ECO SOLUTIONS SAVING RESOURCES, CREATING VALUE
A COMPREHENSIVE RANGE OF
FUTURE ORIENTED ENVIRONMENTAL
SOLUTIONS FOR IRONMAKING PLANTS

primetals.com

ECO SOLUTIONSSAVING RESOURCES, CREATING VALUE

As a result of increasingly stringent
environmental regulations and theneed to save resources and reduceenergy consumption, environmental
protection has become more
important than ever.
ECO Solutions from Primetals
Technologies stands for a wide rangeof services and advanced technologies
that minimize the environmental
impact of steel production, improveenergy efficiency and optimize byproduct management. Primetals
Technologies offers expert consulting
services, advanced processes andholistic solutions along the entire ironand steel production chain that ensure
strict adherence to the emission
regulations and support producers toachieve substantial cost savings. The
objective is always twofold: to saveresources and to create value.

GAS
CLEANING

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ENERGYEFFICIENCYECO SOLUTIONS
Saving resources• Optimized use of raw materials• Reduced energy consumption• Significant reduction in particulate
and gaseous emissions• Efficient by-product treatment andrecycling
Creating value• Improved plant performance• Lower conversion costs• Reduced environmental taxes anddisposal costs• Increased energy recovery• Substantially improved working
conditions and safety

BY-PRODUCTRECYCLING

ECOCONSULTING

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ENVIRONMENTALLY ORIENTED PRODUCTION
AND LOWER ENERGY CONSUMPTION
For every metric ton of steel produced, 50 to 100 kilogramsof sludge and scale accumulate and approximately 20,000
MJ of energy are consumed. There is no question thatmodern dedusting systems in combination with energyrecovery technologies and by-product recycling are crucial.
However, the outlay for such technology should be nohigher than absolutely necessary. The most important goals
are high reliability, strict compliance with defined thresholdvalues, and minimum energy consumption and maximum
by-product recycling.

YOU EXPECT

Primetals Technologies offers the entire spectrum of gas
cleaning and energy efficiency technologies as well as
by-product treatment plants from a single source, always
in close collaboration with your company’s iron and steel
production specialists. This is our approach for creating
perfectly coordinated and economically viable solutions.

• A reliable partner with innovative, tailor-made solutions• Cost-efficient production and maximized productivity• Low consumption levels for energy and utilities• Maximum energy recovery

ECO SOLUTIONSFOR IRONMAKING• Short delivery times and consistently high availability• Solid production quality and expert solutions• Designs that meet future environmental and market
requirements at the lowest investment

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ADVANTAGES OF PRIMETALS TECHNOLOGIES ECOSOLUTIONS

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Gas cleaning

Energy recovery

By-product recycling• Full compliance with agreed-upon limit values

4• Tailored ECO plants using comprehensive expertise• Future emission requirements already considered in theplant layout and design• More than 40 years of experience and profoundknowledge in environmental technologies

56Electrics and automation

Lifecycle services

Selected references

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MEROS®
MAXIMIZED EMISSION REDUCTION OF SINTERING
AND PELLETIZINGMEROS® plant at voestalpine in Linz, Austria

Developed by Primetals Technologies, MEROS® –Maximized Emission Reduction of Sintering – is a wastewater-free process for removing pollutant concentrations
such as dust and harmful metallic and organic components
from the sinter offgas. Through a series of treatment
steps, MEROS® achieves levels previously unattained withconventional gas-treatment techniques. The world’s first
MEROS industrial plant was installed at the sinter plant ofvoestalpine Stahl in Linz, Austria, and it has been running
reliably since 2007.
The MEROS® technology can be also applied for gas
cleaning in pelletizing plants. In the first step, special
C-based adsorbents and desulfurization agents (hydrated
lime or sodium bicarbonate) are injected into the sinteroffgas stream in the countercurrent direction to bind heavy
metals and organic compounds.

In the second step, the gas stream passes to a conditioning
reactor where the gas is moisturized and cooled to atemperature of about 90°C by means of an injected
fine mist using dual-flow, i.e., water and air, nozzles. This
accelerates the chemical reactions required for binding andremoving SO2 and other acidic gas components. In the third
step, the offgas stream that exits the conditioning reactor
passes through a bag filter equipped with special highperformance fabrics that remove the dust with the trapped
pollutants. In order to enhance gas-cleaning efficiency
and significantly reduce additive costs, a portion of thisdust is recycled to the offgas stream after the conditioning
reactor. This also accelerates the formation of a filter cakeon the surface of the bag filter, which enhances the removalof fine dust in the offgas stream. The dust removed fromthe system is conveyed to intermediate storage silos for
subsequent disposal or for use in other applications.

* (Hg, Pb...)

