IP Library › Granted Patent US 12,552,981
Granted Patent B2
US 12,552,981 · App. 18/734,267 · Granted Feb 17, 2026

Filter cake removal treatment fluid with chelating agent and viscoelastic surfactant

Inventors: Rajesh Kumar Saini (Cypress, TX); Katherine Leigh Hull (Houston, TX); Amy J. Cairns (Houston, TX); Brady Kevin Crane (Houston, TX)
Assignee: Saudi Arabian Oil Company
C09K8/528C09K8/34C09K8/536E21B37/06C09K2208/30
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Quick Facts
Patent No.
US 12,552,981
App. No.
18/734,267
Granted
Feb 17, 2026
Kind
B2
Abstract

A reactive treatment fluid for filter cake removal, the reactive treatment fluid including: a base fluid; a chelating agent; a carbonate; an oxidizing salt; an organic acid; a viscoelastic surfactant (VES); and a base.

Claims (42)

1 . A reactive treatment fluid for filter cake removal, the reactive treatment fluid comprising:

a base fluid that is from about 50 weight percent (wt. %) to about 70 wt. % of the reactive treatment fluid;

a chelating agent that is from about 1 wt. % to about 15 wt. % of the reactive treatment fluid;

a carbonate that is from about 5 wt. % to about 30 wt. % of the reactive treatment fluid;

an oxidizing salt that is from about 1 wt. % to about 20 wt. % of the reactive treatment fluid;

an organic acid that is from about 1 wt. % to about 15 wt. % of the reactive treatment fluid;

a viscoelastic surfactant (VES); and

a base that is from about 0.2 wt. % to about 5 wt. % of the reactive treatment fluid.

2 . The reactive treatment fluid of claim 1 , wherein the base fluid is water.

3 . The reactive treatment fluid of claim 1 , wherein the chelating agent comprises an aminopolycarboxylic acid or a salt thereof.

4 . The reactive treatment fluid of claim 1 , wherein the chelating agent comprises diethylenetriamine pentaacetic acid (DTPA), hydroxyethyl ethylenediaminetriacetic acid (HEDTA), ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), ethyleneglycol-O,O′-bis(2-aminoethyl)-N,N,N′,N′-tetraacetic acid (EGTA), hydroxyethyl iminodiacetic acid (HIDA), glutamic acid N,N-diacetic acid (GLDA), or a salt thereof.

5 . The reactive treatment fluid of claim 1 , wherein the carbonate is potassium carbonate or cesium carbonate.

6 . The reactive treatment fluid of claim 1 , wherein the oxidizing salt comprises a chlorate or bromate.

7 . The reactive treatment fluid of claim 1 , wherein the organic acid comprises oxalic acid, formic acid, acetic acid, or lactic acid.

8 . The reactive treatment fluid of claim 1 , wherein the VES comprises erucylamidopropyl betaine.

9 . The reactive treatment fluid of claim 1 , wherein the base comprises potassium hydroxide.

10 . The reactive treatment fluid of claim 1 , further comprising an acid-generating material.

11 . The reactive treatment fluid of claim 10 , wherein the acid-generating material comprises polylactic acid (PLA), polyglycolic acid (PGA), an orthoester, or a polyanhydride.

12 . A reactive treatment fluid for filter cake removal, the reactive treatment fluid comprising:

water that is from about 50 weight percent (wt. %) to about 70 wt. % of the reactive treatment fluid;

diethylenetriamine pentaacetic acid (DTPA) that is from about 1 wt. % to about 15 wt. % of the reactive treatment fluid;

a carbonate that is from 5 wt. % to 30 wt. % of the reactive treatment fluid;

an oxidizing salt that is from about 1 wt. % to about 20 wt. % of the reactive treatment fluid;

oxalic acid that is from about 1 wt. % to about 15 wt. % of the reactive treatment fluid;

a viscoelastic surfactant (VES); and

a base that is from about 0.2 wt. % to about 5 wt. % of the reactive treatment fluid.

13 . The reactive treatment fluid of claim 12 , wherein a pH of the reactive treatment fluid is from about 9 to about 12.

14 . A method of treating a wellbore for filter cake removal, the method comprising:

injecting a reactive treatment fluid into a wellbore in a subterranean formation comprising a filter cake on a wall of the wellbore, the filter cake comprising a barite, the reactive treatment fluid comprising:

a base fluid that is from about 50 weight percent (wt. %) to about 70 wt. % of the reactive treatment fluid,

a chelating agent that is from about 1 wt. % to about 15 wt. % of the reactive treatment fluid,

a carbonate that is from about 5 wt. % to about 30 wt. % of the reactive treatment fluid,

an oxidizing salt that is from about 1 wt. % to about 20 wt. % of the reactive treatment fluid,

an organic acid that is from about 1 wt. % to about 15 wt. % of the reactive treatment fluid,

a viscoelastic surfactant (VES), and

a base that is from about 0.2 wt. % to about 5 wt. % of the reactive treatment fluid;

contacting the reactive treatment fluid with the filter cake in the wellbore, the reactive treatment fluid dissolving or exfoliating the barite from the wall into the reactive treatment fluid; and

recovering the reactive treatment fluid comprising the barite removed from the wall.

