在直径0.48 m的立式搅拌槽内研究了4种组合式螺带搅拌桨的粉体混合性能,考察了搅拌转速、粉体物料装填高度和搅拌桨型对粉体混合性能的影响,分析了径向与轴向上的粉体混合情况. 结果表明,搅拌转速是影响粉体混合的重要因素,增加搅拌转速能明显缩短混合时间,转速44.0 r/min时的混合因子π3比转速8.7及26.5 r/min时下降50%及30%以上;在搅拌桨内部附加较小的内桨使功率略有增加,但可显著缩短混合时间,转速44.0 r/min时能使π3下降50%,提高混合效率.
Four different helical ribbon impeller combinations were used to study the powder mixing in a stirred tank with diameter of 0.48 m. The effects of rotation speed, powder filling level, impeller combination on the mixing performance, and the powder mixing performance at the axial and radial cross were investigated. The results showed that the rotational speed was the important factor of effect the powder mixing. The mixing factor π3 at rotational speed of 44 r/min fell by 30% and 50% than the speed was 26.5 and 8.7 r/min. The extra small impeller installed inside the big impeller could increase the power consumption, but significantly reduce the mixing factor π3 50% at the rotation speed of 44 r/min, enhanced the mixing performance.
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