IMPROVEMENTS IN THE PRODUCTION AND USE OF CARBONIC ACID FOR REFRIGERATING AND AERATING
Year: 1884

page_text: I JAMES HARRISON of 58 Gowrie Road, Battersea, in the county of Surrey,
Journalist, do hereby declare the nature of my Invention for IMPROVEMENTS IN
THE PRODUCTION AND USE OF CARBONIC ACID FOR REFRIGERATING AND
AERATING to be as follows:-
This Invention relates to the production of carbonic acid and its employment for
refrigerating and aerating either consecutively or separately. The gas is supplied
from a specially prepared material consisting of a mixture of carbonate and
bicarbonate of soda in such proportions as to form a plastic mass when warm, and
when cast in moulds to solidify at ordinary temperatures. This solid is placed in a
cylindrical vessel in proximity to or inside another similar vessel containing dilute
sulphuric acid. The two compartments are connected both above and below, so
that when the requisite pressure has been attained, and the upper communication
closed, the production of the gas becomes automatically regulated. When the
production is rapid the gas itself forces away the sulphuric acid, and when slow the
acid rises around the solid compound. The sesquicarbonate of soda, or trona, may
be substituted for the prepared material, and even the carbonate or bicarbonate
may be employed alone if placed in a perforated receptacle of lead, copper, glass, or
earthenware. When the carbonic acid is employed for refrigerating, the pressure
is allowed to increase until it reaches the point at which the gas is liquefied by its.
own pressure. The generating vessels are kept at such a temperature as prevents
liquefaction therein, and the gas passes into a third vessel which is kept cool, or it
is cooled on its way, becoming liquefied. A fourth vessel contains so much water
as is to be converted into ice, or the water may be placed in the third vessel, or
partly in both. The carbonic acid in resuming the gaseous state freezes the water,
converting it into snowy ice. After doing this work the gas is available for
aeration, for which purpose the efflux of the gas is regulated so that its pressure in
the fourth chamber is equal to that under which the aeration of the water or other
recipient in a fifth chamber is desired. When aerating alone is the object the
generating apparatus is placed in direct communication with the vessel containing
the liquid to be aerated, and the gas may at discretion be passed through a
purifying chamber supplied with a solution of carbonate of soda. The vessel
Perice fil

page_text: containing the liquid to be aerated is divided by diaphragms so perforated as to
ensure a large surface of exposure to the gas. When refrigeration is the chief
object, the used gas is allowed to escape into the air or into a gasometer at the
normal pressure, or it is utilised in converting the carbonate of soda into the
bicarbonate. When solid ice is wanted it is formed on the exterior of the third
vessel, and the fourth vessel is dispensed with, the gas, if wanted for aeration,
passing directly to the aerating chamber. When the gas is not wanted for areation
the third vessel may be partly charged with ether, naphtha, or mineral oil. The
refrigerating effect is also, when desired, communicated to a current of brine, air,
or other carrier of cold. The process is also applicable to the `generation of gas for
the aeration of bread.
Dated this twenty-second day of January 1884

page_text: I, JAMES HARRISON, of 58 Gowrie Road, Parish of Battersea, in the County of
Surrey, Journalist, do hereby declare the nature of my invention for IMPROVE-
MENTS IN THE PRODUCTION AND USE OF CARBONIC ACID FOR REFRIGERATING
AND AERATING 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 the combination of the processes of refrigerating and
aerating at one operation by means of carbonic acid produced under pressure by a
self-acting method without compressing pumps. The gas is supplied from a
specially prepared material consisting of a mixture of carbonate and bicarbonate of
soda in such proportions as to form a plastic mass when warm, and when cast in
moulds to solidify at ordinary temperatures. This solid is placed in a cylindrical
vessel in proximity to or inside another similar vessel containing dilute sulphuric
acid. The two compartments are connected both above and below, so that, when
the requisite pressure has been attained, and the upper communication closed, the
production of the gas becomes automatically regulated. When the production is
rapid, the gas itself forces away the sulphuric acid, and when slow the acid rises
around the solid compound. The sesquicarbonate of soda, or trona, may be
substituted for the prepared material, and even the carbonate or bicarbonate may
be employed alone if placed in a perforated receptacle of lead, copper, glass or
earthenware. The gas is first employed in refrigerating. The pressure is allowed
to increase until it reaches the point at which the gas is liquefied by its own
pressure. The generating vessels are kept at such a temperature as prevents
liquefaction therein, and the gas passes into a third vessel which is kept cool, or it
is cooled on its way, becoming liquefied. A fourth vessel contains so much water
[as is to be converted into ice, or the water may be placed in the third vessel, or
partly in both. The carbonic acid in resuming the gaseous state freezes the water,
converting it into snowy ice. When solid ice is wanted it is formed on the
exterior of the third vessel.
