DE3027433A1 - Pressure diffusion sepn. method for mixts. - uses perpendicular identical frequency wave fields with differing phases - Google Patents

Abstract

The sepn. of mixts. of two gases, two liqs., a gas with a colloid, or a liq. with a solid, and based on differing molecular weights or specific gravities is effected by pressure diffusion using varying pressure fields. These fields are two-dimensional mutually perpendicular wave fields operating at the same frequency but with pi/2 phase shift. The mixt. for sepn. is fed by co-current or counter-flow perpendicular to the vibration plane along the longitudinal axis of a prismatic sepn. chamber with the sepd. components leaving at the roof of the chamber. The wave-fields can be formed by two vibrating walls, each tuned to the natural frequency of the standing waves. A circular polarised wave field produced by a single vibrating wall and reflecting wall, or by tubular valves, may be used. The method separates a variety of mixtures, in particular gaseous isotopes, with high efficiency and low power consumption. No moving parts or pressure compressors are involved.

Description

The invention relates to a method of separation

of mixtures due to different molecular or.

specific gravity with gaseous / gaseous, gaseous / colloidal, liquid / liquid or # 1 liquid / solid components.

Such physical separation processes are known per se.

They are essentially using ultracentrifuges, mass spectrographs or partition wall diffusion, thermal diffusion or separation gas diffusion etc.

In relation to the required separation work, the ultracentrifuge is used here all other aforementioned separation processes by an order of magnitude better, only prevented a number of technically unsolved problems, especially the critical resonance vibrations, one Implementation of the ultracentrifuge against partition wall diffusion.

Separation occurs in the ultracentrifuge due to pressure diffusion in a field with stationary pressure gradients. This pressure gradient is also the Maintain steady radial centrifugal acceleration.

However, the aforementioned methods can only be used for special types of states of the mixture to be separated. This has an effect on centrifuges, for example the vibration instability is a disadvantage, and in the case of diffusion systems the high one Energy expenditure.

The present invention is based on the object of a method of the type mentioned at the outset, which can be applied once to all three types of state On the other hand, there is a mixture separation without mechanically moving parts and without pressure compressors permitted.

This task is accomplished by the measures laid down in the claims solved in an optimal way. The following description includes exemplary embodiments dealt with and shown schematically in the drawing. There Fig.la show a Cross-section in the X-Y plane of the basic design in a schematic representation, Fig.lb a longitudinal section according to Fig.la, Fig.2 a cross section through a separation chamber with coincidence excitation, Figure 3 shows a cross section through a separation chamber with only one Suggestion, 4 shows a cross section through a separation chamber with pneumatic Excitation, Fig. 5 a separation chamber with curved walls in a schematic representation.

The general idea of the invention sees a solution to the posed Task by means of unsteady pressure fields, especially abbreviated standing ones It is well known that very high alternating accelerations occur in a standing wave field auf.ßei linear oscillations, however, there is an extensive cancellation of a The resulting acceleration. In the crossed wave field, the particles are circular Movements around their rest position, but not on a common center relate.

This results in a centrifugal acceleration, according to the theory the pressure diffusion, however, the segregating diffusion flow is proportional to the acceleration.

For a right-angled crossed (in the X and Y axes), standing Wave field results in the following field distribution of the velocity ~ v ", the acceleration "b" and the pressure t # '1, where the index 11011 denotes the amplitude in each case and AJ is the circular function and k k is the wave number.

v = v sinW t sin kx; v = v cos AS t sin ky Y ob = v OJ cos4> t sin kx x 0 With pressures t pO, which amount to about 1/3 of the base pressure, accelerations can be achieved that approach the ultracentrifuges. Since the resulting acceleration results as a non-linear effect, high pressure amplitudes should also be aimed for for this reason.

For non-rectangular and non-circular wave fields result elliptical motions of the particles. In this case, too, there is a resulting Acceleration component. For the generation and maintenance of standing wave fields there are a number of types of drive.

The most obvious is the one with a boundary wall in the Kind of a piston konphas is periodically reciprocated, with a reflective The excitation frequency is based on the resonance with the standing wall A higher harmonic with several wave trains is expediently tuned stimulated.

The crossed wave that is perpendicular to this is excited analogously Waves have the same frequency and are only shifted in phase by t / 2.

At the proposed excitation of a crossed two-dimensional Wave field by means of coincidence becomes in a plate-shaped waveguide a Bending vibration initiated. This plate radiates energy in a known way With resonance matching of the plate and the separation space results a standing wave field; With a phase shifted by t / 2 Plate results in a crossed field.

