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Ferroalloy Process Engineering - Track Record
New furnace feed system for Tubatse Ferrochrome
Bateman Engineering has upgraded the furnace feed system at Billiton's Tubatse Ferrochrome plant in
Steelpoort, Mpumalanga, RSA. The previous feed system comprised a number of conveyors feeding
through the furnace roof directly into the furnace, while the new feed system consists of a conveyor
feeding raw material to a new storage bin at a rate of 150 t/h.The stored material is drawn from the bin by five vibrating feeders and fed into the furnace through seven
feed chutes with water-cooled tips. The entire chute system is air cooled.The challenge was to install the new system into the very limited space available in the existing building
and position the new bin above an existing opening in the concrete floor. The structure of the building
also had to be substantially strengthened to accommodate the additional load of the 120 t capacity
storage bin.This caused a height constraint and this, together with the position of the transferring conveyor,
resulted in the need for an unusually-steep troughed conveyor, angled at 26°. The position of the
feed chutes required a number of extremely long vibrating feeders up to 8 m in length.This lump-sum turnkey project valued at R8.5 million arose out of a successful engineering study,
conducted by Bateman Engineering, to investigate the possibility of replacing the furnace feed system
at the plant.A good relationship existed throughout the project between Bateman Engineering's project personnel
and the client, ensuring that progress proceeded according to schedule.BATEMAN rebuilds Transalloys No. 3 Furnace in 105 days
Highveld Steel and Vanadium Corporation commissioned its Transalloys Furnace No. 3 at Witbank,
South Africa in October 2005, following a successful BATEMAN mini-rebuild that took just 105 days.The lump sum turnkey (LSTK) contract awarded to BATEMAN to rebuild the furnace included the supply
of a new furnace foundation, shell and refractory lining, shell hearth-cooling system, operator tapping
platform and related tapping equipment, such as a rail-mounted clay gun and tap drill arrangement
and two control stations. A fume-extraction system was installed to manage fumes generated during the
tapping process, in compliance with Transalloys' overall commitment to environmental conservation.
In addition, the existing electrode-clamping device was replaced with the more advanced BATEMAN model.In the rebuild, the existing rotary furnace was replaced with a stationary, dual tap-hole furnace, and radial
cooling system. The latter is able to provide an average air flow of 15 m/s, thereby efficiently cooling the
furnace base. The entire tapping floor was rebuilt and two new tapping launders fitted.The BATEMAN electrode slipping / clamping device was conveniently adapted to operate within the envelope
of the replaced slipping device, with only minor structural modification to the support structures of the main
building. The device was also modified to accommodate selected components of the replaced slipping
device, saving on both time and cost. The adaptability of the clamping device has proved to be a key
element in the successful installation of the device.Installation was constrained by existing major building structural steelwork, as well as the lack of available
work space. However, despite the constraints and extremely tight schedule, Bateman still managed to
successfully complete the project within 105 days.US$50m contract for IFM's pelletising and sintering plant
BATEMAN has been awarded the lump-sum turnkey (LSTK) contract to design and build a 400,000 t/yr
pelletising and sintering plant using Outokumpu's chromite-ore pelletising and sintering technology for
part of the new US$250-million International Ferro Metals (IFM) ferrochrome plant.The plant is planned for the western limb of the Bushveld Complex near Brits in the North West Province,
RSA. The contract, worth US$50 million to Bateman, is for the up-rated requirement of 400,000 t/yr
sintered chromite pellets.IFM was founded by Australian entrepreneurs and has now been listed on the Alternative Investment
Market (AIM) of the London Stock Exchange, in alliance with Jiuquan Iron & Steel Group (Jisco) based
in the Gansu province of China's north-west.The goal is to have the plant built within 17 months. BATEMAN and Outokumpu will be jointly responsible
for the basic engineering and supply of equipment, with Outokumpu supplying the core pelletising and
sintering technology. This technology is well proven and improves chromium recoveries by at least
10 % and consumes up to 15 % less energy than conventional open or semi-closed furnaces when
using a mixture of lumpy ore and sintered pellets as feed.BATEMAN has already commenced the preliminary design phase for its portion of the project and will be
providing the balancing technology. The components for this portion of the plant will be sourced both in
South Africa and Europe, as will a large portion of the technology equipment to be supplied by Outokumpu.The Bateman-Outokumpu team has a strong track record in this industry, having supplied a similar plant
for SA Chrome and Alloys' ferrochrome facilities at Boshoek in the same area. This plant produces about
230,000 t/yr of saleable charge ferrochrome and comprises two 54 MVA closed submerged-arc furnaces
and a pelletising and sintering plant, processing 520,000 t/yr of material. The lower energy consumption
also reduces the ecological impact associated with fossil-fuel electrical energy generation.BATEMAN has a global capacity for this type of metallurgical project and one of the largest reference lists
in Southern Africa, with large installations supplied in the past few years to Assmang at Machadodorp and
Poschrome, Crometals at Samancor's Ferrometals site, Witbank, all located in Mpumalanga, Hernic
Ferrochrome near Brits and Samancor Metalloys in Meyerton, Gauteng.Definitive feasibility study for Shevchenko project
BATEMAN has been contracted by Oriel Resources plc for the definitive feasibility study (DFS) on a
ferronickel-process plant for the Shevchenko project in Kazakhstan.This follows the successful completion of the prefeasibility study (PFS) on the project for which
BATEMAN was contracted by the South African metallurgical research institute, Mintek, to provide the
engineering input due to its previous experience on similar DC-arc smelting studies.
