An Improved Refrigerating Machine for Ice Making and Cooling Purposes.
Year: 1891

page_text: Date of Application, 8th Sept. 1891-Accepted, 10th Oct.,
1891
COME LEIE SPECIFICATION.
An Improved Refrigerating Machine for Ice Making and Cooling
Purposes.
I, EDMUND TAYLOR of Victoria Parade, Geelong in the Colony of Victoria,
Contractor 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 that class of refrigerating machine for ice making and
cooling purposes wherein liquid ammonia is vapourised by a steam coil, and after
having been cooled and condensed is allowed to expand within a coil arranged
within a tank in which are deposited the ice moulds or other articles to be frozen
or cooled. The ammonia vapour, after having expanded and done its work, is
conducted into an. absorber containing a supply of spent liquor from the boiler,
whereby the strength of such spent liquor is increased. After having been restored
to its normal strength the ammonia liquor is returned to the boiler to be used over
again.
Instead, however, of employing a pump or pumps for returning such liquor I
provide a comparatively small cylinder or vessel into which such liquor can be run
from the absorber and from whence it can afterwards be conducted into the boiler,
vent pipes being employed for enabling, first the absorber and said receiving
cylinder to be put into communication with each other, and then for enabling said
cylinder and the boiler to be put in open communication with each other, the effect
being to allow the liquor to pass by gravity first from the absorber into said cylinder
and again to pass by gravity from said cylinder into the boiler, thus obviating the
necessity for employing a pump or pumps worked by power for effecting the purpose,
the result being to effect a considerable saving in working expenses.
My improved refrigerating machine for ice making and cooling purposes
comprises a boiler, a vapour-cooling tank and coil, a condenser, a freezing tank
and coil, an absorber or absorbers, an intermediate receiving cylinder, a temperature
exchanger, and a spent or thin liquor-cooling vessel and coil. The boiler just
mentioned consists of a vessel or cylinder containing a coiled pipe through which
steam can be passed. The upper end of this said vessel is connected with one end
of a coil or pair of coils in the vapour-cooling tank above referred to, as well as
with the intermediate receiving cylinder through the medium of a temperature
exchanger. The end or ends of the coil or coils in the cooling tank just referred
to is or are connected to a condenser whereby any ammonia vapour which passes
through said cooling tank is condensed, or has its temperature reduced to a
comparatively low point before it is conducted to a series of somewhat larger
pipes within the freezing or cooling tank, whose temperature it materially reduces
owing to the conversion of the ammonia liquor into vapour, drawing off much of
the latent heat of the liquid surrounding the coil or coils of pipe and the ice-moulds
in said cooling tank. The expanded vapour is then conducted into an absorber,
where it is passed through the body of spent or thin liquor which has been led into
it from the lower end of the boiler, thus re-charging said liquor and returning it fit
for use over again.
Now at this stage of the proceedings it has been usual heretofore to employ a
pump for forcing the strong liquor from the absorber back into the boiler. This
necessitates the expenditure of power and in practice causes a considerable loss of
ammonia by reason of the difficulty of avoiding leakage. I avoid this by employing
a comparatively small intermediate vessel or receiver into which the strong liquor
from the absorber is allowed to flow by gravity and (after the connection with the

page_text: absorber has been cut off) from whence it is allowed to pass, also by gravity, into
the boiler where it is again vapourised as above described.
According to one part of my invention I provide a pair of absorbers in lieu of
one only, as has hitherto usually been the case, and I connect said absorbers in
such a manner us that the liquor is drawn from about the middle of the first (that
is where it is strongest) and fed into the lower part of the second absorber (where
it is weakest) from whence it is drawn off at about the centre in the same way as
before, thus securing a supply of stronger liquor than would be possible were only
one absorber to be used.
Another part of my invention consists in providing a pair of boilers (instead of
one) and arranging them in a somewhat similar manner to the absorbers just
described, that is, so that the weaker liquor will be drawn off from the bottom of
one boiler, which will itself be fed from the bottom of the other boiler, the result
being that the stronger liquor will remain in the two boilers, the weakest being
drawn off and returned to the absorber, the result being advantageous in various
ways, partly because a larger quantity of ammonia vapour is expelled from the
liquor at each operation, and partly because the liquor fed into the absorber will
have a greater affinity for the ammonia vapour passing into it from the refrigerating
or cooling coils, thereby increasing the efficiency of the operation.
