Technology and equipment of deep-sea mining: State of the art and perspectives

Rising demand for minerals and metals in high-tech and new energy industries has led to a great interest in exploration of seabed mineral resources. Such resources, including polymetallic nodule (PMN), polymetallic sulphide (PMS), and cobalt-rich ferromanganese crust (CFC), are considered as an alternative source of metals to terrestrial deposits. Although a considerable number of sea trials of deep-sea mining have been carried out, the deep-sea mining does not achieve the commercial exploitation due to the complexity of deep-sea mining system and deep-sea mining environment. In fact, to achieve commercial deep-sea mining, the technology and equipment of deep-sea mining are the key points. Therefore, the present study presents the development of the technology and equipment of deep-sea mining. It commences with a requirement of technology and equipment for deep-sea mining, including environmental impact, reliability, energy cost, efficiency, etc. Then, a historical perspective and present-day effort related to deep-sea mining vehicles are given, which highlights the evolution of collection mechanism and walking mode of deep-sea mining vehicle. Subsequently, the present study discusses the operation of subsea lifting system and surface support system, shedding light on the crucial equipment and processes. The challenges and prospects in the deep-sea mining are presented in final, including environmental protection, self-propelled crawler, hydraulic pipeline lifting, and intelligent equipment, etc.