BATEMAN's share of the approximately US$5,5M contract is some US$3,6M.With the PFS having established the potential viability of the project, the DFS will develop the project
further by quantifying the potential capital and operating costs and identify other aspects such as site
infrastructural requirements. The objective is to generate definitive documents for the financial
institutions to attract the necessary funding.The English version of the document is due for completion by the end of August 2005, after which
it will be translated and submitted for approval by the Kazakhstan authorities.Testwork is also being carried out on milling, preheating and smelting to further determine whether
the nickel can be extracted successfully in commercial quantities with the proposed DC furnace
technology. Polysius of Germany has been contracted to undertake the milling and preheating
testwork and to design the commercial scale plant. Mintek has been contracted to do a smelting
test on 450 t of ore and to supply the critical design parameters for the DC furnaces.In the processing tests carried out during the PFS by Mintek, a crude ferronickel product with in
excess of 20 % nickel was produced under optimal conditions. Recoveries were conservatively
estimated at 89 % and the optimal conditions were determined to be the addition of 4,5 % coal
and 9 % magnesite flux to the furnace feed. During the tests, 6 t of the Shevchenko nickel ore was
dried, calcined and smelted in Mintek's 200 kVA DC-arc furnace at a temperature of about 1 600°C
and at an average feed rate of 65 kg/h.BATEMAN joins forces with COMETVA SA to market the latest technology in electrode columns for AC furnaces
BATEMAN has signed a collaboration agreement with COMETVA SA, providing clients of both companies
the option of utilising the new hydraulic electrode-clamping device from BATEMAN, together with forged
copper electrode components, sold under the brand COFOR, from COMETVA SA. This agreement
therefore provides the industry with access, through a single source, to the latest technology and
improvements in electrode columns.In accordance with the agreement, BATEMAN and COMETVA SA / FAi Production will continue to
market their services independently but offer equipment available from both companies, where appropriate.COMETVA SA is the international sales office of the well-known French company FAi Production, which
specialises in the design and production of forged copper contact shoes and pressure rings. As the
world's leading producer of forged copper electrode components for more than 20 years, COMETVA
SA / FAi Production's range offers reduced furnace energy consumption due to the material quality
obtained by the unique multiple-forging process. In addition, enhanced electrical and thermal
conductivity, as well as cooling efficiency, make these components ideal for applications where
extreme-heat conditions prevail, while the greatly increased copper mass and customised design
have provided enhanced structural integrity.BATEMAN is a leader in the design and construction of AC furnaces for the pyrometallurgical industries,
and its well-proven AC smelting process know-how includes the BATEMAN electrode system. The
newly-developed electrode clamping device for this system can be installed on the full range of AC
installations (including closed and semi-closed submerged-arc furnaces). The device consists of three
clamping shoes joined together with pins, links and pendulum arms. The pendulum arm is designed to
clamp the electrode casing at a leverage ratio that requires less movement of the links, springs and all
other moving parts than with conventional devices. As a result the wear on all moving parts is reduced
to a minimum. This robust and trouble-free design means that very little lubrication is required after
installation and there is minimal maintenance and low operator involvement.When installed on the electrode column, the bottom clamping device, which has two force strings
equipped with springs, is used for normal electrode regulation. The opening of the clamp is driven
by a hydraulic cylinder, and preloading of the force string is easily set by means of a hydraulic bolt-
tensioning system. The top clamping device is normally open and is closed using a hydraulic cylinder.
The fail-safe, spring-clamping force is distributed equally over the contact area of the electrode casing,
minimising deformation of the casings. The tensioning forces are continuously monitored by means
of two load cells, one on each force string on the clamping device. This online readout provides the
furnace operator in the control room with a direct reading of the clamping force.BATEMAN's electrode system offers a number of benefits including long slips and back slips, made
possible by the use of long hydraulic cylinders. The normal operating stroke is 1 m and a maintenance
stroke of 1,5 m can be accommodated. In addition, the slipping sequence is much faster compared to
electromechanical drive units.Bateman electrode column for UMSL, India
BATEMAN has been awarded a contract to supply an electrode column to Utkal Manufacturing & Services
Ltd (UMSL) in India for their new 27 MVA submerged-arc, high-carbon ferrochrome furnace.UMSL, situated in the state of Orissa on the eastern coast of India, is part of the IMFA Group, which is
the largest producer in India of high-carbon ferrochrome, ferrosilicon and special magnesium alloys.The new electrode column is designed for both submerged- and open-arc furnaces and offers the
following benefits: long slips and back slips can be taken as a result of long hydraulic cylinders and
the slipping sequence is much faster compared to the previous electromechanical drive units.An important part of the system is BATEMAN's new electrode-clamping device. This simple and robust
device provides significant benefits, including no need for lubrication after installation and minimal
maintenance; low operator involvement; minimal wear on moving parts; and much faster slipping
rates for better process control, in comparison to the electromechanical units.The lump-sum turnkey contract from UMSL comprises the design, supply and supervision of the
erection and commissioning of a 1 270 mm BATEMAN electrode column, electrode holder and
bustube system.The IMFA Group is involved in a major expansion to its current 130 MVA installed furnace capacity,
which will increase, over three phases, its ferrochrome production by 140 000 t/yr. The expansion
involves establishing additional furnace capacity on land next to its existing industrial complex at
Choudwar, Orissa and has been initiated to take advantage of the resurgence in the ferrochrome
industry on the back of a strong demand, particularly in Asia.New furnace electrode-clamping device offers improved process control
BATEMAN's new electrode-clamping device for furnace installations offers the ferroalloy industry
significant benefits, including no lubrication required after installation and minimal maintenance;
low operator involvement; minimal wear on moving parts and much faster slipping rates for better
process control, compared to the previous electro-mechanical drive units. An order for the new
device has already been received from an international client.The electrode-clamping device can be installed on the full range of AC-and DC-furnace installations
(including closed, semi-closed and open, submerged-arc furnaces) and can be designed for any
size electrode. They are easy to assemble and disassemble and can be retrofitted to existing installations.The device is compact with a lightweight construction for ease of handling, and is easy to access for
adjustment purposes. Its robust and trouble-free design features a fail-safe, spring clamping force that
is distributed equally over the contact area of the electrode casing thus reducing wear. The opening of
the unit is driven by a small hydraulic cylinder that is simple to maintain, and preloading of the force
string is easily set by means of a hydraulic bolt-tensioning system. The tensioning forces are continuously
monitored by means of two load cells, one on each force string. This online clamping force readout allows
the furnace operator to have a direct, online load reading in the control room. An alarm is raised in the
event of a deviation from the norm and further slipping of the electrode will be stopped or prevented
if the clamping forces fall below the limits.The device, which was designed and developed in-house by BATEMAN engineers, has undergone a
test campaign of 300 000 cycles, representing an in situ operation of more than 20 years
(based on 35 slips per 24 h period).BATEMAN's AC- and DC-smelting know-how is well-proven, having been installed on some of the latest
and largest ferroalloy plants worldwide. At the core of this expertise is a focus on innovative equipment
and the enhancement of key technologies to sustain even the most severe operating conditions and to
ensure that production costs are at the lower end of the world's industry standards.BATEMAN designs and supplies complete AC- and DC-furnace plants to process ferroalloys and
platinum-group metals. Besides greenfield operations, BATEMAN will also increase the output of
existing smelters, improve their efficiency and reduce the cost per ton of product produced.DC-smelting study on nickel ore from Shevchenko, Kazakhstan
BATEMAN was contracted by Mintek to provide the engineering input to a prefeasibility study for Oriel
Resources plc on a ferronickel-process plant for the Shevchenko project in Kazakhstan.
