Study On Gasification Characteristics And Reaction Kinetics Of Huainan Coal

Because the high ash melting coal of huainan area can not be directly used in the entrained flow gasification by Liquid slag,the feasibility of high ash melting of Huainan coal being applied to entrained flow gasification by solid discharging was studied in the research.The three high ash melting point Huainan coal,ZB,ZD and ZX were selected as the research object.The gasification characteristics of Huainan coal were studied by using synchronous thermal analyzer,scanning electron microscope and reaction kinetics.The reaction kinetics of Huainan coal was analyzed by using homogeneous model,and the ash characteristics of Huainan coal were analyzed.Study on the gasification reactivity of different coal samples at different heating rates,it can be concluded that the change of heating rate has a significant influence on the gasification reactivity.The higher the heating rate,the higher R0.5 and the better the reactivity.Under the same heating rate,the R0.5 of ZD coal is the largest,and its reactivity is the best,followed by ZX coal.The R0.5 of ZB is the smallest and its gasification reactivity is the worst.The heating rate range from lOK/min to 20K/min,the lower the carbon conversion rate is at the corresponding temperature.The change of particle size also has certain effect on the gasification process.With the decrease of particle size,the reactivity index and weightlessness rate of samples gradually increase,but the degree of increase is different.At the same temperature,the finer granularity,coal carbon conversion rate is high,with the decrease of grain size of coal sample,the conversion rate of ZB curve to the left shift and ZD coal,the more fine particle size and reactivity is better,in different particle size difference curve the conversion rate of ZX coal gasification reaction that reduce carbon,particle size the influence of ZX on coal.Through the reaction kinetics calculation can be obtained using the homogeneous model for different coal samples,the higher heating rate,the apparent activation energy of lower reactivity is better;while at the same heating rate,for different coal samples,the smaller the particle size,the apparent activation energy is lower.The more fine particle size,the better reaction.This is in accordance with the conclusions obtained by the TG-DTG curves.By scanning electron microscopy observation of coal gasification slag in the microstructure at different temperatures.The melting state of three kinds of Huainan coal under high temperature,with the increase of temperature,the ash gradually from isolated loose granular gradually transformed into a close bond,three coal samples are from 1200℃ melting phenomenon is the obvious.Therefore,if the coal gasification technology is used in Huainan coal,the temperature control is suitable at about 1200℃.