scholarly journals Hydrodynamics of Turbulent Bed Contactor with Non Newtonian Liquids

2021 ◽  
Author(s):  
Hadil Abukhalifeh
Keyword(s):  
Pressure Drop ◽  
Aqueous Solutions ◽  
Methyl Cellulose ◽  
Gas Holdup ◽  
Newtonian Liquid ◽  
Hydrodynamic Characteristics ◽  
Liquid Holdup ◽  
Viscous Liquids ◽  
Newtonian Liquids ◽  
Bed Expansion

Little information is available in literature in terms of the hydrodynamic characteristics in a turbulent bed contractor [sic] (TBC) with viscous liquids. In this study, the hydrodynamic characteristics in three-phase turbulent bed contactor with counter current flow of air and non-Newtonian liquid was studied and compared with that of Newtonian liquid under consistent conditions. Aqueous solutions of carboxy methyl cellulose (CMC) with apparent viscosities ranged between 5 to 25 cP were used as non-Newtonian liquid. The hydrodynamic parameters iinvestigatedwere: bed pressure drop, minimum fluidization velocity, liquid holdup, bed expansion, and gas holdup. The effect of rheological properties of the CMC aqueous solutions and operating parameters on hydrodynamic characteristics of the TBC were examined. Results showed that increasing CMC concentration increased the net pressure drop across the bed and the liquid holdup, while the gas holdup and bed expansion decreased. At that quoted apparent viscosity range, aqueous solutions of CMC behaved as Newtonian viscous liquids in the TBC.

scholarly journals Hydrodynamics of Turbulent Bed Contactor with Non Newtonian Liquids

2021 ◽  
Author(s):  
Hadil Abukhalifeh
Keyword(s):  
Pressure Drop ◽  
Aqueous Solutions ◽  
Methyl Cellulose ◽  
Gas Holdup ◽  
Newtonian Liquid ◽  
Hydrodynamic Characteristics ◽  
Liquid Holdup ◽  
Viscous Liquids ◽  
Newtonian Liquids ◽  
Bed Expansion

Little information is available in literature in terms of the hydrodynamic characteristics in a turbulent bed contractor [sic] (TBC) with viscous liquids. In this study, the hydrodynamic characteristics in three-phase turbulent bed contactor with counter current flow of air and non-Newtonian liquid was studied and compared with that of Newtonian liquid under consistent conditions. Aqueous solutions of carboxy methyl cellulose (CMC) with apparent viscosities ranged between 5 to 25 cP were used as non-Newtonian liquid. The hydrodynamic parameters iinvestigatedwere: bed pressure drop, minimum fluidization velocity, liquid holdup, bed expansion, and gas holdup. The effect of rheological properties of the CMC aqueous solutions and operating parameters on hydrodynamic characteristics of the TBC were examined. Results showed that increasing CMC concentration increased the net pressure drop across the bed and the liquid holdup, while the gas holdup and bed expansion decreased. At that quoted apparent viscosity range, aqueous solutions of CMC behaved as Newtonian viscous liquids in the TBC.

Modeling of Gas Holdup and Pressure Drop Using ANN for Gas-Non-Newtonian Liquid Flow in Vertical Pipe

2014 ◽  
Vol 917 ◽  
pp. 244-256 ◽  
Author(s):  
Nirjhar Bar ◽  
Sudip Kumar Das
Keyword(s):  
Pressure Drop ◽  
Liquid Flow ◽  
Multilayer Perceptron ◽  
Transfer Functions ◽  
Gas Holdup ◽  
Newtonian Liquid ◽  
Training Algorithms ◽  
Vertical Pipe ◽  
Frictional Pressure Drop ◽  
Hidden Layer

This paper is an attempt to compare the the performance of the three different Multilayer Perceptron training algorithms namely Backpropagation, Scaled Conjugate Gradient and Levenberg-Marquardt for the prediction of the gas hold up and frictional pressure drop across the vertical pipe for gas non-Newtonian liquid flow from our earlier experimental data. The Multilayer Perceptron consists of a single hidden layer. Four different transfer functions were used in the hidden layer. All three algorithms were useful to predict the gas holdup and frictional pressure drop across the vertical pipe. Statistical analysis using Chi-square test (χ2) confirms that the Backpropagation training algorithm gives the best predictability for both cases.

Gas Holdup Characteristics in a Tapered Bubble Column

2003 ◽  
Vol 1 (1) ◽  
Author(s):  
Kai Zhang ◽  
Yulong Zhao ◽  
Bijiang Zhang
Keyword(s):  
Pressure Drop ◽  
Bubble Column ◽  
Particle Diameter ◽  
Liquid System ◽  
Gas Holdup ◽  
Internal Diameter ◽  
Slurry Concentration ◽  
The Difference ◽  
Bed Expansion ◽  
Solid System

Gas holdup characteristics were explored experimentally in a tapered bubble column of 3.00m height. The internal diameter increased from 0.10 m at the bottom to 0.20 m at the top. Two gas holdup characteristic parameters investigated were local gas holdup and overall gas holdup. Local gas holdup was measured by pressure drop method whilst overall gas holdup was measured by both pressure drop and bed expansion techniques. Axial gas holdup profile decreased from the bottom to the top in the range of the experiments. Overall gas holdup reached a maximum in transitional regime for either the gas-liquid system or the gas-liquid-solid system with low slurry concentration, but increased monotonically for gas-liquid-solid system with high slurry concentration. Overall gas holdup decreased with increasing static slurry height or solid concentration. The effect of particle diameter on gas holdup was too insignificant to be considered. Experiments were carried out in a cylindrical column to compare the difference between cylindrical and tapered bubble columns. Moreover, an empirical correlation was presented to estimate overall gas holdup in the tapered slurry bubble column (TSBC).

