Improvements in Freezing Large Surfaces of Water, and in the Tanks and Apparatus Employed for that Purpose.
Year: 1893

page_text: The decision of the Comptroller-General, of the 11th day of April 1894, allowed,
under Section 18 of the Patents, &c. Act, 1883, an Amendment of this
Specification.
Date of Application, 13th June, 1893
Complete Specification Left, 30th Nov., 1893-Accepted, 30th Dec., 1893
PROVISIONAL SPECIFICATION.
Improvements in Freezing Large Surfaces of Water, and in the Tanks
and Apparatus Employed for that Purpose.
I, EDOUARD DE STOPPANI, of No. 111 Rue du Ranelagh, Paris, France,
Engineer, do hereby declare the nature of this invention to be as follows:-
My invention has reference to an improved mode of effecting the freezing of
strata of water of small depth and large extent of surface and in the tanks and
apparatus for that purpose.
I employ refrigerating tubes arranged in groups placed symetrically relatively to
the inlet and outlet branches for the refrigerating fluid; this arrangement has for
its object to reduce practically to zero the difference of the temperatures of the
two extreme tubes of contiguous groups, whether these tubes serve for the entrance
or the discharge of the refrigerating fluid.
These groups of tubes are all placed in a water-tight lead tank which is provided.
all round its sides with a deep channel having inclined sides, which channel has for
its object to maintain round the ice which is produced by the cold fluid circulating
through the tubes, a body of water which not being in contact with refrigerating
tubes, remains in a liquid state when all the water surrounding the tubes is frozen
solid.
By this means when the said body has been completely frozen, the water in the
said channel can be withdrawn through a discharge pipe, so as to leave an empty
space between the sides of the tank and the edge of the frozen sheet of water,
so that this as also the refrigerating tubes can expand and contract freely.
According to the arrangement which I employ by preference for carrying out my
invention, a tank of rectangular form, with the before mentioned deep channel
running round its sides, has the supply and discharge pipes for the refrigerating
fluid running along one of its longer sides, and from these pipes a number of groups
of tubes of zigzag form all lying in one and the same plane, extend over the
surface of the tank, at such a height as to be situated about midway between the
shallow layer of water contained in the same. These groups of tubes are by
preference so arranged that the inlet branches of two contiguous groups are placed
close together on the supply pipe, so that the refrigerating fluid in entering through
them, flows respectively to the right and to the left hand through the two groups,
and passes all through a discharge branch to the discharge pipe, so that the
discharge branches of two contiguous groups are also situated close together.
By this arrangement the difference of temperature between two contiguous
lengths of the zigzag refrigerating tubes is practically zero, the temperature being
caused to rise imperceptibly from the inlet to the outlet end of each group by the
absorption of heat from the water, and thus the sudden changes of temperature are
D

page_text: avoided which would occur if an inlet branch were placed next an outlet branch,
so that by this means a uniform congelation of the water and a smooth surface for
the ice is obtained. It will be evident that the same result would be obtained if
each group consisted only of a single U shaped tube, one limb of which would be
the inlet and the other the discharge branch.
The tank is by preference constructed as follows: A thick layer of concrete
having in the first instance been laid upon the excavated ground, including the
deep channels, a floor is laid upon this composed of a bad conductor of heat, such
as wood, brickwork &c., the deep channels and inclined sides thereof being also
covered with the same material.
'
This floor and lining is then covered with sheet lead well soldered at the joints to
form a water tight tank. The groups of refrigerating tubes are then laid above
the floor, being supported upon small blocks so as to be situated in about the
middle of the depth of water as described, the tubes being made to stop short of
the deep channel, which is provided with suitable outlet pipes for discharging the
water as described.
The inlet and outlet branches of the refrigerating pipes are not passed through
the sides of the tank, but are led in over the upper edge thereof and are then bent
down to the required depth.
By affording the refrigerating tubes and the ice surrounding the same perfect
freedom to expand and contract by means of the said surrounding channels, all
damage to the pipes or to the tank, and all rupture of the surface of the ice is
avoided.
Dated this 13th day of June 1893.
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION (AMENDED).
Improvements in Freezing Large Surfaces of Water, and in the Tanks
and Apparatus Employed for that Purpose.
I, EDOUARD DE STOPPANI, of No. 111 Rue du Ranelagh, Paris, France,
Engineer, 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 :-
My invention has reference to an improved mode of effecting the freezing of
strata of water of small depth and large extent of surface and in the tanks and
apparatus for that purpose.
In the Specification to my Patent No. 12256 of 1892 I described an arrangement
for this purpose in which groups of pipes laid upon the floor of a shallow tank had
refrigerating fluid passed through them so as to freeze the sheet of water with
which they were surrounded. According to my present improvements I employ
refrigerating tubes arranged in groups placed symetrically relatively to the inlet and
outlet branches for the refrigerating fluid; this arrangement to which I make no
claim has for its object to reduce practically to zero nil the difference of the
temperatures of the two extreme tubes of contiguous groups, whether these tubes
serve for the entrance or the discharge of the refrigerating fluid.
,
These groups of tubes are all placed in a watertight lead tank which is provided
all round its sides with a deep channel having inclined sides, which channel has for
its object to maintain round the ice which is produced by the cold fluid circulating
through the tubes, a body of water which, not being in contact with refrigerating
tubes, remains in a liquid state when all the water surrounding the tubes is frozen
solid.
By this means when the said body has been completely frozen, the water in the
"

