Desliming Device for Pretreatment of Polymetallic Nodules in Deep-Sea Mining
A seabed collector vehicle usually carries a large amount of sediments during mining seabed polymetallic nodules.For reducing the environmental impact caused by tail water discharged in the mining,two kinds of high efficiency and low diffusion desliming pretreatment devices,with twine-drum spiral structure and a direct discharge device with arresting mesh structure,respectively,have been developed,which integrates a jet-assisted transport testing equipment,and is also equipped with an online monitoring system.The desliming effect and environmental performance of the developed device was evaluated by performing computational fluid dynamics simulations and laboratory tests.It is found that the direct discharge device with arresting mesh can pretreat tails with desliming rate over 98%,and this pretreatment device can make quick separation of nodules from sediment,and also lead to subsequent quick settlement of the separated sediment,thus effectively controlling the plume caused by collector in the mining.It is concluded that this developed pretreatment device can improve the lifting efficiency in the mining and mitigate the pollution of tails in the deep-sea mining from the source.