Eh. Tusa et al., INDUSTRIAL-SCALE REMOVAL OF CESIUM WITH HEXACYANOFERRATE EXCHANGER - PROCESS REALIZATION AND TEST RUN, Nuclear technology, 107(3), 1994, pp. 279-284
At the Loviisa Nuclear Power Station (NPS) all liquid waste, i.e., spe
nt resins and evaporator concentrates, have been stored in a large tan
k storage facility. Dominating radionuclides in the evaporator concent
rates have been Cs-134 and Cs-137. By removing cesium from the waste,
purified liquid can be released within licensed release limits, and co
balt as a second dominating nuclide is left in a small waste volume on
the bottom of the tank. Since 1985, the use of inorganic hexacyanofer
rate-based materials for purification of cesium has been studied. A fu
ll-scale system for cesium removal, called the IVO-CsTreat System, was
constructed in 1990 to 1991. A method to produce the ion exchanger in
granular form in industrial scale was developed, and the facility to
produce it was constructed. The ion exchange material was produced in
1991, and the full-scale purification facility was commissioned at the
Loviisa NPS in October 1991. In the test run, 253 m3 of concentrate w
as purified between October 31, 1991 and June 11, 1992 with three ion
exchange columns, each with a volume of 8 l. A volume reduction factor
of over 10 000 was achieved as the ratio of liquid and ion exchanger
volume. The decontamination factor for cesium was approximately 2000.