Gelation Time of Hexamethylenetetramine Polymer Gels Used in Water Shutoff Treatment

Document Type: Research Paper

Authors

Chemical Engineering Department, Tarbiat Modares University

Abstract

Among the methods available to reduce water production, injecting a gelling system composed of a polymer and a crosslinker has been widely used. In this work, a hydrogel was prepared by crosslinking of an aqueous solution containing hexamethylenetetramine (HMTA) as crosslinker, hydrochloric acid (HCl) as an activator, and the co-polymer of 2-acrylamido-2methyl-propanesulfonic-acid sodium salt (AMPS) and acrylamide (PAMPS). In order to indicate the effective factors on the gelation time and also to develop the quadratic mathematical models, central composite design (CCD) was applied. Therefore, the main purpose was to establish functional relationship between the three factors (polymer concentration, HMTA, and hydrochloric acid) and a response (gelation time) by using a statistical technique. In order to determine the optimum value of these factors for maximum gelation time, a simultaneous optimization was also applied. The results of the analysis of variance (ANOVA) of the developed model illustrated that the fitted model was significant in a 99% confidence limit. The results showed that hydrochloric acid was identified as the main factor effecting the gelation time and there was also an interaction between HMTA and hydrochloric acid. Finally, a mechanism for the reaction between PAMPS and HMTA were presented.

Keywords


[1]. Albonico P., and Lockhart T., “Divalent Ion-resistant Polymer Gels for High Temperature Applications: Syneresis Inhibiting Additives”, Presented at the International Symposium on Oilfield Chemistry. New Orleans. March 1993; Paper SPE 25220.

[2]. Al-Muntasheri Gh., and Zitha P., “Gel under Dynamic Stress in Porous Media: New Insight Using Computed Tomography”, Presented at the Saudi Arabia Section Technical Symposium and Exhibition held in AlKhobar. Saudi Arabia. May 2009; Paper SPE 126068.

[3]. Hardy M., Botermans W., Hamouda A., Valdal J., and Warren J., “The First Carbonate Field Application of a New Organically Crosslinked Water Shutoff Polymer System”, Presented at the International Symposium on Oilfield Chemistry held in Houston. Texas.February 1999; Paper SPE 50738.

[4]. Needham R., Threlkeld C., and Gall J. “Control of Water Mobility Using Polymers and Multivalent Cations”, Presented at the 1974 SPE-AIME Improved Oil Recovery Symposium, Tulsa. April 1974; Paper SPE 4747.

[5]. Moffit P., Moradi-Araghi A., Janway V., and Young G., “Development and Field Testing of a New Low Toxicity Polymer Crosslinking System”, Presented at the Permain Basin Oil & Gas Recovery Conference held in Midland. Texas. March 1996; Paper SPE 35173.

[6]. Moradi-Araghi A. “A Review of Thermally Stable Gels for Fluid Diversion in Petroleum Production”, Journal of Petroleum Science and Engineering, 26: pp. 1–10, 2000.

[7]. Moradi-Araghi A. Application of Low Toxicity Crosslinking Systems in Production of Thermally Stable Gels, Presented at the SPE/DOE Ninth Symposiumon Improved Oil Recovery, Tulsa, Paper SPE/DOE 27826, April 1994.

[8]. Hutchins R., Dovan H., and Sandiford B. “Field Applications of High Temperature Organic Gels for Water Control”, Presented at the 10th SPE/DOE Improved Oil Recovery Symposium. Tulsa, Paper SPE/DOE 35444, April 1996.

[9]. Dovan H., Hutchins R., and Sandiford B. “Delaying Gelation of Aqueous Polymers at Elevated Temperatures Using Novel Organic Crosslinkers”, Presented at the International Symposium on Oilfield Chemistry. Texas.; Paper SPE 37246, February 1997.