碳酸鉀和碳酸鈉負載於活性碳吸收煙道氣中二氧化碳之研究:二氧化硫之影響

Absorption of CO2 from Flue Gas by K2CO3and Na2CO3 supported on Activated Carbon: Effect of SO2

楊文育(Wen-Yu Yong)

指導教授 ： 施信民

國立臺灣大學/工學院/化學工程學研究所/碩士(2007年)

https://doi.org/10.6342/NTU.2007.03302

摘要

本研究使用微分床反應器探討二氧化硫濃度對碳酸鉀和碳酸鈉負載於活性碳上在低溫潤濕條件下吸收煙道氣中二氧化碳之影響。在水氣存在下二氧化碳和二氧化硫與碳酸鉀反應分別生成碳酸氫鉀以及亞硫酸氫鉀，與碳酸鈉反應分別生成碳酸氫鈉以及亞硫酸鈉。吸收劑與二氧化硫和二氧化碳一起反應時，二氧化硫濃度降低，硫酸化轉化率下降，而碳酸化轉化率上升，二氧化硫濃度降為500ppm以下時，碳酸鉀/活性碳吸收劑碳酸化轉化率與二氧化硫不存在時相同，而碳酸鈉/活性碳吸收劑在200ppm二氧化硫下，碳酸化轉化率仍受到二氧化硫存在的影響而降低。吸收劑反應轉化率隨著相對濕度的提高而增加，但二氧化碳濃度(12-50%)的影響不顯著。在相同反應條件下，碳酸鉀/活性碳吸收劑比碳酸鈉/活性碳吸收劑有較高的碳酸化轉化率，較適合用來吸收煙道氣中的二氧化碳。在60℃、70%相對溼度、12%二氧化碳和200-500ppm二氧化硫下，碳酸鉀/活性碳吸收劑吸收二氧化碳的轉化率可達83%。

關鍵字

碳酸鉀 ； 碳酸鈉 ； 二氧化碳 ； 二氧化硫 ； 吸收 ； 煙道氣

並列摘要

A differential fixed-bed reactor was employed to study the effect of SO2 on the absorption of CO2 from flue gas by K2CO3 and Na2CO3 supported on activated carbon under low temperature and humid conditions. With the presence of water vapor, CO2 and SO2 reacted with K2CO3 to form KHCO3 and KHSO3, and with Na2CO3 to form NaHCO3 and Na2SO3, respectively. As the SO2 concentration decreased, the extents of sulfation of sorbent, decreased and the extents of carbonation increased; the extent of carbonation of K2CO3-IAC was the same as that without the presence of SO2 , when the SO2 concentration was less than 500ppm, but the extent of carbonation of Na2CO3-IAC was still affected by the presence of SO2 when SO2 concentration was 200ppm. The reaction of sorbents was affected markedly by relative humidity and less pronouncedly by CO2 concentration. Under the same reaction conditions, K2CO3-IAC had higher extent of carbonation than Na2CO3-IAC. Thus, K2CO3-IAC is more suitable to be used as a sorbent to absorb CO2 from the flue gas. At 60℃, 70%RH, 12%CO2, and 200-500ppm SO2, the extent of carbonation of K2CO3-IAC was 83%.

並列關鍵字

K2CO3 ； Na2CO3 ； CO2 ； SO2

參考文獻

蔡志凡, ”碳酸鈉和碳酸鉀負載於活性碳吸收煙道氣中二氧化碳之研究”，碩士論文，國立台灣大學，台北，台灣 (2006)

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