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# c12) United States Patent Sarda et al. 

# (54) IN-SITU CROSSLINKING AND CALCIUM ION COMPLEXATION FOR ACIDIZING A SUBTERRANEAN FORMATION 

(71) Applicant: HALLIBURTON ENERGY SERVICES, INC., Houston, TX (US) 

(72) Inventors: Anjali Ramesh Sarda, Pune (IN); Shoy George Chittattukara, Thissur (IN); Anupom Sabhapondit, Pune (IN) 

(73) Assignee: Halliburton Energy Services, Inc., Houston, TX (US) 

( *) Notice: Subject to any disclaimer, the term ofthis patent is extended or adjusted under 35 U.S.C. 154(b) by 192 days. This patent is subject to a terminal dis› claimer. 

(21) Appl. No.: 13/661,106 

(22) Filed: Oct. 26, 2012 

## (65) Prior Publication Data 

US 2014/0116707 Al May 1, 2014 

(51) Int. Cl. 

<img src='content_image/940014.jpg'>

(52) U.S. Cl. CPC ... C09K 8174 (2013.01); C09K 8176 (2013.01); C09K 2208/32 (2013.01) 

( 58) Field of Classification Search CPC ......................................................... C09K 8/74 See application file for complete search history. 

## (56) References Cited 

<img src='content_image/940015.jpg'>

## U.S. PATENT DOCUMENTS 

<img src='content_image/939982.jpg'>

# (IO) Patent No.: US 9,399,728 B2 

# (45) Date of Patent: *Jul. 26, 2016 

<img src='content_image/940016.jpg'>

EP 0278540 Bl 8/1992 

PCT/US2013/060035, International Search Report, dated Dec. 9, 2013, 5 pages. 

Written Opinion dated Dec. 9, 2013 for Application No. PCT/ US2013/060035. 

Jain, R. et al., "Reaction Kinetics of the Uptake of Chromium (III) Acetate by Polyacrylarnide" SPE Paper 89399, SPE Journal (Sep. 2005), pp. 247-254. 

* cited by examiner 

Primary Examiner - Angela M Di Trani 

Assistant Examiner - Andrew H Sue-Ako 

(74) Attorney, Agent, or Firm - Craig W. Roddy; Baker Botts L.L.P. 

## (57) ABSTRACT 

A method of treating a zone of a subterranean formation penetrated by a wellbore, the method including the steps of: (a) forming a treatment fluid comprising: (i) water; (ii) a strong acid); (iii) a water-soluble polymer having at least one functional group that can be crosslinked with aluminum(III); (iv) a water-soluble aluminum carboxylate; and (v) a com› plexion agent for calcium ions; wherein the pH of the treat› ment fluid is less than the pH required for the aluminum to crosslink the polymer to form a crosslinked gel; (b) introduc› ing the treatment fluid through the well bore into the zone; and ( c) allowing time for the strong acid in the treatment fluid to spend in the formation such that the pH of the fluid increases sufficiently for the aluminum of the aluminum carboxylate to crosslink the polymer. 

US009399728B2 

## FOREIGN PATENT DOCUMENTS 

## OTHER PUBLICATIONS 

## 23 Claims, No Drawings 

