Investigation on water vapor effect on direct sulfation during wet-recycle oxy-coal combustion
Investigation on water vapor effect on direct sulfation during wet-recycle oxy-coal combustion
复制标题
湿法循环富氧煤燃烧过程中水蒸气对直接硫酸盐化的影响研究
DOI：
10.1016/j.apenergy.2013.03.022
复制
发表时间：
2013-08-01
期刊：
影响因子：
11.2
通讯作者：
Zhao, Changsui
中科院分区：
文献类型：
--
作者：
Duan, Lunbo;Jiang, Zhongxiao;Zhao, Changsui
在富氧煤燃烧过程中，由于CO2分压较高，石灰石脱硫可能由间接脱硫转变为直接脱硫。当湿烟气被回收时，水蒸气也将在炉内富集并影响脱硫反应。采用两种石灰石吸收剂研究了水蒸气对直接硫酸化反应的影响。分析了水汽浓度、温度和SO2浓度等参数。结果表明，水蒸气的存在下，直接硫酸化的动力学控制制度期间的影响可以忽略不计，而在扩散控制阶段的钙转化率提高。水蒸气的存在促进了硫酸化产物的固态扩散，并强化了产物层的烧结。颗粒中的空位沿着晶粒边界迁移并穿过晶格，导致质量反向流入孔中。水蒸气存在下的硫酸化产物的孔结构特征得到改善。(c)2013爱思唯尔有限公司保留所有权利。
During oxy-coal combustion process, limestone desulfurization may change from indirect into direct sulfation due to the high partial pressure of CO2. When the wet flue gas is recycled, the water vapor will also be enriched in the furnace and affect the desulfurization reactions. In the paper, two limestone sorbents were used to study the effect of water vapor on direct sulfation. Parameters including water vapor concentration, temperature and SO2 concentration were analyzed. Results show that the presence of water vapor has a negligible effect on the direct sulfation during the kinetically-controlled regime, while enhances the calcium conversion during the diffusion-controlled stage. The presence of water vapor promotes the solid-state diffusion of the sulfated product, and sintering of the product layer is intensified. The vacancies in the particles migrate along crystal grain boundaries and through the crystal lattice, resulting in a reverse flow of mass into the pores. The pore structure character of the products sulfated in the presence of water vapor is improved. (c) 2013 Elsevier Ltd. All rights reserved.