EP1402221B1 - Device and method for storing and regenerating a two-phase coolant fluid - Google Patents

Abstract

The invention concerns a device for storing a two-phase coolant fluid (4) designed to circulate in a heat transfer circuit (10), comprising: a compartment (2) for storing and regenerating the two-phase coolant fluid; at least an indirect heat exchange means (6) between a refrigerant and the coolant fluid (4); a circulating means (8) to circulate the coolant fluid (4) in the heat transfer circuit (10); a two-phase recycling and cooling circuit for the coolant fluid (4). Said device comprises: another compartment for ice slurry conditioning (20), connected to the heat transfer circuit (10); means for introducing part of the coolant fluid (4), enriched in solid phase, into said other compartment; a drawpoint (24) on the storage and regeneration compartment (2), and means for injecting (26, 28) the coolant fluid in liquid phase, into said other compartment; and a mixing member, co-operating with said other compartment.

Description

The present invention relates to the storage and regeneration of a coolant fluid.

By "ice slurry" is meant a coolant fluid comprising two phases of the same body in melting or crystallization equilibrium, for example water added with an antifreeze agent, such as salt, water or alcohol, monoethylene glycol or monopropylene glycol. This body in fusion equilibrium can also be a eutectic. The solid phase in divided form, for example ice microcrystals, is distributed homogeneously in the liquid phase, to the point of obtaining a consistency of the cooling fluid, pasty or viscous, for example sufficiently fluid to be able to pump said fluid. The coolant fluids considered according to the invention are therefore obtained, stored, transported, and used in mixed and homogeneous two-phase form, in particular in a consistency close to a sherbet or ice cream.

The coolant fluids comprise a liquid phase and a solid phase in a homogeneous mixture. These are usually mixtures of water-alcohol, water-ethylene glycol, water-propylene glycol, water-glycerol, water-ammonia, water-potassium carbonate, water-calcium chloride, water-magnesium chloride water-potassium acetate, etc .; other types of mixtures, not containing water, may also be suitable.

Such coolant fluids are very efficient, they absorb heat by melting their solid phase, compared to conventional liquid coolant fluids, which absorb heat, only by heating (sensible heat).

To simplify the presentation of the invention, it will be discussed hereinafter refrigerant fluid ice slurry type, which should be understood as a fluid as previously defined.

By liquid carrier refrigerant fluid, it will be understood, by difference, a fluid essentially in the liquid phase, that is to say with a low concentration, or zero, micro-crystals.

By the document US-A-2,902,839 a storage and regeneration device for a coolant fluid, in diphasic form, is known, but not in the form of ice slurry, intended to circulate only in liquid form in a heat transfer circuit. The latter comprises one or more heat exchangers between the cold refrigerant fluid and in liquid form and the outside.

• un compartiment de stockage du fluide frigo-porteur à l'état diphasique, en équilibre de fusion ;
• au moins un moyen d'échange indirect de chaleur entre un fluide frigorigène et le fluide frigo-porteur, en phase liquide, associé audit compartiment, et plus précisément disposé au sein dudit compartiment ;
• un moyen de circulation, du type pompe, pour faire circuler le fluide frigo-porteur, prélevé à l'état liquide à l'état froid dans ledit compartiment, dans le circuit de transfert de chaleur, et le réinjecter dans ledit compartiment ;
• un circuit de recyclage diphasique et de refroidissement du fluide frigo-porteur au sein dudit compartiment, comportant un point de soutirage en partie inférieure dudit compartiment, ledit circuit de recyclage intégrant le moyen d'échange indirect de chaleur, et comportant un moyen d'aspiration/refoulement de fluide frigo-porteur.

Said device comprises:

• a compartment for storing the coolant fluid in the two-phase state, in melting equilibrium;
• at least one indirect heat exchange means between a refrigerant and the coolant fluid, in liquid phase, associated with said compartment, and more precisely disposed within said compartment;
• circulating means, of the pump type, for circulating the coolant fluid, taken in the cold state in said cold state, into said heat transfer circuit, and reinjecting it into said compartment;
• a two-phase recycling circuit and cooling the cooling fluid within said compartment, comprising a draw-off point in the lower part of said compartment, said recycling circuit incorporating the indirect heat exchange means, and comprising a suction means; / delivery of refrigerant fluid.

The indirect heat exchange means is a scraped surface exchanger, generating a setting of the coolant fluid mass on a scraping surface. The separation of the refrigerant fluid in solid form from the scraping surface requires considerable effort, thus going against a decrease in operating energy consumption for the device.

In accordance with the document EP-0 629 826 there is known a cold transfer device comprising a vertical compartment for storing and feeding a heat transfer circuit with a cooling fluid of the ice slurry type. The device comprises a means for indirect heat exchange between a refrigerant and the coolant fluid, placed outside the storage enclosure. The latter is drawn into the liquid phase at a lower level of the storage compartment, to be reinjected to a higher level, once enriched in solid phase microcrystals.

