Assessment of utilized technologies

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Project PREWARC
Faculty of Technologymetallurgy University Sts
Cyril Methodius
P R E W A R C
Assessment of utilized technologies for
preserving water quality
TMF-Skopje, 2007
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Project PREWARC
Faculty of Technologymetallurgy University Sts
Cyril Methodius

• OBSERVED INDUSTRIES
• Metallurgy
• Mines
• Electric power plant

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Project PREWARC
Faculty of Technologymetallurgy University Sts
Cyril Methodius
M e t a l l u r g y

• FENI
• Problems Filter dust, EAF slag, converter slag,
  Atmospheric leaching of the slags, gas emission
• MAKSTIL
• Problems Filter dust, EAF slag, Ladle slag,
  Atmospheric leaching of slags, gas emission
• SILMAK
• Problems Furnaces are without gas cleaning
  system

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Project PREWARC
Faculty of Technologymetallurgy University Sts
Cyril Methodius
Electric Power Plants

• REK Bitola
• Problems Fly ash (hazardous)
• REK Oslomej
• Problems Fly ash (hazardous)

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Project PREWARC
Faculty of Technologymetallurgy University Sts
Cyril Methodius
M I N E S

• Zletovo
• Sasa
• Toranica
• Bucim
• Problems Solid waste - Tailings, Atmosferic
  leaching of solid waste, Pollution of underground
  water and soil, and Atmospheric emission

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Makstil, Skopje
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Comparison of the current performances with BAT
Emission of primary gases The emission of
primary gases from the electric arc furnaces is
about 95 from the total emission of gases
created during the manufacture. Most of the steel
production plants use electric arc furnaces with
three electrodes, where the extraction of the
primary gases is carried out through so called
fourth hole. That is why, 85 to 90 of the gases
created during the process, starting from the
charging until the moment the metal is tapped,
can be captivated and cleaned. Even today, we
can find electric arc furnaces that are consisted
only by so called dog-house that is they are
without the fourth hole. More than 50 from the
electric arc furnaces used today, instead of
fourth hole, use additional system for evacuation
of gases from the units atmosphere, mostly with
ventilation hoods.
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Electric arc furnace with fourth hole Dog
house for captivation of the gases And hood for
de-dusting of the units and dust from the
electric arc furnace atmosphere
Figure 1. Systems for de-dusting from the
electric arc furnace
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Primary emission, BAT Makstil results of the
comparisons
Electric arc furnace The electric arc furnace
for production of steel used in Makstil Skopje
uses system of three carbon electrodes. The
furnace has built on fourth hole for extraction
of the primary gases. The problem of the removal
of fugitive gases is not yet solved, that means a
system for their captivation is not included. The
secondary gases made during the charging,
smelting and tapping of the metal can not be
captivated.
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Comparison of the values recommended by BAT and
the current results for primary emission from the
electric arc and ladle furnace in AD Makstil
Skopje
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Secondary emission of gases from charging,
tapping of metal and continuous casting
Values for secondary gases created during
transportation and charging, tapping of the metal
and continuous casting, recommended by BAT, that
are not a subject of Makstils analysis
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Project PREWARC
Faculty of Technologymetallurgy University Sts
Cyril Methodius
Optimal approach towards BAT For optimal
approach or achievement of the measures
recommended by BAT, during the steel production
in electric arc furnace, we should use BAT
techniques (methods) or their combination. Which
one of the techniques (methods) or their
combination will be used, depends on the local
possibilities.
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Recommended measures

• Extraction of dust in electric arc furnace
• With combination of direct extraction with forth
  hole and a system of canopy hood,
• Dog-house and a system of canopy hood, or
• Complete evacuation of the unit.
• By applying one of these techniques or their
  combination, we expect that the degree of the
  dust and gas captivation would be higher than
  98.
• The further treatment of the steel is performed
  by using ladle technique in a ladle specially
  used for this purpose. The fugitive gasses that
  have been produced during this process are not
  extracted, which means there is no system for
  their collecting.

