并列流化床煤气化炉内结块的研究

RESEARCH ON AGGLOMERATION IN A COAL GASIFIER WITH TWIN FLUIDIZED BEDS

对并列流化床煤气化炉内的结块进行了包括光学显微镜、热重（TGA／DTA／DTGA）、x射线分析（XRD）等多种方法的实验研究，分析了结快形成的过程机理，探讨了防止结块的相应措施。

The defluidization in a coal gasifier with twin fluidized beds isdue to the agglomeration of bed materials with cola ash. Optical microscope, x-raydiffraction (XRD), thermogravimetric analysis were carried out on the samples ofagglomerates. The results indicated the mechanism of agglomeration and defluidiza-tion processing. Because of high a1kali, alkaline earth elements and high sulfur con-tent in coal,the molten alkali and alkaline earth sulfates,which are likely to formlow-temperature eutectics,were formed on the char's surface,the molten ash matrixon the char can transfer to the surface of bed particls,and so, caused them to formagglomerates and defluidization as the result of random collision between the bedpartics coated with low-temperature compounds.Some discussion were also put forward on how to prevent the gasifier from agglomeration and defluidization in this paper.