An extraction means is also provided for supplying the heat transfer circuit with a cooling fluid of the ice slurry type. This extraction means comprises a cone opening on a conduit in the storage compartment. The opening of the cone is at a higher level and the coolant fluid is rich in solid phase (ice micro-crystals). A stirring means is arranged in the cone, so as to create turbulence in the extracted coolant fluid, regenerating the ice slurry.

Such a device does not make it possible to precisely control the concentration of micro-crystals in the cooling fluid of the ice slurry type extracted to feed the heat transfer circuit. In addition, the supply of indirect heat exchange means is under the hydraulic pressure of the coolant fluid contained in the storage compartment. This can be inconvenient during maintenance operations, especially when the storage compartment is very large. A large ice slurry storage height may, with certain mixtures, lead to stratification that may noticeably deteriorate the quality of the ice slurry that will be injected into the installation. Drying of the upper layer may occur, resulting in a suboptimal temperature. This disadvantage is all the more striking when the ice cream is not used continuously.

1. (a) disposer d'un fluide frigo-porteur comprenant une phase solide en équilibre de fusion avec une phase liquide ;
2. (b) faire circuler le fluide frigo-porteur, sous forme liquide, dans un circuit comprenant le ou les échangeurs de chaleur, ainsi que dans un compartiment de stockage et régénération associé à un moyen d'échange indirect de chaleur ;
3. (c) stocker le fluide frigo-porteur dans le compartiment, permettant une décantation entre la phase liquide et la phase solide dudit fluide ;
4. (d) prélever dans le compartiment le fluide frigo-porteur, essentiellement en phase liquide, et le faire circuler dans le moyen d'échange indirect de chaleur, de manière à le transformer en phase solide, laquelle est dissociée aux micro-cristaux ;
5. (e) réinjecter le fluide frigo-porteur riche en micro-cristaux sortant du moyen d'échange indirect de chaleur, dans le compartiment.
   Le but de la présente invention est de stocker et de régénérer, de façon permanente, un fluide frigo-porteur, type coulis de glace, pour qu'il soit opérationnel de façon permanente, même après de longs arrêts d'utilisation.
   Un autre but de la présente invention vise à optimiser la consistance d'un fluide frigo-porteur du type coulis de glace, c'est-à-dire optimiser la concentration de micro-cristaux dans le fluide frigo-porteur et en particulier à contrôler cette concentration, pour obtenir un stockage maximum.
   Un autre but de la présente invention vise à contrôler et à modifier, le cas échéant, cette concentration en micro-cristaux, en vue d'améliorer ou d'adapter les propriétés frigorifiques du fluide frigo-porteur du type coulis de glace, à l'utilisation.
   Un but additionnel de la présente invention vise à simplifier les installations mettant en oeuvre un tel fluide frigo-porteur d'une part, et à faciliter les opérations de maintenance d'autre part.
   Selon l'invention, le dispositif comporte :
   • un autre compartiment de conditionnement sous forme de coulis de glace, connecté au circuit de transfert de chaleur, lui-même alimenté en fluide frigo-porteur du type coulis de glace ;
   • des moyens d'introduction d'une partie du fluide frigo-porteur, enrichie en phase solide, en dehors du moyen d'échange indirect de chaleur dans ledit autre compartiment, à un niveau supérieur ;
   • un point de soutirage complémentaire sur le compartiment de stockage et régénération, en partie inférieure, et des moyens d'injection de fluide frigo-porteur en phase liquide, dans ledit autre compartiment ;
   • et un organe mélangeur coopérant avec ledit autre compartiment, pour mélanger les phases liquide et solide du fluide frigo-porteur.
     En outre, le procédé conforme à l'invention se différencie du procédé identifié précédemment par référence aux étapes dites (a) à (e), par le fait que :
6. (f) on sépare et stocke une partie du fluide frigo-porteur riche en phase solide dans un autre compartiment de conditionnement sous forme de coulis de glace ;
7. (g) on injecte dans ledit autre compartiment une partie de fluide frigo-porteur pauvre en phase solide, prélevée dans le compartiment de stockage et régénération ;
8. (h) on mélange les phases solide et liquide du fluide frigo-porteur dans ledit autre compartiment ;
9. (i) on utilise le fluide frigo-porteur obtenu sous (h) pour mettre en oeuvre l'étape (a), par prélèvement du fluide frigo-porteur conditionné sous forme de coulis de glace dans ledit autre compartiment, et en le réinjectant, en aval du ou des échangeurs de chaleur du circuit de transfert de chaleur dans le compartiment de stockage et régénération, et/ou à l'entrée du moyen d'échange indirect de chaleur.

