褐煤同参数液态水热和蒸汽水热提质对比

通过改变煤水布置方式,分别对霍林河褐煤进行同参数下液态水热提质和蒸汽水热提质处理,考察不同水热提质方法对褐煤理化结构和水分复吸特性的影响。实验结果表明,蒸汽水热处理与液态水热处理的脱水、提质效果相似,但前者能有效降低有机组分损失,提高褐煤产率。随温度升高,两种水热提质煤孔隙结构均呈现先增长后减小趋势,但蒸汽水热提质煤孔结构在250℃以后才发生明显下降。随温度升高,水分形态对含氧官能团脱除的影响逐渐减弱,但液态水热处理对褐煤中脂肪族等有机结构降解作用更强。在300~350℃,由于含氧官能团的脱除和孔结构收缩,两种水热处理均对褐煤水分复吸行为有显著抑制作用,但采用蒸汽水热处理能有效降低固体损失,工程应用前景更好。

Comparative of liquid and vapor hydrothermal upgrading of lignite in the same condition

Liquid and vapor hydrothermal upgrading of Huolinhe lignite were carried out by changing the placing method of coal and water to study the effect of hydrothermal methods on the physicochemical structure and moisture reabsorption characteristics of lignite.The experiment results showed that the dewatering and upgrading performance of vapor hydrothermal treatment was similar to that of liquid hydrothermal treatment,but the vapor hydrothermal treatment could effectively reduce the loss of organic components and increase the yield of lignite.With the increase of treatment temperature,the pore structure of the two kinds of hydrothermal upgraded coals firstly increased and then decreased,but the pore structure of vapor upgraded coals started to decrease significantly until 250 ℃.The effect of the phase of water on the removal of oxygen containing functional groups was gradually weakened as the temperature increased,whereas the aliphatic compounds were degraded more remarkable during liquid hydrothermal upgrading.When the temperature ranged from 300 ℃ to 350 ℃,the moisture reabsorption characteristics of the two kinds of hydrothermal upgraded coals were obviously restrained because of the removal of oxygen containing functional groups and the shrink of pore structure.However,the engineering application prospect of vapor hydrothermal upgrading is better in consideration of its higher yield of solid product.