What is mining?
“Mining is the process of excavating minerals of economic value from the earth’s crust for benefit of mankind”. What is mining There are various types of ore recovered by mining including metals, coal, limestone, bauxite, etc. Mining is the mother industry for other industries.
Mine development and IMPORTANCE OF MINING:
Mining is an important profession because all most products used in modern homes require heavy minerals in some form or other. Mining is a money-making business. Not only do mining companies prosper, but governments also make money from revenues. Workers also receive income and benefits.
The process of constructing a mining facility and the infrastructure to support the facility is known as mine development. The term is employed to designate the operations involved in preparing a mine for ore extraction.
There is some terminology that can use in mining studies.
Sinking- It’s Actually Shaft sinking
Tunneling/Adit- Access to develop ways & infrastructures
Drifting & ramping- Connecting passage of one or more levels
Raising- A raise is a vertical or steeply-inclined opening, that serves as a ladder way access to stopes, as an ore pass, or as an airway in the mine’s ventilation system.
Mine development STAGES IN THE LIFE OF A MINE;
1. Prospecting:1-3 Years
Search for ore a. Prospecting methods Direct: Physical, geological Indirect: Geophysical, geochemical b. Locate favorable loci (maps, literature, old mines) c. Air: Aerial photography, airborne geophysics, satellite d. Surface: Ground geophysics, geology e. Spot anomaly, analyze, evaluation.
2. Exploration: 2-5 Years
Defining the extent and value of ore (examination/ evaluation) a. Sample (drilling or excavation) b. Estimate tonnage and grade c. Valuate deposit: Present value = Income – Cost Feasibility study: make the decision to abandon or develop.
3. Mine Development: 2-5 Years
Opening up ore deposit for production a. Acquire mining rights (purchase or lease), if not done in stage 2 b. File environmental impact statement, technology assessment, permit c. Construct access roads, and transport system d. Locate surface plant, construct facilities e. Excavate deposit (strip or sink shaft).
4. Mine development in Exploration: 10-30 Years
Large-scale production of ore a. Factors to be considered: Geologic, geographic, economic, environmental, societal safety b. Types of mining methods Surface: Open pit, open cast, etc. Underground: Room and pillar, Cut & fill, Longwall, block caving c. Monitor costs and economic payback.
5. Reclamation: 1-10 Years
Restoration of site
a. Removal of plants and buildings
b. Reclamation of waste and tailings dumps
c. Monitoring of discharges
Mine Development and Operation:
Mine operations are the process of managing many immediate and long-term activities in and around a mine site in order to facilitate the production of a mineral product.
A mine operation has five main activities:
1. Excavation of earth and rock
2. Processing and separating the ore from waste rock
3. Storage and maintenance of waste material
4. Environmental monitoring – air & water quality and noise levels
5. Operation of supporting services – repair shops, labs, living quarters, warehouses, and offices.
Mine Development Process and Methods:
Mining techniques can be divided into two common excavation types-Surface/Open-pit/Opencast mining method.
Surface mining is much more common, and produces, for example, 85% of minerals (excluding petroleum and natural gas) in the United States, including 98% of metallic ores. Sub-surface/Underground mining method in Bangladesh we have only underground/subsurface mining.
Some common surface mining methods are Open-pit: Reclamation after completion Open-cast: Reclamation during mining Quarries: Stone, crushed rock, sand, and gravel Strip Mining: Removing surface (Overburden rock) in strips up to the resources.
Underground mining methods: There are different techniques/methods of underground mining methods and the choice is closely related to the Geology of the deposit and the degree of ground support necessary to make the method productive and safe.
Methods based on the extent of support utilized.
Unsupported Mining Methods;
Caving Mining Methods;