There is thus also known a method for storing and regenerating a refrigerant fluid, in diphasic form, for supplying in liquid form, one or more heat exchangers belonging to a heat transfer circuit, consisting of:

1. (a) having a cooling fluid comprising a solid phase in equilibrium with a liquid phase;
2. (b) circulating the cooling fluid, in liquid form, in a circuit comprising the heat exchanger or exchangers, as well as in a storage and regeneration compartment associated with an indirect heat exchange means;
3. (c) storing the coolant fluid in the compartment, allowing decantation between the liquid phase and the solid phase of said fluid;
4. (d) withdrawing the cooling fluid from the compartment, essentially in the liquid phase, and circulating it in the indirect heat exchange means, so as to transform it into a solid phase, which is dissociated with the microcrystals;
5. (e) reinjecting the microcarbon-rich cooling fluid leaving the indirect heat exchange means into the compartment.
   The object of the present invention is to store and regenerate, permanently, a cooling fluid, ice slurry type, so that it is permanently operational even after long periods of use.
   Another aim of the present invention is to optimize the consistency of a cooling fluid of the ice slurry type, that is to say to optimize the concentration of microcrystals in the cooling fluid and in particular to control this concentration, to obtain maximum storage.
   Another object of the present invention is to control and modify, if necessary, this concentration of micro-crystals, with a view to improving or adapting the refrigerating properties of the ice-cooling fluid, 'use.
   An additional object of the present invention is to simplify the installations using such a coolant fluid on the one hand, and to facilitate maintenance operations on the other hand.
   According to the invention, the device comprises:
   • another conditioning compartment in the form of an ice slurry, connected to the heat transfer circuit, itself supplied with a cooling fluid of the ice slurry type;
   • means for introducing a portion of the cooling fluid, enriched in solid phase, outside the indirect heat exchange means in said other compartment, to a higher level;
   • a complementary withdrawal point on the storage and regeneration compartment, in the lower part, and liquid phase coolant injection means, in said other compartment;
   • and a mixing member cooperating with said other compartment, for mixing the liquid and solid phases of the cooling fluid.
     In addition, the process according to the invention differs from the previously identified process by reference to the steps of (a) to (e), in that:
6. (f) separating and storing a portion of the solid phase rich refrigerant fluid in another ice slurry conditioning compartment;
7. (g) injecting into said other compartment a portion of a solid phase poor refrigerant fluid taken from the storage and regeneration compartment;
8. (h) mixing the solid and liquid phases of the coolant fluid in said other compartment;
9. (i) using the cooling fluid obtained under (h) to carry out step (a), by taking the cooling fluid conditioned in the form of ice slurry in said other compartment, and re-injecting it, downstream of the heat exchanger (s) of the heat transfer circuit in the storage and regeneration compartment, and / or at the inlet of the indirect heat exchange means.

• au moins un disque creux monté fixe dans l'enceinte de cristallisation au contact du flux de circulation du fluide frigo-porteur de l'orifice de prélèvement à l'ouverture d'expulsion, ledit disque étant traversé intérieurement par un fluide frigorigène en cours d'évaporation ou un frigo-porteur à plus basse température ;
• un ensemble de bras de balayage montés sur un axe, lequel est entraîné en rotation par un moto-réducteur, et disposés par rapport au(aux) disque(s) de manière à balayer sa surface au contact du fluide frigo-porteur, et expulser le fluide frigo-porteur enrichi en phase solide vers l'ouverture expulsion.

According to one embodiment of the device according to the invention, the indirect heat exchange means comprises:
a crystallization chamber provided, on the one hand, with at least one solid-phase depleted refrigerant-carrying fluid port communicating with the storage and regeneration compartment in the lower part, and
on the other hand, an expulsion opening of the cooling fluid (4) enriched in solid phase;

• at least one hollow disk fixedly mounted in the crystallization chamber in contact with the circulation flow of the coolant fluid from the sampling orifice to the expulsion opening, said disc being traversed internally by a refrigerant in the course of evaporation or a cooler at a lower temperature;
• a set of sweeping arms mounted on an axis, which is rotated by a geared motor, and arranged relative to the disk (s) so as to sweep its surface in contact with the cooling fluid, and expel the coolant fluid enriched in solid phase towards the expulsion opening.

According to one embodiment of the device according to the invention, the indirect heat exchange means comprises a set of hollow disks, arranged parallel to each other and spaced apart, and in that at least a portion of the arms mounted on the axis of the geared motor, are angularly offset relative to each other, and passing from one disk to the adjacent disk, or from one face of a disk to its adjacent face, to force the circulation of the coolant fluid inside the crystallization chamber, the set of scanning arms thus constituting the suction / discharge means for recycling the coolant fluid within storage compartment and regeneration.

According to one embodiment, the device according to the invention comprises a plurality of indirect heat exchange means, associated with a single storage and regeneration compartment, and distributed around said compartment, which concentrically extends around the only other packaging compartment.

The device according to the invention has the advantage of keeping the coolant fluid in motion, throughout its circulation in the two compartments, respectively of storage and regeneration, and of conditioning, in particular in the exchange medium. indirect heat, thus avoiding a build-up that may block the flow of frozen fluid.

