Experimental study on coupling characteristics of radon exhalation from surrounding rock of deep uranium mines

Considering the significant issue of radon contamination in deep uranium mining settings, an investigation was conducted on the mechanical-environmental coupling effects of various joint roughness coefficients (JRC), temperature (T), pressure differential (ΔP), water saturation degree (K_w), and ventilation intensity (λ_v) on the surface radon exhalation of quasi-uranium ore samples. This was accomplished through the utilization of a self-constructed rock radon coupling exhalation experimental device and quasi-uranium ore sample. The findings indicate that the radon concentration in the sample increases in a linear fashion with the duration of radon collection, irrespective of the sample’s temperature. Furthermore, the radon exhalation capacity of the sample exhibits an initial rise followed by a decline as the degree of water saturation increases. As the sample pressure differential increases, the radon exhalation capacity of the sample exhibits a monotonically decreasing pattern. The concentration of accumulated radon is inversely associated with the intensity of ventilation. The relationship between the radon exhalation ability of the sample and the JRC is generally manifested in the form of “first decreasing and then increasing”, and the maximum and minimum values of the radon exhalation ability occur in the cases of JRC = 16–18 and JRC = 6–8, respectively. The results of this study can provide scientific basis for the design of ventilation and radon control in future deep uranium mines.