CH641373A5 - Process for centrifugal separation and apparatus for its use, both applicable to a mixture of phases in any states - Google Patents

Abstract

The apparatus comprises, arranged coaxially and driven in rotation in a stationary enclosure (1), a fan (2) generating a pressure reduction upstream, a rotary distributor (5) converting the pressure drop which results from the action of the fan (2) on the upstream pressure into a speed of rotation of the mixture which is added in the same direction to the speed of rotation of the distributor (5), and a rotor (4) comprising members (15) for guiding live streams, trapping members (16) which trap these dead sheets and collect heavy particles, and conducting members (18) for the latter. <IMAGE>

Description

** ATTENTION ** start of DESC field can contain end of CLMS **.

ment in correspondence with the chosen slope of the living veins in flow relative to the rotor.

19. Apparatus according to claim 18, characterized in that the trailing edges (22) of the vanes (21) are integral with a disc (13) coupled to the rotor (4) and limit the cutouts (15) of this disc in rear if we consider the rotation of said rotor.

20. Apparatus according to claim 5, characterized in that the action turbine (3) comprises a plurality of blades (39) oriented from the center to the periphery and whose concavity (40) opens upstream if the the flow of the mixture (E) is considered, the leading edge (41) of each blade being inclined substantially in correspondence with the chosen slope of the flowing streams relative to the rotor.

21. Apparatus according to claim 20, characterized in that the leading edges (41) of the vanes (39) are integral with the last downstream disc (13) of the rotor (4), if the flow of the mixture is considered. , and limit openings (15) of this disc forward, if we consider the rotation of said rotor.

22. Apparatus according to one of claims 4 to 21 characterized in that it comprises flat plates (13) and perpendicular to the axis of rotation.

23. Apparatus according to one of claims 4 to 21, characterized in that it comprises frustoconical plates (14) and converging downstream of the flow of the mixture.

The present invention relates to a centrifugal separation process for a mixture of phases of any state: gas in gas, liquid in gas, pulverulent solid in gas, liquid in liquid, pulverulent solid in liquid or other combinations of three phases between them. It also extends to an apparatus for implementing this method.

US Patent No. 3234716 describes a centrifugal separator apparatus comprising a rotor consisting of a stack of frustoconical plates having openings arranged opposite one another to form chimneys. The mixture to be treated is driven at the same angular speed as the rotor; it circulates radially, the light phase towards the center and the heavy phase towards the periphery. Furthermore, a transfer of mixture occurs between the plates through the chimneys, but the transfer circulation is axial and does not induce any force added to the centrifugal force.

French patent No. 1568746 also describes a centrifugal separator device comprising a stack of plates whose orifices are angularly offset from one plate to the next so that the phases travel radially between two plates and in a zigzag direction in an axial direction. from one plate to the following. A force field is added perpendicular to the centrifugal field, but is not superimposed on it to intensify the field due to the rotor alone; moreover, the paths of the mixture are, in superposition, tangential and axial in zigzag and not helical, inducing the mixture animated with the rotor at an angular speed greater than that of the rotor.

The present invention aims to generate within the mixture an extremely intense centrifugal field and much higher than that to which a rotating crew participating in the treatment is subjected. Consequently, the manufacture of this rotating assembly is thereby simplified and can implement economic techniques which are unusual in the field of centrifugation, for example the molding of rotating parts in plastic material.

Furthermore, due to the high intensity of the centrifugal field, the separation of the phases can be improved even when the specific masses of these are very low and very close to each other.

Concomitantly, the aerodynamic phenomena can be such that a large part of the kinetic energy of centrifugation can be recovered, with a view to reducing the overall energy consumption and thus improving the economic efficiency of the treatment.

These same phenomena can generate, by thermodynamic effect, cooling within the moving mass, which can be beneficial in particular for condensing a vapor phase.

According to the invention, the centrifugal separation process is characterized in that the mixture is rotated at an angular speed greater than that of a rotating crew that this mixture must pass through, in that the mixture is divided into a plurality of veins flowing along helical trajectories through the rotating crew and at a tangential speed greater than that of the latter, in that these living veins are separated by dead intermediate helicdidal fluid blades held captive by this rotating crew, in that the heavy phase or phases ejected from the living veins by the centrifugal field of the latter are trapped by the dead blades, in that the heavy phase or phases trapped in the dead blades and subjected to the centrifugal field which prevails in the latter , being less than that established in the veins, move towards the periphery, and in that the heavy phase or phases moving into the dead laminae are guided by r the mobile crew.