The study was completed successfully.BATEMAN handled the engineering design and costing of the process plant and became involved
in the project because of its previous experience on similar DC-arc smelting studies.The processing tests, conducted by Mintek's Pyrometallurgical Division, were positive. Mintek dried,
calcined and smelted 6 t of the Shevchenko nickel ore in its 200 kVA DC-arc furnace at a temperature
of about 1 600°C at an average feed rate of 65 kg/h. Optimal conditions were achieved when adding
4,5 % coal and 9 % magnesite flux to the furnace feed and yielded a crude ferronickel product with in
excess of 20% nickel with recoveries conservatively estimated at 89 %.As a result, Oriel Resources, which is listed on the London Stock Exchange, is considering a definitive
feasibility study on the project.
Ferrometals' Furnace 4 upgraded to 60 MVA
BATEMAN has completed an upgrade of Ferrometals' Furnace 4 (F4) in Witbank, RSA, for Newsam
Pty Ltd (a joint venture between Samancor and Poschrome) to increase the furnace's production
capacity from 100 000 t/yr of ferrochrome to 125 000 t/yr.The project site work was undertaken during a shutdown of the plant from 30 June to 4 September 2003
and was finished four days ahead of schedule.The upgrade and rebuild of F4 follows a similar upgrade of Furnace 5 at the same site during 2002 and
involved the existing 48 MVA furnace being upgraded to a 60 MVA closed submerged arc furnace. The
nominal operating power is expected to be about 48-50 MW, with capability to operate at a maximum
of 52-55 MW.The shutdown started with the demolition of the furnace (roof, shell and feed chutes) and removal of the
furnace burden. Civil work on the furnace supports started when the area had been cleared and upgrade
work commenced on the raw materials handling system at the same time.The two closed furnaces at Ferrometals' site in Witbank, F4 and F5, share a common feed system.
The raw materials are fed to the furnaces' respective proportioning bunkers via a fines screen and
flopper gate system onto a series of conveyors. The raw material handling system was upgraded
by rearranging existing feeders and installing new vibrating feeders to increase feed capacity by 25 %.After proportioning, an incline conveyor raises the material to the Outokumpu pre-heater. The feed
mixture is heated by furnace off-gas, mainly carbon monoxide (CO), before being choke fed into the
furnace via nine refractory lined chutes, which were also replaced during the shutdown.The feed material is then smelted in the furnace, the main reaction being the reduction of chromite,
during which CO is generated. The furnace off-gas is removed by extractor fans and passes through
wet scrubbers for cleaning and cooling. The pre-heater consumes the CO gas for pre-heating and the
remainder of the gas is available in the network or it can be flared. In order to control the furnace pressure,
two new CO fans were installed to cope with the increased volumes of CO being generated in the furnace.
Knock-out separators were installed after the furnace venturi scrubbers to remove remaining solid particles
and moisture in the gas stream.The furnace was replaced by a BATEMAN-designed furnace and roof. The shell diameter was increased
from 13 m to 13,7 m, incorporating a UCAR / BATEMAN Chill KoteTM lining. This lining consists of
conductive refractory on the cold face and insulating refractory on the hot face in the metal and slag zone.
This effectively increased the crucible diameter by more than 2 m.Three 21 MVA transformers replaced the three 16 MVA transformers. The increased furnace power input
also necessitated an increase of the electrode pitch circle diameter (PCD).The Chill KoteTM / freeze layer on the hot face of the refractory relies on adequate and continuous cooling
to ensure that the hot face temperature stays below the solidus temperature of the metal and slag. A
furnace refractory lining monitoring system was developed by Bateman and installed to monitor refractory
wear and Chill KoteTM / freeze thickness. Shell film cooling water is collected in a tank from where it is
redistributed to the header and tundish of the furnace shell. A side-stream filter unit removes solids
in the water.Roof cooling is accomplished by a closed-circuit cooling-water system and dedicated cooling towers.
A single, main taphole was provided together with an emergency taphole above the main taphole at an
angle from the centre line, to be used for upset conditions.