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DeSOx

Removal of
Heavy Metals*

Removal of
Organic
Compounds**

ECO SOLUTIONS –SAVING RESOURCES, CREATING VALUE
Saving resources• Up to 99% emission reduction• Dust emission less than 5 mg/Nm3• SO2 emission reduction up to 99% (depending on local
regulations)• Dioxin/furan emission reduction up to 0.1 ng TEQ/Nm3• Up to 10% (up to 200 kW/h) less energy consumption
compared with other technologies
Creating value

DeNOx

MAIN BENEFITS• Highest removal efficiency for heavy metals, acid gases,
dioxin and other VOCs thanks to the countercurrent flow
injection of additives• Lowest rate of dust recirculation resulting in fewer filter
pulse-cleaning cycles and minimal need of compressed
air for filter cleaning resulting in significantly extended
lifetime of bags
• Minimized mechanical stress on filter bags by using lowpressure pulse cleaning• Dry dust recirculation prevents any dust buildup in thesystem• Outstanding availability and veliability• Controlled constant process temperature ensures stable
desulfurization rates or sodium bicarbonate)• Proven lifetime of filter bags of eight years throughminimized mechanical stress on filter bags by using lowpressure pulse cleaning• Extension with a DeNOx system; changed to alternative
flexible, modular system• Treatment of MEROS® by-product possible, regenerationof soda/lime

MEROS = 5 IN 1 WASTE GAS CLEANING

Dedusting(fine dust)

Gas-conditioning tower

Pulse-jet filter

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SUCESSFULLYINSTALLED
MEROS®
PLANTS** (PCDD/F, VOC, ...)

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SCR DeNOX PLANTS FOR SINTER GAS CLEANINGPROVEN SOLUTIONS WORLDWIDE BASED ON
MORE THAN 1000 REFERENCESSCR REACTOR

Space provision for
additional catalyst
layer

Ammonia (NH3)
injection

Catalyst layer
Coke oven gas/
Natural gas
Combustion air

DUCT
BURNER
Soot blower

Steam

HEAT
EXCHANGER
Waste gas

3D Modell of SCR DeNOx plant for sinter waste gas cleaning

Primetals Technologies offers highly efficient selective
catalytic reduction (SCR) solutions for maximum reductionof nitrogen oxides emissions.
Harmful components in the sinter waste gas, such as dust,
SO2, heavy metals and organic compounds, are efficiently
removed in state-of-the-art sinter waste gas cleaning
plants. NOx emissions, however, have now become a key
focus of environmental legislation. It is expected thatemission limit values for nitrogen oxides will drop to very
low levels within the next few years.
NOx removal technology is already well established in otherindustrial sectors such as in the power generation industry.
This technology is increasingly being adopted in the ironand steel industry – mainly for sinter waste gas cleaning
and coke oven applications. The most efficient and reliable
solution for NOx reductions employs a selective catalytic
reaction (SCR). It has been successfully applied in power
plants since decades. With a few important modifications,
SCR technology has recently also been applied for sinterwaste gas cleaning.
Together with our partners from Mitsubishi Hitachi Power
Systems (MHPS), Primetals Technologies has developed
special solutions for both new and existing sinter plant
gas cleaning systems. In many cases the SCR DeNOx canbe an add-on module to existing dedusting and/or DeSOx
systems. One particularly interesting solution is the modular
SCR DeNOx add-on to MEROS sinter waste gas cleaning
technology.
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Cleaned gas

Process flow for NOx emission reduction

The SCR DeNOx process is based on the reaction of NOx
with ammonia (NH3). Nitrogen oxides (NOx) are reduced tonitrogen (N2) and water (H2O) according to the following
basic reaction:

ECO SOLUTIONS –SAVING RESOURCES, CREATING VALUE• NOx reduction up to 90%• Flexible design solutions for different applications (cokeoven, sinter- and pelletizing plants)

NO2 + NO + 2 NH3• Low ammonia consumption due to optimized gas flow
distribution by applying advanced CFD modeling• Lowest ammonia slip concentrations

2 N2 + 3 H2OThis reaction requires a certain temperature level and, mostimportantly, a suitable catalyst.
SPECIAL ADAPTATION OF THE SCR PROCESS FOR
SINTER WASTE GAS CLEANING

MAIN BENEFITS• Well proven in industrial applications

Saving resources• Reduced consumption of heating gas due to optimized
heat exchanger design ensuring a minimum temperaturedelta for pre-heating• Retrofit solution available for existing plants

Creating value

Due to the low temperature level of the incoming sinterwaste gas, the gas needs to be heated up to the optimum
reaction temperature of approximately 280°C. This is donein two steps.

• No by-product is generated

As a first step, the gas passes through a heat exchanger
where the heat from the outgoing treated gas is transferredto the incoming gas. The final temperature adjustment
is done by a duct burner system. Ammonia is injected
through an ammonia injection grid (AIG), which ensures auniform distribution of the ammonia across the duct before
the catalyst area. The gas then passes through the different
catalyst element layers. Both plate-type and honeycombtype catalyst elements are used.

• Proven high DeNOx-removal efficiency• Optimized catalyst material depending on specificapplication and waste gas composition for extended
lifetime

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DeNOx SYSTEMSSUCCESSFULLYINSTALLED IN
SINTER PLANTS>1,030DeNOx UNITSINSTALLED IN
POWER GENERATIONPLANTS**by our partner Mitsubishi Hitachi Power
Systems (MHPS)

9SELECTIVE WASTE GAS RECIRCULATION (SWGR)
ENERGY EFFICIENCY FOR SINTERROOM AND SECONDARY DEDUSTING FOR
SINTER AND PELLETIZING PLANTS

Selective waste-gas recirculation system (SWGR)

Dedusting systems for sinter plant

Waste-gas recirculation hood

In order to save capex and opex in MEROS® plants,
Primetals Technologies recommends installing a selective
waste-gas recirculation system wherever technicallypossible.

ECO SOLUTIONS –SAVING RESOURCES, CREATING VALUESELECTIVE WASTE-GAS RECIRCULATION SYSTEM• Reduction of CO2 emissions by up to 10%

Primetals Technologies has developed and implemented
the selective waste-gas recirculation (SWGR) system toreduce environmental emissions from sinter production.
With the SWGR system, offgas from selected zones of thesinter machine is mixed with hot cooler off-air and thenrecirculated to the sinter strand.

