Affiliation:
1. Saudi Aramco EXPEC ARC, Dhahran, Saudi Arabia
Abstract
Abstract
High-temperature fracturing fluids are in demand as we explore deeper and lower permeability reservoirs. Fracturing fluid stabilizers are divided into three categories: crosslinking delay additives, pH buffers, and reducing agents. Current technologies pose risks due to toxicity concerns and their harmful environmental effects. Consequently, the industry is continuously pushing towards green solutions. This work showcases the use of low-calorie sweeteners such as polyols as an environmentally friendly fracturing fluid additive.
The paper presents a guar derivative fracturing fluid system prepared at pH 10. The tests were performed in a high-pressure/high-temperature (HPHT) rheometer to evaluate the rheological performance at 300°F for 1.5 hours. The rheological schedule measured viscosity at 100 s-1 shear rate with varying lower shear rates ramps in between. Experiments are completed to recognize how polyols influence the rheological behavior of the fracturing fluid under a variety of crosslinker concentrations.
The results showed that using polyols can function as a crosslinking delay additive to control viscosity buildup, thus aiding in high-temperature stability. This was determined by varying the ratio of polyol to crosslinker concentration. Achieving a balance between the polyol and crosslinker concentration produced fracturing fluids that maintain a viscosity above 300 cp for 1.5 hours at temperatures of 300°F. Common oxidizer breakers were evaluated with this system and exhibited a controlled viscosity breakdown profile at these conditions. Proppant settling tests were also shared and showed the ability to suspend proppant for the duration of the treatment.
This study shares the use of polyols in fracturing fluids. Polyols not only provide excellent crosslinking delay properties but also protect organisms and the environment by mitigating the toxicity and health-damaging effects of commonly used high-temperature stabilizers.