IRON AND STEEL IN EUROPEAN UNION

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IRON AND STEEL IN EUROPEAN UNION

• By
• Rubén Robles
• J. Clemente Elices
• Ángel Cobo
• 12-7-2007

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GENERAL INFORMATION

• Ancient steel.
• Woortz steel produced in India and Sri Lanka
  from around 500 year BC was produced in a wind
  furnace, blown by the monsoon winds. In the 4th
  century BC Steel weapons like the Falcata were
  produced in the Iberian peninsula. Crucible steel
  was produced in mery by 9th century AD

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GENERAL INFORMATION

• STEEL NOW
• Iron and steel are important products that are
  widely used. The production of crude steel in the
  European Union stood at 155.3 million tonnes in
  1999, equivalent to about 20 of world

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GENERAL INFORMATION
The apparent steel consumption per capita in the
EU in 1995 was 367 kg/capita
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GEOGRAPHICAL DISTRIBUTION OF STEEL IN THE EU
The most steelworks are localice in the center of
europe Germany is the country with most
steelworks, Producing 40 millon tonnes of crude
steel in 1996
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GEOGRAPHICAL DISTRIBUTIONOF STEEL IN EU
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REST OF WORLD (2006) CIFRES
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STRUCTURE OF THE IRON AND STEEL BREF

• Sinter plants
• Pelletisation plants
• Coke oven plants
• Blast furnaces

• Basic oxygen steelmaking
• Electric arc furnace steelmaking

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BASIC OXYGEN STEELMAKING

• Accounting for 60 of the world's total output of
  crude steel, the Basic Oxygen Steelmaking process
  is the dominant steelmaking technology
• The primary raw materials for are 70-80 liquid
  hot metal from the blast furnace and the balance
  is steel scrap
• These are charged into the Basic Oxygen Furnace
  (BOF) vessel
• Oxygen (99.5 pure) is "blown" into the BOF at
  supersonic velocities. It oxidizes the carbon and
  silicon contained in the hot metal liberating
  great quantities of heat which melts the scrap.

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BASIC OXYGEN STEELMAKING

• The product is molten steel.
• From here it may undergo further refining in
  a secondary refining process or be sent directly
  to the continuous caster where it is solidified
  into semifinished shapes blooms, billets, or
  slabs.

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BASIC OXYGEN STEELMAKING
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BOF-BAT

• Process-integrated measures
• PI.1 Energy recovery from the BOF gas
• PI.2 Lowering the zinc-content of scrap
• PI.3 On-line sampling and analysis of steel
• End-of-pipe techniques
• EP.1 Primary de-dusting
• EP.2 Particulate matter abatement from pig iron
  pre-treatment
• EP.3 Secondary de-dusting
• EP.4 Dust hot-briquetting and recycling
• EP.5 Treatment of wastewater from wet de-dusting
• EP.6 Treatment of wastewater from continuous
  casting

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BOF-BAT

• PI.1 Energy recovery from the BOF gas
• Generally, two systems can be used to recover
  energy from the BOF gas
• Combustion of BOF gas in the converter gas duct
  and subsequent recovery of the sensible heat in a
  waste heat boiler.
• Suppression of BOF gas combustion and storage of
  the BOF gas in a gasholder for subsequent use.

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BOF-BAT

• PI.2 Lowering the zinc content of scrap
• A high zinc content in the blast furnace
  has an adverse affect on correct operation. This
  zinc mainly originates from the scrap charged
  into the basic oxygen furnace. The release of Zn
  can fluctuate strongly from one cast to another.
  The same problem, but to a lesser extent, applies
  to lead (Pb) or cadmium (Cd).

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BOF-BAT

• PI.3 On-line sampling and steel analysis
• Oxygen steelmaking is a batch process. In
  order to monitor progress samples are taken from
  the steel bath for analysis. It used to be
  necessary to interrupt oxygen blowing and tilt
  the BOF in order to take the sample. This was a
  time consuming process and it increased emissions
  from the BOF. In a modern plant samples are taken
  on-line during oxygen blowing by means of a
  sub-lance.

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BOF-BAT

• EP.1 Primary de-dusting
• During oxygen blowing, BOF gas is
  generated.This gas is loaded with a large amount
  of particulate matter. The BOF gas is recovered
  for use as a fuel. Primary de-dusting is usually
  performed by venturi-type scrubbers
  (approximately 90 of the plants) or dry
  electrostatic precipitators. Prior to the venturi
  or the ESP, coarse particulates are usually
  removed by means of a deflector

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BOF-BAT

• EP.2 Particulate matter abatement from pig iron
  pre-treatment

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BOF-BAT

• EP.3 De-dusting of secondary off-gases
• Secondary off-gases result from following
  operations
• - reladling and deslagging of hot metal
• - BOF charging
• - tapping of liquid steel and slag from BOF
  (converters) and ladles
• - secondary metallurgy and tapping operations
• - handling of additives
• - continuous casting

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BOF-BAT

• EP.4 Dust hot-briquetting and recycling with
  recovery of high Zn concentrated pellets for
• external
• reuse.

