无烟粉煤制炭化型煤的炭化黏结特性研究
Study on carbonized binding features of carbonized briquette prepared with anthracite powder
-
摘要: 基于自制加压炭化装置和热重(TG)、X射线衍射(XRD)、扫描电镜(SEM)分析等方案,对以煤改性黏结剂、无烟粉煤制备的炭化型煤的结构和黏结特性进行研究。结果表明:型煤在炭化过程中出现2个明显的收缩阶段,第一个收缩阶段(室温~480℃),收缩量为3.2 mm;第二个收缩阶段(650~900℃),收缩量为1.7 mm。黏结剂和煤粒的共同作用引起型煤失重变化、孔结构变化和体积收缩。随着炭化温度的升高,500℃时型煤的孔容和比表面积达到最大,分别为0.871 1 cm~3/g和30.42 m~2/g。炭化型煤的芳香结构整体向有序化方向发展。黏结剂软化形成凝胶覆盖在煤粒表面,500℃以后缩聚、固化于无烟煤粒间。700℃以后固化的黏结剂与粉煤进一步缩聚形成由C—C键连接的叶片状结构,型煤抗压强度提高到14.2 MPa。Abstract: based on a self made pressuized caroonized device and thermogravinetry.v- ray diffraction.scaning elecron microscope analysis and other plan.a study was conducted on the structure and biding featues of the coal modfed binder and fine anthracite prepared caroonized brioute The resuits showed that there would be two obvious shrinkage stages during thecabonization proc.ss of the briquete.At the first shrinkage stage( indoor temperature to 480 ℃C,the shrinkage voumewas 3. 2 m.At thesecond shrinlage stage( 650-00 C),theshrinkage volume was 1.7 mm.The jint effect of the binder and ceal paricles would cause a weightlossvariation.pore structure variaton and volume shrinkage of the briquete . with the caroonization temperature inreased when the temperature reached at 501 ℃.the porevolume and spetific suriace area of the briquette would reach the max value and would be 0.871 1 cn3l g and3.0.42 m 2 g individual The aromaticstvcture of the cabonized briquette would be entirely develoed in an ordering drecfon.The gelation formed with ider sofening would cover on the suraces of th cal paricles andwould polymnerze and consolidate between the anthracte paricles aner the tenperture reached at 500 "C.Afer the temperature reached at 70 C.theconsaoliated bnder and coal powder would be further polymerzed to form lea structure with C一C ke linkage and the comprssive strength of the briquete would be increased to 142 MPa.