Iron and steel industry

1. Eng. Amira Abdelraheem Mohamed
Dr. kamal Noweir

2. Iron is a lustrous, silvery soft metal. It is extracted from iron ore, and is almost never
found in the free elemental state. In order to obtain elemental iron, the impurities must
be removed by chemical reduction.
Iron is the main component of steel
Steel is a metal composed of iron plus varying
amounts of carbon as well as other elements such
as chromium, nickel, molybdenum, vanadium.

3. Iron & Steel Production Process
Currently, two processes dominate the global steel production. These
may be generally be described as:
the integrated steel mill,
where steel is made by
reducing iron ore in a blast
furnace to make pig
iron which is subsequently
processed in an oxy-steel
plant; and
the minimal, in which steel is
made by melting scrap or
scrap substitutes in an
electric arc furnace
(EAF).

4. Raw material
IRON ORE / SCRAP
COKING COAL
LIMESTONE
Iron & Steel Production Process Phases
Step 1:
Treatment
of raw
materials
Step 2:
Iron
making
Step 3:
Steel
making
Step 4:
Casting
Step 5:
Rolling
and
finishing

6. Step 1: Treatment of raw materials :
which consists of
Coke production
sinter production
Pelletisation
Scrap Screening and cleaning

7. Step 1: Treatment of raw materials : which consists of
How to produce:
• the raw coal obtained by crushing and blending is charged into the coke
chamber, where it is then carbonized by indirect heating at 1,473-1,573K
for 14-18 hours to form coke that contains about 90% fixed carbon.
Role in production process:
• Coke production is an important part of the integrated iron and steel
plants using BF-BOF route, acting as a reducing agent, as a source of
thermal energy, and providing physical support for the burden in blast
furnace.
Coke production

9. Step 1: Treatment of raw materials : which consists of
How to produce:
• a blend of different ores, ferrous containing materials – such as flue
dust – and fine coke particles (known as coke breeze) is deposited on a
large travelling grate.
• As the grate moves, air is sucked from the top through the mixture,
enabling combustion through the entire layer and complete sintering –
where the temperatures may reach 1300 – 1480 oC. At the end of the
strand, the material is cooled by air and finished sinter is size-screened.
sinter production
Role in production process:
The purpose of the sinter plant is to process fine grained raw materials into
a coarse grained iron ore sinter, ready to be charged to the blast furnace.
sinter – is necessary to improve the permeability of the burden, making
reduction easier. which reduces the intensity of blast furnace operations and
reduces coke demand.

10. Sintering
Process
Coke Breeze
fuel
Sinter (used in
Pig Iron Production)
Iron Ore

11. Step 1: Treatment of raw materials : which consists of
Pellets are formed from iron-containing raw materials (i.e., fine ore and
additives) into 9–16 mm spheres in a very high temperature process. The
process includes grinding, drying, balling, and thermal treatment of the raw
materials.
Pelletisation, Screening and cleaning
Scrap Screening and cleaning

12. STEP 2: IRON MAKING
Blast furnace
Direct Reduced Iron
Molten iron Can be produced by

13. Carbon is supplied to the blast furnace mainly in the form of coke
produced from metallurgical grade coking coal.
Carbon serves a dual purpose in the iron making process, primarily as a
reducing agent to convert iron oxides to iron but also as an energy source
to provide heat when carbon and oxygen react exothermically.
Step 2: Iron making
Blast furnace

14. Blast
furnace
slag
Raw materials
Purchased coke; Scrap Iron;
Iron Ore; Pellets; Sinter;
Tar; Oil; Dolomite; Limestone
fuel
Integrated
Coke Oven
Plant
Coke
Coke Oven Gas
Coal tar, light oil
Pig Iron
(transferred to
Steel mill or off-site
Blast Furnace Gas
(burned onsite, transferred
to coke oven or off-site)

15. Step 2: Iron making
DRI
In Direct Reduced Iron (DRI), also known as Sponge Iron, iron ore is reduced
in its solid state
DRI production is common in Middle East, South America, India and Mexico.
Natural gas and coal are the two primary fuels used in DRI production.

