MONOBLOC ASSEMBLY FOR A DEVICE WHICH CAN CARRY OUT TRANSFER OF HEAT

Abstract

A method for transfer of heat between a first and a second fluid, wherein the first and the second fluid circulate respectively on both sides of a thermally conductive wall of a monobloc assembly formed in a single piece. The monobloc assembly, which is arranged in the interior of a device, includes: a first, three-dimensional, cellular, thermally conductive structure through which the first fluid can pass; at least the thermally conductive wall; and a second, three-dimensional, cellular, thermally conductive structure through which the second fluid can pass. The first and second three-dimensional, cellular structures are situated on both sides of and integral with the wall such that heat transfer is carried out from the first to the second fluid through the wall, and both first and second fluids are under liquid phases and under gaseous phases, with the liquid phases circulating in a direction opposite that of the gaseous phases.

Claims

1-18. (canceled)

19. A method for transfer of heat between a first and a second fluid, wherein the first and the second fluid circulate respectively on both sides of a thermally conductive wall of a monobloc assembly formed in a single piece, which assembly is arranged in the interior of a device, the monobloc assembly comprising: a first, three-dimensional, cellular, thermally conductive structure through which the first fluid can pass; at least said wall; and a second, three-dimensional, cellular, thermally conductive structure through which the second fluid can pass; the first, three-dimensional, cellular structure and the second, three-dimensional, cellular structure being situated on both sides of said wall and being integral with said wall; such that the transfer of heat is carried out from the first fluid to the second fluid through said wall, and each of the first and second fluids is both under liquid phase and under gaseous phase, with the liquid phase of the first fluid circulating in a direction opposite that of the gaseous phase of the first fluid, and the liquid phase of the second fluid circulating in a direction opposite that of the gaseous phase of the second fluid.

20. The method for transfer of heat as claimed in claim 19, the speed of the gaseous phase of each of the first and second fluids being between 0.5 m/s and 5 m/s, preferably between 1 m/s and 3 m/s.

21. The method for transfer of heat as claimed in claim 19, wherein material is transferred simultaneously with the transfer of heat.

22. A device which can carry out transfer of heat between a first and a second fluid circulating respectively on both sides of a thermally conductive wall, said device being configured to implement the method as claimed in claim 19, the device comprising a monobloc assembly formed in a single piece comprising: a first, three-dimensional, cellular, thermally conductive structure through which the first fluid can pass; at least said wall; and a second, three-dimensional, cellular, thermally conductive structure through which the second fluid can pass; the first, three-dimensional, cellular structure and the second, three-dimensional, cellular structure being situated on both sides of said wall and being integral with said wall; such that the transfer of heat is carried out from the first fluid to the second fluid through said wall.

23. The device as claimed in claim 22, the device being a distillation column, an absorption column, a stripping column or a heat exchanger.

24. The device as claimed in claim 22, the device being an HIDiC distillation column, in particular a concentric HIDiC distillation column.

25. A monobloc assembly designed for the implementation of a method as claimed in claim 19, said monobloc assembly being designed to be arranged in the interior of a device configured to implement said method, which can carry out transfer of heat between a first and a second fluid circulating respectively on both sides of a thermally conductive wall, said monobloc assembly being formed in a single piece and comprising: a first, three-dimensional, cellular, thermally conductive structure through which the first fluid can pass; at least said wall; and a second, three-dimensional, cellular, thermally conductive structure through which the second fluid can pass; the first, three-dimensional, cellular structure and the second, three-dimensional, cellular structure being situated on both sides of said wall and being integral with said wall; such that the transfer of heat is carried out from the first fluid to the second fluid through said wall.

26. The monobloc assembly as claimed in claim 25, the wall having a cylindrical form.

27. The monobloc assembly as claimed in claim 26, the first three-dimensional, cellular, thermally conductive structure filling the interior of the cylinder formed by the wall, and the second, three-dimensional, cellular, thermally conductive structure matching the contour of the wall and extending radially.

28. The monobloc assembly as claimed in claim 27, the second, three-dimensional, cellular, thermally conductive structure having a surface opposite the wall with a cylindrical form.

29. The monobloc assembly as claimed in claim 25, at least one, and in particular each of the cellular structures comprising a plurality of strands with a thickness of between 1 mm and 3 mm.

