EP4296599A1

EP4296599A1 - Heat exchanger and cooling system

Info

Publication number: EP4296599A1
Application number: EP21718927.3A
Authority: EP
Inventors: Pedro TORIBIO QUERO
Original assignee: Cruz Pedrosa Agustin; Garcia Gomez Lorenzo; Proyectos Y Montajes Industriales Menxi Srl
Current assignee: Cruz Pedrosa Agustin; Garcia Gomez Lorenzo; Proyectos Y Montajes Industriales Menxi Srl
Priority date: 2021-02-16
Filing date: 2021-02-16
Publication date: 2023-12-27
Also published as: WO2022175566A1

Abstract

Heat exchanger (1) for fluids, comprising at least two sets of pipes (10), each set of pipes (10) including an internal pipe (11), an intermediate pipe (12) and an external pipe (13), concentric to each other and forming between them spaces for the longitudinal circulation of fluids, wherein the intermediate pipes (12) are connected in series by means of curved pipes (20), wherein each set of pipes (10) comprises an inner connecting conduit (31) that fluidically connects one end of the internal pipe (11) with an element external to the set of pipes (10) itself, an intermediate connecting conduit (32) that fluidically connects the other end of the internal pipe (11) with the adjacent end of the corresponding external pipe (13), and an outer connecting conduit (33) that fluidically connects the other end of the external pipe (13) with another element external to the set of pipes (10) itself.

Description

Field of the invention

The present invention relates to a heat exchanger for fluids, particularly suitable for fluids of a foodstuff with low thermal transmittance, such as for example paste from olives. Another aspect of the invention relates to a refrigeration system incorporating such a heat exchanger.

Background of the invention

Heat exchangers for the heat treatment of fluids are known in the prior art. For example, document DE8332947U1 relates to a heat exchanger for the heat treatment of grape puree, grape must, wine, and the like. The type of heat exchanger may comprise several heat exchange assemblies, arranged in parallel, which comprise internal pipes for the circulation of the fluid to be treated and concentric external pipes for the circulation of a heat exchange medium, which is generally a coolant. At the same time, it has curved pipes that connect one end of the internal pipes of one assembly to the other, as well as ducts that connect the external pipes transversely to each other. This type of heat exchanger is suitable for food products with high thermal transmittance, such as grape products. However, to achieve effective heat exchange in products with low heat transmittance, the length of the heat exchanger required to achieve adequate cooling is either impractical, or the tubes are too wide and cooling is inadequate.
In addition, there are heat exchangers with both internal and external tubes for the circulation of the heating or cooling medium, such as that disclosed in document RU95087U1 . However, these are only designed to have a single heat exchange assembly, so that to achieve effective heat exchange in products with low thermal transmittance, their length also ends up being excessive.
It is therefore desirable to provide an alternative to the state of the art by proposing a heat exchanger which allows effective cooling of foodstuffs with low thermal transmittance and which has practicable dimensions.

Description of the Invention

The present invention provides a heat exchanger for fluids, particularly suitable for fluids of a food nature with low thermal transmittance, where fluid is understood as any material that can circulate through pipes, whether in the form of a liquid, gas, dough, paste, granules, etc.
The heat exchanger claimed comprises at least two sets of pipes, each set of pipes including an internal pipe, an intermediate pipe and an external pipe, concentric to each other and forming closed spaces between them for the longitudinal circulation of fluids. The sets of pipes are positioned substantially parallel to each other, and the intermediate pipes are connected in series by means of curved pipes, so that they form a circuit for the circulation of the fluid to be treated. For this purpose, one of the intermediate pipes comprises an end that is open to the outside of the heat exchanger through which the fluid to be treated can be introduced, and another of the intermediate pipes comprises an open end through which the fluid to be treated can be extracted.
This heat exchanger is characterised in that each set of pipes comprises:

an inner connecting conduit that fluidically connects one end of the internal pipe itself to an element external to the set of pipes,
an intermediate connecting conduit that fluidically connects the other end of the internal pipe itself to the adjacent end of the external pipe of the same set of pipes, and
an outer connecting conduit that fluidically connects the other end of the external pipe itself to another element outside the external pipe.

