Modern Blast Furnace Ironmaking: An Introduction

276 Pages·2020·39.005 MB·English

by  M. Geerdes, R. Chaigneau, O. Lingiardi, R. Molenaar, R. van Opbergen, Y. Sha, J. Warren

Modern
Blast Furnace
Ironmaking
an introduction
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Maarten Geerdes
Rénard Chaigneau
Oscar Lingiardi
Ron Molenaar
Rob van Opbergen
Yongzhi Sha
Peter Warren
Modern

Blast Furnace
Ironmaking
an introduction
Fourth Edition, 2020
© 2020 The authors and IOS Press. All rights reserved.
ISBN 978–1–64368–122–1 (print)
ISBN 978–1–64368–123–8 (online)
DOI 10.3233/STAL9781643681238
Published by IOS Press under the imprint Delft University Press
Publisher
IOS Press BV
Nieuwe Hemweg 6b
1013 BG Amsterdam
The Netherlands
tel: [phone]
email: [email protected]
www.iospress.nl
LEGAL NOTICE
The publisher is not responsible for the use which might be made of the following information.
PRINTED IN SLOVENIA
v
Preface
This fourth edition of “Modern Blast Furnace Ironmaking” has been prepared
by an international staff of experts from three continents. We are indebted to
Cor van der Vliet and Hisko Toxopeus†, who prepared the first two editions
of the book and agreed to hand over future editions of the book to the next
generation. Prof. Ivan Kurunov† and John Ricketts made a great contribution
to the third edition. Co–authors of the fourth edition are Prof. Yongzhi Sha
from the China Iron and Steel Research Institute, Ron Molenaar, retired
superintendent of the IJmuiden Blast Furnaces and Peter Warren, presently
working at British Steel in the United Kingdom and Rob van Opbergen,
experienced in casthouse operation and operational improvement.
The objective of the book is to share our insights, that optimization of the
blast furnace is not only based on “best practice transfer”, but also requires
conceptual understanding of why a measure works. In other words, operational
improvement is based not only on know–how, but also on know–why.
Compared to the third edition, we have added operational examples of many
furnaces. The examples are for illustration only and cannot be traced to a
specific furnace. Since the earlier edition, new instrumentation like cameras at
tuyeres and the top are playing a much more prominent role. We have rewritten
the sections on balances and elaborated the section on operational challenges.
We are indebted to the many colleagues we have worked with. We are grateful
to Jennifer Wise–Alexander and Tim Vander, who will find part of their
contributions to the second edition in the book. Edo Engel did the editing, as
in the previous three editions. Danieli Corus supported publication of the book.
For the fourth edition we enjoyed support from many colleagues worldwide.
We are indebted to N. Bleijendaal, J. Borrego and L. Castro (AHMSA, Mexico),
P. Etchevarne (Ternium, Argentina), D. Fisher (British Steel, UK), G.J.
Gravemaker, Dr. B. Nightingale (Australia), T. Spiering (fellow traveler), Yuanyi
Liu (China), Dr. Fuming Zhang (China) and P. Zonneveld.
We learn by sharing our knowledge. We wish the same to our readers.
Maarten Geerdes, Rénard Chaigneau, Oscar Lingiardi, Ron Molenaar,
Rob van Opbergen, Yongzhi Sha, Peter Warren
September 2020
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vii
Contents
Preface v
List of Symbols and Abbreviations x
Chapter I Introduction to the Blast Furnace Process 1
1.1 Global steel production 1
1.2 Hot metal production 2
1.3 Blast furnace process 3
1.4 Equipment 5
1.5 Book overview 10
Chapter II Blast Furnace Process and Internal Structure 11
2.1 Gasifying coke and coal 11
2.2 Counter–current reactor 12
2.3 Internal layer structure 13
2.4 How gas flows through the furnace 16
2.5 Processing the ferrous burden 17
2.6 Furnace efficiency 18
2.7 Casting hot metal and slag 19
Chapter III The Ferrous Burden 23
3.1 Introduction 23
3.2 Iron ore 24
3.3 Quality demands for the blast furnace burden 26
3.4 Sinter 30
3.5 Pellets 35
3.6 Lump ore 40
3.7 Metallics charge and briquettes 41
3.8 Interaction of burden components 42
3.9 Chemical control of the burden 44
Chapter IV Coke 47
4.1 Function of coke in the blast furnace 47
4.2 Coal blends for coke making 49
4.3 Coke quality 50
4.4 Coke size distribution 54
4.5 Strength of coke 55
4.6 Coke deadman 58
4.7 Overview of international quality parameters 63
4.8 Coke, nut coke and high PCI 65
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Chapter V Injection of Coal, Natural Gas and Oil 67
5.1 Properties of coal, oil and gas 68
5.2 Coal injection 70
5.3 Natural gas injection 82
5.4 Coal–gas co–injection 85

Chapter VI Blast Furnace Gas and Processing the Ferrous Burden 87
6.1 Introduction 87
6.2 Hot metal and slag composition 87
6.3 Top gas composition from a one–stage mass balance 89
6.4 The temperature profile and chemical reactions 91
6.5 Carbon balance: estimation of direct reduction 92
6.6 Gas and burden composition during processing 96
6.7 Permeability 102
6.8 Blast furnace efficiency 109
6.9 Productivity 111
6.10 Process symmetry 112
Chapter VII Burden Distribution 117
7.1 The movement of gas and burden 117
7.2 Burden descent: system of vertical forces 121
7.3 Burden distribution and gas flow control 123
7.4 Coke and ore layer thickness 132
7.5 Finding an optimal burden distribution 135
7.6 Double bell furnaces 136
7.7 Permeability of cohesive zone 137
Chapter VIII Hot Metal and Slag 141
8.1 Processing the ferrous burden above the cohesive zone 141
8.2 Softening 143
8.3 Melting 145
8.4 Formation of hot metal and slag as cast 147
8.5 Slag properties 155
Chapter IX Casting Hot Metal and Slag 161
9.1 Introduction 161
9.2 Liquid level and the blast furnace process 162
9.3 Monitoring casting regimes 167
9.4 The taphole 172
9.5 Single taphole furnaces 177
9.6 Casting problems and remedial actions 178
9.7 Hot metal and slag separation 180