FLUIDIZED-BED COMBUSTION OF COAL WITH LIME ADDITIVES - CATALYTIC SULFATION OF LIME WITH IRON COMPOUNDS AND COAL ASH
FLUIDIZED-BED COMBUSTION OF COAL WITH LIME ADDITIVES - CATALYTIC SULFATION OF LIME WITH IRON COMPOUNDS AND COAL ASH
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DOI：
10.1021/es60144a002
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发表时间：
1978-01-01
影响因子：
11.4
通讯作者：
STEINBERG, M
中科院分区：
文献类型：
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作者：
YANG, RT;SHEN, MS;STEINBERG, M
氧化铁（Fe 2 O3）在类似于煤的流化床燃烧中的化学环境中对CaO吸附SO2具有催化作用。与CaO物理混合的4重量%的Fe 2 O3使吸附（硫酸化）速率大约加倍。根据SO_3生成是反应的限速步骤的观点，讨论了催化反应的动力学机理。煤灰也催化硫酸化反应，并且Fe 2 O3似乎是这种催化作用中的活性组分。煤和流化床燃烧系统中存在的其他含铁化合物在燃烧气体中迅速氧化形成Fe 2 O3，并反过来催化硫酸化反应。近年来，流化床燃烧已被证实是一种有前途的多用途清洁煤燃烧技术（1-3）。影响该技术的关键因素之一是石灰添加剂对SO2的相对高的反应性，以在燃烧气体的环境中形成硫酸钙。过去已经做了大量的工作来确定在燃烧条件下变量的反应性的影响，例如SO2的温度和浓度（4，5），总压和快速变化的气氛（6，7），水蒸气和氧气分压（8，9），以及石灰石的通用因子（10）。
Iron oxide (Fe203) is catalytic to the sorption of S02 by CaO in a chemical environment similar to that in fluidized-bed combustion of coal. Four percent by weight of Fe203 physically mixed with CaO approximately doubles the sorption (sulfation) rate. The kinetic mechanisms of the catalytic re-action are discussed based on the view that S03 formation is the rate-limiting step. Coal ash also catalyzes the sulfation reaction, and Fe203 appears to be the active constituent in such catalytic effects. Other iron-containing compounds ex-istent in coal and fluidized-bed combustion systems are oxidized rapidly inthe combustion gases to form Fe203 and in turn catalyze the sulfation reaction.In recent years, fluidized-bed combustion has been recog-nized as a promising and versatile technology for clean com-bustion of coal (1-3). One of the crucial factors in effecting this technology is a relatively high reactivity of the lime ad-ditive toward S02 to form calcium sulfate in the environment of the combustion gases. A significant amount of work has been done in the past to determine the effects of the reactivity of the variables under combustion conditions, such as tem-perature and concentration of S02 (4, 5), total pressure and rapidly changing atmospheres (6, 7), water vapor and oxygen partial pressures (8, 9), and the generic factorof the limestone (10).