is there any specifications or standards to be used in the steel manufacturing process? (making steel?)?

Question

I need some reference material to back up steel's cool down temperature ( making steel), and time, and some specifications for floors to be built in steel mill areas. Thanks .

Answer 1

I'm sure. You should ask U.S. Steel this one. I'm CERTAIN that there's a %'age of iron, nickle, and other metals you should use in production of it, to ensure stability, and durablity of the final product.

Answer 2

Steel: Try American Iron and Steel Institute, ASME, or NIST
Concrete: American Concrete Institute.

Answer 3

327
Iron and Steel Manufacturing
Industry Description and Practices
Steel is manufactured by the chemical reduction
of iron ore, using an integrated steel manufacturing
process or a direct reduction process. In
the conventional integrated steel manufacturing
process, the iron from the blast furnace is converted
to steel in a basic oxygen furnace (BOF).
Steel can also be made in an electric arc furnace
(EAF) from scrap steel and, in some cases, from
direct reduced iron. BOF is typically used for
high-tonnage production of carbon steels, while
the EAF is used to produce carbon steels and lowtonnage
specialty steels. An emerging technology,
direct steel manufacturing, produces steel
directly from iron ore. This document deals only
with integrated iron and steel manufacturing;
that on Mini Steel Mills addresses the electric arc
steel process and steel finishing processes. Steel
manufacturing and finishing processes discussed
in that document are also employed in integrated
steel plants. See also Coke Manufacturing.
In the BOF process, coke making and iron
making precede steel making; these steps are not
necessary with an EAF. Pig iron is manufactured
from sintered, pelletized, or lump iron ores using
coke and limestone in a blast furnace. It is
then fed to a BOF in molten form along with scrap
metal, fluxes, alloys, and high-purity oxygen to
manufacture steel. In some integrated steel mills,
sintering (heating without melting) is used to
agglomerate fines and so recycle iron-rich material
such as mill scale.
Waste Characteristics
Sintering operations can emit significant dust levels
of about 20 kilograms per metric ton (kg/t)
of steel. Pelletizing operations can emit dust levels
of about 15 kg/t of steel. Air emissions from
pig iron manufacturing in a blast furnace include
particulate matter (PM), ranging from less than
10 kg/t of steel manufactured to 40 kg/t; sulfur
oxides (SOx), mostly from sintering or pelletizing
operations (1.5 kg/t of steel); nitrogen oxides
(NOx), mainly from sintering and heating (1.2
kg/t of steel); hydrocarbons; carbon monoxide;
in some cases dioxins (mostly from sintering operations);
and hydrogen fluoride.
Air emissions from steel manufacturing using
the BOF may include PM (ranging from less than
15 kg/t to 30 kg/t of steel). For closed systems,
emissions come from the desulfurization step between
the blast furnace and the BOF; the particulate
matter emissions are about 10 kg/t of steel.
In the conventional process without recirculation,
wastewaters, including those from cooling
operations, are generated at an average rate of
80 cubic meters per metric ton (m3/t) of steel
manufactured. Major pollutants present in untreated
wastewaters generated from pig iron
manufacture include total organic carbon (typically
100–200 milligrams per liter, mg/l); total
suspended solids (7,000 mg/l, 137 kg/t); dissolved
solids; cyanide (15 mg/l); fluoride (1,000
mg/l); chemical oxygen demand, or COD (500
mg/l); and zinc (35 mg/l).
Major pollutants in wastewaters generated
from steel manufacturing using the BOF include
total suspended solids (up to 4,000 mg/l, 1030
kg/t), lead (8 mg/l), chromium (5 mg/l), cadmium
(0.4 mg/l), zinc (14 mg/l), fluoride (20 mg/l), and
oil and grease. Mill scale may amount to 33 kg/t.
The process generates effluents with high temperatures.
Process solid waste from the conventional process,
including furnace slag and collected dust,
is generated at an average rate ranging from 300
Pollution Prevention and Abatement Handbook
WORLD BANK GROUP
Effective July 1998
328 PROJECT GUIDELINES: INDUSTRY SECTOR GUIDELINES
kg/t of steel manufactured to 500 kg/t, of which
30 kg may be considered hazardous depending
on the concentration of heavy metals present.
Approximately, 65% of BOF slag from steel manufacturing
can be recycled in various industries
such as building materials and, in some cases,
mineral wool.
Pollution Prevention and Control
Where technically and economically feasible, direct
reduction of iron ore for the manufacture
of iron and steel is preferred because it does
not require coke manufacturing and has fewer
environmental impacts. Wherever feasible, pelletizing
