KAYMAZ GOLD MINE
PLANT
Crushing- Grinding Unit:
Ore received from open pit is transferred to ore bin with capacity of 100 tones then passes
through conveyor to reach the crusher. Ore crushed in primary jaw crusher goes to double layer
screeners 50 mm and 20 mm each. Ore above 22mm is fed back to second cone crusher
22mm under screen and stored in fine ore bin.
Water is sprayed onto ore in the bin to supress dust that may generate while ore fed to ore bin.
Same process is carried out at jaw crusher where the ore is fed into.
Jaw crusher,discharging points, conveyor and transferring poins, top of the cone crusher, top
of screen are completely covered and sucked air passes through two dust collecting units.
Grinding unit:
To maintain required liquid-solid level in leach tanks, ore from crusher need to be ground down
to 75 micron. This is why ball and rod mills are used, operating with cyclone in closed circuit.
Grinding process in rod mill is carried out with rods 90 mm diamater. In ball mill process, 40
and 50 mm diameter steel balls are used for grinding. As the grinding is a wet process system
and no chemicals are added into the system at this stage, it is not necessary to take
environmental measures other than those mentioned above within workers health and job
safety requirements. Unit is surrounded by concrete fence and pump is placed on concrete
platform. Any spills from the unit are collected in the pump box and pumped backed to the
system by cleaning pumps. Ore density is hourly checked in grinding unit. Furthermore, many
values such as mill loads and cyclone pressure are monitored by computersystem.
Leach and Adsorption Unit
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KAYMAZ GOLD MINE
PLANT
Ground to 75 micron, ore is sent to leach tanks in slurry condition to be mixed with cyanide.
Cyanide dissolution and pure oxygen are given to the slurry in leach tanks to dissolve gold and
silver in water. Gold and silver in reaction with cyanide and oxygen are dissolved into water.
Gold and silver in solid form reacting with cyanide and oxygen are dissolved in water. Active
carbon is added to to seperate gold and silver from slurry full active carbon holding gold and
silver is separated from slurry by special screens. Cyanide slurry is sent to chemical
decomposition unit to be treated and gold and silver loaded carbon is sent to Elution Unit for
recovery of gold and silver.
Workers Health and Job Safety:
In addition to the personal protective equipment used by the operators for above duties, number
of safety showers is placed in the unit to be used in case of contact with chemicals and slurry.
Elution Unit
Elution and gold room consists of 4 tons of elution
column with 4 tons of carbon capacity, activation
furnace with 250 kg/hour capacity, 2 party
electrolysis cells, Smelting furnace and inducing pot
solution tanks,
Solution loaded with gold and silver in electrolysis
tanks passes through electrolysis cells and recycled.
Gold and silver in solution are collected on cathode
cells in solid form under high electricity current . Gold
and silver collected on electrolysis cells are washed
with high pressure water and filtered and dried in
drying furnace. Dried gold and silver are poured into
induction pot and final product dore metal is
obtained.
Chemical Decompositon Unit
Chemical decomposition unit consists of three stages:
-
Cyanide decomposition
Heavy metal stabilization and
Tailing recycling water stabilization and decomposition of spills.
To comply with the limits defined by the Ministry of Environment, tailing pulp from leach and
adsorption units are decomposed in the decomposition unit before being discharged to tailing
pond.
Cyanide Decomposition
In first stage, free and metal cyanide compounds (excluding iron cyanide compounds) turn into
cyanate with sodium metabisulphide in INCO process. Cyanates are then hydrolyzed and form
carbonate and ammonia. Iron cyanide compounds are precipitated and stabilized. Optimum pH
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KAYMAZ GOLD MINE
PLANT
8.5 is automatically adjusted with hydrochloric acid or seldom sodium hydroxide. This pH value
can vary depending on content of ore received.
Heavy Metal Stabilization:
In this stage, heavy metals such as arsenic and antimony are precipitated and stabilized using
ferric sulphate. Optimum pH 7.2 is automatically adjusted with hydrochloric acid or seldom
sodium hydroxide. This pH value can vary depending on content of ore received.
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