Experiment study on high temperature point migration law in coal bunker during coal spontaneous combustion process

In onder to get the migration law of the high temperature point during the coal spontaneous combustion in the coal bunker and to prevent the coal spontaneous combustion accident occurred in the coal bunker, the large coal low temperature spontaneous combustion test rig with similar air leakage field and structure was applied to test the location migration law of the high temperature point during the temperature rising process of the bulk coal.A comprehensive prevention and control measures with "a periodic cleaning, temperature reduction and oxy-gen reduction, monitoring and control"were provided. The results showed that the high temperature point was at 3/5 of coal bunker height, then high temperature point would steadily move to the air income side at the coal bunker bottom along the central shaft of bunker. Mean-while, the high temperature point would change to the south east direction along the vertical central shaft, finally, it would be stayed at bottom of coal bunker near the air income side and would then develop to the location with higher edge space rate in the coal bunker. At the low tem-perature(within 100℃) stage, when the air volume was less than 0.6 m2/h, the high temperature point would be highly reduced along the central shaft. At the high temperature stage, the high temperature point would not migrate with the air volume increased.