Alternatively, the mixture can be subjected, for its upstream rotation, on the one hand, to the positive action of the rotating assembly and, on the other hand, to a downstream axial suction or to an upstream axial discharge through this equipment, the resulting upstream pressure drop being transformed into a helical speed whose tangential component is superimposed on the tangential speed of said rotating equipment and whose axial component generates the flow rate.

In addition, the helical flow of the mixture can be straightened downstream to be transformed into an absolute axial flow and the kinetic energy of rotation of the treated mixture is recovered to drive the rotating crew in rotation and thus reduce the power consumed by it. -this.

According to the invention, the apparatus implementing the method is characterized in that it comprises, arranged coaxially and driven in rotation in a fixed enclosure, a first device consisting of a fan, a compressor or pump, intended to generate a upstream depression, a second device consisting of a rotary distributor transforming the pressure drop which results from the action of the first device on the upstream pressure into a speed of rotation of the mixture adding in the same direction to the positive speed of rotation of the distributor, and a third device located downstream of the second and consisting of a rotor comprising elements for guiding the living veins which direct and channel them over at least part of their path, trap elements which trap the fluid blades dead and capture the heavy phase (s) and which, while opposing the escape of the heavy phase (s) to the veins, participate in the progression of this o u of these heavy phases towards the periphery.

Subsidiarily, the apparatus may comprise, downstream of the third device or rotor if the flow of the mixture is considered, a fourth device consisting of an action turbine whose profile is adapted to this particular helical flow so that the latter becomes substantially axial, the blades also channeling the residual traces of heavy phase towards the periphery.

In addition, at least some of the four devices can be coupled together and connected to a common rotational drive device.

According to a particularly advantageous embodiment, the rotor comprises at least two coaxial plates of revolution, spaced from each other and delimiting openings which extend from the center towards the periphery, are separated for the same plate by parts solid and are, seen in plan, angularly offset from one plate to the next; the edges of the openings of the rotor rigorously define the envelopes of the multiple living helical veins and, concomitantly, those of the dead blades which separate them; the angular offset of the plates, the spacing thereof as well as the shape and dimensions of the openings are chosen to determine the relative slope of said veins and thus the separating power and the flow rate of the apparatus; prominent elements, such as edges or ribs, integral with the solid parts, can protrude exclusively in the dead blades, on the one hand, to trap the latter at the edge of the living veins and, on the other hand, to confine the heavy phase or phases which escape from the latter into said dead blades and guide the one or more towards the periphery.

In this preferred embodiment, the second device or rotary distributor comprises at least two coaxial plates of revolution, spaced apart from each other and delimiting openings which extend from the center to the periphery, are separated for the same plate by solid parts and are, seen in plan, angularly offset from one plate to the next; these openings of the distributor are each bordered by a single rim or blade projecting on the upstream face of the neighboring solid part, if we consider the flow of the mixture, and behind, if we consider the rotation of the plates or , in equivalence, on the downstream face and in front.

The characteristics and advantages of the invention moreover emerge from the detailed description which follows.

Embodiments of the object of the invention as well as particular embodiments are shown by way of non-limiting examples in the drawing: fig. 1 is a perspective partly broken away showing a first embodiment of the centrifugal apparatus according to the invention, fig. 2 is a partial perspective similar to FIG. 1 and illustrating a second embodiment of the apparatus, fig. 3 is a very schematic perspective showing for a first embodiment of the rotor the method of the invention, figs. 4 to 10 are sections taken concentrically to the axis of rotation and developed flat, showing the method of the invention for various embodiments of the rotor and sometimes of the rotary distributor, figs. 11 and 12 are views similar to FIGS. 4 to 10 above, relating to particular embodiments of the rotary distributor and the impeller, respectively, figs. 13 and 14 are partial plan views of a plate, illustrating several possible conformations of the openings.

As shown in fig. 1, the apparatus comprises a fixed enclosure 1 in which are arranged coaxially and rotated, from downstream to upstream, if we consider the direction indicated by arrow F of the flow of the mixture to be treated, a fan 2, an action turbine 3, a rotating assembly or rotor 4 and a rotary distributor 5.

In the example shown, these devices 2 to 5 are moved positively and in synchronism; therefore, they are wedged on the same shaft 6 which can be coupled, at one end or the other, to any rotational drive device, but appropriate to the speed of the apparatus. This is not a necessary measure, because it is perfectly possible to envisage making the fan 2 turn positively at a different but suitable speed; it is also possible to design a positive drive for one or two devices only (the rotor 4 and the distributor 5, for example) and a floating assembly to follow for the others (the action turbine 3, for example).

In addition, the axis of rotation is vertical in the drawing, but it can also be horizontal or inclined.

The enclosure 1 contains a target 7 which concentrically surrounds the rotating assembly 4 and possibly the distributor 5 to collect the heavy phase or phases which reach the periphery. In the example shown, the target 7 is laminated and consists of a stack of frustoconical rings 8 spaced apart from each other.

