Up to now we have had industry spotlights covering bulk material handling, pulp and paper, and power generation; today we are going to look at mining, a profession that predates history itself.
What is mining?
Mining can be defined as the extraction of valuable minerals or other geological materials from the Earth, usually from an ore body, lode, vein seam, reef, or placer deposit. Metals, coal, oil shale, gemstones, limestone, chalk, rock salt, gravel, and clay – to name a few – are all recovered through this extraction process. In a wider sense, it can include the extraction of any non-renewable resource such as petroleum, natural gas, or even water. A rule of thumb is that if you cannot grow it through agricultural processes or artificially in a laboratory or factory, then you will need to turn to mining.
Mining throughout and before history
As alluded to earlier, evidence of mining practices has been found from some of the oldest civilizations of Man – starting with stones and ceramics followed later by metals that were available near the surface of the earth. These practices have been observed in Ancient Egypt, ancient Greece and Rome, and Medieval Europe – none of which compare to the oldest-known mine found in Eswatini which has been radiocarbon dated to about 43,000 years old.
Types of mining
There are two common types of excavation: surface mining and sub-surface mining.
Surface mining, the most common form of mining today, is done by removing (stripping) surface vegetation, dirt, and, if necessary, layers of bedrock to reach buried ore deposits. Techniques for surface mining include:
- Open-pit mining
- Strip mining
- Mountain top removal (commonly associated with the mining of coal)
- And landfill mining
Sub-surface mining consists of digging tunnels or shafts into the earth to reach buried ore deposits. It can be broken into classifications based on the access shafts and extraction methods that are employed. A few of the categories of sub-surface mining include:
- Drift mining
- Slope mining
- Shaft mining
- And shrinkage stope mining
There are many heavy-duty machines used in mining. Bulldozers, drills, trucks, excavation stopes, sink shafts, trams, and lifts to name a few. This is where we get involved with the mining industry at Hammer Haag Steel. Over the years we have produced countless massive steel components for use in this industry.
The resources produced by the mining industry and the products that occur downstream are inextricably woven into the fabricate of our modern societies. To secure the future of mining, leaders in the industry, in concert with government oversight, are always trying to make the practice of mining safer and to reduce the environmental footprint it can have on the earth.