Another part of my invention relates to the employment of three or more
intermediate receiving vessels or injectors instead of one, said vessels being so
arranged as that the strong liquor from the absorber can be fed into one of said
vessels and from thence into a second, whilst the third one is being slowly emptied
into the boiler, the result being that by the time said third one is emptied the
second will be ready for use, whilst the first will have been filled with liquor
which can then be run into the third and so on, thus making the operation
a more continuous one than it would be if only one receiving vessel or injector
were employed and at the same time serving to prevent the liquor from the
absorber being heated to any appreciable extent before it is passed through the
temperature exchanger.
Referring to the accompanying drawings-
Fig. 1 is a diagrammatic sectional view illustrating the whole of my improved
refrigerating machine for ice making and cooling purposes, shewing it arranged and
constructed in the manner that I have found in practice to be most suitable for the
purpose.
Fig. 2 is a plan of the refrigerating or freezing tank in which the ice moulds or
other articles to be frozen or cooled are placed.
Figs. 3 and 4 are diagrammatic views illustrating the manner of employing the
intermediate receiver or cylinder which, according to my invention, is placed between
the absorber and the boiler and which enables the strong liquor to be fed from the
former into the latter without employing a pump.
Fig. 5 is a vertical central section illustrating the arrangement of a pair of
boilers, whereby I am enabled to more effectually extract or drive off the vapour
from the ammonia liquor, thus enabling weaker liquor to be fed into the absorber
than is the case when one boiler only is employed.
Fig. 6 is a sectional view illustrating the arrangement of a pair of absorbers
according to my invention, whilst
Fig. 7 is a diagrammatic view illustrating the arrangement of three receivers or
cylinders between the absorber and the boiler, whereby the feeding of strong liquor
to the latter can be carried on in a practically continuous manner.
Similar letters of reference indicate the same or corresponding parts in all the
figures.
A represents the boiler into which the ammonia liquor to be used in the manu-
facture of ice or for refrigerating purposes is placed, whilst a represents a coiled
pipe which is arranged within said boiler and is connected at one end to a steam
boiler B, so that said coil can be constantly kept full of steam, which after having
can lensed can pass out through the lower end of the coil a to waste. The vapour.

page_text: given off from the ammonia liquor in the boiler A passes along the two pipes c
into the coils c'e' in the ammonia dehydrator C. This consists of a tank or other
receptacle of any convenient shape and is so arranged as that a supply of cold
water can be allowed to flow continuously through it, thus condensing any aqueous
vapour and allowing it to flow back into the boiler A through the tubes c. c³ repre-
sents the overflow pipe from the condenser D through which a supply of cooling
water is led into said tank C. This condenser consists of an outer cylinder or
vessel which may be circular or any other convenient shape, and in which is placed
a hollow vessel & which is preferably made of a shape corresponding to the outer
one D and through which a number of comparatively small tubes d'd' are arranged
from top to bottom so that the cooling water which is fed into the condenser D is
free to pass through said tubes and thereby condense the ammonia within said inner
vessel or cylinder d. A thermometer d, a pressure gauge and height gauge (*
are fitted to said inner vessel to enable the temperature and pressure of the vapour
therein as well as the height of the condensed ammonia liquor to be readily ascer-
tained. d³ represents the inlet pipe whereby the supply of cooling water is fed into
the condenser D.