Another advantage is related to the large amount of coolant fluid, which can be stored in two-phase fusion equilibrium, in anticipation of a supply of any cold transfer circuit.

• la figure 1 représente une vue en coupe d'un dispositif de stockage, régénération et conditionnement, conforme à l'invention ;
• la figure 2 est une vue schématique et partielle du dispositif de dessus de la figure 1 :

• les figures 3 et 4 sont des vues en coupe du moyen d'échange indirect de chaleur, incorporé dans le dispositif conforme à l'invention, respectivement en coupe perpendiculaire à l'axe, et selon l'axe dudit moyen ;
• les figures 5 à 9 sont des détails des figures 3 et 4 ;
• la figure 10 est une vue en coupe d'un autre exemple de réalisation d'un dispositif conforme à l'invention ;
• la figure 11 est une vue selon la ligne A-A de la figure 10 ;
• la figure 12 représente un détail du moyen d'échange indirect de chaleur du dispositif conforme à l'invention ;
• la figure 13 représente une coupe éclatée selon la ligne XIII-XIII de la figure 12.

Other characteristics and advantages of the invention also of the detailed description hereafter, with reference to the drawings, are given by way of non-limiting examples, in which:

• the figure 1 represents a sectional view of a storage, regeneration and packaging device according to the invention;
• the figure 2 is a schematic and partial view of the top device of the figure 1 :

• the Figures 3 and 4 are sectional views of the indirect heat exchange means, incorporated in the device according to the invention, respectively in section perpendicular to the axis, and along the axis of said means;
• the Figures 5 to 9 are details of Figures 3 and 4 ;
• the figure 10 is a sectional view of another embodiment of a device according to the invention;
• the figure 11 is a view along line AA of the figure 10 ;
• the figure 12 represents a detail of the indirect heat exchange means of the device according to the invention;
• the figure 13 represents an exploded section along line XIII-XIII of the figure 12 .

The figure 1 is a sectional view of a storage device, regeneration and packaging according to the invention. The latter comprises a storage and regeneration compartment 2 containing a coolant fluid 4 in the diphasic state in melting or crystallization equilibrium. The device according to the invention also comprises means for indirect heat exchange 6 between a refrigerant and the coolant fluid 4 essentially in the liquid phase. The indirect heat exchange means 6 is associated with the storage and regeneration compartment 2.

A circulation means 8 of the pump type represented for example at the figure 2 is provided for circulating the coolant fluid 4 taken from the storage and regeneration compartment 2, in a heat transfer circuit 10 comprising one or more heat exchangers 12. The heat transfer circuit 10 opens downstream of the means heat exchanger 12 in the storage and regeneration compartment 2.

As a variant not shown in the figures, it is also possible to reinject the coolant fluid 4, downstream of the heat exchange means or means 12, directly into the indirect heat exchange means 6 if the return of the The coolant fluid 4 is at a temperature higher than the crystallization temperature.

The heat transfer circuit 10 thus opens for example into the storage and regeneration compartment 2, through an opening 2a.

The volume into which the heat transfer circuit 10 opens is preferably partially separated or delimited with respect to the remainder of the storage and regeneration compartment 2, and may comprise in its lower part grids 14 capable of confining the fluid of a solid-state cooler 4 in said storage and regeneration compartment 2. The grids 14, thus constituting a filter, can be eliminated when the storage and regeneration compartment 2 is sufficiently large to obtain good decantation of the cooling fluid 4 in liquid phase, down.

The storage and regeneration compartment 2 delimits a central decantation zone 2b, the lower part of which is arranged on the one hand between the grids 14 and on the other hand between two partition walls 16 and 18. The first separation wall 16 makes it possible to obtaining a partial separation between the storage and regeneration zone 2b and the zone comprising the indirect heat exchange means 6. The second separation wall 18 makes it possible to obtain a partial separation between the storage and regeneration zone 2b and another packaging compartment 20 in the form of an ice slurry, said coolant fluid 4. This second compartment 20 is connected to the heat transfer circuit 10 through an opening 22 associated with the circulation means 8. The other packaging compartment 20 is also supplied with cooling fluid 4 ice-cold type.

The device according to the invention also comprises a two-phase recycling circuit and cooling of the coolant fluid 4 within the storage and regeneration compartment 2. This two-phase recycling and cooling circuit comprises at least one draw-off point 24. lower portion of said storage compartment and regeneration 2. The grids 14 are spaced from the corresponding side walls 2e to constitute flow corridors opening on the draw point (s) 24, supplying the indirect heat exchange means 6. The circuit recycling and cooling also incorporates indirect heat exchange means 6 and further comprises means for suction and discharge of the coolant fluid 4. The coolant fluid 4 is thus sucked into the indirect exchange means 6, as shown for example in FIG. figure 4 by the arrows "A".

The other conditioning compartment 20 and the indirect exchange means 6 are for example arranged on either side of the central storage and regeneration zone 2b, mainly constituting the storage and regeneration compartment 2 for the cooling fluid. 4.

