کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
155651 456907 2012 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Effect of impellers configuration on the gas dispersion in high-viscosity fluid using narrow annular gap unit. Part 1: Experimental approach
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی مهندسی شیمی (عمومی)
پیش نمایش صفحه اول مقاله
Effect of impellers configuration on the gas dispersion in high-viscosity fluid using narrow annular gap unit. Part 1: Experimental approach
چکیده انگلیسی

The effect of impellers configuration on the gas dispersion in a given raw material is investigated using a stainless steel and transparent agitated column with narrow annular gap (NAGU) equipped with right-angle cross paddle impellers or cylinder. Using right-angle cross paddle impeller in NAGU, several configurations are considered by changing: the angle (θ=0°–30°–45°) and the gap (δ=0 or 5 mm) between two successive elements. It is shown that the compact shifted geometry (δ=0 mm; θ=30°) is much more efficient to achieve total gas incorporation than the others. Conversely, the impeller configuration does not seem to influence bubble mean diameter. The mean diameter decreases slightly from 19 μm to 15 μm when the rotation speed increases from 200 rpm to 1600 rpm, whatever the configuration. Qualitative and quantitative aspects of the bubble breakup are investigated using a transparent NAGU. Tip breakup appears to be the predominant dispersion phenomenon in the system.


► Impact of impeller configuration on gas dispersion efficiency in food raw material.
► Power consumption is not correlated to the gas dispersion efficiency.
► Shifted paddles enhance dispersion efficiency.
► Bubble size distribution is independent of the impeller configuration.
► Tip streaming is the dominant mechanism of bubble breakup in such raw material.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Chemical Engineering Science - Volume 74, 28 May 2012, Pages 287–295
نویسندگان
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