WIRE FILLING FOR A GAS-LIQUID EXCHANGE DEVICE WITH RADIAL HEAT TRANSFER CAPACITY

Abstract

The invention relates to a basic wire packing unit made of a thermally conductive material, for a gas-liquid exchange apparatus, consisting of three first wires (51, 52, 53) comprising a common upper end (54) located at the apex of an irregular tetrahedron, and each extending vertically to a lower end (57, 55, 56). One of these lower ends (55) is connected to a common upper end (58) of three second vertical wires (59, 510, 511) located at the apex of a regular tetrahedron. A lower portion (515) of the first wire (52) connected to the common upper end (58) of the three second wires has a first curvature, and an upper portion (516) of one of the three second wires (59) connected to the common upper end (58) of the three second wires has a second curvature, the inverse of the first curvature.The unit cell further comprises at least one element of a thermally conductive material oriented horizontally (517). Figure for the abbreviation: Figure 5.

Description

Title of the invention: WIRE FILLING FOR A GAS-LIQUID EXCHANGE DEVICE WITH RADIAL HEAT TRANSFER CAPACITY technical field

[0001] The invention relates to a wire packing, that is to say comprising wires, or even made up of wires, for a gas-liquid exchange apparatus such as a distillation column.

[0002] More specifically, the invention relates first of all to an elementary mesh, or elementary motif, of wire filling.

[0003] The invention then relates to a filling element comprising these elementary meshes or motifs.

[0004] The invention also relates to a lining comprising these lining elements.

[0005] The invention also relates to a method for preparing a filling according to the invention.

[0006] Other objects of the invention are a packing block formed based on a packing according to the invention, an internal for an “HIDiC” column made up of several such packing blocks and a column with an internal thermal coupling comprising such an internal.

[0007] The invention also relates to a gas-liquid exchange apparatus comprising a packing according to the invention.

[0008] The technical field of the invention can, in general, be defined as that of packings for gas / liquid exchange devices such as distillation columns, absorption columns (with or without chemical reaction) and gas scrubbing columns.

[0009] The invention finds its application in particular in columns with internal thermal coupling, or energy-integrated distillation columns, called "Heat Integrated Distillation Column" ("HIDiC") in English. PREVIOUS STATE OF THE ART

[0010] A packed column, whether it is a distillation column or otherwise, is a column which is filled with elements to increase the contact surface between a gaseous phase and a liquid phase.

[0011] The packing creates a series of obstacles in the path of the liquid and gas within the column and allows: - to increase the contact area between the two phases; - to increase the residence time of the two phases in the column and therefore their contact time; - to create a turbulent flow regime in the gas phase and recirculation in the liquid phase.

[0012] The efficiency of a packed column depends on the surface area of ​​the packing, the contact time between the two phases, gas and liquid, and the hydrodynamics within each phase. These phases must be in contact homogeneously along the entire length of the column and across its entire cross-section.

[0013] Distillation columns can be tray columns or packed columns as defined above.

[0014] Currently commercially available fillings are of two types: structured fillings and loose fillings, or simply fillings. Both types of filling are based on the same principle: the flow of a liquid film over a flat surface.

[0015] One of the first structured linings consisted of sheets, corrugated metal sheets.

[0016] The improvements made to these linings, which increase their performance, are: - the modification of the surface condition of corrugated sheets, most often by adding roughness or perforations which will create turbulence and improve wettability; - machining of strips made up of twisted elements equipped with notches; - the addition of flat walls between the corrugated sheets.

[0017] The metal sheets can also be replaced by woven metal fabrics. These woven fabrics develop large contact surfaces and thus significantly increase transfer efficiency. However, it appears that these packings require fluids with low fouling properties and a very homogeneous liquid distribution. Furthermore, these packings are limited to shallow beds because they are unable to maintain good liquid distribution over a great height. Finally, due to their very tight mesh, these packings made of woven metal fabrics have low hydrodynamic capacity. For these reasons, these packings are not used, or are used very little, on an industrial scale, but rather only on a pilot laboratory scale.

[0018] Recently, fillings made of wires, and generally having a lattice structure ("lattice"), have been proposed.

[0019] Indeed, the flow of liquid, in the form of a film, on a wire forming part of a packing, has an interfacial surface greater than the geometric surface of the wire.

[0020] On the other hand, in the case of packings made of plates, the interfacial surface of the liquid flow on a plate is more or less equal to the geometric surface (neglecting waves at the interface and problems of wettability).

[0021] Thus, for the same geometric surface, the interfacial surface is higher for a packing made up of wires than for a packing made up of plates, in the case where the entire surface of the wire is wetted by the liquid.

[0022] These fillings made up of wires, and generally having a lattice structure, also called wire "lattice" fillings, can have different geometries, including a fractal structure geometry created by the assembly of regular tetrahedra or a geometry created by the assembly of structures analogous to DNA (deoxyribonucleic acid).

[0023] These wire packings are more efficient in terms of mass transfer and pressure drop than known structured packings.

[0024] Thus, document FR-A1-3 113 610 describes a wire packing for a mass exchange apparatus, in particular a gas-liquid exchange apparatus, such as a distillation column. The wires of this packing have a cross-section whose general shape is a polygon, at least one side of said polygon being concave and / or convex. These wires form elementary structures, also called basic structures, which are repeated and assembled in space to form the packing.

[0025] The elementary structures can be regular or irregular polyhedra.

[0026] In particular, the filling can be made up of filling motifs formed by the vertical assembly of a lower regular tetrahedron 11 and an upper irregular tetrahedron 12. Figure 5B of document FR-A1-3 113 610, as well as the present [Fig.1], [Fig.2] and [Fig.3] show such an assembly, in which the upper tetrahedron 12 is an irregular tetrahedron and the two tetrahedra 11,12 are connected by two curved, rounded wire portions 13, 14. In other words, the filling motif has two curvatures (“splines”) 13, 14 and the tetrahedra are then called “tetraspline” (TS).

[0027] The packing pattern can be called the TS packing pattern, and the overall packing can be called the TS packing, which can be described as a porous periodic lattice structure composed of the packing patterns described above.

[0028] The TS structure is characterized by the geometric parameters listed below and shown in the present [Fig.1], [Fig.2] and [Fig.3]: - dw: wire diameter (mm), generally the same for all wires, -11: edge length in the lower regular tetrahedron (mm), -12: edge length in the upper irregular tetrahedron (mm), usually equal to 11, - al: angle of the tangent of the curvature (“spline”’) with the vertical in the regular tetrahedron (°), fixed for example at 30°, - a2: angle of the tangent of the curvature (''spline') with the vertical in the irregular tetrahedron (°), fixed for example at 40°.

[0029] The repetition of the elementary motifs along the axes e1, e2, and e3 shown in [Fig. 1] gives a parallelepiped. A cylindrical block of TS filling material, as shown in [Fig. 4], can then be extruded.

[0030] The nomenclature used for TS structures is as follows: TS-X-dw-11, where X is the material constituting the wires (for example PA for polyamide, AI for 316L stainless steel) and where dw and 11 have already been defined above.

[0031] The mass transfer and hydrodynamic capacity of the wire packing described in document FR-A1-3 113 610 are good.

[0032] However, the performance in terms of heat transfer, heat transfer of distillation columns comprising a wire packing, for example a wire packing made of "tetrasplines" like that described in document FR-A1-3 113 610, is very insufficient.

[0033] Furthermore, although wire packings made of "tetrasplines" prevent preferential vertical flows of gas in distillation columns, particularly in "HIDiC" columns, it has been found that wire packings made of "tetrasplines" nevertheless cause a preferential, but this time lateral, flow of gas.

[0034] Moreover, in the material and energy transformation industries, and in particular in the chemical industry, energy costs are mainly due to separation processes which are generally thermal separation processes, and distillation remains one of the most important thermal separation processes in the chemical process industry.

[0035] Nevertheless, despite its numerous advantages and widespread use, the major drawback of distillation lies in its significant energy requirements. Indeed, distillation can generate more than 50% of the operating costs of a plant. It alone accounts for 40% of the total energy consumed by the chemical industry, and approximately 3% of global energy demand.

[0036] Reducing the energy consumption of distillation columns is therefore a major issue in the current energy context.

[0037] The high energy consumption of current distillation columns is coupled with a very low thermodynamic efficiency, between 5 and 15%. Indeed, in a conventional distillation, energy is supplied to the boiler at a high temperature and removed at the condenser at a low temperature, which constitutes a high exergetic degradation.

[0038] In order to increase the energy and / or exergetic efficiency of these columns, several solutions have been proposed, namely: - a column with vapor recompression (VCR), - an adiabatic column, - two columns with external thermal coupling, - a column with internal thermal coupling, or energy-integrated distillation column, called an energy-integrated distillation column (“Heat In-tegrated Distillation Column” in English) (“HIDiC”).

[0039] The HIDiC column combines the advantages of the CRV and adiabatic columns. In an HIDiC column, heat is transferred from the hot enrichment zone to a cooler depletion zone, leading to gradual evaporation throughout the depletion zone, while condensation occurs throughout the enrichment zone. To make this heat exchange possible, the enrichment zone operates at a higher pressure than the depletion zone. The advantage of an HIDiC column over a CRV column lies in the pressure jump required, which is much smaller in an HIDiC column than in a CRV, thus minimizing recompression costs. The principle of HIDiC columns is well documented, and examples are published in the literature demonstrating the expected gains on test mixtures.

