The idea of breathing underwater without
cumbersome compressed air tanks has been the
dream of science fiction writers for many years.
In George Lucas' movie "The Phantom Menace",
Obi-Wan whips out a little Jedi underwater
breathing apparatus and dives in. As things tend
to happen in our world, yesterday's science
fiction has turned into today's science fact due
to the dream of an Israeli inventor.
There are a number of limitations to the existing
compressed air tank underwater breathing method.
The first is the amount of time a diver can stay
underwater, which is due to the compressed air
tank capacity. Another limitation is the
dependence on compressed air refuelling
facilities near the diving site which are costly
to operate and are used to compress the gas into
the tanks which might be dangerous if not handled
properly. The final problem has to do with the
actual use of compressed air tanks underwater.
When these tanks are in use, they empty out, and
change the balance of the diver in the water.
Engineers have tried to overcome these
limitations for many years now. Nuclear
submarines and the international space station
use systems that generate Oxygen from water by
performing 'Electrolysis', which is a chemical
separation of oxygen from hydrogen. These systems
require very large amounts of energy to operate.
For this reason, smaller, diesel fuelled
submarines cannot use these systems and are
required to resurface to re-supply their air
tanks every so often. Divers can't even consider
carrying such large machines not to mention
supplying them with energy. To overcome this
limitation an Israeli inventor, Alon Bodner,
turned to fish.
Fish do not perform chemical separation of oxygen
from water; instead they use the dissolved air
that exists in the water in order to breathe. In
the ocean the wind, waves and underwater currents
help spread small amounts of air inside the
water. Studies have shown that in a depth of
200m. below the sea there is still about 1.5% of
dissolved air. This might not sound like much but
it is enough to allow both small and large fish
to breathe comfortably underwater. Bodner's idea
was to create an artificial system that will
mimic the way fish use the air in the water thus
allowing both smaller submarines and divers to
get rid of the large, cumbersome compressed air
tanks.
The system developed by Bodner uses a well-known
physical law called the "Henry Law" which
describes gas absorption in liquids. This law
states that the amount of gas that can be
dissolved in a liquid body is proportional to the
pressure on that liquid body. The law works in
both directions - lowering the pressure will
release more gas out of the liquid. This is done
by a centrifuge which rotates rapidly thus
creating under pressure inside a small sealed
chamber containing seawater. Rechargeable
batteries will power the system. Calculations
showed that a one-kilo Lithium battery could
provide a diver with about one hour of diving
time.
Bodner has already built and tested a laboratory
model and he is on the path to building a
full-scale prototype. Patents for the invention
have already been granted in Europe and a similar
one is currently pending examination in the U.S.
Meetings have already been held with most major
diving manufacturers as well as with the Israeli
Navy. Initial financial support for the project
has been given by Israel Ministry of Industry and
Commerce and Bodner is currently looking for
private investors to help complete his project.
If everything goes according to plan, in a few
years the new tankless breathing system will be
operational and will be attached to a diver in
the form of a vest that will enable him to stay
underwater for a period of many hours.
An Israeli Inventor has developed a breathing
apparatus that will allow breathing underwater
without the assistance of compressed air tanks.
This new invention will use the relatively small
amounts of air that already exist in water to
supply oxygen to both scuba divers and
submarines. The invention has already captured
the interest of most major diving manufacturers
as well as the Israeli Navy.