Abstract:

The inhibitory effects of coal direct liquefaction residue (CDLR) on lignite pulverization were studied in a kilo rotary kiln during co-pyrolysis. Different CDLR to lignite quantity and particle size ratios were investigated in the study. The results showed that, with CDLR quantity ratio increased from 10% to 40% at 550℃, the co-pyrolysis char pulverization rate β was decreased from 7.55% to 1.98%, and the granulation rate λ was increased from 2.73% to 4.90%. Increasing CDLR quantity ratio effectively inhibited lignite pulverization and mixing granulation. Mixing 3-1 mm CDLR with 3-1 mm lignite reached the pulverization rate β of 2.82%, which is lower than the pulverization rate when mixing 6-3/13-6/25-13 mm CDLR with the same size lignite. Mixing 3-1 mm CDLR with 3-1 mm lignite reached the granulation rate λ of 24.99%, which was much higher than λ of mixing larger CDLR. Gray relational analysis indicated that the influence of CDLR size ratio on β and λ was greater than quantity ratio. A model of CDLR to lignite size and quantity ratio inhibiting lignite pulverization in rotary kiln during pyrolysis was constructed. The ratio factors affected pyrolysis along with other internal factors including strength of particle capturing, pore structure reinforcing and particle layer crossing behavior.

Key words: lignite pulverization, coal direct liquefaction residue, ratio factor, pyrolysis, granulation, particle size distribution, inhibitory effect, rotary kiln

摘要：

在公斤级回转窑中研究了共热解过程不同液化残渣与褐煤质量配比及粒度配比因素对抑制褐煤粉化效果的影响。结果表明：550℃共热解条件下，随液化残渣的添加比例由10%升至40%，共热解半焦的粉化率β由7.55%降至1.98%，造粒率λ由2.73%升至4.90%，液化残渣添加量的提升有效促进了对粉化的抑制及混合造粒；3～1 mm液化残渣与3～1 mm褐煤的共热解半焦β为2.82%，较与6～3/13～6/25～13 mm褐煤颗粒热解后的产物粉化率均低，而λ则达到24.99%，远高于其他粒度配比下的产物造粒率。灰色关联分析显示，粒度配比因素对β和λ的影响权重均大于质量配比因素。结合分析上述配比因素影响粉化抑制作用的内在诱因（强化粘连捕集颗粒行为，促进孔隙充填补强作用，颗粒穿层行为影响），形成了回转窑热解过程配比因素对抑制褐煤粉化的影响过程模型。

关键词: 褐煤粉化, 煤直接液化残渣, 配比因素, 热解, 造粒, 粒度分布, 抑制, 回转窑