IMPROVEMENTS IN THE PROCESS AND APPARATUS FOR PRODUCING COLD
Year: 1877

page_text: LETTERS PATENT to Hector Auguste Dufrené, of 10, Rue de la Fidélité,
Paris, in the Republic of France, and 4, South Street, Finsbury, London, Civil
Engineer and Patent Agent, for the Invention of "IMPROVEMENTS IN THE
PROCESS AND APPARATUS FOR PRODUCING COLD." A communication from
Monsieur Charles Tellier, of No. 99, Route de Versaille, Paris, in the Republic
of France.
Sealed the 27th October 1877, and dated the 3rd May 1877.
PROVISIONAL SPECIFICATION left by the said Hector Auguste Dufrené at
the Office of the Commissioners of Patents on the 3rd May 1877.
HECTOR AUGUSTE DUFRENÉ, of 10, Rue de la Fidélité, Paris, in the Republic of
France, and 4, South Street, Finsbury, London, Civil Engineer and Patent Agent.
"IMPROVEMENTS IN THE PROCESS AND APPARATUS FOR PRODUCING COLD." A com-
munication from Monsieur Charles Tellier, of No. 99, Route de Versaille, Paris, in
the Republic of France.
These improvements consist,-
Firstly. In employing trimethylamine, methylamine, ethylamine, or other ana-
logous volatile products at a low temperature, and soluble in water or other
liquid.
Secondly. In vaporizing one of these products for the purpose above described
either by means of the heat of escape steam from a steam engine, or by means of
any other suitable source of heat.
Thirdly. In so combining and arranging the apparatuses employed for this pur-
pose as to use only a limited quantity of the refrigerating body, and to produce a
current of air, gas, or uncongealable liquid carrying the cold to the place and for the
purpose desired.
For this purpose I cause the escape steam which is to be condensed, or, in short,
the source of heat which I wish to utilize, to pass into a tubular boiler, preferably
containing a solution of trimethylamine in water. The trimethylamine vapours,
after having been washed in a concentrated solution of trimethylamine, are forced

page_text: to pass through one or more worms, where they are liquified. The liquid product
is collected in a reservoir from whence it falls in a shower from top to bottom into
an apparatus or case containing a series of tubes enclosing a gas or an uncongealable
liquid moving from the bottom upwards. The trimethylamine is vaporized in
cooling the fluid in the tubes, which is then directed to cool the bodies, the tem-
perature of which it is wished to lower.
In order to utilize the trimethylamine vapours thus produced I can condense them
by means of a compressing pump, but I prefer to effect this condensation by means
of the water which contained these vapours at the commencement of the operation,
and from which the application of the heat separated them. For this purpose the
said water is cooled and conveyed to an apparatus or case into which also the trime-
thylamine vapours enter. The solution of these vapours in the water will be effected
under the action of a current of cold air passing in the tubes which traverse this
apparatus or condenser.
The first solution being thus reconstituted is discharged at the outlet into the
tubular steam boiler, heated by the lost vapours or otherwise, after having passed
through an apparatus where it is reheated in cooling the drained solution, which is
directed towards the condensing apparatus of the trimethylamine vapours. In this
manner any given quantity of this liquid may be used over and over again
indefinitely.
.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Hector Auguste Dufrené in the Great Seal Patent Office on the 2nd
November 1877.
HECTOR AUGUSTE DUFRENÉ, of 10, Rue de la Fidélité, Paris, in the Republic of
France, and 4, South Street, Finsbury, London, Civil Engineer and Patent Agent.
IMPROVEMENTS IN THE PROCESS AND APPARATUS FOR PRODUCING COLD." A com-
munication from Monsieur Charles Tellier, of No. 99, Route de Versaille, Paris, in
the Republic of France.
These improvements consist,-
Firstly. In employing trimethylamine, methylamine, ethylamine, or other ana-
logous volatile products which boil at a very low temperature (about 8° or 10°), and
which are soluble in water or other liquid.
Secondly. In vaporizing one of these products for the purpose above described
either by means of the heat of escape steam from a steam engine, or by means of
any other suitable source of heat.
Thirdly. In so combining and arranging the apparatuses employed for this pur-
pose as to use only a limited quantity of the refrigerating body, and to produce a
current of air, gas, or uncongealable liquid carrying the cold to the place and for the
purpose desired.
For this purpose I cause the escape steam which is to be condensed, or, in short,
the source of heat which I wish to utilize, to pass into a tubular boiler, preferably
containing a solution of trimethylamine in water. The trimethylamine vapours,
after having been washed in a concentrated solution of trimethylamine, are forced
to pass through one or more worms, where they are liquified. The liquid product
is collected in a reservoir, from whence it falls in a shower from top to bottom into
an apparatus or case containing a series of tubes enclosing a gas or an uncongealable
liquid moving from the bottom upwards. The tremethylamine is vaporized in
cooling the fluid in the tubes, which is then directed to cool the bodies, the tem-
perature of which it is wished to lower.
In order to utilize the trimethylamine vapours thus produced I can condense them
by means of a compressing pump, but I prefer to effect this condensation by means
of the water which contained these vapours at the commencement of the operation,

