撞击气流床气化炉内浓度场和温度场的数值模拟

Numerical simulation of concentration and temperature in impinging entrained-flow gasifier

运用PDF燃烧模型模拟以柴油为模拟气化介质的撞击气流床气化炉气化时的过程,结果与实验较吻合。还考察氧燃料比与合成气组成的关系,分析了气化炉中的温度和浓度分布情况。模拟结果表明:氧燃料比与合成气组成关系很大,随着氧燃料比例降低合成气中有效气(CO+H2)浓度升高;通过温度变化预测撞击火焰上升的高度,得出模拟条件下撞击火焰上升的高度与气化炉内径之比在1.0左右;随着反应进行,气化炉轴向上O2浓度迅速下降,H2浓度逐渐升高,H2O浓度逐渐降低。

PDF model was employed to simulate the gasification process of diesel oil in impinging entrained flow gasifier. The result agrees well with the experimental value. The effect of oxygen-fuel ratio on syngas composition and the distribution of temperature and concentration in the entrained flow gasifier were studied. It＇s showed that： the effect of oxygen-fuel ratio on syngas is great. When oxygen-fuel ratio is low, the ratio of CO and H2 in syngas is high. The flame height could be forecasted through the change of temperature. It＇s showed that the ratio of flame height and gasifier inner diameter is 1.0. With the reaction process, the concentration of O2 is rapidly decreased along the axis, and the concentration of HE is gradually increased, and the concentration of H2O is gradually decreased.