30. The monobloc assembly as claimed in claim 25, at least one, and in particular each of the cellular structures having a level of vacuum of between 85% and 99%.

31. The monobloc assembly as claimed in claim 25, at least one, and particular each of the cellular structures having a volume area of between 100 and 1000 m.sup.2/m.sup.3.

32. The monobloc assembly as claimed in claim 25, at least one, and in particular each of the cellular structures being a regular structure.

33. The monobloc assembly as claimed in claim 25, at least one, and in particular each of the cellular structures having Kelvin cells and/or cells which are not Kelvin cells.

34. The monobloc assembly as claimed in claim 25, at least one, and in particular each of the cellular structures being a metal foam or a silicon carbide foam, in particular a foam made of copper, titanium, stainless steel or aluminum.

35. A method for producing a monobloc assembly as claimed in claim 25, comprising: introduction of a liquid into a pre-form; solidification of the liquid in the pre-form; removal from the mold of the solid thus obtained, such as to obtain the monobloc assembly.

36. The method as claimed in claim 35, with the removal from the mold comprising a step of thermal de-coring.

Description

[0096] The invention will be able to be better understood by reading the following detailed description of non-limiting embodiments thereof, and by examining the appended drawing, in which:

[0097] FIG. 1

[0098] FIG. 1 represents a monobloc assembly according to the invention.

[0099] FIG. 2

[0100] FIG. 2 represents the monobloc assembly in FIG. 1 in perspective.

[0101] FIG. 3

[0102] FIG. 3 is a transverse cross-section of the monobloc assembly in FIG. 1.

[0103] FIG. 4

[0104] FIG. 4 represents an enlargement of the first, three-dimensional, cellular structure of the monobloc assembly in FIG. 1.

[0105] FIG. 5

[0106] FIG. 5 represents a device which can carry out transfer of heat according to the invention.

[0107] FIG. 6

[0108] FIG. 6 represents schematically the operation of an HIDiC column according to the invention.

[0109] FIG. 7a

[0110] FIG. 7a is a first graph comparing the thermal performance of a monobloc assembly according to the invention with packing according to the prior art.

[0111] FIG. 7b

[0112] FIG. 7b is a second graph comparing the thermal performance of a monobloc assembly according to the invention with packing according to the prior art.

[0113] FIG. 7c

[0114] FIG. 7c is a third graph comparing the thermal performance of a monobloc assembly according to the invention with packing according to the prior art.

[0115] FIG. 7d

[0116] FIG. 7d is a fourth graph comparing thermal performance of a monobloc assembly according to the invention with packing according to the prior art.

[0117] FIG. 8a

[0118] FIG. 8a represents a first step of a method for production of a three-dimensional, cellular, thermally conductive structure of a monobloc assembly according to the invention.

[0119] FIG. 8b

[0120] FIG. 8b represents a second step of a method for production of a three-dimensional, cellular, thermally conductive structure of a monobloc assembly according to the invention.

[0121] FIG. 8c

[0122] FIG. 8c represents a third step of a method for production of a three-dimensional, cellular, thermally conductive structure of a monobloc assembly according to the invention.

[0123] FIG. 8d

[0124] FIG. 8d represents a fourth step of a method for production of a three-dimensional, cellular, thermally conductive structure of a monobloc assembly according to the invention.

[0125] FIG. 8e

[0126] FIG. 8e represents a fifth step of a method for production of a three-dimensional, cellular, thermally conductive structure of a monobloc assembly according to the invention.

[0127] FIG. 8f

[0128] FIG. 8f represents a sixth step of a method for production of a three-dimensional, cellular, thermally conductive structure of a monobloc assembly according to the invention.

[0129] FIGS. 1, 2 and 3 represent a monobloc assembly 1 for a device 10 which can carry out transfer of heat between a first and a second fluid circulating respectively on both sides of a thermally conductive wall 3.

[0130] The monobloc assembly 1 comprises: [0131] a first three-dimensional, cellular, thermally conductive structure 2 through which the first fluid can pass; [0132] said wall 3; and [0133] a second, three-dimensional, cellular, thermally conductive structure 4 through which the second fluid can pass.

