ocean mining techniques

1. Ocean Mining TechniquesOcean Mining Techniques
K. Sandeep vamsiK. Sandeep vamsi
M.Sc, M.Phil.M.Sc, M.Phil.

2. INTRODUCTIONINTRODUCTION
 Minerals have become very useful in our dailyMinerals have become very useful in our daily
life.life.
 More consumption of these minerals is leadingMore consumption of these minerals is leading
to high demand.to high demand.
 In majority of the countries, lack of minerals orIn majority of the countries, lack of minerals or
depletion of minerals from the resources isdepletion of minerals from the resources is
leading to high demand for particular mineralsleading to high demand for particular minerals
during peace and also during the war time.during peace and also during the war time.

3.  Lets take an example of India having highLets take an example of India having high
demand for minerals, the last two warsdemand for minerals, the last two wars
have caused depletion in resources inhave caused depletion in resources in
petroleum, tin, lead and zinc.petroleum, tin, lead and zinc.
 Lead, zinc and tin supply is put at onlyLead, zinc and tin supply is put at only
about 17-20 years from the knownabout 17-20 years from the known
sources.sources.
 Some of the critical minerals areSome of the critical minerals are
petroleum, petroleum products, S, Pb, Zn,petroleum, petroleum products, S, Pb, Zn,
Cu, Ni, Hg, pt and minerals like industrialCu, Ni, Hg, pt and minerals like industrial
diamond, graphite, cryolite, selenium.diamond, graphite, cryolite, selenium.

4.  Due to depletion of mineral resources,Due to depletion of mineral resources,
researchers and scientists have found anresearchers and scientists have found an
alternative, they have prospected mineralsalternative, they have prospected minerals
resources in oceans. Many countries areresources in oceans. Many countries are
exploring and exploiting minerals from theexploring and exploiting minerals from the
oceans.oceans.
 we are going discuss what are thewe are going discuss what are the
minerals found in oceans and what are theminerals found in oceans and what are the
techniques used to mine minerals.techniques used to mine minerals.

5. TYPES OF MINERALS FOUND INTYPES OF MINERALS FOUND IN
OCEANSOCEANS
 VMS – volcanogenic massive sulfide ore deposits (metalVMS – volcanogenic massive sulfide ore deposits (metal
sulfide deposits)sulfide deposits)
 Copper, zinc, lead, gold, silverCopper, zinc, lead, gold, silver
 By-products include cobalt, sulfur, manganese,By-products include cobalt, sulfur, manganese,
barium, tin, cadmium, indium, telluriumbarium, tin, cadmium, indium, tellurium
 Formed by volcanic openings in ocean floorFormed by volcanic openings in ocean floor
 Superheated water + sulfur borne metals wells outSuperheated water + sulfur borne metals wells out
forming a cone (black smokers / fumeroles)forming a cone (black smokers / fumeroles)
 Deposits the above metalsDeposits the above metals
 Very hot highly acidic local conditions while activeVery hot highly acidic local conditions while active
 Petroleum deposits.Petroleum deposits.

6. PROSPECTINGPROSPECTING
 Acoustical devicesAcoustical devices
 Optical systemsOptical systems
 Navigation systemsNavigation systems
 Other devices and techniquesOther devices and techniques

7. Acoustic techniquesAcoustic techniques
1) Echo sounders operating at frequencies1) Echo sounders operating at frequencies
between 3 and 35 kHz provide seabedbetween 3 and 35 kHz provide seabed
and subsurface profiles.and subsurface profiles.
 A 3.5 kHz profiler can penetrate the upperA 3.5 kHz profiler can penetrate the upper
50m of sediments and log irregularities50m of sediments and log irregularities
such as subsurface intrusions and surfacesuch as subsurface intrusions and surface
extrusions of basalt.extrusions of basalt.

