obstacles that must be considered during the planning phase include residential areas , roads , and rivers . “ Today , we can design curved overland conveyors of up to twenty kilometres or longer without the need for a transfer tower ,” says Neubert . The conveying capacities of a system like this are more than 20,000 tons per hour .
The right layout “ We use our BEUMER Overland Layouting Tool to ascertain the ideal layout for the system ,” says Neubert . “ It generates a digital 3D model of the conveyor in the virtual landscape during project planning , more or less automatically .” The critical topography data can either be provided by customers , or drones are used to capture terrain data . “ These 3D visualisations are also ideal for supporting mining companies in their PR relations work ,” explains BEUMER expert Neubert . Important factors such as ‘ cut and fill ’ volumes , i . e . the necessary excavation work , and the required steel structures for the conveyor can be evaluated and illustrated on this basis . “ This procedure considerably accelerates the project planning process and enables us to provide project-critical data to the customer at an early stage of the project ,” says Neubert .
Ongoing development in conveying technology The 1990s saw BEUMER Group start its development into one of today ’ s leading suppliers of pipe conveyors . In these systems , the idlers form the belt into a closed pipe that protects the material to be transported against external influences and the environment from emissions such as dust and odours . This conveying solution is therefore ideally suited for fine bulk materials such as ore concentrates . Pipe conveyors also allow tighter curve radii and greater angles of inclination compared to conventional troughed belt conveyors .
However , what if bulk material with large grain sizes requires a larger pipe diameter ? The rule of thumb here is that the pipe diameter should be about three times the maximum grain size . To solve this problem , the BEUMER Group developed the U-shape conveyor .
“ This variant combines the advantages of a troughed belt conveyor with those of a pipe conveyor ,” says Neubert . The idlers form the belt into a U-shape rather than a pipe . The U-shape conveyor enables tighter curve radii than a troughed belt conveyor and higher mass flows than a pipe conveyor and also protects the conveyed material from environmental influences and the environment from material loss and emissions .
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Electrowinning systems for mineral processing applications
used to recover copper . However , as with any hydrometallurgical process , it is necessary to bleed a portion of the electrolyte to control impurities in the circuit .
In the case of ( SX-EW ) operations , the impurity bleed removed often flows to the raffinate pond , which adversely affects the efficiency of the leaching process in the heap . According to Fick ’ s Law , this practice hampers leaching performance due to increased cationic load ( copper in the bleed solution ) and reduced acid to the heap leach . However , by directly recovering copper cathode from the bleed stream using emew electrowinning before it enters the raffinate pond , several benefits can be obtained :
• Up to a 10 % improvement in copper recovery from the heap
• A reduction of 15-30 % in copper levels in the raffinate
• Lower consumption of fresh acid
• Reduced working capital requirements
• Increased production of copper cathode
The utilization of emew electrowinning technology to recover high-grade , marketable copper cathode from SX-
EW bleed streams results in decreased copper levels returning to the heap , thereby enhancing leach efficiency and improving overall copper recovery from the heap . Incremental copper production at very low marginal cost .
Furthermore , as the heap approaches the end of its operational life , it becomes crucial to recover the maximum amount of copper units to ensure profitability and successful decommissioning . The unique emew electrowinning technology enables the recovery of more soluble copper units from spent heap leach ores than any other electrowinning technology available .
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