FR2740053A1 - Device for distributing, mixing, injecting and/or extracting fluids - Google Patents

Abstract

Device for distributing, mixing, injecting and/or extracting a number of fluids where there is a principal fluid A and at least one first secondary fluid B1 and a second secondary fluid B2. The device contains means to collect the principal fluid A which are connected to at least one mixing chamber, at least one primary injection and/or extraction circuit for the first secondary fluid B1 and a second injection and/or extraction circuit for the second secondary fluid B2. These circuits connect to the mixing chamber through one or more openings allowing the (B1 and B2) fluids to pass into or out of the chamber. The mixing chamber has at least one inlet for the principal fluid and at least one outlet. The device also contains means of redistributing the fluid from the mixing chamber. The injection and/or extraction circuits are distinct and placed near the mixing chamber at at least one of the chamber walls with a direction parallel to the axis of the device. Column allowing the separation of a fluid containing several separable components, comprising at least a first and second bed of solid granules separated by at least one of the above devices.

Description

 The present invention relates to a device, or abbreviated to DME, and to a method making it possible to distribute, mix, add and / or withdraw several fluids, at least one main fluid and at least two other secondary fluids.

 It finds in particular its application in the field of chromatography for fluids in the gaseous, liquid or even supercritical state.

 When the separation processes by distillation are not effective, it is possible and usual to use simulated moving bed systems, to separate the bodies comprising for example several different chemical compounds or bodies comprising isomers.

 Thus, the device according to the present invention, hereinafter abbreviated as DME, is arranged, for example, advantageously in a column comprising several beds of granular solids, between two of these beds for example. Its function is in particular to distribute or collect over the entire section of the column any fluid added or withdrawn. It also serves to remix the fluid circulating in the beds of granular solids when no other secondary fluid is added or withdrawn.

 Chromatography processes generally use several fluids called secondary fluids to distinguish them from the main fluid or body to be separated, circulating in the chromatography column.

 These secondary fluids can be of different nature and be withdrawn from the column or even injected for example at the level of the DME.

 This difference in nature leads, for example, to risks of pollution of one fluid towards the other requiring additional rinsing operations when the injection and / or withdrawal circuit is common to the secondary fluids.

 In addition, during chromatography, at the end of the drawing off operation of a first fluid, there remains a plug or residue of this fluid which it is necessary to remove before drawing off and / or injecting. a second fluid.

 For this, a preliminary operation consists in pushing or withdrawing this residue from the column.

 The rinsing operations usually carried out to clean the circuits and / or purge them contribute to increasing the complexity of the stages of the process implemented in the cobnne, its cost and its yield.

 Different distribution systems or DMEs are described in the prior art and also used at the industrial stage for fine chemistry, the laboratory or large industry.

 For example, the distributors of the company AMICON, and those described in patents US-A-3,948,775, US-A-3,214,247 and US 3,723,072. However, none of these devices describes or suggests the use of several injection and / or withdrawal circuits "dedicated" to a fluid, that is to say used for a predetermined fluid, thus making it possible to overcome the aforementioned drawbacks.

 The word "dedicated" is used in the context to mean that a circuit will see the passage only of a fluid, during the implementation of the process.

The present invention is an improvement on the applicant's previous request
WP-95/03867, where the possibility of having several injection and / or withdrawal circuits of secondary fluids positioned above the mixing chamber is mentioned. Such an arrangement is well suited for a number of secondary fluids in the column at most equal to two. However, it is less suitable for the use of more than two secondary fluids, injected and / or withdrawn from the column, due in particular to the complexity of distribution of the conduits connecting the injection and / or withdrawal chambers with the outside.

 Furthermore, during an injection and / or withdrawal operation, it is preferable for the injected and / or withdrawn fluid to arrive simultaneously at any point in the mixing chamber or chambers, which is not possible when there is a plug or residue of a fluid having a different nature in one of the conduits.

 Likewise, mechanically such an arrangement results in limiting the size of the injection and / or extraction circuits when this number of fluids is greater than four.

 Advantageously, the DME according to the invention offers an appropriate arrangement of the injection and / or withdrawal chambers and of the mixing chamber whatever the number of secondary fluids injected and / or withdrawn from the column.

 In addition, in chromatography operations, it is important to make the propagation of the main fluid in the column as uniform as possible by obtaining a piston-type flow. One of the means to achieve this is to minimize the differences in travel time, between the different fluid flow lines, or between the different particles of fluids, before they enter the mixing chamber. Indeed, these flow lines will have different lengths of travel and travel times depending on the position they occupy with respect to their circulation path inside the column, this path being for example referenced by relative to the axis of the column (or relative to one of its walls), and to the position of the mixing chamber, more particularly of the opening of the chamber allowing the passage of fluids.

 For example, when the mixing chamber is arranged substantially in the center of the column and its opening in the vicinity of the central axis of this column. the travel time for a line of fluid flowing in the vicinity of the outer wall of the enclosure is greater than the travel of a flow line flowing in the vicinity of the center of the column.

 These differences in travel time induce shifts in the arrival of the flow lines in the mixing chamber which can cause disturbances at the advancement front of the main fluid. This non-homogeneity in the instants of arrival can affect the quality of the mixture produced in the chamber, and moreover disturb the various propagation currents of the main fluids advancing or propagating in the form of "piston".

 Thus, the present invention relates to a device making it possible to distribute, mix, inject and / or withdraw several fluids, one of the fluids being a main fluid A1, and at least a first secondary fluid B1 and a second secondary fluid B2, the device comprising means for collecting the main fluid A1, the means for collecting being connected with at least one mixing chamber, at least one first injection and / or withdrawal circuit of a first secondary fluid B1, and at at least a second injection and / or withdrawal circuit of a second secondary fluid B2, the injection and / or withdrawal circuits being in communication with the mixing chamber using one or more openings allowing the passage of secondary fluids in the mixing chamber, the mixing chamber comprising at least one inlet and one outlet.

 It is characterized in that the injection and / or drawing-off circuits are distinct and arranged near the mixing chamber along at least one of its walls which has a direction substantially parallel to the axis of the DME.