The pipe e (fitted with a regulating valve) serves to connect the lower end of
the inner vessel or cylinder d of the condenser D with the end of a coil e arranged
within the refrigerating or cooling tank E preferably as illustrated in Fig. 2, said
tank being made in two compartments one of which is adapted to receive said coil,
whilst the other is formed with a rack or partitions e, forming receptacles into
which the ice moulds or other articles to be cooled or frozen can be conveniently
fitted. The ammonia having expanded within this freezing or refrigerating coil e¹
is conducted through the pipe and discharged near the bottom of a vessel or
cylinder contained within the absorber F, where it is absorbed by the weak
or spent liquor (which has been fed into said absorber as hereinafter described) so
as to strengthen same ready for a fresh operation. This inner vessel or cylinder/'
is fitted with a series of tubes f³ extending through it from end to end. Cooling
water is fed into the absorber F through a pipe ", and circulating through its
tubes serves to lower the temperature of the ammonia within the vessel f¹ so
that the liquor will more readily absorb the vapour issuing from the pipe 2.
g represents a pipe whereby the strong liquor is drawn from the absorber F into
an intermediate vessel G which takes the place of the pump usually employed, as
will hereinafter be more particularly described.
H represents a cooling tank, through which the spent liquor from the boiler A
is caused to pass before entering the absorber F, the object being to reduce the
temperature of such weak liquor as much as possible in order that it may more
readily absorb the ammonia vapour passed into it in said absorber. Said cooling
vessel H contains a coil h, one of whose ends is connected through the medium of
a temperature exchanger I, hereinafter described with the boiler A, whilst its
other end is connected as shewn to the lower part of the inner vessel f¹ in the
absorber F. Cooling water is caused to flow through this vessel H from any
suitable source.
If found convenient the overflow from the absorber F can be
conveyed to the cooling tank H by means of pipe h¹ as illustrated in Fig. 1.
The temperature exchanger I consists of an outer cylinder or vessel containing
a coiled pipe i, through which the strong liquor from the intermediate receiver
passes to the boiler A, whilst the weak or spent liquor is passed from the bottom
of the boiler A up through the temperature exchanger I, outside the coil i, and
thence through the cooling coil into the lower part of the absorber F, the effect
of this arrangement being that the cool, strong liquor passing into the boiler
exchanges its temperature with the hot, weak liquor passing out of it, thus effecting
a saving both ways, as will be well understood.
I will now proceed to describe the manner of employing the intermediate receiver
or vessel G in order to feed the strong liquor from the absorber F into the boiler A
without the intervention of a pump. The regulating valve g³ and stop valves gª, 9ª,

page_text: (the latter being in the pressure equalising pipe 9 between the boiler A and the
vessel G) having been shut, the valve g' in the pipe g and the valve 9 in the vent
pipe 9' connecting the absorber F with the receiver G are opened, as illustrated in
Fig. 3, the effect being to equalise the pressure in said absorber and said receiver,
thus allowing the liquor in the former to flow by gravity into the latter, and
owing to the pipe 9 projecting up into the interior of the absorber F for a certain
distance the stronger liquor only will be drawn off. The valves o and g are then
closed, the valve g³ is then opened and afterwards the valves g³, as shewn in Fig. 4,
the regulating valve gl being by preference always allowed to remain open to a
sufficient extent to allow of the passage of the liquor from the intermediate
vessel G to the boiler A at such a rate as may be deemed most desirable. The
pressure in the boiler A and intermediate vessel G will now be equalised by
opening the valve 9 in the vent pipe 9, and the strong liquor in said intermediate
vessel will be allowed to flow by gravity through the temperature exchanger I
into said boiler A. By these means, as will be obvious, the employment of
a pump with its many attendant objections will be obviated. There is not
so much leakage of ammonia vapour, neither is there the expense of working
the pump.
Instead of employing a single boiler A as illustrated in Fig. 1 I prefer to employ
a pair of them as shown in Fig. 5 and to connect them together in such a way as
that the strong liquor from the absorber is fed into the upper part of the first
boiler A from the lower part of which the weaker liquor is drawn off through the
pipe a¹ into near the upper part of the second boiler A¹ from the lower part of which
the spent or weak liquor is forced through the pipe a² and temperature exchanger I
back to the absorber. By these means a much weaker liquor is obtained than is
the case when only one boiler is used, thus increasing the rapidity with which such
liquor takes up the ammonia vapour in the absorber, thereby materially increasing
the efficiency of the machine.
