常压程序升温还原-质谱法研究遵义煤在热解过程中硫的变迁行为

Sulfur transformation during pyrolysis of Zunyi coal by atmosphere pressure-temperature programmed reduction-mass spectrum

选取遵义(ZY)原煤及其热解半焦,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了温度和气氛对热解过程中硫变迁行为的影响。结果表明,对于ZY煤而言,黄铁矿和不稳定有机硫除在氮气气氛下500℃时热解不能全部分解外,在其他条件下热解时都可以分解。1%氧气对ZY煤中稳定的有机硫的分解有很强的促进作用,不仅可以脱除稳定的有机硫,还可以使更稳定的有机硫断裂生成次稳定的有机硫,在随后的AP-TPR-MS实验过程中,这部分硫在较低的温度下逸出。合成气和1%氧气在700℃时与氢气有着相同的脱硫效果。

The effects of temperatures and atmospheres on sulfur transformation during pyrolysis of Zunyi （ZY） raw coal and its chars were investigated by AP-TPR-MS combined with chemical analysis. The results show that stable organic sulfur is the main sulfur form in ZY coal. Pyrite can be removed under all the atmospheres in the tests, except for nitrogen at 500 ℃. 1% O2-N2 atmosphere has strong reactivity to remove the stable organic sulfur in ZY coal, especially at 700 ℃. Under 1% O2-N2 atmosphere, not only a part of stable organic sulfurs can be decomposed, but also more stable organic sulfur-containing structure can be broken down into less stable one. Syngas and 1% O2-N2 atmospheres have almost the same effect as hydrogen on sulfur transformation at 700 ℃.