Study On The Effect Of Temperature Rise Of Deoxygenation On Coal Metamorphism

The intrusion of igneous rock affects coal quality,coal rock and coal structure.In the process of magma intrusion,temperature and oxygen are the main control conditions of magma intrusion.Taking long-flame coal as the research object.The evolution mechanism of coal metamorphism induced by temperature rise of oxygen exclusion was studied by pyrolysis kinetics theory.The main achievements of this paper are as follows:1)Four stages of long-flame coal under the influence of temperature were determined by tg experiment:drying dehydration(180℃),primary pyrolysis(266℃),secondary pyrolysis(427℃)and surface polycondensation(561℃).Coal sample reduce volatile content,fixed carbon content,vitrinite reflectance,which in a pyrolysis to secondary pyrolysis stage porosity,the fixed carbon and the change of vitrinite reflectance is the most significant.2)Combined with the characteristics of temperature point,through Fourier transform infrared spectroscopy,the results show that the temperature in the coal main functional groups,aliphatic,hydroxyl,aromatic C=C all showed a trend of decline,the aromatic C=C drop at least,carbonyl and carboxyl in oxygen containing functional groups such as basic completely disappear,only aromatic C-H content increased.3)Through pyrolysis kinetics analysis,the results show that the pyrolysis of coal is carried out in a second-order reaction mode.Many chemical bonds are broken from 180℃to 427℃,and the activation surge occurs from 561℃ to 800℃,resulting in the condensation of semi-coke.The functional groups is controlled by diffusion is low.The pyrolysis of C-O at 30～427℃ conforms to the first-order reaction mode,at 427～800℃conforms and the activation energy increases.The pyrolysis of hydroxyl at 427～800 ℃conforms to the second-order reaction mode.The pyrolysis mode of aromatic C=C at266～800℃ conforms to the second-order reaction occurs polycondensation reaction and has higher activation energy.Figure 31;Table 4;Reference 46...