Experiment on secondary oxidation spontaneous combustion characteristics of low metamorphic degree coal

In order to control spontaneous combustion of the second coal mining face and to contain the secondar oxidation disaster occurred and developed,a temperature rising fest with the coal spontaneous combustion prgram wasappied to the experiment study of the secondary oxidatin spontaneous combustion featreson the four low melanorphic degree coal sampes inclucing the selected lgniefrom Yuishu Nline, Yuhua long fame coal Anshan non caking coal and Huanglig No.1 wealkly caking coal The resulis showed that, before the coal spontaneous combustion and oxc atonreacion,the C0 concentration occured fom the secondary oxidized :oal samples oxygen consumption rate, heat releasing intensity and other spontaneous combution feature indexes would b al igher thn the youmes occured from te first oxidized cal samples Afer the cal spontaneous combustion and oxidation reaction,the spontaneous combustion feature indeves of the secondary oxidized coasamples would be lower than the frst oxidized coal samples. n the late perod of the reacton.the pyrolysis woud produceC2H4 and th gas concenraion cured frm the secondary oxdized coal samles woul be lo wer than the frst oxidized cal samples. The feature temperature poit of the secondary oxdized cal samples woud be ll moved forward and would b less than the frt oxdized coal sampes ywhich llsrated that the oxidation of the second oxidzed cal samples was enhanced and the danger of the spontaneous combustion was increased.