15 . The method of claim 14 , further comprising, prior to injecting the reactive treatment fluid into the wellbore, forming the wellbore by drilling, wherein the drilling forms the filter cake in the wellbore.

16 . The method of claim 15 , wherein the drilling comprises drilling using an oil-based drilling fluid (OBDF) comprising an oil, a polymer, and the barite.

17 . The method of claim 14 , further comprising providing carbon dioxide (CO 2 ) into the wellbore.

18 . The method of claim 14 , further comprising foaming the reactive treatment fluid with CO 2 .

Assignments (3)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Aug 13, 2024
From: ARAMCO SERVICES COMPANY
To: SAUDI ARAMCO UPSTREAM TECHNOLOGY COMPANY
Reel/Frame 068269/0178 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Aug 13, 2024
From: SAUDI ARAMCO UPSTREAM TECHNOLOGY COMPANY
To: SAUDI ARABIAN OIL COMPANY
Reel/Frame 068273/0042 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 7, 2024
From: SAINI, RAJESH KUMAR; HULL, KATHERINE LEIGH; CAIRNS, AMY J.; CRANE, BRADY KEVIN
To: ARAMCO SERVICES COMPANY
Reel/Frame 067652/0492 →
Continuity (1)
Related Publication 20250376614A1 · Dec 11, 2025
References Cited (51)
US 7219731B2 · Sullivan et al. · 2007 [cited by applicant]
US 7500517B2 · Looney et al. · 2009 [cited by applicant]
US 7588085B2 · Acock et al. · 2009 [cited by applicant]
US 7789164B2 · Looney et al. · 2010 [cited by applicant]
US 7857055B2 · Li · 2010 [cited by applicant]
US 9688904B2 · Wang et al. · 2017 [cited by applicant]
US 11124695B2 · Mahmoud et al. · 2021 [cited by applicant]
US 11352548B2 · Hull et al. · 2022 [cited by applicant]
US 11597867B2 · Hull et al. · 2023 [cited by applicant]
US 20030216263A1 · Tibbles et al. · 2003 [cited by applicant]
US 20070087940A1 · Qu et al. · 2007 [cited by applicant]
US 20080039347A1 · Welton · 2008 [cited by examiner]
US 20090139723A1 · Pirolli · 2009 [cited by examiner]
US 20100216672A1 · Todd · 2010 [cited by applicant]
US 20120247774A1 · Li et al. · 2012 [cited by applicant]
US 20130137610A1 · Huang et al. · 2013 [cited by applicant]
US 20140116710A1 · Naser-El-Din et al. · 2014 [cited by applicant]
US 20170066959A1 · Hull et al. · 2017 [cited by applicant]
US 20210024809A1 · Ba Geri · 2021 [cited by examiner]
US 20210198553A1 · Hull · 2021 [cited by examiner]
WO WO0040667 · 2000 [cited by applicant]
WO WO2018187565 · 2018 [cited by applicant]
U.S. Appl. No. 18/732,298, filed Jun. 3, 2024, Hull et al. [cited by applicant]
U.S. Appl. No. 18/735,965, filed Jun. 6, 2024, Hull et al. [cited by applicant]
Abdelgawad et al., “Stimulation of high temperature carbonate gas reservoirs using seawater and chelating agents: Reaction kinetics,” Journal of Natural Gas Science and Engineering, Jul. 2018, 55:595-605, 11 pages. [cited by applicant]
Almubarak et al., “From initial treatment design to final disposal of chelating agents: a review of corrosion and degradation mechanisms,” RSC Adv., Jan. 12, 2022, 12:1813-1833, 21 pages. [cited by applicant]
amcmud.com [online], “AMC Salt Tables,” Available on or before Aug. 2019, retrieved on Aug. 2, 2024, retrieved from URL <https://amcmud.com/wp- content/uploads/sites/2/2019/10/AMC-Salt-Tables-August2019.pdf>, 17 pages. [cited by applicant]
Bageri et al., “Different techniques for characterizing the filter cake,” Presented at the SPE Unconventional Gas Conference and Exhibition, Muscat, Oman, Jan. 2013, 13 pages. [cited by applicant]
Bageri et al., “Effect of Sand Content on the Filter Cake Properties and Removal During Drilling Maximum Reservoir Contact Wells in Sandstone Reservoir,” J. Energy Resour. Technol., May 2016, 138(3):032901-1-032901-10, … [cited by applicant]
Bezemer et al., “Filtration Behavior of Circulating Drilling Fluids,” Society of Petroleum Engineers Journal, Dec. 1966, pp. 292-298, 7 pages. [cited by applicant]