[0134] The first, three-dimensional, cellular structure 2 and the second, three-dimensional, cellular structure 4 are situated on both sides of said wall 3 and are integral with said wall 3.

[0135] The heat is transferred from the first fluid to the second fluid through said wall 3.

[0136] The first, three-dimensional, cellular structure 2 and the second, three-dimensional, cellular structure 4 comprise a plurality of strands 6 with a thickness e.sub.b of between 1 mm and 3 mm.

[0137] The wall 3 has a cylindrical form around an axis Y.

[0138] The wall 3 has a thickness e.sub.p of 5 mm.

[0139] The first, three-dimensional, cellular, thermally conductive structure 2 fills the interior of the cylinder formed by the wall 3.

[0140] The second, three-dimensional, cellular, thermally conductive structure 4 matches the contour of the wall 3 and extends radially.

[0141] The surface of the second, three-dimensional, cellular, thermally conductive structure 4 opposite the wall 3 has a cylindrical form around the axis Y.

[0142] The first, three-dimensional, cellular structure 2 has a diameter I.sub.1 of 80 mm.

[0143] The second, three-dimensional, cellular structure 4 has a radial dimension I.sub.2 of 25 mm.

[0144] As illustrated in FIG. 4, each cell 5 has a characteristic dimension I.sub.a of 10 mm.

[0145] The first and second cellular structures 2, 4 are metal foams with Kelvin cells.

[0146] FIG. 5 represents a device 10 according to the invention. The device 10 is a concentric HIDiC column comprising a monobloc assembly 1 according to the invention.

[0147] The device 10 comprises an enrichment column, known as the inner column, comprising a first, three-dimensional, cellular, thermally conductive structure 2, and an impoverishment column, known as the outer column, comprising a second, three-dimensional, cellular, thermally conductive structure 4, the enrichment column and the impoverishment column being concentric.

[0148] The thermal performance levels of a monobloc assembly 1 according to the invention were tested on a concentric HIDiC column and compared with packing according to the prior art in FIGS. 7a, 7b, 7c and 7d.

[0149] On both sides of the wall, the monobloc assembly 1 tested comprises an aluminum metal foam with a level of vacuum of 85%, and having Kelvin cells.

[0150] The packing according to the prior art is “super ring” packing sold by the company Raschig Gmbh.

[0151] The concentric HIDiC column on which the tests were carried out is a column one meter high comprising an inner column with a diameter of 80 mm and an outer column with a diameter of 150 mm.

[0152] The inner column is supplied with cyclohexane at a flow rate, known as the “spraying flow rate”, of 12 kg/h to 40 kg/h.

[0153] The outer column is supplied with water vapor at a flow rate of 0.8 kg/h to 5 kg/h, at a pressure of between 1.8 atm and 2.2 atm.

[0154] FIGS. 7a, 7b, 7c and 7d represent the heat exchanged according to the spraying flow rate for the monobloc assembly 1 on the other hand and for the packing according to the prior art, known as the “packing” on the other hand, respectively for a temperature difference on both sides of the wall ΔT of 1° K, 1.81° K, 2.61° K, and 5.65° K.

[0155] The results given in FIGS. 7a, 7b, 7c and 7d show that the monobloc assembly 1 according to the invention provides better thermal performance than the packing according to the prior art.

[0156] The mean value of the gain is approximately 100%: the monobloc assembly 1 according to the invention doubles the heat exchange in comparison with the packing according to the prior art.

[0157] In addition, three tests were carried out on a concentric HIDiC column according to the invention, represented highly schematically in FIG. 6, comprising a monobloc assembly 1 according to the invention.

[0158] The monobloc assembly 1 used for these three tests comprises, on both sides of the wall 3, an aluminum foam with a level of vacuum of 85%, and having

[0159] Kelvin cells.

[0160] For each test, the results were analyzed with the n-heptane (C7)/cyclohexane (C6) system. The three tests (tests 1, 2 and 3) were carried out respectively with a pressure in the inner column Pint of 1.3 bar, 1.5 bar and 1.5 bar. All of the results are summarized in tables 1 to 3, corresponding respectively to tests 1 to 3, with the values measured being represented in FIG. 6.

