In 2015-2018, the Rubin Design Bureau led an effort implementing its project Development of Underwater (Under-ice) Seabed Mining Technologies for the Arctic Zone, dubbed Iceberg. It encompassed multiple initiatives and researches aimed at designing technologies and assets, providing full-fledged subsea extraction of oil and gas in permanent ice zones.
For starters, it is an underwater power facility to power mining and extraction equipment.
Designed in a concerted effort with the Afrikantov Experimental Design Bureau for Mechanical Engineering, the nuclear power plant is consistent with the IAEA nuclear safety regulations and comprised of an autonomous unmanned underwater facility, combining one or several modules engaged simultaneously to carry the load. The module boasts a useful output of 16mW with provisions made for an increase to 25mW.
The reliability of the unmanned facility without checks and maintenance throughout the entire operating period is provided by using an integral reactor, boasting a full-fledged natural circulation of the primary circuit coolant throughout the entire range of power output, and cassette-type core, reducing the number of auxiliary systems and gear, as well as by integrating highly-automated control and radiation and technological monitoring systems.
Second, the researchers looked into the issue of drilling vertical, slant and horizontal test pits and development wells.
To this end, Rubin approached the Gubkin Russian State University of Oil and Gas. Their team came up with a solution based on a remote drilling technology with the telemetry transmitted to shore-based control posts. The adopted architecture of the future drilling system includes several independent modules: underwater drilling, drilling fluid and cement slurry preparation, drilling mud cleaning, control, power supply and communication, as well as removable cartridge storing.
The solution implies the use of an open, unsheltered drilling unit. The equipment of the underwater drilling system is not sealed and operates under the excess pressure. The job to develop the drilling equipment, gear for tripping operations and systems for storing, transporting and feeding pipes and pipe tools was again given to the Afrikantov Experimental Design Bureau for Mechanical Engineering.
Provisions have been made to provide for replacement of equipment and gear in all modules, when they are already deployed and in operation. To hedge risks of developing an emergency during drilling operations, the designers adopted a continuous drilling approach with uninterrupted drilling mud circulation. They also were thoughtful enough to use drill fluids and cement slurry based on liquid components.
During the underwater drilling system project, the St. Petersburg State Polytechnic University combined efforts with the Kurchatov Institute to develop a virtual simulating model, offering calculations of the system operation in various operating conditions. The technology is instrumental in getting the required expertise and knowledge by the time the system goes into production and ultimately operation, thus, reducing costs related to manufacturing and testing various mockups.
Another aspect covered in the project is the development of underwater seismic survey system, providing various surveys and researches, from 2D areal to more detailed 2D-3D and to 4D monitoring, in any conditions and seasons, regardless of the sea state.
A number of recent researches conducted by different companies suggest that in conditions of winter and thick ice fields developed over years traditional seismic survey ships are almost useless. Even in the ice-free part of the Barents Sea winter operations are impeded by the sea state, fog, icing of the ship and mounted equipment, as well as short daylight hours and polar night conditions.
To this end, the designers offered an underwater seismic survey system of a submersible platform based on a nuclear submarine and towed seismic streamers, as well as self-sustained seabed stations and streamers, and seismic wave emitters. Besides, the system would include TV-controlled vehicles, deploying and collecting survey assets.
The Iceberg project encompasses multiple initiatives and researches aimed at providing subsea extraction of oil and gas in permanent ice zones
In a concerted effort with the Institute of Oil and Gas Problems of the Russian Academy of Sciences, Rubin figured out a new 3D survey technology conducted from a nuclear submarine. It stipulates deployment of short streamers to set up a 100x100m self-registering space array. For this, the submarine would carry retractable bow- and stern- mounted wings comprising turning surfaces for automatic deployment of streamers. Besides, provisions have been made for reeling off a long streamer for 2D surveys.
For seabed surveys, the Experimental Design Bureau of Oceanological Engineering, a branch of the Russian Academy of Sciences, rendered its assistance in designing options for deployment and collection of seabed seismic stations and streamers from the bottom.
The system based on various seabed seismic survey assets is stowed aboard a submersible vehicle in pressurized floodable tubes.
As part of the initiative, the designers considered a survey technology, stipulating equipment of tubes with survey kits strapped onto unmanned underwater vehicles.
Prompted by the Iceberg project, Rubin suggested a flexible seismic survey technology based on the employment of a group of autonomous underwater vehicles providing for a variety of under-ice survey options both on the seabed and in water layers.
Such system is suitable for deployment from an ice-capable surface carrier as well.
Another subproject was aimed at developing an underwater system for transportation, installation, and maintenance of underwater oil and gas extraction systems in heavy ice conditions.
Basically, it is a submersible twin-hull vehicle. Its cargo bay is fitted between the hulls and connecting them crossbars. The sails towering over both hulls house cargo lifting mechanisms facing the cargo bay. All technical solutions have been patented in Russia.
For the main propulsion adopted have been two steering pods, providing required maneuverability, particularly at low speeds. Positioning and stabilization when the main propulsion idles is achieved by employing retractable fully-articulated pods and vertical thrusters.
The architecture may come in handy for a wider range of missions, to include seismic surveys, collection of oil products below ice or nodules from seabed for that matter.
Finally, the designers did not leave unattended the safety and security aspect, either. The solution came in the form of a comprehensive safety and security system. It will provide safe operation of underwater oil and gas extraction systems in remote Arctic regions. It has been shaped by three major safety and security aspects of operations of underwater installations. First comes the issue of industrial safety provided to the extent of monitoring technical status of the equipment, technological procedures, ice situation and ground condition. Then it is ecological safety that also needs attention. It encompasses monitoring of environment, as well as checks for process fluid leaks and hydrocarbon emissions. And finally, unlawful interference with the operations of underwater systems is an issue that calls for special countermeasures.