Commissioning was a continuous process, signing off systems as they were completed by the
construction teams. Start-up was accomplished with no significant mechanical, electrical or
instrumentation malfunctions.SA Ferrochrome exceeds criteria in performance tests
The newly installed furnaces and sintering plant at SA Ferrochrome exceeded performance and
design criteria in performance tests recently completed by BATEMAN. In addition, following
commissioning, monthly targets were increased constantly.This new greenfields installation for SA Ferrochrome (Pty) Ltd was commissioned by BATEMAN as a
lump-sum turnkey project at Boshoek, some 20 km north of Rustenburg, North West Province, RSA,
towards the end of 2002. The plant has a design capacity of 235 000 t/yr of saleable charge chrome
from a blended feed of lumpy chromite and chrome concentrate. It consists of two 54 MVA closed
submerged-arc furnaces and a pelletising and sintering plant to process 520 000 t/yr of chromite pellets.The tests on the furnaces were conducted together with Outokumpu during July 2003 and criteria in
terms of both chrome recovery and power consumption were exceeded during the seven-day trial.
Chromium recoveries in excess of 84 % were achieved on both furnaces and the energy consumption
was below 3 150 kW h/t. SA Ferrochrome is currently achieving a constant throughput on both furnaces
on an average load of 46 MW each.The pelletising and sintering plant from Outokumpu also reached full production in January 2003, only
four months after commissioning, and was performance tested over a 72-hour period in April 2003.
The plant reached a throughput of 85 t/h wet feed to the sinter machine, thus exceeding the design
capacity of 520 000 t/yr. Performance criteria in terms of both plant throughput and quality of pellets
were achieved during the test period.Two ore types are processed in the plant, a high-grade LG6 and a lower-grade UG2 ore. The LG6 ore
is brought by road from SA Chrome’s Horizon mine, located some 40 km to the north west of the smelter.
The UG2 concentrate, a discard product from platinum mining, is purchased in terms of a long-term
agreement from Impala Platinum’s nearby UG2 concentrator.
A blend of about 40 % LG6 ore and 60 % UG2 concentrate is supplied to the furnaces to ensure a
chrome-alloy product with a minimum grade of about 51 %. This blend is milled with coke, filtered
to remove excess water, mixed with bentonite and pelletised. Green pellets between 10 and 15 mm
pass through drying, preheating, sintering and cooling zones in the sintering furnace to ensure that
they contain iron in the ferric form which is more easily reduced, with a porous structure and high-
temperature strength to enhance the rate and uniformity of reduction in the furnaces.Stockpiled sintered pellets are mixed with other raw materials and conveyed to the preheater above
the furnace, where they are heated to 600 °C by burning scrubbed gases from the furnace. The use
of preheated pellets as feed to the furnaces reduces power consumption as well as reducing electrode
consumption and maintenance, while increasing the furnace capacity and ensuring its smooth operation.BATEMAN also prepared the environmental impact study for the project and was instrumental in
preparing the bankable feasibility study.BATEMAN Engineering NV upgrades ferrochrome furnace for Crometals
BATEMAN has completed the lump-sum turnkey upgrade of Furnace No. 5 at Samancor’s site in
Witbank, RSA, and has increased its ferrochrome output by 25 % to 125 000 t/yr of metal.
Simultaneously, the cost per ton of ferrochrome produced was reduced by improving the
efficiency of the furnace. Part of the BHP Billiton Group, Samancor is one of the largest
ferrochrome producers in the world.The client was Crometals, a joint partnership between Samancor and NSA Metals (Nisshin Steel and
Nissho Iwai of Japan). The contract was secured in January 2002 and was completed on schedule on
25 November 2002 during a nine-week shutdown commencing on 23 September.The enhanced furnace performance was achieved essentially by providing a new, but proven, design
for the furnace and technology for its roof and lining.The refractory lining, shell, grillage, roof and feed chutes of the existing furnace were demolished and
a new furnace shell installed, featuring the BATEMAN/UCAR freeze-type refractory lining. The shell also
features a new cooling system with a furnace-lining monitoring system. The lining concept is a unique
BATEMAN development installed in furnaces now operating successfully at Hernic Ferrochrome,
SA Chrome and Assmang Chrome in RSA and Temco in Australia.The furnace preheater at the plant was reinstated so the raw material could be heated prior to feeding
into the furnace. This feature results in a much more efficient and economical smelting process.A new roof was also fitted to the furnace. This is a BATEMAN design, used successfully at SA Chrome,
Assmang Chrome and Hernic Ferrochrome, and allows efficient smelting because of the appropriate
positioning of the electrodes in the furnace. It also prevents the ingress of air into the furnace and the
release of toxic gases.The existing raw-materials-handling system was refurbished to increase the feed to the furnace by
25 % by widening the belts and structures and changing the drives, pulleys, idlers and feeders.The carbon-monoxide booster fans were up-rated, as were the effluent-treatment plant and
granulation-cooling system. A new clay gun and taphole drill was installed.The power supply to the furnace was increased from 48 to 60 MVA by upgrading the furnace
transformers and, simultaneously, the 33 kV supply in the high-tension yard was modified to
suit the new furnace transformers. New motor-control centres were also installed.The contract was awarded to BATEMAN following an open-book negotiation. The successful
completion resulted in a follow-up contract for an identical upgrade of Furnace No. 4 at the site,
which will be done during July and August 2003.SA Chrome’s Ferrochrome Smelter
The new greenfields smelter, pelletising and sintering plant for SA Chrome and Alloys Limited has
been commissioned as a lump-sum turnkey project by BATEMAN at Boshoek, some 20 km north of
Rustenburg, North West Province, RSA. The first metal was tapped only 15 months from the
receipt of the order.The plant has a design capacity of 235 000 t/yr of saleable charge ferrochrome from a blended feed
of lumpy chromite and chrome concentrate. It consists of two 54 MVA closed submerged-arc furnaces
and a pelletising and sintering plant to process 520 000 t/yr of material. The closed-furnace technology,
a new but proven BATEMAN design featuring Outokumpu pre-heating, is environmentally friendly.