TABLE-US-00001 TABLE 1 F W D F′ V1 V1′ L1 V2 Total flow kg/h 11.80 3.00 8.80 24.30 21.30 21.30 12.51 8.80 rate Mass C6 0.49 0.12 0.62 0.44 0.49 0.49 0.39 0.62 fraction C7 0.51 0.88 0.38 0.56 0.51 0.51 0.61 0.38 Temperature ° C. 29.57 95.66 95.83 84.72 89.21 101.08 97.23 91.08 Pressure bar 1.01 1.01 1.35 1.01 1.01 1.35 1.35 1.35

TABLE-US-00002 TABLE 2 F W D F′ V1 V1′ L1 V2 Total flow kg/h 11.75 10.82 0.92 28.92 18.10 18.10 17.18 0.92 rate Mass C6 0.47 0.43 0.94 0.61 0.71 0.71 0.70 0.94 fraction C7 0.53 0.57 0.06 0.39 0.29 0.29 0.30 0.06 Temperature ° C. 39.88 87.88 95.22 84.71 84.65 98.57 93.78 83.99 Pressure bar 1.01 1.01 1.50 1.01 1.01 1.50 1.50 1.50

TABLE-US-00003 TABLE 3 F W D F′ V1 V1′ L1 V2 Total flow kg/h 11.4 2.8 8.6 18.7 15.9 15.9 7.3 8.6 rate Mass C6 0.5 0.1 0.6 0.4 0.5 0.5 0.4 0.6 fraction C7 0.5 0.9 0.4 0.6 0.5 0.5 0.6 0.4 Temperature ° C. 31.5 95.5 100.1 84.8 89.4 105.4 100.6 89.9 Pressure bar 1.0 1.0 1.5 1.0 1.0 1.5 1.5 1.5

[0161] The results of the tests were compared with the results of a conventional distillation column.

[0162] The power to be supplied to the boiler of the conventional distillation column (conventional Qb) was compared with the power supplied to the boiler of the HIDiC column (HIDiC Qb) added to the power consumed by the compressor of the HIDiC column (Pcomp).

[0163] The pessimistic hypothesis according to which the isentropic performance of the compressor of the HIDiC column is 25% was adopted.

[0164] The results are contained in table 4.

TABLE-US-00004 TABLE 4 Total HIDiC Pcomp (KW) Pcomp (kW) HIDiC Conventional Qb (kW) (isentropic) (25% isentropic) (kW) Qb (kW) Gain Test 1 0.31 0.06 0.24 0.55 0.97 43% Test 2 0.04 0.07 0.28 0.32 0.52 57% Test 3 0.3 0.06 0.24 0.54 0.84 36%

[0165] Energy gains of between 36% and 57% were obtained.

[0166] The use of an HIDiC column according to the invention thus makes possible a clear energy gain in comparison with a conventional distillation column.

[0167] FIGS. 8a, 8b, 8c, 8d, 8e and 8f represent different steps of a method for production of a three-dimensional, cellular, thermally conductive structure of a monobloc assembly according to the invention.

[0168] The three-dimensional cellular structure is produced by boiler making techniques.

[0169] Plate cores 20 are produced (FIG. 8a). The pattern which constitutes the cores 20 is for example a Kelvin cell on which the ridges have been chamfered in order to permit infiltration of the metal. The cores 20 are based on sand.

[0170] The cores 20 are agglomerated in a pre-form 21 (FIG. 8b). The cores 20 are arranged by imbrication of the plates.

[0171] A mold is produced and the pre-form 21 is re-molded (FIG. 8c).

[0172] A bath 22 of metal, for example aluminum, is prepared, then the liquid metal 22 is infiltrated into the pre-form (FIG. 8d). The filling system and the temperature of the metal are adapted to the configuration of the three-dimensional cellular structure to be produced. Software which makes it possible to calculate the distances of infiltration of metal can be used.

[0173] The metal is solidified (FIG. 8e).

[0174] The sand is discharged by means of a thermal de-coring process which makes it possible to discharge the sand without damaging the strands (FIG. 8f).

[0175] The metal is finished, and the three-dimensional cellular structure is produced.

[0176] The method for production of the three-dimensional cellular structure comprises checking of the form of the cores, checking of the porosity of the metal before casting, measurement of the temperature of the metal before casting, verification of the metallurgy of the metal before casting, in particular by means of a spectrometer, and visual checking after removal of the sand.