热风分布板对喷雾干燥塔气流分布的影响

Influence of hot air distribution plate on airflow distribution in spray drying tower

针对催化裂化催化剂喷雾干燥过程,建立100 kg·h^(-1)单喷枪压力式喷雾干燥塔模型,对不同塔体结构下干燥塔内热风分布规律进行模拟研究,并考察热风出口位置对干燥塔内温度分布、速率分布以及气流运动轨迹的影响。结果表明,干燥塔内未设置热风分布板,热空气呈旋流下降状态,喷枪下游存在明显低温区,流场分布均匀性相对较差;设置两层开孔均匀的热风分布板,热空气呈竖直向下运动状态,温度呈梯度分布,流场分布均匀性较好;设置两层中央开孔的热风分布板,热气流呈集中分布状态,喷枪附近气流速率和温度分布呈现中间高、四周低的趋势;调整出风烟道上的出风口位置对干燥塔内流场分布存在显著影响。

Aiming at the spray drying process of catalytic cracking catalyst,a 100 kg·h^(-1) single spray gun pressure spray drying tower model was established to simulate the distribution of hot air in the drying tower under different tower structures,and the influence of hot air outlet position on temperature distribution,velocity distribution and air flow trajectory in the drying tower was investigated.The results show that when there is no hot air distribution plate in the drying tower,the hot air is in a swirling downward state,there is an obvious low temperature zone downstream of the spray gun,and the uniformity of flow field distribution is relatively poor;When two layers of hot air distribution plates with uniform holes are set,the hot air moves vertically downward,the temperature is gradient distribution,and the flow field distribution is uniform;When two layers of hot air distribution plates with central holes are set,the hot air flow is in a centralized distribution state,and the distribution of air velocity and temperature near the spray gun tends to be high in the middle and low around.Changing the position of the hot air outlet in the outlet flue has a significant effect on the flow field distribution in the drying tower.