The refrigerating effect is also, when desired,
communicated to a current of brine, air, or other carrier of cold. The gas is now
available for aeration, the efflux of the gas being regulated so that its pressure in
the fourth chamber is equal to that under which the aeration of the water or other
recipient in a fifth chamber is desired. The fifth chamber is divided by diaphragms
so perforated as to ensure a large surface of exposure to the gas. The two parts of
which this invention consists are also capable of being used separately, the same
apparatus for the generation of the carbonic acid being applicable to either
refrigerating or aerating.
The mixture of carbonate and bicarbonate of soda is made by heating the
crystallised carbonate until it melts in its water of crystallisation. When the
crystals have lost some of their water of crystallisation by efflorescence, as is
usually the case with the commercial article, a little water is added. The melted
carbonate is then poured over the ordinary commercial bicarbonate, which is kept
stirred until the mixture becomes a thick paste or plastic mass. This is filled into
bottomless tin moulds, the mass being so thick that none runs out. The moulds Z
and Z are shown in Fig. 3. When the mass has become cold and set, it is pushed
out of the mould, Z which is is slightly tapering. Z is formed of two half cylinders
held together by clips at y, y. When filled and cooled, this mould is separated, and
the cylinder of. prepared material turned out. The resulting material is hereafter
simply designated "the carbonate."

page_text: I
1
The chambers for the reception of the sulphuric acid and the carbonate are
shown at A, fig 1. The external shell of this vessel is made of sufficient strength
to resist a working pressure of 750 lbs. on the square inch, and may be of either
cast steel or boiler plate. It is lined inside with lead or copper to resist the action
of sulphuric acid. The cover is removable, to admit of the removal of the charge of
carbonate and sulphuric acid, the connection with the tubes being broken at the points
a¹ and a². The form shown in the drawing is that which has the vessel containing
the carbonate inside the vessel containing the sulphuric acid. The chamber B is of
copper, open below, and is a fixture attached to the cover. The carbonate is
placed on a movable false bottom of copper, and is then pushed up into B. The
false bottom has indentations round its edge to admit of the upward passage of the
sulphuric acid. These indentations are deep enough to admit of their clearing the
studs c,-c, and when inserted it is turned until its projections rest on these studs.
The sulphuric acid is filled into the chamber A till it stands a quarter of an inch
above the studs. A small quantity of bicarbonate of soda is then thrown into the
acid, sufficient to generate enough carbonic acid to displace the air in the chamber.
The cover is then placed in position and screwed down. The packing is made
from blotting paper previously saturated with a solution of indiarubber and dried.
The surfaces with which it comes in contact are of course accurately faced. The
union a² is then screwed up, and caps placed on the ends of the tubes remaining in
position after the tube between a¹ and as has been removed. On the cover of A
there are two valves, v¹ and v2, actuated from without. The spindle of each valve
works through a screw. in the bridge b and through a stuffing box. A slight turn
is sufficient to raise the spile-shaped valve, which projects into a quarter-inch
aperture in the cover, so that it allows of the passage of a very slender stream of
gas. These valves are open until the cover is within half an inch of, being on its
seat; v is then closed and v² left open, so that no premature generation of gas can
take place while the cover is being fixed. The half-inch tubes t¹ t2 and t³ are
fixtures on the valve-boxes. The tube 3 is continued in a spiral coil in the
vessel C, which is an annulus through which a stream of cold water is passed, the
water entering at w¹, and passing out, heated by condensation of the gas, at w².
