Improvements in the Process of Liquefying Gases and Apparatus therefor.
Year: 1898

page_text: Date of Application, 6th Oct., 1898
Complete Specification 1 eft 3rd July 1899-Accented 26th Aug 1899
PROVISIONAL SPECIFICATION.
Improvements in the Process of Liquefying Gases and Apparatus
therefor.
I, HERMANN GEORGES CHRISTIAN THOFEHRN, of 93, Rue Miromesnil, Paris, in
the Republic of France, Engineer, do hereby declare the nature of this invention
to be as follows:-
:―
This invention relates to improvements in the process and apparatus for liqui-
fying gases in a rapid manner in which a certain quantity of gas at a convenient
pressure is submitted to a series of expansions successively alternating with com-
pressions in apparatus arranged to absorb at each compression a part of the
heat contained in the gas. The temperature of the walls which extract the heat
from the gas is lowered in its turn by the non liquified particles of gas which at
their issue from the apparatus come into exterior contact with the walls.
It will be understood that as by this process the heat contained in the gas is
progressively removed, at each expansion, considerable lowerings of temperature
are caused which produce a rapid liquifaction of the gas. The apparatus con-
sists of a series of disks or plates of circular form diminishing in thickness
towards their centres and pierced at their centres with a small hole; these disks
are superposed the one above the other in the body of a cylinder and are kept at
a suitable distance from one another by collars or other suitable devices arranged
between them in the cylindrical body. These plates thus form flanges with spaces
between them in which the gas is successively expanded. The same construction
produces around the cylindrical exterior flanges, placed concentrically to the
interior ones, and similarly superposed. The top of the cylinder is dome shaped
and a pipe passes through the same for the entrance of the gas, the bottom is
formed by an inverted dome a slight space being left between its circumference
and the lower edge of the cylinder for the passage of the gas not liquified; this
lower dome is provided with a pipe for the outflow of the liquified gases. The
whole of the above described apparatus is contained in a drum or further cylinder,
between the interior of which and the surfaces of the exterior flanges of the
cylinder, the gas which has not been liquified passes. The drum is preferably
provided on its interior surface with a series of superposed crowns or flanges
which reach into the spaces between the exterior flanges of the inner cylinder
which arrangement gives a better contact of the non liquified gas with the
exterior flanges of the cylindrical body. The gas coming from a compressor
at a pressure of 200 pounds for example, enters into the upper dome of the
cylinder where it expands briskly with a fall in its temperature, in order to pass
into the first space between the plates it has to pass through the small hole in
the top most plate compressing itself in so doing, giving a certain production of
heat, which is carried to a certain degree by the conduction of the top plate,
which transmits this heat to the corresponding exterior flanges which is cooled
in its turn by the cold non liquified gas which passes by it. The quantity of
heat contained in the gas being thus diminished, the gas in passing to the second
space expands again and a further diminution of its temperature results; this

page_text: successive diminution of temperature increases as the gas passes to the successive
spaces and finally it issues in the form of drops into the lower dome receiver
where it is collected and drawn off, the particles of gas which have not become
liquified passing upwards between the cylinder and the drum pass out through
a pipe provided in the latter and return to the compressor.
Instead of an interior cylindrical body being provided the plates themselves
may be of such cross section so that when superposed they form the necessary
series of interposed spaces and exterior flanges.
It may be remarked that the exterior flanges may be in the form of spirals
or other suitable shapes the object being the same.
Dated this 6th day of October 1898.
HERBERT HADDAN & Co.,
Agents to Applicant.
Improvements in the Process of Liquefying Gases and Apparatus
therefor.
I, HERMANN GEORGES CHRISTIAN THOFEHRN, of 93, Rue Miromesnil, Paris, in
the Republic of France, 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:-
This invention relates to improvements in the process and apparatus for
liquefying gases in a rapid manner in which a certain quantity of gas at a con-
venient pressure, is submitted to a series of expansions successively alternating
with compressions in apparatus arranged to absorb at each compression a part
of the heat contained in the gas. The temperature of the walls which extract
the heat from the gas, is lowered in its turn by the non-liquefied particles of gas
which at their issue from the apparatus come into exterior contact with the
walls.
It will be understood that as by this process the heat contained in the gas is
progressively removed, at each expansion, considerable lowerings of temperature
are caused in such a manner that the liquefaction can be produced. starting with
an initial compression relatively small which would be impossible to obtain by
the simple expansion.
In the annexed drawing,
Fig. 1 is a longitudinal section of a form of construction of the apparatus.
Fig. 2 is a horizontal section on the line 1-2 of Fig. 1.
Fig. 3 shows on a larger scale a form of construction slightly different.
The apparatus consists of a series of disks, crowns or plates A of circular form,
pierced with a small hole a and superposed the one above the other in the body
of a cylinder B.
These disks can be lessened in thickness towards their centres as shown in the
drawing and the holes a can be in the axis of the apparatus. The said disks
by their superposition leave spaces between them, wherein the successive expan-
sions of the gas take place. The cylindrical body B is further provided on its
exterior with a series of flanges C placed concentrically to the interior disks,
and similarly superposed. The top D of the cylinder is dome shaped and a
pipe E passes through the same for the entrance of the gas, the bottom is formed
by an inverted dome F a slight space being left between its circumference, and