The other conditioning compartment 20 is supplied at a higher level by at least a portion of the solid-phase enriched refrigerant fluid 4 outside the indirect heat exchange means itself, and using means 72.

A complementary draw-off point on the storage and regeneration compartment 2, and this in the lower part, associated with injection means 26 of coolant fluid 4 in the liquid phase in said other conditioning compartment 20, is also provided.

The coolant fluid 4 in the liquid phase is thus provided in the other packaging compartment 20 for example by means of a distribution tube 28 disposed substantially in its central portion.

A mixing member 30 is also provided to cooperate with the other conditioning compartment 20, so as to mix the liquid and solid phases of the coolant fluid 4 contained in said other compartment 20. The device according to the invention also comprises a level detector 32 for determining the filling level of the other conditioning compartment 20 by the coolant fluid 4 in the form of ice slurry.

According to an exemplary embodiment, the device also comprises a measuring member 34 for determining the solid phase concentration of the cooling fluid 4 in the form of an ice slurry in the other conditioning compartment 20. The measuring member 34 is for example realized with a temperature sensor, or electrical or capacitive conductivity, or opacity measurement means, associated with suitable analysis means, the electronic or microprocessor type.

The circulation means 8 makes it possible to reinject downstream of the heat exchanger or heat exchangers 12 of the heat transfer circuit 10, the cooling fluid 4, for example in the storage and regeneration compartment 2, with the aid of a orifice 2a formed in the latter at a lower level.

According to an alternative embodiment of the device according to the invention, the circulation means 8 and the heat transfer circuit 10 are also connected or only to the indirect heat exchange means 6, in order to directly reinject the fluid therein. cooler 4 downstream of the heat exchanger (s) 12.

The indirect heat exchange means 6 is schematized more precisely to the figures 2 , 3 and 4 .

The indirect heat exchange means 6 comprises a crystallization chamber 6a provided, on the one hand, with at least one sampling orifice 6b of the solid phase depleted refrigerant fluid 4, communicating via the sampling orifices 24 with the storage compartment and regeneration 2 in the lower part, and secondly an expulsion opening 6c of the cooling fluid 4 enriched in solid phase.

The indirect heat exchange means 6 also comprises at least one hollow disk 40 fixedly mounted in the chamber 6a, in contact with the flow of the coolant fluid 4 from the sampling orifice 6b to the opening of the expulsion 6c. The hollow disc 40 is traversed internally by a refrigerant during evaporation, for example NH3. The hollow disc or discs 40 are fed by this refrigerant via a refrigeration unit 50 arranged for example beside the heat exchange means 6. As a variant according to the invention, the refrigerant can be replaced by another refrigerant fluid, distinct from that flowing in the heat transfer circuit 10, but colder.

The indirect heat exchange means 6 also comprises a set of scanning arms 60 mounted on an axis 62, which is rotated by a geared motor 64. The scanning arms 60 are arranged relative to the disk (s). (s) hollow 40, so as to sweep their surface in contact with the coolant fluid 4 and expel the enriched refrigerant fluid 4, during supercooling to the expulsion opening 6c of the chamber 6a . The crystallization of the coolant fluid 4 is thus directly in the flow discharged and expelled. The expulsion of the coolant fluid 4 and more precisely the discharge of this coolant fluid 4 is shown schematically by arrows "R" as shown in FIGS. Figures 4 and 3 . The return of the coolant fluid 4 or the ice slurry is downstream of the heat exchangers 12. The or each hollow disk 40 has a central passage 41 through which the axis 62 passes. The coolant fluid 4 is thus sucked through the sampling openings 6b, to then flow from the passage or passages 41 to the periphery of each hollow disk 40, and this by centrifugation.

An embodiment of a hollow disk 40 is shown in FIGS. figures 12 and 13 . The hollow disk 40 comprises for example two side plates 42, and an intermediate plate 43, each provided with a central passage 41.

The intermediate plate 43, cut into coils 43a, is tightly and tightly gripped between the side plates 42. The coils 43a thus provide the circulation path for a refrigerant, the circulation of which is shown schematically for example by the arrows Fe and Fs on figures 3 and 12 . The arrows Fe and Fs respectively correspond to the directions of entry and exit of the refrigerant circulating in the hollow disk 40.

The indirect heat exchange means 6 comprises for example a set of hollow disks 40 arranged parallel to each other and spaced apart from each other. At least a portion of the sweeping arms 60 mounted on the axis 62 of the gear motor 64 are angularly offset relative to each other, passing from one disk to the adjacent disk, or passing from one to the other. face of a disk to its adjacent face, to force the circulation of the coolant fluid 4 inside the crystallization chamber 6a. The set of sweeping arms 60 thus constitutes the suction and discharge means for recycling the coolant fluid 4 within the storage compartment. and regeneration 2. The rotation of the scanning arms 60 is shown schematically by the arrow "V" at Figures 3 and 4 .