page_text: and from which the application of the heat separated them. For this purpose the
said water is cooled and conveyed to an apparatus or case into which also the trime-
thylamine vapours enter. The solution of these vapours in the water will be effected
under the action of a current of cold air passing in the tubes which traverse this
apparatus or condenser.
The first solution being thus reconstituted is discharged at the outlet into the
tubular steam boiler, heated by the lost vapours or otherwise, after having passed
through an apparatus where it is reheated in cooling the drained solution, which is
directed towards the condensing apparatus of the trimethylamine vapours. In this
manner any given quantity of this liquid may be used over and over again
indefinitely.
But to make the Invention communicated to me better understood, I will proceed
to describe the same by reference to the accompanying Drawings, in which Figure 1
shews one of the arrangements which may be employed.
A is a steam engine of any suitable construction. The escape steam which it pro-
duces is conducted into a condenser, shewn at B, and the form of which may vary;
and instead of being filled with water this condenser contains a solution of trime-
thylamine, obtained as herein-after described.
Under the effect of the heat which the condensed water steam gives off, the solu-
tion of trimethylamine is decomposed, and the trimethylamine itself being vaporized,
escapes by the conduit pipe b, b.
As gases which separate from their solutions always carry away some water
stearn, and as it is necessary in this case to have the trimethylamine as pure as
possible, the vapours which escape from the condenser B are rectified in the rectifier
C, which contains the richest solution of trimethylamine. For this purpose the
tube b, b, is inflected in such a manner that, being doubled round on itself, it may
be spread over the whole of the lower part of the rectifier C at z, z. Under these
conditions the trimethylamine vapour bubbles in the strong solution contained in
the rectifier C, and the vapours which escape therefrom through the tube c, c, will
be found to be sufficiently pure.
It should be remarked that it is requisite that this operation should be as com-
plete as possible, and it may therefore be necessary to add one or more rectifiers, or
to replace them by a rectifying column similar to those employed in the rectification
of alcohol.
To conclude with this part of the apparatus, the trimethylamine solution con-
stantly arrives by the tube a, b, travels over the whole of the rectifier, escapes by
the tube a, c, a, c, to run over the whole length of the condenser B, and finally
escapes by the tube ad, which conducts it into the float space D, which allows of
its expulsion.
It will be readily seen that under these conditions a water level is no longer
required, and that, just the spaces being filled with solution, the quantity of satu-
rated methylamine which arrives by the tube expels (in consequence of the general
falling back of the solution communicating itself to the condenser B) an equal part
of spent solution through d b.
The trimethylamine vapour which escapes by the tube c, c, enters a condenser E,
consisting of a worm or coil c, x, round which circulates a current of water entering
at e, a, and egressing at e, b.
From the effect of the light pressure which is produced by the ebullition of the
trimethylamine solution, a relative amount of cold is produced by the current of
water, herein-before described, around the worm or coil e, x, e, x, and the trimethy-
lamine is condensed; thus condensed, it escapes by the tube ec, which causes it to
pass through a worm or coil f, ff, placed in a receiver F, the object of which is
herein-after described. Finally, it is conducted by the tube f, a, to a float receiver G,
which, when it contains sufficient liquid, allows the solution to escape by the tube
g, a, and consequently it arrives in a large rectangular space H, which is nothing
but a refrigerator,

