Improvements in and Apparatus for the Production of Oxygen and Nitrogen from Atmospheric Air.
Year: 1892

page_text: Date of Application, 24th Oct., 1892
Complete Specification Left, 4th July, 1893-Accepted, 26th Aug., 1893
PROVISIONAL SPECIFICATION.
Improvements in and Apparatus for the Production of Oxygen and
Nitrogen from Atmospheric Air.
I LEONARD CHAPMAN of 232 Camberwell New Road in the County of Surrey
Engineer do hereby declare the nature of this invention to be as follows:-
The object of my invention is to provide means whereby oxygen and nitrogen
can be obtained from atmospheric air by a continuous process avoiding the waste of
oxygen which takes place when the operation is carried on intermittently as hitherto
and ensuring a product of greater purity. According to my invention I provide a
pair or a series of vessels or chambers in which the material by which oxygen is
absorbed and from which it is liberated is contained in a liquid form or suspended
in a liquid the said material after it has been peroxidized by absorbing oxygen from
the atmospheric air supplied thereto, being caused to pass into the vessel in which
the deoxidizing takes place and afterwards to pass back again to the preceding
vessel to again be peroxidized. The apparatus in which my invention may be
carried into practical effect consists in its simple form of two vessels which com-
municate with each other by passages in such manner that a circulation of the
material throughout the two vessels is obtained. The communications consist
preferably of pipes which ascend centrally from the bottom of the vessel and open
at top below the level of the liquid therein the lower ends of the pipes communicating
each with the other of the vessels.
An equal pressure above the material in the said vessels can be maintained by
means of suitably weighted outlet valves that of the peroxidizing vessel leading to
the open air or to the place where nitrogen or unabsorbed gas or gases'is or are to
be stored or employed and that of the deoxidizing vessel leading to the condenser
or separator and to the place of storage of the oxygen. A current or circulation of
the oxygen absorbent material is maintained throughout the two vessels that from
the peroxidizing vessel after having absorbed oxygen from the air which is caused
to pass therethrough descends the central pipe and passes into the deoxidizing
vessel in which the oxygen is withdrawn or liberated from it by the aid of steam
and then the material flows down the central pipe of the deoxidizing vessel and
passes back into the peroxidizing vessel to again absorb oxygen and this is con-
tinuous whilst the apparatus is at work. In order to control the speed of movement,
of the material I may use controlling valves to render the movement slower. To
hasten the movement I employ either an injector arrangement for air for the passage
between the upper part of the deoxidizing vessel and the lower part of the
peroxidizing vessel or an injector arrangement for steam for the passage between
the upper part of the peroxidizing and the lower part of the deoxidizing vessel or I
use both such injector arrangements together.
The air and steam used in the said injector arrangements can, in whole or in
part, be the air which is used for peroxidizing and the steam which is used for
deoxidizing.
The inlets for air and for steam may be provided with automatic pressure
regulating valves.
The vessels are heated by any suitable means such as by an external furnace or
furnaces and the oxygen absorbent material may be of any suitable character which
will pass from vessel to vessel as described. The two vessels may be heated to the
same or to different temperatures.
Although I have named two vessels in the foregoing description I may conduct

page_text: the process in a series of any suitable number having cominunications from the one
to the other for the purpose described.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, Agents.
COMPLETE SPECIFICATION.
Improvements in and Apparatus for the Production of Oxygen and
Nitrogen from Atmospheric Air.
I LEONARD CHAPMAN late of 232 Camberwell New Road now of 14 Flodden
Road, both in the County of Surrey Engineer do hereby declare the nature of
this invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement:-
The object of my invention is to provide means whereby oxygen and nitrogen
can be obtained from atmospheric air by a continuous process avoiding the waste of
oxygen which takes place when the operation is carried on intermittently and
ensuring a product of greater purity. According to my invention I provide a pair
or a series of vessels or chambers in which the material by which oxygen is
absorbed and from which it is liberated is contained in a liquid form or suspended
in a liquid the said material, after it has been peroxidized by absorbing oxygen
from the atmospheric air supplied thereto, being caused to pass into the vessel in
which the deoxidizing takes place and afterwards to pass back again to the
preceding vessel to again be peroxidized. The apparatus in which my invention
may be carried into practical effect consists in its simple form of two vessels which
communicate with each other by passages in such manner that a circulation of the
material throughout the two vessels is obtained. The communications consist
preferably of pipes which ascend centrally from the bottom of the vessel and open
at top below the level of the liquid therein the lower ends of the pipes communicating
each with the other of the vessels.
