MATERIALS HANDLING
volume, and this then must be disposed of safely.
Te concentrate goes for refining and finishing, where the processes contain corrosive fluids, adding another dimension to the equipment design requirements. Erosion wear becomes less significant, and corrosion becomes the bigger challenge.
EMW heavy-duty slurry pump
concentration, density and hardness of the solids.
Typical mine site
Comminution is where the ore starts off as large rocks and undergoes a series of steps to reduce its size so that the desired metal may be separated from the rock. Te initial crushing and screening are dry processes and water is not added into the process until the ore gets to the grinding mills. Here the particle size becomes small enough to liberate the commodity from the rock through a separation process before it is finally thickened for the refining and finishing process. Methods for separation depend on the ore type, e.g. screening, gravity, dense medium, magnetic or flotation, resulting in the desired product in the form of a concentrate. Te waste generated from the process forms the largest
and thickening followed by the transport of the desired product to the refining and finishing process, whilst the waste has to be safely disposed of. For extraction, to ensure safe mining
residual or incoming ground water must be removed continuously. Water ingress may come from a high water table as well as from rainfall, localised flooding or snow melt. Deeper mines may also be affected by subterranean waterways or pockets of water in the ore body. Dewatering fluids are defined as being contaminated with <50g/l of fine solid particulates that may be abrasive, and the carrier fluid may also have some corrosive properties due to ground conditions. Fluids with a solids content above this are classified as slurry, with the classification dependent on size,
QUARRYING Quarry pits are essentially smaller open cast mines, and the requirements for dewatering the working areas are very similar to those in mining. Te product being extracted may be inert, e.g. sand, rock, gravel, etc., or containing minerals such as kaolin. With mineral quarrying, the key difference from mining is that here the product is often extracted by hydro-mining and the resultant slurry pumped out of the pit for further processing. One of the consequences of this is that stones and rocks can also find their way into pumping equipment, and the hydraulic and material design must allow for this. Pumps with large passage passing capability are required, often mounted inside the quarry pit, operating on a suction lift. Deeper quarries require correctly configured in-line booster pumps or intermediate pump stations. Tis subsequent processing of the
product is generally done close to the quarry pit, and a range of slurry and water handling pumps are used within the plant.
HPH mine dewatering pump
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