The spontaneous combustion liability of coal can be determined by using different experimental techniques.These techniques are well-known in their application,but no certain test method has become a standard to prove ...The spontaneous combustion liability of coal can be determined by using different experimental techniques.These techniques are well-known in their application,but no certain test method has become a standard to prove the reliability of all of them.A general characterisation which included proximate and ultimate analyses,petrographic properties and spontaneous combustion tests(thermogravimetric analysis(TGA)and the Wits-Ehac tests)were conducted on fourteen coal and four coal-shale samples.The spontaneous combustion liability of these samples collected between coal seams(above and below)were predicted using the TGA and the Wits-Ehac tests.Six different heating rates(3,6,9,15,20 and 25C/min)were selected based on the deviation coefficient to obtain different derivative slopes and a liability index termed the TGspc index.This study found that coal and coal-shale undergo spontaneous combustion between coal seams when exposed to oxygen in the air.Their intrinsic properties and proneness towards spontaneous combustion differ considerably from one seam to the other.The Wits-Ehac test results agreed with the TGspc results to a certain extent and revealed the incidents of spontaneous combustion in the coal mines.展开更多
文摘The spontaneous combustion liability of coal can be determined by using different experimental techniques.These techniques are well-known in their application,but no certain test method has become a standard to prove the reliability of all of them.A general characterisation which included proximate and ultimate analyses,petrographic properties and spontaneous combustion tests(thermogravimetric analysis(TGA)and the Wits-Ehac tests)were conducted on fourteen coal and four coal-shale samples.The spontaneous combustion liability of these samples collected between coal seams(above and below)were predicted using the TGA and the Wits-Ehac tests.Six different heating rates(3,6,9,15,20 and 25C/min)were selected based on the deviation coefficient to obtain different derivative slopes and a liability index termed the TGspc index.This study found that coal and coal-shale undergo spontaneous combustion between coal seams when exposed to oxygen in the air.Their intrinsic properties and proneness towards spontaneous combustion differ considerably from one seam to the other.The Wits-Ehac test results agreed with the TGspc results to a certain extent and revealed the incidents of spontaneous combustion in the coal mines.
