Question: What are the disadvantages of open pit mining? And what are common open pit mining equipment?
Answer: Open pit mining, also called open-pit mining, open-cut mining, is a method of extracting rock or minerals from the earth by their removal from an open pit or borrow. Openpit mines are used when deposits of commercially useful minerals or rock are found near the surface. Typically, open-pit mines that produce building materials and dimension stone are commonly referred to as quarries. In the mining industry, coal, iron ore, and phosphates are often extracted by openpit mining. Often the mineral deposit is covered by soil, which must first be stripped off, usually by large machines such as walking draglines and bucket-wheel excavators. The ore deposit is then broken up by explosives. Of course, openpit mining has its own disadvantages. Especially, open-pit mines are typically enlarged until either the mineral resource is exhausted, or an increasing ratio of overburden to ore makes further mining uneconomic. When this occurs, the exhausted mines are sometimes converted to landfills for disposal of solid wastes. For mining investors, they should pay much attention to these disadvantages mentioned above.
As for common openpit mining equipment, it has varied types. For example, a haul road is usually situated at the side of the pit, forming a ramp up which trucks can drive, carrying ore and waste rock. Mining trucks, crushing machines, grinding mills, conveying systems, feeding machines are common types of openpit mining equipment.