16. DRI processes can be divided up by the type of reactor
employed, namely:
Shaft Furnaces
Rotary Kilns
Rotary Hearth Furnaces
Fluidized Bed Reactors
Most
common

17. Step 3: steel making
Basic oxygen furnace
Electric arc furnace
Molten steel Can be produced by

18. Basic Oygen Furncace (BOF) is
a pear shaped vessel where the
pig iron from blast furnace, and
ferrous scrap, is refined into
steel by injecting a jet high-
purity oxygen through the hot
metal.
Basic oxygen furnace

19. Electric arc furnace
Electric Arc Furnaces (EAFs) are a central part of the production.
EAFs are used to produce carbon steels and alloy steels primarily by
recycling ferrous scrap. Where EAFs is to convert the solid raw materials to
liquid crude steel as fast as possible and then refine further in subsequent
secondary steelmaking processes.
The iron units are loaded in a basket together with limestone – for slag
formation – and charged into the furnace. The scrap is melted and converted
into high quality steel by using high-power electric arcs.

21. Step 4: CASTING
A wide variety of processes that can be part of finishing are grouped
under casting and shaping (rolling).
Casting is a stage in finishing operations where the hot metal with the
right properties is turned into intermediate, marketable products.
Casting can be done as a batch (producing ingots) or continuous
(producing slabs, blooms or billets) process.
In most mills, casting is performed in continuous casting machines.

22. continuous casting, in
which billets or slabs
are cast direct from
molten metal and it is
not only saves time and
energy but also
improves the quality
of the steel and
increases the yield.
Moreover, the process is
more controllable.

23. Ingot casting : it is a
method of pouring
molten steel into molds
to produce ingots which,
when solidified, are
reheated and rolled into
slabs or billets.

24. Step 5: Rolling and finishing
Hot rolling
mill
This step can be:
Bar, rod,
structural and
tubing mills
Steel from casting process
Wire Bars Rods
Structural shapes
Rails Pipe Tubing
Blooms Billets
Cold rolling
mill
Treatment &
finishing
Cold-rolled sheet
Strip Plate Pipe
Hot -rolled
sheet

25. ROLLING MILL

26. Occupational hazards in iron & steel
Operations in the iron and steel industry may
expose workers to a wide range
of hazards or workplace activities or conditions that
could cause incidents, injury, death, ill health or
diseases. These are discussed as follow.
General hazards
Specific hazards
In each step

27. slips, trips and
falls on the
same level
falls from height
unguarded machinery
falling objects;
working in confined spaces
moving
machinery, on-
site transport,
forklifts and
cranes
exposure to
controlled and
uncontrolled
energy sources
exposure to
asbestos
exposure to
mineral wools and
fibres
inhalable agents (gases,
vapours, dusts and fumes)
skin contact with
chemicals
contact with hot metal
fire and explosion
extreme temperatures
radiation
noise and vibration
electrical burns and electric shock
manual handling and repetitive work;
ergonomics
lack of OSH training
poor work organization
General hazards

28. Physical hazards
1. Noise
To control
Hearing conservation programs include periodic noise and hearing
assessments, noise control engineering and maintenance of machines
and equipment, personal protection, and worker education and training
must be applied
Steel making is one of the noisiest industries & The
major sources include
*fume extraction systems, *vacuum systems using steam ejectors,
*electrical transformers *the arc process in electrical arc *furnaces, rolling
mills * the large fans used for ventilation.

