Chemical Absorptipn of Carbon Dioxide in Glue Gas From Municipal Solid Waste Incinerators

• Main Authors: Li, Wen-Yang, 李文揚
• Other Authors: 李慧梅
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/82590757244370573638

碩士 === 國立臺灣大學 === 環境工程學研究所 === 91 === Greenhouse effect has great Impact on global climate. In regard of greenhouse gases emission, carbon dioxide is the most discharging one. In Taiwan, carbon dioxide approximately accounts for 78% of the total emission of greenhouse gases. Although solid waste department in Taiwan only accounts for 7.6% of emissions of total greenhouse gases, some new incinerators have been built in recent years. These incinerators contributed also to emission of carbon dioxide.Therefor it is necessary to take measures to reduce carbon dioxide emission from incinerators. Chemical absorption method for reducing acid gases in flue gas is a common technology in views of operation and cost. This study continues Liao’s study (2002) which investigated reduction of carbon dioxide from incinerator. In this study, we used three absorbents, monoethanolamine (MEA), sodium hydroxide (NaOH) and ammonia (NH3) and changed inlet-gas temperature and absorbent concentration to examine the effect of recycling on absorption efficiency. We also used theorfical model to predict the procees of gas-liquid transfer. The experimental results show that inlet-gas temperature didn’t affect absorption and absorption time. But increasing concentration can increase absorption efficiency and the number of cycles for recycling absorption. The results also indicate that absorption capacity of ammonia is the hightest (0.45~0.57 kg-CO2/kg-NH3), sodium hydroxide is medium (0.25~0.28kg-CO2/kg-NaOH) and monoethanolamine is the lowest (0.20~0.22 kg-CO2/kg-MEA). According to the results removal efficiency of carbon dioxide by ammonia is the best and it is also the best for absorption capacity, cost, and emission of waste water. Sodium hydroxide is medium and monoethanolamine is the worst. Model calculations indicate that mass-transfer coefficients between carbon dioxide and absorbent in packed column range from 1.23×10-4 to 8.80×10-4 (m/s), enhancement factor is between 4 and 8. Mass-transfer coefficient and enhancement factor changed with temperature and absorbent concentration.