A New or Improved Process for Preparing, by the Aid of Gaseous Mixtures, Liquified Gas by Compression.
Year: 1895

page_text: Date of Application, 27th Apr., 1895-Accepted, 1st June, 1895
COMPLETE SPECIFICATION.
A New or Improved Process for Preparing, by the Aid of Gaseous
Mixtures, Liquified Gas by Compression.
I, FRIEDRICH KUHN, of Uetikon, Canton of Zurich, Switzerland; Chemist, 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 known methods hitherto in use for preparing, for example, carbonic acid
liquid by means of gas, or of sulphurous acid by means of gas from minerals, are
based upon the absorption of the gas to be liquified by a suitable solvent for the
extraction of a gaseous mixture, and upon the subsequent extraction of the said
gas of solutions or combinations thus prepared, either by means of heat, or by
exhaustion, before liquifying the said gas, previously purified and dried, by
compression and cooling.
According to my invention I only operate on dry gases, which consequently do
not attack the apparatus; in this process I utilize the cold produced by the
dilatation or expansion of the elements, not liquified, of gaseous mixtures
compressed and dry, for the re-cooling of the said mixtures with the view of
the separation of the liquifiable or condensable elements under form of liquid.
In carrying out my invention I proceed for example, by utilizing for the
purpose such an apparatus as is diagrammatically shown in the accompanying
drawing.
I take some gaseous mixtures such as the gas produced from the heating of
minerals and containing from 4 to 10 per cent. (in volume) of sulphurous acid, or
some gas (produced) from combustion containing carbonic acid, which gas or gases
is or are brought by a compressor to a suitable pressure after having been purified
and dried in any suitable manner.
After the gas or gases, thus compressed, have passed through a cooling apparatus,
and if that is necessary, a purifier, they are conducted into the apparatus represented
in the annexed drawing.
The compressed gases enter at A into the interior of the cylinder B, which is
externally provided with an insulating lagging, that is to say, a non-conductor of
beat. In this cylinder the said gases are sufficiently cooled by coming in contact
with one or several coils C so that some elements of the gaseous mixture become
liquified according to the temperature and pressure given, and accumulate at the
bottom of the cylinder where they are drawn off in a liquid state by the tap D into
other receptacles.
I can then facilitate the separation of the liquifiable elements of these gaseous
mixtures by the introduction of small quantities of materials remaining liquid at
low temperatures into the cylinder B, these materials being capable of dissolving
the liquifiable elements of the gaseous mixtures.
The non-liquifiable elements of the gaseous mixture pass into the air motor E to
which they furnish motive power by acting on the piston of the said motor, and
expand in it, in such manner as to become cooled sufficiently by their expansion
to escape by the exhaust passage and into the coil C, they are capable of
absorbing heat from the gaseous mixture first compressed, which is found in the
space B, and can consequently cool the said gaseous mixture.
The work furnished by the motor. E can be utilized to assist in working the
compressor or for exhausting at F (by a pump) the gas from the coil C and thus
to still lower the temperature.

page_text: 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. A new or improved process for preparing by the aid of gaseous mixtures,
liquified gas by compression, essentially characterized in that the cold produced by
dilatation or expansion of the non-liquifiable elements of the compressed gaseous
mixtures, is utilized for the recooling of the gaseous mixtures to separate the
liquifiable elements in a liquid state substantially as described.
2. A mode of carrying out the process characterized in Claim 1, in which in a
receiver B-in the upper part of which arrives the compressed gaseous liquid and
in the lower part of which the liquifiable elements are separated-is provided one
or several coils C through which, or by which the non-liquified elements of the
gaseous mixtures escape, after their dilatation or expansion in an air motor Ẹ with
the object of utilizing the non-liquified elements of the compressed gaseous mixture,
not only for re-cooling the gaseous mixture but also for the production of motive
power substantially as described.
Dated this 27th day of Anril 1805
BREWER & SON,
London and Leeds, Agents for Applicant.