• Lower emissions of SOx, NOx, PCDD/PCDF and heavy
metals

The result is a significant reduction of the specific offgas
volume to the end-of-pipe gas cleaning by up to 50%.

Creating value

The SWGR system enables emission reductions in sinterproduction to previously unattained levels. Specificinvestment and operating costs for gas-cleaning facilities
can therefore be kept at acceptable low levels.
The SWGR system from Primetals Technologies can beinstalled in existing or greenfield plants.

Saving resources• Reduction of waste gas volume by up to 50%• Specific solid-fuel consumption decrease by up to 10% in
the sinter gas due to utilization of the contained CO andelevated recirculation gas temperature• Significant reduced investment and operation costs for
MEROS® plant

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SUCESSFULLYINSTALLED
PLANTS

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Aside from primary offgas treatment, it is also essential tohave ambient conditions in a sinter plant that ensure a safe
working environment. This is where reliable room dedusting
systems from Primetals Technologies come to play.
The main task of a room dedusting system is to efficiently
capture dust emissions that occur during the handling andprocessing of the sinter raw materials and hot sinter (e.g.,conveying, mixing, discharge, sieving). The proper designand location of hoods is essential to achieve the highest
dust collection possible and ensure proper working as well
as clean ambient conditions in and around the sinter plant.
CFD calculations help to design optimized dust capture
and flow distribution in the hoods. A further advantage isminimized pressure losses in the system, which results in
reduced power requirements for fans.
Primetals Technologies offers complete integrated solutions
that combine primary offgas treatment (MEROS®, selective
waste gas recirculation), room dedusting and the primary
sintering process.
Primetals Technologies’ pulse-jet filter removes dust fromthe raw gas stream, and assures highly efficient dedustingand increased lifetime for filter bags.

Secondary desusting system at one of thesinter plants of Ilva S.p.A. in Taranto, Italy

ECO SOLUTIONS –SAVING RESOURCES, CREATING VALUE
Saving resources• 15% savings in fan power requirements as a result of
optimized flow distribution and damper control• Total emission reduction up to <5 mg/Nm³ particulatematter• Clean working environment results in reduced
maintenance costs and improved working conditions forworkers
Creating value• Complete recycling of by-products via the sinter plant ispossible• Plant availability of >99%

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SUCESSFULLYINSTALLED
DEDUSTING
PLANTS

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ENERGY RECOVERY FOR SINTER PLANTS
TRANSFORM SINTER WASTE ENERGY INTOPROFIT

Waste gas
25%

Optional

Ignition fuel6%

Sinter cake
45%
SINTERSTRAND

Coke breeze
94%

A sinter cooler waste-heat recovery system with boiler exhaust air recirculation to the sintercooler

RECOVERY OF THERMAL ENERGY FROM THE SINTER
COOLER
The sensible heat of the sinter that is discharged from thesinter machine to the sinter cooler amounts to almost halfof the total process thermal energy input. Conventionalsinter coolers waste this huge amount of sensible heatby transferring it to the cooling air and releasing it to theatmosphere.
Primetals Technologies has developed solutions for
efficient recovery of this sensible energy by utilization of
hot waste air from the sinter cooler for production of steam
in a waste heat boiler system and optional generation ofelectrical energy in a modular power block. Special off-air
recirculation concepts lead to increased plant efficiency
and additionally ensure compliance with local emission
standards.

Hot sinter at the sinter machine discharge

Optimum integration of the energy-recovery system inthe energy network of a steelworks is decisive to ensure
maximum economic feasibility.
A payback time of less than three years is realistic,
depending of course on the plant size and local energy
prices.

Waste gas
30%
STEAM
GENERATORSINTER
COOLER

Unfeasible heat30%

Unfeasible heat
15%

Electrical Power
5%

Steam
17%

Unfeasible heat
13%

POWER
BLOCK

Unfeasible heat
12%

Main energy flows of the sintering process with heat recovery at the sinter cooler for the production of steam and, optionally, power generation

MAIN BENEFITS• Integrated solution in combination with sinter process
by optimized sinter cooler design (sinter cooler charging
and sealing) and automation level 2 burn-through point
control

Beside the utilization of sinter cooler waste heat for the
production of steam, there are several other possible
options for waste heat utilization, such as:• Preheating of combustion air for the ignition furnace (IF)to reduce gaseous fuel demand• Tailor-made steam generation maximized by recirculationof hot air back to the sinter cooler• The addition of a portion of sinter cooler off-air to theselective waste gas recirculation (SWGR) system

Considering the local conditions, the following process
variants of a sinter cooler waste heat recovery system canbe designed and provided:• Increased plant efficiency and compliance with theindividual emission standards through the efficientutilization of boiler exhaust air• Pre-heating of raw mix and post heating of freshly ignited
sinter to reduce coke breeze consumption• Feed-in to the on-site steam network for various processapplications• Elimination of emissions from cooler waste gas stack

A state-of-the-art sinter plant today consists of a sintercooler waste heat recovery system in combination with
SWGR and combustion air preheating at the IF to efficiently
utilize the full potential of the waste heat available in asinter plant.