Smelting of chromite during the production of ferrochrome can lead to the production of chromium VI,
which is highly toxic. However, the closed furnaces preclude the ingress of air (oxygen) into the hot
interiors, so that chromium VI cannot be formed.Outokumpu’s sintered-pellet smelting process is proven technology. This process route improves
chromium recoveries by at least 15 % and consumes 25 % less energy than conventional open or
semi-closed furnaces, ensuring that SA Chrome will be the lowest-cost chromium producer. The
lower energy consumption also reduces the ecological impact associated with fossil-fuel electrical
energy generation.Two ore types are processed in the plant, viz. a high-grade LG6 and a lower-grade UG2 ore. The LG6
ore is brought by road from SA Chrome’s Horizon mine, located some 40 km to the northwest of the
smelter. The UG2 concentrate, a discard product from platinum mining, is purchased in terms of a
20-year agreement from Impala Platinum’s nearby UG2 concentrator.A blend of about 40 % LG6 ore and 60 % UG2 concentrate is supplied to the furnaces to ensure a
chrome-alloy product with a minimum grade of about 51 %. This blend is milled with coke, filtered
to remove excess water, mixed with bentonite and pelletised. Green pellets between 10 and 15 mm
pass through drying, preheating, sintering and cooling zones in the sintering furnace to ensure that
they contain iron in the ferric form which is more easily reduced, with a porous structure and high-
temperature strength to enhance the rate and uniformity of reduction in the furnaces.Stockpiled sintered pellets are mixed with other raw materials and conveyed to the preheater above
the furnace, where they are heated to 600 °C by burning scrubbed gases from the furnace. The
use of preheated pellets as feed to the furnaces reduces power consumption as well as reducing
electrode consumption and maintenance, while increasing the furnace capacity and ensuring its
smooth operation.BATEMAN also prepared the environmental impact study for the project, was instrumental in
preparing the bankable feasibility study and facilitated the off-take agreement for the ferrochrome
product. These ensured that SA Chrome was able to raise the necessary equity and loan finance
for the project and arrange a five-year off-take agreement with Thyssen Krupp in Germany for this
ferrochrome output.
Ferroalloy processing
BATEMAN, through its subsidiary Bateman Titaco (Pty) Ltd, is a leader in the design and construction
of processing facilities for the production of ferroalloys. With the largest reference list for this type of
project in Southern Africa, its ferroalloy processing know-how includes smelting, upgrading of ore,
pollution control, raw-materials handling, metal casting, product handling, smelter utilities, sludge
treatment, handling and remelting of fines and extracting metal from slag.BATEMAN’s well proven alternating current (AC) smelting process has been installed on some of the
latest and largest ferroalloy plants worldwide with the lowest production costs, e.g. Hernic, Assmang
Chrome and SA Chrome.The electrode system for closed submerged-arc furnaces is a core BATEMAN technology in these new
installations. This specialised range of equipment for AC smelting offered by BATEMAN now includes
the Söderberg electrode holders for medium and large furnaces, an electrode holder utilising prebaked
carbon electrodes, a specialised, long-life freeze-lining for furnaces, reliable extra-heavy-duty post-taphole
equipment and operator-training software.For the processing of fine ores and metals, BATEMAN’s direct-current (DC) arc technology offers the
possibility of accurate process control and relative independence of the power input in relation to the
type of feed material. DC technology enables the recovery of value from manganese wastes, stainless-
steel and steel-plant dusts and further development is underway in collaboration with Mintek for ferronickel
smelting, zinc fuming and base-metals processing.Ongoing improvement of the metal from-slag recovery expertise, based on BATEMAN’s Apic jig technology,
ensures market leadership. New and proven fines-beneficiation techniques, integrated into the systems
currently being delivered, enhance recoveries and facilitate effluent treatment.The project management and support services offered includes bankable documents, process development,
design and detail engineering, procurement, manufacture, equipment supply, erection and commissioning
and they are carried out on a turnkey, managed contract or partnering basis.First tap of ferrochrome at SA Chrome
SA Chrome’s first furnace at the Boshoek site near Rustenburg, RSA, was fired up on 9 June 2002,
with the first tap of charge ferrochrome being tapped on 13 June. By mid July, less than one month
later, when 100 taps of metal had produced 2 800 t of saleable product, the furnace had already been
ramped up to a power consumption of 48 MW.This greenfield plant has been installed in the remarkably short time of 15 months, the contract for the SA
Chrome smelter having been awarded to BATEMAN at the end of March 2001 and the first steelwork
having been erected on site a mere four months later.When completed, the smelter will consist of two 54 MW closed submerged arc furnaces and a pelletising
and sintering plant to process 520 000 t/y of a blended feed of chromite and chrome concentrate.The next major components on the project schedule are the second furnace and the sinter plant producing
a feed of sintered pellets for the furnaces. Construction is progressing well and commissioning should be
completed by the end of August.Safety on track at SA Chrome
On 28 February 2002, the site personnel installing the R700M turnkey ferrochrome smelter for SA Chrome
at the Boshoek site near Rustenburg, RSA, celebrated the significant achievement of half-a-million manhours
without a lost-time injury.The activities at the site have recently been ramping up rapidly, and the 1 286 persons on site during the
celebrations will increase to a peak of about 1 500 during mid-March,” explained Jonathan Such, Senior
Project Manager. “The preservation of life and limb is our prime objective, so it is always with a sense of
relief and satisfaction that we achieve these important safety milestones during large projects.“Accordingly a comprehensive safety campaign led by the project’s safety consultant is maintained,” said
Such. “This involves induction training for all new personnel on site, lectures on safety and tool-box talks.
To further promote ongoing vigilance, a safety competition based on the comparison of regular safety
audits is organised between all of the main contractors.”The site’s staff complement comprises mainly semiskilled and unskilled labourers, with a few artisans.