The fan 2 is intended to generate a drop in pressure upstream and a flow rate of the mixture to be treated downstream, in particular through the rotating assembly. In the example shown, the fan is of the centrifugal type; its rotary vane 9 is suitably wedged on the drive shaft 6 and is housed in a volute 10 reported and fixed on a convergent connection 1 1 of the body of the enclosure 1; the tangential tubing 12 of the volute makes it possible to evacuate the treated mixture free of heavy phase.

It is obvious that the fan can be of another type, axial in particular, and that it can be replaced by a compressor arranged upstream; likewise, if the mixture, instead of being gaseous, is liquid, a suction or pressure pump can be used.

The upstream pressure drop, which results from the downstream axial suction or from the upstream axial discharge, is transformed by the aforementioned rotary distributor 5 into a helical speed whose tangential component is superimposed on the tangential speed of the rotor and whose axial component generates the flow.

According to the embodiment shown in FIG. 1, the rotating assembly or rotor 4 is formed by a stack of circular flat plates 13 and, according to the embodiment illustrated in FIG. 2, this rotor is formed by a stack of frustoconical plates 14.

The means described in what follows with regard to the embodiment of FIG. 1, embodiment in which the generatrices of the plates 13 are straight and perpendicular to the axis of rotation, are obviously applicable to the embodiment of FIG. 2 and others, in which the generators may be curved and, if they are straight or curved, concurrent with or left with respect to the axis of rotation with any angle of incidence. In other words, the plates can be ruled surfaces, such as conics, or any balanced surfaces of revolution, which cannot constitute a major difficulty of execution as soon as the plates can be, due to the constraints. reduced they undergo, as the description will show, manufactured by molding, and even plastic.

In the example referring to FIGS. 1, 3 and 5, the plates 13 are spaced from each other at constant pitch p. Each plate 13 delimits openings 15 distributed in an equiangular manner, extending from the center towards the periphery and separated by solid parts 16. In the example shown, each solid part marks, by its raw front edge 17 and by its rear edge. 18, if we consider the direction of rotation T of the plates, the limits of the two neighboring openings; since said boundaries are radial, said openings and said solid parts have a trapezoidal shape.

It is essential to note that the plates 13 are angularly offset from one to the next or to the previous one by an angle ss (fig. 3), so that the openings are no longer located opposite each other. others, but gradually define helical envelopes with a privileged slope a with respect to the rotor (fig. 5). Inside such virtual envelopes flow vivid helical veins 19 of the mixture to be treated, if these are suitably speeded up by the rotary distributor 5. Outside these virtual envelopes stagnate or remain at a low rate. of renewal of the dead helical fluid blades 20 held captive by the rotating crew between the solid parts 16 of the plates.

In reality, the rotor 4 thus formed divides the mixture to be treated into a plurality of dead helical veins 20 interposed. The living veins, while crossing this rotor following said helical trajectories, flow at an absolute tangential speed much greater than that of the rotor, while the dead blades, being trapped therein, circulate substantially at its tangential speed.

Under these conditions, it is observed that, for a rotor rotating at the angular speed o, the absolute tangential speed of a particle located at a radial distance R is: 60R if this particle is in a dead blade, o) R + VT if this particle is in a living stream passing with respect to the rotor at the substantially constant relative tangential speed VT.

Therefore, the centrifugal force of such a particle is: FCH = 2R in a dead blade, and

in a living vein.

It is clear that the centrifugal force Fcv in the living veins 19 evolves in conical variation along the rays. It is minimal at a point where the relative tangential speed of the flow is equal to the absolute tangential speed of the rotor; at this point, the minimum centrifugal force is equal to 4 on2R, and consequently to four times the centrifugal field which prevails on the circumference of the same radius in the dead blades 20. The centrifugal force is very intense in the center, it decreases until at the point where it reaches its minimum, then it grows again to the periphery where it can reach extremely intense values.

This phenomenon, as well as the results presented below which result from it, are unpredictable and unexpected in the conventional framework of centrifugation. It is indeed the experimental facts based on the method and the apparatus of the invention which make it possible to ensure the veracity of the results obtained.

It is in fact verified that the heavy particles of the living veins 19 subjected to a very intense centrifugal force rush towards the periphery, slowing down and agglutinating before reaching the annular zone of minimum force and then, from this zone, accelerate. again in larger masses towards the periphery. But, during this centrifugal displacement, the heavy particles migrate, for various reasons explained below, towards the dead plates 20 in which they are caught and trapped; they are then supported by a centrifugal force, certainly weaker, but high enough to transport them inevitably to the periphery; during this transport, trap elements and conductive elements, defined below, oppose the escape of heavy particles towards the living veins and participate positively in their transport to the periphery where they rush into the rings frustoconical 8 of target 7 which definitively withdraws them from the mixture.

