Patent Number: 042833671
Section: abstract

A method of and apparatus for separating krypton from radioactive waste gs which become free during the chemical dissolution of burnt-off fuel particles and contain krypton and xenon. Simultaneously with the core fuel particles conveyed to the chemical dissolution, such quantity of chemically inactive carrier gas intermixable with the waste gases is added to the substances bringing about the chemical dissolution that after purification of the waste gas mixture from gas components such as oxygen, carbon dioxide, nitrous oxide, hydrocarbons and water steam and after subsequent cooling of the waste gas mixture to the boiling temperature of the liquid nitrogen, the quantity of xenon contained in the waste gas mixture is quantitatively precipitated in solid form. Thereupon the waste gas mixture is by means of liquid nitrogen, while simultaneously increasing the pressure, cooled to such an extent that krypton is precipitated. The apparatus for practicing the above mentioned method is characterized primarily in that a chamber communicating with a supply for the fuel particles and for carrier gas and equipped with a conveying device is provided with a connection to a dissolver. In a waste gas conduit connected to the dissolver are inserted in series a waste gas purifier, a nitrogen cooled container for separating solid xenon, a compressor for subjecting the waste gas mixture to a pressure of approximately 4 bars, and a nitrogen cooled separator for krypton with following shut-off device.