流型和进料位置对连续搅拌釜混合过程的影响

Effects of flow pattern and feeding position on mixing process in continuous stirred tanks

对应用于聚丁烯聚合反应中连续搅拌釜内的流体流动进行了模拟计算,研究桨叶组合形式、不同进料位置及搅拌转速对流场、搅拌功率、混合时间和停留时间分布的影响规律。研究结果表明:搅拌器为MKW+3DMK时,流速分布更加均匀,而搅拌功率相比于单一桨叶的更大。当采用4UMK搅拌器时,进料位置在第1层和第2层桨叶之间投料混合效果好;当采用4DMK和MKW+3DMK搅拌器时,进料位置在第4层桨叶附近投料混合效果好。此外,桨叶组合和搅拌转速对物料平均停留时间影响较小,釜内流体流动状态接近全混流。这些研究结果可为聚丁烯连续聚合反应釜桨叶结构和进料位置的设计优化提供一些理论指导。

The fluid flow in a continuous stirred tank reactor used in polybutene polymerization reaction was simulated.The effects of impeller configuration,different feed positions,agitation speed on the flow field,stirring power,mixing time and residence time distribution were investigated.The results show that when the impeller is MKW+3DMK,the velocity distribution is more uniform,but the stirring power is higher compared to a single impeller.When a 4UMK impeller is used,the mixing effect is better while the feeding position between the first and second layers of impellers.For 4DMK and MKW+3DMK impellers,the feeding position near the fourth layer of impellers is more effective.In addition,the impeller configuration and agitation speed has little effect on the average residence time of the material,and the fluid flow in the reactor is close to complete mixing.These results can provide some theoretical guidance for the design and optimization of impeller structure and feed position in continuous polybutene polymerization reactor.