 According to one embodiment of the DME according to the invention, the separate injection and / or withdrawal circuits are, for example, arranged one above the other and on the same side of the mixing chamber.

 The injection and / or withdrawal circuits are arranged along at least one of the walls of the periphery of the mixing chamber. According to a preferred embodiment of the device according to the invention, the independent injection and / or withdrawal circuits are arranged on either side of the mixing chamber, for example according to two opposite side walls.

 The number of injection and / or withdrawal circuits is at least more than four.

 Advantageously, at least one of the injection and / or withdrawal circuits is associated with at least one injection and / or withdrawal precircuit.

 One of the injection and / or withdrawal circuits are associated with an injection and / or withdrawal pre-circuit.

 The injection and / or extraction circuits and the injection and / or withdrawal pre-circuits communicate for example with the mixing chamber or with one another through one or more orifices arranged along the walls of the different chambers or of the different circuits so that the axes of the orifices are offset from each other.

 The device according to the invention may include collection means and / or redistribution means, the shape of which is adapted to minimize the differences in travel times of the fluid lines before the mixing chamber and / or after this chamber, up to at a point downstream of the chamber.

 The collection means comprise for example a collection grid extending substantially over the entire section of the DME and / or a collection space, at least one of these elements having a shape adapted to minimize the differences between the times of travel of the different main fluid flow lines before entering the mixing chamber and / or the redistribution means comprise at least one redistribution grid and / or extending substantially over the entire section of the DME.

The redistribution means comprise, for example at least one redistribution grid and / or a redistribution space which extends for example substantially over the entire section of the
DME, at least one of these elements having a shape adapted to minimize the differences between the travel times of the different flow lines of the main fluid after leaving the mixing chamber.

 The invention also relates to a column allowing the separation of a body from a fluid comprising at least several separable compounds, comprising at least a first and a second bed of granular solids separated by a DME, the DME comprising means for collection of the body to be separated, the collection means being in relation to at least one mixing chamber, at least a first circuit for introducing and / or withdrawing a first secondary fluid B1 and at least a second injection circuit and / or withdrawal of a second secondary fluid B2, the injection and / or withdrawal circuits being in communication with the mixing chamber using one or more openings allowing the passage of the secondary fluids B1 , B2 to or from the mixing chamber, the mixing chamber comprising at least one inlet and one outlet.

 It is characterized in that in the injection and / or withdrawal circuits are distinct and arranged near the mixing chamber along at least one of its walls which has a direction substantially parallel to the axis of the DME.

According to a particular embodiment, the column comprises at least four independent injection and / or withdrawal circuits arranged along at least one of the walls of the
mixing chamber, the wall of the chamber having a direction substantially parallel to the axis of the column.

It is also possible to equip the DME with collection means and / or means of
redistribution having a suitable form to minimize the differences in travel time of
differences in fluid lines that have passed through at least part of a bed of granular solids before
their entry into the mixing chamber and / or homogenize the travel times of the lines of fluids coming from the mixing chamber until they enter the second bed disposed downstream of the
DME.

 The column comprises several EMRs positioned according to one of the sections of the column and arranged one next to the other.

The conduits for injecting one or more secondary fluids B1 at a
injection and / or withdrawal chamber dedicated to this fluid are connected inside said column to
a main duct passing through at least one of the walls of the column.

Thus, the advantages offered by the DME according to the invention are in particular the following:
the independence of the injection and / or withdrawal circuits for secondary fluids allows
to avoid possible pollution phenomena and operations to purge the remainder
of fluid inside usually common conduits,
the appropriate form of collection means and / or redistribution means allows
improve the propagation of fluid fronts in the column by minimizing the differences in
travel times of the various fluid lines downstream of the DME or upstream, which allows
to obtain a piston type flow,
to minimize dead volumes by an appropriate choice of forms of collection spaces,
back-mixing phenomena, as well as pressure losses, which can adversely affect the
separation of bodies carried out in the area upstream of this EMR is minimized due to the
appropriate choice of passage openings and their distribution
it induces as low a pressure drop as possible for the circulation of the main fluid at
across the column.

Other characteristics and advantages of the method according to the invention will appear on reading the description given below, by way of illustration and in no way limiting, with reference to the appended drawings in which FIGS. 1, 2 and 3 schematize a DME according to the invention comprising two circuits
injection and / or withdrawal of secondary fluids,
Figures 4, 5 and 6 show a possibility for distributing the injection pipes and / or
extraction of secondary fluids forming part of the injection and / or withdrawal circuits,
Figures 7 and 9 show two examples of EMR according to the invention comprising three and five
independent injection and / or withdrawal circuits,
FIG. 8 diagrammatically shows an example of DME comprising four injection circuits and / or
withdrawal as well as the distribution of associated conduits,
FIG. 10 shows an alternative embodiment of the DME for which the different circuits
injection and / or withdrawal of secondary fluids are positioned on the same side of the
mixing chamber,
Figures 11, 12, 13 and 14 show examples of distribution of injection lines
and / or racking depending on the number and position of the chambers in the column,
Figures 15 and 16 show respectively a sectional view and a top view of a
EMR comprising pre-chambers associated with injection and / or withdrawal chambers
secondary fluids,
Figures 17, 18, 19 show different variants of the arrangement of injection chambers
and / or racking and associated pre-chambers,
Figures 20, 21, 22 and 23 show an example of DME in which the collection means
have a suitable shape to reduce the differences in travel time between
different fluid lines.