should be given preferences over sintering
for the agglomeration of iron ore. The
following pollution prevention measures should
be considered.
Pig Iron Manufacturing
• Improve blast furnace efficiency by using coal
and other fuels (such as oil or gas) for heating
instead of coke, thereby minimizing air emissions.
• Recover the thermal energy in the gas from the
blast furnace before using it as a fuel. Increase
fuel efficiency and reduce emissions by improving
blast furnace charge distribution.
• Improve productivity by screening the charge
and using better taphole practices.
• Reduce dust emissions at furnaces by covering
iron runners when tapping the blast furnace
and by using nitrogen blankets during
tapping.
• Use pneumatic transport, enclosed conveyor
belts, or self-closing conveyor belts, as well as
wind barriers and other dust suppression measures,
to reduce the formation of fugitive dust.
• Use low- NOx burners to reduce NOx emissions
from burning fuel in ancillary operations.
• Recycle iron-rich materials such as iron ore
fines, pollution control dust, and scale in a sinter
plant.
• Recover energy from sinter coolers and exhaust
gases.
• Use dry SOx removal systems such as caron
absorption for sinter plants or lime spraying
in flue gases.
Steel Manufacturing
• Use dry dust collection and removal systems
to avoid the generation of wastewater. Recycle
collected dust.
• Use BOF gas as fuel.
• Use enclosures for BOF.
• Use a continuous process for casting steel to
reduce energy consumption.
Other
Use blast furnace slag in construction materials.
Slag containing free lime can be used in iron
making.
Target Pollution Loads
The recommended pollution prevention and control
measures can achieve the following target
levels.
Liquid Effluents
Over 90% of the wastewater generated can be
reused. Discharged wastewaters should in all
cases be less than 5 m3/t of steel manufactured
and preferably less than 1 m3/t.
Solid Wastes
Blast furnace slag should normally be generated
at a rate of less than 320 kg/t of iron, with a target
of 180 kg/t. The generation rate, however,
depends on the impurities in the feed materials.
Slag generation rates from the BOF should be
between 50 and 120 kg/t of steel manufactured,
but this will depend on the impurity content of
feed materials. Zinc recovery may be feasible for
collected dust.
Treatment Technologies
Air Emissions
Air emission control technologies for the removal
of particulate matter include scrubbers (or
semidry systems), baghouses, and electrostatic
precipitators (ESPs). The latter two technologies
can achieve 99.9% removal efficiencies for parIron
and Steel Manufacturing 329
ticulate matter and the associated toxic metals:
chromium (0.8 milligrams per normal cubic
meter, mg/Nm3), cadmium (0.08 mg/Nm3), lead
(0.02 mg/Nm3), and nickel (0.3 mg/Nm3).
Sulfur oxides are removed in desulfurization
plants, with a 90% or better removal efficiency.
However, the use of low-sulfur fuels and ores
may be more cost-effective.
The acceptable levels of nitrogen oxides can
be achieved by using low-NOx burners and other
combustion modifications.
For iron and steel manufacturing, the emissions
levels presented in Table 1 should be
achieved.
Wastewater Treatment
Wastewater treatment systems typically include
sedimentation to remove suspended solids, physical
or chemical treatment such as pH adjustment
to precipitate heavy metals, and filtration.
The target levels presented in Table 2 can be
achieved for steel-making processes.
Solid Waste Treatment
Solid wastes containing heavy metals may have
to be stabilized, using chemical agents, before
disposal.
Emissions Guidelines
Emissions levels for the design and operation of
each project must be established through the environmental
assessment (EA) process on the basis
of country legislation and the Pollution Prevention
and Abatement Handbook, as applied to
local conditions. The emissions levels selected
must be justified in the EA and acceptable to the
World Bank Group.
The guidelines given below present emissions
levels normally acceptable to the World
Bank Group in making decisions regarding
provision of World Bank Group assistance. Any
deviations from these levels must be described
in the World Bank Group project documentation.
The emissions levels given here can be
consistently achieved by well-designed, welloperated,
and well-maintained pollution control
systems.
The guidelines are expressed as concentrations
to facilitate monitoring. Dilution of air emissions
or effluents to achieve these guidelines is unacceptable.
All of the maximum levels should be achieved
for at least 95% of the time that the plant or unit
is operating, to be calculated as a proportion of
annual operating hours.
Air Emissions
For integrated iron and steel manufacturing
