An experimental study of CaSO4 decomposition during coal pyrolysis
An experimental study of CaSO4 decomposition during coal pyrolysis
复制标题
煤热解过程中CaSO4分解的实验研究
DOI：
10.1016/j.fuel.2015.09.054
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发表时间：
2016-01-01
期刊：
影响因子：
7.4
通讯作者：
Chen, Leming
中科院分区：
文献类型：
--
作者：
Jia, Xin;Wang, Qinhui;Chen, Leming
将不同CaSO4比例的煤在固定床反应器中在500-800℃的温度范围内进行热解，研究煤热解过程中CaSO4分解的机理。结果表明，煤的存在极大地促进了CaSO4在高温下的分解，小龙滩褐煤热解过程中800℃分解了87%的CaSO4，这主要归因于固-固反应(2C+CaSO4→CaS+2CO(2))。还讨论了固有矿物、煤类型、保温时间和煤粒度对CaSO4分解的影响。通过比较原煤和脱矿煤的CaSO4分解率，可以得出结论，固有矿物质可以大大促进CaSO4在高温下的分解，热重分析（TGA）结果也证明了这一点。随着煤粒径的增大，CaSO4分解率呈现显着降低的趋势。本研究中使用的四种煤均能促进CaSO4分解，但四种煤的促进效果有所不同，这可能是由于煤固有矿物质和反应活性的差异所致。 (C) 2015 Elsevier Ltd. 保留所有权利。
Coal with different proportions of CaSO4 was pyrolyzed in a fixed-bed reactor in a temperature range of 500-800 degrees C to study the mechanism of CaSO4 decomposition during coal pyrolysis. The results showed that the presence of coal could greatly promote CaSO4 decomposition at high temperatures, and 87% CaSO4 was decomposed at 800 degrees C during Xiaolongtan lignite pyrolysis, which was mainly attributed to the solid-solid reaction (2C + CaSO4 -> CaS + 2CO(2)). The effects of inherent minerals, coal type, holding time and coal particle size on CaSO4 decomposition were also discussed. By comparing the CaSO4 decomposition rate between raw coal and demineralized coal, it could be concluded that the inherent minerals could greatly enhance CaSO4 decomposition at high temperatures, which was also be proved by the results of thermogravimetric analysis (TGA). CaSO4 decomposition rate presented a significant decrease with the increase of coal particle size. Four coals used in this study could all promote CaSO4 decomposition, but the promotion effect differed among those four coals which may be attributed to the difference in inherent minerals and the reactivity of coal. (C) 2015 Elsevier Ltd. All rights reserved.