Yin R. Metallurgical Process Engineering
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288 Metallurgical Process Engineering
plant, it is not always the bigger, the better. In an ultra-large-scale steel plant
with irrational process structure, the production would fall into disarray and
the general layout would be unfavourable. As a result, the excessively higher
investment, the higher transportation cost, the higher energy consumption, the
lower production efficiency and the lower capital return would happen.
The cost
of
steel products is composed
of
investment cost, production cost,
transportation and sales costs. Too long sales radius (weighted mean) would lower
the profit margin
of
unit product. Therefore, considering different steel products
and different regional conditions, the production scale
of
an individual steel plant
should falI into a rational range. Modern steel plants are folIowing the developing
trend
of
specialized production, regionalized sales and deep processing products.
However, market demands for steels are diversified, and the technical progress
leads to specialized production in a steel plant. Solution to this contradiction
should not be building omnipotent ultra-large-scale steel plant, as it would cause
problem like difficulties in raising funds and low capital return. Developing trend
should be forming regional steel corporation or even trans-national steel corpora-
tion or specialized steel corporation.
It
may be a merger
of
steel enterprises with
integrated financing operations; also be market-allocated, investment-divided
strategic alIiance
of
steel enterprises with partial dependent capitals and manage-
ments for each other. As for a steel plant which would be a link
of
an eco-
industrial band (zone) in the future, it may form a consolidated corporation with
enterprises
of
other sectors, such as power plant, cement plant, etc.
8.6.5 Issues about investment
To gain market competitiveness, steel plants need to rely on strategic invest-
ment for sustainable development. However, the investment strategy has to be
carefully arranged, as the steel industry is now an industry with low investment
return. In investing for a steel plant, considerations should be given how to im-
plement innovations in structure and mode by best using existing knowledge
and achievements. In Fig. 8.9, strategic investment issues like investment direc-
tion, investment order, investment strength, investment opportunity, capital
make
-up,
capital raising and risk assessment are shown from the perspective
of
multi-target thinking.
It
should be noted that steel plant restructuring is a process
of
technological
progress; it is also a process involving more and more investment decision-
making knowledge. Much creativity is also involved in the course
of
investment
decision-making. For instance, it has been pointed out in chapter I that the main
reason
of
Chinese steel industry, which had risen high emerged in the 1990s, is
that the application and integration
of
6 key/common technologies had smoothed
out the manufacturing processes in Chinese steel plants, particularly the processes
Chapter 8 The Structure and Mode
of
Steel Plant Process
289
for long product manufacturing. At the same time, attentions had been given to
strengthen the dynamic orderly investment to make the input - output efficiency
higher, techno
-eco
nomic profits noticeable and the investment reduced accord-
ingly as the sinicization
of
technologies and equipment.
From the worldwide point
of
view, the investment experiences
of
interna-
tional iron and steel industry since the 1973 oil crisis show that, with the tech-
nologies progressing and steel plant restructuring, the investment
of
unit steel
product has been decreasing gradually. And the higher
-l
evel technologies, the
lower the unit investment. Specifically speaking, the investment per tonne
of
steel products produced by EAF
-thin
slab continuous casting and rolling proc-
ess would be reduced to around 300 USD, while by BF- BOF
-t
hin slab con-
tinuous casting and rolling process to
600
~
800
USD even lower (Wiesinger,
1997) (Fig. 8.26). What should be vigilant about in the course
of
the develop-
ment
of
a steel plant is that too high unit investment would weaken the competi-
tiveness in the market.
"---
...............................
EAF
min-
imill steel plant
2010
2000
.;.
:
.:
.:
::- .
Compa
ctintegrated
s
t
~:
;·
·
~
;~
~
i
·
..·..· .
1990
Cl
<Il
1000
::l
;:,
'8
'C
800
..!:!
"8
"0
..c:
...
