Development of Novel Drilling-Fluid Nanoparticles for Enhanced Drilling Operations

Abstract

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper IPTC 18381, “Development and Testing of Novel Drilling Fluids Using Fe2O3 and SiO2 Nanoparticles for Enhanced-Drilling Operations,” by Zisis Vryzas, Texas A&M University at Qatar; Omar Mahmoud and Hisham A. Nasr-El-Din, Texas A&M University; and Vassilios C. Kelessidis, Texas A&M University at Qatar, prepared for the 2015 International Petroleum Technology Conference, Doha, Qatar, 7–9 December. The paper has not been peer reviewed. Copyright 2015 International Petroleum Technology Conference. Reproduced by permission. This work focuses on the laboratory techniques for developing, assessing, and analyzing innovative water-based drilling fluids containing iron oxide (Fe2O3) and silica (SiO2) nanoparticles. The examined nanoparticles have the potential to significantly improve the characteristics of the filter cakes at both low-pressure/low-temperature (LP/LT) and high-pressure/high-temperature (HP/HT) conditions. They also have the ability to maintain optimal rheological properties so that many drilling problems can be mitigated efficiently. Introduction Drilling-fluid loss is considered the major source of capital expenditure during drilling operations. Nanoparticles have proved to be more effective in reducing the filtrate losses than conventional fluid-loss reducers. Because they exhibit different adsorption and transportation behavior in different porous media, nanoparticles have been used successfully as stabilizers in emulsions and foams, as rheology modifiers, and as fluid-loss additives in surfactant/polymer or water-based drilling fluids. Addition of Fe2O3 and SiO2 nanoparticles can improve or at least maintain fluid properties even at high temperatures. This work aims to find the optimal concentration of such nanoparticles. Experimental Procedure Materials and Sample Preparation. Bentonite was supplied in powder form; the water/bentonite suspension gives a mixture with a pH range of 8 to 10. The Fe2O3 nanoparticles were purchased in powder form with a spherical shape and an average diameter of less than 50 nm with a purity greater than 97%. Nanosilica was purchased in powder form with a spherical shape and an average diameter of 12 nm with a purity greater than 99.5%. Deionized water with pH range 6.8 to 7.2 was used along with the bentonite to prepare the base fluid. All the prepared samples had pH in the range of 7.9 to 8.3. The preparation of the samples was carried out following American Petroleum Institute (API) standards. The base fluid (BF) was formulated with a bentonite concentration of 7.0 wt% in 600 cm3 of deionized water. Different concentrations of Fe2O3 and SiO2 nanoparticles were used (0.5, 1.5, and 2.5 wt%). First, bentonite was added to deionized water and mixed for 20 minutes. The desired concentration of nanoparticles was added slowly to minimize the agglomeration, and mixing continued for 20 more minutes. The samples were then sealed in plastic containers and left for 16 hours at room temperature for the bentonite to hydrate.