29. Physical hazards
2. Vibration
Potentially hazardous vibration is created by oscillating mechanical
movements, most often when machine movements have not been
balanced, when operating shop floor machines and when using such
portable tools as pneumatic drills and hammers, saws and grindstones.
Damage to vertebral discs, low back pain and degeneration of the spine
have been attributed to whole body vibration in a number of studies of
overhead crane operators

30. Heat exposure is a problem throughout the iron and steel industry,
especially in plants located in hot climates.
Recent research has shown that, contrary to previous belief, the highest
exposures occur during forging, when workers are monitoring hot steel
continuously, rather than during melting, when, although temperatures are
higher, they are intermittent and their effects are limited by the intense
heating of the exposed skin and by the use of eye protection.
It can be controlled by
The danger of heat stress is reduced by adequate fluid intake, adequate
ventilation, the use of heat shields and protective clothing, and periodic
breaks for rest or work at a cooler task.
Physical hazards
3. Heat exposure

31. The accidental or careless inclusion of radioactive materials in the scrap
steel being recycled.
To prevent this,
many plants are using sensitive radiation detectors to monitor all scrap
before it is introduced into the processing.
Physical Hazards
4. Radiation

32. Steel workers may be exposed to a wide range of pollutants depending on
the particular process, the materials involved and the effectiveness of
monitoring and control measures.
Adverse effects are determined by the physical state of the pollutant
involved, the intensity and duration of the exposure, the extent of
accumulation in the body and the sensitivity of the individual to its effects.
Chemical Hazards
Airborne Pollutants

33. 1. Dust and fumes
Emissions of fumes and particulates are a major potential problem for
employees working with molten metals, making and handling coke, and
charging and tapping furnaces. They are also troublesome to workers
assigned to equipment maintenance, duct cleaning and refractory wrecking
operations.
Health effects are related to the size of the particles (i.e., the proportion that
are respirable) and the metals and aerosols that may be adsorbed on their
surfaces. There is evidence that exposure to irritant dust and fumes may also
make steelworkers more susceptible to reversible narrowing of the airways
(asthma) which, over time, may become permanent.

34. Exposures to silica, with resultant silicosis, once quite common among
workers in such jobs as furnace maintenance in melting shops and blast
furnaces, have been lowered through the use of other materials for furnace
linings as well as automation, which has reduced the number of workers in
these processes.
Asbestos, once used extensively for thermal and noise insulation, is now
encountered only in maintenance and construction activities when formerly
installed asbestos materials are disturbed and generate airborne fibres.
A recent cross-sectional study found in 20 out of 900 steelworkers (2%),
much of which was diagnosed as restrictive lung disease characteristic of
asbestosis.
2. Silica
3. Asbestos

35. • Emissions generated in steel making may contain heavy metals (e.g., lead,
chromium, zinc, nickel and manganese) in the form of fumes, particulates,
and adsorbates on inert dust particles.
• They are often present in scrap steel streams and are also introduced in
the manufacture of special types of steel products.
• Research carried out on workers melting manganese alloys has shown
impaired physical and mental performance and other symptoms of
manganism at exposure levels significantly below the limits currently
allowable in most countries.
• Short-term exposure to high levels of zinc and other vaporized metals may
cause “metal fume fever”, which is characterized by fever, chills, nausea,
respiratory difficulty and fatigue.
4. Heavy metals

36. • Acid mists from pickling areas can cause skin, eye and respiratory
irritation.
• Exposure to hydrochloric and sulphuric acid mists from pickling baths
have also been associated in one study with a nearly twofold increase in
laryngeal cancer.
5. Acid mists
6. Oil mists
• Oil mists generated in the cold rolling of steel can produce irritation of
skin, mucous membranes and upper respiratory tract, nausea, vomiting
and headache.
• One study reported cases of lipoid pneumonia in rolling mill workers who
had longer exposures.

37. 6. Sulphur compounds
• the predominant source of sulphur emissions in steel making is the use of
high-sulphur fossil fuels and blast furnace slag.
• Hydrogen sulphide has a characteristic unpleasant odour and short-term
effects of relatively low-level exposures include dryness and irritation of
nasal passages and the upper respiratory tract, coughing, shortness of
breath and pneumonia.
• Longer exposures to low levels may cause eye irritation, while permanent
eye damage may be produced by higher levels of exposure. At higher
levels, there may also be a temporary loss of smell which can delude
workers into believing that they are no longer being exposed.

