Study On Flowability Of Coal Powders And Their Influencing Factors

In order to solve the problem of coal particle size fluctuation and slag blockage during Shell coal gasification in Sinopec Anqing Petrochemical Company,the samples such as graphite,filter cake,coal gangue,petroleum coke and six coal collected from different operation time in Shell coal gasification were studied.The influence of the type of powders,particle size on the flowability of coal powders was investigated,respectively.The relationship between surface electronegativity and flowability was studied by zeta-potential instrument.And the influence factors of water content are discussed by TGA.The flowability of YA,YH,XB,and other powder particles(graphite,filter cake,coal gangue and petroleum coke)were compared by means of the Carr index test and HR test.The particle morphology of different powders was observed by reflection microscope,and the sphericity of the particles was analyzed by using Image-pro plus image processing software.The results indicated the higher the sphericity of the powder,the better the flowability of the powder.Three particle sizes(middle diameter of 20?m,40?m and 60?m)of SH,YH,YA and petroleum coke were selected respectively,and the influence of particle size on the flowability of pulverized coal was investigated.The Carr index,HR index and Rosin-Rammler distribution indicated that the flowability of the coal powders was improved with the increase of particle size.The Carr index of 6 kinds of powders including SH,YH,3#TC,TC,YA and petroleum coke with different surface electronegativity was determined,and the fractal dimension was calculated.The results showed that the greater the surface electronegativity,the better the fluidity of the coal powders.The Carr index of YH coal with different water content was tested.Test results showed that the lower the water content,the greater the Carr index,the better the mobility of coal powders.