page_text: Before further describing this refrigerator I will describe the use of the float
space G.
The trimethylamine is condensed at about 10°. Running water having generally
a temperature of from 10° to 28°, according to the climate and seasons, a slight
pressure over that of the atmosphere will be necessary to effect its condensation,
and afterwards a pressure such as that already described in the condenser E. On
the other hand, as cold is to be produced, that is to say 12° to 15° below zero, it is
necessary to have a certain empty space in the apparatus in order that the trime-
thylamine may be vaporized. It is to allow these two phenomena to be produced
simultaneously that the float space G is employed, which puts a barrier between the
two of them.
The arrangement of the refrigerator allows of producing cold methodically, that is
to say, to cause the purest trimethylamine to arrive on the coldest surfaces in such
a manner that the energy of the vaporization remains constant.
The refrigerator consists of a rectangular cast-iron frame ha, ha, ha, ha, pro-
vided with a flange on each side, which allows of tightly closing it by means of two
plates of sheet iron held by a suitable number of tie pieces and nuts. Throughout its
height it is furnished with a certain number of tubes h, b, which are joined together
at their ends by elbows joining them together two and two, thus forming one com-
plete pipe.
If a current of uncongealable liquid (solution of chlorure of calcium or other
suitable solution) be thrown into this tube at its lower part by the tube g, c, this
current will rise through all the tubes, and finally egress by the tube g,d; mean-
while the liquified current of trimethylamine enters by the tube g, a; this liquid runs
into the trough ge, ge, which distributes it through the whole length of the
tubes h, h. The trimethylamine deposited by the points, with which the under side
of the tubes are furnished, runs over the periphery of the first tube, then that of the
second tube, and so on for the following tubes, and constantly vaporizing thereby,
constantly produces cold, but in so doing is impoverished, for the water which it
draws with it does not vaporize, on the contrary, it increases the solution in pro-
portion as it advances and paralyses the vaporization.
To withdraw all that part of the trimethylamine that may vaporize when this
liquid arrives at the lower part of the refrigerator H, it is discharged by the tube i a
into a tubular receiver I, which is in fact a vaporizer, in the tubes of which
circulates the current of chlorure of calciun which has been to convey the cold, and
in consequence is there at its highest temperature. Under the effect of this tem-
perature, proportionately raised, the last possible vapours of trimethylamine escape;
they are conducted by the tube i, b into the refrigerator H, where they are re-united
with those which are already formed there. But in order that the operation may
continue, the vapours must be removed as fast as they are formed. To effect this
they can be absorbed by a current of water.
It is preferable to abstract a current of spent solution from the boiler, and to
conduct this current into the apparatus shewn at J, in which the vapours may be
absorbed. This apparatus is exactly similar in its general arrangement to that
shewn at H, and is in free communication with the same by means of the vessel F
and its two tubes h and j, consequently the vapours which are formed in H arrive
freely in the apparatus J. To absorb them, the spent solution coming from the
vaporizing condenser B is conducted into the gutter ja, ja, and to the passage of
which I will berein-after refer. This gutter, perforated similar to the gutter
ge, g, e, with a multitude of holes, discharges over the length of the top tube jb the
solution from the first tube; it falls on to the second, and so on, thus offering a very
large surface for the absorption of the vapours which arrive from the apparatus H.
But to effect this absorption it is not sufficient merely to offer the absorbing surfaces
to the gas to be absorbed, it is necessary that the liquid should be cold, and moreover
that the heat produced by the condensation of the trimethylamine vapours should be
carried off, the absorption being in direct proportion to the temperature. To obtain

page_text: this double result the spent solution which escapes from the float vessel D is caused
to pass through the tube d, b, d, b, d, b, through an apparatus shewn at K, which may
be called a changer, and the action of which is herein-after described. At the
outlet k, a of this changer the solution escapes by the tube k, b, k, b, which conducts
it to a worm L, which, constantly surrounded with cold water, effects the cooling of
the said solution, which then enters the apparatus J at a temperature identical with
that of the water which was employed to cool it in the worm L.
With regard to the caloric which is disengaged during the condensation of the
trimethylamine vapours in the absorber J, it is carried off by a current of water,
which is caused to arrive by the cock j, c, and which, running through all the tubes
jb, jb, jb, carries off the caloric as fast as it is formed.
To assist the distribution of the liquids over the changer from H and J, they may
be coated with a light tissue of cotton netting.
Should water be scarce in the country where the apparatus is working, the water
which has been used in the absorber J may be used for the condensation in the con-
denser E, which is a very important consideration. Only slight excess of pressure
in the trimethylamine generating apparatus will result from this state of things, and
consequently it is always easy to set them up.
Referring again to the absorption, a portion of the vapours will have been able to
escape at the condensation. To avoid this inconvenience the vapours and the con-
denser liquid which has been used in the absorber J are caused to descend through
the tube jf, jf, which conducts the whole into M.
It will be easily seen that the whole arrives through the whole length of M by
the perforated tube jm, jm. The combination will thus be effected under the best
conditions, which are still more favoured by the current of cooling water, which,
entering at jc, first runs over the surface of M through the worm ma, ma, before
entering the tubes of the absorber J, and here the production of the solution which
was to be formed is finished.
As will be easily understood, it is necessary to take it back in such a manner
as to conduct it outside the absorber, and cause it to give back the trimethylamine,
which should again produce the freezing action, and thus render it permanent.
To obtain this latter result it must be reconducted to the vaporizing condenser.
For this purpose the tube me, me, me, me, passes from the absorbing vessel M to
the said vaporizing condenser. By following the course of the tube me, me, me, me,
it will be seen that instead of going direct to the vaporizer B, it is at first drawn
in by the pump N, which is necessary, since there is only a very low pressure in the
absorber J, and a higher pressure in the vaporizer B, and that moreover it is caused
to pass through the series of plates of the changer K; and I will now describe this
apparatus.
It has been seen that very hot liquid was sent out of the vaporizing condenser B,
and that, on the contrary, very cold liquid was discharged from M, and which should
be returned into the vaporizer B. It is then requisite to exchange the temperatures,
that is to say, to impart the heat to the liquid which is to enter the vaporizer B, and
the cold to the liquid which is to enter the absorber J, and it is for this purpose that
the changer K is employed. It consists simply of three plates of sheet iron united
together at their peripheries by one or two rows of rivets. This arrangement is
shewn in Figure 2.
The plate am is the exchange plate.
In the space R, R, circulates the liquid to be reheated, which may escape through
the tube rm; in the space S, S, on the other hand, comes the liquid which is to
impart the heat.
As will be easily seen by referring to K, the two liquids run in opposite direc-
tions, and consequently exchange their heat. The liquid which enters the rectifier C
by the tube ab, ab, is as hot as possible; and that which leaves by the tube
kb, kb, and enters the absorber J after having run through the worm L, is as cold
as possible.