It is obvious that the angular offset ss of the plates 13 and the spacing p thereof (fig. 3), as well as the shape and dimensions of the openings 15 are chosen to precisely determine the slope relative to the living veins. 19 (i.e. their slope relative to the plates 13 when they rotate). The parameters in question therefore make it possible to adjust the resolving power and the flow rate of the device. In general, these parameters are constant for a given device, but it may be advantageous to vary them from upstream to downstream depending on the rate of operation of this device and that of the treatment to be obtained.

In any event, the choice of said parameters makes it possible, in relation to the speed of the apparatus and the composition of the mixture, to define the privileged helical path of the live veins 19 through the openings 15 of the rotor. Thus, each vein taking an opening n of the plate can continue its path by crossing the homologous opening n of the following plate, that is to say the one which is offset downstream-before the offset angle ss plates (fig. 3); but also, each vein can skip one or more openings, the following passage opening (n + 1), (n + 2), ... then being offset downstream-forward with respect to the reference opening n of an angle (13 + #), (13 + 2 "), ... y being the angular pitch of the openings on the same plate (fig. 3).

The rotating assembly or rotor 4 operates in the manner explained in the foregoing, due to the presence of the rotary distributor 5; in fact, it is recalled that this distributor, by transforming the upstream pressure drop into a helical speed of the mixture, directs living veins of the latter towards the selected envelopes of the perforations of the plates. Consequently, the relative speed of rotation of the veins due to this action is added in the same direction to the positive speed of rotation of the distributor which is that of the rotor.

According to the embodiment shown in FIGS. 1 and 11, the distributor 5 comprises a plate 13 with openings 15 and solid parts 16 offset in correspondence with those of the plates of the rotor 4. This particular distributor is an impeller consisting of a plurality of vanes 21, the concavity of which opens towards downstream of the flow of the mixture in the direction of arrow E. The trailing edge 22 of each blade coincides with the free edge 17 of the solid part 16 which delimits the perforation 15 into which the blade in question emerges; moreover, this trailing edge 22 is inclined along the slope relative to the living veins 19. Consequently, the blades are advantageously integral with at least some of the solid parts, in general with all, since they are preferably in number. The curvature of the concavity 23 and the conformation of the leading edge 24 are established as a function of the aero- or hydrodynamic characteristics of the mixture and of the operating speed.

The preceding description relates to the launching by the distributor 5 and to the helical routing through the openings 15 of the rotor 4, of the living veins 19. The following description now concerns the stabilization of the dead blades 20 in the helical spacers formed between the solid parts 16 of the rotor plates, the capture and trapping of heavy particles coming from the live veins in the dead blades, the positive guidance of the heavy particles trapped in the dead blades towards the periphery.

To achieve these combined results, several embodiments illustrated by FIGS. 4 to 10 can be used.

According to the simplified embodiment of FIG. 4, the plates 13 are smooth and very close to each other. Due to the fact that the mixture to be treated has a certain viscosity, that the solid parts 16 at least of the plates 13 have a surface state suitable for a certain adhesion of this mixture and that the flow E of said mixing is carried out at a sufficiently high speed to create a skin opposing the remixing of the content of the dead blades with the content of the living veins, while allowing the heavy particles of these to penetrate into said dead blades, these blades dead bodies are truly trapped between two solid 16 consecutive parts. The heavy particles trapped in these blades travel quite naturally through them under the effect of the centrifugal force of the rotor towards the periphery, but cannot manage to pass through them. reverse the skin of the neighboring living veins.

Such an embodiment (FIG. 4) is applicable to the separation of extremely fine particles which can go as far as molocular separation.

When the plates 13 are further apart from each other for all kinds of reasons, moreover, the desired results are obtained by providing prominent elements, such as edges, ribs or the like, made integral by any appropriate means with the solid parts 16 of the plates. It is essential to note that these prominent elements protrude only in the dead blades 20 and should not appear so faintly in the living veins, which they risk destroying or disturbing. Said protruding elements cooperate with the solid parts 16 to keep the dead blades 20 trapped in the rotor, to confine in these blades the heavy particles which escape from the living veins and to positively guide said particles towards the periphery.

Such prominent elements are illustrated in FIGS. 5 to 10.

According to a first embodiment of this type shown in FIG. 5 and already mentioned with reference to FIGS. 1 to 3, each solid part 16 of a rotor plate 13 comprises a single marginal rim 18 which projects on the upstream face of this solid part (if we consider the flow E of the neighboring live veins 19) and in rear (if we consider the rotation T of the plates).