38. • PAHs are produced in most combustion processes; in steelworks, coke
making is the major source.
• When coal is partially burnt to produce coke, a large number of volatile
compounds are distilled off as coal tar pitch volatiles, including PAHs.
These may be present as vapours, aerosols or adsorbates on fine
particulates.
• Short-term exposures may cause irritation of the skin and mucous
membranes, dizziness, headache and nausea, while long-term exposure has
been associated with carcinogenesis.
• Studies have shown that coke-oven workers have a lung cancer mortality
rate twice that of the general population. Those most exposed to coal tar
pitch volatiles are at the highest risk.
7. Polycyclic aromatic hydrocarbons

39. • Over 1,000 chemicals are used or encountered in steel making:
• as raw materials or as contaminants in scrap and/or in fuels; as additives in
special processes; as refractories; and as hydraulic fluids and solvents used in
plant operation and maintenance. Coke making produces by-products such as
tar, benzene and ammonia; others are generated in the different steel-making
processes.
• All may potentially be toxic, depending on the nature of the chemicals, the type,
the level and duration of the exposures, their reactivity with other chemicals
and the susceptibility of the exposed worker.
8. Other chemicals

40. • Vanadium and other alloy additions may cause chemical pneumonitis.
• Carbon monoxide, which is released in all combustion processes, can
be hazardous when maintenance of equipment and its controls are
substandard.
• Benzene, along with toluene and xylene, is present in coke-oven gas
and causes respiratory and central nervous system symptoms on acute
exposure; long-term exposures may lead to bone marrow damage,
aplastic anaemia and leukaemia.
• Accidental heavy exposures to fumes containing sulphur dioxide and
nitrogen oxides have caused cases of chemical pneumonitis.

41. Specific
hazards
Special Hazards In Coke Production Step
Special Hazards In Iron and steel-making Step
Special Hazards In Surface preparation / rolling &
finishing Step

42. PRODUCTION STEP
• Coke oven emissions contain cancer-causing polynuclear aromatic
hydrocarbons, along with toxic gases and vapours such as benzene,
hydrogen sulphide, carbon monoxide and ammonia.
• Workers in the coal preparation plant are exposed to coal dust, which
can cause lung damage.
• Coke ovens must be kept hot to maintain their structural integrity, so
production and maintenance operations pose the risk of heat stress.
HEALTH
HAZARDS

43. • mobile equipment, burns, fire and explosion can be included in this step.
• Coke production are served by large tracked mobile equipment,
including larry, cars used in charging, pusher machines used to remove
the coke, and door machines used to remove the oven doors when the
coke is ready to be pushed.
• Visibility can be poor if emissions are badly controlled.
• Workers can suffer severe burns if they come into contact with hot coke,
doors or jambs.
• Coke oven gas is flammable and explosive, as are many of the chemicals
collected in by-product plants.
SAFETY
HAZARDS

44. CONTROL
1. Coke oven doors, jambs and other equipment should be designed so as to
minimize the occurrence and magnitude of leaks.
2. Leaks from coke oven doors, lids, and other equipment should be
eliminated or
reduced through a comprehensive operation and maintenance program
designed for that purpose.
3. Leaking doors and jambs should be identified through a 24-hour inspection
program, and repaired at the conclusion of the coking cycle. Other leaks
should be eliminated as soon as practicable.
5. Sealants for doors, lids and other equipment should be free of asbestos and
other hazardous materials.

45. 6. Larry cars, pusher machines, door machines and similar equipment
should be operated from enclosed cabs equipped with filtered, conditioned
air systems.
7. Coke by-product workers should receive regular medical surveillance,
particularly focusing on the early detection of leukemia and other blood
disorders caused by benzene, with appropriate follow-up.
8. A respiratory protection program should be instituted for workers
exposed to benzene or other hazardous substances above the relevant
exposure limits.
9. A program should be instituted to ensure that explosive atmospheres are
not created in equipment that transports coke oven gas and other flammable
materials.