FIG. 1 describes an exemplary embodiment of a column 1 comprising an orifice D making it possible to introduce a main fluid A1 and an orifice E situated at the opposite end of the introduction orifice D. These two orifices E and D are preferably located along the main vertical axis of the column or horizontal when the device is used in a horizontal position. Inside this column are at least a first and a second bed of granular solids respectively referenced 2 and 10, separated by a distributor according to the invention or DME comprising the following elements:
means for collecting a main fluid A1 circulating in the column through by
example the first bed of granular solids 2 comprising, for example, a collection grid
3 and a collection space 4,
a mixing chamber 7 which has one or more orifices 14 for introducing the fluid
main circulating in the column and at least one outlet 17 preferably
calibrated,
two injection and / or withdrawal circuits of a first and a second secondary fluid
B1 and B2, respectively comprising for example a conduit 12, 13 opening into a
injection and / or withdrawal chamber 5, 6 arranged, for example, near the chamber
mixing and communicating with the latter through one or more openings 15, 16
located on a common wall (5a, 5b) to the injection and / or withdrawal chambers and to the
mixing chamber.

 The two injection and / or withdrawal circuits are independent and communicate with the outside towards sources of separate secondary fluids or also separate recovery chambers also, not shown in the figure.

 The openings 15, 16 thus allow withdrawal and / or injection to the mixing chamber and / or from the mixing chamber.

 The size and distribution of the orifices 14 for introducing the main fluid A1, the orifices 17 for leaving the mixing chamber, as well as orifices 15 and 16 are preferably chosen to obtain a pressure drop or a loss of pressure and speed sufficient to generate turbulence in the mixing chamber 7. In this way, a strong back-mixing and better efficiency of the mixing of the main fluids A1, and secondary fluids B1, B2 are obtained. Such an arrangement also makes it possible to isolate the mixing chamber 7 of the collection and redistribution spaces, and to minimize the direct passage of current of secondary fluids to the collection and redistribution spaces.

 The inlet orifices 14 of the mixing chamber 7 are, for example, series of holes or slots, preferably, regularly spaced to achieve as uniform a collection as possible of the main fluid A1 towards the mixing chamber 7.

 The size and the geometry of these orifices are chosen so that the fluid at the inlet of the mixing chamber has a favorable speed to create inside turbulences and at the same time to generate a pressure drop enabling these turbulences to be confined inside the mixing chamber.

 Thus, the spacing between the inlet orifices 14 of the fluid A1 is, for example, between 30 and 150 mm and preferably between 50 and 100 mm. The speed of the fluid through the orifices obtained with such a spacing varies for example between 1 and 5 ms, preferably between 2 and 3 ms. The pressure drop thus generated at the outlet of the orifices is between 10 and 100 g / cm2 and preferably between 30 and 60 g / cm2.

 The outlet channels 17 for a fluid from the mixing chamber are for example formed by a series of holes or slots, preferably, regularly spaced so as to redistribute the fluid as uniformly as possible towards the space of redistribution 8. This fluid results from the mixture of at least one main fluid with at least one secondary fluid or else a remixing fluid.

 The size of the holes or slots 17 is chosen, for example to generate a certain pressure drop making it possible to confine the turbulence of the mixture inside the mixing chamber 7, for example a pressure drop of between 10 and 100 g / cm2 and preferably between 30 and 60 g / cm2. This pressure drop value corresponds in particular to a spacing of the holes or slots from 30 to 150 mm and preferably from 50 to 100 mm and to a speed value for the fluid leaving the mixing chamber of between 1 and 5 m / s, preferably between 2 and 3 m / s.

 In this way, the collection and the good distribution of the fluid coming from the mixing chamber and passing through the redistribution space 8 and then through the redistribution grid are optimized.

 The orifices 15, 16 for introducing or withdrawing the secondary fluids B1 and B2 are, for example formed by a series of holes, preferably, regularly spaced to inject and / or withdraw the secondary fluid B1, B2 in the most uniform manner possible to or from the mixing chamber 7. These orifices are, for example, dimensioned so that the linear speed of a secondary fluid entering the mixing chamber is large enough to promote the creation of turbulence inside this chamber and to obtain a significant pressure drop.

 The speed of the fluid through the outlet orifices 15, 16 is, for example, between 1 and 15 m / s, preferably between 5 and 10 m / s. The spacing between the holes is chosen, for example between 30 and 150 mm and preferably between 50 and 100 mm. The corresponding pressure drop varies between 100 and 2000 g / cm2 and preferably between 200 and 1000 g / cm2.

 As shown in FIGS. 2 and 3, the orifices 15 and 16 are arranged along the walls common to the injection and / or withdrawal chambers and to the mixing chamber so that the fluid passing through strikes a wall full of the mixing chamber located opposite the wall comprising the orifices. They are, for example, offset from each other to avoid the passage of a secondary fluid to a chamber which is not dedicated to it.

 The efficiency of the mixing in the chamber can also be obtained by choosing the geometry and the dimensions of the injection and / or withdrawal chambers to ensure a substantially identical flow of fluids over all the outlet orifices. For example, the ratio of the developed length of the chambers to their average or equivalent width is for example less than 30, preferably less than 20, and preferably less than 10.

 Advantageously, the width of the mixing chamber is chosen for example as a function of the value of the speed of one of the secondary fluids emerging through one of the orifices 15, 16 in the mixing chamber so that the secondary fluid meets the wall of the mixing chamber located opposite the wall from which this fluid comes.

 FIG. 3 thus shows two injection and / or withdrawal chambers 5, 6 having an elongated rectangular shape joined on either side of a mixing chamber 7 having a substantially identical shape. The mechanical assembly thus formed is in the form of a box, for example of substantially flat shape.

 This box separates, for example, entirely and practically over the entire section of the column, the collection space 4, and the redistribution space 8.

 According to another embodiment, the DME is for example in the form of a substantially flat "pancake", for example arranged horizontally when the axis of the column is vertical, preferably having a reduced thickness, the peripheral shape being able to be circular.

 The assembly thus obtained is advantageously in the form of a box which performs both collection, distribution and / or mixing and / or withdrawal of fluids functions at the same time as a support function.

The method implemented using this device comprises, for example, the following steps given solely by way of illustration, in no way limiting
For example, a main fluid A1 is introduced through the upper opening of the column, for example D. This fluid circulates through the first upper bed 2 before being collected as uniformly as possible at the level of the collection grid. 3 and the collection space 4. It enters the mixing chamber 7 through the calibrated orifices 14, arranged, for example, over substantially the entire length of the upper wall of the mixing chamber. An uniform main fluid is thus introduced into this chamber, while generating turbulence which is beneficial to the efficiency of the mixture inside.

