New Process of Utilising the Latent Heat of the Exhaust Steam of Steam Engines or Steam from other Sources, for Producing Liquid Ammonia in Absorption Refrigerating Machines.
Year: 1890

page_text: Date of Application, 17th Apr., 1890
Complete Specification Left, 1st May, 1890-Accepted, 5th July, 1890
PROVISIONAL SPECIFICATION.
New Process of Utilising the Latent Heat of the Exhaust Steam of
Steam Engines or Steam from other Sources, for Producing
Liquid Ammonia in Absorption Refrigerating Machines.
I, JOHANNES AUGUST OSENBRUCK, of Hemelingen near Bremen Germany,
Engineer do hereby declare the nature of this invention to be as follows:-
Careful and complete examinations of ammonia solutions in water as well as in
glycerine, have demonstrated that highly saturated solutions offer, as regards their
application in absorption refrigerating machines considerable advantages as compared
with weak solutions, and this not only as regards economy but also in the sense
of considerably increasing the effect of these machines, which are thus rendered
superior to other systems hitherto known.
The following table containing the results of my experiments made by me on a
large scale, will shew the correctness of the foregoing statement.

page_text: of water evaporated together with the ammonia or in other words, the weaker
the solution, the worse the distillate because in this case the latter contains more
water.
In distilling ammonia from rich solutions the temperature of the same remains
always below the boiling point of the water when the separation of the ammonia
is effected within reasonable limits, and pure anhydrous ammonia is in fact obtained.
It results therefrom that the indications of the above table for distilled ammonia
refer in the experiments 1 and 2 only to pure anyhydrous ammonia, while in the
experiments 3, 4, 5 and 6 they indicate ammonia more and more mixed with water.
The expenditure of heat for the ammonia obtained in these last four experiments is
really much higher than is shown in the table.
As indicated in the table the highly saturated ammonia solutions produce at a
proportionately low temperature of the heating vapor (100-5 Centigrade) very high
tensions of vapour (20 and 14 atmospheric pressures respectively) which are much
higher than is required in normal cooling water temperatures. Cooling water of
very high temperatures may therefore be used in these machines, the application of
which would not be possible in other machines.
The table shows furthermore, that highly saturated solutions require in separating
pure ammonia very small quantities of heat of low temperature; there is produced
for instance in experiment No. 1, 0,9687 kilogrammes ammonia per 1 kilogramme
exhaust steam of 100-5° Centigrade while the produce in the case of weak solutions is
reduced to 0,345 kilogrammes ammonia containing water, the temperature of the
heating steam increasing up to 167° Centigrade, that is to say a little higher than
7 atmospheric pressures of absolute tension.
It results therefore from the above, that the exhaust steam of steam engines or
generally of steam of 100° C. or some degrees more, affords an excellent and cheap
means for effecting the separation from highly saturated ammonia solutions of pure
ammonia vapours under so high a tension, that they can be easily liquefied even at a
high temperature of the cooling water.
In the accompanying drawing A is a distilling apparatus comprising a suitable
number (in this case four) of vertical wrought iron tubes, the interiors of which are
connected at top and bottom by smaller tubes. B is an air tight steam heating
chamber enclosing the steam pipes or conduits. The highly saturated ammonia
solution is supplied to the first heating pipe of the vessel A through the pipe cat the
height of the level of the liquid or a little below the same. The exhausted solution,
more or less freed from ammonia, leaves the apparatus A at the bottom of the last
heating pipe through the tube d. The ammonia freed by the exhaust steam from the
highly saturated solution in the distilling apparatus escapes through a pipe f into the
circulating portion of the refrigerating machine.
The exhaust steam of the steam engine C enters the heating chamber through the
pipe a near to the bottom of the last heating pipe of the apparatus A.
To utilise the exhaust steam as far as possible it is convenient instead of causing it
to act at once on all the heating pipes to compel it by means of the partitions B'
arranged in the heating chamber to flow from below upwards over each heating pipe
as indicated by the arrows. The water of condensation leaves the several compart-
ments of the heating chamber B through openings that discharge into a tube e while
the uncondensed steam escapes through the pipe 6 into the open air.
Dated this 17th day of April 1890.