600
<:>
'"
<:>
u
C
400
..,
S
~
.s
200
'c
::l
0
1980
Yea
r
Fig. 8.26 Comparison of unit investment cost for integrated steel plant, compact integrated
plant and EAF mini-mi ll
References
Chu M 0 (1995) Initial understanding
of
the position and role
of
transportation in a steel
plant general layout, Engineering
ofiron
and Steel Works(5) :34-36 (in Chinese)
Chu M 0 (1997) Again on transportation and layout, Metallurgical Transportation (4):3-5
(in Chinese)
Hubbard M A (1990) Process economics
of
desulfurization from blast furnace to steel ladle.
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Steelmaking Conference Proceedings, AIME 73:357-365
Liu Y C (1997) Production practice
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blast furnace profile evolution, Iron and Steel, 34
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of
SF volume on intensified smelting with smelt-
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of
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Umezawa K
(I992)
Scrap Melting Process-Current Status and Future Prospect, Tetsu-to
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of
new technology opportunities and pitfalls, Iron &
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Yin R Y (1993) The evolution
of
metallurgical process functions and the optimization
of
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Yin R Y
(I994)
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of
steelmaking tech-
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of
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of
steel industry, Engineering Sci-
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6)
: 24-32 (in Chinese)
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of
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of
evaluating
SF's
smelting intensification, Ironmaking
(2): 1-6 (in Chinese)
Chapter 9
Steel
Plants
and
the
Environment
Issues
Resources, environment,
and
eco-friendliness are issues that steel plants must face in con-
temporary times. Since the 1960s, international steel industries exerted great efforts in
terms
of
environmental protections, have gone through periods
of
public hazard and pollu-
tion controls, energy conservations and emission reductions, and are now undergoing a
period
of
cleanerproduction and green manufacturing. They are also step-by-step develop-
ing and expanding eco-industrial chains, and in the more advanced countries, promoting
the construction
of
regional circular economic systems.
As part
of
afuture sustainable development strategy, the functions
of
the steel manufac-
turing process will be extended to:
• Thefunction
of
steel product manufacturing;
• Thefunction
of
energy conversion;
• Thefunction
of
waste treatment and recycling.
Thefuture mode
of
steel plants development will gradually take, in the main, twoforms:
steel plants
of
suburb type, and steel plants at harbor eco-industrial parks.
In the course
of
one and a half century development, especially the quick devel-
opment at late part of the
z
o"
century, steel industry had already reached a gigan-
tic large scale and a high technological level. Reviewing the development
of
late
50
~
60
years, it can be seen that steel plant gained economy scale benefit mainly
by enlarging production scales b
ef
ore 1970s. After the oil crisis, steel plant gradu-
ally optimized structure by doing a profound manufacturing process r
ef
orm, and
then formed quasi- continuous/continuous manufacturing process, finally realized
optimization
of
technology and economy. As a steel plant consumes a great deal
of resource and energy, furthermore, brings lots of emissions, it will inevitably
conflict with the environment
of
the earth
if
without recycling and reusing.As the
published report by Rome Club
The Limit to Growth, people have gradually real-
ized that the earth is the only home base which human can live on. In order to
actualize the harmonious relationship between human and environment, we must
insist on the sustainable development, and form "3R" (reduce, reuse and recyce)
R. Yin, Metallurgical Process Engineering
© Metallurgical Industry Press, Beijing and Springer-Verlag Berlin Heidelberg 2011
292
Metallurgical Process Engineering
type circular economy society. The problem
of
ecosystem has already become the
fundamental problem in the end
of
20
th
century which affecting the development
the steel industry.
9.1 Issues on Sustainable Development
Topics
of
sustainable development,manufacture linkage and evolution
of
the val-
ues
of
goods, features and multi-levels
of
the influence
of
steel plants on envi-
ronment were discussed in this section.