8.  Bottom towed side scan sonars provideBottom towed side scan sonars provide
information on obstacles and noduleinformation on obstacles and nodule
coverage. Echo sounders has sixteen narrowcoverage. Echo sounders has sixteen narrow
beams each with an angle of 1.66 degreebeams each with an angle of 1.66 degree
giving detailed topographic data.giving detailed topographic data.
2) GLORIA, is another system towed 50m2) GLORIA, is another system towed 50m
below sea surface, maps the ocean floor inbelow sea surface, maps the ocean floor in
swaths of 14,30 or 60km.swaths of 14,30 or 60km.

10. Optical systemsOptical systems
 To make reasonably accurate estimates ofTo make reasonably accurate estimates of
seabed minerals, analysts must haveseabed minerals, analysts must have
detailed sample information on their type,detailed sample information on their type,
volume, density of distribution, and thevolume, density of distribution, and the
amount of sediments covering them.amount of sediments covering them.
 Various large, still cameras with wide angleVarious large, still cameras with wide angle
lenses and a capacity for hundreds of framelenses and a capacity for hundreds of frame
are used, as are small flashlight camerasare used, as are small flashlight cameras
capable of only one shot. These units,capable of only one shot. These units,
combined with “boomerang” samplingcombined with “boomerang” sampling
devices, can take a photograph and thendevices, can take a photograph and then
return automatically to surface.return automatically to surface.

11. Other devices and techniquesOther devices and techniques
1)1) Bathysonde, provide vertical profileBathysonde, provide vertical profile
measurements of the water column’smeasurements of the water column’s
pressure, temperature and salinity.pressure, temperature and salinity.
2)2) Geologists use various grabs, dredgeGeologists use various grabs, dredge
buckets, and corers. Seabed grabbuckets, and corers. Seabed grab
samples taken at intervals can besamples taken at intervals can be
analysed by employing californium-252analysed by employing californium-252
radiation source. The process works byradiation source. The process works by
measuring gamma radiation given off bymeasuring gamma radiation given off by
seabed material after activation byseabed material after activation by
neutrons.neutrons.

12. Ocean mining methodsOcean mining methods

13.  Mining manganese nodulesMining manganese nodules

14. Mining polymetallic nodules usingMining polymetallic nodules using
continuous line bucket systemcontinuous line bucket system
 Continuous line bucket system (CLB)Continuous line bucket system (CLB)
consists of an 8 km cable on whichconsists of an 8 km cable on which
buckets were launched from the bow of abuckets were launched from the bow of a
former whaling ship.former whaling ship.
 In 1972 these CLB used to have only oneIn 1972 these CLB used to have only one
ship to collect the nodules, but only someship to collect the nodules, but only some
nodules were picked up, from the 1975nodules were picked up, from the 1975
they used two ship to cover large area.they used two ship to cover large area.

16. Hydraulic mining systemHydraulic mining system
 This system was conceptualized in 1988.This system was conceptualized in 1988.
 Its consisted of a semi-submersible surfaceIts consisted of a semi-submersible surface
platform, a catamaran type; a 4800 m rigid steelplatform, a catamaran type; a 4800 m rigid steel
pipe string, and a flexible hose, 600m long andpipe string, and a flexible hose, 600m long and
with a 38 m centimeter internal diameter,with a 38 m centimeter internal diameter,
connecting the bottom of the pipe string to aconnecting the bottom of the pipe string to a
dredge on the seabed.dredge on the seabed.
 This hose would form an arc, allowing theThis hose would form an arc, allowing the
dredge to deviate from the route followed by thedredge to deviate from the route followed by the
surface platform so as to avoid obstacles.surface platform so as to avoid obstacles.

17.  The self propelled dredge would be 18 mThe self propelled dredge would be 18 m
long, 15 m wide and 5 m high, weighinglong, 15 m wide and 5 m high, weighing
330t.330t.
 crawling on the bottom, it would collectcrawling on the bottom, it would collect
nodules and condition them for pumpingnodules and condition them for pumping
through the flexible hose.through the flexible hose.

19. Thank YouThank You