Abstract: A process and apparatus for the production of pourable, directly compactable uranium dioxide powder by continuous precipitation of uranium peroxide from a stirred uranyl nitrate solution at a pH of 1-2.5 with hydrogen peroxide, calcining of the peroxide at 500.degree.-800.degree. C. and subsequent reduction at 550.degree.-750.degree. C. The precipitation solution contains 70-150 g/l of uranium and 0.80 g/l of ammonium nitrate and is treated with 15-20% aqueous hydrogen peroxide solution in the ratio of U:H.sub.2 O.sub.2 from 1:1.5 to 1:3 and there is led through the solution a mixture of ammonia and air having an air-ammonia volume ratio of 1:0.3-0.6.

Abstract: There is provided a process for the production of pourable, directly compactable uranium dioxide powder by continuous precipitation of uranium peroxide from a stirred uranyl nitrate solution at a pH of 1 - 2.5 with hydrogen peroxide, calcining of the peroxide at 500.degree.- 800.degree. C. and subsequent reduction at 550.degree.- 750.degree. C. The precipitation solution contains 70 - 150 g/l of uranium and 0.80 g/l of ammonium nitrate and is treated with 15 - 20% aqueous hydrogen peroxide solution in the ratio of U:H.sub.2 O.sub.2 from 1:1.5 to 1:3 and there is led through the solution a mixture of ammonia and air having an air-ammonia volume ratio of 1:0.3 - 0.6. An apparatus for carrying out the process is also described. SUBACKGROUND OF THE INVENTIONThe present invention is directed to a process and apparatus for the production of directly pressable (moldable) uranium dioxide powder from uranium peroxide (UO.sub.4.xH.sub.

Abstract: There is provided a process for working up and returning without lost waste into the process of casting kernels of uranium-thorium oxide by dissolving the wastes in a nitric acid-hydrofluoric acid mixture and neutralizing the strongly acid solution before the addition to the casting solution. The strong nitric acid solution is evaporated up to the appearance of nitrous gas, the residue diluted with water and this solution brought to a pH of 2.5 to 3.5 with ammonia at a temperature below 40.degree. C.

Abstract: There is provided a process for the solidification of radioactive boron containing aqueous solutions and suspensions containing more than 5% boric acid or a borate and more than 5% solids by addition of suitable additions in the correct sequence to form solid, transportable and storable blocks by using as the additive first 5 to 30 parts by weight of slaked lime and then 30-80 parts by weight of cement per 100 parts by weight of radioactive solution.