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BOF-BAT

• EP.5 Treatment of wastewater from wet de-dusting
• In most oxygen steelmaking plants, scrubbers
  are used to reduce emissions to air from the
  primary gas flow. This potentially transfers
  pollution from air to water so the wastewater
  generated is usually recycled and treated before
  discharge. The water from the scrubbers mainly
  contains suspended solids Zinc and lead being
  the main heavy metals present.

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BOF-BAT

• EP.6 Treatment of wastewater from continuous
  casting.

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EMERGING TECHNIQUES-BOF

• The following techniques have been identified as
  emerging techniques
• - Near net-shape casting and horizontal casting
• - Processing of Zn-rich sludges/dusts
• - New reagents in the desulphurisation process
• - Application of foaming techniques in pig iron
  pre-treatment and steel refining
• - Replacing air above the hot metal by inert
  gases (CO2, N2).

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ELECTRIC STEELMAKING
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ELECTRIC STEELMAKING

• The direct smelting of iron-containing materials,
  such as scrap is usually performed in electric
  arc furnaces (EAF) which play an important and
  increasing role in modern steel works concepts
• Today the percentage of electric arc furnace
  steel of the overall steel production in the EU
  are 35.3 .
• In Italy and Spain the production of electric
  arc furnace steel higher than steel production
  via the blast furnace-basic oxygen furnace route.

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ELECTRIC STEELMAKING

• For the production of carbon steel and
  low/hight alloyed steels, following main
  operations are performed
• Raw material handling and storage
• Furnace charging with/without scrap preheating
• EAF scrap melting
• Steel and slag tapping
• Ladle furnace treatments for quality adjustment
• Slag handling
• Continuous casting

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ELECTRIC STEELMAKING-BAT

• Process-integrated measures
• PI.1 EAF process optimisation
• PI.2 Scrap preheating
• PI.3 Closed loop water cooling system
• End-of-pipe techniques
• EP.1 Advanced emission collection systems
• EP.2 Efficient post-combustion in combination
  with advanced off gas treatment
• EP.3 Injection of lignite coke powder for off gas
  treatment
• EP.4 Recycling of EAF slags
• EP.5 Recycling of EAF dusts

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ELECTRIC STEELMAKING-BAT

• PI.1 EAF process optimisation

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ELECTRIC STEELMAKING-BAT

• PI.2 Scrap preheating

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ELECTRIC STEELMAKING-BAT

• PI. 3 Closed loop water cooling system
• The most relevant use of water considered here
  is the water used for the cooling of the elements
  of the furnace. Additionally, some water may be
  used for the cooling of waste gas or in the
  secondary metallurgy section.

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ELECTRIC STEELMAKING-BAT

• EP.1 Advanced emission collection systems
• The primary and secondary emissions to air are
  of high relevance. The available abatement
  techniques should be fed with the raw emissions
  as complete as possible. Thus the collection of
  the emissions is important. The combination of
  4th hole (in case of three electrodes)
  respectively of 2nd hole (in case of one
  electrode) direct extraction with hood systems
  (or furnace enclosure) or total building
  evacuation are the most favorite systems.

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ELECTRIC STEELMAKING-BAT

• EP.2 Efficient post-combustion in combination
  with advanced off gas treatment
• Post combustion in the furnace is developed to
  use a maximum of chemical energy of the CO in the
  furnace and to improve the energy balance, but CO
  and H2 are never completely oxidised in the
  furnace for this reason, it needs post
  combustion.

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ELECTRIC STEELMAKING-BAT

• EP.3 Injection of lignite coke powder for off gas
  treatment
• In order to reduce organic micropollutants in
  the total off gas (primary and secondary
  emissions), especially PCDD/F lignite coke powder
  can be dosed to the duct beforem the bag filters.

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ELECTRIC STEELMAKING-BAT

• EP.4 EAF slag recycling
• EAF slag can be regarded as an artificial
  rock, similar to natural rock, consisting of
  iron-oxides (FeO), lime (CaO), silicium-oxide
  (SiO2), and other oxides (MgO, Al2O3, MnO) EAF
  slags are characterised by high strength, good
  weathering resistance, and also high resistance
  against polishing. They also have properties,
  that make them suitable for use in hydraulic
  engineering.

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ELECTRIC STEELMAKING-BAT

• EP.5 EAF dust recyling
• There are two method of dust recycling
• Recycling of precipitated dusts
• Zinc recovery and removal of heavy metals

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EMERGING TECHNIQUES-EAF

• Scrap sorting
• New furnace concepts
• Comelt EAF
• State of Development / Realisation
• Contiarc furnace

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FURTHER READING

• www.worldsteel.com
• www.aceralia.es
• www.wikipedia.com