The Wallace miner. [volume] (Wallace, Idaho) 1907-current, 1923-08-23
MAY USE LIQUID OXYGEN
IN NON GASEOUS MINES
NEW FORM OF EXPLOSIVE is
CHEAPER AND HAS 9TH
Err ADVANTAGES.

The use of liquid oxygen as an ex-
metal and other non gaseous mines
and in quarry and other outside blast
ing. is recommended by the United
State bureau of mines after a series
of tests. Preliminary experiments in
this novel explosive, conducted at the
bureaus experimental station at
Pittsburgh, indicate that it may be
used TO advantage where dusts and
gases are not present but is especial
~ useful elsewhere i'm lessening the
cost of blasting.
While liquid oxygen has not been
used in this country SO far for this
purpose, il is already widely used in
Mexican mines; has been employed in
large quantities in the upper Silesian
mines of Germany since the war; and
has been adapted to tunnel work, iron
mining subway and excavation work
in cities in that country It was used
not only in Germany but i'm the French
iron mines of Lorraine after the Ger
man seizure and applied by them also
to the destruction of French steel
plants. French officials of the Briey
iron district believe the explosive has
come to stay, and the bureau is con-
Quoting negotiations with Alaskan
companies for its adoption there
Made on Ground.
An advantage is that it can be pre-
pared on the job at low cost after the
erection of COMPRISING plants. when
viii make it of especial value in Alas
ka. AS liquid oxygen can be made at
the place of consumption. dangers
common to the transportation of 9TH
er explosives can he done away with
Low production cost. lessenlng the
cost per unit of material blasted, is
another advantage.
In the use of liquid oxygen explo-
sives there is practically no danger of
premature ignition. it was found The
danger of mishres too. is eliminated
by a wait of 30 on 40 minutes after
the fuse is lighted. when practically
all of the oxygen will have evaporat- !
ed. Another advantage is the elimin- |
alton of the danger of unexplodcd |
sticks in shoveling and subsequent
handling of coal or ore going out of !
the mine. Other sources of danger |
avoided are the handling and thaw-
ing processes such as are necessary |
with frozen dynamite and the hazard |
from lighting or fire when stored
Some Disadvantages.
But there are certain disadvantages |
in the use of this explosive. the bur
eau says. Because of it's rapid evap-
Grafton liquid oxygen must be used |
quickly and within definite time af- |
ter the hole is charged. thus limiting |
the number of holes that can be fired |
simultaneously although in Germany |
as many as 2S have been fired at once.
Its use virtually requires the installa-
tion of a liquidating plant at consid-
cradle first cost. and this plant must
be kept running regularly to obtain
low cost explosive, as the main cost
is in power used.
That the power of liquid oxygen as
an explosive is favorably comparable
with other explosives is shown in the
fact that 100000 pounds of liquid
oxygen are equal to $4,000 pounds
Of dynamite.
one of the interesting features of
he high development of this explosive
N Germany has been the designing of
small portable liquid oxygen making
plants to produce three liters an hour
such plants have been constructed to
move about on trucks making the
material much more available for the
mail operators.