This Paper is dedicated to Borehole Mining (BHM), the method of remotely extracting rock material through boreholes by high-pressure water jets. The technology is based on in-situ jet cutting of rock mass, creating slurry, and delivering it to the surface.
Remote operation in this case scores significant advantages over traditional mining methodology, the most important of which are: total personnel safety, high mobility, minimal environmental impact, and low capital/operational cost. Since these advantages, such regions as the World's Offshore and Polar Zones become the most appropriate BHM's application areas.
On-land developed, Borehole Mining is well known in the "Continental" engineering community. The recent BHM's list of successfully extracting minerals includes Coal, Uranium, Iron Ore, Titanium, Zirconium, Kimberlite, Bauxite and several more. This list also includes stimulation of water, oil and gas production. The depth of operation just exceeded 1 km. In addition to exploration, mining and stimulation, the array of BHM application also includes environmental and underground construction areas, river banks reinforcement and several more.
Despite widespread acceptance of the theory behind BHM, and its recent and verifiable track record in the field, few offshore specialists or professionals are aware of the explosive financial potential of Borehole Mining. Meanwhile, no known obstacles prevent application of BHM from the water surface. Owing to aggressively pursued standardization, the list of required equipment includes only a vessel or a floating platform, with a pump station and the Borehole Mining Tool. This paper is to introduce the "ground" Borehole Mining technique and experience and present the opportunity of BHM application from water surface.
Few innovations in mining science have been so universally sought as a viable method of remotely controlled, automated subterranean excavation - the extraction of deeply buried natural resources while personnel and controls remain safely above ground. After years of design, laboratory tests, field trials, and actual operations, that dream has been realized, and is known today as Borehole Mining.
Originally developed as a remote underground exploration and mining method, Borehole Mining (or BHM) soon found applications in related areas such as underground construction, environmental projects, abatement solutions, and more. The extension of exploitability presently under review is mineral extraction below the seabed.
The BHM method is based on in-situ water jet cutting of rock mass, creating a slurry and delivering it to the surface. In Fig. 1 the schematic of the method is presented. The borehole mining tool 1 is lowered into the borehole 2 and high pressure water 3 is pumped down. At the bottom part of the tool, one portion of that water comes out through the hydromonitor nozzle 4 in a shape of water jet 5 and cuts the material 6 creating slurry 7. The other portion of high pressure water then comes to the eductor 8, which produces a vacuum.