原煤低温空气氧化法预脱硫影响因素的实验研究

Experimental Investigation of Effects on Pre-desulfurization Efficiency in the Low Temperature Air Oxidation Conditions

针对4种不同煤种的高硫煤,在固定床反应器中考察了原煤空气气氛低温氧化预脱硫过程的影响因素,包括煤种(总硫含量、形态硫分布和挥发分含量)和化学反应条件及传质条件(温度、停留时间和颗粒粒径等),处理前后的样品中硫形态根据GB/T215 1996分析,硫和碳的含量分析用LECOSC 444定碳定硫仪测试。实验结果表明,反应条件和煤种是影响硫析出的两类因素,煤中黄铁矿硫在400℃停留10min时,均可达到50%的脱除率,最高达到80 08%。对于高挥发分的煤,宜选择低的转化温度,较短的停留时间,并适当增加颗粒粒径,以控制高的碳和热量损失;对于低挥发分的煤,可增加反应温度和停留时间,相应降低颗粒粒径以增加硫析出率。400℃停留10min操作条件下,大同半焦中硫含量从原煤中的1 48%可降至0 62%,此时碳和热值损失分别为13 64%和16 22%。在500℃停留10min操作条件下,阳泉半焦中硫含量从原煤中的1 59%降至1 07%。

The tests of pre-desulfurization of high-sulfur Chinese coals lower temperature air oxidation method was presented. It aims at reducing sulfur to levels that make coal combustion environmentally acceptable and cost effective. In this process four Chinese coals from Yima, Datong, Xishan, and Yangquan were selected and tested in a fixed-bed. The variables of operational condition included temperature (300-500°C), solid resident time (10-60 min) and particle size (100 μm, 400 μm) in this process. The contents of sulfur and its form, volatile, calorific value, proximate analysis and ultimate analysis were determined before and after the desulfurization process according to Chinese standards. The experimental results showed that the coal types and experimental conditions are important factors in the process.