Critical Value of CO of Forecasting Coal Spontaneous Combustion

<正> CO has been used widely in the production process of colliery as an index gas to predict spontaneouscombustion of coal.But in some collieries there are CO gas in the upper corner of the face all the times, sometimeCO gas even exceeds the regulated critical index. This phenomenon is much more obvious in the fully-mechanizedlongwall face and fully-mechanized longwall and top-coal caving face.Although many measures of fire-proof andfire-extinguishing have been adopted, the flowing amount of CO gas can be only decreasd, but can not beeliminated completely. Using the different kinds of coal, the experiment of coal oxidation was made at the lowtemperature. The experiment indicates that some kinds of coal can produce CO under the condition of normaltemperature oxidation, sometime the CO consistency is very high, and the intension of CO can be decreased withoxidation time prolonging.Selecting rational critical value of CO is the kev to predicting spontaneous combustion ofcoal correctly and reliably. The proble