Abstract: There is a risk of radioactive sodium aerosol diffusion in severe sodium fire accidents, which needs to be controlled. As one of the aerosol control technologies, atomization fixation technology has the advantages of flexibility and efficiency, and has been successfully applied in the field of radioactive aerosol control in foreign nuclear facilities. To explore the feasibility of applying atomization fixation technology in sodium fire protection systems, sodium aerosol suppression experiments were conducted under different droplet size conditions of fixative. Experiments have shown that for sodium carbonate aerosols with a total particle concentration of 105 and a peak particle size of 1 μm, when using a fixed agent at a dosage of 250 mL/m3 and a viscosity of (143.4±3) cp, the settling rates of large (43.055 μm), medium (13.057 μm), and small (8.773 μm) fixed agent droplets pressing sodium aerosols within 30 minutes are 9.10%, 26.60% and 38.55%, respectively. The corresponding average decrease rates of aerosol particle number concentration are 1 099, 1 242 and 1 787 P/(cm3·min), respectively. This is consistent with the theoretical trend that the smaller the droplet of the fixative, the better the compression effect. By disturbing the fixed agent that has settled on the ground, it was determined that the droplet size of the fixed agent has no significant effect on the resuspension effect, and it was also verified that this technology can successfully adhere the aerosol to the ground.

Key words: sodium fire accident, sodium aerosol control, atomization fixation technology, gas liquid two-phase flow atomizer