The injection of the secondary fluids B1 and B2 into the separate injection and / or withdrawal chambers is carried out, for example, sequentially but according to a substantially identical diagram as follows: e the secondary fluid B1 (respectively B2) is brought in and introduced into chamber 5 (6) by the
tubing 12 (13), for injecting into the mixing chamber 7 through the calibrated orifices 15 (16),
distributed for example uniformly over the entire length of the chamber to obtain a
uniform injection and at a high injection speed favorable to the effectiveness of the mixture with the
main fluid Al by the creation of strong turbulence in a confined space, formed by the
mixing chamber 7 and the orifices 14, 17.

 Conversely, these secondary fluids B1 and B2 can be drawn off through the same device. The sampling of the fluids obtained is thus uniform in the mixing chamber 7 thanks to the calibrated orifices 15, 16, as well as their collection in the chamber 5, 6. They are then withdrawn by the pipes 12, 13.

 Figures 4, 5 and 6 show schematically in several sections, one of the possible possibilities for distributing the injection and / or withdrawal lines of the secondary fluids B1 and B2 for a column comprising two injection and / or withdrawal chambers.

 The pipe 20 for injecting and / or withdrawing a first fluid B1 is composed of a first part 20a which crosses the column 1 radially, this first part being extended by a second part 20b which crosses the grid and the space collection (3, 4) for example in a direction substantially parallel to the longitudinal axis of the column to open at the upper wall of the injection and / or withdrawal chamber 5.

 Line 21, which for example has a substantially similar geometry, has a first part 21a and a second part 21b, and is brought to the level of the bottom wall of the second injection and / or withdrawal chamber 6 through the grid. 8 and the redistribution space.

 In the embodiments described in these three figures, the orifices 15, 16 are offset to prevent the passage of the fluid B1 in the chamber 6 and the fluid B2 in the chamber 5.

 FIG. 7 shows an example of a device comprising three injection and / or withdrawal chambers of three secondary fluids respectively B1, B2, B3.

The injection and / or withdrawal chamber 30 sees the passage for example of a first fluid
B1, and is arranged for example above the injection and / or withdrawal chamber 31 which sees the passage of a second secondary fluid B2. Each of these chambers 30, 31 communicate with the mixing chamber 7 by means of one or more orifices 32, 33 having injection axes preferably opening onto a solid wall of the mixing chamber 7, situated for example opposite the walls comprising the orifices 32, 33.

 These two chambers are, for example, arranged on the same side of the mixing chamber, along a wall having a direction substantially parallel to the vertical axis of the column.

 On the other side of this chamber, there is a third injection and / or withdrawal chamber 34 which has for example a height substantially identical to the added height of the two chambers 30 and 31. It communicates with the mixing chamber 7 by one or more calibrated orifices 35 whose axis opens onto a solid wall of the mixing chamber.

 In this way the different secondary fluids B1, B2, B3 injected into the mixing chamber will "crash into a solid wall which allows these fluids to mix intimately within the mixing chamber 7 and more avoid the passage of secondary fluids having different natures in rooms which are not dedicated to them.

 The means for collecting and / or redistributing the mixture have characteristics substantially similar to those of the spaces described in the preceding figures.

 The same applies to the characteristics of the orifices 14 for introducing and leaving the main fluid in the mixing chamber, as well as the orifices for the passage of the various secondary fluids from the injection and / or withdrawal chambers of the chamber or to the mixing chamber.

 FIG. 8 shows the arrangement of four injection and / or withdrawal chambers 40, 42, 44 and 46, and the distribution of the various conduits for the fluids B1, B2, B3 and B4 relative to the column.

 In this case, the lines 41, 43 and 45, 47 respectively introduce and / or withdraw the four fluids B1, B2, B3 and B4.

 The pipes 41 and 43 may have shapes and paths similar to those described in FIG. 4 to reach the two injection and / or withdrawal chambers 40 and 42 by crossing the upper wall of each of these chambers, the pipe 43 crossing the chamber 40 along an axis substantially parallel to the axis of the column and over its entire height when the chamber 40 occupies the entire section of the column or in the case where this chamber is positioned above the chamber 42 and has a section greater than the section of the chamber 40.

 The pipe 45 passes through one of the longitudinal walls of the column 1 radially to join along a route having a geometry substantially identical to that of the pipe 43 the upper wall of the injection and / or withdrawal chamber 44, then that in this exemplary embodiment, the pipe 47 adopts a similar route to reach the injection and / or withdrawal chamber 46 at its lower wall.

It is understood that without departing from the scope of the invention, the routes and geometries of the various pipes can be adapted as a function of the following parameters:
the geometry of the column, the number and geometry of the different chambers, the conditions of access to the column.

 FIG. 9 shows an example of DME comprising five independent circuits for injecting and / or withdrawing secondary fluids.

 This exemplary embodiment may be particularly advantageous, for example for supplying an auxiliary fluid serving, for example, for rinsing or ultimate purification operations before drawing off a product of high purity. In this example, the axes of the orifices always respect an orientation and distribution criterion so that the fluid passing through strikes a solid part of a wall of the chamber.

 In FIG. 10, an embodiment of DME has been described in which the mixing chamber 60 is located on one side of the DME and thus has a common wall with one of the longitudinal walls of the column 1. It is provided on the side of the collection space 4 of at least one orifice 61 for letting the main fluid A1 pass, this orifice having for example characteristics substantially similar to those of orifices 14 (FIG. 1) and of one or more calibrated orifices 62 allowing passage of the mixture, these orifices having, for example, characteristics substantially identical to the characteristics of the orifices 17 (FIG. 1).

