Calcination/Carbonation Cycles Using BOFS for CO2 Capture.
Date Issued
2011
Date
2011
Author(s)
Chu, Yi-Cheng
Abstract
A differential fixed-bed reactor was employed to measure the reactivities of basic oxygen furnace slag(BOFS), CaCO3, Ca(OH)2 sorbents towards CO2.
BOFS was carbonated at different temperatures(592oC-683oC) and different CO2 concentrations(12.5-100%) for 30min after calcination at 683oC in air for 10min. The carbonation rate increased with increasing CO2 concentration, but the CO2 concentration did not markedly affect the final fraction of carbonate; the optimum temperature was 638oC, and the highest final fraction of carbonate was 0.30. The final fraction of carbonate for calcium carbonate or calcium hydroxide under the same reaction conditions was much higher than that for BOFS, due to that part of calcium atoms in BOFS was combined with SiO2 and Al2O3 to form inert compounds.
The final fraction of carbonate for BOFS did not decrease with increasing calcination/carbonation cycle; the final fraction of carbonate was affected insignificantly by the CO2 concentration but significantly by carbonation temperature; the optimum temperature was 638oC. BOFS contains MgO, SiO2, Fe2O3, and Al2O3, and they may suppress the sintering of CaO and CaCO3, preventing the loss of CaO pore volume. The final fraction of carbonate for CaCO3 decreased with increasing calcination/carbonation cycle; the fraction was affected slightly by the carbonation temperature, but decreased with decreasing CO2 concentration when the concentration was below 50%. The decay of activity for Ca(OH)2 was the same as that for CaCO3. The addition of BOFS to CaCO3 could reduce the decay of sorbent activity.
Subjects
basic oxygen furnace slag
calcium hydroxide
calcium carbonate
carbon dioxide
carbonation
Type
thesis
File(s)![Thumbnail Image]()
Loading...
Name
ntu-100-R98524051-1.pdf
Size
23.54 KB
Format
Adobe PDF
Checksum
(MD5):2bc771b4507154ff9885f125059cfd0f