Li Bin, Du Xia-ru, Li Qing-feng, Zhang Jian-min, Wang Yang
Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, China.
Huan Jing Ke Xue. 2004 Jan;25(1):149-53.
In this study, the effect of acid treatment of Yima coal on predesulfurization during pyrolysis and partial gasification were investigated. The coal was treated with HCl, HCl-HF and HCl-HNO3 solution, in which different minerals were eliminated. The whole process could be divided into pyrolysis and partial gasification. In pyrolysis process, the evolution of H2S and COS show two peaks, which were 450 degrees C and 600 degrees C respectively. At high temperature, the amount of H2S evolution from acid treated coal was markedly increased compared to the raw coal through the elimination of minerals. In the case of HCl-HNO3 treated sample, the H2S evolution in the low temperature region, below 500 degrees C, was reduced and the COS evolution in higher temperature region, above 500 degrees C, was increased by the chemical oxidation. In the partial gasification process, the sulfide sulfur removal of acid treated coal char was increased, reached about 100% at 800 degrees C. The maximum of total and sulfide sulfur removal of parent coal char were 46.39% and 52.97% at 700 degrees C. Compared to acid treated coal char, the effect of alkaline minerals for fixing sulfur was strengthened with increasing the temperature. The organic sulfur of acid treated coal char was released with carbon gasification, and the value could be constant.
本研究考察了酸处理对义马煤热解和部分气化过程中预脱硫的影响。用HCl、HCl-HF和HCl-HNO₃溶液处理煤，以去除其中不同的矿物质。整个过程可分为热解和部分气化。在热解过程中，H₂S和COS的析出呈现两个峰值，分别为450℃和600℃。高温下，通过去除矿物质，酸处理煤析出的H₂S量比原煤显著增加。对于HCl-HNO₃处理的样品，通过化学氧化作用，在500℃以下的低温区域H₂S析出减少，在500℃以上的高温区域COS析出增加。在部分气化过程中，酸处理煤焦的硫化物硫去除率提高，在800℃时达到约100%。原煤焦的总硫和硫化物硫去除率在700℃时分别达到最大值46.39%和52.97%。与酸处理煤焦相比，随着温度升高，碱性矿物质固硫作用增强。酸处理煤焦中的有机硫随着碳气化而释放，其值可以保持恒定。