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Project PREWARC
Faculty of Technologymetallurgy University Sts
Cyril Methodius
De-dusting of the waste gasses A well-designed
bag filter can provide less than 5mg/Nm3 for new
factories and less than 15mg/Nm3 for factories
that have been operational some period of
time. The decrease of the dust quantities is
related to the decrease of heavy metals
emission, but this does not include the heavy
metals that are present in the gas phase, as the
mercury. In AD Makstil the dust and gas
extraction in the furnace is performed by using
system with bag filter. For this, no greater
investments are needed.
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Project PREWARC
Faculty of Technologymetallurgy University Sts
Cyril Methodius
Decrease of PCDD/F and PCB emission Adequate
system of post combustion equipped with system
for collecting gasses or in special system for
further combustion with quick cooling in order to
prevent the synthesis that could happen again.
Injection of lignite dust before entering the
bag filter By applying one of the recommended
techniques, we expect the gas emission to
decrease to 0.1-0.5 ng I TEQ/Nm3. .
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Faculty of Technologymetallurgy University Sts
Cyril Methodius
Project PREWARC

• Decrease of the solid waste
• Recommended BAT techniques
• Minimization of the waste from the production
• Decrease of the solid waste by recycling of the
  slag from the electric arc furnace and the filter
  dust. Depending on the local possibilities, the
  filter dust can be recycled and up to 30 Zn can
  be obtained from it. The filter dust with more
  than 20Zn can be used in the non-ferrous
  metallurgys industries.
• For solid waste that can not be recycled, the
  only option is controlled disposal.

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Project PREWARC
Faculty of Technologymetallurgy University Sts
Cyril Methodius

• Decrease of the fugitive emission by manipulating
  with materials
• Change of the transportation system
• Maintenance of the transportation roads
• Maintenance of the units inner, by using
  industrial vacuum cleaner
• Covering of the storages
• Captivation of the dust produced by the usage
  of dolomite in a ladle, etc.

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Faculty of Technologymetallurgy University Sts
Cyril Methodius
SILMAK, Skopje
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Faculty of Technologymetallurgy University Sts
Cyril Methodius
BAT for receiving, storing and transportation

• In order to prevent the destroying and pouring of
  the material, the transportation systems,
  conveyers and pipes should be well secured
• To inhibit the dust emission during
  transportation in open transportation systems,
  they should include equipment for extraction and
  dust filtration
• Regular cleaning and washing of the vehicles and
  transportation systems should be performed
• Regular control and inspection of the
  transportation systems
• Control its humidity
• Insuring appropriate and regular maintenance

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Faculty of Technologymetallurgy University Sts
Cyril Methodius

• The analysis of the data obtained from Silmak and
  our own investigations show that the most
  important and necessary measures are
• Closing of the open transporters
• Equipment for cleaning plants surroundings
• De-dusting of the transfer stations.

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Faculty of Technologymetallurgy University Sts
Cyril Methodius
Primary measures for cleaner production of
ferrosilicon in open and half-closed
furnaces The results obtained from Silmaks data
show that the air flow is twice as bigger than
the one recommended by BAT. For approaching and
achieving these values recommended by BAT, during
ferrosilicon production in electric arc furnaces,
some interventions on the system for gas
extraction should be taken over, that is to
redesign the regime of gas extraction. The
furnaces are not equipped with a system for
extraction of gases and dust created during
charging, of the fugitive gases created during
smelting and of gases created during metals
tapping. To inhibit the environment pollution of
the plants surrounding with dust and gases that
are released through out the chimneys, a system
for captivation and cleaning of the gases bag
filter should be installed.
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Faculty of Technologymetallurgy University Sts
Cyril Methodius

• Control of the process
• The most important parameters which should be
  controlled during the smelting process are
• Control of the furnaces work in order to optimize
  the working conditions. The key parameters which
  should be controlled are the pressure and the
  temperature on different parts in the furnace and
  the oxygen and CO concentration.
• Control of the process is carried out by using
  relevant methods which allow undisturbed
  maintenance of the working conditions on an
  optimal level.
• The operators of the devices should be
  appropriately trained and informed about the
  procedures and parameters which should be
  controlled.
• Appropriate maintenance of the devices, the
  de-dusting systems and all the other following
  processes.