• Generation of additional electrical energy in an existing
power plant• On-site generation of electrical energy in an autonomous
power block at the sinter plant• Utilization of produced steam or hot water for district
heating• Supply of steam to external consumers

ECO SOLUTIONS –SAVING RESOURCES, CREATING VALUE
Saving resources• Reduction of dust emission up to 5 mg/Nm³• Reduction of CO2 emission• Coke consumption reduced by up to 3% by recirculationof hot air back to the sinter machine
Creating value• Reduced operating costs through the production of
steam (~50–80 kWh/t sinter) or the generation ofelectrical power (~15–25 kWh/t sinter)• Typical payback times of less than three years dependingon the plant size and local energy prices

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SUCESSFULLYINSTALLED
PLANTS• Plant availability of >99%

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MERIMMAXIMIZED EMISSION REDUCTION AND ENERGYRECOVERY IN IRONMAKINGMERIM plant layout

Pilot plant

Primetals Technologies has developed advanced dry top gas
cleaning technology for blast furnaces, Corex and Finex, withconsiderable benefits for the environment and customers
compared to the conventional wet top gas cleaning systemwith its restrictions and disadvantages.

MAIN BENEFITSThe new system for blast furnace top gas cleaning includes a
cyclone for coarse dust separation and a high- performance
fabric filter for fine dust removal. The cyclone produces apractically zinc-free fraction of dust, which can be reusedin the sinter plant, and a highly enriched zinc fraction in the
fabric filters. In order to solve the problem of temperaturefluctuations in the top gas, Primetals Technologies hasdeveloped a gas-conditioning concept that allows for safe
operation at low and high temperatures alike. Using thisgreen solution, energy consumption and waste destinedfor landfills can be reduced to currently unachieved levels.
The cleaned gas meets both current and future emission
regulations, and the CO2 footprint can be significantly
reduced.

• Advanced emission control possible due to additive
injection and dust recirculation (e.g., HCl, H2S, COS)

• Dust product fully dry, no further sludge and waste-water
treatment necessary• Efficient separation, concentration handling andreutilization of by-products

Temperature control unit with burden burner and burden spray

ECO SOLUTIONS –SAVING RESOURCES, CREATING VALUE

Creating value

Saving resources• Clean gas concentration of <3 mg/Nm³• Dust separated at the first cleaning stage cyclone can berecycled without restrictions• Accurate separation of zinc in the cyclone, maximizing
the reusable portion of dust, i.e., in the sinter plant• Minimized energy consumption of 6–12 kWh/t of hot
metal• 25% to 30% higher energy output from the top gas
pressure recovery turbine (TRT) due to higher processtemperatures and lower pressure losses- Through higher energy recovery, additional profit of€300,000 to €600,000 per million tons of hot metal
produced (compared to wet dedusting processes)• Lower operating and investment costs compared to wet
solutions (e.g., electricity, water treatment)• Minimum maintenance required• Lower space requirements (about 40% to 60% lower
compared to a complete wet-type installation)

25-30%HIGHER
ENERGYOUTPUT
FROM TRT14

MERIM plant for Midrex

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SUCESSFULLYINSTALLED
PLANTS

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WET DEDUSTING SYSTEM FOR BLAST FURNACESMEETING ENVIRONMENTAL STANDARDS WITHHIGHLY EFFICIENT GAS CLEANING
Emergency
trip valve

Furnace top
pressure control

Generator
TurbineMain by pass valve

Dustcatcher
or cycloneConescrubber

Clean gas
goggle valve

Sub by - pass valve

PRIMARY WET DEDUSTINGSECONDARY WET DEDUSTING

MAIN BENEFITS

Primetals Technologies offers designs for dust catchersand cyclones, or a combination of both systems. However,where there is a need to remove higher percentages ofdust and to reduce water treatment requirements, the dust
catcher can be replaced by a cyclone. This is the case forboth new plants and for modernizations.

Primetals Technologies offers multiple solutions with
options for combinations of the washing/gas saturation
stage and the furnace pressure control stage:• Full range of solutions for all gas cleaning requirements

For the cyclone, Primetals Technologies offers two
solutions:• Single-side entry• Triple entry, which can replace the top of existing cyclone
designs that adopts swirl vanes and are susceptible toblockage or wear
A cyclone optimizes the recycling of blast furnace dusts
carried over in the offgas system via higher efficiency
separation. Additional benefits can also be realized in zinccarryover control.

• Optimized dust separation efficiency• The conditioning tower cools and saturates gas, removinga large percentage of dust particles• Fulfillment of the strictest environmental emission
limitations• The gas scrubber cleans process gas, guaranteeing dust
content of less than 5 mg/Nm³ while controlling thefurnace pressure to within 1.5% of its set point• Proven solutions on the basis of decades of experience

Xianghan blast
furnace conditioning
tower and scrubber

Gas scrubbers from Primetals Technologies have been in
operation for over 30 years with multiple units utilizing
single or triple annular cone devices on furnaces of varying
productivity and size. The latest generation of triple-conedesigns calls for an external position, away from the main
vessel, to facilitate ease of maintenance. The result is
reduced vessel size and a demister bed that can be locatedinternally.
All solutions developed for new gas cleaning plants arealso ideally suited for retrofitting into existing facilities. In
addition, corrosion has become an increasing problem for
operators with the higher prevalence of tuyere injectants.
Primetals Technologies has developed a cost-effective
and robust corrosion protection system based on carefulmaterial selection and internal coatings.