According to a second embodiment equivalent to the first and emerging from FIG. 6, each solid part 16 comprises a single marginal rim 25 projecting on the downstream face (relative to the flow E of the live veins 19) and forward (relative to the direction of rotation T of the rotor).

According to a third embodiment combining the previous two and shown in FIG. 7, each solid part 16 has an upstream-rear flange 18 and a downstream-front flange 25 projecting.

Figs. 5 to 7 show that the flanges 18 and 25 can be perpendicular to the solid parts 16 of the plates. But it is clear that these can be replaced partially or entirely by inclined flanges 18a and / or 25a (FIG. 9). Ultimately, the solid parts 16 of the plates 13 may be bordered by inclined edges 18b and 25b (Fig. 10), the slope of which is equal to the slope of the veins with respect to the rotor.

According to the embodiment shown schematically in FIG. 8, each solid part 16 of the plates may include at least one intermediate rib 26 and / or 27 projecting on its upstream face and / or on its downstream face in the corresponding dead blade 20 and between the two neighboring openings.

The aforementioned edges and ribs, whether straight or inclined, can be combined with one another according to various arrangements, as long as no prominence exists in the living veins and the existing prominences hold the dead blades prisoner, then trap and channel heavy particles.

The foregoing description relates to the conformation of the stacked plates of the rotor 4. But it is quite obvious that the rotary distributor can have a similar configuration instead of that with blades described with reference to FIGS. 1 and 11. Thus, and by way of example only, the rotary distributor may comprise at least two plates according to any one of the profiles of FIGS. 5 to 7 or at least one plate according to the profile of FIG. 10; in this case, the plates in question constitute the first stage of the rotor 4 comparable to fictitious blades.

It is now a question of exposing the means implemented to ensure that the particles subjected to the very intense centrifugal forces which reign in the living veins 19 escape and migrate from the latter towards the dead blades. First of all, it is very important to note that it is possible to reduce the path length of the heavy particles from the center to the periphery in a living vein 19, by intervening on the conformation of the cross section of the considered vein, cross section which depends on the shape and orientation of the openings which define the envelope of said vein.

Consequently, and if one refers to the embodiments illustrated in FIG. 13, the cutouts 15 can be, as indicated in: - 28, trapezoidal windows, the large base of which is near the periphery and the small base near the center (representation in solid line), - 29, trapezoidal windows, the large base of which is located near the center and the small base near the periphery (representation in broken line), - 30, narrow slits with substantially parallel edges (representation in phantom).

In all these cases, the openings extend without interruption from the center to the periphery and are delimited by rectilinear edges; but it is quite obvious that the edges in question can be broken in zigzag or curved according to the law of trapping which appears necessary.

On the other hand, and still with reference to FIG. 13, the openings can be radial (representation in phantom line) or else inclined in a rectilinear or curvilinear manner so that their peripheral end is in advance (representation in solid line) or behind (representation in broken line) with respect to their central end , if we consider their direction of tangential scrolling T.

The preceding examples show that the inclination, the width and the conformation of the openings make it possible to determine with precision the collection time of heavy particles by the dead blades.

In certain cases, and in particular when the diameter of the plates is relatively large, it is advantageous to reduce the radial extent of the openings. To this end, and as emerges from FIG. 14, openings 31 or 32 of small length are distributed in several concentric annular areas 33 to 36.

In the embodiment illustrated by the left half of FIG. 14, the openings 31 are slots with parallel edges which have, from one area to the next of the same plate, a substantially constant average width and spacing. The density of distribution of the living veins is substantially uniform and the collection time for heavy particles is reduced because a central deflector 37 extending the marginal rims 38 prevents the heavy particles escaping from the living veins. an annular beach remix with the vivid veins of the neighboring outer concentric beach; on the contrary, the deflectors in question direct the heavy particles in flight towards the dead blades of the outer annular area considered.

In the embodiment shown on the right half of FIG. 14, the openings 32 are trapezoidal windows which, from one beach to the next of the same plate, are located on common radii, either that they coincide with these, or that they form an angle of positive or negative impact; the average width and spacing of these windows increase from the center to the periphery, if we go from one annular area to the next. As in the previous case, the edges 38 of the windows have central deflectors 37 opposing the remixing of the separated heavy particles.

It is obvious that the openings can be distributed in annular areas overlapping one another, in order to better standardize their density and to better guard against the risks of remixing.

At the exit of the openings 15 of the last downstream plate of the rotor 4, the live veins 19 composed of the treated mixture free from heavy particles tend to continue their flow following the aforementioned helical paths.