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Faculty of Technologymetallurgy University Sts
Cyril Methodius

• Decrease of the fugitive emission from materials
  manipulation
• Maintenance of the road network
• Maintenance of the transportation roads
• Maintenance of the units inner, by using
  industrial vacuum cleaner
• Covering the storages of loose materials
• Captivation of the dust produced by using
  dolomite in a ladle, etc.
• Contamination of water
• In the technological process of cooling there is
  no contamination of water, and because of this no
  treatment of the water is necessary.
• For the needs of the technological process
  cooling of the furnaces transformers, sanitary
  water is also being used.
• There are no wastewaters

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ZLETOVO Mine
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Figure 1.The general location of the Zletevo
lead/zinc mine
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project PREWARC
Faculty of Technologymetallurgy University Sts
Cyril Methodius
BAT - RECOMENDATION
T a i l i n g s
It is recommended that an integrated pollution
prevention and control (IPPC) approach is applied
to planning for the future improvements at the
Zletovo mining facilities. Thus, air and
wastewater pollution controls should both be used
(rather than either one form of abatement or the
other being predominant), to achieve
environmental improvements and compliance with
the legislation.
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project PREWARC
Faculty of Technologymetallurgy University Sts
Cyril Methodius

• 1.Tailings
• Recommendation
• Application of an integrated pollution
  prevention and control (IPPC) for the future
  improvements at the Zletovo mining facilities.
  Thus, air and wastewater pollution controls
  should both be used (rather than either one form
  of abatement or the other being predominant), to
  achieve environmental improvements and compliance
  with the legislation.
• 2. Particulates
• Recommendation
• The particulate wastes inside and outside the
  crushing building should be removed from the site
  and treated as hazardous wastes.
• The conveyors should be appropriately enclosed.
• Active ventilation with effective filters or
  scrubbers should be installed in the crushing
  area.
• The older areas of the tailings should be covered
  with a suitable soil.

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Faculty of Technologymetallurgy University Sts
Cyril Methodius
project PREWARC

• 3. Odour
• Recommendation
• Instalation of active ventilation systems with
  effective filters in the areas where the odour
  emissions are high.
• 4. Solid Waste and Sludge Management
• 4.1 General Wastes
• Recommendation
• Disposing of the remaining scrap metal and other
  inert wastes of off-site, preferably for re-use
  or recycling.
• 4.2 Hazardous Wastes (Other than Tailings)
• Recommendation
• Construct of a specific hazardous waste disposal
  facility. This should be appropriately located
  be lined and bunded to reduce the possibility for
  migration of any spills and be covered to
  eliminate rainwater ingress.

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Faculty of Technologymetallurgy University Sts
Cyril Methodius
project PREWARC

• 4.3 Tailings
• Recommendation
• To develop a further tailings disposal site in
  the vicinity of the Zletovo mine, and do not
  employ the current disposal site (except perhaps
  for a short temporary period when the new
  disposal facility is being constructed - this to
  be specifically agreed with the Government
  authorities).
• Water Supply and Wastewater Discharges
• These discharges should not be introduced into
  the mine wastewaters.

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Management of tailings and waste-rock
Reduction of emissions to water Re-use of process
water Dissolved metals treatment Suspended solids
and dissolved components Acid / Alkaline water
treatment Groundwater monitoring Dams Techniques
to design, construct and raise dams Monitoring
the stability of dams and heaps Uses of tailings
and waste-rock Earth construction hydraulic
engineering landfill construction further
applications (brick industry - ceramic processes)
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WATER TREATMENT TECHNOLOGIES

• Neutralization with adding of some agents
  (Lime, Ca(OH)2..)
• Leaching and Extraction (cementation, ...)
• Electrorecavery neutralization
• Ion exchange of underground water (Na, Cl)

• REMEDIOATION OF HISTORICAL TAILINGS DISPOSAL
• profiling, as required
• covering or capping, and
• revegetation

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SASA Mine
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Faculty of Technologymetallurgy University Sts
Cyril Methodius
project PREWARC

• 1 Chemical Storage
• Recommendation
• All old and empty chemical drums should be placed
  in a secure area with other hazardous waste
  materials.
• The floor of the chemicals store needs to be
  excavated, and this material should be placed in
  this secure hazardous waste area.
• New chemical drums should be placed in a secure
  bunded area under cover, with segregation by
  chemical type.
• Control over the use of chemicals in the dosing
  area needs to be improved.
• 2.Particulates
• Recommendation
• To remove from the particulate wastes inside and
  outside the crushing building and treate them as
  an hazardous wastes.
• The appropriate enclosing of conveyors.
• To cover the older area of the tailings with a
  suitable soil.
• 3, Odour
• Recommendation
• Instalation of active ventilation systems with
  effective filters in areas where odour emissions
  are high.

