Study on the characteristics of radon exhalation from fly ash filling materials in coal fire goaf based on the evolution of pore structure

Large amount of inhalation of the radon exacerbates the risk of cancer in the human body, and human beings also pay more attention to the problem of environmental pollution. With the increasing mining of underground mineral resources, coal production has increased significantly, but at the same time, it has also increased the number of underground goaf, and it has also seriously increased the potential danger of spontaneous combustion in the goaf. The influence of thermal effect on pore structure and radon exhalation characteristics was studied by means of relevant measurement. The outcomes confirmed that the radon exhalation characteristics of fly ash increased linearly with the increase of temperature and then decreased exponentially. At 400 degrees C, the radon exhalation rate of fly ash is the highest, which is 8.41 Bq m-2 h-1, 2.11 times that of fly ash at normal temperature. This is closely related to the change in pore structure of fly ash after heat treatment. The research results in this study are significant for assessing the radiation risk of radon in fly ash.