[0040] Due to the type of packing they use, "HIDiC" columns can achieve highly efficient heat transfer. However, also due to the type of packing they use, "HIDiC" columns can have a very low separation capacity.

[0041] A "HIDiC" type column is described in document WO-A1-2020 / 169934, which relates to a device capable of carrying out heat transfer between a first and a second fluid flowing respectively on either side of a thermally conductive wall. This device comprises a first three-dimensional, thermally conductive, honeycomb structure capable of being traversed by the first fluid and a second three-dimensional, thermally conductive, honeycomb structure capable of being traversed by the second fluid. The first three-dimensional honeycomb structure and the second three-dimensional honeycomb structure are located on either side of said wall and are integral with said wall, so that the heat transfer is carried out from the first fluid to the second fluid through said wall. This device may be a distillation column, in particular an "HIDiC" column.In the device described in this document, the foam filling provides excellent heat transfer efficiency, but the column's hydrodynamic capacity is very insufficient.

[0042] Therefore, in view of the above, there is a need for a packing for a gas-liquid exchange apparatus, such as a distillation column, which, like the packing described in document FR-A1-3 113 610, possesses excellent properties of mass transfer and high separation capacity, but which also has, unlike this packing, improved performance in terms of thermal transfer, heat transfer, and which in addition does not present preferential flow paths, in particular preferential gas flow paths.

[0043] In view of the above, there is also a need for a packing for a gas-liquid exchange apparatus, such as a distillation column, in particular an "HIDiC" column, which, like the packing described in document WO-A1-2020 / 169934, has excellent heat transfer and mass transfer properties but also, unlike this packing, has a high hydrodynamic capacity.

[0044] There is still a need for a lining which does not have the drawbacks, defects and disadvantages of prior art linings, such as those described above, and which solves the problems posed by prior art linings.

[0045] Finally, there is a need for such a filling which can be manufactured simply, easily, and at a lower cost, even if it has a complex shape.

[0046] The object of the present invention is to meet, among other things, these needs. Description of the invention

[0047] This objective, and others, are achieved, according to the invention, by an elementary mesh (or motif) of wire packing made of a thermally conductive material, for a gas-liquid exchange and / or heat transfer device, for example. This elementary mesh preferably comprises three first wires including a common upper end located at the upper vertex of a first irregular tetrahedron, said three first wires each extending vertically from said first upper end, along three edges of the first tetrahedron, to three lower ends located at the three lower vertices of a base triangle of the first tetrahedron.A lower end of one of the first three wires is connected to a common upper end of three second wires, located at the upper vertex of a second regular tetrahedron. Each of the three second wires extends vertically from the said upper end, along three edges of the second tetrahedron, to three lower ends located at the three lower vertices of a base triangle of the second tetrahedron. A lower portion of the first wire connected to the common upper end of the three second wires has a first curvature, and an upper portion of one of the three second wires connected to the common upper end of the three second wires has a second curvature, the inverse of the first curvature. The unit cell further comprises at least one element of a thermally conductive material oriented horizontally.

[0048] The wires can also be called strands or rods.

[0049] The first curvature and the second curvature can be called "splines".

[0050] Materials defined as thermally conductive materials, also called heat-conducting materials, are known to those skilled in the art.

[0051] By thermally conductive material or heat-conducting material, we generally mean a material whose thermal conductivity X is from 20 to 400 W / mK, preferably from 160 to 400 W / mK

[0052] The elementary filling mesh according to the invention differs from the elementary mesh described in document FR-A1-3 113 610 by the characteristic that it further comprises at least one element made of a thermally conductive material oriented horizontally.

[0053] It has been found that the presence, in the elementary packing mesh according to the invention, of at least one element of a thermally conductive material oriented horizontally greatly improves the heat transfer of a wire packing in which it is integrated, compared to the packing of document FR-A1-3 113 610, and this without degrading the mass transfer and the hydrodynamic capacity of the packing.

[0054] In other words, in a wire packing comprising the elementary packing mesh according to the invention, preferably entirely formed of such elementary meshes, and thanks to said at least one element in a thermally conductive material oriented horizontally, the mass transfer is maintained, the capacity is maintained, or even considerably increased compared to the foam packing of document WO-A1-2020 / 169934, and the heat transfer is improved compared to the packing of document FR-A1-3 113 610, but also, surprisingly, compared to the packing of document WO-A 1-2020 / 169934, even though the foam packings of this document already have excellent heat transfer properties.

[0055] The elementary filling mesh according to the invention can comprise any number of elements made of a thermally conductive material oriented horizontally. For example, it can comprise two, three, four or even five.

[0056] There is no limitation on the form that said elements can take in a thermally conductive material oriented horizontally.

[0057] In the elementary unit cell according to the invention, such an element made of a horizontally oriented thermally conductive material can connect two of said first wires, and / or two of said second wires. At least one such element preferably connects two lower ends of said first wires, and / or two lower ends of said second wires. Said element made of a horizontally oriented thermally conductive material can also, or otherwise, be arranged so that it is capable of connecting one of said tetrahedral vertices of the unit cell. commentary, with a tetrahedral vertex of another elementary unit cell, located at the same height in a wire packing in the constitution of which these elementary units enter.

[0058] Each of the elements in a thermally conductive material oriented horizontally can be chosen from straight horizontal wires, curved or rounded horizontal wires, also called arcs, vertical plates, straight horizontal wires, each supported by vertical half-plates, and straight horizontal wires extending on either side of the vertices of the tetrahedra and supported symmetrically on either side of these vertices by vertical quarter-plates.

[0059] The arcs can be convex or concave in the vertical direction.

[0060] Here too, the wires can also be called strands or rods.

[0061] The invention also relates to a wire filling element comprising, preferably made up of, the assembly of two elementary meshes as described above, superimposed vertically, one of said meshes having undergone a rotation of 180° with respect to a vertical axis, with respect to the other of said meshes.

[0062] The filling element according to the invention possesses all the advantageous properties of the elementary meshes which constitute it and which have already been described above.

[0063] In addition, the rotation of one of the meshes relative to the other by 180° makes it possible to control the flow, in particular the flow of gas, in the wire packing in which this packing element is integrated, and to avoid all preferential flows, in particular lateral gas flows such as those which occur in the packing which is the subject of document FR-A1-3 113 610.

[0064] Thus, the filling element according to the invention comprises, preferably, two elementary meshes each comprising two "Tetraspline" type motifs, i.e. a total of four "Tetraspline" type motifs.

[0065] A first characteristic of the wire packing element according to the invention, namely the presence of elementary meshes with at least one element made of a thermally conductive material oriented horizontally, greatly improves the heat transfer of the wire packing in which it is integrated, while maintaining, or even improving, the mass transfer and hydrodynamic capacity of the packing. A second characteristic, namely the 180° rotation of the two elementary meshes relative to each other, provides a solution to the problem of preferential flows, particularly preferential gas flows.

[0066] The combination of these two characteristics further improves the transfer of matter.

[0067] The assembly of the two elementary meshes can be carried out at any zone of the upper elementary cell and any area of ​​the lower elementary cell, the upper elementary cell being defined as the elementary cell located at the- above the other unit cell along the vertical axis, and the lower unit cell is defined as the unit cell located below the other unit cell along the vertical axis. For example, the lower unit cell can be joined to the upper unit cell by connecting the lower end of a second vertical wire of the second tetrahedron (lower tetrahedron) of the upper unit cell to the upper vertex of the first tetrahedron (upper tetrahedron) of the lower unit cell. Horizontally oriented elements of a thermally conductive material can also, or otherwise, be connected to those of another unit cell.

[0068] The invention also relates to a wire packing comprising, preferably made up of, the assembly of several packing elements as described above.

[0069] The wire packing (global, complete) according to the invention, comprising the assembly of several packing elements, may in particular have a cylindrical shape, which is the most common shape of devices in which the wire packing according to the invention can be used.

[0070] This packing exhibits radial heat transfer capacity. It is particularly optimal for energy integration / heat transfer.

[0071] The invention also relates to a method for preparing a wire packing according to the invention as described above, in which the wire packing is manufactured by an additive manufacturing technique, preferably by a laser melting technique.

[0072] Laser fusion is the preferred manufacturing technique because it allows the required fineness for the desired applications to be obtained.

[0073] The invention also relates to a packing block comprising a body formed of wire packing according to the invention, said packing block preferably being a circular cylindrical packing block for a concentric circular cylindrical "HIDiC" column, typically formed by the vertical assembly of several circular cylindrical packing blocks. The body of said packing block is circular cylindrical in shape and is defined respectively by an upper cross-section and a lower cross-section. It is traversed by an internal circular cylindrical vertical wall extending between this upper cross-section and this lower cross-section and having an upper edge at the level of said upper cross-section.Circular cylindrical vertical orifices pass through said body between said upper straight section and said lower straight section, preferably at the level of the internal circular cylindrical vertical wall. The upper edge of the internal circular cylindrical vertical wall is further provided with a groove for receiving a sealing gasket.

