流化床条件下煤的一次爆裂特性的实验研究

EXPERIMENTAL STUDY ON PRIMARY FRAGMENTATION OF COALS IN FLUIDIZED BED

流化床锅炉中煤的爆裂特性对锅炉运行的炉内传热、碳转化率和细微颗粒的排放等许多方面有重要影响。本文在一台小型常压流化床反应器中研究了一种烟煤的一次爆裂特性。对此烟煤不同宏观煤岩类型 (亮煤和暗煤 )的一次爆裂特性进行了比较研究。实验发现颗粒的一次爆裂率和爆裂程度很大程度上取决于颗粒粒径以及煤颗粒的组成 ,亮煤具有与暗煤不同的一次爆裂特性 ,同一粒径的煤颗粒爆裂后形成具有一定特点的粒径分布。针对不同煤岩类型的爆裂实验研究了煤颗粒的显微组分、矿物质含量、挥发分含量、硬度及其孔隙性质和热解中爆裂特性之间的联系。

The behavior of primary fragmentation in fluidized bed boilers shows some important effects on boiler operation including heat transfer, efficiency of carbon conversion and emission of fines The primary fragmentation behavior of different lithotypes of the bituminous coal (clarain and durain) was studied and compared with each other in an atmosphericd fluidized bed Particle size distribution curves are presented The extent of fragmentation is strongly dependent on the size and chemical composition, and related to the lithotypes of the coal It was found that the primary fragmentation behaviors of clarain and durain are different and there are some special size distributions after fragmentation The experiments of different lithotypes are aimed at finding a relationship between macerals, mineral matter, volatile content, hardness and pore properties of the parent coal particles, and the primary fragmentation during devolatilization