Containment analysis of the 9975 transportation package with multiple barriers

Vinson, D.W.

Savannah River Site (S.C.)

关键词: Safety Engineering;    Waste Transportation;    Containment Systems;    11 Nuclear Fuel Cycle And Fuel Materials;    Leaks;   

DOI  :  10.2172/750860
RP-ID  :  WSRC-TR-99-00476
RP-ID  :  AC09-96SR18500
RP-ID  :  750860

美国|英语

来源: UNT Digital Library

【 摘 要 】

A containment analysis has been performed for the scenario of non-routine transfer of a damaged 9975 package containing plutonium metal from K-area monitored storage to F-area on the Savannah River Site. A multiple barrier system with each barrier having a defined leakage rate of less than 1{times}10{sup {minus}3} cm{sup 3}/sec of air at Standard Temperature and Pressure was analyzed to determine the number of barriers needed to transport the package under normal transportation conditions to meet transportation requirements for containment. The barrier system was analyzed parametrically to achieve a composite system that met the federal requirements for the maximum permissible release rate given in Title 10 of the Code of Federal Regulations, Part 71. The multiple barrier system acts to retard the release of radioactivity. That is, a build-up in the radioactivity release rate occurs with time. For example, a system with three barriers (e.g., sealed plastic barrier) with a total free volume of 4,500 cm{sup 3} could be transported for a total time of up to approximately 10 days with a release rate within the permissible rate. Additional number of barriers, or volume of the barriers, or both, would extend to this period of time. For example, a system with seven barriers with a total free volume of 4,500 cm{sup 3} could be transported for up to 100 days. Plastic bags are one type of barrier used in movement of radioactive materials and capable of achieving a leak rate of 1{times}10{sup {minus}3} cm{sup 3}/sec of air at STP. Low-density polyethylene bags can withstand high temperature (up to 180 degrees C); a barrier thickness of 10 mils should be suitable for the barrier system. Additional requirements for barriers are listed in Section 4.2 of this report. Container testing per ANSI N14.5 is required to demonstrate leak rates for the individual barriers of less than 1{times}10{sup {minus}3} cm{sup 3}/sec.