[0074] This packing block can be manufactured by an additive manufacturing technique, for example by a laser melting technique, the packing and the internal circular cylindrical vertical wall preferably being formed simultaneously. In particularly preferred embodiments of the invention, the packing and the internal circular cylindrical vertical wall are further formed as a single piece. Such a feature advantageously makes it possible to obtain particularly good thermal performance, in particular because the packing block obtained is then free of thermal bridges, unlike packing blocks of the prior art in which the packing and the internal circular cylindrical vertical wall consist of two separate parts assembled together.

[0075] Advantageously, a resin can also be placed in the groove of the upper edge of the internal circular cylindrical vertical wall, preferably under the joint, to compensate for roughness, due for example to additive manufacturing and to avoid a complicated machining operation.

[0076] Advantageously, indexes or markers can be provided at the level of the upper cylindrical cross-section of the body formed in wire packing, in particular at the level of the upper edge of the internal cylindrical vertical wall, in order to control the rotation of one block relative to another block, and ensure geometric continuity, when assembling the packing blocks to each other to form the column.

[0077] The invention further relates to an internal for a circular cylindrical concentric “HIDiC” column, consisting of the vertical assembly of several packing blocks according to the invention, as defined above, of circular cylindrical shape, a sealing gasket being placed in the groove of at least one of said packing blocks, preferably of each of said blocks, and the assembly being ensured by: - ​​threaded rods, at least at one of their ends, preferably at least at their two opposite ends, passing through all of said packing blocks and placed in the circular cylindrical vertical orifices of each of said packing blocks, so as to assemble them to each other along the axis of the rods; - and clamping bolts mounted on these threaded rods, engaging with the thread(s) of the latter, so as to lock the assembly of said packing blocks.

[0078] The combined groove with the sealing gasket of a given packing block ensures the sealing of the assembly to the packing block located immediately above, while the threaded rods and associated clamping bolts ensure the pressure resistance of this assembly.

[0079] The invention also relates to a gas-liquid exchange apparatus comprising a wire packing according to the invention, in particular an assembly, notably vertical, of packing blocks according to the invention, and more particularly an internal one according to the invention.

[0080] This gas-liquid exchange apparatus can be chosen from distillation columns, absorption columns, stripping columns and heat exchangers.

[0081] In particular, this gas-liquid exchange apparatus can be a column with an internal thermal coupling, also called an energy-integrated distillation column, known as a "Heat Integrated Distillation Column" ("HIDiC") in English, preferably a concentric "HIDiC" column.

[0082] These gas-liquid exchange devices can be existing devices in which the wire packing according to the invention can replace an old packing with lower performance, or new devices.

[0083] Gas-liquid exchange devices employing wire packing according to the invention can also be called, for simplicity, "packed columns".

[0084] An object of the invention is in particular a column with an internal thermal coupling, also called an energy-integrated distillation column, known as a "Heat Integrated Distillation Column" in English ("HIDiC" - preferably a concentric "HIDiC" column, comprising an internal according to the invention, as defined above, and an external cylindrical vertical wall inside which this internal is disposed.

[0085] The invention will be better understood upon reading the following detailed description of particular embodiments. This description is given by way of illustration and is not limiting and is made in relation to the accompanying drawings. Brief description of the drawings

[0086] [Fig.1] Fig.1 is a 3D perspective view of a "Tetraspline" filling mesh, showing the repetition axes e1, e2, and e3.

[0087] [Fig.2] Fig.2 is a lateral cross-sectional view in the XZ plane of a mesh of "Tetraspline" packing, showing the diameter dw and the axis e3.

[0088] [Fig.3] Fig.3 is a side-section sketch in the XZ plane of a mesh of "Tetraspline" trimming, showing the angles of curvature ("spline") and the lengths 11 and 12 of the threads, strands of the tetrahedra.

[0089] [Fig.4] The [Fig.4] shows a cylindrical block formed of a TS filling.

[0090] [Fig. 5] Fig. 5 is a 3D perspective view that shows an example of a first form of realization of an elementary wire filling mesh according to the invention, in which the horizontally oriented elements are curved horizontal wires or strands.

[0091] [Fig. 6] Fig. 6 is a 3D perspective view that shows an example of a a second embodiment of an elementary wire filling mesh according to the invention, in which the horizontally oriented elements are plates vertical.

[0092] [Fig.7] The [Fig.7] is a 3D perspective view which shows another example of the second embodiment of an elementary wire packing mesh according to the invention.

[0093] [Fig.8] The [Fig.8] is a 3D perspective view which shows yet another example of the second embodiment of an elementary wire packing mesh according to the invention.

[0094] [Fig.9] Fig.9 is a 3D perspective view showing an example of a third embodiment of a wire packing element according to the invention, in which the element includes an additional wire (it is then a “Pentaspline” (PS) element) and this element includes additional horizontal elements.

[0095] [Fig. 10] The [Fig. 10] is a 3D perspective view which shows an example of a fourth embodiment of an elementary wire packing mesh according to the invention, in which the horizontally oriented elements are straight, rectilinear horizontal rods or strands, each supported by vertical half-plates.

[0096] [Fig. 11] The [Fig. 11] is a 3D perspective view which shows an example of a fifth embodiment of an elementary wire packing mesh according to the invention, in which the horizontally oriented elements are made up of straight horizontal rods extending on either side of the vertices of the tetrahedra and supported symmetrically on either side of these vertices by vertical quarter plates.

[0097] [Fig. 12] The [Fig. 12] is a view in the XZ plane of the elementary packing mesh of the [Fig. 11].

[0098] [Fig. 13] The [Fig. 13] is a partial cross-sectional view of yet another example of the fifth embodiment of an elementary wire filling mesh according to the invention, without a net.

[0099] [Fig. 14] The [Fig. 14] shows, in the XZ plane, a geometry of a classic TS filling with a vertical repetition of the elementary TS motifs along an inclined axis e3 and a horizontal repetition along the X axis.

[0100] [Fig. 15] The [Fig. 15] shows, in the XZ plane, a geometry of a wire packing according to the invention comprising the assembly of elementary meshes TS, formed by the periodic repetition, along the X and Z axes, of the assembly of two elementary meshes, one of which has undergone a rotation of 180 degrees with respect to the other along the Z axis.

[0101] [Fig. 16] Fig. 16 is a 3D perspective view showing a wire packing element according to the invention, comprising two elementary meshes according to the fifth embodiment of the invention described below, the lower mesh having underwent a rotation of 180° with respect to the vertical Z axis.

[0102] [Fig. 17] The [Fig. 17] shows a packing block according to the invention for a circular cylindrical concentric “HIDiC” column.

[0103] [Fig. 18] Fig. 18 shows constituents of a packing block according to the invention, for a circular cylindrical concentric “HIDiC” column, more particularly, in a / a perspective view of the circular cylindrical internal vertical wall of this packing block, and in b / a perspective view cut at 1 / 4 of this packing block.

[0104] [Fig. 19] The [Fig. 19] illustrates the assembly, to constitute an internal according to the invention, of the internal circular cylindrical vertical walls of two packing blocks according to the invention, in perspective cut at 1 / 4.

[0105] DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

[0106] With reference to [Fig. 5], the elementary wire packing unit according to the invention, made of a thermally conductive material, for a gas-liquid exchange apparatus, comprises three first wires 51, 52, 53 including a common upper end 54 located at the upper vertex of a first irregular tetrahedron, said three first wires 51, 52, 53 extending each vertically from said first common upper end 54, along three edges of the first tetrahedron, to three lower ends respectively 57, 55, 56 located at the three lower vertices of a base triangle of the first tetrahedron, a lower end 55 of one of said three first wires (referenced 52 on [Fig. 5]5]) being connected to a common upper end 58 of three second wires 59, 510, 511 located at the upper vertex of a second regular tetrahedron, said three second wires 59, 510, 511 extending each vertically from said common upper end 58, along three edges of the second tetrahedron, to three lower ends respectively 514, 512, 513 located at the three lower vertices of a base triangle of the second tetrahedron. A lower portion 515 of the first wire 52, connected to the common upper end 58 of the three second wires 59, 510, 511, has a first curvature, and an upper portion 516 of one of the three second wires (referenced 59 in [Fig. 5]), connected to the common upper end 58 of the three second wires, has a second curvature, this second curvature being the inverse of the first curvature. The unit cell further comprises at least one element of a thermally conductive material 517, oriented horizontally.

[0107] The elementary wire packing mesh, also called the elementary wire packing pattern, according to the invention can be defined as an elementary TS packing pattern, as described above and in Figures 1, 2, and 3, the structure of which has been modified by adding one or more horizontally oriented elements that improve the radial heat flow, such as horizontal strands, wires, or vertical plates.

[0108] The addition of horizontally oriented elements does not degrade the hydrodynamic properties of the wire packing.

[0109] The description given above of the TS elementary trimming patterns also applies to the elementary patterns according to the invention. However, unlike the patterns described in document FR-A1-3 113 610, the cross-sectional shape of the wires in the elementary patterns according to the invention can be any shape and is not limited to a polygonal shape, with at least one side of the polygon being concave and / or convex. The cross-sectional shape of the wires in the elementary patterns according to the invention can, in particular, be a circle, an ellipse, or a polygon. Furthermore, the elementary patterns according to the invention include one or more horizontally oriented elements 517 that are not present in the TS elementary patterns.

