Absorption of CO2 from Flue Gas by K2CO3 and Na2CO3 Supported on Activated Carbon：Effects of SO2, NOx, and O2.

• Main Authors: Bor-Shyang Liao, 廖柏翔
• Other Authors: Shin-Min Shih
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/88121821411616899607

碩士 === 國立臺灣大學 === 化學工程學研究所 === 97 === A differential fixed-bed reactor was employed to study the effects of SO2, NOx, and O2 on the absorption of CO2 from flue gas by K2CO3 and Na2CO3 supported on activated carbon under low temperature(60℃) and humid conditions(70%RH). With the presence of water vapor, CO2, SO2, NOx, and O2, K2CO3 was converted to KHCO3, K2S2O5, K2SO4, KNO2, and KNO3, and Na2CO3 was converted to NaHCO3, Na2SO3, Na2SO4, NaNO2, and NaNO3. When K2CO3-IAC reacted with CO2(12.5%) and NOx(40-600ppm), the extent of carbonation decreased with increasing NOx concentration, but it was greater than that for the sorbent which reacted with CO2(12.5%) alone.When K2CO3-IAC reacted with CO2 and SO2(50-1000ppm), the extent of carbonation decreased with increasing SO2 concentration, but when the SO2 concentration was low(≦200ppm), it was greater than that for the sorbent which reacted with CO2 alone. When Na2CO3-IAC reacted with CO2 and SO2 or NOx, the extent of carbonation decreased with increasing SO2 or NOx concentration, but at low concentration of SO2(≦500ppm) or NOx(≦100ppm), the extent of carbonation was greater than that for the sorbent which reacted with CO2 alone. The carbonation of sorbents was not affected by the presence of O2(2.5~5.0%). If the concentrations of SO2 and NOx in the flue gas were reduced to values below 200 and 300 ppm, respectively, the extent of carbonation of a sorbent would not be less than that when both SO2 and NOx were absent. Under the same reaction conditions, the extent of carbonation of K2CO3-IAC was greater than that of Na2CO3-IAC. The reactivities of the sorbents decreased only a little after regeneration.