The Design of Improved Water Based Mud (WBM) By Using Nanosilica and Its Performance on Maintaining Shale Stability

Wellbore stability in shale formation has long been a significant issue in petroleum drilling industry for over century. The major cause of wellbores stability problem in shale formation facing by many drilling engineers actually originated from interaction between water-based muds with shale. The adsorption of water particle by shale will force the clay mineral to swell. This particular phenomenon of shale swelling will lead to various stability problems such and eventually lead to wellbore failure. In this project, a study on an improved water-based mud (WBM) containing nanoparticle (nanosilica) and its performance in maintaining wellbore stability in shale formation will be showed.
This project will show the process of producing nanosilica from siliceous sand. Due to its commercial availability, this nanosilica can be easily engineered to meet the specification of the formation especially the particle size. Characterization of the nanosilica was completed by using Transmission Electron Microscope (TEM). The analysis on nanosilica particle size shows that it is suitable for providing plugging mechanism in WBM. The use of nanoparticle such as nanosilica to decrease the water adsorption of shale by physically plugging nanoscale pores holds the potential to remove a major hurdle in confidently applying water-base mud in shale formation.
In this project, rheological properties of designated WBM are determined to analyze the relationship between nanosilica concentration and various rheological properties.
Ultimately, this project includes the study of fluid loss and plugging effect with respected to concentration of nanosilica in WBM by using laboratory experimental approach. Therefore, a deeper understanding on wellbore stability in shale formation can be achieved through this project.