Table of Contents
Journal of Petroleum Engineering
Volume 2014, Article ID 864624, 7 pages
http://dx.doi.org/10.1155/2014/864624
Research Article

A Novel Method for Improving Water Injectivity in Tight Sandstone Reservoirs

1Petroleum Engineering Department, The Petroleum Institute, P.O. Box 2533, Abu Dhabi, UAE
2Department of Petroleum & Geosystems Engineering, The University of Texas Austin, Austin, TX 78712, USA

Received 15 July 2014; Accepted 23 August 2014; Published 21 September 2014

Academic Editor: Yunho Hwang

Copyright © 2014 Mohamad Yousef Alklih et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Applicability of electrokinetic effect in improving water injectivity in tight sandstone is studied. DC potential and injection rate are varied for optimization and determination of their individual impact on clay discharge and movement. The liberated clays were characterized through size exclusion microfiltration and ICP-MS analysis. Real time temperature and pH monitoring were also informative. Results showed that severalfold (up to 152%) apparent increase of core permeability could be achieved. Some of the experiments were more efficient in terms of dislodgement of clays and enhanced stimulation which is supported by produced brines analysis with higher concentration of clay element. The results also showed larger quantity of clays in the produced brine in the initial periods of water injection followed by stabilization of differential pressure and electrical current, implying that the stimulation effect stops when the higher voltage gradient and flow rates are no more able to dislodge remaining clays. Additionally, fluid temperature measurement showed an increasing trend with the injection time and direct proportionality with the applied voltage. The basic theory behind this stimulation effect is predicted to be the colloidal movement of pore lining clays that results in widening of pore throats and/or opening new flow paths.