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Faculty of Technologymetallurgy University Sts
Cyril Methodius
project PREWARC

• 4. Solid Waste and Sludge Management
• 4.1.General Wastes
• Recommendation
• Despousing of off-site of remaining scrap metal
  and other inert wastes preferably for re-use or
  recycling.
• 4.2. Hazardous Wastes (Other than Tailings)
• Recommendation
• To construct a specific hazardous waste disposal
  facility. This should be appropriately located
  be lined and bunded to reduce the possibility for
  migration of any spills and be covered to
  eliminate rainwater ingress.
• 4.3. Tailings
• Recommendation
• To develop a further tailings disposal site in
  the vicinity of the Sasa mine, and do not employ
  the current disposal site (except perhaps for a
  short temporary period when the new disposal
  facility is being constructed - this to be
  specifically agreed with the Government
  authorities

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Faculty of Technologymetallurgy University Sts
Cyril Methodius
project PREWARC

• 5. Water Supply and Wastewater Discharges
• To design and construct a wastewater treatment
  plant, to accept and treat all wastewaters
  arising at the Sasa mine facilities and
  containing significant quantities of
  contaminants. This must include the wastewaters
  arising from the adits the mine buildings and
  processing areas and any leachate arising from
  the new tailings disposal facility. The
  wastewater discharge standards to be achieved by
  the treatment facility will be as laid down by
  the MoEPP.
• 6. Housekeeping
• Recommendation
• The materials that constitute hazardous wastes
  need to be stored in a secure area, with
  safeguards against leakage into the general
  environment.

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TORANICA Mine
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Faculty of Technologymetallurgy University Sts
Cyril Methodius
project PREWARC

• 1. Chemical Storage
• Recommendation
• All old and empty chemical drums should be placed
  in a secure area, with other hazardous waste
  materials.
• The floors of the contaminated chemicals store
  need to be cleaned, and this material should be
  placed in this secure hazardous waste area.
• New chemical drums should be placed in a secure
  bonded area under cover, with segregation by
  chemical type.
• Chemical drums should only be stored where their
  use is essential around the site.
• Control over the use of chemicals in the dosing
  area needs to be improved, with bonding provided
  to contain spills.
• 2. Particulates
• Recommendation
• If they cannot be recycled, the remaining
  particulate wastes inside and outside the
  crushing building should be removed from the site
  and treated as hazardous wastes, before
  operations are restarted.
• The damaged conveyors should be appropriately
  enclosed.
• Active ventilation with effective filters or
  scrubbers should be installed and/or repaired in
  the crushing area.
• The older area of the tailings should be covered
  with a suitable soil. This will reduce dust
  arising in windy conditions, and will assist in
  the revegetation of the tailings disposal area.

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Faculty of Technologymetallurgy University Sts
Cyril Methodius
project PREWARC

• 4. Odour
• Recommendation
• Installation of active ventilation systems with
  effective filters should be installed in areas
  where odour emissions are high. This will
  improve both environmental and Health Safety
  conditions.
• 5. Solid Waste and Sludge Management
• 5.1 General Wastes
• Recommendation
• To remaining scrap metal and other inert wastes
  should be disposed of off-site, preferably for
  re-use or recycling.
• 5.2. Hazardous Wastes (Other than Tailings)
• Recommendation
• Construction of a specific hazardous waste
  disposal facility. This should be appropriately
  located be lined and bonded to reduce the
  possibility for migration of any spills and be
  covered to eliminate rainwater ingress. In the
  longer term, a more coordinated hazardous waste
  management system will need to be developed, in
  line with the Macedonian national programme for
  addressing hazardous wastes.

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Project PREWARC
Faculty of Technologymetallurgy University Sts
Cyril Methodius
Thank you for your attention!