[0110] The parameters defining the elementary meshes according to the invention are therefore as follows, as shown in [Fig.1], [Fig.2] and [Fig.3]: - dw: largest dimension of the cross-section of the wires arranged along the edges of the tetrahedra, for example diameter of the wires (mm), generally the same for all wires, generally from 0.5 to 3.0 mm, preferably from 1.5 to 3.0 mm; -11: edge length in lower regular tetrahedron (mm), usually 7 to 20 mm, preferably 12 to 16 mm; -12: edge length in upper irregular tetrahedron (mm), usually equal to 11, usually from 7 to 20 mm, preferably from 12 to 16 mm; - al: angle of the tangent of the “spline” (curvature) with the vertical in the regular tetrahedron (°), generally from 30 to 40°, for example 30°; - a2: angle of the tangent of the single-strand spline (curvature) with the vertical in the irregular tetrahedron (°), generally from 30 to 50°, for example 40°.

[0111] Preferably, the angles al and a2 are different, for example a2 = al + 10°.

[0112] The horizontally oriented elements can take various forms.

[0113] According to a first embodiment of the elementary wire filling mesh according to the invention, an example of which is shown in [Fig.5], the horizontally oriented elements can be curved horizontal wires, rods or strands 517, in other words arcs, preferably concave arcs oriented upwards.

[0114] In [Fig. 5], the tangent of the arc forms an angle of 45° with the horizontal. The diameter of the wires of the horizontal strands is the same as that of the wires of the elementary motif TS arranged along three edges of tetrahedra.

[0115] In [Fig. 5], three horizontal strands 517 have been added per unit cell. Two horizontal strands are placed in the upper tetrahedron and each connect two lower vertices, respectively at the lower ends 55, 56, and 55, 57, of the wires of the upper tetrahedron, and the third is placed in the lower tetrahedron and connects two lower vertices at the lower ends 512, 513 of the wires of the Bottom tetrahedron. The horizontal strands 517 are placed so as to repeat the symmetry of the elementary unit cell.

[0116] Any other number of horizontal strands may be provided according to the invention, in particular a number of 4 or more.

[0117] Said horizontal wires, rods or strands 517 are preferably curved. They may have a larger cross-sectional dimension, for example a diameter, of between 1.5 and 3 mm.

[0118] According to a second embodiment of the elementary wire packing mesh according to the invention, examples of which are shown in [Fig.6], [Fig.7] and [Fig.8], the horizontally oriented elements can be vertical plates 61, 71, 72, 81, 82.

[0119] The vertical plates improve radial heat transfer without significantly affecting the hydrodynamic performance (capacity) of the TS geometry. The heat flow is improved due to the orientation of the vertical plates and the additional surface area. Furthermore, the vapor flow is not significantly disturbed.

[0120] The thickness, number, and positioning of the vertical plates may vary.

[0121] Generally, the thickness of the plates can range from 0.3 mm to 2 mm, in particular be about 0.5 mm.

[0122] The number of vertical plates is generally from 1 to 3, in particular 2. It is not advantageous to add more than three plates because this would clutter the geometry, create a significant pressure drop and increase the probability of premature flooding of the column packed with such elementary meshes.

[0123] In all cases, the plates are designed so as to follow the same curvature (“spline”) as the threads of the elementary motif TS.

[0124] Two types of vertical plate positioning can be distinguished.

[0125] A first type of positioning, examples of which are shown in [Fig. 6] and [Fig. 7], is positioning between two adjacent elementary loops. In other words, each plate 61, 71, 72 fills the space between two wires belonging to different elementary loops.

[0126] This first positioning is better from a hydrodynamic point of view because the plates do not add any additional obstacles to the gas flow. The gas flow is oriented laterally, but the pressure drop is not affected.

[0127] Fig. 6 and Fig. 7 show only one of the two elementary meshes.

[0128] The unit cell shown in [Fig. 6] comprises only one plate vertical 61 fixed to one of the wires 513 of the bottom tetrahedron of the elementary mesh TS, with a thickness for example of 0.5 mm, 1 mm, or 2 mm.

[0129] In the elementary unit cell shown in [Fig. 7], in addition to a first plate 71 in to the lower tetrahedron, a second plate 72, with a thickness for example of 0.5 mm, is added to the upper tetrahedron.

[0130] A second type of positioning, shown in [Fig.8], is a positioning of the plates 81, 82 between two wires of the same elementary mesh TS.

[0131] According to a third embodiment of the elementary wire packing mesh according to the invention, an example of which is shown in [Fig. 9], the elementary mesh may comprise a first additional vertical wire and / or a second additional vertical wire (this is then a "Pentaspline" (PS) elementary mesh, i.e. a 3-dimensional mesh with 5 faces, and no longer a "Tetraspline" TS)). This elementary mesh may further comprise one or more additional horizontal elements, for example in the form of arcs, as already described above with reference to [Fig. 5].

[0132] Thus, the elementary unit cell shown in [Fig. 9] comprises two regular pentahedra 91, 92 with edges formed of wires of the same length, for example 15.35 mm, and of the same diameter, for example 2.25 mm. This elementary unit cell further comprises two horizontal elements 93, 94 connecting respectively two vertices of the upper pentahedron and two vertices of the lower pentahedron.

[0133] The angle of the curves (“spline”) with the vertical axis Z is 35° for all the wires of the elementary mesh TS. This angle is chosen so that the porosity is 90%.

[0134] According to a fourth embodiment of the elementary wire filling mesh according to the invention, an example of which is shown in [Fig. 10], the horizontally oriented elements are straight, rectilinear horizontal wires, rods or strands, each supported by vertical half-plates.

[0135] This fourth embodiment is a combination of the first and second embodiments described above.

[0136] The reason for using a half-plate is that the structure is thus less cluttered and the heat flux is less dispersed. Furthermore, the change caused to the fluid flow is small because the horizontal strands are added between the wires of two adjacent TS elementary meshes.

[0137] In the embodiment shown in [Fig.10], three straight horizontal rods 101, 102, 103, supported by vertical half-plates 104, 105, 106, are added to the elementary mesh TS.

[0138] The diameter of the vertical wires of the elementary mesh TS is for example chosen at 2.25 mm, giving the elementary mesh good hydrodynamic and separation performance, as well as better wetting.

[0139] Generally, said straight horizontal wires, rods or strands may have a larger dimension than the wire cross-section, for example a diameter, from 1.0 to 3.0 mm, this larger dimension being constant or variable along the axis of the strands.

[0140] The diameter of the straight horizontal rods 101, 102, 103 is preferably equal to or less than that of the vertical wires, so as to limit the solid density of the structure and maximize its porosity. This diameter is, for example, 2 mm, which is slightly less than the diameter of the wires, strands of the elementary unit cell TS, which is, for example, 2.25 mm. Such a diameter of 2 mm also makes it possible to avoid superfluous details and troublesome points of intersection between the rods and the wires, strands.

[0141] As shown in [Fig.10], the shape of the upper half-plate 104 makes the structure slightly asymmetrical.

[0142] The thickness of the half-plates can range from 0.3 mm to 2 mm, preferably be about 0.5 mm.

[0143] In general, for each of the embodiments described here, the number, positioning and / or diameter / thickness of the horizontal strands / vertical plates or half-plates may vary.

[0144] According to a fifth embodiment of the elementary wire packing mesh according to the invention, examples of which are shown in [Fig.11], [Fig.12] and [Fig. 13], the horizontally oriented elements are made up of straight horizontal rods 111, 112, 113 extending on either side of the vertices of the tetrahedra and supported symmetrically on either side of these vertices by vertical quarter plates respectively 114 and 115, 118 and 119, 116 and 117.

[0145] On [Fig.11], [Fig.12] and [Fig.13], the elementary unit cell comprises three straight horizontal rods 111, 112, 113, namely two straight horizontal rods 112, 113 at the top of the lower tetrahedron and one straight horizontal rod 111 at the top of the upper tetrahedron.

[0146] The main difference compared to the fourth embodiment is that this geometry is symmetrical with respect to the vertical plane (XZ), as can be seen in particular in [Fig. 11].

[0147] The use of quarter-plates makes the geometry less cluttered. In addition, preferential gas flow paths are limited due to the symmetry. The quarter-plates, as shown in the figures, are preferably triangular in shape. Alternatively, they may be circular in shape.

[0148] In this configuration, generally speaking, said straight horizontal wires, rods or strands may have a larger cross-sectional dimension, for example a diameter, of 1.5 to 3.0 mm.

[0149] For example, the horizontal stems, strands 111, 112, 113 can have a diameter of 1.5 mm.

[0150] Generally, the thickness of the quarter-plates can range from 0.3 mm to 2 mm, preferably from 0.5 mm to 2 mm. The thickness of the quarter-plates can, for example The thickness should be 0.5 mm. The main role of quarter-plates is to support the rods and horizontal strands; therefore, their volume is advantageously limited, since they are quarter-plates. Another advantage of quarter-plates is the increased surface area.

[0151] A fillet 121, for example 1.5 mm in diameter, can be added between the quarter plates and the horizontal strands, as shown in [Fig. 12], for example, between the rod 113 and the quarter plates 116, 117. This fillet 121 rounds the edges between the horizontal strands and the vertical quarter plates that support them. Such fillets make the structure more aerodynamic compared to the same structure but without the fillet, shown in [Fig. 13].

