Molybdenum, Mo, is a transition metal element, found in
Group VIa of the periodic table.
Atomic Number : 42
Relative Atomic Mass : 95.94
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Discovery
Molybdenum was discovered by K W Scheele in 1778AD.
Molybdenum was isolated by P J Hjelm in 1790AD.
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Occurrence
Molybdenum can be found as
molybdenite, MoS2,
wulfenite, PbMoO4, and
molybdite, MoO3.
Bottom
Endako is Canada's largest capacity molybdenum mine and the only one producing molybdenum as it's primary product. Molybdenum is used for
a variety of purposes, as this table indicates.
USES OF MOLYBDENUM
ALLOY STEEL 45%
STAINLESS STEEL 22%
TOOL STEEL 8%
CHEMICALS AND LUBRICANTS 10%
CAST IRON AND STEEL MILL ROLLS 6%
SPECIAL AND SUPER ALLOYS 3%
MOLYMETAL 4%
MISCELLANEOUS 2%
Many steps are involved in preparing molybdenum for commercial use:
The Endako ore deposit is mined in three separate pits: the Endako Pit,
the Denak East Pit, and the Denak West Pit. The pits are designed from exploration
information using computer technology. Production planning also relies heavily on computers
to optimize the mining process. The size of the main Endako Pit is approximately 2,000
metres in length and 700 metres in width. Wall heights are up to 350 metres
on the North Wall.
The Endako Pit is mined in 13.4 m benches or levels. Three electric rotary
drills are used to sink 32 cm holes 16 m deep. Drill cuttings are assayed and
used for grade control. Under normal conditions, the holes are loaded with a
blasting agent containing a mixture of ammonium nitrate and fuel oil (ANFO).
Special emulsions are used in exceptionally wet conditions. Ore and waste
boundaries are marked on the blasted rock with colored stakes.
The broken ore and waste rock is loaded onto haulage trucks by four
electric shovels, the largest of which loads 60 tonnes with each pass of the bucket.
Nine haulage trucks of 172 tonnes capacity carry ore to the crusher and waste
to the dumps.
Milling can be broken down into seven basic operations: primary and secondary
crushing, grinding, flotation, leaching, roasting, packaging and tailings
disposal.
The ore trucks dump an average of 1200 tonnes of ore per hour into the
primary crusher. The ore is then screened and the undersize material goes directly
to the fine ore bins. Oversize material is conveyed to the coarse ore stockpile
and then on to the secondary crusher.
Crushed ore is ground finer in the rod mills and ball mills along with the addition
of water and reagants.
The molybdenum is recovered through flotation. The molybdenum concentrate
is acid leached, roasted and packed for shipment to customers.
The tailings are pumped to disposal ponds where it is impounded behind dams.
Water is reclaimed from these ponds and pumped back to the mill where is it mixed
with fresh water from Francois Lake, 3.5 km away. The nominal daily mill
input is 28,000 tonnes of ore per day. This yields about 16,200 kg of molybdenum
sulphide (MoS2), the majority of which is converted to molybdic oxide (MoO3)
before going to the market. Some of the molybdenum sulphide is further refined in our
MolyLube plant, then treated to produce a number of specialty products for various industrial
customers. Endako produces UltraPure which is used as an oil additive and lubricant.
