TY - GEN
T1 - Development of an In-Situ Mixed Iron Oxide (IS-MIO) process for the removal of strontium and actinides from alkaline tank waste
AU - Pereira, C.
AU - Arafat, H. A.
AU - Gelis, A. V.
AU - Aase, S. B.
AU - Vandegrift, G. F.
PY - 2004
Y1 - 2004
N2 - An In-situ Mixed Iron Oxide or IS-MIO process is being evaluated for removal of radioactive strontium (Sr)and actinides from alkaline tank wastes at the Savannah River Site. In the IS-MIO process, a solution of iron (II) sulfate and iron (111) nitrate, is added to highly alkaline tank waste containing radioactive strontium and actinides. An iron (Fe) precipitate is formed immediately upon contact with the waste solution. This precipitate captures the radionuclides of interest in the waste by occlusion, co-precipitation, or a combination of both processes. The solids remain suspended in the solution forming a slurry that can be separated from the treated waste by filtration. The effectiveness of the ISMIO in-tank process depends on the effectiveness of the decontamination. Iron oxide has been shown effective in removing Sr and actinides from waste at the laboratory scale. In a tank process, effective mixing is required to rapidly distribute the precipitated iron oxides throughout the volume upon addition of the Fe solution to the tank waste. In this paper we examined the effectiveness of IS-MIO in removing Sr, plutonium (Pu), uranium (U), neptunium (Np), and americium (Am) from a simulated tank waste and the effect of mixing intensity and residence time on the precipitates that are formed. Decontamination Factors (DF) were measured as a function of time, Fe concentration, and temperature. The effect of mixing intensity and duration on the particle size distribution, morphology, and uniformity of the suspension are also described.
AB - An In-situ Mixed Iron Oxide or IS-MIO process is being evaluated for removal of radioactive strontium (Sr)and actinides from alkaline tank wastes at the Savannah River Site. In the IS-MIO process, a solution of iron (II) sulfate and iron (111) nitrate, is added to highly alkaline tank waste containing radioactive strontium and actinides. An iron (Fe) precipitate is formed immediately upon contact with the waste solution. This precipitate captures the radionuclides of interest in the waste by occlusion, co-precipitation, or a combination of both processes. The solids remain suspended in the solution forming a slurry that can be separated from the treated waste by filtration. The effectiveness of the ISMIO in-tank process depends on the effectiveness of the decontamination. Iron oxide has been shown effective in removing Sr and actinides from waste at the laboratory scale. In a tank process, effective mixing is required to rapidly distribute the precipitated iron oxides throughout the volume upon addition of the Fe solution to the tank waste. In this paper we examined the effectiveness of IS-MIO in removing Sr, plutonium (Pu), uranium (U), neptunium (Np), and americium (Am) from a simulated tank waste and the effect of mixing intensity and residence time on the precipitates that are formed. Decontamination Factors (DF) were measured as a function of time, Fe concentration, and temperature. The effect of mixing intensity and duration on the particle size distribution, morphology, and uniformity of the suspension are also described.
UR - http://www.scopus.com/inward/record.url?scp=4143115585&partnerID=8YFLogxK
M3 - Conference contribution
AN - SCOPUS:4143115585
SN - 0816909423
SN - 9780816909421
T3 - 2004 AIChE Spring National Meeting, Conference Proceedings
SP - 2604
EP - 2617
BT - 2004 AIChE Spring National Meeting, Conference Proceedings
T2 - 2004 AIChE Spring National Meeting, Conference Proceedings
Y2 - 25 April 2004 through 29 April 2004
ER -