在自行设计的有机玻璃补气料仓系统上对宽筛分粒煤下料特性进行了实验研究。结果表明,料仓出口直径、粒煤粒径和外水分对宽筛分粒煤在补气料仓中的下料特性有显著影响。宽筛分粒煤的下料流率随料仓出口直径的增大而增加,但增加量随着补气量的增加而减小。增加宽筛分粒煤的平均粒径使料仓出口有效尺寸减小,导致物料下料流率减小。增加宽筛分粒煤的外水分,致使下料过程中细颗粒煤粉发生团聚,物料流动性变差,且极易结拱,下料流率降低。为保证宽筛分粒煤在补气料仓中稳定连续下料,其外水分存在一个极限值,此极限值与宽筛分粒煤的粒径、煤种及料仓结构有关,在补气料仓出口直径为35 mm的实验系统中,0~2.50 mm、0~3.86 mm及0~5.44 mm宽筛分粒煤的极限外水分分别为5.30%、7.50%、7.60%。
The flow characteristics of granular coal with wide size distribution from an aeration plexiglass silo were investigated.The results showed that outlet diameter of the silo,coal particle size and moisture content had significant effects on discharge characteristics of granular coal with wide size distribution from aeration silo.The discharge rate of granular coal with wide size distribution increased with increasing outlet diameter,but the increase decreased with increasing gas flow rate.Effective size of outlet diameter decreased with increasing average particle size of granular coal with wide size distribution,which resulted in decreased discharge rate.Increasing moisture content of granular coal with wide size distribution would lead to agglomeration of the fine pulverized coal.During the discharging process of high moisture content granular coal with wide size distribution,an arch could be easily formed,and discharge rate decreased.In order to ensure stable and continuous discharge of granular coal with wide size distribution in the aeration silo,there existed a limiting moisture content which was affected by particle size of granular coal,coal type and silo structure.In this system,outlet diameter of aeration silo was 35 mm,limiting moisture contents of the 0—2.50 mm,0—3.86 mm and 0—5.44 mm granular coal were 5.30%、7.50% and 7.60% respectively.