• Mining is extraction ore or minerals from
• There are two types of mining
2)Subsurface mining(i.e U/G mining)
What is surface mining?
• Surface mining is a method of mining used to
extract minerals and metals which are near
the surface of the Earth.
• There are three basic types of surface mining.
1) Open pit mining
What is Surface Miner?
It is continuously operating mobile opencast
It cuts consolidated soils and semi-solid rocks
with out drilling and blasting.
The cut material is pre-crushed and suitable
for belt conveying, loading and transporting.
Surface miner operates:
according to rock cutting technology.
the cutting drum is provided with point attack picks.
• Direct excavation of hard material without need
for drilling and blasting.
• High productivity.
• Low cost for multi seam mining including hard coal
• Higher recovery rate of coal.
• Possibility to link the machine directly to
continuous conveyor transport systems.
• Presently being used in Koyagudem OCP II of SCCL.
• Can work safely on a gradient of 1 in 10 ,however it
is only 1 in 4 gradient at KOCP II.
• Annual productivity of 2000 SM is around 2.00 MT
. It is different with other model of surface miners.
• Larger strike length of about 600m – 1000m and
widths of 300 m is suitable.
• At KOCP II wind rowing is done i.e. loading the
crushed coal by front and loader on to the trucks.
• Grade improved from F to E by this technology
What is Highwall Mining?
Highwall mining is a proven primary method
for mining coal from outcropping horizontal
It is a remotely controlled mining method.
In this method of mining, an unmanned
continuous miner is driven underground and
operated in front of the Highwall.
• When strip limits are reached by syrface
• When economic strip limits are reached.
• Transition from surface mining to U/G mining.
• Specific Highwall mining situations
-Open Cast Mining
Requirements of Highwall Mining
• Competent coal.
• Competent immediate over burden. If OB is
not competent, coal may be left as roof.
• Coal seams dipping from -12 to +5 degrees.
• Relative flat seams, no faults.
• Coal seams thicker than 80cm.
Safety: Web and Barrier Pillars
• Web pillars ensures support of OB.
• Barrier pillars prevents cascading collapse.
• Barrier pillar typically every 10 to 20 drives.
Penetration up to 300 m
Dip +5 to -12 degrees
Production is up to 120,000 t/ month.
70 to 80 % of coal recovery
Operates with a 4/5 man crew per shift
Low establish cost
Lower production cost than underground
Elevated cab with cameras
Above ground operation
Continuous monitoring of methane
High wall mining as a coal mining method:
Increases mine-able reserves
Mines coal cost effectively
With minimum risk