In terms of the project contract, the use of local labour has been maximised, with a large proportion of the
personnel having being drawn from the local labour market. There are about a dozen large contractors
on site, providing services in respect of civil, mechanical erection, piling, structural, electrical-
instrumentation and specialist-refractory installations.“Aside from three days lost, due to inclement weather which resulted in the temporary flooding of
portions of the site, good advances have been made on the construction and we are well positioned
to put up a record time for this type of project,” claimed Such. “From the time the first steel was erected
in early August 2001 to now, more than 4 000 t of steel have been delivered to site and 3 200 t erected.The civil works have required 710 piles to be placed, 61 000 m3 of ground excavated, 125 000 m3 of
soil replaced, 60 000 m3 of concrete poured, utilising 18 000 m2 of shuttering, and 1 200 t of reinforcing
steel and 4 500 m of piping have now been installed. The main furnace building has topped out at 60 m
high and towers over the surrounding landscape.”New ferrochrome smelter for Assmang
A consortium of Bateman Titaco and Outokumpu Engineering Contractors Oy has supplied a new smelter
at Assmang Chrome Division's Machadodorp Works, Mpumulanga, RSA. The plant uses the latest
technology in agglomeration, sintering and preheating of the feed ore supplied to the furnace, resulting
in improved chromium recovery and a lower consumption of kilowatt hours per tonne of metal produced.
Furnace stability and ease of operation during smelting are also enhanced.
This R300M turnkey contract for Assmang Chrome, an Avmin / Assore joint venture, effectively doubles
the ferrochrome output at the Machadodorp plant to about 300 000 t/yr . The smelter includes a 54 MVA
furnace, a preheater and a 350 000 t/yr pelletising plant.
The submerged-arc closed furnace is a Bateman Titaco design and features Bateman Titaco electrode
holders using Söderberg paste. A significant advantage of this design is that the smelting process
does not generate significant amounts of toxic chromium six. With a pretreated charge the furnace
can be sealed gas tight. It also reduces environmental pollution as the process gas is cleaned,
rendering it suitable for use as a heating fuel.
A feature of the furnace is its freeze lining, which is expected to extend the campaign life of the furnace
lining considerably. A Bateman Titaco mudgun and taphole drill unit was also supplied. The mudgun
is electrically operated and eliminates any potential fire hazards in front of the taphole. The drill is
pneumatically operated.
The preheater and pelletising plant embody Outokumpu technology and supply the furnace with
sintered pellets, significantly increasing chrome recovery and reducing electrical energy consumption.
The fine-ore feed to the plant is milled and filtered to remove excess water, mixed with a binder and
passed into a pelletising drum to produce green pellets of between 10 and 15 mm. Under- and
oversized pellets are reprocessed.
The green pellets are fed to an energy-efficient steel-belt sintering furnace and are dried, preheated,
sintered and cooled to produce sintered pellets with a hard and porous structure and excellent high-
temperature strength. The pretreated pellets now contain iron in a readily reducible form and the
high specific surface of the finely ground chromite increases the reduction rate in the smelting furnace
and avoids non-uniform reduction. The cooled pellets are stored on stockpiles, part of which is used to
form a protective under-layer in the sinter machine and the balance sent to the furnace for smelting.
The hot gases from the cooling compartments are recycled to the drying, preheating and sintering
compartments and greatly improve the energy efficiency of the sintering system. The decomposition
of the volatile hydroxides and carbonates during sintering also reduces the demand for electrical
energy during subsequent smelting in the furnace.
Stockpiled sintered pellets, with other raw materials, are conveyed and fed into a preheater above
the furnace. Here the pellets are heated to a temperature of 600 °C by combusting the scrubbed
gases captured in the furnace. Preheating the pellets reduces the electrical energy consumption
of ferrochrome production by about 20 % compared to conventional plants. It also increases the
capacity of the furnace, results in a smoother arc-furnace operation and reduces electrode
consumption and maintenance downtime.
A building 60 m high had to be constructed to house both the furnace and the preheater. Being
essentially a brown-fields project, care had to be taken not to disrupt ongoing production at the
works. The contract for the project was awarded in June 2000 and completed in October 2001
with the opening ceremony for the new smelter held on 29 January 2002. The furnace took 14
months to complete and the pelletising plant a further two months.
A very similar project was completed in 1999 by Bateman Titaco and Outokumpu Engineering
Contractors Oy for Hernic Ferrochrome and has been followed by another, but of double the size,
for SA Chrome, due for completion later this year.
TEMCO’s ferromanganese furnace in Tasmania
The Tasmanian Electro Metallurgical Company (TEMCO), which is part of Samancor, South Africa and
located near Georgetown in Tasmania, has awarded Bateman Titaco a US$1,8M turnkey contract to
refurbish its No1 furnace. The objective of the project is to increase the operation period between relines.The full scope of the contract covers the furnace shell and its lining, the water-cooling system round the
shell, as well as the grillage support and the bottom air-cooling system. BATEMAN is responsible for
the design, procurement and installation. A local Tasmanian contractor under BATEMAN supervision
will install a state-of-the-art carbon and graphite refractory ‘freeze’ lining in the furnace obtained from
Ucar Carbon, USA. The combination of water sidewall cooling and efficient heat dissipation by the lining
lowers the lining temperature to below that of the molten metal, resulting in a layer of solidified slag and
metal. This layer protects the furnace lining from erosion, chemical attack, thermal shock and other
stresses, greatly extending its useful life. These freeze linings are thinner than conventional linings
and result in larger-diameter hearths. Besides the increased capacity, these linings also permit
increased furnace power and generally improve furnace operation.This lining technology is well-proven by BATEMAN in several RSA-based plants, having been used for
Hernic’s third ferrochrome furnace near Brits and for Assmang’s ferrochrome furnace at Machadadorp;
it has also been chosen by SA Chrome for its two new 54 MVA ferrochrome furnaces at Boshoek which
are currently under design and construction by BATEMAN. The Temco furnace will be shut down in early-
May for a seven-week period to complete the refurbishment.SA Chrome's ferrochrome smelter contract
Bateman Titaco has been awarded a lump-sum turnkey contract by SA Chrome and Alloys Limited for
its new smelter, pelletising and sintering plant at Boshoek, some 20 km north of Rustenburg, North West
Province, RSA. The plant will be designed to produce 235 000t/yr of saleable charge ferrochrome from a
blended feed of lumpy chromite and chrome concentrate. Importantly, Bateman Titaco was instrumental
in preparing the bankable feasibility study for the project and also facilitated the off-take agreement for
the ferrochrome product. These aspects ensured that the client was able to raise the necessary equity
and loan finance for the project.