plants, the emissions levels presented in Table 3
should be achieved.
Liquid Effluents
The effluent levels presented in Table 4 should
be achieved.
Table 1. Load Targets per Unit of Production,
Iron and Steel Manufacturing
Parameter Maximum value
PM10 100 g/t of product (blast furnace,
basic oxygen furnace); 300 g/t from
sintering process
Sulfur oxides For sintering: 1,200 g/t; 500 mg/m3
Nitrogen oxides For pelletizing plants: 500 g/t; 250–
750 mg/Nm3; for sintering plants:
750 mg/Nm3
Fluoride 1.5 g/t; 5 mg/Nm3
Table 2. Target Load per Unit of Production,
Steel Manufacturing
(emissions per metric ton of product)
Blast Basic oxygen
Parameter furnace furnace
Wastewater 0.1 m3 0.5 m3
Zinc 0.6 g 3 g
Lead 0.15 g 0.75 g
Cadmium 0.08 g n.a.
n.a. Not applicable.
330 PROJECT GUIDELINES: INDUSTRY SECTOR GUIDELINES
Sludges
Sludges should be disposed of in a secure landfill
after stabilization of heavy metals to ensure
that heavy metal concentration in the leachates
do not exceed the levels presented for liquid
effluents.
Ambient Noise
Noise abatement measures should achieve either
the levels given below or a maximum increase in
background levels of 3 decibels (measured on the
A scale) [dB(A)]. Measurements are to be taken
at noise receptors located outside the project
property boundary.
Maximum allowable log
equivalent (hourly
measurements), in dB(A)
Day Night
Receptor (07:00–22:00) (22:00–07:00)
Residential,
institutional,
educational 55 45
Industrial,
commercial 70 70
Monitoring and Reporting
Air emissions should be monitored continuously
after the air pollution control device for particulate
matter (or alternatively an opacity level of
less than 10%) and annually for sulfur oxides, nitrogen
oxides (with regular monitoring of sulfur
in the ores), and fluoride. Wastewater discharges
should be monitored daily for the listed parameters,
except for metals, which should be monitored
at least on a quarterly basis. Frequent
sampling may be required during start-up and
upset conditions.
Monitoring data should be analyzed and reviewed
at regular intervals and compared with
the operating standards so that any necessary
corrective actions can be taken. Baseline data on
fugitive PM emissions should be collected and
used for comparison with future emissions estimates,
which should be performed every three
years based on samples collected. Records of
monitoring results should be kept in an acceptable
format. The results should be reported to the
responsible authorities and relevant parties, as
required.
Key Issues
The key production and control practices that will
lead to compliance with emissions guidelines are
summarized here.
• Prefer the direct steel manufacturing process
where technically and economically feasible.
• Use pelletized feed instead of sintered feed
where appropriate.
Table 3. Air Emissions from Iron and Steel
Manufacturing
(milligrams per normal cubic meter)
Parameter Maximum value
PM 50
Sulfur oxides 500 (sintering)
Nitrogen oxides 750
Fluorides 5
Table 4. Effluents from Iron and Steel
Manufacturing
(milligrams per liter, except pH and temperature)
Parameter Maximum value
pH 6–9
TSS 50
Oil and grease 10
COD 250
Phenol 0.5
Cadmium 0.1
Chromium (total) 0.5
Lead 0.2
Mercury 0.01
Zinc 2
Cyanide
Free 0.1
Total 1
Temperature increase £ 3oCa
Note: Effluent requirements are for direct discharge to surface
waters.
a. The effluent should result in a temperature increase of no
more than 3° C at the edge of the zone where initial mixing and
dilution take place. Where the zone is not defined, use 100
meters from the point of discharge.
Iron and Steel Manufacturing 331
• Replace a portion of the coke used in the blast
furnace by injecting pulverized coal or by using
natural gas or oil.
• Achieve high-energy efficiency by using blast
furnace and basic oxygen furnace off-gas as
fuels.
• Implement measures (such as encapsulation)
to reduce the formation of dust, including iron
oxide dust; where possible, recycle collected
dust to a sintering plant.
• Recirculate wastewaters. Use dry air pollution
control systems where feasible. Otherwise,
treat wastewaters.
• Use slag in construction materials to the extent
feasible.
Sources
British Steel Consultants. 1993. “Research Study, International
Steel Industry.” Prepared for the International
Finance Corporation, Washington, D.C.
The Netherlands. 1991. “Progress Report on the Study
of the Primary Iron and Steel Industry.” Third Meeting
of the Working Group on Industrial Sectors,
Stockholm, January 22–24.
Paris Commission. 1991. Secondary Iron and Steel Production:
An Overview of Technologies and Emission
Standards Used in the PARCOM Countries.
World Bank. 1996. “Pollution Prevention and Abatement:
Iron and Steel Manufacturing”. Draft Technical Background
Document. Environment Department, Washington,
D.C.