10.Study on the location of combustible layers incoal gangue hills of dongsheng mining area

Abstract:

To investigate the vertical position of the flammable layer in lowsulfur and highvolatile coal gangue dumps in the DongshengMining Area,and to provide the location of flammable risk zones for targeted grouting,field experiments,similar simulation experiments,and lossonignition experiments were conducted to explore the vertical laws of particle size distribution and coal content distribution in coal gangue dumps. A fire risk index model was established by coupling height,particle size,and coal content,and risk levels were classified for different heights of the coal gangue dump based on the fire risk index. The results show that the relative error ofD50 between the similar simulation experiment and the field measurement is less than 5% ,indicating the reliability of the method;theflammable layer of the coal gangue dump is located at a relative height ratio of 0. 63 ~ 0. 74,which is classified as highrisk and extremely highrisk fire levels through the fire risk index model;the flammable layer is between 9. 45 m and 11. 1 m in the vertical heightof the coal gangue dump,and the design depth of the grouting borehole on the top platform is 7 m,which can cover the flammable layer.

Keywords: coal gangue dump;particle size distribution;coal content distribution;flammable layer;fire risk index model