Effect of Corrosion–Inhibitor Chemistry on the Viscosity and Corrosion Rate of VES-Based Acids
- Ahmed Hanafy (Texas A&M University) | Hisham Nasr-El-Din (Texas A&M University) | Ahmed Rabie (Solvay) | Jian Zhou (Solvay)
- Document ID
- Society of Petroleum Engineers
- SPE International Conference on Oilfield Chemistry, 8-9 April, Galveston, Texas, USA
- Publication Date
- Document Type
- Conference Paper
- 2019. Society of Petroleum Engineers
- 2.5.2 Fracturing Materials (Fluids, Proppant), 2.6 Acidizing, 2 Well completion, 1.10 Drilling Equipment, 4.2.3 Materials and Corrosion, 1.10 Drilling Equipment, 2.4 Hydraulic Fracturing
- high temperature, self diverting acid, corrosion inhibitor, viscoelastic surfactants
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- 139 since 2007
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Viscoelastic surfactants (VES) are essential components in self-diverting acid systems. Their low thermal stability limits their application at elevated temperatures. The industry introduced new VES chemistries with modified hydrophilic functional groups, which enhances their thermal stability. These new chemistries are still challenged by the lack of compatibility with corrosion inhibitors (CI). This work aims to study the nature and the mechanism of the interaction between the VES and the corrosion inhibitors, which affects both the rheological and corrosion inhibition characteristics of the self-diverting acid system.
This study is based on rheology and corrosion inhibition tests, where combinations of VES and corrosion inhibitors are tested and complemented with chemical and microscopic analysis. Negatively charged thiourea and positively charged quaternary ammonium corrosion inhibitors were selected to study their impact on both cationic and zwitterionic VES systems. Each mixture of the corrosion inhibitor and the VES was blended in a 15 and 20 wt% HCl acid mixture, then assessed for its viscosity at different shear rates, CI concentrations, and temperatures up to 280°F in live and spent acid conditions. Each acid solution was assessed using Fourier-Transform-Infra-Red (FTIR) before and after each rheology and corrosion test to track the changes of the mixture functional groups. Each mixture was examined under a polarizing microscope to assess its colloidal nature. The corrosion inhibition effectiveness of selected acid mixtures was evaluated. N-80 steel coupons were immersed statically in the acid mixture for 6 hours at 150°F and 1,000 psi. The corrosion rate was evaluated by using metal coupon weight loss analysis followed by optical microscope examination for the metal surface.
The interaction between the CI and the VES surface charges and molecular geometries dictates both the rheological and the inhibitive properties of the acid mixtures. The use of a small molecular structure anionic CI with a cationic VES, results in a fine monodispersed CI particles in the VES-acid system. The opposite charges between the CI and the VES results in electrostatic attraction forces. Both the fine dispersion and the electrostatic attraction enhances the rheological performance of the mixture and packs the corrosion-inhibiting layer. The addition of a bulk and similarly charged CI with the VES results in a coarse polydispersed CI particles with repulsive nature with the VES. These properties increase the shear-induced structures and lower the packing of the inhibition layer deposited on the metal coupons, which decrease the rheological performance of the acid mixture and increase its corrosion rate. The FTIR analysis shows that there is no chemical reaction between the CIs and the VESs tested.
This work investigates the interactions between the corrosion inhibitors and the viscoelastic surfactants. It explains the impact of the surface charge of both corrosion inhibitors and VES on their rheological and corrosion inhibition characteristics. It adds a selection criterion for compatible VES and corrosion inhibitors.
|File Size||1 MB||Number of Pages||18|
Al-Mutairi, S. H., Nasr-El-Din, H. A., Aldriweesh, S. M.. 2005. Corrosion Control during Acid Fracturing of Deep Gas Wells: Lab Studies and Field Cases. Presented at the SPE International Symposium on Oilfield Corrosion, Aberdeen, United Kingdom, 13 May. SPE-94639-MS. https://doi.org/10.2118/94639-MS.