Advantageously, the expulsion opening 6c is shaped, positioned and oriented so as to expel the solid phase enriched refrigerant fluid 4 towards the other conditioning compartment 20, thus constituting means for introducing it into the latter. The scanning arms 60 may have different shapes represented by way of example to Figures 5 to 9 . The scanning arms 60 can thus be curved as shown in FIGS. Figures 6 and 8 , or bent as shown in Figures 5 and 7 . The number of scan arms 60 for scanning a surface of a hollow disk may also vary. Indeed, it is possible as shown in Figures 5 and 6 , to scan a surface of a hollow disk 40 with the aid of two scanning arms 60, or for example with the aid of four scanning arms 60, as shown in FIGS. Figures 7 and 8 . This enumeration is by no means limiting. It is also possible to add more scan arms 60, to scan the same surface. The term "sweeping" must be understood in the broad sense, that is to say also encompassing arms 60 favoring a disturbance of the supercooled boundary layer in the vicinity of the hollow disk 40. By supercooled boundary layer is meant the film which cools in contact with the hollow disc 40. The term "sweeping" does not necessarily mean that there is mechanical contact between the arms and the surface of the hollow disc 40, for example by means of brushes 41 The term "over-cooling" should be understood as cooling at a lower temperature than the usual freezing temperature.

The figure 9 shows an embodiment where the adjacent scanning arms 60 are angularly offset relative to each other.

According to the exemplary embodiment (cf. figure 1 ), the expulsion opening 6c is positioned and oriented so as to expel the solid phase enriched refrigerant fluid 4 in the storage and regeneration compartment 2, and more precisely in the central zone 2b at a higher level. The introduction means 72 then extend to a higher level in said storage and regeneration compartment 2. They comprise movable blades 70 arranged to push the coolant fluid 4 to and into the conditioning compartment 20. The blades movable 70 are advantageously mounted on a chain or a strip driven by a gear motor 74.

According to another exemplary embodiment of the device according to the invention, represented in Figures 10 and 11 , the movable blades 170 are mounted on the horizontal arms 172, themselves fixed on a vertical axis 174 driven by a geared motor 176. The movable blades 170 are for example orientable relative to their horizontal mounting arms 172 as is schematized at figure 11 by the arrows "W".

In this embodiment, the device according to the invention comprises a plurality of indirect heat exchange means 6 (only one of which is shown in FIG. figure 11 ), associated with a single storage compartment and regeneration 2. The indirect heat exchange means 6 are distributed around the storage and regeneration compartment, which itself concentrically concentrates around the only other compartment conditioning 20.

The wall 20a delimiting the other conditioning compartment 20 has a preferential height that does not substantially alter the supply of solid-phase refrigerant fluid 4 from the blades 170. A mixing member 30 immersing in the other compartment of the packaging 20 is for example mounted on the axis 174 and rotates with the latter. For installations of large cooling capacity, that is to say devices having large dimensions, it is possible to provide at the end of each horizontal arm 172, a support wheel 200 rolling on a rim 201 formed in upper part on the wall 2c delimiting the storage and regeneration compartment 2.

The operation of the device shown in Figures 10 and 11 is for the remainder identical to that of the device shown in figure 1 . The cooling source 50 can be placed next to, below, or completely independent of the indirect exchange means 6. The admission of the coolant fluid 4 in the liquid phase in the indirect heat exchange means 6 or more precisely in the enclosure 6a is via ducts 6d opening into the storage and regeneration compartment 2.

The device according to the invention makes it possible to implement a method for storing and regenerating a refrigerant fluid in diphasic form and for supplying one or more heat exchangers 12. This method makes it possible to illustrate the operation of such a device according to the invention. There is thus a cooling fluid 4 comprising a solid phase in equilibrium of melting or crystallization with a liquid phase, and circulating said coolant fluid 4 in the circuit comprising the heat exchangers 12 as well as in a storage and regeneration compartment 2 associated with an indirect heat exchange means 6. The refrigerant fluid 4 is continuously stored in the storage compartment and regeneration, thus allowing a decantation between the liquid phase and the solid phase of said fluid. The removal in said storage and regeneration compartment 2 of the coolant fluid 4, essentially in the liquid phase and the circulation in the indirect heat exchange means 6, make it possible to convert the said fluid into a solid phase, which is dissociated into a microorganism. crystals. The latter rich in micro-crystals is then reinjected into the storage and regeneration compartment 2.

According to the invention, part of the microcrystalline or solid phase-rich refrigerant fluid 4 is separated and stored in the other packaging compartment 20 in the form of an ice slurry. Subsequently, a part of coolant fluid 4, in the liquid phase, or poor in the solid phase, taken from the storage and regeneration compartment 2 is injected into said other conditioning compartment 20 in order to mix the solid and liquid phases of the coolant fluid 4 in said other conditioning compartment 20. The mixed ice slurry in the other conditioning compartment 20 is thus ready to be sucked or pumped into the heat transfer circuit 10. The return of the cooling fluid 4 or ice slurry downstream of the heat exchangers 12 is either directly in the crystallization chamber 6a, or in the storage and regeneration compartment 2 at a lower level.