9.1.1 Put forward
of
the topic
In the 20
th
century, the progress
of
the science and technology greatly im-
proved the social economy's development and quickened the process
of
indus-
trialization and urbanization all over the world. At the same time, lacking
of
comprehensive understanding
of
earth environment, the ecosystem has been
sharply worsened. The main reason is to carry on large scale production with-
out limiting the use
of
resource and energy. At the same time the problems
aroused by large consumption and the thrown wastes after consumption are
not considered well. These all bring a series pollution problems aroused by
destroying the ecological self-cleaning ability (they include public hazard
pollution problem, industrial pollution problem, daily life pollution problem
and earth environment problem etc., Fig.9.1). Thus the environmental prob-
lems became more and more visible. Environment protection attracts the at-
tention
of
the entire world . From then on, humans start to consider the funda-
mental problems such as earth environment, eco-balance, then raise the strat-
egy
of
sustainable development.
Earth
enviro
nmenta
l
problems
Long term
Fig.9.1 Connotation
of
environmental problems and relationships among different types
of
environmental problems
Chapter 9 Steel Plants and the Environment Issues
293
Through practice, people begin to understand that to solve the environ-
mental problems successful, only doing the end
-pipe
treatment is insufficient.
And too much end-pipe treatment will aggravate enterprise and society's eco-
nomic burden; even affect the developing power
of
enterprise and society.
Therefore,
if
we want to change the disadvantage factors
of
environment, we
must set about the root, which brings out the problem (so called source treat-
ment). That's mean it covers all steps including the raw material supply-
manufacture
of
products
-consumption
of
products
-waste
abandon/recycling.
Only adopt the strategy considering the full life cycle, can we solve the problem
thoroughly.
Therewith, people start to think about a series
of
topics, concept, connotation
and countermeasure
of
sustainable development from different levels. Such as:
innocuous treatment
of
pollutant and poisonous substance; energy saving, cleaner
production-green manufacturing, eco-industrial chain, circular economy society
and so on (Yin, 2002).
9.1.2 Manufacture linkage and evolution
of
the values
of
com-
modity
The existence and development
of
human's society can't survive without manu-
facturing industry.
Of
course, the concept and connotation
of
manufacturing in-
dustry are developing progressively with time. Now, manufacturing industry can
be defined as: by relevant manufacture process the useful resources and energy
are transformed into industrial goods and consuming goods .The connotation
of
modern manufacture process not only covers steps from raw materials and energy
to finished goods but also the concept expansion from processing to manufacture
chains. The manufacture chains include the full life cycle
of
the products from
product design, manufacture process design, manufacturing process to finished
product, emission controlling with its innocuous treatment, product use phase,
abandoning and recycling.
With the time passes, the manufacture chains have developed from
"river
model" to "lake model" (Stahel, 2007) little by little. The"river model" is
refered to the linear structure
of
the industrial economy, while the "lake
model"is refered to the closing-loop material circulation
of
the industrial
economy.
Steelmaking process belongs to the process manufacturing industry. The
life cycle
of
steel products will involve such a cause-effect linkage inclusive
of
exploitation
of
resources and energy, transportation, processing, assembling,
use phase, abandoning, classification and recycling (See manufacture chains
Fig. 9.2).
294 Metallurgical Process Engineering
Energy
Abandoning
1--
- ---'------1
Fig. 9.2 Connotation of Steel Products' Life Cycle
With the effect
of
sustainable development strategy spread increasingly, peo-
ple's value view to commodity is changing. At the same time, people's definition
to quality is also profound quickly.
It is concluded that the quality not only relates
to optimization
of
technology and an optimal usage, but also to the system opti-
mization
of
debt, such as investment cost, and fund recovery rate (Walter, 2007).
On conception
of
function and time, the quality should be defined as a long-term
system function optimization. As comes to value view to commodity, the funda-
mental meanings should include both the strong market competitiveness, and the
sustainability
of
development.