Al-Mutairi, S. H., Hill, A. D., and Nasr-El-Din, H. A. 2007. Effect of Droplet Size, Emulsifier Concentration and Acid Volume Fraction on the Rheological Properties and Stability of Emulsified Acids. Presented at the European Formation Damage Conference, Scheveningen, The Netherlands, 30 May-1 June. SPE-107741-MS. https://doi.org/10.2118/107741-MS.
Al-Mutawa, M., Al-Anzi, E. H. D., Jemmali, M.. 2005. Zero Damaging Stimulation and Diversion Fluid: Field Cases from the Carbonate Formations in North Kuwait. SPE Prod & Fac 20 (2):94-105. SPE-80225-PA. https://doi.org/10.2118/80225-PA.
Chang, F. F., Qu, Q., and Frenier, W. 2001. A Novel Self-Diverting-Acid Developed for Matrix Stimulation of Carbonate Reservoirs. Presented at the SPE International Symposium on Oilfield Chemistry, Houston, Texas, 13-16 February. SPE-65033-MS. https://doi.org/10.2118/65033-MS.
Di Lullo, G., bte Ahmad, A., Rae, P.. 2001. Toward Zero Damage: New Fluid Points the Way. Presented at the SPE Latin American and Caribbean Petroleum Engineering Conference, Buenos Aires, Argentina, 25-28 March. SPE-69453-MS. https://doi.org/10.2118/69453-MS.
Hull, K. L., Sayed, M., and Al-Muntasheri, G. A. 2016. Recent Advances in Viscoelastic Surfactants for Improved Production from Hydrocarbon Reservoirs. SPE J. 21 (4): 1,340-1,357. SPE-173776-PA. https://doi.org/10.2118/173776-PA.
Li, L., Nasr-El-Din, H. A., Crews, J. B.. 2011. Impact of Organic Acids/Chelating Agents on the Rheological Properties of an Amidoamine-Oxide Surfactant. SPE Prod & Oper 26 (1): 30-40. SPE-128091-PA. https://doi.org/10.2118/128091-PA.
Nasr-El-Din, H. A., Al-Ghamdi, A. H., Al-Qahtani, A. A.. 2008. Impact of Acid Additives on the Rheological Properties of a Viscoelastic Surfactant and Their Influence on Field Application. SPE J. 13 (1): 35-47. SPE-89418-PA. https://doi.org/10.2118/89418-PA.
Rostami, A. and Nasr-El-Din, H. A. 2009. Review and Evaluation of Corrosion Inhibitors Used in Well Stimulation. Presented at the SPE International Symposium on Oilfield Chemistry, The Woodlands. Texas, 20-22 April. SPE-121726-MS. https://doi.org/10.2118/121726-MS.
Samuel, M., Card, R. J., Nelson, E. B.. 1997. Polymer-Free Fluid for Hydraulic Fracturing. Presented at the SPE Annual Technical Conference and Exhibition, San Antonio, Texas, 5-8 October. SPE-38622-MS. https://doi.org/10.2118/38622-MS.
Woodroof, R. A., Baker, J. R., and Jenkins, R. A. 1975. Corrosion Inhibition of Hydrochloric - Hydrofluoric Acid/Mutual Solvent Mixtures at Elevated Temperatures. Presented at the Fall Meeting of the Society of Petroleum Engineers of AIME, Dallas, Texas, 28 September-1 October. SPE-5645-MS. https://doi.org/10.2118/5645-MS.
Yu, M., Mu, Y., Wang, G.. 2012. Impact of Hydrolysis at High Temperatures on the Apparent Viscosity of Carboxy Betaine Viscoelastic Surfactant-Based Acid: Experimental and Molecular Dynamics Simulation Studies. SPE J. 17 (4): 1,119-1,130. SPE-142264-PA. https://doi.org/10.2118/142264-PA.