【摘要】 为拓宽气固流化床干法选煤加重质的粒级范围,分别配制了B-A型磁铁矿粉和B-A型粉煤,并按一定比例将两者混合作为宽粒级加重质,研究了其流化特性及分选性能,结果表明:由于A类颗粒中较细及密度较小物料的影响,随着床高增大,床层密度逐渐降低,且密度分布标准偏差较大,为0.060 1 g/cm3.在合理的工艺及操作参数条件下,处于循环状态的0.3~0.074 mm级磁铁矿粉和1~0.15 mm级粉煤在流化床中分布均匀,床层密度均匀稳定,宽粒级加重质的流化性能良好,用于分选50~6 mm煤炭,分选密度为1.61 g/cm3时,可能偏差(E值)为0.06 g/cm3,分选精度较高.更多还原

【Abstract】 To expand the suitable size range of medium solids used in gas-solids fluidized beds for dry separation of coal,a type B-A magnetite powder and type B-A fine coal with a specific size distribution were mixed at a specific ratio of weight.The fluidization characteristics and separation performances of the mixture with a wide size range were studied.The results show that in the presence of particles with smaller size or lower density in group A powders,the bed density decreases gradually with the increasing of bed height with a high density standard deviation value of 0.060 1 g/cm3.Both magnetite powder with 0.3-0.074 mm size and fine coal with 1-0.15 mm size distribute uniformly in a commercial gas-solids fluidized bed with uniform and stable density,and the fluidization performances of recycled medium solids with a wide size range of 1-0.074 mm are very good under suitable technical and operating parameters.The commercial fluidized bed using medium solids with a wide size range of 1-0.074 mm can efficiently separate coal of 50-6 mm size with a low probable error E value of 0.06 g/cm3 at a separating density of 1.61 g/cm3.更多还原