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TOP GAS RECOVERY TURBINE (TRT)
TRANSFORM OFF-GAS INTO PROFITHIGHT PRESSUREWITHOUTTRTWASTEDPRESSURE
ENERGY
HOT BLASTLOW PRESSUREHIGHT PRESSURE

WITH
TRT

HOT BLAST

3–D plant layout

In an integrated iron- and steelmaking plant, the blast
furnace and its auxiliary plants offer an important lever
for improving overall energy efficiency. The blast furnace
process consumes upward of 75% of the total energy in an
integrated steel plant. While modifications of central design
parameters usually require major investments, attractive
upgrades and improvement packages can be found formany existing plants.
The TRT recovers the pressure energy of the top gas ofa blast furnace by controlled expansion to low clean-gas
pressure. Electrical energy from the waste pressure canbe gained without any additional energy input and CO2
generation.

LOW PRESSURE

Utilization of energy from gas expansion

MAIN BENEFITS• Latest state of the art turbine design for the highest
energy efficiency and compact plant layout

ECO SOLUTIONS –SAVING RESOURCES, CREATING VALUE
Saving resources• Decreased amount of purchased electrical energy andreduction of CO2 footprint, and even the possibility toexport energy to a local grid

• Generation of electrical energy from blast furnace top
gas (approximately 30 to 40 kWh of electrical energy per
ton of produced hot metal)• Leak-proof construction allows a safe operation• In combination with a dry gas cleaning plant, 20% to 30%
higher energy output of the turbine• Inclusion of quick-acting valves to cope with loadchanges• Implementation after wet or dry top gas cleaning
possible• Precise blast furnace top-pressure control, even in thecase of an unexpected TRT stoppage

Creating value• Additional revenue from blast furnace production of €1.5
- €2.0 million per ton of hot metal (basis: €50/MWh)• Reduction of the CO2 footprint• No impact on the blast furnace operation with the
installation of an appropriate bypass system

SAVING OF

30-40
kWh/t
HOT METAL
18~ 30 – 40 KWH/THM
ELECTRIC ENERGYHigh efficient turbine (© MAN)

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SUCESSFULLYINSTALLED
PLANTS

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CASTHOUSE AND STOCKHOUSE DEDUSTING
FOR BLAST FURNACESDRY SLAG GRANULATION WITH HEAT RECOVERYUTILIZATION OF BLAST FURNACE SLAG HEAT
ENERGY

Casthouse taphole extraction

3–D layout of pilot plant for dry slag granulation

Casthouse

For casthouse dedusting, the exhaust system collects dust
laden air from the widely distributed off-take points. This
dust-laden air is then conveyed to a central fabric bag filter
unit for dedusting. Off-take points include the hot metaland slag tapping areas as well as hot metal transfer sites.

ECO SOLUTIONS –SAVING RESOURCES, CREATING VALUE

An important factor in the waste-gas extraction anddedusting logistics is optimum dimensioning of theductwork and the damper system to compensate pressure
losses and thus reduce fan power requirements. To optimize
the arrangement of hoods and ducts, CFD calculations
are carried out to support the design calculations. Special
design measures must be foreseen in order to assure
low wear as well as easy and low-cost servicing of sucha widely branched system. Bag filters are preferred forthe heart of the dedusting because of their flexibility inhandling varying quantities and dust concentrations in
the raw gas. This state-of-the-art filtration technology isrequired to reach the lowest emission values of <5 mg/Nm³
in the clean gas.

• Total emission reduction of <5 mg/Nm³

Drawing on operation and process experience with blast
furnaces, Primetals Technologies offers complete integrated
solutions for the offgas treatment in the blast furnace area.

Saving resources• 15% savings in fan power requirements as a result of
optimized flow distribution

Creating value• Complete recycling of by-products via the sinter plant,
blast furnace or LD(BOF) is possible• Clean working environment results in reduced
maintenance costs and improved working conditions forworkers• Plant availability of >99%

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SUCESSFULLYINSTALLED
PLANTS

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Each year, approximately 400 million tons of blast furnace
slag are produced worldwide with a tapping temperatureof around 1,500°C. The slag is normally used as a substitutefor cement clinker. Currently, the slag is granulated in wetgranulation plants using large volumes of water. It has notbeen possible until now to utilize the remnant heat energy
of approximately 1.8 GJ per ton of slag.
In an R&D project now underway by a consortiumof companies comprised of Primetals Technologies,
voestalpine Stahl, the FEhS – Building Materials Instituteand the University of Leoben, a new dry-granulation
technology is being investigated to use air to cool molten
slag and recover the lost heat energy. The resultant
granulated slag fulfills the same criteria as wet-granulatedslag for use in the cement industry.
Phase 1 of the project, which has been completed, involved
setting up a technical plant at the University of Leoben in2012. This was followed by a series of dry slag granulation
campaigns using remelted blast furnace slag. The elevatedoffgas temperatures and the quality of the slag producthave proven that the process is suitable as an industrial
application. The decision was then made to escalate theproject from a pilot scale to a full-size industrial prototype
plant. This phase 2 is now underway and commissioningis scheduled by end of 2016. Thus, it is expected that therollout of this leap-frog technology can start in 2017.

