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This transition from open-pit to underground begins when open-pit mines are exhausted or inaccessible; meaning, they have either been depleted of minerals, rocks, and resources, or they are unfeasible to build upon. Once the decision is made to change from open-pit to underground mining, there are several approaches: miners can build spiral ...
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A major step in open pit mine planning and design is to define the ultimate expansion of the mine, often called the final or ultimate pit. When it comes to final pit selection there is usually more than one option to choose from. Most deposits support a range of sizes of pits that all are technically mineable and economically profitable.
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In open-pit coal mines, the haul units for overburden material are usually large, off-highway, end-dumping trucks; their capacities range from 35 to 250 tons. The stripping shovel has a large bucket, usually sits in the pit on the top of the coal seam, digs into the overburden material, and deposits it in the adjacent mined-out area. Draglines
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Before selecting the most suitable place for large volume of waste and low grade material, a series of studies must be carried out. ... Modern large-scale open pit mines move hundreds of thousands ...
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For miners, open-pit mining is safer than tunnel mining—but it's not exempt from risk. Mining tunnels can collapse or burn calamitously, killing many hundreds of miners at a time. For example, in 1942 a mixture of gas and coal dust exploded in the Honkeiko coal mine near Benxi in the … See more
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Open pit mining. This type of mining is used for near-surface deposits, primarily metal and nonmetal. The overburden is hauled away to a waste area and a large pit is excavated into the orebody. The depth of the pit is increased by removing material in successive benches. A few examples of commodities mined by this method would include iron and ...
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Open pit mines are used to exploit low grade, shallow ore bodies. However, some pits are quite deep – about 1 km. The mining rate is greater than 20,000 tonnes per day (tpd) but is usually much greater. Some pits operate at a rate of more than 100,000 tpd Open pit mining results in two waste streams: waste rock which contains no economic
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3.Stripping Ratios and Pit Limits The technical and economic decisions in open pit operations is determined primarily by the ratio of the volumes of stripping to the tonnage of ore mined as a whole and in various periods of the open pit activity. The quantitative estimation of these relationships is done by using the stripping ratio. The following …
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Meanwhile, open-pit mining poses environmental concerns due to WRD, which can lead to pollution and require extensive and costly closure and reclamation plans (Badakhshan et al., 2023;Samadi et al ...
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2 Classification of open-pit mining area 2.1 Open-pit mining area Open pit refers to the "open field" or "cavity" on the ground surface caused by mining activities, which is also called "mined-out zones". An open pit is a place with a complete production system for open-pit mining. A series
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In the surface mining of mineral deposits, land resources suitable for agricultural purposes are inappropriately spent in large volumes. When mining deep open pits, overburden rocks are mainly transported to the surface. The optimal solution for reducing the area of disturbed lands is the placement of overburden rocks in internal …
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The open pit mine production scheduling problem determines a sequence of three-dimensional, notional block extraction that maximises net present value (NPV) of future cash flows and satisfies technical and operational …
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Planning Considerations: The efficient transition from open pit mining to an underground operation requires extensive planning. For a large mining operation, planning could last as long as 20 years. The main factors and activities that need to be taken into account in the planning cycle are as follows: Definition of the ore body.
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Overview of open pit mining Deposits that are suitable for open pit mining are generally shallow and have a relatively uniform geology. Some deposits can be mined economically by only underground methods. Other deposits are best mined initially as open pits, with production switching to underground as deeper portions of the orebody are extracted.
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When compared to underground mining methods, open pit surface mining is considerably more efficient. 1. Increased Efficiency. One of the biggest benefits open pit mining produces is the growth in the overall efficiency when compared to deep-shaft mining methods. Mining occurs on the surface, so there aren't any space restrictions arising from ...
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Open pit mining is considered different from quarrying in the sense that it selectively extracts ore rather than an aggregate or a …
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The main coal seam of the Zhundong Open-pit Coal Mine is a huge inclined coal seam with a thickness of 70 m, and the tendency of the coal seam is to gradually decline from east to west.
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Of all the mine exploitation systems, block caving has the lowest cost, except for maybe open-pit mining or in-situ recovery. Cut-and-Fill Mining. A method of short-hole mining, cut-and-fill mining is used in irregular or …
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To avoid over-tailing and limit the risk of failure in open-pit mines, choosing an ideal and stable slope is critical. The major goal of this study was to provide a stable and optimal design for the ultimate slope of the Shadan Open Pit Mine using numerical modeling to calculate the minimum factor of safety equal to 1.20 under various situations of the …
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open-pit method, and if it proves to greater depths the open-pit mine will economically transfer to a suitable underground mining method. On the other hand, it is essential to exploit the ore ...
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Block caving mining method is one of the most viable and preferred mass underground mining methods for low grade orebody. However, in combined surface and underground mining, the breakthrough of an underground caving under an open pit may result in subsidence at the bottom of the pit. This can pose a serious threat for the …
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The optimization method for determining open pit limit is important, as it is crucial to achieve the most profitable outcome from the limited amount of reserves …
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Most open pit mines require the removal of overburden and waste material to access the orebody of interest. This activity is known as 'stripping'. So, in simple terms, the strip ratio ...
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Open-pit mines are becoming more intelligent and unmanned. One of the core technologies for autonomous driving is high-definition map technology, while refined mine maps are also needed to support scenarios such as vehicle–shovel collaboration, loading and unloading, production scheduling, and traffic safety control. To better serve …
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open-pit method, and if it proves to greater depths the open-pit mine will economically transfer to a suitable underground mining method. On the other hand, it is essential to exploit the ore ...
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Considerable savings in computation are achieved in the application of graph theoretic techniques to the open pit limit problem by selecting suitable tolerance parameters in the MSP algorithm. We ...
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The long-term planning of open pit mine is a dynamic process and should be reviewed periodically for enhancing the NPV and life of mine. Pit optimization through soft computing can be gainfully applied to resolve a number of important problems that arise in developing suitable planning strategies and management of a mine. Pit optimization ...
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Open-pit mining, or open-cast mining is a surface mining technique of extracting rock or minerals from the earth by their removal from an open pit or borrow. This form of mining …
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The optimization method for determining open pit limit is important, as it is crucial to achieve the most profitable outcome from the limited amount of reserves available. However, importance must be also given to geotechnical aspects to ensure that safety requirements are met. Thus, overall slope angle (OSAs) must be incorporated in the …
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Over 90% of the mining activities in developed countries adopt open pit methods [5].In large open pits, the orebody is usually found relatively close to the surface (thus ensuring overburden–to–ore ratios suitable for profitable mining operations) in sub-horizontal or slightly inclined deposits.
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