TY - JOUR
T1 - The role of environmental conditions on the carbonation of an alkali-activated cementitious waste form
AU - Zhang, Peng
AU - Lewis, Janelle Branch
AU - Klein-BenDavid, Ofra
AU - Garrabrants, Andrew C.
AU - Delapp, Rossane
AU - van der Sloot, Hans A.
AU - Kosson, David S.
N1 - Publisher Copyright:
© 2021
PY - 2022/1/1
Y1 - 2022/1/1
N2 - Cast Stone is a cementitious waste form being considered for the solidification of low activity waste at the DOE Hanford Site. Under near-surface disposal conditions in an arid environment, Cast Stone is subject to drying and carbonation which may impact retention of waste constituents. This study investigates the effects of environmental CO2 concentration and relative humidity (RH) on the carbonation of Cast Stone. The rate of carbonation front ingress and the extent of carbonation reaction were characterized for samples aged up to 48 weeks at three RH levels and two CO2 concentrations. While the 68% RH environment allowed the greatest reaction extent, the 15% RH environment yielded the deepest carbonation front ingress. At 68% RH, there was a linear relationship between the ingress rate and CO2 concentration. Carbonation reactions increased the drying rate of Cast Stone. Redistribution of sodium toward the wetting front was observed under drying and carbonation conditions.
AB - Cast Stone is a cementitious waste form being considered for the solidification of low activity waste at the DOE Hanford Site. Under near-surface disposal conditions in an arid environment, Cast Stone is subject to drying and carbonation which may impact retention of waste constituents. This study investigates the effects of environmental CO2 concentration and relative humidity (RH) on the carbonation of Cast Stone. The rate of carbonation front ingress and the extent of carbonation reaction were characterized for samples aged up to 48 weeks at three RH levels and two CO2 concentrations. While the 68% RH environment allowed the greatest reaction extent, the 15% RH environment yielded the deepest carbonation front ingress. At 68% RH, there was a linear relationship between the ingress rate and CO2 concentration. Carbonation reactions increased the drying rate of Cast Stone. Redistribution of sodium toward the wetting front was observed under drying and carbonation conditions.
KW - Alkali activated cement
KW - Carbonation
KW - Drying
KW - Grout
KW - Radioactive waste
KW - Relative humidity
UR - http://www.scopus.com/inward/record.url?scp=85118484499&partnerID=8YFLogxK
U2 - 10.1016/j.cemconres.2021.106645
DO - 10.1016/j.cemconres.2021.106645
M3 - Article
AN - SCOPUS:85118484499
SN - 0008-8846
VL - 151
JO - Cement and Concrete Research
JF - Cement and Concrete Research
M1 - 106645
ER -