Division of spontaneous combustion dangerous region and determination of nitrogen injection position in goaf of low level top coal caving mining face
Cao Jingqing
Wu Jianming
Zhou Chunshan
Tang Yibo
Abstract：In order to improve the inerting effect of the mine nitrogen injection technology,based on No.8202 fully-mechanized top coal caving mining face in Tashan Mine as a background,the layout of the bean tube and temperature monitoring and measuring system was applied to continuously monitor and measure the CO、O2 concentration and temperature of each measuring point in the goaf.The O2 concentration distribution contour map was drawn,the temperature rising rate was fitted and the spontaneous combustion danger area was determined and divided.The results showed that the area with a distance of 30～ 170 m between the air intake side of the goaf and the coal mining face and the area with a distance of 30～ 220 m between the air retuning side and the coal mining face were the spontaneous combustion danger areas.With the comparisons,when the nitrogen injection flow was 2 500 m3/h,the location of the nitrogen injection hole (50 m,100 m,150 m and 200 m behind the coal mining face was affected to the inerting effect.In the low level top coal caving goaf,when the location of the nitrogen injection hole was 150 m behind the coal mining face,the spontaneous combustion danger area was reduced about 60 m.In the deep section of the goaf,the CO volume fraction was obviously reduced and was stabilized about 19× 10-6.The inerting effect of the diluent oxygen was the best.
Keywords：coal spontaneous combustionfire prevention and control with nitrogen injectiontemperature monitoringspontaneous combustion danger zone
Publication Date：2017-01-01
Pages：6( 89-94 )