For a somewhat similar purpose I prefer to employ a pair of absorbers. F F' as
illustrated in Fig. 6. The weak or spent liquor after having passed through the
cooler H is fed into the lower part of the first absorber F from whence the stronger
liquor is drawn off through a pipe f* leading out of said first absorber at about the
centre of its height into the bottom of the second absorber F¹ from whence the
strongest liquor of all is drawn off through the pipe g into the intermediate vessel G
and from thence as required to the boiler as hereinbefore described.
f. f. represent as before the pipes whereby the vapour is fed into the absorbers F F1
from the refrigerating tank E, said pipes being provided with stop cocks as shewn
in order that the supply of vapour to either or both the absorbers may be controlled.
Water is caused to flow through both absorbers and can then be arranged to over-
flow as shewn into the cooling tank H, thus ensuring the absorbers being maintained
at as low a temperature as possible. f represents the pipe extending from the
lower end of the coil h in the cooler H to the bottom of the first absorber F
whilst fe represents a pipe which extends from the one just mentioned to the upper
part of said absorber, so that if preferred the weak or spent liquor can be injected
into the upper part of said absorber, the vapour in which it will absorb, whilst f'
represents a pipe provided with a valve which can be opened when only
one absorber is required to be used, the spent liquor then passing through said
pipe to the second absorber F' instead of passing through the first absorber
as will be well understood. The two absorbers are of course connected by a small
pressure equalising pipe f* in order that an equal pressure may be maintained in the
two vessels.
I sometimes employ two additional intermediate vessels G¹ G as shewn in Fig. 7
instead of a single vessel as shewn in Fig. 1. These additional vessels are connected
together and to the boiler A so that the strong liquor after having been run into
the uppermost vessel G as hereinbefore described with reference to the arrange-
ment shewn in Fig. 1 is conducted into either of the two lower ones G¹, G³, the

page_text: liquor in the second one of said lower vessels being meanwhile allowed to flow at
any required speed into said boiler A. By employing this arrangement the opera-
tion of feeding the boiler A with strong liquor is rendered practically continuous
because one of the lower vessels G' G' can be supplying liquor to the boiler whilst
the other one is being filled and vice versa. Moreover the uppermost vessel G will
be kept cooler than would otherwise be the case owing to its not being directly
connected to the boiler.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is-
1st. In a refrigerating machine for ice making and cooling purposes the inter-
position of an intermediate vessel (such as G) between the absorber and the boiler
substantially as and for the purposes herein described and explained and as illustrated
in Figs. 1, 3 and 4 of the accompanying drawings.
2nd. In a refrigerating machine for ice making and cooling purposes the com-
bination with an intermediate vessel (such as G) between the boiler and the
absorber of a temperature exchanger (such as I) also arranged between said
absorber and said boiler, substantially as and for the purposes herein described and
explained and as illustrated in the accompanying drawings.
3rd. In a refrigerating machine for ice making and cooling purposes the employ-
ment of a pair of boilers (such as A, A¹) having provision for the strong liquor
being fed into the upper part of the first one from the lower part of which the
weaker liquor is drawn off through a pipe (such as a') leading to the upper part of
the second one from whence the weakest liquor of all is drawn off near its lower
end, the whole being constructed and arranged substantially as and for the purposes
herein described and explained and as illustrated in Fig. 5 of the accompanying
drawings.
4th. In a refrigerating machine for ice making and cooling purposes a pair of
absorbers (such as F, F) into the first of which the spent or weak liquor is fed, and
from whence the stronger liquor is conducted from its upper part into the lower
part of the second absorber, the strong liquor being drawn off from near the upper
part of said second absorber to feed the boiler, the whole being constructed and
arranged substantially as and for the purposes herein described and explained, and
as illustrated in Fig. 6 of the accompanying drawings.
5th. In a refrigerating machine for ice making and cooling purposes the com-
bination with an absorber (such as F) of a set of three intermediate vessels (such
as G, G, G) arranged between and connected to said absorber and the ammonia
boiler, substantially as and for the purposes herein described and explained and as
illustrated in Fig. 7 of the accompanying drawings.
Dated this Third day of August One thousand eight hundred and ninety-one.