Temperature Dependent Influence of Nanoparticles on Rheological Properties of VES Fracturing Fluid

Abstract

The use of nanoparticles has been demonstrated to enhance the rheological properties of the viscoelastic surfactant (VES) fluid. However, their influence on the rheological properties as a function of temperature is not well known. In this study, a detailed analysis of improved rheological properties and thermal stability of the VES fluid beyond their optimal working temperature was conducted. The effect of nanoparticles was also studied. A base VES fluid was prepared with the required amount of surfactant along with an ionic strength agent dissolved in sea water. The desired type of nanoparticles in required amounts were added to the base VES fluid and homogeneously dispersed. Different types of nanoparticles were added to prepare corresponding nano-VES fluid. Rheological properties of the base VES fluid and different nano-VES fluids were measured against variable shear rate. The fluids were tested at a temperature at which the base fluid shows highest gelling behavior, and at temperatures above and below that value. Results, Observations, Conclusions: The initial thermo-viscosifying effect and eventual thermo-thinning effect with temperature havebeen widely observed for viscoelastic surfactants based fluids. The effectshavebeen attributed to the effect of temperature on the structural changes of wormlike micelles. Nanoparticles being of the dimensions that are comparable with the thickness of these wormlike micelles are readily able to incorporate themselves into these structures and influence their rheological behavior. These interactions change both with respect to temperature and shear rate applied on them. Further, these interactions differ depending on whether the fluid is in the thermo-viscosifying region or the thermo-thinning region with respect to the temperature. Based on the kind of nanoparticle used, significant improvements in rheological behavior from a fracturing fluid perspective have been observed. In addition, shear rates at which a shift from Newtonian to non-Newtonian behavior with respect to shear rate occurs, has also been observed to change. A greater insight into the effect of nanoparticle additives on temperature related rheology of VES fluids has been provided. This understanding is crucial for the optimization of a VES fracturing fluid based on the well-to-well changes in temperatures.

Review on Enhancing Rheological Characteristics of Viscoelastic Surfactant Fracturing Fluids by Nanoparticles: Advances, Challenges, and Perspectives

“…Nasr-El-Din et al 2 MgO, ZnO Study of performance viscoelastic surfactant by adding nanoparticles Improving the rheological properties of fracturing fluid Gurluk 10 MgO, ZnO Growth of worm-like micelles at high temperature Addition of nanoparticles improves thermal stability and viscosity yield at different shear rates and temperature Aggarwal et al 157 nanocrystal Application of nanoparticles and hydrogel polymer technology to enhance fluid Use of nanotechnology can reduce requirement of VES fluid volume by 60%, permeability range of VES fluid is extended up to 2000 md. Sangaru et al 158 MgO, SiO 2 Improve rheological properties and thermal stability of VES Enhancement of low shear viscosities of VES with adding nanoparticles Ozden et al 159 MgO, ZnO Enhance the VES gel at 350 °F High durability of VES viscosity at 110 cP from 250 to 350 °F Chauhan et al 57 SiO 2 Effects of alkali on the viscosity, thermal stability, and miscibility of VES gel Mixed anionic−anionic system gives improved rheology compared to single anionic and mixed anionic-zwitterionic surfactant systems Wu et al 54 SiO…”

Application of Nanoparticles in Stimulation: A Review

“…Sangaru et al. showed that the addition of NPs to the VES solution prepared in concentrated seawater (total dissolved solids of 63 000 ppm) resulted in a noticeable increase for the apparent viscosity at shear rates less than 10 s –1 . , The experiments were conducted at 300 °F and 500 psi. The apparent viscosity increased almost 4-fold after the addition of NPs.…”

Nanomaterials and Technology Applications for Hydraulic Fracturing of Unconventional Oil and Gas Reservoirs: A State-of-the-Art Review of Recent Advances and Perspectives

“…Due to the instability of VES fracturing fluid under high temperature, high pressure, and high shear rate, some researchers have aimed to significantly improve the temperature and shear resistance of VES fracturing fluids, reduce the fluid loss of VES fracturing fluids, and further enhance the sand-carrying performance of VES fracturing fluids by combining nanomaterials with VES fracturing fluids to take advantage the unique physical and chemical properties of nanomaterials. − Hanafy et al have investigated the effects of the shape, size, and surface properties of nanoparticles on the micellization and cross-linking process of anionic VES fracturing fluid. It was found that the addition of spherical or rod-shaped silica nanoparticles to 4 wt % in an anionic VES system can increase the apparent viscosity by 50% at 280 °F.…”