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www.sea-technology.com August 2016 / st 31 D eep-sea solid minerals present a largely untapped re- source, particularly manganese nodules, cobalt-rich crust and seafloor massive sulfides. Since the 1990s, hu- mans have been studying how to exploit cobalt-rich crust from deep-sea basins using the experiences of mining manganese. The challenge is how to strip the thin upper layer of cobalt-rich crust from substrate rock. While American, Japanese and Russian scholars have created the spiral roller mining method, the College of Mechanical and Electrical Engineering of Central South University in China has designed a spiral cutting vibration platform and conducted research on breaking ore, related mechan- ical properties, the collection of minerals, energy consumption and simulation. Breaking up deep-sea solid minerals still uses mechanical and hydraulic methods, which inevitably result in a lot of waste rock in the process of mining. To try to minimize waste byproduct, our project team has designed high-voltage discharge equip- ment to break up deep-sea solid minerals in the water. Many scholars in China and abroad have studied high-voltage impulse. For example, Tan Zhenyu et al carried out fractal simula- tion of steamer discharge in liquid water; Deng Heming et al investigated two-phase mixture discharges and the effects of mac- roparticle size; J. Biela et al proposed a high- voltage electrical design to break rock via plasma channel; Huang Guoliang et al simu- lated the process of breaking rock in water; and so on. Although high-voltage impulse is widely used in general, it is not widely used in the field of mining, so it is worth further study. We undertook a study that involved ana- lyzing the formation of a plasma channel in solid mineral, enabling us to study energy distribution with respect to breaking up min- eral rock. We experimented with this new technology in the lab, looking to apply it to deep-sea mining. Testing Direct discharge in seawater is a new method for breaking solid minerals. A testing device was designed to break ores via high voltage. It is composed of posi- tive and negative copper electrodes and was used for ex- perimentation in the lab. Solid minerals for testing were supplied from the China Ocean samples management administration. As part of our high-voltage impulse experiments, we used output voltage up to 50 kV, with frequency up to 200 Hz and an impulse period up to 200 ns. The two electrodes were put on the surface of a solid mineral, leading to the formation of a plasma chan- Deep-Sea Mineral Extraction Via High Voltage Using High Electrical Charge to Break Up Solid Minerals By Jianhua Hu • Shaojun Liu• Ruiqiang Zhang (Top) The plasma channel is formed in a solid mineral in seawater. (Bot- tom) A cloud diagram of an electric field.