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Operations are described at a number of mines in Namibia. The Okorusu open-cast mine is one of the world’s lowest-cost acid-grade fluorspar producers and has a capacity of 120 000 tpa of concentrate. Following drilling and blasting, ore and waste rock are excavated from the bottom of the pit and hauled to the primary jaw crusher. The ore is screened, further crushed using secondary and tertiary cone crushers and separated into three stockpiles according to grade and impurities. Ore from the stockpiles is blended to a feed averaging 35% CaF2 and milled before flotation. A 97% pure concentrate is produced which is filtered to reduce the water content. The Langer Heinrich U mine has proven and probable reserves of 110 000 000 t at 0.055% U3O8. After blasting the run of mine ore is transported through grade-control scanners, stockpiled and then blended to about 800 ppm U to provide a uniform feed to the mill. Processing involves screening, solid-liquid separation, passing though heat exchangers and further heating by direct steam injection in alkaline leach tanks. The pregnant leach solution is converted to concentrate using an ion exchange process and then subjected to precipitation, centrifuging and drying to produce yellowcake. The Navachab open-pit mined produced 86 264 oz of Au in 2010, a 32% increase compared with 2009. Feed material is reduced to 150 mm using a primary jaw crusher and fed to s semiautogenous grinding mill which uses hydrocyclones to produce material averaging 75% at 75 micrometres. Processing is through a conventional carbon in pulp plant and Au is recovered using activated carbon, elution and electrowinning. The Lofdal project has the potential for the discovery of multiple rare earth element occurrences and is focusing on heavy rare earth-enriched carbonatite deposits., Operations are described at a number of mines in Namibia. The Okorusu open-cast mine is one of the world’s lowest-cost acid-grade fluorspar producers and has a capacity of 120 000 tpa of concentrate. Following drilling and blasting, ore and waste rock are excavated from the bottom of the pit and hauled to the primary jaw crusher. The ore is screened, further crushed using secondary and tertiary cone crushers and separated into three stockpiles according to grade and impurities. Ore from the stockpiles is blended to a feed averaging 35% CaF2 and milled before flotation. A 97% pure concentrate is produced which is filtered to reduce the water content. The Langer Heinrich U mine has proven and probable reserves of 110 000 000 t at 0.055% U3O8. After blasting the run of mine ore is transported through grade-control scanners, stockpiled and then blended to about 800 ppm U to provide a uniform feed to the mill. Processing involves screening, solid-liquid separation, passing though heat exchangers and further heating by direct steam injection in alkaline leach tanks. The pregnant leach solution is converted to concentrate using an ion exchange process and then subjected to precipitation, centrifuging and drying to produce yellowcake. The Navachab open-pit mined produced 86 264 oz of Au in 2010, a 32% increase compared with 2009. Feed material is reduced to 150 mm using a primary jaw crusher and fed to s semiautogenous grinding mill which uses hydrocyclones to produce material averaging 75% at 75 micrometres. Processing is through a conventional carbon in pulp plant and Au is recovered using activated carbon, elution and electrowinning. The Lofdal project has the potential for the discovery of multiple rare earth element occurrences and is focusing on heavy rare earth-enriched carbonatite deposits.

Uralkali operates five mines and seven ore treatment mills at Berezniki and Solikamsk in the Perm region of Russia and has a world potash market share of about 20%. The main products are standard and granular muriate of potash (MOP). Pink MOP is produced by flotation based on the varying flotability of sylvite and halite in saturated aqueous solution of KCl and NaCl, and a chemical treatment known as halurgic is used to produce white MOP based on differences in the joint solubility of KCl and NaCl in water at different temperatures. KCl crystallises out of the saturated solution as it cools to produce potash fertilisers containing 95%-98% MOP. The process for granular potash is the same as for pink MOP up to the drying stage, after which the potash powder is compressed into flakes and granules of the correct size are selected. Expansion projects include replacement of hoist machines at Berezniki-4 to increase production of potash ore and the launch of a new production line, a de-bottlenecking project and increased efficiency at the Berezniki-2, Berezniki-3, Solikamsk-2 and Solikamsk-3 operations, expansion of the Solikamsk mine and construction of new mines at Ust-Yayvinsky and Polovodovsky, each with production of 11 000 000 tpa of ore., Uralkali operates five mines and seven ore treatment mills at Berezniki and Solikamsk in the Perm region of Russia and has a world potash market share of about 20%. The main products are standard and granular muriate of potash (MOP). Pink MOP is produced by flotation based on the varying flotability of sylvite and halite in saturated aqueous solution of KCl and NaCl, and a chemical treatment known as halurgic is used to produce white MOP based on differences in the joint solubility of KCl and NaCl in water at different temperatures. KCl crystallises out of the saturated solution as it cools to produce potash fertilisers containing 95%-98% MOP. The process for granular potash is the same as for pink MOP up to the drying stage, after which the potash powder is compressed into flakes and granules of the correct size are selected. Expansion projects include replacement of hoist machines at Berezniki-4 to increase production of potash ore and the launch of a new production line, a de-bottlenecking project and increased efficiency at the Berezniki-2, Berezniki-3, Solikamsk-2 and Solikamsk-3 operations, expansion of the Solikamsk mine and construction of new mines at Ust-Yayvinsky and Polovodovsky, each with production of 11 000 000 tpa of ore.

