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.

Development of pneumatic test rig protection for elements of underwater oil & gas production system

Object and purpose of research. This paper discusses protective structure for a pneumatic test rig intended for experiments with the elements of underwater mining system at KSRC Open Test Tank. The purpose of this study was to justify the design parameters ensuring the safety in case of an emergency leakage from the tested equipment. Materials and methods. The study followed the methods of computer-based simulation to analyse gas dynamics of leakage escalation and its effect upon the protective structure. Main results. This paper presents development results of a floating submersible protective structure, with analytical estimates of hazardous factors and protection robustness in case of a hypothetical emergency during pneumatic tests of equipment. Conclusion. Protective structure design suggested in this paper for given conditions of submerging into an open tank and given conditions of pneumatic tests (pressure 69 MPa, nitrogen volume 1 m3) prevents hazardous leakage to the environment. Accordingly, these tests will be safe for both personnel and test facilities.

DEVELOPMENT OF MARINE HYDROCARBON RESOURCES USING UNDERWATER PRODUCTION SYSTEMS

The paper examines the marine resources of hydrocarbons and their development by underwater extraction, substantiates the relevance and prospects of marine technology. The article presents innovative devices for oceanological underwater mining. The characteristics of the types of marine underwater equipment are given and the factors influencing the development and selection of innovative technical structures in the water areas are investigated.

Bucket positioning and its load content during mining in inundated mineral deposit

In this paper, we discuss an issue of underwater mining and why modern mining equipment does not fit this purpose. Working in such complicated conditions often has an unsatisfying performance level. We analyzed the processes of mining materials that have not been preliminary dewatered. We also describe variations of positioning system and the importance of their use in underwater mining. A theoretical analysis of excavation process with a perforated bucket has been performed. We present a formula that allows assessing extent of bucket loading by parameters of the working face development. Another formula that allows determining the number of excavation cycles required to complete the bucket loading. A formula for parametric length of working face arc determining by the given stratum depth was introduced. Basing on the acquired formulae, we formulated another one that determines the number of excavation cycles necessary for complete face development for specified cutting parameters. An aggregated graph showing the dependency of the number of excavation cycles on peat shavings width and thickness variables. On the basis of the resulting graph, the best variant for the most complete bucket loading was chosen. In conclusion, we highlighted the peculiarities of underwater mining.

Underwater Localization System Combining iUSBL with Dynamic SBL in ¡VAMOS! Trials

Emerging opportunities in the exploration of inland water bodies, such as underwater mining of flooded open pit mines, require accurate real-time positioning of multiple underwater assets. In the mining operation scenarios, operational requirements deny the application of standard acoustic positioning techniques, posing additional challenges to the localization problem. This paper presents a novel underwater localization solution, implemented for the ¡VAMOS! project, based on the combination of raw measurements from a short baseline (SBL) array and an inverted ultrashort baseline (iUSBL). An extended Kalman filter (EKF), fusing IMU raw measurements, pressure observations, SBL ranges, and USBL directional angles, estimates the localization of an underwater mining vehicle in 6DOF. Sensor bias and the speed of sound in the water are estimated indirectly by the filter. Moreover, in order to discard acoustic outliers, due to multipath reflections in such a confined and cluttered space, a data association layer and a dynamic SBL master selection heuristic were implemented. To demonstrate the advantage of this new technique, results obtained in the field, during the ¡VAMOS! underwater mining field trials, are presented and discussed.