page_text: the lower edge of the cylinder, for the passage of the gas not liquefied; this
lower dome is provided with a pipe G for the outflow of the liquefied gases.
The whole of the above described apparatus is contained in a jacket or further
cylinder H, between the interior of which and the surfaces of the exterior flanges
of the cylinder, the gas which has not been liquefied passes. This drum is
preferably provided on its interior surface with a series of superposed crowns
or flanges which reach into the spaces between the exterior flanges of the
inner cylinder, which arrangement gives a better contact of the non-liquefied
gas with the exterior flanges of the cylindrical body. The gas coming from a
compressor at a pressure of 200 pounds for example, enters into the upper dome
of the cylinder where it expands briskly with a fall in its temperature, in order
to pass into the first space between the plates it has to pass through the small
hole in the topmost plate compressing itself in so doing, giving a certain produc-
tion of heat, which is carried off to a certain degree by the conduction of the
top plate, which transmits this heat to the corresponding exterior flange, which
is cooled in its turn by the cold non-liquefied gas which passes by it. The
quantity of heat contained in the gas being thus diminished, the gas in passing
to the second space expands again and a further diminution of its temperature
results; this successive diminution of temperature increases as the gas passes
to the successive spaces and finally it issues in the form of drops into the lower
dome receiver F where it is collected and drawn off through G the particles of
gas which have not become liquified passing upwards between the cylinder B
and the jacket H pass out through a pipe provided in the latter and return to
the compressor.
Instead of an interior cylindrical body being provided as in Figs. 1 and 2
the plates themselves may be of such cross section as L Fig. 3 so that when
superposed they form the necessary series of interposed spaces and exterior
flanges.
It may be remarked that the exterior flanges of Fig. 1, may be in the form of
spirals, or other suitable shapes their object being the same.
}
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed I declare that what
I claim is:
4
1. An improved process for liquefying gases in which a certain quantity of
gas given previously a convenient pressure is submitted to a series of alternate
expansions and compressions, produced by the passage of the gas in narrowed
openings and large chambers, alternately in such a manner that the heat pro-
duced at each compression will be absorbed by the walls which progressively
absorb the heat contained in the gas and rapidly reduce it to the liquefying
temperature from an initial pressure relatively small.
2. For the putting in practice of the process described in Claim 1, an apparatus
formed by superposing in a cylindrical body B a series of crowns or discs A
provided with small openings a and by superposing in a like manner other crowns
or flanges C which surround the cylindrical body B the whole being enveloped
in a jacket H in such a manner that the gas under pressure, coming from a
compressor and conveyed by a pipe to the upper part of the cylindrical body B,
first expands, then compresses itself whilst passing through the first opening a,
expands again in the space comprised between two crowns or disks A, com-
presses itself a second time in passing through the second opening and so on,
the gas losing at each compression a part of the heat produced which is absorbed
by the corresponding disk A, the temperature of the gas rapidly lowering itself
in the expansion which follows in such a manner that when arriving at the
lower part of the apparatus the gas expands freely for the last time, a part
becoming liquid and being drawn off, and the other part remaining gaseous
remounting in the apparatus at the exterior of the cylindrical body B in such a

page_text: manner as to cool the flanges C which in their turn absorb the heat of the
internal disks A and prevent them from becoming heated.
Dated this 3rd day of July 1899.
HERBERT HADDAN & Co.,
Agents to Applicant, 18, Buckingham Street, Strand, London.