The thermal performance of water cooled panels in electric arc steelmaking furnaces.

294 Pages·2017·9.04 MB·English

by  Caroline Fixter

The thermal performance of water cooled panels in electric arc steelmaking furnaces.
SIMON, M. J.
Available from the Sheffield Hallam University Research Archive (SHURA) at:
http://shura.shu.ac.uk/20363/
A Sheffield Hallam University thesis
This thesis is protected by copyright which belongs to the author.
The content must not be changed in any way or sold commercially in any format or medium
without the formal permission of the author.
When referring to this work, full bibliographic details including the author, title, awarding
institution and date of the thesis must be given.
Please visit http://shura.shu.ac.uk/20363/ and http://shura.shu.ac.uk/information.html for
further details about copyright and re-use permissions.
TELEPEN
100255230 3
Sheffield City Polytechnic Library
REFERENCE ONLY
ProQuest Number: 10701009
All rights reserved
INFORMATION TO ALL USERS
The quality of this reproduction is dependent upon the quality of the copy submitted.
In the unlikely event that the author did not send a complete manuscript
and there are missing pages, these will be noted. Also, if material had to be removed,
a note will indicate the deletion.
uest
ProQuest 10701009
Published by ProQuest LLC(2017). Copyright of the Dissertation is held by the Author.
All rights reserved.
This work is protected against unauthorized copying under Title 17, United States Code
Microform Edition © ProQuest LLC.
ProQuest LLC.
789 East Eisenhower Parkway
P.O. Box 1346
Ann Arbor, Ml 48106- 1346
THE THERMAL PERFORMANCE OF WATER
COOLED PANELS IN ELECTRIC ARC
STEELMAKING FURNACES
BY
M.J.SIMON
A THESIS SUBMITTED TO THE COUNCIL FOR NATIONAL
ACADEMIC AWARDS IN PARTIAL FULFILLMENT FOR THE
DEGREE OF DOCTOR OF PHILOSOPHY
SEPTEMBER 1989
COLLABORATING ESTABLISHMENT SPONSORING ESTABLISHMENT
British Steel Corporation, Department Of Metallurgy,
Stocksbridge Works. (Now Metals And Materials Engineering)
(Now United Engineering Steels) Sheffield City Polytechnic
DEDICATION.
This thesis is dedicated to all those who have helped
during the course of the work, especially the following:
V. Gibson
G. Briggs
D. Simraonds
D. Latimer and the T2 Team
"B" Furnace He Iters
ii
.
preface
All the work reported in this thesis was carried out
during the period for which the candidate was registered
for a higher degree.
In accordance with the regulations for PhD, a full
course in Metallurgical Process Management was
successfully completed. The details of the course are
given below : -
Module 1
Process Metallurgy
Mechanical Metallurgy
Advanced Thermodynamics
Module 2
Accountancy
Micro-Economics And Financial Control
Computational Methods And Operational Research
Module 3
Automatic And Computer Control
Metals And Competitive Materials
Refractor ies
Arc Furnace Steelmaking
Quality Control
Solidification Of Metals
Module 4
Industrial Case Studies
One of the case studies, which is related to this work,
is attached with the thesis, as Appendix VIII.
ABSTRACT.
The Thermal Performance Of Water Cooled Panels In
Electric Arc Steelsaking Furnaces.
H.J.Simon
The initial stage of the work was a study of an 80 tonne
industrial furnace, taking observations, panel water
temperature data and samples of slag layers from the
sidewalls. This resulted in a simple model of layer
formation which explained the observed structures, and
also the effect of slag layer thickness on heat losses
was examined.
However, the complexity and variety of structures found
were such that a full series of direct thermal
conductivity measurements was deemed impractical, and so
a theoretical model to calculate the thermal
conductivity of complex structures from the thermal
conductivities of it s components was developed. Other
aspects of heat transfer both within the furnace and
from the furnace interior to the water cooling were also
explored.
In order to obtain a reliable value of thermal
conductivity for the slag component of layer structures,
a technique was developed to measure the thermal
conductivity of the slag. This consisted of firstly
determining a viable route for the production of
homogenous samples, followed by the design, construction
and refinement of an experimental measuring rig. After a
large number of preliminary measurements, a series of
thermal conductivity values at temperatures between 300
and 800 C were measured using operating conditions
calibrated against a heat storage brick sample of known
thermal conductivity. These results were used to provide
the data for the theoretical thermal conductivity model,
which was then applied to real structures for which
thermal data was available. Comparison of the results
showed good correlation.
Finally, in the appended case study, the heat loss
calculation was applied for various furnace situations
to identify the potential heat loss savings that could
be achieved by controlling the slag layer thickness and
structure, and the financial implications.
IV
LIST OF CONTENTS.
page no.
Title Page i
Dedication ii
Preface iii
Abstract iv
List Of Contents v
List Of Symbols x
1. Literature Review
1.1. Arc Furnace Technology
1.1.1. A Brief History 1
1.1.2. The Modern Electric Arc Furnace 3
1.1.3. Water Cooled Panels 6
1.2. Arc Furnace Studies
1.2.1. Heat Transfer Within The EAF 12
1.2.2. Material Transfer Within The EAF 18
1.3. Slag Structures And Properties
1.3.1. The Physical Configuration Of
WCP Slag Layers 20
1.3.2. General Slag Microstructures
And Chemistry 21
1.3.3. Thermal Properties Of Slags 22
1.4. Thermal Conductivity
1.4.1. Theoretical Models Of Thermal
Conductivity 24
1.4.2. Thermal Conductivity Measurement 28
v
Industry Based Studies
2.1. Data And Sample Collection
2.2. Data And Sample Analysis
Theoretical Heat Transfer Studies
3.1. The Development Of A Model For Heat
Losses To Water Cooled Sidewalls
3.2. Heat Transfer Within The Furnace
3.2.1. Heat transfer Characteristics
Of Arcs
3.2.2. Radiation Networks
3.3. The Thermal Conductivity Of WCP
Slag Coatings
3.3.1. Assumptions And Objectives
3.3.2. The Computer Program
3.3.3. Derivation Of Data
Experimental Work
4. 1. Introduction
4.2. Sample Development
4.2.1. Fused Samples
4.2.2. Sintered Samples
4.3. Development Of The Apparatus
4.3.1. The Initial Design
4.3.2. The Refined Design
4.4. Experimental Technique
4.4.1. General Operating Procedure
4.4.2. Sequence Of Experiments
5. Results
5.1. Results Of Industry Based Studies
5.1.1. Results Of Furnace Observations 68
5.1.2. Results Of Sample Examination 69
5.1.3. Results Of Water Temperature
Measurements 72
5.2. Results Of Theoretical Heat
Transfer Studies 73
5.3 Experimental Results
5.3.1. Peripheral Work 74
5.3.2. The Initial Thermal Conductivity
Apparatus 74
5.3.3. The Refined Apparatus 76
6. Discussion
6. 1. Experimental Work
6.1.1. An Appraisal Of Experimental
Techn ique
6. 1.1.1. Thermal Conductivity
Measurement 80
6. 1.1.2. Other Techniques 82
6.1.2. Discussion Of Results
6.1.2. 1. Thermal Conductivity
Measurement 83
6.1.2.2. Other Results 84
6.1.3. Errors And Accuracy
6. 1.3.1. Thermal Conductivity
Measurements 84
vii