Theoretical Study On Minimum Wind Volume For Exhausting Radon And Its Progeny In Uranium Mine Blind Roadway Under Different Ventilation Modes

China has been developing nuclear power, the demand for nuclear fuel is increasing. In recent years, the uranium mining industry has also increased greatly, however, the average personal radiation dose of Chinese uranium workers is 3-5 times higher than that of international uranium workers, which gradually drew people's attention for the safety in production of uranium mine. Blind roadway is an important place of uranium mine, where a lot of radon and radon progeny gathered. Because ventilation is the most direct measure for radon reduction, in order to guide the design of reducing radon in uranium blind roadway, in this paper, taking uranium mine blind roadway for object, using the theoretical analysis method under different ventilation mode, studied the distribution of the concentration of radon and radon daughters, and deduced the minimum exhaust volume formulas, the contents and conclusions are as follows:(1)Starting from the introduction of the basics, a detailed descriptionof the properties of radon and its migration mechanism was presented,then simplified alpha-potential growth equation of radon progeny was proposed.(2)The distribution of the roadway pressure of three ventilation modes were analysed, neglecting the reasons for roadway ventilation resistance.(3)The radon and radon daughters concentration distribution model under exhaust ventilation mode was built, according to the force ventilation and exhaust-force ventilation modes, the minimum exhaust volume formulas were deduced from the three ventilation modes. With the numerical simulation, the distribution of radon concentration and the relationships among minimum exhaust volume, exhalation rate and the length of the roadway were analyzed, the results show:1)Under exhaust ventilation mode, radon and radon progeny concentrations increases with the increment of the length of roadway,decreases with the increment of ventilation amount, increases with the increment of exhalation rate; under forced ventilation mode, radon and radon progeny concentrations decreases with the increment of the length of roadway, increases with the increment of exhalation rate; under forced-exhaust ventilation mode, within L2, radon and radon progeny concentrations increases with the increment of length of roadway, within L3, radon and radon progeny concentrations decreases with the incrementof the length of roadway, within L2 and L3, radon and radon progeny concentrations increases with the increment of exhalation rate;2)Under three ventilation modes, the minimum amount of exhaust increases with the increment of exhalation rate; increases with the increment of length of the roadway.