Thanks to this configuration of connecting conduits, suitable for connecting the internal pipes with the external pipes of the different set, a heat exchanger is obtained with a circuit for the circulation of a heat exchange medium (which will usually be a coolant with which to cool the fluid to be treated) that passes both inside and outside the fluid to be treated and which can have the necessary length to achieve the required heat exchange between the two fluids without its dimensions being impracticable.
For example, in the case that the heat exchanger includes two sets of pipes, one of these would have an inner connecting conduit that connects one of the ends of its internal pipe to an external element (such as the fluid outlet of a pump that introduces the heat exchange medium) and an outer connecting conduit that fluidically connects the other end of the external pipe to the inner connecting conduit of the second set of pipes. And finally, the outer connecting conduit of this second set of pipes would connect to another external element (such as the fluid inlet of the pump).
As can be deduced, the fluid to be treated will only circulate through the intermediate pipes, while the heat exchange medium will circulate inside the internal pipe and through the space available between the external pipe and the intermediate pipe. Preferably, the direction of circulation of the heat exchange medium should be such that, in the same set of pipes, it passes through the internal pipe first.
Preferably, the curved pipes include removable means of connection to the intermediate pipes, so that they can be easily removed for cleaning the circulation circuit of the fluid to be treated. In a preferred embodiment, the intermediate pipes protrude at both ends with respect to the internal and external pipes, which also facilitates the implementation of the removable curved pipes.
Both the curved pipes and the intermediate and internal pipes are preferably dimensioned to have a cross-section for a flow of at least 3,000 litres or kilograms per hour. For the connecting conduits, preferably pipes with standardised nominal diameters, e.g. 40 mm, 65 mm or 80 mm as per EN ISO 6708, are used.
In a preferred embodiment, the internal pipes comprise a transverse closing wall at their ends, while the inner connecting conduits and intermediate connecting conduits are longitudinally connected to these closing walls. In addition, said conduits may have curved sections for changes of direction, instead of right angles. As a result thereof, the circulation of the heat exchange medium is more fluid. In an even more preferred embodiment, the intermediate connecting conduits are connected to the external pipes from the outside thereof and in a radial direction, so that the heat exchange medium encounters less resistance as it passes. To this end, the internal pipes preferably protrude at both ends from the external pipes, so that the inner connecting conduits and the intermediate connecting conduits only have to pass through the intermediate pipes.
Preferably, the heat exchanger comprises three sets of pipes. In this case, it has a first set of pipes with an inner connecting conduit connecting one end of its internal pipe to an external element (such as the fluid outlet of a pump introducing the heat exchange medium). This first set of pipes also has an outer connecting conduit that fluidically connects the other end of the external pipe itself to the inner connecting conduit of a second set of pipes. This second set of pipes, in turn, comprises an outer connecting pipe fluidically connected to the inner connecting conduit of a third set of pipes. And finally, the outer connecting conduit of this third set of pipes is connected to another element external to it (such as, for example, the fluid inlet of said pump). In a preferred embodiment, two of the pipe sets are at the same height and a third one is above the first two. This makes it easier to house all the components of the heat exchanger in a cylinder that serves as a cover, which facilitates transport. This cover can also be fitted with legs for support on the ground and connection means for lifting, e.g. with a crane. The inlet and outlet of the heat exchange medium are preferably located at the top of the cover.
A further objective of the present invention is a refrigeration system comprising any of the above-described embodiments of the heat exchanger of the present invention. This cooling system may also have a pump for pumping the fluid to be cooled through the intermediate pipes of the heat exchanger, as well as a pump for pumping the coolant through the circuit provided for this purpose in the heat exchanger.
Preferably, the cooling system includes means for the user to select the working or cooling temperature, which preferably may be between -8°C and 8°C.

Brief description of the figures

For a better understanding of what has been explained above, the following drawings show an embodiment of the invention, schematically and only as a non-limiting example.

Figure 1.- Illustration of a side view of a first preferred embodiment of this heat exchanger.
Figure 2.- Illustration of a plan view of section A-A of figure 1.
Figure 3.- Illustration of a side view of a second preferred embodiment of this heat exchanger.
Figure 4.- Illustration of a plan view of section B-B of figure 3.
Figure 5.- Illustration of a side view of a third preferred embodiment of this heat exchanger.
Figure 6.- Illustration of a front view of the third preferred embodiment of this heat exchanger.

Description of preferred embodiments

Some preferred embodiments of this heat exchanger are described below, with reference to figures 1 to 6.
Figures 1 and 2 show a first embodiment of the heat exchanger, which comprises a first and a second set of pipes (10, 10'), each including an internal pipe (11, 11'), an intermediate pipe (12, 12'), and an external pipe (13 13'), concentric to each other. As can be seen in the section of figure 2, the two intermediate pipes (12, 12') are connected in series by means of a curved pipe (20), and both comprise an open end (131, 131') through which the fluid to be treated can be introduced and extracted.
In turn, the first set of pipes (10) comprises:

an inner connecting conduit (31) that fluidically connects one end of its internal pipe (11) to an inlet port (311) of the heat exchange medium,
an intermediate connecting conduit (32) that fluidically connects the other end of its internal pipe (11) to the adjacent end of its external pipe (13); and
an outer connecting conduit (33) that fluidically connects the other end of its external pipe (13) to the inner connecting conduit (31') of the second set of pipes (10').

While the second set of pipes (10') comprises:

said inner connecting conduit (31') that fluidically connects one end of its internal pipe (11') to the outer connecting conduit (33) of the first set of pipes (10);
an intermediate connecting conduit (32) that fluidically connects the other end of its internal pipe (11) to the adjacent end of its external pipe (13); and
an outer connecting conduit (33') that fluidically connects the other end of its external pipe (13') to an outlet port (331') of the heat exchange medium.

