Industrial Air Quality and Ventilation: Controlling Dust Emissions

410 Pages·2014·49.47 MB·English

by  Ivan Nikolayevich Logachev

ENGINEERING-ENVIRONMENTAL L
o
g
a
c
h IInndduussttrriiaall
e
Industrial Air Quality and Ventilation v
•
L
o
g
a
Controlling Dust Emissions c
h
e
v
AAiirr QQuuaalliittyy
In the field of industrial ventilation and air quality, a lack of adequate analysis
for aerodynamic processes, as well as a shortage of properly equipped computer
facilities, has forced specialists to rely on an empirical approach to find answers I
n
in the past. Commonly based on crude models, practical data, or countertypes,
d
the answers often offered have been imprecise.
u aanndd

Summarizing the results of the authors’ research conducted over the past s
t
40 years, Industrial Air Quality and Ventilation: Controlling Dust Emissions
r
examines air injection in granular material streams and defines the closed i
a
hood capacity widely used in the mechanical reprocessing of minerals. This
l
book introduces a methodological approach (dynamic theory) that broadens VVeennttiillaattiioonn
A
the range of granular materials, including inter-heated material. It considers
i
the mechanisms of ejecting air in different variations from uniform air motion r

processes in closed chutes to the forming of accelerated air streams in a free Q
particles flow. It also provides the scientific basics of calculation for local exhaust
u
ventilation dust production (aspiration) and enables readers to accurately apply
a
these results to the mechanical processing of various materials. CCoonnttrroolllliinngg
l
i
t
• Describes the engineering methods for calculating the amounts of y
aspirated air for various industries and technological units
a DDuusstt EEmmiissssiioonnss
• Assists in developing new environmentally clean and competitive advanced n
technologies and equipment for the processing of granular materials d
• Proposes new technical solutions that are more sanitary and require
V
less energy and water consumption
e
• Looks at specific industry examples of localization of release n
t
i
Industrial Air Quality and Ventilation: Controlling Dust Emissions proposes l
a
low power consumption-based technical solutions and outlines more accurate
t
methods of calculating recommended performance. Richly illustrated with
i
practical suggestions and techniques, the text includes real-world applications o
in the field of aerodynamic processes within gravitational fluxes of granular n
material and encourages the development of new environmentally clean
and competitive advanced technologies and equipment for the processing of
granular materials.
Ivan Nikolayevich Logachev
K22272
Konstantin Ivanovich Logachev
6000 Broken Sound Parkway, NW
Suite 300, Boca Raton, FL 33487
711 Third Avenue
New York, NY 10017
an business
2 Park Square, Milton Park
www.crcpress.com Abingdon, Oxon OX14 4RN, UK www.crcpress.com
Industrial
Air Quality
and
Ventilation
Controlling
Dust Emissions

