Conference Paper

Radioactive wastewater treatment using selective ion exchangers

Dept. of Chem. & Environ. Process Eng., Budapest Univ. of Technol. & Econ., Budapest, Hungary
DOI: 10.1109/INREC.2010.5462565 Conference: Nuclear & Renewable Energy Conference (INREC), 2010 1st International
Source: IEEE Xplore

ABSTRACT

It is well known that in the Hungarian PWR-type nuclear power plant Paks the radioactive waste waters are collected in common tanks. These water streams contain radioactive isotopes in ultra-low concentration and inactive compounds as major components (borate 1.7 g/dm3, sodium-nitrate 0.4 g/dm3, sodium-hydroxide 0.16 g/dm3, and oxalate 0.25 g/dm3). These low salinity solutions were evaporated by adding sodium-hydroxide, until 400 g/dm3 salt content is reached. There is about 6000 m3 concentrated evaporator bottom residues in the tanks of the PWR. We have developed a complex technology for the selective separation of the long live radionuclides and for the partial recycle of boric acid from this evaporator bottom residue. A wastewater treatment system has been developed by using a cesium selective inorganic ion exchanger. The selective separation of cesium (137Cs, 134Cs) from high salt concentration and strongly alkaline evaporator bottom residue in Paks Nuclear Power Plant has a volume reduction factor about 1800-3500 at the value of the decontamination factor DF > 100, for the samples of four tanks of the Hungarian PWR Paks.

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Available from: Gyorgy Pátzay, Apr 29, 2015
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    • "may carry out (ATSDR, 2004). Therefore, the elimination and disconnection of 137 Cs from radioactive waste solution in economical and safe methods has been paid serious solicitude. Different methods have been applied to remove 137 Cs from aqueous solution such as precipitation (Rogers et. al., 2012), extraction (Inoue et. al., 2014), ion exchange (Pátzay et. al., 2009), bioaccumulation (Rowan, 2013), electric-field assisted (Sviridov et. al., 2012) techniques and adsorption (Yavari et. al., 2011). Among them, adsorption technique is one of the most commonly and efficacious methods in radioactive waste treatment and it represented the green chemistry direction to reduce the use of toxic and carcinogeni"

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