Read e-book Mine!!

Free download. Book file PDF easily for everyone and every device. You can download and read online Mine!! file PDF Book only if you are registered here. And also you can download or read online all Book PDF file that related with Mine!! book. Happy reading Mine!! Bookeveryone. Download file Free Book PDF Mine!! at Complete PDF Library. This Book have some digital formats such us :paperbook, ebook, kindle, epub, fb2 and another formats. Here is The CompletePDF Book Library. It's free to register here to get Book file PDF Mine!! Pocket Guide.
mine definition: 1. the one(s) belonging to or connected with me: 2. a hole or system of holes in the ground where. Learn more.
Table of contents

• Edgar Experimental Mine
• In this issue
• Navigation menu
• Emerald Hollow Mine LLC. Hiddenite, NC
• Most recent

This is when the mining company makes the decision whether to develop the mine or to walk away from the project. This includes mine planning to evaluate the economically recoverable portion of the deposit, the metallurgy and ore recoverability, marketability and payability of the ore concentrates, engineering concerns, milling and infrastructure costs, finance and equity requirements, and an analysis of the proposed mine from the initial excavation all the way through to reclamation.

The proportion of a deposit that is economically recoverable is dependent on the enrichment factor of the ore in the area. To gain access to the mineral deposit within an area it is often necessary to mine through or remove waste material which is not of immediate interest to the miner.

The total movement of ore and waste constitutes the mining process. Often more waste than ore is mined during the life of a mine, depending on the nature and location of the ore body. Waste removal and placement is a major cost to the mining operator, so a detailed characterization of the waste material forms an essential part of the geological exploration program for a mining operation. Once the analysis determines a given ore body is worth recovering, development begins to create access to the ore body.

The mine buildings and processing plants are built, and any necessary equipment is obtained. The operation of the mine to recover the ore begins and continues as long as the company operating the mine finds it economical to do so. Once all the ore that the mine can produce profitably is recovered, reclamation begins to make the land used by the mine suitable for future use.

Mining techniques can be divided into two common excavation types: surface mining and sub-surface underground mining. Targets are divided into two general categories of materials: placer deposits , consisting of valuable minerals contained within river gravels, beach sands, and other unconsolidated materials ; and lode deposits , where valuable minerals are found in veins, in layers, or in mineral grains generally distributed throughout a mass of actual rock. Both types of ore deposit, placer or lode, are mined by both surface and underground methods. Some mining, including much of the rare earth elements and uranium mining , is done by less-common methods, such as in-situ leaching : this technique involves digging neither at the surface nor underground.

The extraction of target minerals by this technique requires that they be soluble, e.

Some minerals, such as copper minerals and uranium oxide , require acid or carbonate solutions to dissolve. Surface mining is done by removing stripping surface vegetation, dirt, and, if necessary, layers of bedrock in order to reach buried ore deposits. Most but not all placer deposits, because of their shallowly buried nature, are mined by surface methods.

Finally, landfill mining involves sites where landfills are excavated and processed. High wall mining is another form of surface mining that evolved from auger mining. In high wall mining, the coal seam is penetrated by a continuous miner propelled by a hydraulic Push-beam Transfer Mechanism PTM. A typical cycle includes sumping launch-pushing forward and shearing raising and lowering the cutter-head boom to cut the entire height of the coal seam.

As the coal recovery cycle continues, the cutter-head is progressively launched into the coal seam for The Push-beam system can penetrate nearly 1, feet m into the coal seam. One patented high wall mining system uses augers enclosed inside the Push-beam that prevent the mined coal from being contaminated by rock debris during the conveyance process. Sub-surface mining consists of digging tunnels or shafts into the earth to reach buried ore deposits.

Ore, for processing, and waste rock, for disposal, are brought to the surface through the tunnels and shafts. Sub-surface mining can be classified by the type of access shafts used, and the extraction method or the technique used to reach the mineral deposit.

In this issue

Drift mining utilizes horizontal access tunnels, slope mining uses diagonally sloping access shafts, and shaft mining utilizes vertical access shafts. Mining in hard and soft rock formations require different techniques. Other methods include shrinkage stope mining , which is mining upward, creating a sloping underground room, long wall mining , which is grinding a long ore surface underground, and room and pillar mining, which is removing ore from rooms while leaving pillars in place to support the roof of the room.

Room and pillar mining often leads to retreat mining , in which supporting pillars are removed as miners retreat, allowing the room to cave in, thereby loosening more ore. Additional sub-surface mining methods include hard rock mining , which is mining of hard rock igneous, metamorphic or sedimentary materials, bore hole mining, drift and fill mining, long hole slope mining, sub level caving, and block caving. Heavy machinery is used in mining to explore and develop sites, to remove and stockpile overburden, to break and remove rocks of various hardness and toughness, to process the ore, and to carry out reclamation projects after the mine is closed.

