矿物质对SO_2释放的影响及钙的固硫机理  

Effects of Minerals on Sulfur Dioxide Release and Mechanism of Sulfur Retention by Calcium During Coal Combustion

作　　者：刘银河[1] 车得福[1] 徐通模[1] 

机构地区：[1]西安交通大学能源与动力工程学院,西安710049

出　　处：《西安交通大学学报》2005年第1期96-99,共4页Journal of Xi'an Jiaotong University

基　　金：国家重点基础研究发展规划资助项目 (G1 9990 2 2 2 1 0 );高等学校博士学科点专项科研基金资助项目 (2 0 0 2 0 6980 48)

摘　　要：为了开发高效燃烧脱硫技术,通过热质量/逸出气体分析实验研究了煤中矿物质对煤燃烧中SO2释放的影响以及钙的固硫机理.研究结果表明:脱灰后SO2的释放曲线由原煤的双峰变成单峰;Ca的添加能够促进煤中硫在低温下释放,但不同形态钙的固硫效果不同;脱灰煤中添加CaSO4后SO2的释放曲线又恢复为双峰,CaSO4没有固硫效果;添加CaCO3和CaO后SO2的生成会有明显减少,且CaO的固硫效果要比Ca CO3显著.基于这个实验结果,提出了程序升温燃烧条件下煤中的矿物质对SO2释放影响所遵循的吸附-解吸附机理,以及钙基固硫剂固硫所遵循的吸附-解吸附/氧化机理.An experiment was carried out to investigate effects of minerals on sulfur dioxide release and the mechanism of sulfur retention by calcium during temperature-programmed combustion of a high rank coal by TG/EGA method at 10°C/min. The major results are as follows. Demineralization causes the profiles of sulfur dioxide evolution to change from bimodality to single peak with two shoulders and increases the conversion of coal sulfur to sulfur dioxide. The absorption-desorption mechanism was developed to elucidate effects of minerals on sulfur release. Calcium can promote sulfur dioxide release in low temperature. Different calcium forms appear different effects on sulfur release. Calcium sulphate can serve as an inert component to change the sulfur dioxide evolution profiles without any sulfur retention. Calcium carbonate and calcium oxide can change sulfur release profile and reduce sulfur dioxide release. In addition, calcium oxide is more effective than calcium carbonate on sulfur retention. Calcium effect on sulfur dioxide reduction is governed by the present sulfur dioxide absorption-desorption/oxidation mechanism.

关 键 词：二氧化硫 脱灰 钙 煤燃烧 热重分析 

分 类 号：TQ534.9[化学工程—煤化学工程]