Sequestration of Flue Gas CO2 by Direct Gas-Solid Carbonation of Air Pollution Control System Residues
Sequestration of Flue Gas CO2 by Direct Gas-Solid Carbonation of Air Pollution Control System Residues
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DOI：
10.1021/es303713a
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发表时间：
2012-12-18
影响因子：
11.4
通讯作者：
Jiang, Jianguo
中科院分区：
文献类型：
--
作者：
Tian, Sicong;Jiang, Jianguo
采用不同的模拟烟气组合，研究了大气污染控制系统（APCr）残留物的直接气固碳酸化反应对CO2封存的影响。APCr的X射线衍射分析确定了CaClOH的存在，其最大理论CO2封存潜力为58.13克CO2/千克APCr的参考强度比法计算。反应机理服从一个快速的动力学控制的过程，然后由一个缓慢的产品层扩散控制的过程模型。温度是气固直接碳酸化反应的关键因素，对碳酸化转化率和CO2封存率均有显著影响。使用连续加热实验，APCr的最佳CO2封存温度为395 ℃。烟气中CO2含量对动力学控制过程的CO2封存率有一定的影响，但对最终的碳酸化转化率几乎没有影响。烟气中典型浓度的SO2不仅可以加速产物层扩散控制过程的碳化反应速率，而且可以提高最终的碳化转化率。在典型的烟道气中实现了68.6%和77.1%之间的最大碳酸化转化率。研究结果表明，气固直接碳酸化具有固碳速率快、抗杂质能力强、捕获转化率高等特点，为该技术在碳捕获与封存领域的应用提供了理论依据。
Direct gas-solid carbonation reactions of residues from an air pollution control system (APCr) were conducted using different combinations of simulated flue gas to study the impact on CO2 sequestration. X-ray diffraction analysis of APCr determined the existence of CaClOH, whose maximum theoretical CO2 sequestration potential of 58.13 g CO2/kg APCr was calculated by the reference intensity ratio method. The reaction mechanism obeyed a model of a fast kinetics-controlled process followed by a slow product layer diffusion-controlled process. Temperature is the key factor in direct gas-solid carbonation and had a notable influence on both the carbonation conversion and the CO2 sequestration rate. The optimal CO2 sequestrating temperature of 395 degrees C was easily obtained for APCr using a continuous heating experiment. CO2 content in the flue gas had a definite influence on the CO2 sequestration rate of the kinetics-controlled process, but almost no influence on the final carbonation conversion. Typical concentrations of SO2 in the flue gas could not only accelerate the carbonation reaction rate of the product layer diffusion-controlled process, but also could improve the final carbonation conversion. Maximum carbonation conversions of between 68.6% and 77.1% were achieved in a typical flue gas. Features of rapid CO2 sequestration rate, strong impurities resistance, and high capture conversion for direct gas-solid carbonation were proved in this study, which presents a theoretical foundation for the applied use of this encouraging technology on carbon capture and storage.