4330711 Container combination for the transportation and storage of radioactive waste especially nuclear reactor fuel elements

4330711 Container combination for the transportation and storage of radioactive waste especially nuclear reactor fuel elements

to substantially increase the density of the final product. In instance of prolonged curing times, an accelerator chemical is added to the mixture to ...

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to substantially increase the density of the final product. In instance of prolonged curing times, an accelerator chemical is added to the mixture to speed curing. 4329248 PROCESS FOR THE TREATMENT OF HIGH LEVEL NUCLEAR WASTES A E Ringwood, Red Hill, Australia assigned to The Australian National University

For the transportation and storage of irradiated nuclear fuel elements there are needed combinations of inner and outer containers wherein the inner container should be usable for the storage of the fuel elements in correspondingly conceived fuel element storehouses without reloading, unnecessary waste of space and burden of weight on the storage support. This is obtained by a container combination in which (a) the bottom and the jacket of the outer container are so dimensioned in their thickness that they completely or preponderantly take care of the shielding function against gamma and neutron radiation, (b) the inner container is axially fixed in the outer container in such manner that the cover of the inner container and the cover of the outer container do not touch, (c) the radial position of the inner container in the outer container is fixed by a narrowing of the cross section of the inner space of the outer container proceeding downwardly to the bottom and (d) the outer wall of the inner container is made tight against the inner wall of the outer container through sealing elements.

A process for immobilizing high level waste (HLW) sludge containing aluminium and/or iron compounds which comprises the steps of: (1) mixing the sludge with a mixture of oxides, the oxides in said mixture and the relative proportions thereof being selected so as to form a mixture when heated at temperatures between 800 degrees and 1400 degrees C. crystallizes to produce a mineral assemblage containing (i) crystals capable of providing lattice sites in which the fission product and actinide elements of said HJ_,W sludge are securely bound, and (ii) crystals of at least one inert phase containing excess aluminium and/or iron, said crystals belonging to or possessing crystal structures closely related to crystals belonging to mineral classes which are resistant to leaching and alteration in appropriate geologic environments; and (2) heating and then cooling said mixture under reducing conditions so as to cause crystallization of the mixture to a mineral assemblage having the fission product and actinide elements of said HLW sludge incorporated as solid solutions within the crystals thereof, and the excess aluminium and/or iron crystallized in at least one inert phase. A mineral assemblage containing immobilized HLW sludge containing ah.tminium and/or iron compounds incorporated within the crystals thereof is also disclosed.

4331088 MANAGEMENT OF CHEMICAL TOXIC WASTES

4330711

L Gold, Two regimes of vertical shaft furnace operation can be employed to slag encapsulate hazardous chemical wastes. One of these is similar to a-method applicable to radioactive wastes, involving the pouring of hot molten siag from a Coal Reactor over the hazardous matter contained in a suitable designed crucible. The other method is especially ap-

CONTAINER COMBINATION FOR THE TRANSPORTATION AND STORAGE OF RADIOACTIVE WASTE ESPECIALLY NUCLEAR REACTOR FUEL ELEMENTS S, Ahner, R Christ, D Klein, P Srostlik, Rodenbach, West Germany ...

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