ECO SOLUTIONS –SAVING RESOURCES, CREATING VALUE
Saving resources• Reduced sulphur emissions• Elimination of sulphur odor around the plant• Reduction of CO2 footprint• Low emissions in the closed slag-granulation processwith a uniform grain size
• No water is consumed
Creating value• The dry granulation process saves 132 kWh energy
˜
per ton of slag sand for product drying (assuming 10%
residual moisture)• A slag flow of 1 t/min. gives an output of approx. 29 t/hsuperheated steam• The dry slag granulate can be used in the cement
industry21

RECYCLING OF BY-PRODUCTSOXIDE BRIQUETTING

Briquetting

Briquetting plant

Reycling of ironmaking waste materials

Around the world, government regulations concerning
environmental care are becoming more stringent, also
in regard to regulations and restrictions for depositing
and storing dust and sludge generated in the iron- andsteelmaking process.

In many cases, these by-products may be used as feedmaterial input in sinter plants without further processing,or sold at low value in order to avoid the space-consuming
and sometimes costly option of depositing the materials inor outside the plant.

ECO SOLUTIONS –SAVING RESOURCES, CREATING VALUE

These by-products such as iron-containing dust, sludge,oxide fines and scales as well as, for example, lime dusts
become a valuable resource and recycling becomesa profitable activity within a plant. Up to 10% in massof the total steel output of by-product materials are
generated within an integrated steel plant with an ironcontent ranging from 50% to 65%. In DRI-based plants, alarge amount of oxide fines, DRI sludge and DRI fines are
generated, either as a result of the process itself or during
material and product handling.

However, in many DRI-based plants there is no sinter plant
available for recycling, and the most effective way tomake use of the materials is in the direct reduction plant
as a partial pellet or lump-ore substitute. Not surprisingly,
the reuse of these by-products in direct reduction plants
is currently not state-of-the-art. Therefore, Primetals
Technologies has performed comprehensive studies andtests on briquetting iron-containing by-products. To verify
the physical stability and chemical reducibility of thebriquetted material, extensive laboratory tests (e.g., static
reduction tests) as well as field tests – so-called basket
tests – have been performed and proved to be successful.

Saving resources• Reduction of raw material consumption and thus
operating costs due to recycling of by-products (lumpore, pellets)• Sinter, pellets or lump ore bring savings of up to 7%
Creating value• Minimization of landfill and transport costs• Short payback period

17
SUCESSFULLYINSTALLED
PLANTS

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GASFERM
GENERATION OF ADDED VALUE FOR STEEL MILLOFFGASES

3-D plant layout for a double train installation

100% process gas recovery and utilization

Recycling carbon emissions from steel mills provides animportant new source for fuel and chemical production
while simultaneously reducing a steel mill’s carbon
footprint. Offgases generated from iron and steel
production contain significant amounts of carbon
monoxide (CO), carbon dioxide (CO2) and sometimes
also hydrogen (H2). Governments around the world are
setting ambitious targets for reduction of stationary
carbon emissions from industrial installations such as thesteel industry, thereby adding significant costs to steel
production.

Microbial fermentation of carbon and hydrogen-richoffgases, such as coke oven gas, blast furnace top gas,
direct reduction gas and converter gas to produce ethanol
or other basic chemicals, substantially mitigates CO2
emissions while simultaneously reducing NOx, SOx andparticulate emissions. The fuels and chemical products
produced in this manner deliver superior economic returns.
Greenhouse gas emissions from ethanol are up to 80%
lower compared with conventional gasoline, and between
30% and 50% lower per MJ of energy recovered whencompared with combustion for electricity generation.

GasFerm is a new development in offgas recycling thatsimultaneously addresses the need to reduce the steel
industry’s carbon footprint while improving a steelmaker’s
economic competitiveness through promotion of thecircular economy.

This technology is developed by LanzaTech. Primetals
Technologies is partner for plant implementation for theiron and steel industry.

MAIN BENEFITS• Added value for carbon-rich co-generation gases• Fuels und chemicals can be stored and globally traded,
while electrical power cannot• Chemical co-production adds diversification to the steelbusiness• GasFerm is a closed-loop, zero-waste process

ECO SOLUTIONS –SAVING RESOURCES, CREATING VALUE
Saving resources• Minimum 30% reduction in carbon footprint vs. power
generation• Energy conversion efficiency is 60% compared withpower generation efficiency of 35% to 40%• No food-crop usage as in other ethanol processes
Creating value• Net profit of ethanol produced is up to two times higher
than electrical power generation• 11 liters of ethanol per ton of liquid steel produced• Project internal rate of return (IRR) in the range of 25% to30%• Production cost per liter of ethanol up to 25% lower thantypical process for bio-ethanol production

4,5l/Nm CO-Gas
ETHANOL• Produced biomass replaces coal in sinter or blast furnace(23 MJ/kg biomass)• 100% process gas recovery and utilization

3

24

25

ELECTRICAL AND AUTOMATION SOLUTIONSElectronic modules of the bag filter units

Acoustic Expert

Blast furnace control room

BAG FILTER CONTROLACOUSTIC EXPERTThe next generation of dedusting control is a flexible
control of the whole system, from the damper to the stack,considering different operating points and combining theknow-how of Primetals Technologies and the experience of
operational personal:

In industrial plants a broad range of different equipment
is used which has to be monitored and checked with higheffort and different sensor strategies to guarantee it’s
proper function during the entire lifetime. The new Acoustic
Expert system is based on measuring sound, an important
property emitted by almost every device or process.
With this acoustic diagnostic system, monitoring a plant
gets a new dimension. Independent from all other sensor
strategies now the automation systems get ears.