[0152] As mentioned above, when describing the geometry of a conventional TS packing, this geometry does not involve a vertical repetition of the elementary motifs along the Z-axis, but along an inclined axis e3, as shown in [Fig. 14]. Each rectangle drawn in [Fig. 14] represents a conventional TS elementary motif that is periodic along X, Y and e3.

[0153] When an elementary mesh is repeated twice vertically along the inclined axis e3, and one of these meshes is rotated 180° relative to the other mesh along the Z axis, a wire packing element is created comprising the assembly of two elementary meshes arranged vertically relative to each other, one of said elementary meshes having undergone a 180° rotation about a vertical axis, as illustrated in [Fig. 15]. Each rectangle drawn in [Fig. 15] represents a wire packing element according to the invention, which is periodic along X, Y, and Z. It is a rotation of this type that is carried out in the wire packing elements according to the invention, which, however, comprise not elementary meshes TS, but elementary meshes according to the invention, comprising horizontally oriented elements.

[0154] A wire packing element according to the invention, comprising two elementary meshes according to the fifth embodiment described above, the lower mesh having undergone a rotation of 180° with respect to the Z axis, is shown in [Fig. 16]. The constituents of a first elementary mesh according to the invention (upper mesh) are observed there, in particular the horizontal strands 111, 112, 113 and the vertical quarter plates respectively 114 and 115, 118 and 119, 116 and 117, which support them; as well as the constituents of a second elementary mesh according to the invention (lower mesh), in particular the horizontal strands 111', 112', 113' and the vertical quarter plates respectively 114' and 115', 118' (the quarter plate 119' not being visible in the figure), 116' and 117', which support them.

[0155] In the embodiment shown in [Fig. 16], the lower mesh is assembled to the upper mesh by connecting a lower end 514 of a second vertical wire 52 of the second tetrahedron (lower tetrahedron) of the upper unit cell, to the upper vertex 54' of the first tetrahedron (upper tetrahedron) of the lower unit cell. Such an embodiment is in no way limiting of the invention.

[0156] To prepare the complete, final wire packing according to the invention, the wire packing elements described above are repeated until a rectangular section piece is obtained which can then be cut to obtain the final complete wire packing corresponding to the geometry of the exchange device, for example corresponding to the geometry of the column section into which the wire packing is to be integrated.

[0157] The wire filling can be produced by 3D printing.

[0158] The wire packing according to the invention can be a wire packing for a circular cylindrical concentric “HIDiC” column made up of the vertical assembly of several circular cylindrical wire packing blocks.

[0159] Fig. 17 shows one of these wire packing blocks before assembly.

[0160] The packing block 170 comprises a body 176 formed of a wire packing in accordance with the invention as described above. This body 176 is circular in shape and is defined, delimited, by an upper cross-section 171 and a lower cross-section 177 (bottom face in the representation of [Fig. 17]). The body 176 is traversed by an internal circular cylindrical vertical wall 172 extending between its upper cross-section 171 and its lower cross-section 177.

[0161] This internal cylindrical circular vertical wall, hereinafter referred to as the internal wall, 172 is shown alone in a / on [Fig. 18]. It has an upper edge 178, located at the level of the upper cross-section 171 of the body 176, and an opposite lower edge 179, located at the level of the lower cross-section 177 of the body 176. The upper edge 178 is provided with a groove 173 for receiving a sealing gasket.

[0162] The internal wall 172 has an internal face 1721 and an external face 1722.

[0163] Circular cylindrical vertical orifices 174 pass through the body 176 between the upper cross-section 171 and the lower cross-section 177. These orifices are preferably located in the inner wall 172. In the embodiment shown in the figures, they constitute the central orifice of longitudinal cylinders 180 attached to the inner wall 172, preferably on the outer face 1722 of this wall. In the particular embodiment shown in the figures, there are three of these circular cylindrical vertical orifices 174, uniformly distributed around the inner wall 172, such a number and such an arrangement not being in any way limiting of the invention.

[0164] Fig. 18 shows, in b, the packing block 170 comprising the body 176 formed by the wire packing and the internal wall 172. The latter defines an internal zone 181 of body 176, arranged inside the internal wall 172, and an external zone 182 of body 176, arranged outside the internal wall 172.

[0165] On [Fig. 17], indexes or markers 175 are shown, provided at the level of the upper edge 178 of the inner wall 172, so that, during assembly carried out by a rotation of one block relative to another block, the geometric continuity of the assembly is ensured.

[0166] The filling block according to the invention is preferably formed as a single piece, preferably by an additive manufacturing technique.

[0167] Following the manufacturing steps, a resin can be applied in the groove 173 to compensate for the roughness resulting from the manufacturing technique of the packing block, for example, additive manufacturing, and to avoid a complicated machining operation. This resin is ultimately located under the sealing gasket.

[0168] The wire packing block according to the invention can be used to manufacture the internal structure of a circular cylindrical concentric "HIDiC" column. The height constraint of such columns necessitates that they be made up of several packing blocks which must be assembled to form the column internal structure. The assembly system must be leak-proof and must not impair separation performance or increase the overall volume. The packing block 170 according to the invention advantageously meets these requirements.

[0169] The assembly of several circular cylindrical wire packing blocks 170 as described above, to form an internal according to the invention, is achieved by vertically stacking the different packing blocks one on top of the other, the upper straight section 171 of one being deposited on the lower straight section 177 of another.

[0170] Such an assembly of two filling blocks is illustrated in [Fig. 19], the filling blocks being represented there by their internal walls 172, 172' respectively.

[0171] The assembly can be secured by threaded rods 183 received successively in the vertical holes 174, 174' of the different blocks, and clamping bolts 184 mounted on these rods 183, preferably at each of their opposite ends protruding respectively from the vertical holes 174, 174'. These threaded rods 183 and the associated clamping bolts 184 ensure the pressure resistance of the assembly.

[0172] An annular sealing gasket 185, located in the groove 173 of the inner wall 174 of the lower block, is interposed between the latter and the inner wall 174' of the upper block. This sealing gasket ensures the seal of the assembly. It also provides insulation between the inner zone 181 and the outer zone 182 of the packing body 176.

[0173] Small O-ring seals 186 are further preferably interposed between the longitudinal cylinders 180, 180' of the superimposed blocks, for insulation between the vertical cylindrical circular orifices 174, 174' and the external area 182 of the packing body 176.

[0174] The clamping bolts 184 are preferably screwed onto the threaded rods 185 until they tighten and compress the various sealing rings 185 and 186.

[0175] The invention will now be described with reference to the following examples, given by way of illustration and not limitation. EXAMPLES

[0176] These examples implement filling blocks formed from: - comparative elementary wire packing meshes, not conforming to the invention, named TS-2.25-15.35-30, of tetraspline structure (TS) for which dw = 2.25mm, 11 = 15.35mm, al = 30° and a2 = 40° (packing block named TS-2.25); - or elementary wire packing units according to the invention, designated TS-3HSP-SA-1.5F, as illustrated in [Fig. 5], corresponding to the tetraspline (TS) geometry for which dw = 2.25 mm, 11 = 15.35 mm, al = 30° and a2 = 40° and comprising the following modifications compared to TS-2.25: 3 horizontal strands (diameter 1.5 mm) are each supported by a quarter plate, with a fillet between the strand and the quarter plate (3HSP), modification of the tetraspline symmetry with an alternating 180° rotation of the strands in the z-axis every 2 layers and with a mesh between the plates and the horizontal strands (1.5F). This packing unit is designated TS-HSPi.

[0177] A / Design and production of an HIDiC column based on TS-HSPi packing blocks according to the invention

[0178] Al / Design of the packing blocks

[0179] To produce the filling block, the desired mesh structure is designed using computer-aided design (CAD) software, and then an "STL" file is generated. This file is a triangular mesh describing the surface of the structure. The greater the number of triangles, the higher the resolution.

[0180] A.2 / Production of polymer filling blocks

[0181] For the production of polymer packing blocks, the "STL" structure file is opened using the NAUTA printer preprocessing software, and a document with the extension "fictor" is generated. The prepared file is loaded into an XFAB 3500PD printer. The printer is loaded with the material (e.g., Therma DM500 resin), and then the printing process is started. Once printing is complete, the produced packing block is cleaned and post-treated before experimental testing. Cleaning is carried out with either 95% ethanol or isopropanol, and then the packing block is dried. Alcohol cleaning is repeated if any residue remains. The packing block is then thoroughly rinsed under water. It is blown dry for a few seconds, then dried with an air blower and placed in a UV curing unit (DWS brand). The post-curing time is 30 minutes.

[0182] A.3 / Production of metal trim blocks

[0183] For the production of metal packing blocks, the cutting of the complex cylindrical structure in CAD software results in the formation of incomplete strands / plates and / or strands suspended from the packing edges. The structure is carefully cleaned of all peripheral elements that could disrupt packing production: elements (strands, plates) in mid-air / without support, very thin elements (thickness < 0.5 mm). The file is then generated in "STL" format and loaded into a printer (such as the GE Concept Laser M2 Cusing printer). The printer is loaded with the material (e.g., AlSi7Mgo6 powder), and the printing process is started. Next, the metal structure is depowdered and separated from the printing platform using electrical discharge machining (EDM). Finally, it is cleaned in an ultrasonic bath containing a degreasing agent.