However, the method provides for straightening these helical flows to transform them at the outlet of the rotor 4 into an absolute axial flow towards the fan 2. Such an arrangement is particularly advantageous, since the kinetic energy of rotation of this treated mixture can easily be obtained. recovered to drive the coupled devices 2, 4 and 5 in rotation and thus reduce the power consumed.

To this end, the last downstream plate of the rotor 4 is integral with the action turbine 3, the profile of which is adapted to the particular helical flows mentioned above so that the latter become substantially axial.

In the embodiment shown in Figs. 1 and 12, the action turbine 3 comprises a plurality of blades 39 whose concavity 40 opens upstream of the flow of the mixture in the direction of arrow E. The leading edge 41 of each blade coincides with the rear edge or rim 18 of the solid part 16 of which the blade considered is integral and which delimits the cutout 15 into which said blade opens; moreover, this leading edge 41 is inclined along the slope relative to the sharp veins 19. Of course, the curvature of the concavity 40 and the conformation of the trailing edge 42 are established as a function of the aero- or hydrodynamic characteristics of the vehicle. mixture and operating speed.

Furthermore, the conformation of the blades 39 is such that they channel, towards the periphery where said blades are open, the residual traces of heavy phase.

The preceding description shows that the aero- or hydrodynamic flow of the mixture through the apparatus undergoes, between upstream and downstream, an increasing variation in speed; consequently, an expansion occurs naturally within the rotor and consequently a drop in temperature which can be used to condense a vapor phase during the separation.

The method and apparatus are applicable to the removal of oily mists, such as those generated by machine tools, presses, certain heat treatment furnaces, to the removal of solvent mists in baking ovens or on coating stations, for example, for the elimination of aqueous mists possibly loaded with lye and other toxic product, for very thorough washing of dusty gas with a small quantity of water, for the extraction of traces of the liquid pollutant light in aqueous phases such as waste water from petroleum refineries, to very thorough clarification of liquid phases loaded with heavy pollutants, etc.

Claims (23)