Combined Mining Technologies for Coal Deposits (Review)

The paper discusses the main disadvantages of strip and underground mining methods and possibilities of eliminating the disadvantages through introducing a combined technology of coal deposit mining. Combined coal mining technology is the method comprising elements of several geotechnologies, for example, underground and strip mining, as well as, possibly, underwater mining, borehole and other techniques of deposit mining. The combined coal mining technology provides for unified layout for opening, development, production and processing of reserves for the whole LoM on the basis of general technological solutions made in advance. Such complex solutions for opening and development of deposit reserves within the opencast and underground mining contour allows minimizing the volume of openings and reducing the time for commissioning, investment costs, as well as decreasing the costs for aerage, drainage, rock mass hauling and land reclamation. Substantiation of deposit opening options should comprehensively take into account technical, organizational, and economic factors [34–37]. Analysis of the options as exemplified by the Makar’evskoe coal deposit development in Kuzbass allows to conclude that the combined method is promising and promotes increasing optimal volumes of coal production, while reducing the deposit development time by about 15 %, and increase the net present value compared to underground and opencast mining options more than 5 times.

DEVELOPMENT OF THE TECHNOLOGICAL POTENTIAL OF AUTONOMOUS UNDERWATER VEHICLES

Перспективы создания подводных роботов – автономных и телеуправляемых необитаемых подводных аппаратов (АНПА, ТНПА) нового поколения связаны с разработкой технологий гибридных необитаемых подводных аппаратов (ГНПА), в которых интегрированы функции АНПА и ТНПА. Проблема состоит в значительном расширении технологических возможностей АНПА за счет оснащения их новыми инструментами, совершенствования систем бортового управления, вовлечения оператора в технологический процесс для оперативного контроля хода работ, порядка и условий выполнения принципиально новых технологических операций. ГНПА может выполнять широкий спектр бесконтактных работ, выходить к объекту обследования в соответствии с заданной программой, выполнять действия, связанные с формированием канала информационного обмена с постом управления, и далее выполнять контактные операции в супервизорном режиме. Первоочередные задачи создания гибридных аппаратов состоят в развитии функциональных свойств АНПА, включая: интеллектуализацию системы бортового управления, организацию супервизорного управления с включением оператора в процесс управления, расширение инструментального оснащения и оптимизацию конструктивных решений, организацию сетевых средств подводной навигации, организацию инфраструктуры подводного базирования аппарата при выполнении длительных работ по обслуживанию подводных добычных комплексов. В работе показана принципиальная возможность создания ГНПА на основе робототехнических комплексов и их систем, созданных в ИПМТ ДВО РАН за последние годы. Prospects of designing autonomous and remotely operated underwater vehicles (AUV and ROV) of the new generation rely on developing hybrid autonomous and remotely-operated vehicles (ARV), which combine functions of AUV and ROV. It is necessary to expanse significantly AUV's technological capabilities by equipping it with new instruments, upgrading onboard control systems, involving operators in the technological process for real-time control of work progress, and execution order and conditions of novel technological operations. ARV is capable of performing a wide specter of contactless operations: approach the target of research according to the stated program, perform operations related to establishing a data exchange channel with control station, and then carry out contact operation in supervisory mode. Priority tasks of hybrid vehicles designing consist of the development of AUV's functional properties, including: intellectualization of onboard control systems; provision of supervisory control involving an operator in control flow; expansion of instrumentation and optimization of structural solutions; providing a network means for underwater navigation; providing an infrastructure for underwater deployment while carrying out long-term missions on the maintenance of underwater mining complexes. Work demonstrates a principal achievability of designing an ARV based on robotic complexes and their systems developed in the IMTP FEB RAS for the past years.

CALCULATING AND FORECASTING HARDWARE PERFORMANCE FOR UNDERWATER MINING OF SOLID MINERALS

In this article, new classification features of machines for underwater mining of solid minerals are proposed, such as their cyclical and continuous operation. It is established that for cyclical machines starting from a depth of 300…500 m the speed of movement of the executive body (trawl, drag, etc.) and the concentration of minerals do not have a determining value. When selecting equipment for underwater mining at a depth of more than 100 m and forecasting its performance, it is proposed to take into account the depth of development for cyclical machines, the speed of lifting and lowering of the executive body, and for continuous machines, reliability indicators, for example, the readiness coefficient determined by expert means.