The two chambers 63, 64 for injecting and / or withdrawing the two secondary fluids B1,
B2 are positioned on the same side of this mixing chamber 60, for example, along a wall whose direction is substantially parallel to the axis of the column, the chamber 63 being, for example, placed above the chamber 64. The injection and / or withdrawal chambers communicate with the outside via conduits such as conduits 12, 13 not shown for the sake of clarity and communicate with the mixing chamber 60 through one or more orifices 65, 66 determined by criteria similar to ports 15 and 16 (Figure 1), for example.

In this figure, the collection means 3, 4 as well as the redistribution means 8, 9 make it possible to reduce the differences in travel time for the fluid lines of the main fluid flowing from the first upper bed to the second bed of granular solids located downstream of
DME and fluid from the mixing chamber.

 In the case of a column with large sections, it is advantageous to have several DMEs next to each other and / or one above the other, rather than a single DME which would have a size substantially identical to the size obtained by the positioning of all the EMRs in the column but which would lead to more significant difficulties in implementation. Due to the independence of the injection and / or withdrawal chambers of the secondary fluids, such an arrangement can lead to having a significant number of tubes or pipes, passing through the wall or walls of the column and being able to clutter and increase the complexity of the column. In this case, it turns out to be advantageous to adopt a configuration for the inlet pipes for these secondary fluids, according to a diagram, for example described in FIGS. 11, 12, 13 and 14.

 In these figures, the various tubes Ci making it possible to inject and / or withdraw a secondary fluid of a specified nature, are brought together inside the column at the level of a tube or pipe C. Only the main pipe C passes through at one or more places the walls of the column.

 For example in FIGS. 11 and 12, the conduits C and C 'making it possible respectively to inject and / or withdraw the fluids B1 and B2, have ramifications Ci and C'i which allow the passage of the secondary fluids towards the chambers d injection and / or withdrawal. The term “appropriate chamber” is intended to mean the chamber which is intended to receive, both in the withdrawal steps and in the steps of injecting secondary fluids, one and only one fluid, or possibly fluids compatible with each other.

 In FIG. 12, the column shows the presence of three DME D1, D2, D3 positioned one next to the other according to the section of the column and each having characteristics substantially identical to those of the DME described in FIG. 1. They comprise each at least one mixing chamber M and two injection and / or withdrawal chambers 11, 12 located on either side of the mixing chamber M.

 The main pipes C and C 'are arranged, for example, above the DME as shown in Figure 11, horizontally and in a radial direction, for example and the ramifications Ci, C'i leave the main pipes C and C' in a substantially perpendicular direction for example to join the injection chambers and / or withdrawal type II, 12 respectively. It is understood that without departing from the scope of the invention the horizontal or vertical arrangement of these pipes and their ramifications, as well as their geometry depends on the mode and the position of the column, for example, the latter being able to be used horizontally or vertically.

 In the same way, it is possible to imagine superimposing the main injection pipes C and C ′ by adapting the shape of the branches coming from the main pipe positioned above the other, or any other variant embodiment.

 FIGS. 13 and 14 describe a diagram for dispensing secondary fluids while minimizing the difference in travel times between the point of entry of the fluid in the distribution circuit to its point of injection into the injection chamber and / or racking.

 For a column comprising, as in FIG. 12, three DMEs arranged one beside the other, the external conduit 70 dedicated to the fluid B1 is extended inside the column 1 by a part of conduit 71 for example of circular shape on at at least part of its length and adopting the shape of the periphery of the DME, its length being adapted to reach and distribute the fluid B1 in all the injection and / or withdrawal chambers II dedicated to the fluid B1 by means of ramifications for example pieces of pipe 71 i.

It is the same when we consider the fluid injection and / or withdrawal line
B2 which is distributed via the pipe 72 extended by the piece of circular pipe 73 itself branched by pieces of pipe 73i opening into the different injection and / or withdrawal chambers.

 In FIGS. 13 and 14, the two injection and / or withdrawal conduits 70, 72 are shown on opposite parts of the periphery of the column.

 This arrangement offers in particular the advantage of considerably simplifying the arrangement of the internal conduits for connection to the EMR, while leaving the maximum space for the sieve beds or granular solids situated on either side of the EMR and while disturbing as much as possible the circulation of the main fluid A1 through these beds.

 The various circular main pipes arranged inside the column may have a length corresponding to a part or substantially be equal to the circumference of this column. They can also be arranged one above the other.

 The number of common transverse pipes, straight or not, is chosen as a function, for example, of the number of DMEs positioned inside the column and of the number of secondary fluids which it is desired to be independent.

 Due to the independence of the injection and / or withdrawal circuits for the secondary fluids, the arrangement of the injection and / or withdrawal lines common to the branches can be of any shape without any symmetry of shape or residence time.

 When stopping the operations of injection and / or withdrawal of secondary fluids, there may be a weeping phenomenon resulting from a dynamic effect of the circulation of the main fluid A1 in front of the orifices. This phenomenon occurs in particular at the orifices calibrated in relation to the circuit of the secondary fluid concemed by this stop.

 For example, when the circulation of fluid in the chamber 5 is interrupted, the latter is completely filled, for example with secondary fluid B1.

 For its part, the main fluid A1 continues to circulate at high speed in the mixing chamber 7 and in particular passes in front of the calibrated orifices communicating the mixing chamber and the injection and / or withdrawal chamber. Due to the existence of turbulence of the fluid A1 in the mixing chamber, there may be a phenomenon of weeping, that is to say that a very small part of the main fluid will enter the injection chamber and / or withdrawal via the calibrated orifices, and conversely a very small part of the secondary fluid present in the injection and / or withdrawal chamber, will escape from this chamber towards the mixing chamber.

When the main and secondary fluids have different natures, this results in a possibility of reciprocal contamination, even when there is no secondary fluid flow.
B1.

 To limit or even eliminate this risk of reciprocal contamination, several devices or arrangements can be used.

 A first way of proceeding consists in minimizing the size of the calibrated orifices situated between the mixing chamber and the injection and / or withdrawal chambers, for example by choosing them preferably less than approximately 10 mm, preferably 7 mm, and if possible preferably less than 5 mm so as to minimize the importance of this weeping phenomenon.

