Criterion of initial coal spontaneous combustion with prediction model of concentration ratio of CO2 and CO

In order to improve the relability of early prediction for the coal spontaneous combustion,the concentration ratio φ of CO2 and CO were applied as the eval uation index,the spontaneous combustion oxidized experiment data of the bituminous coal and lignite from several mines were selected,Origin software was applied to the processing of the corresponding relationship between φ and temperature and the study was conducted on the early evolution of coal spontaneous combustion. The study re sults showed that the ftting method of bituminous coal test data with the priority in sequence was index function ftting method,five times of polynomial ftting method,four ti mes of polynomial ftting method and three times of polynomial ftting method. The test data of five times polynomial ftting method was recommended to be applied. A spon taneous combustion early evaluation model of bituminous coal from Gengcun Mine was established,t inspection method was applied to verify the reliability of the model an d to reveal the wave type reduction variation law of φ at establish early period of coal spontaneous combustion with coal temperature increased. There was a transition peri od existed in each oxidized reaction period and the temperature variation value of the transition period was within 5。C and could provide certain guide significances to esta blish early prediction model of the coal spontaneous combustion.