1. Centrifugal separation method applicable to a mixture of phases of any states, characterized in that the mixture is rotated at an angular speed greater than that of a rotating assembly (4) that this mixture must pass through, in that that the mixture is divided into a plurality of veins (19) flowing in helical paths through the rotating assembly and at a tangential speed greater than that of the latter, in that these living veins (19) are separated by dead intermediate helical fluid blades (20) held captive by this rotating crew, in that the heavy phase or phases ejected from the live veins by the centrifugal field of these are trapped by the dead blades, in that the phase or phases heavy trapped in the dead blades and subjected to the centrifugal field which reigns in the latter by being lower than that established in the veins, move towards the periphery, and in that the heavy phase or phases, has traveling in the dead blades are guided by the moving equipment. 2. Method according to claim 1, characterized in that the mixture is subjected, for its upstream rotation, on the one hand, to the action of the rotating assembly and, on the other hand, to a downstream axial suction or to an upstream axial discharge through this equipment, the resulting upstream pressure drop being transformed into a helical speed whose tangential component is superimposed on the tangential speed of said rotating equipment and whose axial component generates the flow. 3. Method according to one of claims 1 or 2, characterized in that the helical flow of the mixture is straightened downstream to be transformed into an absolute axial flow, and in that the kinetic energy of rotation of the treated mixture is recovered to drive the rotating crew in rotation and thus reduce the power consumed by them. 4. Centrifugal separating device implementing the method according to one of claims 1 to 3, characterized in that it comprises, arranged coaxially and moved in rotation in a fixed enclosure, a first device constituted by a fan (2), a compressor or a pump, generating a vacuum upstream, a second device constituted by a rotary distributor (5) transforming the pressure drop, which results from the action of the first device on the upstream pressure, into a rotation speed of the mixture adding in the same direction to the positive speed of rotation of the distributor, and a third device located downstream of the second and consisting of a rotor (4) comprising guide elements (13, 15) of the live veins which direct and channel these on at least part of their course, trap elements (16), which trap the dead fluid blades and capture the heavy phase or phases and which, while opposing the exhaust of the phase or phases lo urdes towards the veins, participate in the progress of this or these heavy phases towards the periphery. 5. Apparatus according to claim 4, characterized in that it also comprises, downstream of the rotor (4), if we consider the flow of the mixture, a fourth device consisting of an action turbine (3) whose profile is adapted to this particular helical flow so that it becomes substantially axial, the blades also channeling the residual traces of heavy phase towards the periphery. 6. Apparatus according to claim 5, characterized in that at least some of the four devices are coupled together (6) and connected to a common device for driving in rotation. 7. Apparatus according to claim 4, the rotor (4) comprises at least two coaxial plates of revolution (13), spaced from one another and delimiting openings (15) which extend from the center towards the periphery , are separated for the same plate by solid parts (16) and are, seen in plan, angularly offset from one plate to the next, characterized in that the edges (17, 18) of the openings of the rotor strictly delimit the envelopes spiral veins (19) multiple helical and concomitantly those of the dead blades (20) which separate them, and in that the angular offset of the plates, the spacing thereof as well as the shape and dimensions of the openings are chosen to determine the relative slope (a) of said living veins, and thus the separating power and the flow rate of the device. 8. Apparatus according to claim 7, characterized in that prominent elements, such as flanges (18, 25; 18a, 25a; 18b, 25b) or ribs (26, 27), integral with the solid parts (16), protrude exclusively in the dead blades (20), on the one hand, to trap them on the edge of the living veins and, on the other hand, to confine the heavy phase or phases which escape from the latter in said dead blades and or guide them to the periphery. 9. Apparatus according to one of claims 7 or 8, characterized in that, in order to reduce the length of the substantially radial path of the heavy phase or phases in the sharp helical veins, the openings (28, 29) are inclined on the spokes . 10. Apparatus according to one of claims 7 to 9, characterized in that the openings are located in the same plate, on several concentric annular pads (33 to 36), possibly in partial overlap to tend to standardize their distribution density and thus reducing the time for collection of the heavy phase or phases by the adjacent dead blades. 11. Apparatus according to claim 10, characterized in that each cutout has at least one lateral flange (38) extended by a central deflector (37), these projecting elements opposing the resuspension in the living veins of the or heavy phases which move towards the periphery in the bundle of dead blades extending between the center and the marginal edge of the corresponding plate. 12. Apparatus according to claim 11, characterized in that the openings are slots (31) which, from one range to the next of the same plate, have a substantially constant average width and spacing. 13. Apparatus according to claim 11, characterized in that the openings are trapezoidal windows (32) which, from one range to the next of the same plate, are aligned on common radii, the average width and spacing of these windows growing from the center to the periphery, from one beach to the next. 14. Apparatus according to claim 4, the rotary distributor (5) of which comprises at least two coaxial plates of revolution (13), spaced from one another and delimiting openings (15) which extend from the center towards the periphery, are separated for the same plate by solid parts (16) and are, seen in plan, angularly offset from one plate to the next, characterized in that these openings of the distributor are each bordered by a single flange or blade ( 18) protruding on the upstream face of the neighboring solid part, if we consider the flow of the mixture, and behind, if we consider the rotation of the plates or, in equivalence (25), on the downstream face and forward. 15. Apparatus according to claim 4, in which the rotary distributor (5) comprises at least one plate of revolution (13) delimiting openings (15) separated by solid parts (16), characterized in that the openings in the distributor are bordered each by two flanges or blades (18, 25) projecting upstream rear and downstream front, respectively on either side of the plate concerned, if we consider the flow of the mixture. 16. Apparatus according to one of claims 14 or 15, characterized in that the flanges or blades (18, 25) are substantially perpendicular to the plate (13) to which they belong. 17. Apparatus according to one of claims 14 or 15, characterized in that the flanges or blades (18a; 25a; 18b and 25b) are inclined substantially in correspondence with the chosen slope of the living veins in flow relative to the rotor. 