Degradable Gel for Temporary Plugging in High Temperature Reservoir and Its Properties

Area of Science:

• Materials Science
• Petroleum Engineering
• Polymer Chemistry

Background:

• Temporary plugging gels are crucial in oil fields but often degrade prematurely at high temperatures.
• Existing degradable gels lack sufficient thermal stability for demanding downhole conditions.

Purpose of the Study:

• To synthesize and characterize a novel degradable gel with enhanced high-temperature stability for oil field applications.
• To investigate the factors influencing the gel's degradation rate and performance.

Main Methods:

• Synthesis of an unstable crosslinker to create a high-temperature degradable gel.
• Analysis of gel structure and thermal stability using FTIR, 13C NMR, and TG.
• Evaluation of viscoelastic, compressive, plugging, and core damage performance.

Main Results:

• The gel's degradation time is controllable between 90-130 °C via crosslinker concentration.
• High plugging pressure (>15 MPa) and low core damage (<5%) were achieved in sand-filled tubes.
• Degradation involves network collapse via hydrolysis, resulting in low-viscosity liquid (<11 mPa·s).

Conclusions:

• The developed degradable gel exhibits excellent high-temperature stability and tunable degradation.
• It offers effective temporary plugging with minimal formation damage and easy cleanup.
• This material presents a promising solution for challenging oil field operations.