蒙东褐煤干燥特性实验研究

EXPERIMENTAL STUDY ON DRYING CHARACTERISTICS OF MENGDONG LIGNITE

研究了蒙东地区两种不同煤化程度褐煤的干燥过程,并对干燥至不同程度的褐煤进行分析.在干燥过程中不同煤化程度褐煤干燥速率变化趋势较为一致,煤化程度对干燥速率有一定的影响.煤化程度较低的乌拉盖褐煤其平均干燥速率较高,达到最大干燥速率的时间点较早.干燥过程改变了褐煤的微观结构,干燥后水分较低的褐煤其比表面积与原煤相比有所增加.随着干燥后水分的不断降低,褐煤中的含氧官能团表现为先减少后增加的趋势.与宝日希勒褐煤相比,乌拉盖褐煤中含氧官能团开始增加的时间点较早,更容易被氧化.

The drying processes of two types of lignite in Mengdong area with different coal rank were discussed in this paper, and lignite samples which were dried to different degree were analyzed as well. It was found that lignite samples with different coal rank had relatively identical drying rate variation trend, while the coal rank had certain impact on drying rate. The Wulagai lignite, which has lower coal rank, could he dried at relatively higher drying rate and reach the maximum drying rate earlier compared with Baorixile lignite. Moreover, drying process changed the micromeehanism of lignite, and the specific surface area of lignite which had lower moisture content after drying was bigger than raw coal＇ s. Along with the decrease of moisture content during drying process, the amount of oxygen functional groups in lignite declined firstly, and grew up then. Compared with Baorixile lignite, the amount of oxygen functional groups in Wulagai lignite increased earlier in drying process, which made it more easy to be oxidized.