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These tanks
provide live storage
to balance
fluctuations in
pipelines, plus find
numerous in-plant
uses. Properly
sizing them will
yield an economic
benefit.
When minerals such as iron and copper are mined in remote locations, it is common to locate the beneficiation plant near the mine site, then transport the concentrate to the refinery, frequently by ship. A slurry pipeline between the beneficiation plant and the marine terminal facility is an economical means of transport. Variations in the feed supply and terminal demand are reasons for normally providing 8-24 h or more of live storage capacity at each end of this setup.
Agitated slurry tanks are also commonly used in the plant in leaching operations and to provide feed holdup, among other applications.
Pipeline systems are designed to operate within a relatively narrow range of flows to optimize hydraulic efficiency. While too-high a pipeline velocity will lead to abrasion and high friction, toolow a one can result in sand-out. Constancy is accomplished by installing these agitated storage tanks to smooth out variations or stoppages in the feed rate from the beneficiation facility or demand at the terminal.
Vessel heights and diameters are usually selected prior to any agitator design. Since the vessel cost for a fixed live-bottom volume is minimized at a slurry-height-to-vessel dia. ratio ZIT of about 1.05, this value is frequently selected and fixed. However, in actual operation, agitator and power costs...