HYDRODYNAMICS OF SOLID-LIQUID

FLUIDIZED BED

PRESENTED BY KALYANI NAHAK

PRATIKSHYA RATHSAMBIT PRAKASH OJHA

GANESH SWAINANTARJAMEE SAHU

OUTLINES/CONTENTS INTRODUCTIONTYPES OF FLUIDIZATIONVARIBLES AFFECTING FLUIDIZATIONEXPERIMENTAL PROCEDURERESULTSDISCUSSIONSCONCLUSIONREFERENCE

INTRODUCTION

Solid-fluid contacting technique.It starts when force due to fluid equals with weight of bed.Greater ability to mix and segregate.Extremely acclaimed in the process industry.

TYPES OF FLUIDIZATIONMainly 2 types of fluidization are there.

Particulate fluidizationAggregative fluidization

PARTICULATE

FLUIDIZATION

Occurs at low velocity.Bed maintains its uniform character.Froude number less than unity.

AGGREGATIVE

FLUIDIZATION

Occurs at high velocity.Two phase i.e. emulsion phase and lean phase form.Froude number greater than unity.Also known as bubbling fluidization.

VARIABLES AFFECTING FLUIDIZATION

Quantity of solid feed.Liquid viscosity.Fluid distribution.Bed height.Particle size.Fluid and solid densities.Column diameter.Bed internals.

EXPERIMENTAL PROCEDURE

A weight amount of beads were taken.Water flow rate increase by control of

rotameterPressure drop ,bed height, void fraction

were measured.1kg salt added to the water.Fluidization started for new solution.Then,4 more new solutions prepared.For each solution pressure drop, bed

height , void fraction ,bed expansion ratio were measured.

RESULTSFollowing graphs were plotted:1. Flow rate vs. pressure drop across the bed2. Flow rate vs. pressure drop across the

distributor plate3. Flow rate vs. void fraction4. Flow rate vs. bed height5. Flow rate vs. bed expansion ratio

1.FLOW RATE VS PRESSURE DROP ACROSS THE BED

SI NO.

FLOW RATE

Pressure drop across the bed(N/M2

Pressure drop across the bed(N/M2)

Pressure drop across the bed(N/M2)

Pressure drop across the bed(N/M2)

Pressure drop across the bed(N/M2)

Pressure drop across the bed(N/M2)

LPH WATER

1037.3kg/m^3 sol.

1041.4kg/m^3 sol.

1041.7kg/m^3 sol.

1047.4kg/m^3 sol.

1058.2kg/m^3 sol.

1 0 0 0 0 0 0 02 25 494.42 492.96 492.8 369.59 369.42 246.073 50 1854.1 1848.6 1848.0 1724.8 1477.7 1476.44 75 2595.7 2834.5 2587.2 2710.3 2832.2 2460.75 100 3831.8 3820.4 3942.4 3447.5 3694.2 3568.06 125 5438.7 5422.6 5297.6 4558.3 4433.1 4429.37 150 7169.1 7024.7 7884.8 6036.6 5541.3 5413.58 175 8528.8 8380.3 9116.8 6775.8 6649.6 6890.09 200 9146.8 9119.8 9116.8 8254.2 7634.7 8366.410 225 9146.8 9119.8 9116.8 9116.6 9112.4 9104.611 275 9146.8 9119.8 9116.6 9112.4 9104.612 300 9119.8 9116.6 9112.4 9104.613 325 9119.814 350 9119.8

1.FLOW RATE VS PRESSURE DROP ACROSS THE BED

2.FLOW RATE VS PRESSURE DROP ACROSS THE

DISTRIBUTOR PLATE

2.FLOW RATE VS VOID FRACTIONSI. NO

FLOW RATE

VOID FRACTION

VOID FRACTION

VOID FRACTION

VOID FRACTION

VOID FRACTION

VOID FRACTION

LPH WATER

1037.3kg/m^3 sol

1041.4kg/m^3

1041.7kg/m^3 sol.

1047.4 kg/m^3 sol.

1058.2kg/m^3 sol.

1 0 0.391 0.391 0.391 0.391 0.391 0.3912 25 0.391 0.391 0.391 0.391 0.391 0.3913 50 0.391 0.391 0.391 0.391 0.391 0.3914 75 0.391 0.391 0.391 0.391 0.391 0.3915 100 0.391 0.391 0.391 0.391 0.391 0.3916 125 0.391 0.391 0.634 0.391 0.391 0.3917 150 0.391 0.391 0.652 0.391 0.391 0.3918 175 0.391 0.437 0.652 0.391 0.415 0.4789 200 0.391 0.582 0.652 0.391 0.543 0.51310 225 0.543 0.605 0.707 0.528 0.582 0.58211 275 0.570 0.722 0.582 0.643 0.61512 300 0.734 0.615 0.734 0.64313 325 0.805 0.6614 350 0.819

2.FLOW RATE VS VOID FRACTION

2.FLOW RATE VS AVERAGE BED HEIGHTSI. NO

FLOW RATE

BED HEIGHT(cm)

BED HEIGHT(cm)

BED HEIGHT(cm)

BED HEIGHT(cm)

BED HEIGHT(cm)

BED HEIGHT(cm)

LPH WATER

1037.3kg/m^3 sol

1041.4kg/m^3 sol.

1041.7kg/m^3 sol

1047.4kg/m^3 sol

1058.2kg/m^3 sol

1 0 2.4 2.4 2.4 2.4 2.4 2.42 25 2.4 2.4 2.4 2.4 2.4 2.43 50 2.4 2.4 2.4 2.4 2.4 2.44 75 2.4 2.4 2.4 2.4 2.4 2.45 100 2.4 2.4 2.4 2.4 2.4 2.46 125 2.4 2.4 3.2 2.4 2.4 2.47 150 2.4 2.4 4.4 2.4 2.4 2.48 175 2.4 2.6 4.8 2.4 2.5 2.89 200 3.2 3.5 5.2 2.4 3.2 3.010 225 3.4 3.7 5.9 3.1 3.5 3.511 275 5.25 3,5 4.1 3.812 300 5.5 3.8 5.5 4.113 325 7.5 4.314 350 8.1

2.FLOW RATE VS AVERAGE BED HEIGHT

2.FLOW RATE VS AVERAGE BED

EXPANSION RATIO

DISCUSSIONPressure drop decreases with density, ΔΡ/L=g(1-ɛ)(ρp-ρ).Void fraction increases with density , ɛ= 1-(δρ/Lg(ρp-ρ).Bed height and bed expansion ratio also

increase with density.

CONCLUSION It scopes ample opportunity for future study.Beads of different shape, density can be

implemented.

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