Experimental Research On Char Structure And Hydrogasification Reactivity Of Shenfu Coal

The hydrogasification of Shenfu coal,divided into coal pyrolysis and char hydrogasification,is researched in fix bed reactor with rapid feed method.IR gas analyzer,Laser Raman,XRD and TEM,are used to analyze the gas component and change of char structure,to research the relationship between char microstructure and hydrogasification reactivity.Also,the effects of temperature,residence time and feed mode on the reactivity are researched.The main contents and results are summarized as follows:1.The pyrolysis process in rapid feed mode is divided into three stages by the gas components in different condition.The release of CO2 is inhibited by H2 in pyrolysis,and the inhibition raises with the increasing temperature;H2 provides more free radicals for the reaction turning the macromolecule into small molecule.Single crystal graphite is found in char,and the yields raises with increasing temperature.2.Raman is used to analyze the relationship of char structure and reactivity of hydrogasification.It was found that,with the rising temperature,the ratios of Raman band area Ad1/AG?AD2/AG?AD3/AG?AD4/AG are in gradually weakening growth,and the ratio AG/AAll decreases within 400-800? and increases within 800-900 ?.It is indicates that graphitization process of char is obviously emerged due to the increase of the relative amount of disordered carbon in pyrolysis.By fitting the Raman area ratio formula with hydrogasification reactivity,the obtained factor represents the hydrogasification reactivity of carbon microcrystal.The factor is bigger,and the reactivity the carbon microcrystal is better.3.The effects of temperature,residence time and feed mode on the reactivity are researched.The results show that the temperature has a significant effect on the distribution of productions;in the early stage of the reaction,the components of gases change a lot,in the later stage,the slow reaction happens for the amorphous carbon hydrogenation;the higher concentration of CH4 appears in flash hydrogasification.