An equal pressure above the material in the said vessels can be maintained by
means of suitably weighted outlet valves (or their equivalents such as the columns
of water in the stand pipes as hereinafter described) that of the peroxidizing vessel
leading to the open air or to the place where nitrogen or unabsorbed gas or gases is
or are to be stored or employed.and that of the deoxidizing vessel leading to the
condenser or separator and to the place of storage of the oxygen. A current or
circulation of the oxygen absorbent material is maintained throughout the two
vessels that from the peroxidizing vessel after having absorbed oxygen from the air
which is caused to pass therethrough descends the central pipe and passes into the
deoxidizing vessel in which the oxygen is withdrawn or liberated from it by the aid
of steam and then the material flows down the central pipe of the deoxidizing vessel
and passes back into the peroxidizing vessel to again absorb oxygen and this is
continuous whilst the apparatus is at work. In order to control the speed of move-
ment of the material I may use controlling valves in either of the passages to render
the movement slower. To hasten the movement I employ either an injector
arrangement for air in the passage between the upper part of the deoxidizing vessel
and the lower part of the peroxidizing vessel or an injector arrangement for steam
in the passage between the upper part of the peroxidizing vessel and the lower part
of the deoxidizing vessel or I use both such injector arrangements together. The
air and steam used in the said injector arrangements can, in whole or in part, be the
air which is used for peroxidizing and the steam which is used for deoxidizing.
The inlets for air and for steam may be provided with automatic pressure regulating
valves. The vessels are heated by any suitable means such as by an external
furnace or furnaces and the oxygen absorbent material may be of any suitable
character which will pass from vessel to vessel as described. The two vessels, may
be heated to the same or to different temperatures.

page_text: I have illustrated in the accompanying drawing what I consider the best
arrangement for carrying out my invention in practice but I do not limit myself to
the precise details shewn. A shews the upper part of a gas producer from which the
gases generated pass by the outlet B to the combustion chamber C, meeting on
the way and mixing with heated air issuing from the passage D. The products of
combustion leave the chamber C by the apertures E and after circulating through
the furnace F pass out by the chimney G. In the furnace F two vessels H and I
are supported which vessels contain oxygen absorbing and yielding materials in a
liquid form or suspended in a liquid. These vessels are respectively provided with
inlet pipes J and K which deliver into annular passages formed at the bottom of
the vessels by the cone shaped bottoms and communicating with the interior of the
vessels by narrow openings or slits extending all round the bottom of each vessel as
shewn at and k. The said vessels are also provided with outlet pipes L and M
and circulating pipes N and O and the circulating pipe O is further provided with
a steam jet pipe P. The outlet pipes L and M are connected to the lower parts of
the stand pipes Q and R which communicate with one another by the pipe S. The
upper part of the stand pipe R is provided with a free ontlet to the atmosphere
or other required place through the pipe T while the upper part of the stand pipe Q
is closed to the atmosphere but communicates by means of the pipe U with the
inside of the gas holder V. The bent pipe W serves as a trap to prevent the
escape of gas but allow water of condensation of steam in the pipe U to escape.
Circulating water is admitted to the stand pipe Q at Y and passes through the
connecting pipe S to the stand pipe R, from which it flows off by the outlet. Z.