page_text: It remains to describe some of the parts which are necessary to insure the
working of the apparatus. These consist of six pumps placed round the steam
engine A, viz. :-
1. An air pump, shewn at O.
2. Another similar air pump placed behind the pump O, and on a level with it, t
and is consequently not seen in the Drawing, but which I will call pump No. 2.
3. A chlorure of calcium pump P.
4. A feed pump N, moved by an excentric na, keyed on the shaft Q.
5. A pump similar to the chlorure pump, but placed at the opposite end of the
shaft this pump is not seen in the Drawing, but it shall be called pump No. 5.
6. Another feed pump similar to the pump N, not seen in the Drawing, called
pump No. 6.
I will now describe the working of these different pumps.
•
The pump O is for absorbing, by means of the tube o, o, o, o, the air which may
be brought by the water steam into the tubes of the condenser B, and therefore ]
insures the proper working of the same.
The pump No. 6, identical in its action to the pump N, takes, by means of the
tube t, t, t, the condensed water in the condenser B, and conducts it into the boiler,
which furnishes the steam to the cylinder of the engine A, and which may be placed
in any suitable position.
The pump No. 2, which is an air pump similar to the pump O, draws in through
the tube v all the air which may be in the apparatus J and H; it therefore allows
the trimethylamine which arrives there to evaporate at low pressure and carries off
at the same time the air which by chance might enter into the apparatus. A cook
placed at vw, allows of regulating this action, as will be understood. The pump :
No. 2 may be so fixed that it may be disconnected when required. As the air which
it draws in is charged with methylamine, it does not send it directly into the atmo-
sphere, but into a receiver containing water, and in which the trimethylamine may
be absorbed. This receiver is shewn at X. As will be easily seen, it is provided
with three tubes, one at x, which communicates with the pump No. 2; one at xa,
which communicates with the purifier; and one at at, which communicates with
the interior. Finally, a cock xm allows of drawing off the saturated liquid.
The working of the chlorure pump P has been herein-before described.
With regard to the pump No. 5, it draws up water from any suitable source, and
raises it into the upper reservoir to distribute it either around the condenser E, or
round the cooler L, and finally in the absorber J to be employed in the absorption.
The motive power furnished by the cylinder engine A needs no description; it is
used in the ordinary way.
The current of cooled chlorure of calcium which escapes through g,d may be
utilized for producing ice or cold.
The operation of the changer K will be readily understood.
The vapours which escape from H through h are very cold, but the trimethy-
lamine which runs through the worm ho, ho, is slightly warm, thus causing them
to circulate in opposite directions; the greatest amount of cold is extracted to carry
it back to H.
Having thus described the Invention communicated to me, and the best means
with which I am acquainted for carrying the same into effect, I wish it to be under-
stood that what is claimed and intended to be protected by the herein in part recited
Letters Patent is,―
Firstly. The employment of trimethylamine and analogous substances for the pro-
duction of cold, as herein-before described.
Secondly. The combination of the apparatus, herein-before described and shewn
in the accompanying Drawing, for producing cold by means of trimethylamine or
other analogous substance.
Thirdly. The employment of escape steam from a steam engine, or of any other

page_text: source of waste heat, for the production of cold (in combination with the employ-
ment of trimethylamine, and of the apparatuses herein-before described).
In witness whereof, I, the said Hector Auguste Dufrené, have hereto set
my hand and seal, this Thirty-first day of October, in the year of our Lord
One thousand eight hundred and seventy-seven.
H. A. DUFRENÉ (LB)