46. 10. Alarms should be installed in all areas where coke oven gas might build
up in a release.
11. Workers exposed to hot surfaces or radiant heat from open ovens should
be provided with appropriate protective equipment, and covered by a heat
stress prevention program.
12. When maintenance is performed on or near mobile coke oven machines,
the machines should be locked out
13. Mobile coke oven machines should be designed for safe entry and exit,
and provided with travel alarms.
14. Clean air stations with appropriate ambient temperature control should
be designated or provided for workers in regulated areas, where they can
take breaks

47. The iron and steel industry uses a range of furnaces &
the main hazards.
Special Hazards In Iron and steel-making Step
1. water coming into contact with molten metal. The water may be present in
scrap material, damp molds, from leaks in the furnace cooling systems or leaks
in the building.
2. ignition of volatile materials and fuels.
fires and explosions hazards
which is results from
fires and explosions hazards
can cause unlimited losses

48. The iron and steel industry uses a range of furnaces.
• Furnaces may cause glare that can injure the eyes
• Manual operations, such as furnace bricklaying, and hand-arm vibration
from using pneumatic tools and grinders may cause ergonomic problems..
• Huge emissions of dust, fumes and poisoning gases like CO.
• Ultraviolet (UV) and/or infrared during visual inspection of furnaces.
• molten metal burns
• All physical & chemical hazards mentioned before

49. • Molten slag and metal should be prevented from coming into contact with
water, which will cause a steam explosion.
Manual operations, such as furnace bricklaying, and hand-arm vibration from
using pneumatic tools and grinders may cause ergonomic problems..
• Huge emissions of dust (crystalline silica dust from shakeout and fettling)
fumes and poisoning gases like CO.
• Ultraviolet (UV) and/or infrared during visual inspection of furnaces.
• molten metal burns
• All physical & chemical hazards mentioned before
The iron and steel industry uses a range of furnaces.

50. 1. Suitable eye protection is provided and worn to protect eyes against glare.
2. There should be suitable and sufficient general and local exhaust ventilation
with dust- and fume-collecting devices.
3. Ultraviolet (UV) and/or infrared light-resistant goggles or face shields
should be provided where there is a requirement for the authorized visual
inspection of furnaces.
4. Continuous detectors should be installed to provide early warning of raised
levels of dangerous gases.
5. People working in and around the furnace and oven areas should be
provided with suitable PPE to protect them against molten metal burns,
noise, and physical and chemical hazards
6. Furnaces operators should be trained in safe systems of work.
7. Refractories (e.g. crucibles, troughs, ladles) and tools should be preheated
and dried before use to minimize the risk of explosion.
8. Furnaces should not be operated beyond their safe lives.
CONTROL

51. 9. Personnel handling molten metal should have been trained in the proper
procedures to adopt, and in the relevant safety and health precautions,
including use of appropriate PPE.
10. Before each filling, the pouring of, or transport of slag ladles and their
related appliances should be visually inspected.
11. Ladles should not be overfilled.
12. Ladles and other equipment used on molten metal should be dry and,
ideally, preheated before use.
Specific PPE should include, but not be limited to:
(a) molten metal resistant jackets and trousers;
(b) face shields or vented goggles; (c) molten metal resistant gloves;
(d) safety footwear insulated against heat;
(e) respiratory protective equipment; (f) protective helmets;
(g) hearing protection; and (h) eye protection.

52. Various methods are used to remove defects, scale, oxides, and other
impurities from the surface of steel at different points in the process. These
include:
(a) scarfing, which uses fixed or hand-held torches or lances to burn away the
impurities; Which may expose workers to metal fumes and dust, noise, and
burns from scarfing lances
(b) surface grinding; generates dust, and
involves machinery hazards.
(c) degreasing, which uses detergents or solvents to remove grease; Degreasing
solvents may be toxic.
(d) pickling, which uses acids or hydrogen peroxide to dissolve scale and
oxides. Acids can cause acid burns.
Surface preparation processes & hazards
Special Hazards In Surface preparation / rolling &
finishing Step

