MiningMining• A process that is use to excavate the

minerals deposited in earth.

Types of mining methodTypes of mining method

There are two main type of mining method

1. Underground mining2. Surface mining

Mining

Underground mining Surface mining

Open pit mining Strip MiningRoom and Pillar mining Long wall mining

Mountain top mining

Classification of mining method

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.

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

matter

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.

Open pit miningOpen pit mining

• Open pit can be done by two way.1. Manual mining2. Mechanized mining

MachineryMachinery

• Scrapers• Bulldozers• Front-end Loaders• Rotary drill • Shovel• Dragline

• Bucket-wheel excavator

• Trucks• Dumpers• Conveyor• Bulldozer

Production procedureProduction procedure

• Site preparation• Drilling and blasting• Removal of overburden• Excavation, loading and transporting• Reclamation

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.

DRILLING AND BLASTINGDRILLING AND BLASTING

• When the overburden is hard, it is blasted before deployment of excavator for its loading out.

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.

Excavation,Excavation,Loading and TransportLoading and Transport

• In mechanized mines the coal is loaded In mechanized mines the coal is loaded by loading shovels, Hydraulic excavator or by loading shovels, Hydraulic excavator or wheel loaders into trucks for out bye wheel loaders into trucks for out bye transport.transport.

ReclamationReclamation

• Backfilling• Regrading• Surface stabilizing• Revagitation• Restoration

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

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