Journal of Petroleum and Gas Exploration Research (ISSN 2276-6510) Vol. 4(4) pp. 60-71, September 2014. DOI: http:/dx.doi.org/10.14303/jpger.2014.018. Copyright © 2014 International Research Journals

 

Full length research paper

Environmentally Friendly Water-Based Drilling Fluid for Drilling of Water-Sensitive Formations

*1Mr Hamed Behnamanhar 2Dr S. Shamsollah Noorbakhsh 3Mr Hoseinali Maghsoudloojafari

1University of Tehran Iran 2NIOSC Iran 3Faculty of Petroleum and Renewable Energy Engineering, Universiti Teknologi Malaysia, Skudai, Malaysia

*Corresponding authors e-mail: harabi98@ut.ac.ir

Abstract

 

Drilling of shale and clay-rich geological formations are always challenging because of their instability and water sensitivity. Oil-based drilling fluids (OBDF) are widely used in drilling operations, especially in highly technical wells. OBDF systems perform much better than water based drilling fluid (WBDF) in borehole stabilization and they allow faster penetration rates. Additionally, one of the most important features of OBDF is its high lubricity especially for deviated wells. Although OBDF prevents many problems of drilling the shale formations, they have negative impacts on the environment. So, there are many efforts to replace them by a water based and environmentally friendly drilling fluid. In this research, by investigation of drilling history and according to the results of studies accomplished on Iranian shale formations, a water-based and environmentally friendly drilling fluid has been developed. This fluid has improved properties such as high filtration control, reduced formation damages, diminished clay activities, stability against high temperature, cutting stability, acidity alteration and compatibility with any contaminations which may be entered to the drilling fluid during the drilling operations. Lubrication and cutting (shale cuttings) removal of this developed fluid are superior. New additives containing meshed solid particles, inhibitive agents and synthesized polymers were used to develop this fluid

Keywords: Environmentally friendly drilling fluid; Borehole Instability; Shale; Water Based Drilling Fluid; Oil Based Drilling Fluid; Glycol