Dissolution rate of Al2O3 of ash and slag from circulating fluidized bed boiler
WU Haibin
XUE Fangbin
CUI Yanwei
YANG Fengling
Abstract：In order to investigate the activity of fly ash and slag derived from the burning process of coal gangue and further extend their application,the chemical compositions of ash and slag from circulating fluidized bed boiler (CFB) was analyzed.The effect of burning temperature and particle size on the Al2 O3 dissolution of ash and slag was studied by 20％ hydrochloride acid (HCl) leaching and ultrafine activating.The results show that the contents of Al2O3 and SiO2 in the ash and slag are 25％ and 35％,respectively.In addition,the dissolution of Al2O3 decreases with the increase of burning temperature of coal gangue in CFB.The dissolution of Al2O3 exceedes 52％ when the burning temperature is 800-900 ℃.While the dissolution of Al2O3 decreases to 26％-40％ when the burning temperature increases up to 900 ℃.The dissolution of Al2O3 could be increased from 68％ to 93％ when the particle size decrease from 198 μm to 74 μm.
Keywords：circulating fluidized bed (CFB)slagacid leachingAl2O3dissolution
Publication Date：2017-01-01