实验选取六枝(LZ)原煤及其在固定床热解所得半焦,采用常压程序升温还原-质谱法(AP—TPR—MS)与化学法相结合考察温度和气氛对固定床热解过程中硫变迁行为的影响。对于LZ煤而言,经氮气气氛500℃热解后,只能使煤中部分不稳定有机硫分解,黄铁矿硫却不能分解;而经氮气气氛700℃热解后可以使不稳定有机硫和黄铁矿硫全部分解。合成气气氛在500℃以前煤中的不稳定有机硫和黄铁矿硫就能全部分解,且随着温度的升高,合成气表现出与氢气相近的脱硫活性。1.0%O2-N2对于六枝煤并没有明显的脱硫效果,这与氮气气氛相差不大。
The effects of temperatures and atmospheres on the sulfur transformation during pyrolysis of Liuzhi (LZ) raw coal and the chars (prepared by pyrolysis in a fixed bed reactor) were investigated by AP-TPR-MS combined with chemical analysis. The results show that only a small part of unstable organic sulfur in LZ coal can be removed by pyrolysis in the fixed bed reactor at 500 ℃ under N2 atmosphere, but pyrite and unstable organic sulfur can be completely removed at 700 ℃ under N2 atmosphere, and those sulfurs can also be removed at 500℃ under syngas atmosphere. The higher the temperatures, the greater the reactivity of sulfurs with syngas atmosphere, which is very similar to that under H2 atmosphere. However, the sulfur removal is less under 1.0% O2-N2 atmosphere like that under N2 atmosphere.