The carbonic acid gas condensed in C, passes into a receiver D through the tube t^,
which is a continuation of the spiral tube. The receiver is of equal strength with
the vessel A, and is fitted with a valve 3, similar to the valves on the top of A.
The receiver D is placed in a vessel of water d³ provided with an inlet passage w³
and an outlet w. The apparatus is set to work by opening the valve v¹, when the
sulphuric acid rises, in B and attacks the carbonate, the valve being also open.
The valve is kept open until the carbonic acid has had time to drive the air out
of the condensing tubes and receiver, which should be accomplished in about a
minute. The valve 3 is then closed. The water circulation is then set agoing
in C and d², slowly at first, until the pressure of the carbonic acid gas, as shown by
the gauge g, approaches the liquefying point, which is 50, atmospheres when the
condensing water passes off at 60° Fahrenheit. The flow of water is then
increased. The valve v2 is at the same time closed, and thenceforward the action
of the apparatus, so far as the generation of gas is concerned, is automatic. If the
flow of condensing water should, from neglect or accident be interrupted, and the
pressure of the gas should rise, the sulphuric acid is driven out of B; the action is
first retarded and then stopped. When the apparatus is first set to work the
temperature in A rises in consequence of the attraction of the sulphuric acid for
the water of crystallisation of the carbonate., This generation of heat is beneficial,
because it prevents the condensation of gas in the generator. The vessel A is
surrounded by water, but there need not necessarily be a continuous flow... It is
desirable to keep the water in d a few degrees above the condensing water running
from w² and 'w. So soon as the pressure reaches 50 atmospheres the operations of
ice-making and aerating are commenced.' The vessel E has been previously
two thirds filled with water to be frozen. As the carbonic acid is released from
pressure when it enters E, the vessel need not be stronger than those employed
de_0
315

page_text: in the ordinary aerating plant. The valve v³ is opened very gradually, and the
liquid passes through the tube into E, where it evaporates as it rises through the
water, thus cooling and freezing it. The expanded gas passes out of E by the
tube t to the gas-purifying vessel F which is half filled with ordinary crystallised
carbonate of soda, and thence through the tube 7 into the aerating vessel G. Inside
of this is the movable cage H, fitted with the diaphragms h; h, perforated all over.
Each perforation is made in the centre of a slight depression, with the burr of the
puncture downward, the tool with which the perforation is made producing an
indentation at the same time. The sides of the cage are also perforated except for
an inch below each of the diaphragms. The result is that not only is the water
brought in contact with the thin stream of gas passing through the perforations,
but there is an atmosphere of gas maintained over the water below each of the
diaphragms, rendering unnecessary any agitation of the water from the outside.
The water to be aerated is admitted at k¹, through which also passes any surplus
of carbonic acid, thus reaching the water in the tank, where some of it will be
saved. The carbonic acid from such an apparatus as is shown in the drawing is
sufficient for the aeration of several vessels similar to G, the number depending on
the degree of aeration required; or the aeration may be maintained exclusively
in G, the aerated water being continuously drawn off at k². When the operation is
drawing to a close, and the pressure falls below that which is required for aerating
the stopcock m¹ is closed, and the remainder of the gas is allowed to discharge itself
into the tank which supplies G with water; or the whole of the aerated water is
withdrawn from G, and the gas is allowed to expend its force on a fresh charge of
water in G preliminary to another operation. The water is forced into G and the
pressure regulated by any of the appliances known in the trade. These are not
shown in the drawing, as I propose no alteration in them. To get the ice from E,
its cover has to be removed, and the frame f. has to be lifted. The bottom of the
frame is a grating, sufficiently open to allow the gas to rise freely, and yet close
enough to retain the ice. To resume operations it is requisite to remove the cover
of the vessel A, to syphon off the liquid remaining in it, and to scoop out the solid
sulphate of soda (Glauber's salt.) The liquid syphoned off is added to the next
charge of sulphuric acid, which thus becomes diluted; but as the quantity of the
remainder liquid continues to increase, a diminishing proportion is added to each
succeeding charge, and a portion set aside for reconcentration. As it is not requisite
to restore it to its full strength, the concentration may be effected in a lead-lined
vessel at a temperature not much above that of boiling water. The action of the
apparatus is more regular with dilute than with strong acid; but as the dilution is
made in the course of a series of operations, it is as well to commence with a charge
of strong acid. No particular strength is requisite, and the dilution may go on
until the acid becomes insufficient to dissolve the whole of the charge of carbonate,
when a larger proportion of strong acid must be employed. When it is required to
form ice alone, the tube to is disconnected at the union a', and the carbonic acid is
allowed to run to waste under the ordinary atmospheric pressure, or it may be
conveyed into an ordinary gasometer; but the further use of the carbonic acid in
this way is beyond the scope of my invention. When it is required to make aerated
waters only, the tube t is connected to t¹ by a union, and with the purifying vessel
by a. The cap is then put on the end of the tube t³ at a², and the stopcock m³ is
shut. The carbonic acid then passes direct to the aerating vessels. The valve v
is closed so soon as the gauge shows that the required pressure has been reached,
and the generation of gas proceeds automatically as before.
