Experimental Study Of Coal Spontaneous Combustion Releasing Heat And Produce Gases

The spontaneous combustion character of ten types coal samples which are different metamorphic grade was studied,include industry analysis,spontaneous combustion characteristic temperature,activation energies,a pure exponential factor,releasing heat,air quantity,metamorphic grade which effect on index gas of generation.Firstly,the moisture content,ash content,volatile content and fixed carbon content of ten coal sample which have different metamorphic grade were obtained by industrial analyzer;then the TG-DSC curve was obtained by simultaneous thermal analyzer,a three-stage-division method for the TG curve of spontaneous coal combustion,namely,water-lost stage,heavy-increased staged and combustion reaction stage,the characteristic temperature of coal spontaneous combustion were obtained,the activation energies and are exponential factor of coal samples spontaneous combustion in each stage were calculated base on TG data,the activation energies of coal spontaneous combustion in each stage is gradually increase with the increase of coal sample metamorphic grade,the releasing heat of coal samples spontaneous combustion in each stage were calculated base on DSC data,the releasing heat of coal spontaneous combustion in each stage is more large with the increase of coal sample metamorphic grade;At the end,the temperature programmed system of coal sample was established by tube furnace and gas chromatography and so on,the lignite was studied through temperature programmed experiment in different air quantity,the stronger the air quantity,the index gas concentration is lower and the O2 concentration is higher during the process of coal spontaneous combustion,subsequently,ten coal sample which have different metamorphic grade were studied through temperature programmed experiment in the constant air quantity,the law of concentration,formation rate and oxygen consumption rate of O2?CO?CO2?CH4?C2H6?C2H4?C2H2?C3H8 variation with temperature were obtained,the theoretical foundation was provided for preventing coal spontaneous combustion and making measures of fire extinguishing in mine fire zone.