The smelter consists of two 54 MVA closed submerged-arc furnaces and a pelletising and sintering plant
to process 520 000 t/yr of material. The furnaces will be designed by Bateman Titaco and are similar to the
recent smelter supplied to Hernic Ferrochrome and Feralloys Limited, Machadodorp.
The new, but proven, Bateman Titaco closed furnace technology with Outokumpu pre-heating was chosen
because it is environmentally friendly. Smelting of chromite during the production of ferrochrome could lead
to the production of chromium (VI), which is highly toxic. However, closed furnaces preclude the ingress of
air (oxygen) into the hot interior, so that chromium (VI) cannot be formed.
Outokumpu's sintered-pellet smelting process is proven technology developed at its ferrochrome plant in
Tornio, Finland. This process route improves chromium recoveries by 5 % and consumes 25 % less
energy than conventional open or semi-closed furnaces, ensuring that SA Chrome will be the lowest
cost chromium producer. The lower energy consumption also reduces the ecological impact associated
with fossil fuel electric energy generation. Two ore types will be blended in the plant, viz. a high grade LG6
and a lower grade UG2 ore. The LG6 ore will be brought by road from SA Chrome's Horizon mine, located
some 40 km to the northwest of the smelter, and UG2 concentrate, a discard product from platinum mining,
will be purchased from a nearby platinum producer. A blend of about 40 % LG6 ore and 60 % UG2
concentrate will be fed to the furnaces.
Bateman Titaco conducted the project's feasibility study and was also responsible for the environmental
impact study. The proposed capital expenditure on the whole project is R700 million, of which R300
million is earmarked for the two furnaces, R175 million for the pelletising and sintering plant and
R60 million for the plant's infrastructure.
It is estimated that the furnaces will need respectively 13 and 15 months for construction and
commissioning with the pelletising and sintering plants requiring17 months. The first sales of
products should commence at the end of the first quarter of 2002.The Hernic Ferrochrome Project
Bateman Titaco Limited has engineered, supplied and constructed one of the most sophisticated
charge-chrome producing plants in the world for Hernic Ferrochrome(Pty) Ltd. he state-of-the-art
technology together with the benefits of large-scale production have enabled Hernic to improve
its competition have advantage by improving the stability of its furnace operation, increasing
chrome recovery and saving energy.The project is part of Hernic’s long-term business strategy. As a result of this expansion it will be able to
maintain its position as the third largest producer of ferrochrome in South Africa and be a global player
with one of the lowest production costs for charge-chrome in the world.The project involved installing a new submerged arc furnace, preheating and sintering plants, ball ills,
conveyors and overhead cranes. Rated at 54MVA,the furnace which is the largest ferrochrome smelter
in Southern Africa, constituted about half the total cost of the expansion project. Bateman Titaco also
installed the first two furnaces at Hernic, two 37 MVA fine smelting units, which were supplied in 1994.
The process technology for the new furnace combinesOutokumpu’s ore sintering and furnace charge pre-heating processes. Bateman Titaco designed
the large closed-type submerged ore smelter in close collaboration with Hernic and Outokumpu.SMELTING
The furnace is fed with sintered pellets comprising finely ground ore sintered with coke and fixed with
other raw materials. The resulting pellets are then heated to a temperature of 700 °C. The preheating
reduces the energy consumption during ferrochrome production by between 20 % and 30%
compared to conventional plants.Sintered pellets also significantly increase chrome recovery and reduce electrode consumption.
The pellets contain finely ground chromite with a high specific surface which increases the reduction
rate and avoids non-uniform reduction. The rapid smelting, improved furnace stability, ease of operation
and high chromium yield mean that pre-treatment costs are quickly recovered. The absence of moisture
and other volatiles in the smelting furnace together with better gas permeability of the burden (from the
use of pellets instead of fines) reduce eruptions and hence furnace downtime.Bateman Titaco designed and constructed the 54 MVA furnace including all of its infrastructure.
A vital technology component in the furnace is the Bateman Titaco electrode holder, designed
specifically for closed submerged-arc furnaces using Söderberg paste. The electrically actuated
lipping device provides a fail-safe means of holding the electrode in position even if the electric
power fails. The contact shoes through which electricity flows into the electrode can be lifted
above the furnace cover and a section of the heat shield removed, greatly facilitating and
speeding up maintenance. The level of protection afforded the furnace components enables
it to operate continuously at 900°C and higher.The process gas from the closed smelting furnace is cleaned using two wet scrubber units,
rendering it suitable as a heating fuel by burning by-product carbon monoxide. Some of this
gas is used in the sintering process and for pre-heating the smelter feed. The remaining gas
is used or general heating or drying purposes or is flared if not usedPelletising and sintering The new plant installed at Hernic feeds both the new 54 MVA furnace as
well as the existing two 37 MVA units and has been designed to improve the availability,
performance and production volumes.The ore and coke are ground to 90% minus 200 mesh, graded, filtered to remove excess water,
mixed with bentonite and pelletised in a drum. Green pellets between 10 and 5 mm are fed into a
steel-belt sintering furnace at temperatures up to 1350°C and passthrough drying, preheating,
firing and cooling zones. The pre-treated pellets containing iron in its more easily reducibleTechnology gives Hernic Ferrochrome the edge
Titaco Projects, a BATEMAN subsidiary, is currently engineering, supplying and constructing one of
the most sophisticated charge chrome producing plants in the world for Hernic Ferrochrome (Pty)
Ltd. The process technology used combines Outokumpu’s ore sintering and furnace charge
preheating processes with a large closed type submerged ore smelter designed by Titaco in
collaboration with Hernic, Outokumpu and Tanabe Corporation. It will be the largest furnace
of this type in South Africa.