page_text: COMPLETE SPECIFICATION.
New Process of Utilising the Latent Heat of the Exhaust Steam of
Steam Engines or Steam from other Sources, for Producing
Liquid Ammonia in Absorption Refrigerating Machines.
I, JOHANNES AUGUST (SENBRUCK, of Hemelingen near Bremen Germany,
Engineer, do hereby declare the nature in this invention and in what manner the
same is to he performed to be particularly described and ascertained in and by the
following statement :-
Careful and complete examinations of ammonia solutions in water as well as in
glycerine, have demonstrated that highly saturated solutions offer, as regards their
application in absorption refrigerating machines, considerable advantages as compared
with weak solutions, and this not only as regards economy but also in the sense of
considerably increasing the effect of these machines, which are thus rendered superior
to other systems hitherto known.
The following table containing the results of experiments made by me on a large
scale, will shew the correctness of the foregoing statement.

page_text: quantity of water evaporated together with the ammonia or in other words, the
weaker the solution the worse the distillate because in this case the latter contains
more water.
In distilling ammonia from rich solutions the temperature of the same remains
always below the boiling point of the water when the separation of the ammonia is
effected within reasonable limits, and pure anhydrous ammonia is in fact obtained.
It results therefrom that the indications of the above table for distilled ammonia
refer in the experiments 1 and 2 only to pure anhydrous ammonia, while in the
experiments 3, 4, 5 and 6 they indicate ammonia more and more mixed with water.
The expenditure of heat for the ammonia obtained in these last four experiments is
really much higher than is shown in the table.
As indicated in the table the highly saturated ammonia solutions produce at a
proportionately low temperature of the heating vapour (100-5 Centigrade) very high
tensions of vapour (20 and 14 atmospheric pressures respectively) which are much
higher than is required in normal cooling water temperatures.
Cooling water of very high temperature may therefore be used in these machines,
the application of which would not be possible in other machines.
The table shows furthermore, that highly saturated solutions require in separating
pure ammonia very small quantities of heat of low temperature; there is produced
for instance in experiment No. 1 0,9687 kilogrammes ammonia per 1 kilogramine
exbaust steam of 100-5° Centigrade while the produce in the case of weak solutions
is reduced to 0,345 kilogrammes ammonia containing water, the temperature of the
heating steam increasing up to 167° Centigrade, that is to say a little higher than
7 atmospheric pressures of absolute tension.
It results therefore from the above, that the exhaust steam of steam engines or
generally of steam of 100° C. or some degrees more, affords an excellent and cheap
means for effecting the separation from highly saturated ammonia solutions of pure
ammonia vapours under so high a tension, that they can be easily liquefied even at a
high temperature of the cooling water.
Referring to the drawings filed with my provisional specification A is a distilling
apparatus comprising a suitable number (in this case four) of vertical wrought iron
tubes, the interiors of which are connected at top and bottom by smaller tubes: B is
an air tight steam heating chamber enclosing the steam pipes or conduits. The highly
saturated ammonia solution is supplied to the first heating pipe of the vessel A through
the pipe cat the height of the level of the liquid or a little below the same. The
exhausted solution, more or less freed from ammonia, leaves the apparatus A at the
bottom of the last heating pipe through the tube d. The ammonia freed by the exhaust
steam from the highly saturated solution in the distilling apparatus escapes through a
pipe into the circulating portion of the refrigerating machine.
The exhaust steam of the steam engine Centers the heating chamber through the
pipe a near to the bottom of the last heating pipe of the apparatus A.
To utilize the exhaust steam as far as possible it is convenient instead of causing
it to act at once on all the heating pipes, to compel it by means of the partitions B¹
arranged in the heating chamber, to flow from below upwards over each heating
pipe as indicated by the arrows. The water of condensation leaves the several
compartments of the heating chamber B through openings that discharge into a
tube e while the uncondensed steam escapes through the pipe b into the open air.
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:
In ammonia absorption refrigerating machines working with solutions saturated at
so high a degree that the separation of a considerable part of the ammonia contained
therein is effected at a temperature below the boiling temperature of the water, the
combination of the exhaust steam conduit of one or more steam engines or of other
steam source with the steam heating chamber of the ammonia distilling apparatus

page_text: for the purpose of producing, by transmitting the latent heat disengaged in the
condensation of the exhaust steam, in the ammonia solution, the temperature by
which a correspondingly large part of the ammonia is separated from its solution in a
pure gaseous condition and at the same time under such a tension that the liquefaction
(condensation) of the ammonia is effected at a suitable and also at a high temperature
of the cooling water.
J. A. OSENBRUCK,
Per L. W.