Industrial
Air Quality
and
Ventilation
Controlling
Dust Emissions
Ivan Nikolayevich Logachev
Konstantin Ivanovich Logachev
Boca Raton London New York
CRC Press is an imprint of the
Taylor & Francis Group, an informa business
CRC Press
Taylor & Francis Group
6000 Broken Sound Parkway NW, Suite 300
Boca Raton, FL 33487-2742
© 2014 by Taylor & Francis Group, LLC
CRC Press is an imprint of Taylor & Francis Group, an Informa business
No claim to original U.S. Government works
Version Date: 20130923
International Standard Book Number-13: 978-1-4822-2217-3 (eBook - PDF)
This book contains information obtained from authentic and highly regarded sources. Reasonable efforts
have been made to publish reliable data and information, but the author and publisher cannot assume
responsibility for the validity of all materials or the consequences of their use. The authors and publishers
have attempted to trace the copyright holders of all material reproduced in this publication and apologize to
copyright holders if permission to publish in this form has not been obtained. If any copyright material has
not been acknowledged please write and let us know so we may rectify in any future reprint.
Except as permitted under U.S. Copyright Law, no part of this book may be reprinted, reproduced, transmit-
ted, or utilized in any form by any electronic, mechanical, or other means, now known or hereafter invented,
including photocopying, microfilming, and recording, or in any information storage or retrieval system,
without written permission from the publishers.
For permission to photocopy or use material electronically from this work, please access www.copyright.
com (http://www.copyright.com/) or contact the Copyright Clearance Center, Inc. (CCC), 222 Rosewood
Drive, Danvers, MA 01923, 978-750-8400. CCC is a not-for-profit organization that provides licenses and
registration for a variety of users. For organizations that have been granted a photocopy license by the CCC,
a separate system of payment has been arranged.
Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used
only for identification and explanation without intent to infringe.
Visit the Taylor & Francis Web site at
http://www.taylorandfrancis.com
and the CRC Press Web site at
http://www.crcpress.com
Contents
Preface.......................................................................................................................xi
List of Symbols ......................................................................................................xiii
Chapter 1 Dust and Air Mechanics of Bulk Material Transfer ............................1
1.1 Transfer Groups as Air Pollution Sources .................................1
1.1.1 Intensity of Dust Emissions ..........................................1
1.1.2 Primary Means of Dust Emission Control ..................8
1.2 Theoretical Models of Air Suction with a Gravitational
Solid Stream ............................................................................12
1.2.1 Butakov–Hemeon Model and Its Development ..........14
1.2.2 Semiempirical Models ...............................................22
1.2.3 Dynamic Theory and Research Methodology for
Injection Properties of a Particle Stream ..................24
1.2.3.1 Mathematical Modeling ..............................25
1.2.3.2 Experimental Studies ..................................26
1.2.3.3 Industrial Evaluation ...................................28
1.3 Classification of Bulk Material Streams .................................29
Chapter 2 Aerodynamic Properties of Particles in the Gravitational
Flow of a Chuted Bulk Material .........................................................33
2.1 Peculiarities of Bulk Material Motion in Chutes ....................33
2.1.1 Modes of Motion ........................................................35
2.1.2 Particle Distribution ...................................................38
2.1.3 Motion Speed .............................................................41
2.2 Aerodynamic Characteristic of a Single Particle ....................45
2.2.1 Geometric Shape ........................................................48
2.2.2 Dynamic Shape of Particles .......................................50
2.2.3 Resistance Coefficient ................................................53
2.3 Sedimentation of Particles .......................................................55
2.3.1 Particle Motion in the Air Stream ..............................55
2.3.2 Aerodynamic Drag of a Particle Moving at an
Increasing Rate ...........................................................57
2.4 Method for Evaluating the Aerodynamic Characteristic
of Particle Gravitational Flow ................................................65
2.4.1 Channel Pressure Variation ........................................66
2.4.2 Experimental Evaluation of the Method for
Determining the Particle Drag Factor ........................72
v
© 2010 Taylor & Francis Group, LLC
vi Contents
Chapter 3 Air Injection in Chutes .......................................................................75
3.1 Isothermal Flow .......................................................................75
3.1.1 Averaged Aerodynamic Characteristic of Particles ......78
3.1.1.1 Monofractional Stream ..............................78
3.1.1.2 Polyfractional Stream ................................81
3.1.2 Air Injection with a Stream of Particles in a
Prismatic Chute ..........................................................84
3.1.2.1 Pressure Distribution .................................86
3.1.2.2 Induced Air Velocity .................................95
3.1.3 Peculiarities of the Dynamic Interaction of
Air and a Bulk Material Stream in Laminar
Flow in a Chute ........................................................101
3.1.4 Air Injection in a Bin Chute with a Uniform
Distribution of Particles ...........................................104
3.1.5 Air Mechanics of a Stream of Particles with
High Bulk Concentrations ........................................107
3.2 Effect of Heat and Mass Exchange ........................................110
3.2.1 Inter-Component Heat Exchange in an
Inclined Chute ..........................................................111
3.2.2 Thermal Head ...........................................................113
3.2.3 Air Velocity in the Chute .........................................116
3.2.4 Influence of Mass Exchange on the Volumes
of Induced Air ..........................................................118
3.3 Aerodynamics of an Unsteady Particle Flow in the Chute .....120
3.3.1 Sudden Change in the Material Flow .......................120
3.3.2 Smooth Change in the Material Flow ......................129
Chapter 4 The Aerodynamics of Solid-Particle Jets .........................................133
4.1 Air Injection in a Jet of Freely Falling Particles ...................134
4.1.1 Initial Equations .......................................................134
4.1.1.1 Changes in Volumetric Particle
Concentration in a Jet of Material ............134