Hernic, currently the third largest producer of ferro-chrome in South Africa, is expanding its operations
to become not only one of the global players but one of the lowest-cost producers of charge chrome
in the world. This state-of-the-art technology, together with the benefits of large scale production,
will result in Hernic further improving its competitive advantage through improved stability of the
furnace operation, increased chrome recovery and overall energy saving.
The technology for the pretreatment and agglomeration of the ore ensures improved furnace
stability and ease of operation during smelting. Pellets of the correct strength and size are sent
to sintering where proper conditions in the furnace ensure a hard but porous structure important
for improved rate and efficiency of reduction. The high specific surface of the finely ground chromite
increases the reduction rate in the smelting furnace and avoids non-uniform reduction. The pretreated
pellets contain iron in its more easily reducible ferric form and their porous structure and high
temperature strength improves solid state reduction. The volatile hydroxides and carbonates
decompose during sintering, reducing the demand for electrical energy in the smelting phase.
Pelletising and sintering thus produce energy savings in smelting as the costs incurred are
quickly recovered in more rapid smelting and a high chromium yield. In the furnace the hot
gases from the cooling compartments are recycled to the drying, preheating and sintering
compartments, thus improving energy efficiency.
The process gas from the closed smelting furnace is cleaned by two wet scrubber units, rendering
it suitable as a heating fuel. Some of this gas is used in the sintering process and for preheating
the smelter feed. The rest of the gas can be used for general heating or drying purposes or flared if not used.
A major reduction in electrical energy consumption results from preheating with gas instead of using
electricity for this purpose as in the normal smelting process. Charge preheating also significantly
increases smelting capacity and reduces electrode consumption. The absence of moisture and
other volatiles in the smelting furnace together with better gas permeability of the burden (from the
use of pellets instead of fines) reduces eruptions and hence furnace downtime.
These features combine to yield improved availabilities, optimum furnace performance and
increased production volumes for the overall plant.
The fact that Hernic adopted this process as part of its long term strategy will certainly put it in a very
strong competitive position. Given current market conditions when the plant is commissioned,
Hernic will be amongst the few producers equipped to weather the storm.
Extracting value from ferro-alloy plant waste
Titaco Projects Limited, a BATEMAN subsidiary, has a complete waste management system available
to enable ferro-alloy plants to comply with all environmental regulations. This will not only protect the
environment, but could extract value from those process streams previously considered to be
waste material.
Projects are generally approached by aiming for zero effluent and then, if necessary, compromising in order
to meet the requirements within budgetary restrictions. Key factors considered are effluent quality, solid
residue quality, toxicity and the best available process routes.
The normal solid / liquid waste management process currently involves chemical treatment, de-watering
and dumping of inert solids, with only the effluent water being recycled. Titaco’s approach is to also maximise
the recycling of these solids without detrimentally affecting the process.
In the case of ferro- and silico-manganese waste products, the process water is recirculated and the
generated solids can also be re-introduced into the smelter to add value to the process. Most manganese
dusts are fairly high in manganese and low in iron and can be used as raw material for either silico-
manganese production or, in cases where the manganese content is sufficiently high, as a replacement
for special ‘high grade’ ores which normally have to be imported. These are, however, generally very fine
and not easily handled in traditional smelters. Titaco now has a novel means to process these dusts, as
well as other metal fines, directly into saleable products.
Titaco’s approach also encompasses maximum utilisation of process off-gas, e.g. by closing the furnace
roof and recovering and cleaning the unburnt gas. The calorific value of the clean gas can then be
employed to improve the overall energy efficiency of the plant. This use not only improves the plant’s
energy efficiency, but reduces the cost of cleaning large volumes of burnt gas.
Titaco expands Hernic ferro-chrome production
Titaco Projects Limited, a BATEMAN subsidiary, has been awarded a 200M turnkey contract by Hernic
Ferrochrome for a third charge chrome furnace near Brits, RSA. This will double Hernic’s production
capacity to 260 000 t/yr and place it within the top five global producers of ferro-chrome (FeCr) and,
more importantly, at the forefront of low cost production by virtue of a new but proven ore pre-
treatment process.
This expansion will embody the most modern design and includes a sophisticated 350 000M t/yr
pelletized ore sintering process and a 54 MVA closed furnace. The process will also enable Hernic
to use the large quantity of fines produced in its opencast mine as well as previously discarded lower
grade ores. The new furnace will have a capacity of 110 000 t/yr of charge chrome. Surplus sintered
chromite fed into Hernic’s existing two furnaces will result in a further 10 % to 15 % capacity to boost the
total increase in production to 150 000 t/yr .
Optimizing production cost by means of chrome recovery and energy utilization is an important part of the
project objective. Consequently Hernic selected Outokumpu’s FeCr technology which has been
successfully used at Outokumpu’s Torno smelter for several years and has also been installed at
Samancor, RSA. Outokumpu will be responsible for the supply of the pelletizer and pre-heater and
will provide the necessary operational support and expertise.
The contract was awarded to Titaco on the strength of its considerable expertise and experience in
the Southern African ferro-alloy industry and because of its leading role in the installation of Hernic’s
first two furnaces. Titaco will design and construct the furnace and all related services and provide all
required service guarantees. A strong team from Hernic and Titaco will co-operate the project in the
same way the first two Hernic furnaces were handled, which were constructed on time and within budget.
Work commenced in March 1998 and when commissioned around mid-1999 it will be the largest
Ferrochrome FeCr furnace in RSA.
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