阳泉高硫无烟煤热化学法预脱硫的试验考察

INVESTIGATION ON SULFUR TRANSFORMATION OF YANGQUAN ANTHRACITE WITH VARIOUS GAS ATMOSPHERES

以阳泉高硫无烟煤为考察对象 ,在马福炉及Φ 5 0mm流化床中考察其热化学条件下的预脱硫效果 ,以期为粉煤电站提供洁净煤气及低硫半焦 ,控制硫排放污染。本试验中采用的热化学法包括低温氧化、高温热解及部分气化以及煤、甲烷共气化。研究结果表明 :由于阳泉无烟煤变质程度高 ,硫分中有机硫含量高且主要是稳定的噻吩硫 ,采用常规高温热解部分气化方法较难脱出 ,处理后挥发分损失较大 ,高温操作又造成了较高能耗 ;采用低温氧化法可使原煤挥发分大部分保留 ,满足电站对入炉原料的要求 ,煤样处理后失重小 ,硫分脱出率较高 ,但失碳较多 ,热值损失较大 ;高硫煤、甲烷共气化法可利用过程提供的高氢气氛条件促进煤中硫分析出 ,处理后煤样热值损失较小 ,硫分脱出效率较高。

The investigation on sulfur transformation of Yangquan anthracite was carried out in a lab-scale fluidized bed reactor by thermo-chemical treatment including low temperature oxidation (LTO), high temperature pyrolysis and partial gasification (HTPG), and co-gasification with methane (CGM). It is found that sulfur in Yangquan anthracite can be quickly and selectively released into coal gas in the early stage of HTPG process and then released at the same rate of carbon in coal. Thus, char with lower sulfur and higher carbon recovery can be obtained at lower temperature and shorter residence time. Compared with HTPG method, the char with lower sulfur content can be obtained by LTO method. However, char with lower heat value was obtained although its weight and volatile matter content changed little. The newly-developed pre-desulfurization process of CGM can utilize coalbed methane to ensure a hydrogen-rich environment in gasifier to promote the coal sulfur release and meanwhile decrease heat loss of coal treated. And its sulfur release rate was greater than that of HTPG and LTO methods at the same carbon conversion rate. The futher work will be conducted to optimize operation conditions of CGM method.