According to the invention, the method also consists in modulating the amount of solid phase depleted refrigerant fluid 4 which is injected into the other conditioning compartment 20. The method according to the invention also consists in determining in the compartment 20, the solid phase concentration and modify, if necessary, this concentration by acting on the amount of solid phase depleted refrigerant fluid 4 injected into the other conditioning compartment 20.

According to the process according to the invention, it is also possible to determine the level of filling of the other conditioning compartment 20 by the cooling fluid of the ice slurry type, and to use the result of this determination to act on the angular incidence of 170 or the speed of movement of the blades, 70, 170. It is also possible to accelerate, slow down or interrupt if necessary, the various operations of said method and in particular the operations under (f), (g ) and (h). It is thus possible to act on the orientation of the blades 170 to modulate the amount of coolant fluid 4 in the solid phase reinjected into the other conditioning compartment 20.

The amount of coolant fluid 4 in the liquid phase reinjected into the other conditioning compartment 20 is managed by the measuring member 34 determining the concentration of microcrystals.

According to this method, and thanks to the device implementing this method, it is thus possible to produce refrigerating sources for feeding large units or large units, or even urban areas, for air conditioning purposes.

The movement of the cooling fluid 4 enriched in micro-crystals, and optionally promoted by the introduction means, of the blade type 70, 170, generates a movement in the opposite direction of the coolant fluid 4 in the liquid phase in the bottom of the storage compartment and regeneration 2. This movement is advantageously to the crystallization chamber 6a. This promotes the movement of the coolant fluid 4 in the liquid phase towards the crystallization chamber 6a, simultaneously with the displacement of the microcrystalline rich refrigerant fluid towards the other packaging compartment 20. The blades 70 and 170 maintain permanently the upper part rich in crystals or solid phase, in the pasty state, and prevent caking of the crystals. This device is necessary in high capacity assemblies, for example used discontinuously.

Claims (17)

1. Device for storing and regenerating a cooling fluid (4) in two-phase form, intended to circulate through a heat-transfer circuit (10) comprising one or several heat exchangers (12), said device comprising:

   - a storage and regeneration compartment (2) for storing and regenerating the cooling fluid (4) in the two-phase state, in melting equilibrium;

   - at least one indirect heat-exchange means (6) for the exchange of heat between a refrigerant fluid or another cooling fluid and the cooling fluid (4), in liquid phase, associated with said compartment (2);

   - a circulation means (8) of the pump type, for circulating the cooling fluid (4), drawn from said compartment (2), in the heat-exchange circuit (10) and for reinjecting it into said compartment;

   - a two-phase recycling and cooling circuit for recycling and cooling the cooling fluid (4), within said compartment, comprising a tapping point (24) at the lower part of said compartment, said recycling circuit incorporating the indirect heat-exchange means and comprising a means for withdrawing/discharging the cooling fluid (4);

   characterized in that it comprises:

   - another compartment for conditioning in the form of ice slurry, connected to the heat-transfer circuit (10), itself supplied with cooling fluid (4) of the ice slurry type;

   - means for introducing some of the cooling fluid (4) enriched in solid phase, outside of the indirect heat-exchange means, itself into said other compartment, at a higher level;

   - a complementary tapping point (24) on the storage and regeneration compartment (2), in the lower part, and injection means (26, 28) for injecting cooling fluid (4), in liquid phase, into said other compartment;

   - and a mixing member (30), collaborating with said other compartment, for mixing the liquid and solid phases of the cooling fluid (4).
2. Device according to Claim 1, characterized in that it comprises a level detector (32) making it possible to determine the fill level of the conditioning compartment (20) by the cooling fluid (4) in the form of ice slurry.
3. Device according to Claim 1 or 2, characterized in that it comprises a measuring member (34) for determining the solid-phase concentration of the cooling fluid (4), in the form of ice slurry, in the conditioning compartment (20).
4. Device according to any one of Claims 1 to 3, characterized in that the circulation means (8) is designed to reinject, downstream of the heat exchanger or exchangers (12) of the heat-transfer circuit (10), the cooling fluid (4) into the storage and regeneration compartment (2), using an orifice (2a) formed in the latter at a lower level.
5. Device according to any one of Claims 1 to 3, characterized in that the circulation means (8) is connected to the indirect heat-exchange means (6) so that the cooling fluid (4) can be reinjected directly thereinto downstream of the heat exchanger or exchangers (12) of the heat transfer circuit (10).
6. Device according to any one of Claims 1 to 5, characterized in that the indirect heat-exchange means (6) comprises:

   - a crystallization chamber (6a) provided, on the one hand, with at least one tapping orifice (6b) for solid-phase-lean cooling fluid (4), communicating with the storage and regeneration compartment (2) in the lower part and, on the other hand, an expulsion opening (6c) for expelling solid-phase-rich cooling fluid (4);

