Based on heat and mass transfer characteristics of spontaneous combustion of coal,Arrhenius equation and the Ranz-Marshall correlation,a novel approach was proposed in this paper to estimate oxygen consumption rate of...Based on heat and mass transfer characteristics of spontaneous combustion of coal,Arrhenius equation and the Ranz-Marshall correlation,a novel approach was proposed in this paper to estimate oxygen consumption rate of self-ignition of coal at high temperature.Compared with the conventional methods,this approach involves not only kinetic properties of self-ignition of coal and temperature,but also the ambient air flow characteristics and diameter of coal particle.To testify the proposed approach,oxygen consumption rates at high temperature were measured by the programmable isothermal oven experiments.Comparisons between experimental and theoretical results indicate that the rates of oxygen depletion calculated by the proposed approach agree well with those measured from laboratory-scale experiments,which further validates the proposed approach.展开更多
文摘根据煤的硫分、灰分以及煤自燃过程中的耗氧速率、CO和CO2产生率等随温度变化的序列值与煤自然发火期之间存在的密切对应关系,建立了前向多层人工神经网络模型,用已有的煤自然发火实验数据对网络进行训练,得到了神经元间的联结强度,从而准确地表征这种对应关系.设计了一套油浴程序升温实验装置,确定了实验试管的尺寸和实验条件,从而能够准确测定煤自燃在不同温度下的耗氧速率及气体产生率.将煤样油浴程序升温实验数据及煤质分析数据代入人工神经网络,可算出煤的自然发火期.与煤自然发火实验相比,该方法测定煤样的自然发火期用煤量减少了99%以上,实验耗时缩短了90%以上,二者测试结果的偏差小于3 d.
基金Project(51534008) supported by the National Natural Science Foundation of China
文摘Based on heat and mass transfer characteristics of spontaneous combustion of coal,Arrhenius equation and the Ranz-Marshall correlation,a novel approach was proposed in this paper to estimate oxygen consumption rate of self-ignition of coal at high temperature.Compared with the conventional methods,this approach involves not only kinetic properties of self-ignition of coal and temperature,but also the ambient air flow characteristics and diameter of coal particle.To testify the proposed approach,oxygen consumption rates at high temperature were measured by the programmable isothermal oven experiments.Comparisons between experimental and theoretical results indicate that the rates of oxygen depletion calculated by the proposed approach agree well with those measured from laboratory-scale experiments,which further validates the proposed approach.