Civan, “A Multi-Phase Mud Filtrate Invasion and Wellbore Filter Cake Formation Model,” Presented at the International Petroleum Conference and Exhibition of Mexico, Veracruz, Mexico, Oct. 1994, pp. 399-412, 14 pages. [cited by applicant]
CRO242ES, “CRONOX™ 242 ES Corrosion Inhibitor,” Safety Data Sheet Brochure, Dec. 17, 2019, 12 pages. [cited by applicant]
Davidson et al., “New and Effective Filter Cake Removal Optimizes Water Injectivity,” Presented at the SPE International Symposium and Exhibition on Formation Damage Control, Lafayette, Louisiana, USA, Feb. 2012, 11 pag… [cited by applicant]
Davison et al., “Oil-Based Muds for Reservoir Drilling: Their Performance and Cleanup Characteristics,” SPE Drilling & Completion, Jun. 2001, 16(2):127-134, 8 pages. [cited by applicant]
drillingfluid.org [online], “Completion and Workover Fluids,” Aug. 30, 2018, retrieved on Aug. 2, 2024, retrieved from URL <https://drillingfluid.org/drilling-fluids-handbook/completion-and-workover-fluids.html>, 4 page… [cited by applicant]
Frick et al., “Horizontal Well Damage Characterization and Removal,” SPE Prod & Frac, Feb. 1, 1993, 8(1):15-22, 8 pages. [cited by applicant]
Gordon et al., “Rheological Properties of Cement Spacer: Mixture Effect,” Prepared for presentation at the 2008 AADE Fluids Conference and Exhibition held at the Wyndham Greenspoint Hotel, Houston, Texas, Apr. 8-9, 2008… [cited by applicant]
Hanssen et al., “New Enzyme Process for Downhole Cleanup of Reservoir Drilling Fluid Filtercake,” Presented at the SPE International Symposium on Oilfield Chemistry, Houston, Texas, Feb. 16, 1999, 13 pages. [cited by applicant]
Hossain et al., “Chapter 3—Drilling Fluids,” Fundamentals of Sustainable Drilling Engineering, 2015, pp. 73-139, 67 pages. [cited by applicant]
Huang et al., “Degradation of high molecular weight polyacrylamide by alkali-activated persulfate: Reactivity and potential application in filter cake removal before cementing,” Journal of Petroleum Science and Engineer… [cited by applicant]
Jaberi et al., “Minimizing the Barite Scale in Carbonate Formations during the Filter Cake Removal Process,” ACS Omega, May 19, 2022, 7(21): 17976-17983, 8 pages. [cited by applicant]
Jaffal et al., “Modeling of filtration and mudcake buildup: An experimental investigation,” Journal of Natural Gas Science and Engineering, 2017, 38:1-11, 11 pages. [cited by applicant]
O-BASF, “Global Oilfield Solutions Corrosion Inhibitors for Production: Basocorr™,” BASF—Global Oilfield Solutions brochure, available on or before Sep. 6, 2017, 6 pages. [cited by applicant]
Rabia, “Chapter 7—Drilling Fluids,” Well Engineering & Construction, 2001, pp. 197-234, 38 pages. [cited by applicant]
Rana et al., “Application of High-Density Brines in Drilling and Completion Fluids: Current Insights and Future Perspectives,” Energy & Fuels, 2024, 38:6561-6578, 18 pages. [cited by applicant]
Shende, “Dissolution of Barite Scale Using Chelating Agents,” A Thesis for the degree of Master of Science, Texas A&M University, May 2012, 68 pages. [cited by applicant]
Siddig et al., “A review of different approaches for water-based drilling fluid filter cake removal,” Journal of Petroleum Science and Engineering, Sep. 2020, 19(107346):1-10, 10 pages. [cited by applicant]
Siddig et al., “A review of the various treatments of oil-based drilling fluids filter cakes,” Journal of Petroleum Exploration and Production Technology, published online on Dec. 22, 2021, 12:365-381, 17 pages. [cited by applicant]
Sosa et al., “Acidic Polysaccharides as Green Alternatives for Barite Scale Dissolution,” ACS Applied Materials & Interfaces, Nov. 24, 2020, 12(49):55434-55443, 10 pages. [cited by applicant]
Thiele et al., “Rapid Dissolution of BaSO [cited by applicant]
Zain et al., “Cleanup of Wall-Building Filter Cakes,” Presented at the SPE Annual Technical Conference and Exhibition, Houston, Texas, Oct. 1999, 14 pages. [cited by applicant]