A New Strategy for Minimizing Precipitations during ASP Flooding in Carbonate Reservoirs
Abstract:A large quantity of world-s oil reserves exists in
carbonate reservoirs. Carbonate reservoirs are very sensitive to
chemical enhanced oil recovery process because of containing large
amount of calcite, dolomite and calcium sulfate minerals. These
minerals cause major obstacles during alkali-surfactant-polymer
(ASP) flooding. Alkali reacts with these minerals and form undesired
precipitations which plug effective porous openings, reduce
permeability and cause scale occurrence at the wellbore. In this
paper, a new chemical combination consists of acrylic acid and alkali
was used to minimize precipitation problem during ASP flooding. A
series of fluid-fluid compatibility tests were performed using acrylic
acid and different concentrations of alkaline. Two types of alkalis
namely; sodium carbonate and sodium metaborate were screened. As
a result, the combination of acrylic acid and sodium carbonate was
not effective in preventing calcium and magnesium precipitations.
However, acrylic acid and sodium metaborate showed promising
results for keeping all solutions without any precipitations. The ratio
of acrylic acid to sodium metaborate of 0.7:1.0 was found to be
optimum for achieving a compatible solution for 30 days at 80oC.
 J. Vargo et al., "Alkaline-Surfactant-Polymer Flooding of the Cambridge
Minnelusa Field," History, no. September, pp. 15-18, 2000.
 S. Liu, O. Oil, G. Corporation, R. F. Li, C. A. Miller, and G. J. Hirasaki,
"Alkaline / Surfactant / Polymer Processes: Wide Range of Conditions
for Good Recovery," SPE Journal, no. June, 2010.
 M. M. Ansarizad, "SP Alkaline S Surfactant Polymer Flood ding To R
Revitalize e Oil Production from a Mature ater Flooded Field,"
 D. B. Levitt, S. Dufour, G. Pope, D. Morel, and P. Gauer, "IPTC 14915
Design of an ASP flood in a High-Temperature , High-Salinity , Low-
Permeability Carbonate," interactions, pp. 1-19, 2012.
 M. A. Bataweel and A. Texas, "SPE 143155 Alternatives to Minimize
Scale Precipitation in Carbonate Cores Caused by Alkalis in ASP
Flooding in High Salinity / High Temperature Applications," no. 1984,
 A. M. Al, H. A. Nasr, K. U. Raju, and S. Aramco, "SPE 80402 Scale
Inhibitor Squeeze Treatment in a Tight Carbonate Reservoir - Problems
and Solutions," Production, 2003.
 T. Larsen, P. Randhol, M. Lioliou, and I. C. E. Ht, "SPE 114045
Kinetics of CaCO 3 Scale Formation During Core Flooding,"
 S. P. E. Doe, "Spe/doe," Energy, 1990.
 V. Obiora, F. Fernartdez, W. Nofal, K. Fahd, and S. Arabia, "Alkaline
Surfactant Polymer Formulation for Saudi Arabian Carbonate
Reservoirs," Polymer, 1996.
 M. S. Zakaria, A. A. Yaacob, and U. Engineering, "SPE 109033
Meeting the Challenges in Alkaline Surfactant Pilot Project
Implementation at Angsi," Water, 2007.
 K. A. Elraies, I. M. Tan, M. Awang, U. T. Petronas, M. T. Fathaddin,
and U. Trisakti, "SPE 133004 A New Approach to Low-Cost , High
Performance Chemical Flooding System," SPE Production And
 K. A. Elraies, I. M. Tan, and U. T. Petronas, "SPE 133005 Design and
Application of a New Acid-Alkali-Surfactant Flooding Formulation for
Malaysian Reservoirs," Society, 2010.
 K. Mohan, "SPE-129516-STU Alkaline Surfactant Flooding for Tight
Carbonate Reservoirs," Society, no. October, pp. 4-7, 2009.
 A. Flaaten, Q. Nguyen, J. Zhang, H. Mohammadi, and G. Pope, "ASP
Chemical Flooding Without the Need for Soft Water," Proceedings of
SPE Annual Technical Conference and Exhibition, Sep. 2008.
 J. Zhang, Q. P. Nguyen, A. K. Flaaten, and G. A. Pope, "Mechanisms of
Enhanced Natural Imbibition with Novel Chemicals," vol. 2, no. 1, pp.