Session: 11-02-02 Well Drilling Fluids and Hydraulics-2

Submission Number: 180766

Investigation of Temperature and Density Effects on the Rheological Properties of Water-Based Drilling Muds 

Optimal selection of drilling mud type and its components plays a crucial role in preserving formation productivity, enhancing wellbore stability and cuttings transport. Since pressure increases with depth, drilling companies predominantly utilize barite as a weighting agent in water-based drilling muds. However, due to using these additives during the penetration of the productive formation, some of the particles may reduce filtration characteristics of the reservoir. Some of the fine weight material particles may enter into the formation. As their removal from the pore channels is nearly impossible. Furthermore, there is the risk of barite sag, where the barite particles settle over time, leading to potential complications in wellbore stability and fluid distribution.

The experimental procedure involved preparing a base fluid by mixing distilled water with KCl, then adding two types of polymers (PAC and xanthan gum), barite, and NaOH to increase the pH. Various mud tests were conducted, including preparation and detailed rheological analysis. The rheological properties of the drilling mud were measured at different densities (1.60, 1.40, and 1.20 sg), across a temperature range (10°C to 90°C), and under varying shear rates to identify trends for predicting the behavior of drilling fluids.

The results indicate that shear stress increases with shear rate, exhibiting a non-Newtonian behavior. Furthermore, higher specific gravity which is due to higher concentrations of barite and lower temperatures, leads to higher shear stress values, which shows viscosity increased under these conditions. The findings demonstrate that the rheological properties of fluid are influenced significantly by both temperature and specific gravity which means with higher temperatures resistance to shear reduces, making the fluid less viscous.

The density was modified by adjusting the amount of barite, a common weighting material. The findings highlight the complex relationship between temperature and density, revealing how variations in density can counteract the impact of temperature on viscosity. This insight is particularly valuable for industries relying on precise flow behavior, such as drilling fluids, food processing, and polymer engineering, where optimizing viscosity is crucial for efficiency and performance.

Presenting Author: Masoumeh Amiri Mikal University of Stavanger

Presenting Author Biography: PhD researcher in Petroleum Engineering at the University of Stavanger, specializing in drilling fluid rheology, laboratory experimentation, and modeling. Proficient in advanced rheological measurements, MATLAB simulations, COMSOL, SolidWorks, and Design Expert. Experienced in the characterization and optimization of bentonite-based, water-based, and oil-based drilling fluids.

Authors:

Masoumeh Amiri Mikal University of Stavanger
Arild Saasen University of Stavanger