page_text: said channel can be withdrawn through a discharge pipe, so as to leave an empty
space between the sides of the tank and the edge of the frozen sheet of water, so
that this as also the refrigerating tubes can expand and contract freely.
According to the arrangement which I employ by preference for carrying out my
invention, a tank of rectangular form, with the beforementioned deep channel
running round its sides, has the supply and discharge pipes for the refrigerating
fluid running along one of its longer sides, and from these pipes a number of groups
of tubes of zigzag form all lying in one and the same plane, extend over the surface
of the tank, at such a height as to be situated about midway between in the depth of
the shallow layer of water contained in the same. These groups of tubes are by
preference so arranged that the inlet branches of two contiguous groups are placed
close together on the supply pipe, so that the refrigerating fluid in entering through
them flows respectively to the right and to the left hand through the two groups,
and passes off through a discharge branch to the discharge pipe, so that the
discharge branches of two contiguous groups are also situated close together.
By this arrangement the difference of temperature between two contiguous
lengths of the zigzag refrigerating tubes is practically zero, nil the temperature
being caused to rise imperceptibly from the inlet to the outlet end of each group by
the absorption of heat from the water, and thus the sudden changes of temperature
are avoided which would occur if an inlet branch were placed next an outlet branch,
so that by this means a uniform congelation of the water and a smooth surface for
the ice is obtained. It will be evident that the same result would be obtained if
each group consisted only of a single U shaped tube, one limb of which would be
the inlet and the other the discharge branch.
Figures 1, 2 and 3 of the accompanying drawings shew respectively a longitudinal
section, a part transverse section, and a plan of a tank constructed in the above
described manner for freezing a sheet of water.
For allowing the free expansion and contraction of the submerged tubes during
the freezing, no matter what the degree of cold the fluid circulating through them
may have, 1 divide the whole of the tubes into a certain number of separate
groups A A A &c.; these groups are independent of each other, and are each
composed of a series of straight tubes, bent at their ends, so that each group
constitutes a serpentine tube in plan.
The refrigerating fluid (which may be of any known kind), that circulates in the
tubes, is distributed among the several groups at the points a¹ a² a³ at from the
supply pipe C, and issues from each group at the other ends 62 63 64 thereof into
the return pipe D. It will be seen that with this arrangement each group of pipes
is free to expand and contract during the freezing process, however low the
temperature of the refrigerating agent may be.
In order to obtain a perfectly smooth frozen sheet of water, I so arrange the
supply and discharge to and from the groups of tubes that the supply of fluid to two
contiguous groups takes place at two contiguous tubes at one end of two groups and
the discharge at the two contiguous tubes at the other end, that is to say, the supply
tube a' of the group A is contiguous to the supply tube a² of the group A', and the
discharge tube 63 of A' is contiguous to the discharge tube 6 of A2; and the same
with regard to a³ a. and-b³- By this means it will be seen that the difference of
temperature between any two tubes of all the groups will be inappreciable, and conse-
quently the water is not subject to sudden changes of temperature, such for instance
as would occur if the supply pipe of one group were placed next the discharge pipe
of another group.
With the arrangement described the temperature of the tubes
rises very gradually and equably in the direction from the supply end to the
discharge end of each group, so that throughout the whole tank there is, as it were, a
series of gradual undulations of temperature extending from the one end to the other.
Thus no part of the sheet of water being subject to sudden differences of temperature,
a very smooth process of congelation is obtained.
The uniform frozen surface would also be obtained by employing for each
serpentine group of tubes a series of U shaped tubes, one end of which is connected
.

