Year
2001
File Attachment
33140.PDF327.01 KB
Abstract
It is advantageous to use liquid neutron shield for a spent fuel transportable storage cask, because of heat removal performance and manufacturing cost performance. In Japan, ethyleneglycol-water solution is used for HZ-75T and NH-25 transport casks which have been in operation for over 20 years. In the United States, there are many transport casks that use a water solution neutron shield. Also, a storage cask using an ethyleneglycol-water solution neutron shield with boron had been put to test use in the United States. Though the glycol-water solution as the neutron shield is satisfactorily practical as mentioned above, there are few reports concerning the change of its nature and the effect on the corrosion of cask materials under long time use. The transportable storage cask developed by OCL and NFT uses propyleneglycol-water solution that is comparable to ethyleneglycol-water solution in shielding ability and antifreezing performance. The propyleneglycol-water solution has been introduced because propyleneglycol is accepted as a food additive and consequently there is no environmental problem even if the solution leaks out under hypothetical accidents.