Mixing Time for Different Diameters of Impeller at a High Solid Concentration in an Agitated Vessel

JOURNAL OF CHEMICAL ENGINEERING OF JAPAN

Katsuhide Takenaka³  Waldemar Bujalski¹  Arthur W. Etchells²  Alvin William Nienow¹  Koji Takahashi³  Saverio Paolini¹  Alessandro Paglianti¹ 

[1] School of Chemical Engineering, The University of Birmingham;The DuPont Company, DuPont Engineering Technology;Department of Chemistry and Chemical Engineering, Yamagata University

关键词: Mixing Time;    High Solid Concentration;    Chemineer HE-3;    Impeller Diameter;   

DOI  :  10.1252/jcej.38.309

来源: Maruzen Company Ltd

【 摘 要 】

References(18)Cited-By(2)In the previous studies, it has been found that there is a significant influence of the solids on the liquid phase mixing time at high solid concentrations. This is due to appearing a clear liquid layer above the cloud solid layer at a certain specific power input. The state of solids suspension and the mixing time affect the purity, productivity and selectivity of the reaction and the size distribution and morphology of the precipitation and crystallisation. Consequently, more information in these conditions is necessary in order to operate properly the reactor handling particle suspensions.In this study, the effect of D/T ratio (the ratio of impeller to tank diameter) on solid suspension and mixing time has been investigated in a stirred tank equipped with Chemineer HE-3 impeller, which is typically used for solid–liquid mixing at high solid concentrations. The maximum mixing time for the largest D/T employed in this study is the longest despite almost the same specific power input and height of interface. However, to use the large D/T has led a high degree of homogeneous suspension and fast mixing time with a small increase in power input. On the contrary, large power input is necessary to disappear the cloud layer when the small D/T is used.

【 授权许可】

Unknown