Study On The Oxidation And Spontaneous Combustion Characteristics Of Jurassic Coal In Northern Shaanxi

In northern China, Jurassic coal seams are thicker, the quality of that are excellent andwhose metamorphic grade are lower，but easier spontaneous combustion. Adopting themethod of combining of theory analysis with experiment research in this paper, themicroscopic and macro characteristics in the oxidation procession of Jurassic coal seams innorthern Shaanxi are studied. The results lay foundations for the revealing of Jurassic coalspontaneous combustion mechanism and the research of forecasting and controlling of coalspontaneous combustionUsing industrial analyzer, elemental analyzer, X-ray diffraction (XRD) and Fourierinfrared spectrometer, the coal composition, aromatic microcrystalline structure andcharacteristics of functional groups are analyzed. And the physical and chemical structurecharacteristics of Jurassic coal in northern Shaanxi are researched.According to the synchronous thermal analysis experiments,5characteristictemperatures which indicate the characteristics of coal spontaneous combustion are analyzed.The apparent activation energy and pre-exponential factors that are kinetic parameters arestudied in the oxidation process which includes the water evaporation and desorption stageand oxygen weight-gaining stage. And the most probable mechanism function which is basison method of Bagchi of oxidation process is identified.Adopting the Fourier infrared spectrometer, the variations of the functional groups in themolecular structure of Jurassic coal in northern Shaanxi are analyzed, which are at thecharacteristic temperatures. The results of the greater influence on the reactive functionalgroups which include hydroxyl and methyl ether in the molecular structure on the oxidationreaction are researched.According to the analysis of macro parameters of oxygen consumption rate, gasproduction rate and heating intensity in the process of coal spontaneous combustiontemperature-programed experiment, and contrasting with the other coal samples, combiningwith the analysis of kinetic parameters and variations of the functional groups in the molecular structure, the oxidation procession of Jurassic coal in northern Shaanxi areexplained.