As indicated by the small arrows in figures 1 and 2, the direction of flow of the heat exchange medium in the same set of pipes (10) is such that it passes first through the internal pipe (11, 11') and then through the external pipe (13, 13').
Figure 2 also shows the removable connecting means (21) of the curved pipes (20) to the intermediate pipes (12, 12'). As can be seen, the internal pipes (11, 11') protrude at both ends with respect to the external pipes (13, 13'), so that the inner connecting conduits (31, 31') and the intermediate connecting conduits (32, 32') only pass through the intermediate pipes (12, 12').
As shown in figure 2, the inner connecting conduits (31, 31') and the intermediate connecting conduits (32, 32') are connected longitudinally in the middle to the internal pipes (11, 11'), i.e. at the transversal walls of their ends. In turn, the intermediate connecting conduits (32, 32') are connected to the external pipes (13, 13') from the outside thereof and in a radial direction. In this way there is less resistance to the flow of the heat exchange medium.
Figures 3 and 4 show a second embodiment of the heat exchanger, which comprises three sets of pipes (10). In this case, it also has an intermediate set of pipes (10") with an inner connecting conduit (31") connecting one end of its internal pipe (not visible in the figures) to the outlet conduit (33) of the first set of pipes (10). This intermediate set of pipes (10") also has an intermediate connecting conduit (32") connecting the other end of its internal pipe to the adjacent end of its external pipe (13"), as well as an external connecting conduit (33") fluidically connecting the other end of the external pipe itself (13") to the internal connecting conduit (not visible in figures 3 and 4) of the second set of pipes (10').
In this preferred embodiment of figures 3 and 4, the inlet port (311) and the outlet port (331') of the heat exchange medium are horizontal, but could be disposed vertically at the top of the heat exchanger. Likewise, two of the sets of pipes (10, 10') are in the same vertical plane, but could also be in the same horizontal plane, i.e. at the same height. In this way, it is easier to house all the components of the heat exchanger in a cylinder that acts as a cover (40) to facilitate transport, as shown in the embodiment of figures 5 and 6. The cover (40) of the latter embodiment also has legs (41) for its support on the ground and connection means (42) for lifting it.

Claims

Heat exchanger (1) for fluids, comprising at least two sets of pipes (10), each set of pipes (10) including an internal pipe (11), an intermediate pipe (12) and an external pipe (13) concentric to each other and forming between them spaces for the longitudinal circulation of fluids, the sets of pipes (10) being situated substantially parallel to each other, wherein the intermediate pipes (12) are connected in series by means of curved pipes (20), such that they form a circuit for the circulation of the fluid to be treated, wherein one of the intermediate pipes (12) comprises an open end to the outside of the heat exchanger (1) through which the fluid to be treated can be introduced and another of the intermediate pipes (12) comprises an open end through which the fluid to be treated can be extracted, characterised in that each set of pipes (10) comprises:
- an inner connecting conduit (31) that fluidically connects one end of the internal pipe (11) to an element external to the corresponding set of pipes (10),

- an intermediate connecting conduit (32) that fluidically connects the other end of its internal pipe (11) to the adjacent end of its external pipe (13); and

- an outer connecting conduit (33) that fluidically connects the other end of its external pipe (13) to another element external to the corresponding set of pipes (10).
Heat exchanger (1) according to claim 1, wherein the curved pipes (20) comprise removable connecting means (21) to the intermediate pipes.
Heat exchanger (1) according to any one of the preceding claims, wherein the internal pipes (11) protrude at both ends with respect to the external pipes (13), so that the inner connecting conduits (31) and the intermediate connecting conduits (32) only pass through the intermediate pipes (12).
Heat exchanger (1) according to any one of the preceding claims, wherein the intermediate pipes (12) protrude at both ends with respect to the inner (11) and external pipes (13).
Heat exchanger (1) according to any one of the preceding claims, wherein the inner connecting conduits (31) and the intermediate connecting conduits (32) are longitudinally connected to the internal pipes (11).
Heat exchanger (1) according to any one of the preceding claims, wherein the intermediate connecting conduits (32) are connected to the external pipes (13) from the outside thereof and in a radial direction.
Heat exchanger (1) according to any one of the preceding claims, characterised in that it comprises three sets of pipes (10), where the intermediate pipes (12) and the internal connecting conduits (31) and external connecting conduits (33) of one of the sets of pipes (10) are connected in turn to the corresponding intermediate pipes (12) and internal connecting conduits (31) and external connecting conduits (33) of the other two sets of pipes (10).
Heat exchanger (1) according to claim 7, wherein two of the sets of pipes (10) are at the same height and a third one is above the first two.
Heat exchanger (1) according to any of the preceding claims, characterised in that it comprises a cover (40) in which the sets of pipes (10) are housed, preferably in the form of a cylinder with legs (41) for support on the ground and/or connection means (42) for lifting.
Cooling system characterised in that it comprises a heat exchanger (1) as described in any one of the preceding claims.
Cooling system according to claim 10, characterised in that it comprises a pump for pumping a fluid to be cooled through the intermediate pipes (12) of the heat exchanger (1) and a pump for pumping a coolant through a circuit provided for this purpose in the heat exchanger (1).
Cooling system according to claim 10 or 11, characterised in that it comprises means for regulating the cooling temperature, whereby said temperature can be regulated preferably between -8°C and 8°C.