METHOD OF PURIFYING LIQUID RADIOACTIVE WASTES FROM CAESIUM RADIONUCLIDES Russian patent published in 2009 - IPC G21F9/12 

FIELD: physics.

SUBSTANCE: invention relates to the technology of purifying liquid radioactive wastes from caesium radionuclides and can be used for purifying acidic and neutral middle- and highly-active liquid radioactive wastes. The method involves sorption of caesium radionuclides on a ferrocyanide sorbent, alkalisation of the solution obtained after extraction of caesium radionuclides on the said ferrocyanide sorbent to pH of not less than 12, separation of the solution from the formed precipitate, its acidification to a pH value which is not optimal for sorption of caesium radionuclides at the sorbent which is selective towards caesium radionuclides, through which final purification of radioactive wastes from caesium radionuclides takes place. During purification of liquid radioactive wastes, alkalisation, filtration, acidification and final purification on a sorbent, which is selective towards caesium radionuclides, are repeated.

EFFECT: method allows for reducing activity of caesium radionuclides in liquid radioactive wastes by n·10⁶·times, and activity of highly-active liquid radioactive wastes (for example when operations are repeated twice) - by n·10⁹ times, which allows for converting middle- and highly-active liquid radioactive wastes into the category of clean content caesium radionuclides with concentration of these radionuclides lower than permissible concentration in water and allows for their repeated use or discharge into an open drainage system.

2 cl, 9 ex