Z, Hong L (2015) Synthesis and ‎evaluation of carboxymethyl glucoside as montmorillonite swelling inhibitor‎, ‎Petroleum Engineering Journal, 8: 198-202. ##
Kaihe L, Hanyi Z, Guanlong R, Yuxia L (2014) Properties evaluation and application ‎of organic amine inhibitor on the properties of drilling fluids‎, Petroleum Engineering ‎Journal, 7: 50-54. ##
Chenevert M E, Pernot V (1998) Control of shale swelling pressures using ‎inhibitive water based muds‎, in SPEAnnual Technical ‎Conference and Exhibition, New Orleans, September, 27-30. ##
Kersten G V (1946) Results and use of oil-base fluids in drilling and completing wells, in Spring Meeting of the Pacific Coast District, Division of Production, Los Angeles. ##
Browning W C, Perricone A C (1963) Clay chemistry and drilling fluids, in First University of Texas Conference on Drilling and Rock Mechanics, Austin, January. ##
Van Oort E (2003) On the physical and chemical stability of shales‎, Journal of ‎Petroleum Science and Engineering, 38: 213–235.  ##
O’Brien, Chenevert M E (1973) Stabilizing sensitive shales with inhibited, ‎potassium-based drilling fluids‎,JPT, 25: 1089-1100. ##
Steiger R P, Leung P K (1992) Quantitative determination of the nechanical properties ‎of shales‎, in SPE Drilling Engineering, September, 7(03): 181-185. ##
Naeimavi M, Khazali F, Abdideh M and Saadati Z (2019) Potassium sorbate ‎as substitute for KCl to shale ‎inhibition in water-base drilling fluids, Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 1-15. ##
Clark R, (1976) Polyacrylamide/potassium-‎chloride mud for drilling water-sensitive shales‎, Journal of Petroleum Technology, 28(6): 719-727. ##
Van Oort E (1997) Physico-chemical stabilization of shales, in International Symposium on Oilfield Chemistry, In SPE 00037263, Houston Texas USA. ##
Caenn R, Darley H C H, Gray G R (2011) Composition and properties of drilling ‎and completion fluids‎ (6th ed.) Chapter 5, Gulf professional publishing USA 180-205. ##
Gray G R, Darley H C H, Rogers W F (1980) Composition and Properties of Oil Well ‎Drilling Fluids (4th ed.), Houston: Gulf Publication 1-693. ##
Levine I N (2009) Physical Chemistry (6th ed.) Mcgraw-hill companies, New York USA 2: 1-967. ##
Gomez S L, He W (2012) ‎Fighting wellbore instability: customizing drilling fluids based on laboratory studies of ‎shale-fluid interactions, in SPE Asia Pacific Drilling Technology ‎Conference and Exhibition Tianjin China.
Flowers P (2015) Chemistry Houston Texas: OpenStax 603. ##
OFITE (2014) OFI Testing Equipment Inc Internet: ##
Pagels M, Hinkel J J, Willberg D M (2012) Moving beyond the capillary suction time test, Presented at the SPE International Symposium and Exhibition on ‎Formation Damage Control Lafayette Louisiana USA February 15-17. ##
Friedheim J, Guo Y S, Gomez S (2011) Testing and evaluaution techniques for drilling fluids-shale interaction and shale stability. In 45th US Rock Mechanics/Geomechanics Symposium, American Rock Mechanics Association January 11-502. ##
Van Oort E (2003) On the physical and chemical stability of shales. Journal of Petroleum ‎Science and Engineering, 38, 213–235. ##
Karaborni S, Smit B, Heidug W K, Urai J L, van Oort E (1996) The swelling of clays: molecular simulations of the hydration of montmorillonite. Science February 1102. ##
API, ANSI RECOMMENDED PRACTICE 13B-1, Recommended Practice for Field ‎Testing Water-based Drilling Fluids (4th ed.)‎ API, 2009. ##
Bol G M (1986) The effect of various polymers and salts on borehole and cutting stability in ‎water-base shale drilling fluids, SPE/IADC Drilling Conference Society of Petroleum Engineers January. ##
Clark R K, Scheuerman R F, Rath H (1976) Polyacrylamide/potassium-‎chloride mud for drilling water-sensitive shales, Journal of Petroleum Technology 28(6): 719-727. ##
Roehl E A Hackett J L (1982) A laboratory technique for screening shale inhibitors. in 57th Annual Fall Meet, New Orleans Louisiana January. ##
Steiger R P (1982) Fundamentals and use of potassium/polymer drilling fluids to minimize ‎drilling and completion problems associated with hydrateable clays. Journal of Petroleum Technology August 34(08): 1-661. ##
Wingrave J A, Kubena E J R, Dootv C F. Whitfill D L, Cords D P (1987) New chemical ‎package produces an improved shale inhibitive water based drilling fluid system. in 45th Annual ‎Fall Meet, Society of Petroleum Engineers, Dallas, Texas, January. ##
Chenevert M E, Osisanya S (1989) Shale/mud inhibition defined with rig-‎site methods‎, in SPE Drilling Engineering, September 4(3): 261-268. ##