4.1.1.2 Volumetric Forces of Interaction
between Components ................................137
4.1.1.3 Fluid Dynamics Equations .......................139
4.1.2 Structure of Air Streams in a Flat Jet of
Loose Matter ............................................................144
4.1.2.1 Self-Similar Motion Equations ................144
4.1.2.2 Approximate Solution of Self-Similar
Motion Equation .......................................152
4.1.2.3 Uniformly Distributed Particles ...............154
4.1.2.4 One-Dimensional Problem ......................157
4.1.2.5 Exponentially Distributed Particles .........169
4.1.2.6 Effect of Pressure Gradient ......................175
© 2010 Taylor & Francis Group, LLC
Contents vii
4.1.3 Injection of Air in an Axially Symmetric Jet of
Freely Falling Particles ............................................184
4.1.3.1 Self-Similar Motion Equations .................185
4.1.3.2 Solving the Self-Similar Equation ...........190
4.2 The Aerodynamics of a Jet of Particles in a Channel ...........196
4.2.1 Plane-Parallel Flow ..................................................197
4.2.2 One-Dimensional Flow ............................................200
Chapter 5 Engineering Solutions for Dust Release Containment and Air
Dedusting .........................................................................................213
5.1 Basic Premises for Calculating Local Suction Capacity .......214
5.1.1 Initial Equations .......................................................214
5.1.2 Determining the Minimum Negative Pressure ........215
5.1.2.1 Interaction between an Injected Air Jet and
Suction Spectrum of a Local Suction Unit ......215
5.1.2.2 Compressive Effect ...................................219
5.1.2.3 Thermal Pressure in the Cowl ..................221
5.1.2.4 Optimizing the Choice of Negative
Pressure .....................................................221
5.1.3 Choosing an Aspiration Layout and Calculating
the Performance of Local Suction Units at
Handling Facilities ...................................................222
5.1.3.1 Conveyor-to-Conveyor Transfers ..............224
5.1.3.2 Conveyor (Feeder)–Crusher–Conveyor ....229
5.1.3.3 Conveyor–Screen–Conveyor ....................232
5.1.3.4 Dry Magnetic Separation Assembly .........234
5.1.3.5 Cascade Installations ................................236
5.1.3.6 Specific Issues of Injection-Driven
Air Discharge Calculations for
Complex Configurations of Chutes ...........237
5.1.4 Calculations of Air Replacement in High-Speed
Machinery ................................................................242
5.1.4.1 Hammer Breakers as Fans ........................242
5.1.4.2 Aspiration Volumes ..................................246
5.2 Dust Release Intensity and Mitigation of Initial Dust
Concentration in Aspirated Air .............................................251
5.2.1 Overview and Primary Features of Dust Release
Sources .....................................................................251
5.2.1.1 Dust Carryover from Aspiration Cowls .....251
5.2.1.2 Concentration and Particle Size
Composition of Dust in Aspirated Air ......253
5.2.2 Decrease in Dust Release Intensity ..........................257
5.2.2.1 Changes in Total Dust Releases
Depending on Structural and Process
Parameters of Load-Handling Facilities ....260
© 2010 Taylor & Francis Group, LLC
viii Contents
5.2.3 Techniques for Intensifying Inertial Dust
Precipitation in Aspirating Cowls ............................271
5.2.3.1 Inertial Trap Using a Plate Grid
inside Cowl ...............................................271
5.2.4 Reduction of Dust Concentration in Aspiration
Funnels .....................................................................279
5.2.4.1 Initial Dust Concentration as a
Function of Air Velocity in Aspiration
Funnels ......................................................279
5.2.4.2 Dust Precipitation in Dust Receivers/
Separators .................................................281
5.2.4.3 Dust Precipitation in a Local Cyclone-
Type Suction Unit/Dust Trap ....................291
5.2.4.4 Dust Precipitation in a Local Dust-
Separating Suction Unit with a Filter
Element ....................................................295
5.3 Sources of Fugitive Atmospheric Dust Releases in
Outdoor Storage of Iron Ore Pellets ......................................298
5.3.1 Outdoor Storage Locations as Atmospheric
Emission Sources at Ore Beneficiation Plant
Industrial Sites ..........................................................298
5.3.1.1 Storage Process Layout .............................299
5.3.1.2 Primary Dust Emission Sources ...............301
5.3.2 Examining Dust Release Intensity at Iron
Ore Pellet Storage Sites ............................................303
5.3.2.1 Distribution of Dust Released by a
Ground-Based Source ...............................303
5.3.2.2 Field Surveys of Dust Plume Structure.....309
5.3.2.3 Intensity of Primary Dust Emission
Sources ......................................................315
5.3.2.4 Procedure for Determining Losses of
Powdered Material during Stockpiling
of Fired Pellets ..........................................318
5.3.3 Dust Release Containment in Fired Pellet Storage ..321
5.3.3.1 Fencing Off the Flowing Material
When Pellets Are Dumped into the
Stockpile ...................................................321
5.3.3.2 Local Suction Units and Aspiration
Systems of Storage Facilities ....................329
5.4 Fugitive Emissions and Containment of Dust during
Loading of Iron-Ore Pellets in Railway Cars ........................339
5.4.1 Dust Emission Containment Designs for Loading
Bins ...........................................................................339
© 2010 Taylor & Francis Group, LLC
Contents ix
5.4.2 Performance Calculations for Local Suction Units
of Pellet Loading Bins ..............................................344
5.4.3 Improving Aspiration Efficiency for Pellet
Handling in Transfer Bin Housings ..........................351
Conclusion ............................................................................................................359
Appendix Initial Aerodynamic Equations for a Bulk Material Stream ......363
A.1 Phenomenological Method of Dynamic Equation
Development for Two-Component Stream ............................363
A.1.1 Inter-Component Interaction ....................................364
A.1.2 Accounting Equations ..............................................367
A.2 Space–Time Method of Averaging Accounting Equations ...373
A.2.1 Mass Transfer Equation ............................................374
A.2.2 Pulse Transfer Equation ...........................................376
A.2.3 Energy Transfer Equation ........................................378
References ........................................................................................379
References .............................................................................................................383
© 2010 Taylor & Francis Group, LLC