Developments are reviewed in semi and fully mobile in-pit crushing and conveying systems. The technology is being increasingly considered during mine planning against the background of increasing fuel costs, potential truck and tyre shortages, CO2 emissions, lower ore grades and deepening open-pit mines. Systems may be based on a gyratory, double-roll, roll- sizer and in some cases a jaw crusher and typically use belt wagon/conveyor bridges, transfer conveyors, fixed overland conveyors, extendable conveyors and moveable conveyors to carry coal or ore to a process plant or to a spreader for waste rock applications. The market is mainly for greenfield operations in Australia, China, USA and South America, and there is also significant interest from Russian coalfields. Details are given of equipment suppliers and consulting companies., Developments are reviewed in semi and fully mobile in-pit crushing and conveying systems. The technology is being increasingly considered during mine planning against the background of increasing fuel costs, potential truck and tyre shortages, CO2 emissions, lower ore grades and deepening open-pit mines. Systems may be based on a gyratory, double-roll, roll- sizer and in some cases a jaw crusher and typically use belt wagon/conveyor bridges, transfer conveyors, fixed overland conveyors, extendable conveyors and moveable conveyors to carry coal or ore to a process plant or to a spreader for waste rock applications. The market is mainly for greenfield operations in Australia, China, USA and South America, and there is also significant interest from Russian coalfields. Details are given of equipment suppliers and consulting companies.

The market for contract mining is reviewed and reasons for the selection of contractors by mining companies are discussed. The value of Australian contract mining work is expected to increase due to iron ore developments in Western Australia and further investment in coal projects resulting from demand from China. On a global scale most mines employ contractors for tasks including construction, development, stoping and specialised services such as raise boring and grouting plants. Production contract mining has been popular for many years in Australia and South Africa but is less common in the Americas. The services and equipment provided by contract mining companies are reviewed including Banlaw Africa Group, Barminco (Australia), Cementation Canada, Cominvi (Mexico), KMC Mining, which is primarily focused on the Canadian oil sands sector, Ledcor CMI (British Columbia) and Murray and Roberts Cementation (South Africa)., The market for contract mining is reviewed and reasons for the selection of contractors by mining companies are discussed. The value of Australian contract mining work is expected to increase due to iron ore developments in Western Australia and further investment in coal projects resulting from demand from China. On a global scale most mines employ contractors for tasks including construction, development, stoping and specialised services such as raise boring and grouting plants. Production contract mining has been popular for many years in Australia and South Africa but is less common in the Americas. The services and equipment provided by contract mining companies are reviewed including Banlaw Africa Group, Barminco (Australia), Cementation Canada, Cominvi (Mexico), KMC Mining, which is primarily focused on the Canadian oil sands sector, Ledcor CMI (British Columbia) and Murray and Roberts Cementation (South Africa).

Communication and tracking systems for underground mining operations are discussed. Tracking systems provide identification information for all employees which is displayed on computer servers at the surface. Voice-over Internet protocol handsets and two-way text message devices allow rescue workers or mine personnel at the surface to send messages to underground miners and to receive text responses. Radio frequency identification and Wi-Fi tags attached to items of clothing or installed in cap lamps, and mobile phones linked with two-way voice, video and data exchange systems enable surface operators to track miners and to stay in contact. Tracking and communication systems are often combined to create integrated networks using technologies such as Ethernet and leaky feeder systems. The systems available and equipment suppliers are reviewed., Communication and tracking systems for underground mining operations are discussed. Tracking systems provide identification information for all employees which is displayed on computer servers at the surface. Voice-over Internet protocol handsets and two-way text message devices allow rescue workers or mine personnel at the surface to send messages to underground miners and to receive text responses. Radio frequency identification and Wi-Fi tags attached to items of clothing or installed in cap lamps, and mobile phones linked with two-way voice, video and data exchange systems enable surface operators to track miners and to stay in contact. Tracking and communication systems are often combined to create integrated networks using technologies such as Ethernet and leaky feeder systems. The systems available and equipment suppliers are reviewed.