9.1.3 Features and multi-levels
of
the influence
of
steel plants on
environment
All kinds
of
emissions that caused by steel production have a multi-level effect on
environment (Yin, 1997). Generally speaking, industrial exhaust emission will
affect the regions even to the worldwide, such as CO
2
,
SOx, and NO
x
and so on.
These substances, to large extent, have a cumulative effect on the green house gas
emission and the acid rains. Wastes such as sewage, waste liquid, waste slurry
caused in manufacture process will have a great effect on drainage basin, under-
ground water, even oceans. While various slag, sludge, dust, steel scrap, noise,
vibration, and scintillation, at large extent, will influence living and healthy
of
the
operators and the related community residents, even to a regional system. To pol-
lution
of
different type and emission from different level, their zones affected are
different so their countermeasures are different, too.
9.2 Progress
of
Environment Protection in Steel Enterprises
Worldwide
From the development progress
of
environment protection around the steel enter-
Chapter9 SteelPlantsandthe Environment Issues
295
prises, it can be seen that this is a gradually improved cognition. The related coun-
termeasure changed from the end-pipe treatment to relatively initiative precaution,
dispose, assimilation and recycling (Fig. 9.3). In the whole, it experienced four
stages as following (Yin, Zhang, Lu, et al, 2002):
pOllutjO~
treatmJnt I . I .
I.
I.
Energy
savmgandermssionreduction
.L
.L,
Ld
greenmanufacturing
.)
. 1 hi. I I .
Eoo-mr
tna
ern
and7
source
r~CYChng
1960 1970 1980
Year
1990 2000 2010
Fig. 9.3
The
Sketch
of
progress
of
environmental
protection
around
steel
enterprises
worldwide
1. From 1960s to1970s: pollution treatment stage. Because developed countries
had a long history
of
steel industry, the problem
of
public hazard pollution was
exposed early. So their cognition to protect environment was earlier, too. At that
stage, they adopted measures such as dilution discharge and end-pipe treatment.
Therein, the purpose
of
use end-pipe treatment is to lower the concentration
of
contamination to meet the need
of
emission regulation by using high efficient
equipment and technology. But this method is only to transfer the contamination
from here to there, or among different mediums .At the same time, overmuch end-
pipe treatment would increase the economical burden in enterprise and society,
even affect their self-developing motivity.
2. From 1970s to 1990s: energy saving stage (the stage
of
sources treatment
of
emission). The oil crisis which broke out in 1973 made western countries realized
the importance
of
energy, so they started to adopt various methods to reduce en-
ergy consumption. Decrease in specific energy consumption as well as small con-
sumption, small emission and big productivity. may be realized through enevgy
saving As a matter
of
fact, it can reduce all kinds
of
emissions from their sources.
It
should say that is an efficient, relative initiative strategy. Long-term practice
indicated that energy saving is an active, economical measure to protect environ-
ment.
It decreased the expenditures
of
environment protection; meantime, it also
got economical and environmental benefit. Generally speaking, energy saving is
the key point
of
environmental protection that promoting with environment pro-
tection, they are closely related .
3. From late 1980s to 1990s: the stage
of
cleaner production and green manu-
facturing (active source treatment). Cleaner production is the strategy given by
generalization
of
the experiences and the lessons
of
industrial pollution and its
296
Metallurgical Process Engineering
treatment. Cleaner production advocates high efficiency
of
resource using to re-
duce or prevent the emission
of
pollutant and poisonous substance from the
source. So it can realize the purpose
of
environmental protection while guarantee-
ing the economical benefit. Obviously, cleaner production puts entirety, precau-
tionary and sustainable environment strategy into the manufacture process, prod-
ucts and their service. Compared with the end-pipe treatment, cleaner production
is changed from simplex, passive pollution control phase to the stage
of
overall,
initiative precaution and reduction
of
the pollution. The connotation
of
green
manufacturing is more extensive than cleaner production; it includes the im-
provement
of
products' using efficiency, the prolongation
of
life span, the waste
management for recovery and recycling.
