UV Basic Advantages
The basic requirements to the extraction technologies are reliability, productivity, efficiency and sustainability in terms of reduction of the environmental damage due to movement of bottom mineralized waters with silt to the surface together with minerals, and as a result of discharge of extraction waste to the near-surface ocean. The Underwater Vehicle (UV) is an advanced, reliable and environmentally friendly apparatus. Exactly these properties constitute its basic advantages. The Vehicle designers had the following task: to create an underwater vehicle, whose design would allow for maximally reliable and environmentally safe use at a great depth thanks to its improved strength, buoyancy and maneuverability. And our team succeeded in solving this task. Below you can learn about the UV technical capabilities.
UV Technical Advantages
The annual operating productivity of the “complex” is 1 mln tons of ferromanganese nodules (FMN) or other minerals. In order to attain the said productivity, subject to the data on deposit density of minerals over the ocean bottom, the UV is capable of handling the bottom areas at the rate of 0.5-0.7 m/sec.
The Vehicle can move with an average practicable speed of the industrial seafloor equipment, and the width of the tool for the collection of minerals is 12 meters. The solution of the task with such technical requirements was a serious challenge for the manufacturers of this complex.
The organization of extraction of minerals in such volumes with the help of the UV is conducted as follows: in order to carry out the extraction works it is necessary to use three ore carriers with the carrying capacity of at least 35,000 tons. The complex will consist, at the same time, of several Underwater Vehicles, whose productivity shall equal 300 tons each. This is the amount of nodules which our Vehicle is capable of carrying from the ocean bottom at a time during 4 hours: an hour - for immersion, one hour – for the collection of nodules, another hour – for surfacing, and one more hour – for unloading. Thus, the Vehicles will mine about 3,600 tons of FMNs per day, or 1.08 mln tons within a period of 300 working days (subject to weather conditions in the mining zone).
The works system has been planned in such a way that one ore-carrier, within one week, will be used as a nodules loading and storage base for one batch of the collected nodules, while another ore-carrier will deliver the second collected FMNs batch to the processing zone on the continent.
The requirement concerning high reliability of the production complex is not less challenging than the others. The disadvantage of the known vehicles used for the extraction of minerals from the ocean bottom is their insufficient strength, buoyancy and maneuverability that make it impossible to use them effectively at great depth. However, our team has managed to solve this problem through the capability of our Vehicle to operate with zero buoyancy. The UV can pass any obstacles on the ocean bottom by ascending and immersing (as may be necessary), and carries out its work in the most complicated conditions of the World Ocean at the depth of 6,000 meters.
In our Vehicle, the multitiered ballast system is filled with the syntactic material and forms a monolithic unit together with the body. In the course of operation in natural oceanic conditions, this system will demonstrate its high reliability – thanks to its capability of prompt replacement of power units, an emergency ascent unit and a work tool.
Our Vehicle is designed to carry out the mining operations with increased wave-impact load: the Underwater Vehicle is independent from the base vessel and equipped with a flexible hydrotransport system for pumping the harvested minerals to the vessel’s tank. In case of serious storms, when it is impossible to carry out the operations, the UV is
Another requirement, being not less complicated to fulfill, is trouble-free movement and fault-free operation of the bottom work tool in case of any undetected obstacles on the ocean bottom within the mining zone. This requirement is quite important as the Vehicle will inevitably run into undetected obstacles while collecting the FMNs and other mineral deposits. This problem was also solved by our team who used unique equipment for the Vehicle: while collecting the nodules, its body is moving over the bottom at the height of 3-5 meters. The chains of the work tool with ladles are moving in parallel with the Vehicle body with the help of a stand-alone regulated drive, and, in their hanging position, sliding along the bottom. The specially designed (chain) ladles draw the minerals together with the silt layer; the silt drains though their latticed walls and bottom, while the solid minerals are conveyed to the tank. The chains with ladles slide over the surface of ocean juts: such design allows the tool for the collection of nodules passing the obstacles of almost 1.5-2 meters high, without a need to interrupt mining operations. Besides, the Vehicle is capable of autonomous motion by means of maneuvering devices along the trajectory of the certain pathway. Such system makes it possible to attain the required efficiency and operating productivity of the production complex. Our team, however, has taken into account that on the way of dozens of kilometers in the course of handling the bottom surface at the specified rate, the Vehicle will inevitably and quite often face undetected obstacles.
UV Environmental Advantages
One of the advantages of our Underwater Vehicle is the compliance with the mandatory environmental requirements to vehicles operating in the underwater world that is so sensitive to any external impact. Our mining technology is based on a general principle: minimum environmental impact on the sites under development.
A problem of carrying the silt and near-bottom waters to the surface is solved as follows: the storage tank has holes through which the overboard water drains while the Vehicle goes up, thus providing continuous exchange and displacement of water layers in the course of surfacing. Undamaged nodules are conveyed to the base vessel.
The Underwater Vehicle is also equipped with water-jet nozzles to remove all living organisms out of the nodules mining site. Taking into account the fact that the mining operations will be carried out in different sites of the licensed field and the shifting of the operations with the stream, the nodules harvesting will be performed in a moderate (partial load) mode at different sites, thus allowing the gradual recovery of the earlier affected areas.
UV Economic Advantages
The UV operation economic advantages consist in the following: in the course of mining operations, it is necessary to provide equal volume of the filled space of the ballast system used for the immersion, and for the pumping out - in the course of surfacing. Meaning that, during the surfacing process, the UV turns into positive buoyancy and, using its physical properties, autonomously carries the load from the bottom to the surface (from the depth of 0 to 6,000 meters). Thus, the deeper the mineral deposit – the more efficient the mining per one ton of cargo is, as compared to the conventional technology.
In order to organize the efficient mining operations, it is necessary to use several ore-carriers with the carrying capacity of at least 35,000 tons, as well as several underwater vehicles, with the capacity of 300 tons each. The system of works is planned in such a way that the first ore-carrier will be used, within a week, as a base for loading and storage of one batch of the harvested nodules, while the other ore-carrier will deliver the second harvested batch to the on-shore processing facilities.