2 kg试验焦炉炼焦过程传输行为的数值模拟

为了研究炼焦过程中煤传热传质现象的规律,建立2 kg试验炼焦过程流动、传热及传质过程的数学模型。模型中将装炉煤/焦饼假设为多孔介质,结合水分蒸发冷凝与挥发分析出子模型,模拟了配合煤焦化过程中的传热、水分传递、挥发分析出及荒煤气流动等现象,并分析水分含量对煤层中心温度的影响。结果表明,数学模型可反映试验焦炉炼焦过程中的传输现象。炼焦过程中,焦饼温度会受到烟道回流空气的影响,顶部装炉煤成焦所需时间较长。在水蒸气冷凝的作用下,装炉煤中心水分含量会在焦化过程中逐渐升高,并使装炉煤中心温度达到100 ℃时形成恒温平台。

Numerical simulation of transfer behavior during coking process in 2 kg experimental coke oven

To investigate the mechanism of heat and mass transfer phenomenon of coal during the coking period, a mathematical model of flow, heat transfer and mass transfer process of 2 kg experimental coke oven was established. Coal and coke were assumed to be porous media. Combined with moisture evaporation and condensation as well as volatile components evolution sub-model, the phenonmen of heat transfer, moisture transfer, volatile evolution and coke oven gas flow in coking process of experimental coke oven were analyzed, and the influence of moisture content on the coal center temperature was investigated. The results show that the model can reflect the transfer phenomena in experimental coke oven coking process. Coke charge temperature will be influenced by the backflow air from flue, and the coking time will be longer at the top of coke charge. Under the influence of condensation phenomenon, moisture content in the center of coke charge will gradually increase during the coking process, and form a constant temperature platform when the center temperature of coal arriving at 100 ℃.