page_text: to the supply and the other to the discharge, but to such tubes or groups of tubes I
make no claim.
The tank in which these refrigerating pipes are placed is constructed as follows.
On a layer of concrete X laid upon the excavated ground is formed a strong
floor F of wood, brickwork or other bad conductor of heat, the sides c of which are
carried up to a height slightly above that of the surface of the sheet of water to be
frozen, but to this construction make no claim.
All round this floor is formed a trench E sufficiently deep to prevent the water
contained therein from freezing while the water surrounding the tubes is being
frozen. The floor as also the trenches and the raised sides are covered with sheet
lead soldered together at the edges by melting with a blow pipe, so as to form a
perfectly watertight tank. The tubes are kept at a slight distance from the bottom
of the tank by means of small blocks, so as to be situated near the middle of the
depth of the water. They are kept a certain distance from the edges of the
trenches E, so as not to act refrigeratingly upon the water therein, so that a sheet
of ice is formed in which the tubes are embedded, and which is surrounded by
unfrozen water, the sheet, in freezing being thus perfectly free to expand without
exercising any pressure on the sides."
Openings are formed at ac in the trenches through which the water can be let
off from these after the sheet has been frozen, thus leaving the entire sheet together
with the tubes perfectly free to expand and contract.
When it is desired to form a fresh surface of ice on the sheet, this may be
readily effected by allowing sufficient water to enter the trenches again through
the openings to flood the sheet of ice with a thin layer of water, which is then
frozen.
By the above described means therefore any detrimental effects of expansion and
contraction upon the tank are avoided, and the cracking of the sheet of ice as also
the rupture or straining of the tubes and their connections is prevented.
The tubes a' a² &c. &c. branching from the supply and discharge tubes C
and D, are not led through the side of the tank, which might cause leakage, but
are made to pass over the upper edge thereof.
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 :-
1. In refrigerating apparatus for freezing sheets of water in tanks by means of
refrigerating tubes, such as herembefore referred to arranging the refrigerating
tubes in symmetrical groups in such manner that the contiguous tubes of two
adjacent groups are either both supply tubes or both discharge-tubes for the
refrigerating Huid and consequently-are maintained at the same temperature,
substantially as described.
2. In refrigerating apparatus for freezing sheets of water in tanks such as herem
referred to, arranging the tubes in serpentine form on plan, or as simple U-shaped
tubes, connected at one end to the supply and at the other end to the discharge,
substantially-as-described.
3. 1. In refrigerating tanks for freezing sheets of water, such as herein referred
to, forming a trench or recessed channel all round the edge of the tank for
preventing the water round such edge from freezing during the freezing of the
sheet of water, the said trench being situated beyond the ends of the refrigerating
tubes and being provided with means for emptying them it, substantially as
described.
4.-Constructing the tank referred to in the preceding claim of a bed of concrete
covered by a floor of wood or other bad conductor of heat, and lined with lead
substantially as described.
b. 2. In a refrigerating tanks such as are is referred to in the preceding claims,
supporting the refrigerating tubes at a certain distance from the bottom, of the
tank so that the frozen water surrounds the tubes on all sides, stopping short at a

page_text: slight distance beyond these, and surrounded by a belt of unfrozen water contained
in the trenches, so that the sheet of ice together with the tubes have has perfect
freedom to expand, substantially as described.
Dated this 29th day of November 1893.
ABEL & IMRAY,
Agents for the Applicant.