[0184] A.4 / Assembly of the trim blocks

[0185] The TS-HSPi packing blocks according to the invention obtained are as shown in [Fig. 18]. For this example, their height is 218.7 mm (one of the blocks having a height of 109.4 mm) and their diameter is 145 mm.

[0186] For assembling the various packing blocks, as illustrated in [Fig. 19], the annular seals 185 used are 3 mm x 81 mm, and the O-ring seals 186 are 1.5 mm x 9.5 mm. The number and diameter of the threaded rods 183 are fixed at 3 and 6 mm, respectively, depending on the mechanical force required to sufficiently compress the seals. The seal material is fluorocarbon rubber (FKM), also known as Viton®, chosen for its chemical compatibility with organic mixtures (cyclohexane / n-heptane) and its resistance to high temperatures. The threaded rods 183 and the clamping bolts 184 are made of stainless steel, chosen for its chemical and mechanical resistance. The dimensional characteristics of the TS-HSPi packing blocks produced, as illustrated in [Fig. 17] and [Fig. 18], are summarized in Table 1.

[0187] [Tables 1] Dimensions Value Height of the periodic packing element 54.68 mm Maximum height of the packing block 218.7 mm Diameter of the internal zone 181 of the packing block 87 mm Diameter of the external zone 182 of the packing block 145 mm Thickness of the internal wall 172 1.5 mm Variation range of the diameter of the internal zone 181 of the packing block (varied to accommodate the groove 173) 87-74.8 mm for a height of 29.7 mm Number and diameter of threaded rods 183 3x6 mm Internal and external diameter of the cylinders 180 receiving the threaded rods 183 7.5 mm / 10.5 mm Thickness and diameter of the annular seals 185 3 mmx81 mm

[0188] Table 1 - Dimensions of a TS-HSPi packing block according to the invention

[0189] 9 such filling blocks are assembled to form the column. The mesh Since the TS-HSPi packing is symmetrical and vertically periodic, the strands of the nine packing blocks align well and form a perfectly continuous packed column approximately two meters high (1.9683 m). Visual observation confirms that the liquid flow is well distributed within the packing. The rotation integrated into this structure ensures adequate mixing of the fluids.

[0190] Three groups of experiments were implemented to compare different prior art technologies with the technology according to the invention: a numerical study to evaluate the pressure drop and thermal efficiency with a gas flow (single-phase model), an experimental study of the hydrodynamic performance and the capacity and separation efficiency of the packings without an internal wall (Experimental Study 1), and finally an experimental study to evaluate the heat transfer performance and all combined performance in the HIDiC column with metal packing blocks equipped with an internal wall (Experimental Study 2).

[0191] B / Numerical Studies and Experimental Study 1

[0192] B. 1 / Numerical study protocols

[0193] B. 1.1 / Convection Model

[0194] For the numerical study, a domain of a semi-cylinder with an external diameter of 90 mm and a height between 200 and 230 mm, containing the solid and fluid (gas) parts, was used. The solid part consisted of the internal structure under study and a peripheral external wall, to which it is attached, with a thickness of 2 mm. The model The turbulence model chosen for this study was the kw-SST model from Ansys Fluent 2020 A1 software, along with its associated wall laws. Liquid inlet was located at the bottom of the domain, and outlet at the top. At the inlet, the fluid temperature was set to 70 °C, and the gas velocity was set between 0.8 and 2.8 m / s, corresponding to a turbulent regime, with a Reynolds number (Re) between 7000 and 28000. A flow establishment zone with a height of 100 mm was adopted upstream of the packing, and a void zone of 20 mm was adopted downstream. A symmetry condition was applied to the XZ plane, and a heat flux of 5 kW / m² was applied to the external wall surface.

[0195] Using this model, the pressure drop dP / dzsec generated by the dry packing (gas flow only) was evaluated, and the average thermal conductance of the packing, hA, due to convection in the fluid and solid and conduction in the solid (wall and packing), was estimated (conjugate heat transfer). The convergence of the variables, mesh independence, and independence from the domain size (packing height) were verified and confirmed before estimating each quantity.

[0196] B. 1.2 / Conduction model

[0197] Another, simpler model for studying conduction, effective thermal conductivity (ETC), through the packing, was used. In this model, a parallelepiped domain containing the packing structure under study was designed. This domain was partitioned to have an integer number (2, 3, or 4) of unit cells in each direction (X, Y, Z). Conduction was studied in the three directions X, Y, Z. For each direction, the effective thermal conductivity (ETC) was evaluated by imposing a temperature difference of 2°C between two planes of the packing that are opposite and perpendicular to the direction under study (planes referred to as the hot and cold planes, respectively). In this model, there is no flow; the fluid is static.

[0198] B.2 / Experimental Study Protocol 1

[0199] For the following experimental tests, two packing columns were printed in polymer and experimentally tested for their separation capacity and hydrodynamic performance. These are the TS-HSPi packing according to the invention, made of polymer without the inner wall, and the TS-2.25 packing not according to the invention, of the same dimensions. Comparative tests were also carried out with a molded metallic foam without an inner wall. This foam has Kelvin cells (85% theoretical porosity) and will be abbreviated as KC-P85.

[0200] Two experimental pilot plants were used to evaluate hydrodynamic performance (head loss, wetting, liquid distribution, flow, capacity) and separation performance (equivalent height of a theoretical HEPT plate, capacity - gas factor at the point of congestion (Fengorgement).

[0201] B.2.1 / Hydrodynamic pilot

[0202] The hydrodynamic pilot consists of a column 150 mm in diameter and 2 m high, of which 1 m is filled with the packing material under study and 1 m is empty to allow flow establishment. The packed packing is 145 mm in diameter and consists of several blocks stacked vertically to form 1 m of packing. A Keller Series 30 differential pressure transmitter with a digital pressure indicator (EV-120) measures the pressure difference, providing a high-precision measurement of ±0.01%. The pressure drop is recorded using ControlCenterSeries30 (CCS30) data acquisition software. Pressure sensors are positioned at the inlet and outlet of the packing. Two experiments were conducted using this pilot.

[0203] The first experiment is carried out with a gas flow alone, air at ambient temperature and atmospheric pressure. The aim is to measure the dry pressure drop profile for the loaded packing. The dry pressure drop profile is recorded for approximately twenty air flow rate values, ranging from the 100 to 300 m³ / h graduations of the flow meter, which correspond to different gas velocities between 0.5 and 3 ms*.

[0204] The second experiment analyzes the pressure drop with a counter-current flow of gas and liquid. Pressure drop profiles are measured for three different liquid flow rates (water at ambient temperature): 162, 270, and 378 L / h (9.2, 15.3, and 21.4 m³ / m² / h). For each liquid flow rate, the air flow rate is increased from 100 Nm³ / h (flowmeter graduation) in increments of 10 m³ / h up to the flooding points, corresponding to the maximum air flow rate of the flowmeter, 300 Nm³ / h. The visual signs, bubbling and liquid entrainment, as well as the exponential increase in pressure drop, define the packing flooding point, which indicates its separation capacity at a specific liquid flow rate.

[0205] For each air flow rate value, the pressure drop dP / dz is recorded every second for 6 min, as the countercurrent flow requires more time to stabilize. Before starting the gas / liquid countercurrent experiments, the column is irrigated with the maximum liquid flow rate and a high air flow rate close to flooding, allowing adequate wetting of the packing.

[0206] B.2.2 / Mass transfer pilot

[0207] The experimental mass transfer apparatus consists of a glass distillation column with a diameter of 150 mm and a packing height of 1 m, a reboiler integrated into a flask at the bottom of the column, and a vertical total condenser at the top of the column. The reboiler heats and vaporizes the binary mixture using a A steam-fed coil is filled with a standard binary mixture of cyclohexane and n-heptane, containing approximately 20% cyclohexane by mass. The pressure drop is measured between the top and bottom of the packing section. By setting the heating power at the reboiler, a pressure difference (dP) is established, and a gas loading factor (F) is calculated. This separation is carried out in a distillation column operating under total reflux, meaning that neither the upper (distillate) nor lower products are discharged or removed.

[0208] Four to six further measurements with F between 0.8 PaO₅ and 0.8 x Fflooding are performed after steady state is reached, as ensured by the temperature measurement at the top and bottom of the column and the condensate flow rate, indicating the heating power. For each F value, several samples of the products from the top and bottom of the column are collected to determine the mixing density, which is correlated with the mixture composition. For each experiment (F value), the HEPT (equivalent height of a theoretical plate) is determined by examining the binary liquid-vapor diagram of the cyclohexane / n-heptane mixture under atmospheric pressure. The Wilson model is the thermodynamic model chosen to calculate the V / L equilibrium curve.

[0209] B.3 / Results

[0210] The experimental and numerical performances of the three packings studied are summarized in Table 2.