The vessels H and 1 are charged to above the level of the highest part of the
circulating tubes N and O with the oxygen absorbing and yielding material in a
liquid form or suspended in a liquid. At starting the stand pipes Q and Rare
charged with water until it escapes at the outlet Z. This water should be raised
to nearly the boiling point which may be done by admitting steam to the stand
pipes at their lowest parts through inlets provided for the purpose but not shown in
the drawing. Dry air is delivered through the pipe K to the annular passage at
the bottom of the vessel I from which it passes by the narrow opening up in a
finely divided state through the liquid oxygen absorbent material in the vessel I
which material it per-oxidizes. The excess of air, the nitrogen and the steam due
to the formation of manganate, pass off by the pipe M to the stand pipe R from
which after passing up through the column of water, the excess of air and the
nitrogen escape by the pipe T. Dry steam is supplied by the pipe J to the annular
passage at the bottom of the vessel H, from which it passes by the narrow opening j
up in a state of subdivision through the oxygen yielding material, which it decom-
poses or deoxidizes. The oxygen which is thus yielded together with the excess of
steam pass by the pipe L to the stand pipe Q, from which after traversing the
column of water, the oxygen passes by the pipe U to the gasholder V and from it
it can be withdrawn as required by the pipe X. Any steam or vapour condensing
in the pipe U, collects in the bent pipe W, from which it can flow off, but so long
as the difference in the heights of the columns of water d d in the bent pipe W is
not less than the difference between the levels of the water in the gasholder and
the gas holder basin, no escape of oxygen can take place. Sufficient cold water to
keep the water in the stand pipes Q and R at the proper temperature is admitted
at Y and escapes somewhat below the boiling point at Z. A large percentage of
the already low cost of producing oxygen by this process may be recovered by
utilizing this hot water for feeding steam boilers or for other purpose. The
difference in the heights of the columns of water in the stand pipes Q and R varies
with the pressure necessary to raise the gasholder V but the resistance to be over-
come by the gas issuing from the vessels H and I by the pipes L and M and
consequently the pressure within the vessels H and I remain equal under all
circumstances. A gentle circulation of the per-oxidized liquid absorbent down the
pipe O of the per-oxidizing vessel 1 to the bottom of the de-oxidizing vessel His
brought about by the action of a jet of dry steam admitted by the steam jet pipe P,

page_text: this jet of steam partly de-oxidizes the per-oxidized liquid it impels along the
pipe O, but the main de-oxidation is effected in the de-oxidizing vessel H by
the steam admitted by the pipe J. To replace the per-oxidized liquid thus with-
drawn from the per-oxidizing vessel I, de-oxidized liquid flows from the
de-oxidizing vessel H by the pipe N to the bottom of the per-oxidizing vessel I
where it is again per-oxidized by the air introduced by the pipe K, and so on
continuously. A part of the per-oxidizing air supply could also be employed as a
jet instead of or in addition to employing steam for causing the circulation of the
oxygen absorbing and yielding materials from one vessel to the other, but in that
casc air would be admitted by the pipe J and steam by the pipe K and per-
oxidation would take place in the vessel H, the outlet pipe of which would then
lead to the stand pipe open to the atmosphere, and the de-oxidation would be
effected in the vessel I, the outlet pipe of which would then be connected to the
stand pipe communicating with the gas holder. In the event of the temperature.of
the furnace being allowed greatly to exceed a dull red heat, a slight loss of caustic
potash might take place through volatilization, and to make good any such loss
arising from this or from other causes, I provide means for introducing caustic
potash in a liquid form, For this purpose an apparatus similar in construction to
an ordinary tallow or suet lubricator may be applied to the steam supply pipe.
Although I have described and shewn two vessels I may conduct the process in
& series of any suitable number having communications from the one to the other
for the purpose described. If the nitrogen be required it may be collected by the
pipe M being led to a gasholder or other place.
Manganate of potash with an addition of from 10 to 20% of its weight of caustic
potash is a very suitable material for the purposes of the process the dull red heat
at which the process is conducted rendering the materials sufficiently liquid to
circulate as described.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is―
1. In the production of oxygen and nitrogen or either of them from atmospheric
air the employment of an oxygen absorbing and yielding material in such a manner
that it is first per-oxidized in a vessel or vessels and then passes into another vessel
or vessels in which it yields up oxygen it then passing back to the peroxidizing
vessel or vessels in which it is again peroxidized and so on alternately during the
continuance of the process substantially as hereinbefore described.
2. In apparatus for the production of oxygen and nitrogen or either of them
from atmospheric air the combination of a peroxidizing vessel and a de-oxidizing
vessel connected so that oxygen absorbing and yielding material circulates in the
said vessels and is alternately peroxidized and deoxidized substantially as herein-
before described.
3. An arrangement and combination of parts constituting an apparatus for the
production of oxygen and nitrogen or either of them from atmospheric air
substantially as hereinbefore described and illustrated by the accompanying
drawings.
Dali. 4th dow of Tul.. 1009
J. H. JOHNSON & Co.,
Agents.