Software packages for mine design and planning are reviewed. Programs available from Gemcom include Surpac, GEMS and Minex. The underground mine planning solution for Surpac can be applied to any mine layout, including narrow reef/seam conventional and mechanised mining, conventional and mechanised retreat longhole open stoping, cut and fill and sublevel and block caving. GEMS is used for collaborative geology and mine planning for open-pit and underground operations and Minex is designed for coal and other stratified deposits such as lignite, phosphate, bauxite and platinum. The Swedish SimMine package is currently only available for underground mines and new functions are being added to handle coal applications, with an open-pit package expected to follow. The software can be used to determine the most cost-effective way of developing a mine in relation to optimum fleet size, number of operators and shift schedule. Mintec’s software system is based on the MineSight package and provides tools for blast pattern design, end-of-period maps, economic and ultimate pit shells, life of mine and phase scheduling, road and ramp design and dump, spoil and dyke design for open pits and drift and stope design, ring design, automated shaft and vertical opening tolls for underground mines. MICROMINE software includes nine modules covering exploration, wire framing, resource estimation, pit optimisation, mining, scheduling, surveying and plotting. Mincom’s MineScape package can be used to rapidly assess the effect of changes in economic factors such as commodity prices, customer sales, cost assumptions and new geological and mine data. The company is also a leading supplier of enterprise asset management software. Maptek’s Vulcan modular software system can be used for exploration, geological modelling, resource/reserve estimation, mine planning, production scheduling and optimisation. CAE Datamine offers a range of software including exploration, geological modelling, strategic, Software packages for mine design and planning are reviewed. Programs available from Gemcom include Surpac, GEMS and Minex. The underground mine planning solution for Surpac can be applied to any mine layout, including narrow reef/seam conventional and mechanised mining, conventional and mechanised retreat longhole open stoping, cut and fill and sublevel and block caving. GEMS is used for collaborative geology and mine planning for open-pit and underground operations and Minex is designed for coal and other stratified deposits such as lignite, phosphate, bauxite and platinum. The Swedish SimMine package is currently only available for underground mines and new functions are being added to handle coal applications, with an open-pit package expected to follow. The software can be used to determine the most cost-effective way of developing a mine in relation to optimum fleet size, number of operators and shift schedule. Mintec’s software system is based on the MineSight package and provides tools for blast pattern design, end-of-period maps, economic and ultimate pit shells, life of mine and phase scheduling, road and ramp design and dump, spoil and dyke design for open pits and drift and stope design, ring design, automated shaft and vertical opening tolls for underground mines. MICROMINE software includes nine modules covering exploration, wire framing, resource estimation, pit optimisation, mining, scheduling, surveying and plotting. Mincom’s MineScape package can be used to rapidly assess the effect of changes in economic factors such as commodity prices, customer sales, cost assumptions and new geological and mine data. The company is also a leading supplier of enterprise asset management software. Maptek’s Vulcan modular software system can be used for exploration, geological modelling, resource/reserve estimation, mine planning, production scheduling and optimisation. CAE Datamine offers a range of software including exploration, geological modelling, strategic

The use of continuous miners and roadheaders in hard rock applications is reviewed. Pick-type machines use two types of cutting tool, indenters and drag bits. Both cause rock failure by inducing tensile cracking, and drag bits induce the cracks more directly than indenters but are considered less efficient. The cutting action of drag bits leads to tensile stresses in the bits, resulting in premature bit failure, and the sliding friction between the bit and the rock leads to high temperatures resulting in tool softening and rapid wear. Water jet-assisted cutting is used to remove heat from the cutter/rock interface and significantly reduces cutter forces. Water jets have been tested to pre-weaken the rock, and oscillating disc cutting with high-pressure water jets has undergone successful trials. Recent developments are described including the Aker Wirth tunnel boring system which uses a mobile tunnel miner concept and will undergo trials at the Norhparkes Cu-Au mine in Australia, a rapid tunnelling machine being developed by Atlas Copco, Sandvik's ICUTROC cutting concept, and Eickhoff's CM 2 continuous miner., The use of continuous miners and roadheaders in hard rock applications is reviewed. Pick-type machines use two types of cutting tool, indenters and drag bits. Both cause rock failure by inducing tensile cracking, and drag bits induce the cracks more directly than indenters but are considered less efficient. The cutting action of drag bits leads to tensile stresses in the bits, resulting in premature bit failure, and the sliding friction between the bit and the rock leads to high temperatures resulting in tool softening and rapid wear. Water jet-assisted cutting is used to remove heat from the cutter/rock interface and significantly reduces cutter forces. Water jets have been tested to pre-weaken the rock, and oscillating disc cutting with high-pressure water jets has undergone successful trials. Recent developments are described including the Aker Wirth tunnel boring system which uses a mobile tunnel miner concept and will undergo trials at the Norhparkes Cu-Au mine in Australia, a rapid tunnelling machine being developed by Atlas Copco, Sandvik's ICUTROC cutting concept, and Eickhoff's CM 2 continuous miner.