Mining Technology and Methods

Study Notes

Mining is the process of extracting minerals from a rock seam or ore, a natural rock or sediment containing one or more valuable minerals.
Modern mining technology uses geophysical techniques, including measuring magnetic, gravity, and sonic responses of rocks above and around a prospective mineral ore body.
There are two main methods of mining: Surface Mining and Underground Mining.

Surface Mining is used to extract ore minerals near the surface of the earth.
The soil and rocks covering the ores are removed through blasting, a controlled use of explosives and gas exposure to break rocks.
Types of Surface Mining include:
- Open-pit mining: the most common type of surface mining, where a big hole (or pit) is created in the ground through blasting and drilling.
- Strip mining: the removal of a thin strip of overburden (earth or soil).
- Dredging: the process of mining materials from the bottom of a body of water, including rivers, lakes, and oceans.

Mineral processing is the process of extracting minerals from ore, refining them, and preparing them for use.
Stages of Mineral Processing:
- Sampling: removing a portion for the analysis of the material.
- Analysis: evaluating the valuable component in an ore.
- Comminution: separating the valuable components of the ore through crushing and grinding.
- Concentration: separating the valuable minerals from the raw materials.
- Dewatering: using concentration to convert the minerals to a usable form through filtration and sedimentation of the suspension and drying of the solid materials.

Fossil fuels provide almost 90% of the world's energy supply.
Fossil fuels are non-renewable resources, formed from the remains of dead plants and animals, and have a finite source.

There are three main types of fossil fuels:
- Coal: an important and primary fossil fuel, formed from buried and compressed plants and marshes millions of years ago.
- Oil: formed from algae and other organic materials buried in mud at the bottom of the sea and lakes.
- Natural Gas: formed from the remains of dead plants and animals.

There are four major ranks of coal:
- Anthracite: the highest rank of coal, hard, brittle, and black, with a high percentage of fixed carbon and low percentage of volatile matter.
- Bituminous coal: has a high heating value and is the most common type of coal used in electricity generation.
- Subbituminous coal: has a higher heating value than lignite and is black and dull in appearance.
- Lignite (brown coal): the lowest grade coal with the least concentration of carbon.