 For example, by avoiding placing the injection and / or withdrawal orifices of secondary fluids facing the flow of the main fluid in the mixing chamber (axis of the orifices parallel to the direction of the main fluid), or by avoiding to give the mixing chamber a base which can create a nozzle or venturi effect with these orifices.

 A particularly advantageous arrangement, described in FIGS. 15 and 16, consists in associating with an injection and / or withdrawal chamber 5, 6, an injection and / or withdrawal prechamber 5A, 6A positioned between the mixing chamber 7 and the injection and / or withdrawal chamber 5, 6.

 Each of the injection and / or withdrawal pre-chambers 5A, 6A comprises one or more calibrated orifices 15A, 16A substantially identical to the calibrated orifices previously described and allowing the passage of fluids between an injection and / or withdrawal chamber and a pre-chamber , in addition to the orifices 15, 16 which allow the circulation of fluids from the mixing chamber to the pre-chambers. The orifices 15, 16, 15A 16A are for example arranged with respect to each other along offset axes to avoid the problems of encounter between secondary fluids having different natures, as was mentioned above.

Such an arrangement is particularly interesting because it has the following advantages in particular:
during the injection of a secondary fluid B1, for example, the calibrated orifices of the prechamber
allow a better equalization of the pressure prevailing inside the
prechamber and therefore to obtain a better distribution of the secondary fluid B1 through the
second series of calibrated orifices 15, 16 allowing the passage of the secondary fluid of a
prechamber to the mixing chamber,
the reduced volume of the prechamber provided with calibrated orifices 15, 15A, 16, 16A respectively
constitutes a confined space which limits the phenomena of weeping and contamination
reciprocal of fluids between them, essentially inside this prechamber when a
the secondary fluid circulation is stopped. Indeed, the wall common to the
mixture and in the prechamber, provided with calibrated orifices acts as an obstacle, which prevents
the turbulence created by the main fluid to propagate in the injection chamber and / or
dedicated to a secondary fluid.

 For this reason, the volume of this prechamber is preferably minimized. The width between walls is for example between 10 and 100 mm, and preferably is between 15 and 50 mm and more preferably chosen between 20 and 30 mm.

the mixing prechamber can also advantageously be used to produce
rinsing operations by injection of secondary fluid, or withdrawal of main fluid.

 For example, if the main fluid B1 is a clean product and there are risks of weeping phenomenon, that is to say risks of contamination of the volume contained in the prechamber by injecting an equal volume of fluid B1 or greater than the volume of the prechamber, the contaminated volume is pushed into the mixing chamber and thus clean fluid is obtained in the prechamber.

 Conversely, by withdrawing a reduced volume of a secondary fluid B2, for example by an amount at least equal to the volume of the prechamber, the prechamber is rinsed with the main fluid A1.

 FIG. 17 shows an arrangement of four injection and / or extraction chambers and their associated pre-chambers, arranged on either side of the column.

 Figures 18 and 19 schematically show two other embodiments of DME for which several injection and / or withdrawal chambers are associated with a single prechamber.

 In this case, each of the injection and / or withdrawal chambers is always "dedicated" to a single fluid but the associated prechamber can see different fluids.

These embodiments have the following advantages in particular:
the risks of crying phenomenon are minimized compared to the fixtures
comprising several pre-chambers since the number of calibrated orifices has been minimized,
clean secondary fluid is used to rinse the common prechamber,
conversely, when a volume of a secondary fluid is withdrawn greater than or equal to the
volume of the common prechamber, this stage is rinsed in a single step
common prechamber by the main fluid, which can advantageously be achieved when
the main fluid becomes clean.

 Advantageously, the DME according to the invention comprises collection means and / or redistribution means having a shape adapted to minimize the differences in travel time between the lines of fluid circulating in the beds of granular solids. Alternative embodiments of devices are described by way of nonlimiting examples in FIGS. 20, 21, 22, 23.

 For example, to homogenize the travel times of the lines of the main fluid flowing in the first upper bed 2 disposed upstream of the DME, collection space describes that FIG. 20 has a shape different from that of FIG. 1.

The collection space 4 (Figure 1) takes a delimited form:
by the walls 4a and 4b formed, for example, in part by the upper wall of the
mix 7
the upper walls of the injection and / or withdrawal chamber 5, 6, these walls 4a and 4b
being separated by opening 14, by grid 3, and
by the outer walls of the column.

 The main fluid circulates in the upper granular solid bed 2 in the form, for example, of a fluid piston, passes through the collection grid 3 then travels through the collection space 4 while flowing over the walls 4a and 4b. before entering the orifice 14 into the mixing chamber 7. The shape of the walls 4a and 4b is adapted so that the travel time of the lines of fluid Fi of the main fluid taken between its point of introduction at a level of the column until it enters the mixing chamber for the opening 14, which is substantially identical for all the fluid lines or for all the particles of the fluid through the bed and the collection space, whatever their radial position d introduction into the bed. The mixing chamber 7 is for example disposed substantially in the center of the column, and opening 14 located substantially along its axis A. The two walls of the collection space 4a and 4b have a slope which is defined to obtain the desired result.

 To optimize the shape of the collection space in order to obtain as perfect uniformity as possible, the propagation times of the different fluid lines, it is also possible to take into account the nature of the granular solids making up the beds, which may have an influence on the speed of propagation of the lines of fluids, because of the possible interactions of the fluid with the particles forming the bed of granular solids.

In fact, the fluid Fb collected at the edge of the DME and therefore towards the external walls of the column travels under the greatest length of the collection space before reaching the reopening of the mixing chamber, this increase in the distance compared to the central fluid
Fc is compensated for by the, for example inclined, shape of the wall 4a, the inclination angle of which is calculated as a function, for example, of the flow collected passing through each point of the collection space.

 The secondary fluid passes from the injection and / or withdrawal chamber to, or from the mixing chamber through the orifices 15 so as to mix with the main fluid. The mixture A2 thus formed is then discharged through the calibrated orifice 17 and redistributed by collection means, comprising for example a collection space 8 and a redistribution grid 9, towards the second bed of granular solids 10.