Bulldozers, drills, explosives and trucks are all necessary for excavating the land. In the case of placer mining , unconsolidated gravel, or alluvium , is fed into machinery consisting of a hopper and a shaking screen or trommel which frees the desired minerals from the waste gravel. The minerals are then concentrated using sluices or jigs. Large drills are used to sink shafts, excavate stopes, and obtain samples for analysis. Trams are used to transport miners, minerals and waste.

Lifts carry miners into and out of mines, and move rock and ore out, and machinery in and out, of underground mines. Huge trucks, shovels and cranes are employed in surface mining to move large quantities of overburden and ore. Processing plants utilize large crushers, mills, reactors, roasters and other equipment to consolidate the mineral-rich material and extract the desired compounds and metals from the ore. Once the mineral is extracted, it is often then processed.

The science of extractive metallurgy is a specialized area in the science of metallurgy that studies the extraction of valuable metals from their ores, especially through chemical or mechanical means.

Navigation menu

Mineral processing or mineral dressing is a specialized area in the science of metallurgy that studies the mechanical means of crushing, grinding, and washing that enable the separation extractive metallurgy of valuable metals or minerals from their gangue waste material. Processing of placer ore material consists of gravity-dependent methods of separation, such as sluice boxes. Only minor shaking or washing may be necessary to disaggregate unclump the sands or gravels before processing.

Processing of ore from a lode mine, whether it is a surface or subsurface mine, requires that the rock ore be crushed and pulverized before extraction of the valuable minerals begins. After lode ore is crushed, recovery of the valuable minerals is done by one, or a combination of several, mechanical and chemical techniques. Since most metals are present in ores as oxides or sulfides, the metal needs to be reduced to its metallic form.

This can be accomplished through chemical means such as smelting or through electrolytic reduction, as in the case of aluminium. Geometallurgy combines the geologic sciences with extractive metallurgy and mining. In , led by Chemistry and Biochemistry professor Bradley D. Smith, University of Notre Dame researchers "invented a new class of molecules whose shape and size enable them to capture and contain precious metal ions," reported in a study published by the Journal of the American Chemical Society. The new method "converts gold-containing ore into chloroauric acid and extracts it using an industrial solvent.

The container molecules are able to selectively separate the gold from the solvent without the use of water stripping. Environmental issues can include erosion , formation of sinkholes , loss of biodiversity , and contamination of soil , groundwater and surface water by chemicals from mining processes. In some cases, additional forest logging is done in the vicinity of mines to create space for the storage of the created debris and soil. Mining companies in most countries are required to follow stringent environmental and rehabilitation codes in order to minimize environmental impact and avoid impacting human health.

These codes and regulations all require the common steps of environmental impact assessment , development of environmental management plans, mine closure planning which must be done before the start of mining operations , and environmental monitoring during operation and after closure.

However, in some areas, particularly in the developing world, government regulations may not be well enforced. For major mining companies and any company seeking international financing, there are a number of other mechanisms to enforce environmental standards. These generally relate to financing standards such as the Equator Principles , IFC environmental standards, and criteria for Socially responsible investing.

Mining companies have used this oversight from the financial sector to argue for some level of industry self-regulation. This was followed by the Global Mining Initiative which was begun by nine of the largest metals and mining companies and which led to the formation of the International Council on Mining and Metals , whose purpose was to "act as a catalyst" in an effort to improve social and environmental performance in the mining and metals industry internationally. For example, ISO and ISO , which certify an "auditable environmental management system", involve short inspections, although they have been accused of lacking rigor.

Miscellaneous other certification programs exist for various projects, typically through nonprofit groups.

• It Happened at the Gym (Elizabeths Tale Book 6)?
• Principia Paranoia?
• Tumenye Ingagi (Kinyarwanda).
• Jerry Goldsmith Music Scoring for American Movies (I libri saggi).
• Zoës Boutique: A Modern Stage Play (Act I Book 1)?
• 4 of 5: LOOK PAPA! NO MORE CHOKEHOLD!: I AM Now Free to Build Your Kingdom Here on Earth! (Kingdom Displaces Church (Which Tried to Replace Kingdom)).

The purpose of a EPS PEAKS paper [45] was to provide evidence on policies managing ecological costs and maximise socio-economic benefits of mining using host country regulatory initiatives. It found existing literature suggesting donors encourage developing countries to:. Ore mills generate large amounts of waste, called tailings.

For example, 99 tons of waste are generated per ton of copper, with even higher ratios in gold mining — because only 5. These tailings can be toxic. Tailings, which are usually produced as a slurry , are most commonly dumped into ponds made from naturally existing valleys.

The waste is classified as either sterile or mineralised, with acid generating potential, and the movement and storage of this material forms a major part of the mine planning process.