[0211] [Tables2] Packing Performance KC-P85 TS-2.25 TS-HSPi Geometric Exp. Porosity e (%) 82.9% 89.6% 86.4% As (m 9 291 176 245 Hydrodynamic Exp. dP / dzsec (mbar / m) @ F=2 Pa0 5 8.49 0.82 1.19 Separation Exp. F fPa0'5) 1.1 2.5 2.6 HEPT(m) 0.27 0.37 0.38 Thermal Num. ETChor (W / m / K) 11.9 3.0 6.0 hA (W / K) @ F=1.6 Pa05 348 111 194

[0212] Table 2 - Performance of the different packings - where As = specific geometric surface area; dP / dzsec (mbar / m) = dry pressure drop of the packing; Fengorgement = gas factor F at the flooding point (F = gas velocity multiplied by the square root of the gas density); HEPT = equivalent height of a theoretical plate; ETC hor = effective thermal conductivity in the horizontal direction; hA = thermal conductance; Exp. = experimentally measured values; Num. = calculated values ​​nu- metrically according to the numerical study protocols

[0213] It is observed that the packing block according to the invention TS-HSPi has the same efficiency and separation capacity as the packing block TS-2.25 (Fengorgement and HEPT), and increases the heat transfer efficiency (hA) by 75% compared to TS-2.25 according to the simulation. Its specific geometric surface area is 38% greater than that of the packing block TS-2.25. Moreover, thanks to its vertical periodicity, its separation efficiency is stable over the entire range of gas loading factor F, which demonstrates good liquid and gas distribution over the entire cross-section and column height of the packing according to the invention, unlike other structured packings available on the market or studied here. The packing according to the invention TS-HSPi also generates dry pressure drops comparable to those of the comparative packing TS-2.25.The KC-P85 packing is very efficient in heat transfer, according to the numerical study, but very limited in separation capacity. It also generates a huge pressure drop, according to Experimental Study 1.

[0214] C / Experimental study 2

[0215] This experimental study is carried out with the metal packing according to the invention, with an internal wall, in order to evaluate and compare, on the one hand, its heat transfer performance, and on the other hand, its overall performance in the HIDiC pilot. The comparison is made primarily with the KC-P85 metal (aluminum) packing produced for molding with an internal wall.

[0216] Separation and energy gain performance were evaluated for concentric HIDiC columns of 150 mm diameter and 1 m height for the heat transfer performance experiment or of 2 m height for the experiment covering all performance combined, and whose internals are formed, as described above, by assembly of packing blocks respectively: - TS-HSPi, according to the invention, as described in the previous example, but comprising an internal wall 172 of average thickness 1.9 mm (1.5 mm excluding the assembly area), - KC-P85, not in accordance with the invention, in which the padding is a complex structure of metallic foams based on the Kelvin cell, with an internal wall 172 of 5 mm thickness, - SSR, not in accordance with the invention, in which the lining is formed of bulk super Raschig rings, with a free internal wall (not integral with the lining) of 5 mm thickness.

[0217] Each column comprises two zones separated by a central wall formed by the internal walls 172 of the stacked packing blocks, namely an internal zone, formed by the packing located inside the central wall, and an external zone, formed by the packing located outside the central wall.

[0218] C. 1 / Heat transfer performance

[0219] For each column, in the outer zone, water vapor circulates at a specific pressure (boiling point) and condenses on the packing and the central wall. In the inner zone, a pure chemical enters the liquid state at a temperature close to its boiling point and is partially vaporized by heat from the outer zone (water vapor) and exchanged through the entire assembly (central wall and packing). The vapors in the inner zone are condensed at the top of the column and measured to calculate the heat exchanged. These measurements allow the determination of the overall normalized thermal conductance (UAexpnormen W / K) as a function of the vapor fraction in the inner zone.

[0220] Two organic products were tested for SRR (n-Butanol and n-Heptane) and one for each complex structure: n-Butanol for KC-P85 and n-Heptane for TS-HSPi.

[0221] The measurements carried out lead to the conclusion that the heat exchange for the KC-P85 and TS-HSPi monoblocks is significantly more efficient than for the SRR, which has a free wall that creates thermal bridges with the loose packing. Under the same operating conditions, the TS-HSPi structure according to the invention achieves the same level of thermal performance as the KC-P85.

[0222] Such good thermal performance of the TS-HSPi column according to the invention is achieved thanks to: - a low thickness of the central wall (on the order of 1.9 mm), possible thanks to additive manufacturing; - the presence of horizontal strands promoting thermal conduction from the internal zone to the external zone; - a streamlined shape of TS-HSPi which promotes good contact with fluids (wetting ratio), generating good heat transfer by conduction and convection.

[0223] C.2 / Overall performance

[0224] Hereinafter, for the HIDiC columns implemented (column with internals formed of TS-HSPi packing blocks according to the invention and column with internals formed of KC-P85 packing blocks not according to the invention), the internal zone, playing the role of rectification zone, is hereinafter referred to as InCo and the external zone, playing the role of annular exhaustion zone, is hereinafter referred to as ExCo.

[0225] The operation applied to the columns is as follows.

[0226] The fluid, consisting of a mixture of cyclohexane and n-heptane with 50% cyclohexane by mass, stored in a 100-liter feed tank, is pumped, heated, and admitted to the top of the ExCo. It is distributed over the packing in the ExCo using a ring distributor. At the bottom of the ExCo, a reboiler generates steam from the fluid, which rises to the top of the ExCo. The steam is then sent by a compressor to the bottom of the InCo.

[0227] The pressure difference between the two zones, generated by the compressor, results in a temperature difference. A check valve ensures that the vapor flow in the compressor and its recirculation line is in only one direction. The InCo is subjected to a higher pressure / temperature; therefore, heat transfer occurs from the InCo to the ExCo via the central column wall and the packing. This results in condensation in the InCo and vaporization in the ExCo. The liquid falling from the condenser passes through a reflux system that sends the liquid either to the distillate tanks or back into the InCo (reflux). The liquid reflux is returned by a distributor and mixes with the condensate that forms on the InCo packing (due to heat exchange). Both liquids are collected at the bottom of the InCo and conveyed to the top of the ExCo, thanks to the pressure difference between the two zones.The excess fluid at the reboiler flows by gravity to the lower product tank (called residue).

[0228] The pressure in the InCo is kept stable by the admission or discharge of nitrogen via two valves that can be controlled by a regulator. The pressure in the ExCo is controlled by the compressor frequency. The heat exchanged between the two zones reduces the need to supply a large amount of heat to the reboiler. Consequently, this column configuration is considered less energy-intensive than a conventional distillation column and more advantageous from an environmental and economic standpoint. A flow of nitrogen admitted into the ExCo ensures an inert atmosphere inside the pilot, thus reducing the risk of fire or explosion. The pilot is equipped with six control loops that maintain steady state. These control loops address: feed temperature, ExCo pressure, InCo pressure, ExCo pressure drop, reflux ratio, and liquid level at the bottom of the InCo.

[0229] Tables 3 to 7 present the operating conditions and test results for the KC-P85-based column not according to the invention (2 tests, named 1k and 2k) and for the TS-HSPi-based column according to the invention (5 tests, named 1, 2, 4, 5 and 7), more specifically: - Table 3: tests under variable operating conditions (feed flow rate F, cyclohexane (C6) composition wEjC6, internal zone pressure Pin, external zone pressure drop dPEx, flow distribution between distillate and background products D / F:W / F. Other operating conditions are unique for all tests, no reflux, pressure in the external zone PEx=1.01 bar, and temperature at the inlet of the external column TF=85°C); - Table 4: Separation efficiency (mass flow rates of distillate D and residue W, purities (mass fraction of C6) wC6,d and wC6,w, recovery rate of C6 in distillate Tc6,d, recovery rate of n-heptane (C7) in residue rC7,w, and factor of SPF separation performance. SPF is a mathematical indicator and is calculated as the geometric mean of wC6,f, wC6,d, wC7.w- ^c6,d and rC7,w- H (allows comparison of the separation performances of different experiments); - Table 5: Performance indicators of capacity and heat transfer efficiency (mass flow rate at the top of the external zone F' (F+Ll), mass flow rate VI', and mass fraction wC6,vi' of vapor at the bottom of the internal zone (also at the top of the external column), flow rate Ll, and mass fraction wC6,li of liquid at the bottom of the internal zone, gas loading factor FlnCOjbOt calculated at the bottom of the internal zone, according to equation 1:

[0230] [Math.l] VT SlnCo P g (Equation 1)

[0231] where VI' is the mass flow rate of vapor at the bottom of the inner zone (also at the top of the outer column), pg is the density (mass density) of vapor at the bottom of the inner zone and SlnCo is the minimum cross-section of the inner zone (equal to jr(Dmin>lnCo / 2)2). The minimum diameters of the inner zone Dmin>lnCo are 80 mm and 74.8 mm for KC-P85 and TS-HSPi, respectively); - Table 6: energy consumption (reboiler energy Qb, pilot heat losses Qioss, heat exchange between internal and external zones QEx, and calculated compressor power requirement with an isentropic efficiency rate of 25%, W COmp,25%, the last is estimated using the steam flow rate and the pressures upstream and downstream of the compressor); - Table 7: Energy gain (HIDiC energy consumption at the reboiler QbjHiDic (Qb-Qioss), RDC reflux ratio and minimum energy consumption QbjDc of the typical distillation column with the same separation specifications, and percentage energy saving. QbjDc is calculated using the commercial simulation software ProSim, and the percentage energy saving is calculated according to equation 2:

[0232] [Math.2] r- . Economy deneoe = 1 - -—!—--------- (Equation 2).

