Research On Co Source Of Zaoquan Coal Mine2#Coalbed Workface

The coal seam belongs to easily spontaneous combustion coal seam in Zaoquan coalmine, in the mining process, CO gas comes out from the upper corners of fully mechanizedand caved working faces, concentrations of CO could rise than normal level in workfaceand return airflow. Theoretical analysed the regular pattern of CO volume fraction of workface110205and130201, and review extensive literature, considered as possible sources ofCO can be coal seam distribution, coal crushing, oxidation of coal wall, and transport fromgob. This article focuses on the first three which predecessors rarely involved.Conducted drilling experiment in a new exposed workface, experimental resultsshowed that the CO concentration decreases with increasing drilling depth. COconcentration decreases with the increase of time in the deeper drilling; the results show thatCO not occurrence in Zaoquan coal mine,2#coal seam. Sampling in Zaoquan coal mine,designed and conducted coal crushing experiments, experimental results show that both inthe air atmosphere and anaerobic conditions, coal crushing will have a certain concentrationof CO gas, and CO rised higher under nitrogen than air environment. The results proved thatit will produce a certain amount of CO in the production process when the coal mine coalcutting machine is running and it will increased the level of CO volume fraction in workfaceand return airflow. Studied the workface temperature distribution of110205with the use ofinfrared photography instrument, the maximum temperature was found in the cutter of coalcutting machine when it was friction with coal face. Based on coal face temperaturedistribution, temperature-programmed experiments were conducted, reached a fittingformula of CO production rate uuder different temperature, standard oxygen concentration;preliminary estimates of the coal face and top coal CO produces rate, proved that undernormal ventilation conditions, the reason is not sufficient to affect the distribution of CO concentration in the workface. Finally, workface CO sources and migration patterns hasbeen studied with the use of ANSYS Fluent, proved that when the cutting mehaine isrunning, CO concentration has increased near the cutting mechaine,work face and backairflow, but has little effect on the upper corner of the workface.Comparison with field observations, that the study results are accurate and credible,this paper provides the basis for study of coal spontaneous combustion index gas.