Coal mining

1. MiningMining
• A process that is use to excavate the
minerals deposited in earth.

2. Types of mining methodTypes of mining method
There are two main type of mining method
1. Underground mining
2. Surface mining

3. Mining
Underground mining Surface mining
Open pit mining Strip MiningRoom and Pillar mining Long wall mining
Mountain top mining
Classification of mining method

4. Open pit mining
• Open pit mining is the process of mining a
near surface deposit by means of a
surface pit excavated using horizontal
benches.

5. The shape of the excavation or mine vary
depending upon the size and shape mineral
matter

7. WHEN TO ADOPT OPEN-PIT
MINING
• The deposit should not deeper than 90m i.e.
The limiting depth of open pit is 90m to
300m.
• The ratio of overburden to coal should be
less. A ratio of 4:1 is considered desirable
but in some cases 6:1 is also considered
economic.
• The coal seem should be uniform thickness
and preferably flat.
• There should not be excessive make of
water.
• A mild climatic condition should be favored.

8. Open pit miningOpen pit mining
• Open pit can be done by two way.
1. Manual mining
2. Mechanized mining

9. MachineryMachinery
• Scrapers
• Bulldozers
• Front-end Loaders
• Rotary drill
• Shovel
• Dragline
• Bucket-wheel
excavator
• Trucks
• Dumpers
• Conveyor
• Bulldozer

10. Production procedureProduction procedure
• Site preparation
• Drilling and blasting
• Removal of overburden
• Excavation, loading and transporting
• Reclamation

11. Site PreparationSite Preparation
• The process consist of felling and removal
of trees. Removal of Top soil and subsoil
and their storage for reuse in Reclamation
phase, after the mining operations are
over.

12. DRILLING AND BLASTINGDRILLING AND BLASTING
• When the overburden is hard, it is
blasted before deployment of excavator
for its loading out.

13. Removal of overburdenRemoval of overburden
• The overburden is removed by Dragline,
Shovel and Dumper.
• Loading into conveyors, the conveyors
may be laid out around the pit or across
the pit so that the waste can be reuse in
reclamation.

14. Excavation,Excavation,
Loading and TransportLoading and Transport
• In mechanized mines the coal is loadedIn mechanized mines the coal is loaded
by loading shovels, Hydraulic excavator orby loading shovels, Hydraulic excavator or
wheel loaders into trucks for out byewheel loaders into trucks for out bye
transport.transport.

15. ReclamationReclamation
• Backfilling
• Regrading
• Surface stabilizing
• Revagitation
• Restoration

17. AdvantagesAdvantages
• High productivity
• Low capital cost
• Lower the operating cost
• Shorten the gestation period
• Greater geological certainty
• Greater safety and better working
condition for mining personnel's
• Simplify engineering, planning and control

18. DisadvantagesDisadvantages
• Adverse effect on ecology and environment.
Problem of noise and vibration consequence to
heavy blast
• Agriculture land is damage
• High reclamation cost
• Danger of inrush of water from aquifer
zone
• Handling of high unproductive material
• Exposure to adverse climatic condition