[0233] [Tables3] Column TS-HSPI KC-P85 Test No. 1 2 4 5 7 1k 2k F (kg / h) 11.8 18.5 12.0 20.5 17.4 11.0 10.5 Wc6,F 0.48 0.46 0.47 0.49 0.50 0.49 0.42 Pin (mbar) 1.25 1.25 1.30 1.31 1.35 1.50 1.50 dPEx (mbar) 0.569 0.581 0.553 0.612 0.640 1.241 1.239 D / F:W / F (%) 50:50 41:59 41:59 46:54 50:50 49:51 35:65

[0234] Table 3 - Variable operating conditions of the tests

[0235] [Tables4] TS-HSPI KC-P85 Column Test No. 1 2 4 5 7 1k 2k D (kg / h) 6.0 7.5 5.0 9.4 8.7 5.4 3.7 Wc6,D 0.75 0.79 0.82 0.78 0.78 0.79 0.87 ^06.0 (%) 79 70 72 73 78 78 72 W (kg / h) 5.9 11.0 7.0 11.1 8.7 5.6 6.9 Wc6,W 0.20 0.23 0.22 0.24 0.22 0.22 0.18 ^C7,W (%) 76 84 86 80 78 79 92 SPF (%) 71 70 71 70 72 72 72

[0236] Table 4 - Separation efficiency

[0237] [Tables5] TS-HSPI KC-P85 column Test No. 1 2 4 5 7 1k 2k F' (kg / h) 16.9 26.0 18.4 28.6 27.1 19.7 18.4 VI' (kg / h) 11.1 15.0 11.4 17.4 18.4 14.0 11.6 Wc6,Vl 0.64 0.67 0.66 0.66 0.65 0.65 0.65 FInCo,bot (Pa0'5) 0.40 0.55 0.42 0.64 0.67 0.45 0.37 L1 (kg / h) 5.1 7.5 6.4 8.0 9.7 8.66 7.90 Wc6,Ll 0.50 0.54 0.54 0.53 0.53 0.56 0.55

[0238] Table 5 - Heat transfer capacity and efficiency

[0239] [Tableauxô] TS-HSPI KC-P85 Column Test No. 1 2 4 5 7 1k 2k Qb (kW) 2.07 2.25 1.75 2.22 2.37 1.27 1.45 Qioss (kW) 1.41 1.41 1.21 1.21 1.41 0.72 1.00 Qex (kW) 0.48 0.71 0.62 0.76 0.93 0.83 0.76 Wcomp.25% (kW) 0.087 0.118 0.107 0.169 0.199 0.208 0.171

[0240] Table 6 - Energy Consumption

[0241] [Tables?] TS-HSPI KC-P85 Column Test No. 1 2 4 5 7 1k 2k Qb.HIDiC (kW) 0.66 0.84 0.54 1.01 0.96 0.55 0.45 Rdc 1.03 1.45 1.61 1.19 1.13 1.27 2.29 Qb,Dc (kW) 1.20 1.83 1.29 2.06 1.84 1.21 1.21 Energy Savings (%) 38 48 50 43 37 37 49

[0242] Table 7 - Energy Gain

[0243] No experiments have been conducted at the same pressure differential for the TS-HSPi and KC-P85 columns. However, it is possible to compare the two technologies using tests No. 5 and No. 7 for the TS-HSPi technology and No. 1k for the KC-P85 technology. These tests yield similar SPF values, comparable recovery rates, and purity, indicating comparable separation efficiency. Furthermore, these columns exhibit a similar flow rate distribution between the distillate and the bottoms, approximately 50:50. TS-HSPi achieves similar separation efficiency with a feed rate twice that of KC-P85. Both technologies offer similar energy savings, on the order of 40%. However, by increasing the pressure / temperature differential to 0.5 bar, the packing according to the TS-HSPi invention could achieve better separation efficiency and higher energy savings.This can be explained by the high condensate flow rate (Ll) observed during the transition state, which indicates a higher exchange rate.

[0244] The high capacity of the TS-HSPi column was demonstrated in the hydrodynamic and HETP results, F=2.6 Pa. In the HIDiC experiments, the highest value The gas loading factor F is 0.67 PaO5 in Experiment No. 7 for the TS-HSPi column, compared to 0.45 PaO5 for the KC-P85 column. This is 74% away from the flooding point of the TS-HSPi column. The experimental setup did not allow for the separation of a higher feed flow rate. Operation under optimal packing conditions, at 60% of the flooding point, is expected to maintain or slightly increase the energy savings rate. Indeed, increasing the vapor and liquid flow rates would improve heat exchange.

[0245] In conclusion, several experiments using HIDiC columns have demonstrated that the separation efficiency of TS-HSPi is at least as high as that of KC-P85. Furthermore, the separation capacity is at least doubled for the TS-HSPi packing according to the invention. TS-HSPi offers equivalent energy savings of 40% despite the application of a lower pressure differential than KC-P85 (a difference of 0.35 bar versus 0.50 bar for KC-P85).

Claims

Demands

1. Elementary wire packing unit of a thermally conductive material, for a gas-liquid exchange apparatus, comprising three first wires (51, 52, 53) including a common upper end (54) located at the upper vertex of a first irregular tetrahedron, said three first wires (51, 52, 53) each extending vertically from said first upper end (54), along three edges of the first tetrahedron, to three lower ends (57, 55, 56) located at the three lower vertices of a base triangle of the first tetrahedron, a lower end (55) of one of said three first wires (52) being connected, to a common upper end (58) of three second wires (59, 510, 511) located at the upper vertex of a second regular tetrahedron, said three second wires (59, 510, 511) each extending vertically from said upper extremity (58), along three edges of the second tetrahedron,up to three lower extremities (514, 512, 513) situated at the three lower vertices of a base triangle of the second tetrahedron; a lower portion (515) of said first wire (52) connected to the common upper end (58) of the three second wires (59, 510, 511) having a first curvature, and an upper portion (516) of one of the three second wires (59) connected to the common upper end (58) of the three second wires (59, 510, 511) having a second curvature, inverse of the first curvature; and the elementary unit cell further comprising at least one element of a thermally conductive material oriented horizontally.

2. Elementary mesh according to claim 1, wherein said horizontally oriented element connects two of said first wires (51, 52, 53) and / or two of said second wires (59, 510, 511), preferably two lower ends (55, 56, 57) of said first wires and / or two lower ends (512, 513, 514) of said second wires, and / or said horizontally oriented element (517; 111, 112, 113) can be capable of connecting one of said vertices with a vertex, located at the same height, of another elementary mesh.

3. Elementary mesh according to claim 1 or 2, wherein said horizontally oriented element is selected from straight horizontal wires, curved or rounded horizontal wires also called arcs (517), vertical plates (61, 71, 72, 81, 82), straight horizontal wires (101, 102, 103) each supported by half- vertical plates (104, 105, 106), and straight horizontal wires extending on either side of the vertices of the tetrahedra (111, 112, 113) and supported symmetrically on either side of these vertices by vertical quarter plates (114, 115, 118, 119, 116, 117).

4. Wire packing element comprising the assembly of two elementary meshes according to any one of claims 1 to 3 superimposed vertically, one of said elementary meshes having undergone a rotation of 180° with respect to a vertical axis.

5. Wire packing comprising the assembly of several wire packing elements according to claim 4.

6. A method for preparing a wire packing according to claim 5, characterized in that the wire packing is manufactured by an additive manufacturing technique, preferably by a laser melting technique.

7. Filling block (170) comprising a body (176) formed of a wire filling according to claim 5, said body (176) being of circular cylindrical shape and being defined by an upper straight section (171) and a lower straight section (177), and being traversed by an internal circular cylindrical vertical wall (172) extending between said upper straight section (171) and said lower straight section (177) and having an upper edge (178) at the level of said upper straight section (171), circular cylindrical vertical orifices (174) traversing said body (176) between said upper straight section (171) and said lower straight section (177), and said upper edge (178) of said internal circular cylindrical vertical wall (172) being provided with a groove (173) intended to receive a sealing gasket (185).

8. Filling block (170) according to claim 7, wherein a resin is further placed in the groove (173) to compensate for roughness, due for example to additive manufacturing and to avoid a complicated machining operation.

9. Internal for a concentric cylindrical circular “HIDiC” column, consisting of the vertical assembly of several packing blocks (170) of circular cylindrical shape according to any one of claims 7 or 8, a sealing gasket (185) being placed in the groove (173) of at least one of said packing blocks (170), and the assembly being secured by threaded rods (183) passing through said packing blocks (170) and placed in the circular cylindrical vertical orifices culars (174) of each of said packing blocks (170), and of clamping bolts (184) mounted on said threaded rods (183).

10. Gas-liquid exchange apparatus comprising a wire packing according to claim 5.

11. Gas-liquid exchange apparatus according to claim 10, which is selected from distillation columns, absorption columns, stripping columns and heat exchangers.

12. Column with an internal thermal coupling comprising an internal according to claim 9, and an external cylindrical vertical wall inside which said internal is disposed.

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