Preliminary Economic Feasibility Study of Ferromanganese Nodule Mining by Mechanical Lifting and Small-Scale Collectors

Ferromanganese nodules have been recognized as a potential future metal source for over 50 years. Many research and development efforts have been conducted by many organizations. Most of the efforts have been concentrated into the mining technologies especially for hydraulic lifting through riser pipes with bulk-scale nodule collector. However, no commercial mining venture exists. Uncertainty in the economy of nodule mining is considered to be the reason for this. In order to improve the economy, a mining subsystem based on mechanical lifting and small-scale collectors is proposed and the preliminary economic feasibility is examined in this study. The benefit was at a favorable level compared with that using hydraulic lifting with bulk-scale collector. From the viewpoint of environmental impact assessment, environmental considerations of deep-sea sediment plume are explained.

VGG19 Network Assisted Joint Segmentation and Classification of Lung Nodules in CT Images

Pulmonary nodule is one of the lung diseases and its early diagnosis and treatment are essential to cure the patient. This paper introduces a deep learning framework to support the automated detection of lung nodules in computed tomography (CT) images. The proposed framework employs VGG-SegNet supported nodule mining and pre-trained DL-based classification to support automated lung nodule detection. The classification of lung CT images is implemented using the attained deep features, and then these features are serially concatenated with the handcrafted features, such as the Grey Level Co-Occurrence Matrix (GLCM), Local-Binary-Pattern (LBP) and Pyramid Histogram of Oriented Gradients (PHOG) to enhance the disease detection accuracy. The images used for experiments are collected from the LIDC-IDRI and Lung-PET-CT-Dx datasets. The experimental results attained show that the VGG19 architecture with concatenated deep and handcrafted features can achieve an accuracy of 97.83% with the SVM-RBF classifier.

Development and Subsea Testing of Polymetallic Nodule Crusher for Underwater Mining Machine

Polymetallic nodules found in the deep oceans are viewed as potential resources for meeting the world's demand of many metals in the near future. Polymetallic nodule mining systems require subsea crushing systems for reducing the size of nodules to facilitate energy-efficient and safe pumping through risers of optimum size. Polymetallic nodules are friable, and deep-sea crushing has to be done with care to minimize the formation of fines, while obtaining the required size reduction. The crusher could also encounter objects with greater hardness during operation like small rocks, splinters, long fish bones, and shark teeth. All components in the crusher should be capable of operating in the deep ocean environment, which is hyperbaric and sediment laden. The equipment should be compact with minimum weight. Reversal of direction and dumping arrangements in the event of stalling are other essential design requirements. An underwater crusher capable of crushing mined nodules from a maximum size of 100 mm to a crushed size of 30 mm was developed using principles of design synthesis. The crusher was tested in land and integrated into a remotely operated crawler-based underwater mining machine that could mine and pump nodules through a flexible riser. The system was tested using artificial nodules at 512-m water depth off the Malvan coast in the Arabian Sea. This paper describes developmental methodology, land-based performance tests, and sea trials conducted on the developed crusher.

Near-Field Analysis of Turbidity Flows Generated by Polymetallic Nodule Mining Tools

The interest in polymetallic nodule mining has considerably increased in the last few decades. This has been largely driven by population growth and the need to move towards a green future, which requires strategic raw materials. Deep-Sea Mining (DSM) is a potential source of such key materials. While harvesting the ore from the deep sea by a Polymetallic Nodule Mining Tool (PNMT), some bed sediment is unavoidably collected. Within the PNMT, the ore is separated from the sediment, and the remaining sediment–water mixture is discharged behind the PNMT, forming an environmental concern. This paper begins with surveying the state-of-the-art knowledge of the evolution of the discharge from a PNMT, in which the discharge characteristics and generation of turbidity currents are discussed. Moreover, the existing water entrainment theories and coefficients are analyzed. It is shown how plumes and jets can be classified using the flux balance approach. Following that, the models of Lee et al. (2013) and Parker et al. (1986) are combined and utilized to study the evolution of both the generated sediment plume and the subsequent turbidity current. The results showed that a smaller sediment flux at the impingement point, where the plume is transformed into a turbidity current, results in a shorter run-out distance of the turbidity current, consequently being more favorable from an environmental point of view.

Experimental Investigation Into Soil and Mechanical Pick-up Device Interaction in Nodule Mining of Deep Seabed

This research is focused to experimentally analyze the nodule picking efficiency of a deep sea mechanical pick-up device developed by National Institute of Ocean Technology, India. Experiments were conducted in a simulation tank with different operating parameters on a bentonite soil bed simulating the deep seabed and artificial nodules. Digging depth of the pick-up device, its angle and haulage velocity were the input variable parameters. From the experimental investigations, the values of the operating parameters that result in the highest pick-up efficiency were identified. The nodule picking efficiency increased as the pick-up device inclination was increased and reduced when the digging depth and haulage velocity were increased. The maximum nodule picking efficiency was 85% when the haulage speed, digging depth, and pick-up device inclination were 0.0375 m/s, 25 mm, and 30°, respectively. The research outcome would be useful in actual deep seabed conditions for efficient polymetallic nodule mining. Multiple mining machines with increased working width are proposed for large-scale operations.

RV SONNE Fahrtbericht/Cruise Report SO268 - Assessing the Impacts of Nodule Mining on the Deep-sea Environment: NoduleMonitoring, Manzanillo (Mexico) – Vancouver (Canada), 17.02. – 27.05.2019

Cruise SO268 is fully integrated into the second phase of the European collaborative JPI-Oceans project MiningImpact and is designed to assess the environmental impacts of deep-sea mining of polymetallic nodules in the Clarion-Clipperton Fracture Zone (CCZ). In particular, the cruise aimed at conducting an independent scientific monitoring of the first industrial test of a pre-protoype nodule collector by the Belgian company DEME-GSR. The work includes collecting the required baseline data in the designated trial and reference sites in the Belgian and German contract areas, a quantification of the spatial and temporal spread of the produced sediment plume during the trials as well as a first assessment of the generated environmental impacts. However, during SO268 Leg 1 DEME-GSR informed us that the collector trials would not take place as scheduled due to unresolvable technical problems. Thus, we adjusted our work plan accordingly by implementing our backup plan. This involved conducting a small-scale sediment plume experiment with a small chain dredge to quantify the spatial and temporal dispersal of the suspended sediment particles, their concentration in the plume as well as the spatial footprint and thickness of the deposited sediment blanket on the seabed.

The Development History and Latest Progress of Deep-Sea Polymetallic Nodule Mining Technology

Deep-sea polymetallic nodules are a mineral resource with potential for commercial development. Due to the unique deep-sea environment in which they are found, specialized technology and equipment are required for their extraction. In this paper, firstly, the development of deep-sea polymetallic nodule mining technology is classified into three stages, and its characteristics are summarized. Moreover, the results from research into deep-sea polymetallic nodule mining technology are analyzed, including proposals for mining systems, research into key technologies, basic scientific problems, and proof of technical feasibility from sea tests. Secondly, the testing of the collector prototype and the environmental impact assessment study of Global Sea Mineral Resources NV, as well as the progress of the deep-sea polymetallic nodule mining test project in China, are introduced. On this basis, the opportunities and challenges brought by the fast-growing demand for electric vehicles to the development of deep-sea polymetallic mining technology is analyzed, and a possible technical scheme for a mining system and the trends in its development towards high reliability and high standards of environmental protection according to the requirements of commercial exploitation are explored. This provides a reference for the research and development of high-efficiency technology and equipment for the mining of deep-sea polymetallic nodules.