An alternative mode of making ice is by forming it entirely on the exterior of
the vessel J, fig. 2. There are two ways of employing this vessel. If made of
equal strength with A, it takes the place of the third vessel D, the liquid carbonic.
acid collecting in it. If made of lighter material, as shown in the figure, it takes
the place of the vessel E. The vessel J is in the form of an annulus, two inches
wide at the top, and one inch at the bottom. It is contained in the open vessel d³, .
which is filled with the water to be frozen. The water occupies the whole of the

page_text: central space o³, surrounded by the annulus, and also a space one inch wide, o³,
outside of the annulus. When the operation is concluded, the supports of the
water vessel are withdrawn, and it soon falls away, leaving the ice attached to the
annulus; this also falls soon afterwards, the tapering form of the vessels favoring
its removal. When it is desired to cool brine, air, or other carrier of cold, without
the formation of ice, a current of the brine or air is circulated in the space o, the
current being introduced so as to pass through the central space, and to be with-
drawn from the exterior space. The vessels E and d³ are covered externally with
felt or other bad conductor of heat, this covering being removed from the vessel d³
when the ice is to be removed.
'
Separate apparatuses for making ice only, or for aerating only, require no special
description. An ice-making apparatus is precisely that which is shown in Fig. 1,
the whole of the aerating portion beyond the points al and a being dispensed with.
An apparatus for aerating'only remains when the portion of the combined apparatus
to the right of a and a is withdrawn. The vessel A with all its fittings remains
the same in either case, with this difference only that if the sole purpose be aerating,
the vessel A need only be of sufficient strength to withstand the pressure under
which the water or other liquid is required to be aerated.
☐ The processes may be varied in many ways, the principle remaining the same
throughout. The carbonate compound may be replaced by the sesquicarbonate of
soda, known commercially as trona, or even the ordinary carbonate or bicarbonate
alone, these being placed in a perforated receptacle of lead, copper, glass, or
earthenware and inserted in the chamber B in the same way that the prepared
carbonate is treated. The chambers A and B may be separate vessels of equal size,
connected above. by tubes and valves precisely similar to those already described,
the sulphuric acid being driven backwards and forwards through a connecting tube
below the level of the carbonate. The vessel D may be enlarged so as to contain
the whole of the liquified carbonic acid, to be kept in readiness when required, or
so as also to contain the water to be frozen. But I prefer the arrangements shown
in the drawings to any of these possible modifications.
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:
t
1. The formation and use of the prepared mixture of carbonate and bicarbonate
of soda as described, for the purposes of refrigerating and aerating, either conjointly
or separately.
2. The arrangement of the generator of carbonic acid, A and B for the purposes
of aerating and refrigerating whereby automatic action is secured, substantially as
described.
8. The formation of ice by the action of a stream of liquid carbonic acid passing
through the water and evaporating in contact therewith.
4. The particular arrangement for the formation of ice externally to the vessel
containing the evaporating carbonic acid, substantially as described.
5. The removable cage fitted with diaphragms perforated so as to ensure the
mixture of the carbonic acid gas with the liquid undergoing aeration, and to
ensure a large amount of surface contact between the gas and liquid, substantially
as described.
Dated this 21st inte of October 1881.