   - at least one hollow disk (40) mounted fixedly in the crystallization chamber (6a) in contact with the circulating stream of cooling fluid (4) from the tapping orifice (6b) to the expulsion opening (6c), said disc having, passing through it internally, a refrigerant fluid in the course of evaporating or some other cooling fluid at a lower temperature;

   - a set of sweeping arms (60) which are mounted on a spindle (62) which is driven in rotation by a geared motor unit (64), and which arms are arranged with respect to the disk(s) (40) in such a way as to sweep its surface in contact with the cooling fluid (4) and to expel the solid-phase-rich cooling fluid (4) toward the expulsion opening (6c).
7. Device according to Claim 6, characterized in that the indirect heat-exchange means (6) comprises a set of hollow disks (40) which are arranged parallel to one another and spaced apart, and in that at least some of the sweeping arms (60), mounted fixedly on the spindle (62) of the geared motor unit (64) are angularly offset from one another and, from one disc (40) to the next or from one side of the disk (40) to its adjacent side, to force the cooling fluid (4) to circulate within the crystallization chamber (6a), the sweeping arms (60) together thus constituting the withdrawing/discharging means for recycling the cooling fluid (4) within the storage and regeneration compartment (2).
8. Device according to Claim 7, characterized in that the expulsion opening (6c) is shaped, positioned and orientated in such a way as to expel the solid-phase-rich cooling fluid (4) toward the other conditioning compartment (20), thus constituting the means of introduction thereinto.
9. Device according to Claim 7, characterized in that the expulsion opening (6c) is positioned and orientated in such a way as to expel the solid-phase-rich cooling fluid (4) into the storage and regeneration compartment (2) at a higher level, and in that the introduction means extend at a higher level into said storage and regeneration compartment (2) and compose moving blades (70, 170) designed to push the cooling fluid (4) toward and into the other conditioning compartment (20).
10. Device according to Claim 9, characterized in that the blades (170) are mounted on a chain or a belt (72) driven by a geared motor unit (74).
11. Device according to Claim 9, characterized in that the blades (170) are mounted on horizontal arms (172) themselves fixed to a vertical spindle (174) driven by a geared motor unit (176).
12. Device according to Claim 11, characterized in that the blades (170) can be orientated with respect to the horizontal arms (172) supporting them.
13. Device according to any one of Claims 1 to 12, characterized in that it comprises a number of indirect heat-exchange means (6) associated with one and the same storage and regeneration compartment (2) and distributed about the said compartment, which runs concentrically around the sole other conditioning compartment (20).
14. Method for storing and regenerating cooling fluid (4) in two-phase form, intended to supply one or more heat exchangers (12), consisting in:

    (a) having a cooling fluid (4) comprising a solid phase in melting equilibrium with a liquid phase;

    (b) circulating the cooling fluid (4) through a circuit comprising the heat exchanger or exchangers (12) and through a storage and regeneration compartment (2) associated with an indirect heat-exchange means (6);

    (c) storing the cooling fluid (4) in the compartment (2) to allow the liquid phase and solid phase of said fluid to separate;

    (d) tapping from said compartment (2) the cooling fluid (4) essentially in the liquid phase and circulating it through the indirect heat-exchange means (6) so as to convert it to a solid phase, which is broken down into microcrystals;

    (e) reinjecting the cooling fluid (4) rich in microcrystals leaving the indirect heat-exchange means (6) into said compartment (2);
    characterized in that it consists in:

    (f) separating and storing some of the solid-phase-rich cooling fluid (4) in another conditioning compartment (20) in the form of ice slurry;

    (g) injecting into said other compartment some of the liquid-phase or solid-phase-lean cooling fluid (4) tapped from the storage and regeneration compartment (2);

    (h) mixing the solid and liquid phases of the cooling fluid (4) in said other compartment (20);

    (i) using the cooling fluid (4) obtained in (h) to carry out step (a) by tapping cooling fluid (4) conditioned in the form of ice slurry from said other compartment (20) and reinjecting it, downstream of the heat exchanger or exchangers (12) of the heat-transfer circuit (10) into the storage and regeneration compartment (2), and/or at the inlet to the indirect heat-exchange means.
15. Method according to Claim 14, characterized in that it consists in altering the amount of solid-phase-lean cooling fluid (4) injected into the other conditioning compartment (20).
16. Method according to Claim 14, characterized in that it consists in determining, in the other conditioning compartment (20), the solid phase concentration and in altering this concentration as appropriate by acting in accordance with Claim 15.
17. Method according to any one of Claims 14 to 16, characterized in that it consists in:

    - determining the fill level of the conditioning compartment (20) with cooling fluid (4) of the ice slurry type;

    - and using the result of this determination to accelerate, direct, slow down or, as appropriate, interrupt the operations in accordance with (f), (g) and (h);

    - or alter the inclination of the blades (70, 170).

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