It also related to products' full life cycle
assessment
of
environmental burden.
4. Later 1990s: the stage
of
studying eco-type reforming
of
steel plant and en-
tering into circular economy society. The aim is forming the eco-industrial chain
through the combination
of
the steel enterprise with the processes
of
related pro-
duction, the products' consumption, abandoning, decomposition, reuse and recy-
cle. This is an important thought and symbol that indicates the steel industry eco-
type reforming and entering into the circular economy society.
9.3 Green Manufacturing in Steel Plants
With the demands
of
sustainable development, environmental protection has new
progress in the field
of
research and practice. The "eco-Iabel" is applied to ex-
press the environmental information and the environmental burden
of
products.
The life cycle assessment is also used to compare the environmental performance
among products. The cleaner production becomes mainstream technologies. The
green manufacturing process, even the eco-industrial chains are developing. The
environmental performance in enterprise is improved with establishment
of
the
environmental management system and the environmental management standards
of
ISO14000 are established to promote the sustainable development in the future
all over the world.
9.3.1 Concept and connotation
of
green manufacture
We should pay great attention to green manufacturing. Nowadays, people all over
the world have recognized the concept
of
"large manufacture".
It
almost includes
all manufacturing industries such as metallurgical, chemical, architectural and
mechanical industry etc.. Therefore, green manufacturing will certainly involve in
the operation, development, reforming and breakthrough
of
all manufacturing
industries.
Because
of
the short history
of
growth
of
the green manufacturing, today there
Chapter 9 Steel Plants and the Environment Issues
297
is still no unitary definition about it. The concept and connotation are still in the
exploratory stage. According to the viewpoint in the blue book from the Society
of
Manufacturing Engineers, USA (Mclogk, et ai, 1996) it can be seen that green
manufacturing is a modern manufacturing pattern with comprehensively thinking
about the resource and energy consumption and the environmental impact.
It
aims
to make least negative effect and highest resource utilization on the full product
life cycle from design, processing, package, transportation, using, abandoning to
recycling.
It
will also optimize the economic efficiency, the environmental and the
social benefits
of
the enterprises.
The main concepts
of
green manufacturing:
I. We should take measures to control the origin
of
pollution in the manufac-
ture process from source and pay great attention to the green life cycle
of
products.
2. The pollutant should be eliminated inside the process
of
manufacture and the
economic efficiency and environmental benefits should be coordinated.
3. The eco-industrial chain should be formed among different types and related
enterprises to promote the "zero" emission system (also named as minimum emis-
sion system).
4. The so-called pollution refers to the exogenous pollution that is above the
acceptance ability
of
the system eco-balance in different scales.
5. The incessant integration prevention strategy about environmental pollution
is stressed, and the optimum mode
of
sustainable development strategy is pursued.
There are different standpoint even incomplete uniform concept between the
green manufacturing and the end-pipe treatment. The end-pipe treatment is related
to the treatment
of
environment that has already been polluted. The aim is to re-
covery or near to recovery the environment back to the original that is not pol-
luted. This always leads to the higher business cost; even weaken the market
competitiveness. However, the green manufacturing lays emphasis on strategy
preventing the pollution from the source, but it not negates the end-pipe treatment.
Attention to the green manufacturing should be paid from the fundamental rules,
the process technology and engineering to developing the environment-friendly
process (including selection
of
raw materials and energy, their alternative and
substitute etc.), technical equipment, manufacturing process, eco-products and
their use phase etc. Based on these breakthrough technologies the paradox be-
tween environmental pollution and sustainable development would be solved.
9.3.2 Philosophy
and
technical route
for
green manufacture
A. The consideration
of
green manufacturing
Green manufacturing certainly has multi-scale and multi-level connotation be-
cause the formation and solution
of
environmental problems are developed in