HIGHEST PRODUCTION QUALITY AND COST-OPTIMIZEDOPERATION – SINTER OPTIMIZATIONENSURING SAFE AND COST-EFFICIENT OPERATION –BF OPTIMIZATIONThis system enables major cost savings and process
improvements without compromising raw material
selection, sinter quality, energy efficiency, and productivity.
Optimized raw mix calculation allows the production ofsinter material of the highest quality, while at the same timeeffectively reducing fuel consumption. Furthermore, thesystem provides a complete history of process parameters
including recipe, chemical and physical raw material
properties, and process measurements for a comprehensive
analysis of the sinter process. The result is smooth sintering
operation around the clock, an increased equipment
lifetime and reduced production costs.

The BF Optimization system was developed to operate
the blast furnace in a standardized way at stable operating
conditions. This closed-loop expert system corrects evensmall deviations by automatically executing the required
counteractions. This leads to cost-efficient operation andenergy-efficient production of hot metal (HM).

Thanks to intelligent control system with electronic
modules the Bag Filter Control optimizes bag filter
operation, featuring significantly reduced cleaning air
consumption as well as the detection of defect cleaning
valves. A fast and reliable system with self-monitoring
functions controls the cleaning valves, therefore increasing
the life-time of valves and filter bags.
MAIN BENEFITS• Automatic control of the entire bag filter system• High efficiency of the bag filter cleaning process• Pre-tested technological package including HMI, softwareand hardware• Powerful electronics replace conventional relays• Short implementation and commissioning time in new orexisting bag filter• Energy savings due to reduced cleaning air consumption• Reduction of maintenance costs

26

Typical fields of application are monitoring of bag filter
plants, wear of gas tuyers, gas leakage detection in valve
stations and all other applications emitting a specificsound.
MAIN BENEFITS• Support for maintenance staff• Preventive maintenance through trend evolution• Easy integration in existing automation, thus no plantshutdown for setup is needed• Minimal hardware costs• Immediate feedback to control system• Reduction of unplanned plant shutdowns

MAIN BENEFITS• Monitoring of process measurements and indicesbecomes more efficient• Process control practices become more uniform by using
fully closed-loop operation on the basis of all provided
expert system rules• Higher productivity (increase by up to 5%)• Stabilization of product quality (decrease of standard
deviation by 5-10%)• Reduced fuel consumption (decrease by up to 3%)

Stable process conditions are indicated by reduced
standard deviation of quality parameters such as hot
metal temperature or silicon content and result in reduced
fuel consumption of the blast furnace. Core modules areproduct quality and energy efficiency rules, the proceduresfor shutdown and start-up, the 3D hearth monitoring
package and the burden distribution model. At the sametime, data management and analysis tools provide processengineers with a sound information basis for further
process optimization.
MAIN BENEFITS• Reduction of fuel consumption by 5 kg/t
• Increased productivity (up to 3%) HM• Reduced standard deviation of HM temperature and Si
content (by 10%)• Stabilization of operation by avoiding critical situations

27

PROCESS & TECHNOLOGY CONSULTING
INCREASE PLANT PERFORMANCE AND REDUCECONVERSION COSTS

Consulting trough out the whole metallurgical production chain.

PROCESS AND TECHNOLOGY CONSULTING
You can profit from our integrated process know-how
and global presence. Process and technology consulting
help increase plant performance and reduce conversion
costs to support quick and proper selection of feasible
improvement measures.
Primetals Technologies offers technology-consulting
services that help operators to achieve and maintain highstandards in production excellence.

On the basis of decades of experience in the engineering,
installation, start- up and commissioning of steelmaking
plants worldwide, our specialists are skilled in identifying
potential for plant performance improvement in thecourse of a performance check. Detailed and individual
concepts are proposed to optimize processes and adapt
technological equipment to deal with different qualities ofraw material. By implementing these measures, operators
can ensure permanent production excellence and stay inline with environmental goals and remain cost effective.

LIFE CYCLE SERVICES FOR YOUR PLANT

OPERATIONALSUPPORTPLANT
UPGRADES

MAINTENANCESERVICES

BENEFIT FROM OVER 50
YEARS OF EXPERIENCELOW INVESTMENTS
FOR STATE-OF-THE-ART
TECHNOLOGY

ON- AND OFFLINE
MAINTENANCE AND REPAIRSERVICES

Decades of experience worldwide
in design, manufacturing
and commissioning as wellas consulting services formetallurgical plants ensure clients
receive innovative modernizations
and mechatronic solutions fortheir processing chain.

With a wide-ranging international
network of customer support
experts and worldwide repair
and maintenance workshops,
Primetals Technologies is yourideal single-source partner for
maintenance services.

Comprehensive services formetallurgical plants, from the
supply of original manufacturer
components, spare and wear
parts to consulting, technicalassistance and training.

With a portfolio consisting of operational support, plant
upgrades and maintenance services, you can focus on yourcore business while Primetals Technologies assures yourplant’s optimum performance.
STEPS FOR QUICK AND PROPER SELECTION OF FEASIBLE IMPROVEMENT MEASURESFACT FINDING AND
BENCHMARKFIND• Quick benchmark based on the
installed base and main raw
materials• Analysis of existing facility• Debottlenecking and productmix
28

INVESTIGATION AND
EVALUATIONEVALUATE• Improvement potential• Feasibility of investment

DETAILED
IMPROVEMENTELABORATE• Detailed plant specific measuresand specifications

With fast, reliable and experienced service and support forthe metallurgical industry, Primetals Technologies strives tobe a long-term lifecycle partner dedicated to your success.
We offer a full range of services across the entire lifecycleof your plant, including consulting and technical assistancedirectly from a single provider. Our service portfolio
covers all aspects: spare parts service available at just theright time; advanced staff training and technical support;
component upgrades to ensure plants are technically up
to date; repair service of key components for a longer
lifecycle; and on- and offline maintenance. Our services
reduce costs, increase productivity, improve product quality
and ensure safety.

