AN IMPROVED MATERIAL FOR USE IN REFRIGERA- TING APPARATUS
Year: 1885

page_text: I, OLIVER IMRAY of N° 28 Southampton Buildings, Chancery Lane, in the
County of Middlesex, Fellow of the Institute of Patent Agents do hereby declare
the nature of my invention for "AN IMPROVED MATERIAL FOR USE IN REFRIGERA-
TING APPARATUS" to be as follows:-
According to this invention, instead of employing in a refrigerating apparatus
anhydrous sulphurous acid, SO³, a mixture thereof with carbonic anhydride, CO° is
used, the object being to render the refrigerating apparatus more effective and
economical, as by using this mixture a given apparatus worked with a given
power produces a greater amount of refrigeration than when sulphurous acid alone.
is used. Sulphurous acid can absorb carbonic anhydride to the extent of from
2 to 2 per cent of its weight, and the ebullition point of the mixture under atmo-
spheric pressure is at a temperature considerably below that of pure sulphurous
acid. The apparatus therefore that is employed to effect ebullition and compression,
produces an increased amount of cold, without proportional increase of the work
that has to be performed by it.
The carbonic anhydride may be mixed with the sulphurous acid before charging
the apparatus, or it may be added while the apparatus is at work.
ABEL & IMRAY,
Agents for the Applicant,
28, Southampton Buildings,
Chancery Lane, W.C.

page_text: f.
An Improved Material for Use in Refrigerating Apparatus.
I, OLIVER IMRAY of No 28 Southampton Buildings, Chancery Lane in the
County of Middlesex, Consulting Engineer and Patent Agent 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:-
"[
According to this invention, instead of employing in a refrigerating apparatus
anhydrous sulphurous acid, SO2, a mixture thereof with carbonic anhydride, CO',
is used, the object being to render the refrigerating apparatus more effective and
economical, as by using this mixture a given apparatus worked with a given power
produces a greater amount of refrigeration than when sulphurous acid alone is
used. Sulphurous acid can. absorb carbonic anhydride to the extent of from
2 to 2 per cent of its weight, and the ebullition point of the mixture under
atmospheric pressure is at a temperature considerably below that of pure
sulphurous acid. The apparatus therefore, that is employed to effect ebullition
and compression, produces an increased amount of cold, without proportional
increase of the work that has to be performed by it. The carbonic anhydride
may be mixed with the sulphurous acid before charging the apparatus, or it may
be added while the apparatus is at work.
or zero.
The accompanying diagrams illustrate graphically the effects of mixing carbonic
anhydride with the anhydrous sulphurous acid. In Fig. 1 the base line A B is
divided for every 5° C of temperature within a certain range on both sides of 0°
The vertical lines A C is divided for every half atmosphere of pressure
from 0 at A to 10 atmospheres at C. The curves, D, E, F, G represent the
relation of temperatures to pressures when sulphurous acid alone is used as shewn
by the curve D, when the sulphurous acid is saturated with carbonic anhydride as
shewn by G, and when it is impregnated with carbonic anhydride in intermediate
proportions, as shewn by the curves E and F. It will be seen that with pure
sulphurous acid, in the curve D, a pressure of one atmosphere, which determines the
point of ebullition, is at H corresponding to a temperature of about-11° or-12º,
whereas when the sulphurous acid is saturated with carbonic anhydride in the
curve G, the point of ebullition K is at a temperature of about 30°. In refri-
gerating apparatus operating by condensation and vaporisation, the cold produced
for a given volume of vapour is proportional to the pressure of the vapour. As
for instance, it appears at L that the pressure of the pure sulphurous acid vapour
at 15° is about 0.9'atm.; but, as appears at M, the pressure of the saturated acid
at 15° is about 14 atm, it may be concluded that for a given volume of vapour,
the quantity of cold produced when the saturated acid is used is to that produced
by the pure acid in about the proportion of 14 to 0.9, and therefore with a pump
of a certain capacity the production of cold is increased about 50 per cent when
the saturated acid is employed. On the other hand, the work required to produce
liquefaction does not follow the proportion of the pressure of the vapour acted on,
that is to say, of the cold produced, as will appear on examination of the diagram
Fig. 2. In this diagram the area of the curve between D1 and D2 represents the
work required for liquefaction of pure sulphurous acid, that between G' and G

page_text: represents the work required when the acid is saturated, and the other areas,
between E and E, and between F1 and F³, represent the work for intermediate
mixtures of carbonic anhydride with the acid. It will be found that the areas do
not quite follow the proportions of the pressures at equivalent temperatures but
that there is a gain of about 10 per cent in the cold produced by a given amount of
work, when instead of pure acid being used, acid saturated with carbonic anhydride
is employed.
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
In refrigerating apparatus in which anhydrous sulphurous acid is employed, the
admixture of carbonic anhydride therewith, substantially as and for the purpose
herein set forth.