 The advantageous shape of the collection space by minimizing the differences in travel time between the different fluid lines avoids effects of streaks for the front of propagation of the main fluid. This drag effect or delay of one fluid line with respect to another is particularly detrimental to the quality of the chromatographic separation obtained through the bed of granular solids and is equivalent to a phenomenon of back mixing.

 The collection space has for example a conical shape, but can also take any form suitable for homogenizing the travel times of the lines of the fluid from its level N of injection into the column until the moment when it enters the mixing chamber.

FIG. 21 describes another embodiment where the shapes of the grid 3 and of the collection space 4 are combined together to obtain a substantially identical travel time for all the lines of fluid Fi whatever their position of travel in the column. For example, the length of the first bed traversed by the fluid lines Fi and placed upstream of the
DME so as to obtain a journey time or a cumulative journey time taking into account the granular bed and the collection space when it exists, substantially equal for all the particles of the main fluid.

 In FIG. 21, the grid 3 has for example a shape of a conical section, or in a bowl, or else it has, over at least part of its length, shapes which can be assimilated to inclined planes or any other shape capable of lengthening the length. of the bed in its central part to adapt the path length of the fluid lines according to the place where they circulate inside the column. In this way, an additional length of path Li is associated with each of the fluid lines Fi, for example, in this embodiment, the additional length Li of the bed decreases from the center of the column towards its edges.

In addition, in order to reduce the residence times of the main fluid in the collection space, the height h of this space and, preferably chosen to decrease from the center of the
DME towards the edges of the DME, which reduces dead volumes and journey times.

 The height h is for example chosen between 5 and 50 mm and preferably between 5 and 30 mm, for a space having a conical shape or in a bowl or having inclined walls.

 In some cases, the grid shape may be sufficient on its own.

 An almost perfect correction is thus obtained for the travel times of the different particles or lines of fluid flowing through the upper bed 2 before they enter the mixing chamber.

 In all the embodiments mentioned above, the collection space can be of substantially constant height h.

 FIGS. 22 and 23 schematize examples of arrangement of the collection space, combining means for separating the lines of fluids into several sub-flows with specific shapes of the wall (s) of the collection space 4.

 For example, the arrangement in FIG. 22 consists in inserting into the collecting space 4 a pbque 81 provided with two orifices 82 and 83, the plate being arranged in a manner substantially central to the DME and the orifices 82 and 83 located substantially equal to distance from the axis of the column which corresponds to the axis of the DME.

 In this way, a first collection of the lines of the main fluid is carried out which has the function of reducing the differences in travel time. Indeed, the lines of fluid Fb circulating towards the edge of the DME and the lines of fluid Fc circulating towards the central axis of the DME flow tangentially on the plate 81 from the center of the column or one of its walls by traversing a distance which is substantially identical but reduced by half, before passing through the orifices 82 or 83 and leading to a collection subspace 4 'delimited by the plate 81 and the walls 4'a and 4'b formed in part at less through the upper walls of the mixing chamber 7 and those of the injection and / or withdrawal chambers 5, 6, before passing into the mixing chamber 7 through the orifice 14. The orifices 82 and 83 are in this exemplary embodiment positioned substantially at 1/4 and 3/4 of the plate taken according to the width of the DME.

 The combination of the plate 81 and the collection by the two openings 82, 83 makes it possible to substantially minimize by half the differences in travel time between the fluid lines compared to a collection not equipped with this device.

 Another way of proceeding described in FIG. 23 consists in positioning at the level of the collection space 4, a plate comprising four inclined portions or surfaces 91a, 91b, 91c and 91d. The inclined surfaces 91a and 91b form a first collection space 92 for example conical or in a bowl having a passage opening 93 and the inclined surfaces 91c and 91d form a second collection space 92 ', for example having a passage opening 94 The openings 93 and 94 communicate with a space 4 'delimited by the walls 4'a and 4'b extending the inclined surfaces 91a and 91d.

 The main fluid lines circulate along the inclined surfaces whose inclination angle is chosen to homogenize at least in a first step the travel times of the different fluid lines before their passage through the orifices 93 and 94, the step final minimization being carried out thanks to the shape of the walls 4'a and 4'b.

 According to an advantageous embodiment of the device according to the invention, the DME also includes a space 8 making it possible to redistribute the mixture coming from the mixing chamber 7 by reopening 17. This redistribution space has in particular the function of redistributing the mixture so that that all the fluid lines constituting it or the particles reach the bed 10 located downstream of the DME at about the same time. The travel time from the point corresponding to the opening 17 to the collection grid 9 is substantially identical for all the fluid lines.

 This redistribution space includes, for example, characteristics substantially identical to those described in Figures 20, 21, 22 and 23 for the collection space.

 The redistribution space is, for example, identical to the collection space, designed to minimize dead volumes and turbulence. It has for example a height varying between 5 and 50 mm, preferably between 5 and 30 mm and preferably between 15 and 20 mm and can have any shape, for example rectangular or conical.

 Its height can be substantially constant or it is chosen to decrease starting from the center of the DME and going towards its edges, which makes it possible to minimize the dead volumes and the journey times.

It is understood that in the case of columns having large sections, the distribution and the shape of the DME can be chosen according to one of the modes described in the application.
WO-95/03867.

 The mixing chambers can take substantially elongated shapes, generally rectilinear, curved or broken on at least one of their parts.

 As far as the shape of the mixing chambers is concerned, they are, in all the embodiments described above, arranged substantially over the entire thickness of DME or in general over its entire thickness. Their shape is chosen to promote turbulence between the fluid or fluids contained in this chamber and therefore optimize the mixture.

 Turbulence promoters, for example the presence of baffles or lining advantageously promotes this mixture.

With regard to the positioning of the orifices at the level of the mixing chamber, the orifices for introducing the main fluid into the chamber and the outlet orifices are preferably arranged in an offset manner to optimize the transverse dispersion of the main fluid
A1 and secondary fluids B1, B2, ... mixed together in the mixing chamber.

