Radiation Dose Calculation Of Spallation Targets In ADS

Accelerator Driven Sub-critical System (ADS) becomes a new option of nuclear energy, due to its good cost efficiency, environmental benefits and security benefits. It becomes a research hotspot in recent years in the international arena. Spallation target is a crucial and important component with great technical difficulty in this system. When nuclear wastes are transmuted in ADS, radioactive spallation products are produced constantly following spallation reactions of High energy and high-flux protons with the target. Therefore, it is necessary to study the problem of spallation target to evaluate the radiation hazards on the environment.In this paper, the nuclear number of long-life spallation products irradiated by protons for period of time,and the radiation hazards to the environment after the targets be taked out from ADS are researched. The results are as follows.Irradiated by protons for a period of time, the radiation doses of spallation targets are mainly distributed along the radial target of 10-30cm and 15cm away from the underside of target. And a dose-dependent with the increase of proton energy increases. Irradiated by the same energy proton, the dose of tungsten target is minimum, but the dose of lead-bismuth target and uranium target are six orders of magnitude. The dose of lead-bismuth target is similar to uranium target, but increases faster with the incident proton energy increasing. After packaged by water, the radiation dose of targets are decayed rapidly. It will be to basically stable 10 years later. Finally, the remaining radiation dose of lead-bismuth target is relatively large, tungsten target's is minimum.