what is mineral leaching
HER WE STUDIED ABOUT MINING AND ITS DIFFERENT TYPES
Buen tema para tener en cuenta en los procesos mineros
Los minerales que constituyen la corteza terrestre se han formado a partir de los elementos químicos que originaron el planeta, gracias a reacciones ocurridas en su interior. Por este motivo, la cantidad de combinaciones es inmensa.
los minerales se encuentran en pocas áreas debido a las circunstancias que se necesitan, para hallarlos se requiere de conocimiento y experiencia, hay factores que permiten analizar antes de explotar los minerales, hay varias técnicas de extracción, hay minería de superficie y de sub superficie. también esta la hidráulica. un claro ejemplo de minería y alteraciones económicos es el cobre que en el siglo pasado representó una repentina subida y lo hizo muy rentable. lo malo es que en la minería se utiliza mucha agua y esto es perjudicial para el medio ambiente, también deben desplazarse grandes cantidades de tierra y esto afecta a los ecosistemas terrestres.
Is deep mining expensive?
What are the different types of mining?
Minerals are not evenly distributed in the earth's crust. Mineral ores are found in just a relatively few areas, because it takes a special set of circumstances to create them. Therefore, the signs of a mineral deposit are often small and difficult to recognize. Locating deposits requires experience and knowledge. Geologists can search for years before finding an economic mineral deposit.
Deposit size, its mineral content, extracting efficiency, processing costs and market value of the processed minerals are all factors that determine if a mineral deposit can be profitably developed. For example, when the market price of copper increased significantly in the 1970s, some marginal or low-grade copper deposits suddenly became profitable ore bodies.
After a potentially profitable mineral deposit is located, it is mined by one of several techniques. Which technique is used depends upon the type of deposit and whether the deposit is shallow and thus suitable for surface mining or deep and thus requiring sub-surface mining.
Surface mining techniques include:
• Open-pit mining
• Area strip mining
• Contour strip mining
• Hydraulic mining
Sub-surface mining techniques include:
• Traditional sub-surface mining
• In-situ mining
Surface mining techniques include: open-pit mining, area strip mining, contour strip mining and hydraulic mining.
Open-pit mining involves digging a large, terraced hole in the ground in order to remove a near-surface ore body. This technique is used in copper ore mines in Arizona and Utah and iron ore mines in Minnesota.
Area strip mining is used in relatively flat areas. The overburden of soil and rock is removed from a large trench in order to expose the ore body. After the minerals are removed, the old trench is filled and a new trench is dug. This process is repeated until the available ore is exhausted.
Hydraulic mining is used in places such as the Amazon in order to extract gold from hillsides. Powerful, high-pressure streams of water are used to blast away soil and rock containing gold, which is then separated from the runoff. This process is very damaging to the environment, as entire hills are eroded away and streams become clogged with sediment. If land subjected to any of these surface mining techniques is not properly restored after its use, then it leaves an unsightly scar on the land and is highly susceptible to erosion.
Contour strip mining is a similar technique except that it is used on hilly or mountainous terrains. A series of terraces are cut into the side of a slope, with the overburden from each new terrace being dumped into the old one below.
Some mineral deposits are too deep to be surface mined and therefore require a sub-surface mining
In the traditional sub-surface method a deep vertical shaft is dug and tunnels are dug horizontally outward from the shaft into the ore body. The ore is removed and transported to the surface. The deepest such sub-surface mines (deeper than 3500m) in the world are located in the Witwatersrand basin of South Africa, where gold is mined. This type of mining is less disturbing to the land surface than surface mining. It also usually produces fewer waste materials. However, it is more expensive and more dangerous than surface mining methods.
A newer form of subsurface mining known as in-situ mining is designed to co-exist with other land uses, such as agriculture. An in-situ mine typically consists of a series of injection wells and recovery wells built with acid-resistant concrete and polyvinyl chloride casing.
A weak acid solution is pumped into the ore body in order to dissolve the minerals. Then, the metal-rich solution is drawn up through the recovery wells for processing at a refining facility. This method is used for the in-situ mining of copper ore.