Patent Number: 050733052
Section: abstract

A method of evacuating a container to a vacuum for use in treating radioactive wastes by placing the waste into the container, evacuating, sealing off and thereafter compressing the container, the method being characterized by placing the waste into the container, forming over the waste a filter layer of particulate material fulfilling one of the following requirements: and sealing off and compressing the container.. (1) A layer having a thickness of at least 5 mm and formed of a particulate material not smaller than 40 .mu.m to less than 105 .mu.m in mean particle size; PA0 (2) A layer having a thickness of D in mm and formed of a particulate material not smaller than 105 .mu.m to not greater than 210 .mu.m in mean particle size d in .mu.m, the thickness D and the mean particle size d having the relationship represented by: EQU D.gtoreq.(20/105).times.d-15;. and thereafter aspirating a gas through the filter layer from thereabove to evacuate the container and sealing off and compressing the container.