29

REFERENCE PLANTS HIGHLIGHTSMEROS PLANT

SINTER COOLER HEATRECOVERY – SINTER PLANT #3

ROOM DEDUSTINGMERIM – KARDEMIRTOP GAS RECOVERY TURBINEBRIQUETTING – ILVA TARANTO

Customervoestalpine Stahl Linz, Austria
Type of plant
MEROS plant in combination
with SWGR

Customer
Dragon Steel Corp., Taiwan
Type of plant
Sinter cooler heat recovery

Customer
ILVA SpA, Italy
Type of plant
Sinter room dedusting

Customer
Kardemir A.S., Turkey
Type of plant
MERIM plant for blast furnaceincl. top gas temperature control

Customer
Vulkan Energiewirtschaft
Oderbrücke GmbHType of plantTop-gas recovery turbine
installed at Arcelor Mittal
Eisenhüttenstadt

Customer
ILVA SpA, Italy
Type of plant
2-line cold-briquetting plant

OUR SOLUTIONOUR SOLUTIONOUR SOLUTIONOUR SOLUTIONOUR SOLUTIONOUR SOLUTION

A fully satisfactory,
environmentally compatible
solution for the treatment of theoffgas arising during the sintering
process has not existed until now.
In response to this challenge,
Primetals Technologies developed
the MEROS process. In a series ofsuccessive treatment steps thedust and harmful metallic andorganic components present in
the sinter offgas are removed
to levels previously unattainedwith conventional gas treatment
techniques.

Dragon Steel Corp. wasinterested in recovering waste
heat from the cooling processof the sintered material andutilizing it for different on-site
applications.

The secundary dedusting
systems are able to clean 1,5
mio m3/h each and reduce
dust emissions from the sinterplants to less than 10 mg/Nm3
by application of Pulse Jet Filter
technology. The new dedusting
system is featuring long-life
bag filters and will replace theexisting systems, which are
based on technically obsolete
electrostatic precipitators.

Primetals Technologies was
responsible for the whole plantengineering as well as the supplyof critical key components andsupervision services during
erection and commissioning.
The clean gas content is max.
5 mg/Nm3 and, due to the drygas cleaning technology, approx.
25% more electrical energy canbe recovered at the downstream
installed top gas recovery
turbine.
The plant went into operation on
January 14, 2015.

The top gas pressure recovery
turbine from a European source
provides highest efficiency,
availability, and enables thecustomer to recover the
maximum amount of electricalenergy.

For the recycling of dust andsludge generated during iron andsteelmaking processes the fines
need to be agglomerated to form astable product that can be recycled
in the primary processes. Primetals
has developed a process including
drying of reactive sludge, mixing
and briquetting that produces astable briquette using a minimum
amount of binder. The briquette
product is used in the blast furnace
for substitution of sinter and in theLD(BOF) converter to substitutecooling ore and scrap.

TECHNICAL DATATECHNICAL DATATECHNICAL DATATECHNICAL DATATECHNICAL DATATECHNICAL DATA

Gas Flow:
650,000 Nm³/h

Gas Flow:
500,000 Nm³/h

Off-gas Volume:2 x 1.500.000 m3/h

Blast Furnace Data:
Volume:		1650 m3
Production:
1.2 mt/yBlast Furnace Data:
Volume:		
300,000 Nm3/h
Pressure:
1.6 bar(g)Design capacity:
approx. 45 t/h(Design: 240,000 t/y)Clean gas dust content:< 5 mg/Nm³

Gas temperature:
335 ºC

Dust emission:
less than 10 mg/Nm3

Top gas data:
Volume:		
Pressure:

Turbine:Power: 		
6.99 MW
Speed: 		
3,000 rpm
Possibility for on- and offline
washing

Binder system:
molasses/hydrated lime

Synchronous generator:
Power:		
8.44 MVA
Speed: 		
3,000 rpm / 2 pole

LD(BOF): approx. 4 t/heatSO2 removal:
technically up to 98% SO2
possible
Dioxin clean gas content:< 0,1 ng/Nm³

Primetals Technologies supplied
an efficient waste-heat recovery
system that extracts the usable
portion of the available waste
heat from the circular cooler andsubsequently converts it into
process steam with a dedicatedsteam boiler.

Steam production:
31 t/hNoise pressure level:
max. 85 dB(A)Steam pressure:19.0 bar(g)Average lifetime of bags:
minimum 2 years

Steam temperature:		
274 ºC30

400,000 Nm3/h
2,5 bar(g)Briquettes used in BF & LD(BOF)
process (approx. 50%)

BF: approx. 1% of burden

31Primetals Technologies Austria GmbHA Group Company of Mitsubishi Heavy Industries

Turmstrasse 44
4031 Linz
Austriaprimetals.com
Brochure No.: T01-2-N194-L4-P-V4-EN
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in this document contains merely general descriptions or
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not binding upon the parties. Any obligation to provide and/or
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These estimates and assumptions have to be analyzed on acase-to-case basis and might change as a result of further
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