53. • Scarfing and surface grinding should be done in enclosures
• Workers should be provided with respiratory protection where the
ventilation does not reduce exposure to levels below the appropriate
exposure limits.
• Workers who handle pickling acids or hydrogen peroxide should be
provided with acid or chemical-resistant clothing, goggles and face shields,
footwear and leggings, and respiratory protection where necessary.
• acid pickling tanks and solvent degreasing tanks should be covered, and
provided with exhaust ventilation to control the vapors.
Surface preparation hazards control

54. • there is a risk of trapping between the rolls
• Severe injuries may be caused by shearing, cropping, trimming and
guillotine machines, unless the dangerous parts are securely guarded.
• The use of large quantities of oils, rust inhibitors and so on, which are
generally applied by spraying, is one of the hazards commonly
encountered in sheet-rolling mills.
• In hot-rolling, burns, eye injuries or other injuries may be caused by flying
mill scale and dust particles or by whipping of cable slings. Eyes may also
be affected by glare.
• Cuts may occur when workers contact the edge of thin steel sheets or strip.
• When lead-alloyed steel is rolled or cutting-off discs containing lead are
used, toxic particles may be inhaled.
Rolling mill hazards
Special Hazards In Surface preparation / rolling &
finishing Step

55. • secure guard must be found to avoid trapping, trimming & shearing.
• Wear the necessary PPE.
• necessary constantly to monitor lead concentrations at the workplace
When lead-alloyed steel is rolled
• An effective lockout/tag out program should be planned, implemented and
monitored for maintenance and repair.
Rolling mill hazards control

56. • Coating lines apply different types of materials to the surface of steel. They
include, but are not limited to, zinc, zinc alloy, tin, chromium and plastic,
in the form of liquids, powders, solids or molten metals.
Coating lines process & hazards
Special Hazards In Surface preparation / rolling &
finishing Step
Mainly Chemical Hazards

57. • Guards, railings, enclosures and signs should be used to protect production
and maintenance personnel from dangers such as chemical baths, hot
surfaces and molten metal.
• Worker education and training is essential.
• Workers should be provided with the appropriate PPE.
• Material safety data sheets should be provided for hazardous chemicals.
• local exhaust ventilation that is strategically placed to draw the
contaminants away from the worker.
Coating lines hazards control

58. • In heat treating, steel products are heated and cooled in a controlled way
to change their physical or mechanical properties without changing their
shapes.
Heat treating process & hazards
Special Hazards In Surface preparation / rolling &
finishing Step
• Hazards in heat treatment include burns and scalding, mechanical hazards
from steel handling, and hazards arising from the annealing gases,
including nitrogen, hydrogen and carbon monoxide. Furnace insulation
wools can expose workers to hazardous fibers.

59. • Inert annealing gases should be handled in a way that prevents their build-
up in enclosed spaces other than the furnace itself, so as to prevent
asphyxiation.
• The system for handling flammable annealing gases like hydrogen should
minimize the possibility of an explosive build-up.
• Use insulation wools with a low content of respirable fibers, and which do
not convert to silica when heated.
Heat treating hazards control

60. • Internal transport, such as road and rail vehicles used in the transport of
raw materials, intermediates, products, waste and people, has the potential
to cause injuries to workers and other people, as well as damage to the
workplace environment..
Internal transport process & hazards
Special Hazards In Surface preparation / rolling &
finishing Step

61. • Transport routes should be clear of obstructions
• The safe operating speed for vehicles should be posted and enforced.
• Operators of vehicles should receive and maintain adequate training.
• Operators should have the necessary knowledge of the hazards and
potential risks concerning the transportation of cargo as molten metal
splashes.
• Contractors and other visitors should be appropriately instructed about
the hazards and potential risks.
• Loads should be lowered slowly and smoothly.
• Vehicles should be equipped with ventilated cabins to protect workers
from hazardous materials.
• Vehicles should be equipped with ventilated cabins to protect workers
from hazardous materials.
Internal transport hazards control

62. THANK YO