TRANSPORT CHARACTERISTICS OF SUSPENSIONS: II. MINIMUM TRANSPORT VELOCITY FOR FLOCCULATED SUSPENSIONS IN HORIZONTAL PIPES

Journal Article · Fri Sep 01 04:00:00 EDT 1961 · A.I.Ch.E. Journal

DOI:https://doi.org/10.1002/aic.690070316· OSTI ID:4842772

Thomas, D G

The minimum transport velocity was determined for flocculated thorium oxide and kaolin suspensions flowing in glass pipes. The pipes ranged from 1 to 4 in. in diameter, and the concentration was varied from 0.01 to 0.17 volume fraction solids. Two flow regimes were observed depending on the concentration of the suspension. In the first the suspension was sufficiently concentrated to be in the compaction zone and hence had an extremely low settling rate. The second regime was observed with more dilute suspensions which were in the hindered-settling zone and settled ten to one-hundred times faster than slurries which were in compaction. The concentration for transition from one regime to the other was dependent on both the tube diameter and the degree of flocculation. The suspension particles were smaller than the thickness of the laminar sublayer, and they settled according to Stokes' law for the particular conditions of this study. Under these circumstances the relation developed for dilute suspensions is consistent with particle transfer in the radial direction owing to Bernoulli forces on the particle and the action of turbulent fluctuations which penetrate the laminar sublayer. For concentrated suspension in compaction the minimum transport velocity was given by a characteristic critical Reynolds number. (auth)

• Research Organization: Oak Ridge National Lab., Tenn.
• NSA Number: NSA-15-029367
• OSTI ID: 4842772
• Journal Information: A.I.Ch.E. Journal, Journal Name: A.I.Ch.E. Journal Vol. Vol: 7
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ALUMINUM SILICATES
CLAYS
CONFIGURATION
ENGINEERING AND EQUIPMENT
FILMS
FLUID FLOW
FLUIDS
GLASS
KAOLIN
MECHANICS
PARTICLES
PRECIPITATION
QUANTITATIVE ANALYSIS
QUANTITY RATIO
REYNOLDS NUMBER
SLURRIES
SMOKES
SUSPENSIONS
THORIUM OXIDES
TUBES
TURBULENCE
VELOCITY
VOLUME