 Preferably, there are the orifices for introducing the main fluid, for outlet as well as the injection and / or withdrawal orifices connecting the different chambers are preferably regularly arranged with the same spacing or not between the orifices.

 More preferably, the arrangement of the injection and / or withdrawal orifices relative to the orifices for introducing the main fluid so that a stream of fluid passing through an injection and / or withdrawal orifice mixes with the fluid main inside the mixing chamber, the latter being provided with several outlet orifices which are arranged alternately or staggered with respect to the introduction orifices so that the mixture is redistributed at least in two streams.

 According to one embodiment of the invention, a device such as a jet breaker is arranged at the level of the redistribution space, for example in the axis of the outlet orifices so as to avoid the fluid coming from the mixing chamber to directly strike the second bed of granular solids disposed downstream of the DME.

 This procedure leads to a better radial distribution of the fluid in the redistribution space.

 A similar result is obtained by using a mixing chamber whose dimensions along the axis of the column are elongated, these longitudinal walls exceeding the height of the injection and / or withdrawal chambers and penetrating at least over a height of the space of redistribution. The mixing chamber comprises, on each of the walls penetrating into the redistribution space, at least one opening for passage of the mixture towards the redistribution space.

The chamber can be extended by walls substantially parallel to the axis of the column or by walls having an angle of inclination relative to the axis of the column.

 In order to avoid the pronounced turbulence phenomena in the vicinity of the first bed of granular solids, and to promote the collection of the main fluid in the collection space, similar use is made, for example, for the introduction orifices by including jet breaker still side holes on the mixing chamber extended under the collecting grid.

Claims (14)

 1 - Device for distributing, mixing, injecting and / or withdrawing several fluids, one of the fluids being a main fluid A1, and at least a first secondary fluid B1 and a second secondary fluid B2, said device comprising means for collection (3, 4) of said main fluid A, said collection means being in connection with at least one mixing chamber (7), at least one first circuit (12, 5) for injection and / or withdrawal of a first secondary fluid B1, and at least one second circuit (13, 6) for injection and / or withdrawal of a second secondary fluid B2, said injection and / or withdrawal circuits being in communication with the mixing chamber (7) using one or more openings (15, 16) allowing said secondary fluids (B1, B2) to pass through said mixing chamber (7), said mixing chamber (7) comprising at least an inlet orifice (14) and an outlet orifice (17), characterized in that said circ injection and / or extraction uits are distinct and arranged near said mixing chamber along at least one of its walls which has a direction substantially parallel to the axis of the DME.  2 - Device according to claim 1 characterized in that said separate injection and / or withdrawal circuits are arranged one above the other and on the same side of said mixing chamber.  3 - Device according to claim 1 characterized in that said injection and / or withdrawal circuits are arranged along one or more of the walls of the mixing chamber.  4 - Device according to one of claims 1 to 3 characterized in that the number of injection and / or withdrawal circuits is at least greater than 4.  5 - Device according to one of claims 1 to 4 characterized in that at least one of said injection and / or withdrawal circuits is associated with at least one injection and / or withdrawal pre-circuit.  6 - Device according to one of claims 1 to 4 characterized in that at least one of said injection and / or withdrawal circuits is associated with an injection and / or withdrawal pre-circuit.  7 - Device according to one of the preceding claims characterized in that said injection and / or withdrawal circuits and said injection and / or withdrawal pre-circuits communicate with said mixing chamber or between them by one or more orifices arranged according to the walls of the different chambers or of the different circuits so that the axes of the orifices are offset from one another.  8 - Device according to one of the preceding claims characterized in that it comprises collection means and / or redistribution means whose shape is adapted to minimize the differences in the travel times of the fluid lines before said mixing chamber and / or after said mixing chamber.  9 - Device according to claim 8 characterized in that said collection means comprises a collection grid (3) extending substantially over the entire section of the DME and / or a collection space (4), at least the one of said elements having a shape adapted to minimize the differences between the travel times of the different flow lines of the main fluid before their entry into the mixing chamber (7), in that said redistribution means comprises at least one grid of redistribution (9) extending substantially over the entire section of the DME, and in that the redistribution means include at least one redistribution grid and / or a redistribution space (8), at least one of these elements having a shape adapted to minimize the differences between the travel times of the different lines flow of the main fluid after leaving the mixing chamber.  10 - Column allowing the separation of a body from a fluid comprising at least several separable compounds, comprising at least a first and a second bed of granular solids separated by a DME, said DME comprising collection means (3, 4) of said body to be separated, said collection means being in relation with at least one mixing chamber (7), at least one first circuit (12, 5) for injecting and / or withdrawing a first secondary fluid B1 and at least one second circuit (13, 6) for injecting and / or withdrawing a second secondary fluid B2, said injection and / or withdrawal circuits being in communication with said mixing chamber (7) using one or more openings (15, 16) allowing the passage of said secondary fluids (B1, B2 ) in said mixing chamber, said mixing chamber (7) comprising at least one introduction orifice (14) and one outlet orifice (17), characterized in that in that said injection and / or racking are distinct and arranged near said mixing chamber along at least one of its walls which has a substantially parallel direction araxedu DME.  11 - Column according to claim 10 characterized in that it comprises at least four independent injection and / or withdrawal circuits arranged along at least one of the walls of said mixing chamber, said wall of the chamber having a substantially parallel direction to the column axis.  12 - Column according to claim 10 characterized in that it comprises collection means and / or redistribution means having a shape adapted to minimize the differences in travel time of the differences in fluid lines having passed through at least part of a bed of granular solids before their entry into the mixing chamber and / or homogenize the travel times of the lines of fluids coming from the mixing chamber until they enter the second bed arranged downstream of the DME.  13 - Column according to one of claims 10 to 12 characterized in that it includes several DME positioned according to one of the sections of said column and arranged one next to the other.  14 - Column according to claim 13 characterized in that the conduits for injecting one or more secondary fluids B1 at an injection and / or withdrawal chamber dedicated to this fluid are connected to the interior of said column at at least one main conduit passing through at least one of the walls of said column.