Study on the real-time radon release pattern of granite under temperature-pressure coupling

Area of Science:

• Geosciences
• Environmental Science
• Nuclear Engineering

Background:

• Uranium ore mining releases radioactive radon gas.
• Understanding radon release from granite under deep stratum conditions is crucial for safety.
• Temperature-pressure coupling effects on radon release in granite require investigation.

Purpose of the Study:

• To investigate the law of radon gas release from granite under temperature-pressure coupling.
• To explore the effect of varying temperatures on radon release behavior in granite.
• To provide a basis for scientific prevention and control strategies for radon release.

Main Methods:

• Uniaxial compression experiments on granite under diverse temperature gradients (25°C to 300°C).
• Real-time monitoring of radon release changes during experiments.
• Analysis of radon release patterns in relation to strain and temperature.

Main Results:

• Granite radon release increases with strain, peaks during crack propagation, then decreases, and increases again.
• Radon exhalation decreased by 28.45% at 100-150°C (compression/densification) and increased by 29.33% at 150-200°C (crack expansion).
• High temperatures decrease granite's mechanical properties, accelerate water evaporation, and promote thermal expansion, enhancing radon release.

Conclusions:

• Temperature-pressure coupling significantly influences radon release behavior in granite.
• Microcrack generation and expansion under elevated temperatures create new pathways for radon migration.
• Findings are essential for understanding radon release dynamics and developing mitigation strategies in deep mining environments.