Effects of vessel baffling on the drawdown of floating solids
-
Joanna Karcz
and
Beata Mackiewicz
Abstract
The effects of baffling of an agitated vessel on the production of floating particles suspension are presented in this paper. Critical agitator speed, needed for particles dispersion in a liquid agitated in a vessel of the inner diameter of 0.295 m, was determined. The just drawdown agitator speeds were defined analogously to the Zwietering criterion. Specific agitation energy was calculated from the power consumption experimental data obtained by means of the strain gauge method. The experiments were carried out for twelve configurations of the baffles differing in number, length and their arrangement in the vessels. The following high-speed impellers were used: up- and downpumping six blade pitched blade turbines, Rushton turbine, and propeller. The impeller was located in the vessel in the height equal to two-thirds or one-third of the vessel diameter from the bottom of the vessel. The results were described in the form of a dimensionless equation.
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© 2008 Institute of Chemistry, Slovak Academy of Sciences
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Articles in the same Issue
- Biosynthesis of methanol from methane by Methylosinus trichosporium OB3b
- Influence of reaction medium composition on enzymatic synthesis of galactooligosaccharides and lactulose from lactose concentrates prepared from whey permeate
- Immobilization of modified penicillin G acylase on Sepabeads carriers
- Granulation of activated sludge in a laboratory upflow sludge blanket reactor
- Investigation of the effect of fluid elasticity on a cake filtration process
- Lab-scale testing of a low-loaded activated sludge process with membrane filtration
- Calcium sulphate scaling in membrane distillation process
- Characterization and filtration performance of coating-modified polymeric membranes used in membrane bioreactors
- Informational analysis of the grinding process of granular material using a multi-ribbon blender
- Effects of vessel baffling on the drawdown of floating solids
- N2O catalytic decomposition — effect of pelleting pressure on activity of Co-Mn-Al mixed oxide catalysts
- Intelligent control of a pH process
- Influence of suspended solid particles on gas-liquid mass transfer coefficient in a system stirred by double impellers
- A three-phase nonequilibrium model for catalytic distillation
- Membrane processes used for separation of effluents from wire productions
- A simple and efficient synthesis of 3-substituted derivatives of pentane-2,4-dione
- Formation of hydrated titanium dioxide from seeded titanyl sulphate solution
- Pyrolytic and catalytic conversion of rape oil into aromatic and aliphatic fractions in a fixed bed reactor on Al2O3 and Al2O3/B2O3 catalysts
- Oxidation of thiophene over copper-manganese mixed oxides
- Study of partitioning and dynamics of metals in contaminated soil using modified four-step BCR sequential extraction procedure
- Preparation and properties of a new composite photocatalyst based on nanosized titanium dioxide
