Sugar Alcohols as Crosslinking Delay Additives for Fracturing Fluids

Area of Science:

• Petroleum Engineering
• Materials Science

Background:

• Thermally stable fracturing fluids are crucial for stimulating deep, low-permeability reservoirs.
• Conventional additives for fluid stability face toxicity and environmental challenges.
• Safer alternatives are needed for high-temperature hydraulic fracturing applications.

Purpose of the Study:

• To investigate sugar alcohols as environmentally responsible additives for high-temperature fracturing fluids.
• To evaluate their efficacy as crosslinking delay agents.
• To assess their impact on fluid stability and proppant suspension.

Main Methods:

• A guar-based fluid system was formulated at pH 10.
• High-pressure, high-temperature (HPHT) rheometry was employed at 300 °F for 90 minutes.
• Viscosity, structural recovery, and proppant settling were analyzed under simulated field conditions.

Main Results:

• Sugar alcohols effectively delayed crosslinking, enabling controlled viscosity development.
• Optimized systems (2 ppt sugar alcohol, 4 gpt zirconium crosslinker) achieved 600 cP peak viscosity, maintaining >300 cP for 90 minutes.
• Controlled viscosity reduction was observed with breakers, and >95% proppant suspension was confirmed.

Conclusions:

• Sugar alcohols show significant potential as effective and environmentally safer crosslinking delay additives.
• They enhance the stability and performance of fracturing fluids at elevated temperatures.
• This research supports the use of sugar alcohols in sustainable hydraulic fracturing operations.