Patent Number: 051805421
Section: claims

1. A container for material contaminated with a toxic substance or a radionuclide, wherein the improvement comprises, the container having a base, intersecting members at the base inside the container define a plurality of recesses therebetween, and absorbent cementitious material disposed in the recesses for absorbing liquid in the container. 2. A container as claimed in claim 1, wherein the cementitious material has a voidage between 40% and 75% by volume. 3. A container as claimed in claim 2, wherein the cementitious material comprises cement hydrated beyond 25%. 4. A container as claimed in claim 3, wherein the cementitious material comprises blocks disposed in respective recesses. 5. A container as claimed in claim 3, wherein the cementitious material comprises granules, the granules being between 5 mm and 70 mm. 6. A container as claimed in claim 1, the container being filled with compacted receptacles containing the contaminated material such that the liquid comprises any leakage from said compacted receptacles, and space in the container between the compacted receptacles being filled with a cementitious grout. 7. A container as claimed in claim 1, wherein the cementitious material is made by forming a cement slurry and a sodium bentonite clay slurry, subsequently mixing together the cement slurry and the clay slurry, and heating the resultant mixture at a temperature such as to remove capillary water from the mixture without to a substantial extend dehydrating any hydrated cement. 8. A container as claimed in claim 7, wherein the temperature is between 50.degree. C. and 100.degree. C. 9. A container as claimed in claim 8, wherein the mixed cement slurry and the clay slurry has a water/solids ratio of about 1.5/1. 10. A container as claimed in claim 9, wherein the clay slurry comprises about 5% (by weight) solution. 11. A container as claimed in claim 10, wherein the resultant mixture is poured into moulds before said heating to form rectangular blocks thereof to fit the recesses. 12. A container as claimed in claim 11, wherein the blocks are broken into granules before said heating, the granules being between 5 mm and 70 mm. 13. A container as claimed in claim 7, wherein the heating is followed by cooling of the resultant mixture and subsequent storage, until required in a said container, in an airtight environment.