Pressure drop, bed expansion and liquid holdup in a three phase spouted bed contactor

1974 ◽  
Vol 52 (2) ◽  
pp. 180-184 ◽  
Author(s):  
D. V. Vukov ÍC ◽  
F. K. Zdanski ◽  
G. V. Vunjak ◽  
Ž. B. Grbavčić ◽  
H. Littman
Keyword(s):  
Pressure Drop ◽  
Spouted Bed ◽  
Liquid Holdup ◽  
Three Phase ◽  
Bed Expansion

ESTIMATION OF PRESSURE DROP FOR NON-NEWTONIAN LIQUID FLOW THROUGH BENDS USING ADAPTIVE NON-PARAMETRIC MODEL

2020 ◽  
Vol 47 (1) ◽  
pp. 59-69
Author(s):  
Suman Debnath ◽  
Anirban Banik ◽  
Tarun Kanti Bandyopadhyay ◽  
Mrinmoy Majumder ◽  
Apu Kumar Saha
Keyword(s):  
Pressure Drop ◽  
Liquid Flow ◽  
Parametric Model ◽  
Newtonian Liquid ◽  
Flow Through ◽  
Non Parametric

Gas holdup in bubbled beds of aqueous solutions of electrolytes

1977 ◽  
Vol 42 (9) ◽  
pp. 2642-2650
Author(s):  
F. Kaštánek ◽  
J. Kratochvíl ◽  
J. Pata ◽  
M. Rylek
Keyword(s):  
Aqueous Solutions ◽  
Gas Holdup ◽  
Solutions Of Electrolytes

Process characteristics of screw impellers with a draught tube for Newtonian liquids. Pumping capacity of the impeller

1981 ◽  
Vol 46 (9) ◽  
pp. 2021-2031 ◽  
Author(s):  
Pavel Seichter
Keyword(s):  
Viscous Liquid ◽  
Energy Criterion ◽  
Velocity Profiles ◽  
Newtonian Liquid ◽  
Creeping Flow ◽  
Geometrical Arrangement ◽  
Draught Tube ◽  
Process Characteristics ◽  
Newtonian Liquids

Velocity profiles and pumping capacity have been determined using a thermistor anemometer in a vessel equipped with a screw impeller. In region of the creeping flow of a Newtonian liquid, i.e. for Re <15, the dimensionless pumping capacity is dependent on the geometrical arrangement of the mixing system. The efficiency was assessed of individual configuration from the value energy criterion expressing the dimensionless power requirements for recirculation of a highly viscous liquid in a vessel equipped with a screw impeller.

The effect of two-phase flow regime on hydrodynamics and mass transfer in a horizontal-tube gas-liquid reactor

1985 ◽  
Vol 50 (3) ◽  
pp. 745-757 ◽  
Author(s):  
Andreas Zahn ◽  
Lothar Ebner ◽  
Kurt Winkler ◽  
Jan Kratochvíl ◽  
Jindřich Zahradník
Keyword(s):  
Mass Transfer ◽  
Pressure Drop ◽  
Flow Regime ◽  
Liquid Flow ◽  
Horizontal Tube ◽  
Liquid Holdup ◽  
Two Phase ◽  
Flow Rates ◽  
Type Relation ◽  
Good Agreement

The effect of two-phase flow regime on decisive hydrodynamic and mass transfer characteristics of horizontal-tube gas-liquid reactors (pressure drop, liquid holdup, kLaL) was determined in a cocurrent-flow experimental unit of the length 4.15 m and diameter 0.05 m with air-water system. An adjustable-height weir was installed in the separation chamber at the reactor outlet to simulate the effect of internal baffles on reactor hydrodynamics. Flow regime maps were developed in the whole range of experimental gas and liquid flow rates both for the weirless arrangement and for the weir height 0.05 m, the former being in good agreement with flow-pattern boundaries presented by Mandhane. In the whole range of experi-mental conditions pressure drop data could be well correlated as a function of gas and liquid flow rates by an empirical exponential-type relation with specific sets of coefficients obtained for individual flow regimes from experimental data. Good agreement was observed between values of pressure drop obtained for weirless arrangement and data calculated from the Lockhart-Martinelli correlation while the contribution of weir to the overall pressure drop was well described by a relation proposed for the pressure loss in closed-end tubes. In the region of negligible weir influence values of liquid holdup were again succesfully correlated by the Lockhart-Martinelli relation while the dependence of liquid holdup data on gas and liquid flow rates obtained under conditions of significant weir effect (i.e. at low flow rates of both phases) could be well described by an empirical exponential-type relation. Results of preliminary kLaL measurements confirmed the decisive effect of the rate of energy dissipation on the intensity of interfacial mass transfer in gas-liquid dispersions.

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