18. Apparatus according to claim 4, characterized in that the rotary distributor (5) is an impeller constituted by a plurality of vanes (21) oriented from the center towards the periphery and whose concavity (23) opens towards the downstream if we consider the flow of the mixture, the trailing edge (22) of each blade being inclined appreciably in correspondence with the chosen slope of the vivid veins in flow relative to the rotor. 19. Apparatus according to claim 18, characterized in that the trailing edges (22) of the blades (21) are integral with a disc (13) coupled to the rotor (4) and limit the openings (15) of this disc in rear if we consider the rotation of said rotor. 20. Apparatus according to claim 5, characterized in that the action turbine (3) comprises a plurality of blades (39) oriented from the center towards the periphery and whose concavity (40) opens upstream if the 'We consider the flow of the mixture (E), the leading edge (41) of each blade being inclined substantially in correspondence with the chosen slope of the vivid veins in flow relative to the rotor. 21. Apparatus according to claim 20, characterized in that the leading edges (41) of the blades (39) are integral with the last downstream disc (13) of the rotor (4), if one considers the flow of the mixture , and limit openings (15) of this disc forward, if we consider the rotation of said rotor. 22. Apparatus according to one of claims 4 to 21 characterized in that it comprises flat plates (13) and perpendicular to the axis of rotation. 23. Apparatus according to one of claims 4 to 21, characterized in that it comprises frustoconical plates (14) and converging downstream of the flow of the mixture. The present invention relates to a centrifugal separation process for a mixture of phases of any states: gas in gas, liquid in gas, powdery solid in gas, liquid in liquid, powdery solid in liquid or other combinations of three phases between them. It also extends to an apparatus for implementing this method. US Pat. No. 3,234,716 describes a centrifugal separating device comprising a rotor constituted by a stack of frustoconical plates having openings arranged facing each other to form chimneys. The mixture to be treated is driven at the same angular speed as the rotor; it flows radially, the light phase towards the center and the heavy phase towards the periphery. In addition, a transfer of mixture occurs between the plates through the chimneys, but the transfer circulation is axial and does not induce any force adding to the centrifugal force. French patent No. 1568746 also describes a centrifugal separating device comprising a stack of plates, the orifices of which are angularly offset from one plate to the next so that the phases travel radially between two plates and in a zigzag in an axial direction. from one plate to the next. A force field is added perpendicular to the centrifugal field, but does not overlap with it to intensify the field due to the rotor alone; in addition, the paths of the mixture are, in superposition, tangential and axial in zigzag and not helical by inducing to the mixture animated with the rotor an angular speed Higher than that of the rotor. The present invention aims to generate within the mixture an extremely intense centrifugal field and much higher than that to which is subjected a rotating assembly participating in the treatment. Consequently, the manufacture of this rotating assembly is thereby simplified and can use inexpensive economic techniques used in the field of centrifugation, for example the molding of rotating plastic parts. Furthermore, due to the high intensity of the centrifugal field, the separation of the phases can be improved even when their specific masses are very low and very close to one another. Concomitantly, the aerodynamic phenomena can be such that a significant part of the kinetic energy of centrifugation can be recovered, with a view to reducing the overall energy consumption and thus improving the economic efficiency of the treatment. These same phenomena can generate, by thermodynamic effect, cooling within the moving mass, which can be beneficial in particular for condensing a vapor phase. According to the invention, the centrifugal separation process is characterized in that the mixture is driven in rotation at an angular speed greater than that of a rotating assembly that this mixture must pass through, in that the mixture is divided into a plurality of veins flowing in helical paths through the rotating assembly and at a tangential speed greater than that of the latter, in that these living veins are separated by dead intermediate helical fluid blades held captive by this rotating assembly, in that the heavy phase or phases ejected from the live veins by the centrifugal field thereof are trapped by the dead blades, in that the heavy phase or phases trapped in the dead blades and subjected to the centrifugal field which prevails in the latter , being lower than that established in the veins, move towards the periphery, and in that the heavy phase or phases moving in the dead blades are guided pa r the moving crew. Alternatively, the mixture may be subjected, for its upstream rotation, on the one hand, to the positive action of the rotating assembly and, on the other hand, to a downstream axial suction or to an upstream axial discharge through this equipment, the resulting upstream pressure drop being transformed into a helical speed whose tangential component is superimposed on the tangential speed of said rotating equipment and whose axial component generates the flow. In addition, the helical flow of the mixture can be straightened downstream to be transformed into an absolute axial flow and the kinetic energy of rotation of the treated mixture is recovered to rotate the rotating assembly and thus reduce the power consumed by that -this. According to the invention, the apparatus implementing the method is characterized in that it comprises, arranged coaxially and moved in rotation in a fixed enclosure, a first device constituted by a fan, a compressor or pump, intended to generate a upstream depression, a second device constituted by a rotary distributor transforming the pressure drop which results from the action of the first device on the upstream pressure into a speed of rotation of the mixture adding in the same direction to the positive speed of rotation of the distributor, and a third device located downstream of the second and consisting of a rotor comprising elements for guiding the live veins which direct and channel them over at least part of their course, trap elements which trap the fluid blades dead and capture the heavy phase (s) and which, while opposing the escape of the heavy phase (s) to the veins, participate in the progression of this o u of these heavy phases towards the periphery. Alternatively, the device may comprise, downstream of the third device or rotor if the flow of the mixture is considered, a fourth device constituted by an action turbine whose profile is adapted to this particular helical flow so that it becomes substantially axial, the blades also channeling the residual traces of heavy phase towards the periphery. In addition, at least some of the four devices can be coupled together and connected to a common rotational drive device. According to a particularly advantageous embodiment, the rotor comprises at least two coaxial plates of revolution, spaced from one another and delimiting openings which extend from the center towards the periphery, are separated for the same plate by parts solid and are, seen in plan, angularly shifted from one plate to the next; the edges of the openings of the rotor rigorously define the envelopes of the multiple sharp helical veins and, concomitantly, those of the dead blades which separate them; the angular offset of the plates, their spacing as well as the ** ATTENTION ** end of the CLMS field may contain start of DESC **.