With the proposal, a standing wave field by means of pneumatic energy to maintain, is introduced and / or in the cycle in the overpressure mountain pressure medium The medium is taken from the negative pressure mountain are stationary, this can be done by means of fixed tubular ones that are perpendicular to the plane of movement The control is expediently carried out by rotating valves (Slit valves) carried out.

The material to be separated is guided vertically in the field movement the circular oscillation in the X-, Y-plane, the good is moved in the Z-direction. Analog for operation in the centrifuges can be the same or. Countercurrent principle applied Likewise, there is a convection flow in the manner of the Clusius-Di-cl <el'schen Separating pipe to add up the separating effect is possible from different separation stages is also carried out analogously to the centrifuge process.

In the Fig.la, lb is now an embodiment for demonstration The working principle is shown in the separation chamber 1 that is to be separated Mixture, for example a gaseous isofropene mixture. The separation chamber 1 provides a prismatic right-angled space. A side wall 2 is periodically in The resonance of a standing wave is excited in the x-direction Wall 4 is fixed and is on optimal reflection with low reflection loss When using metallic materials, the wafld surface behaves a plastic cover to dissipate the so-called unavoidable absorption door Plastic coating should continue to have a low thermal diffusivity.

In the same way, an oscillating wall 3 and a fixed wall 5 also form a standing wave in Y-direction of the same frequency, but with t # / 2 phase shift.

In the illustrated embodiment, the oscillating walls 2 and 3 driven by an electromagnetic moving coil system 7. Advantageously the oscillating walls are supported by springs 6 and operated in resonance. They oscillate The material to be separated flows perpendicular to the x-y oscillation plane in the z-direction. With direct current operation, the mixture is at the base 8 introduced and the components removed from the top surface 9 through channels # 10 ". Here the lighter component collects along the lines sink x = sink y = 1 and the heavier component at sin kx = sin k y =. Here x and y are each from the associated wall pairs measured with "k" the wave number 2 g / 2 is designated standing waves the condition applies that the wavelength i # is a whole multiple the wall clearance is.

You can see the operating modes and circuits on the ultracentrifuge analogously transferred to this case, if one has a square oscillation cell in each case that extends from vibration node to vibration node, as a tube centrifuge Therefore, a description of the operation according to the countercurrent principle should be and the various series connections are unnecessary.

In Fig.2 is an example of a separation system with a coincidence drive A prismatic separation chamber 11 is formed by two perpendicular to each other standing fixed wall pairs 14 and 15 limited.

The walls are each designed to be optimally reflective.

In the separation chamber 11 there are two mutually crossed plates 12,13. These are e.g. due to an alternating torque from torque sensors 17 to Bending vibrations are excited. If the coordinate orientation is analogous to that in Fig.l adopted and described example, a plate swings in x- and the other in y-direction. In z-direction the oscillation is conphas (2-dimensional field). By determining the bending wavelength on the plates the dimensions of the separation chamber can be a standing one in a manner known per se Maintain wave field. A crossed field is obtained again by a phase shift around # / 2.The supply of the mixture to be separated and the discharge of the separated components takes place analogously to Fig. 1 on the base and the top surface.

3 shows an embodiment with only one excitation mechanism Separation chamber 21 consists of fixed ones that are not at right angles to one another Walls 24.

Only one wall side 22 is periodic, here by an eccentric drive 27 symbolizes, stimulates. Thanks to the non-orthogonality, it becomes original Vibration running in one direction (e.g. y-direction) deflected in the x-direction, see above that there is also a crossed two-dimensional standing wave field the wall distances can be reached areas in which a circular particle movement In the general case for wave fields that are not perpendicular and not shifted by 2/2 - elliptical particle movements result.

4 shows a prismatic separation chamber 31 with fixed, reflective Side walls 35. in which the circular standing wave field with pneumatic energy is maintained; this is done, for example, by moving in the z-direction extending tube 36 with slots 37. An inner tube 38 with slots rotates in the tube 39. In the inner tube 38, the mixture to be separated is fed under pressure.

When the inner tube rotates, pressure medium is periodically drawn into the separation chamber 31 ejected.When adjusting the pulsation frequency to the natural frequencies of the Separation chamber 31 can generate a standing wave field. Circular fields too received, the individual Schitzrohre 36,38 are coordinated in phase.

Finally, the exemplary embodiment according to FIG. 5 will be discussed shows a schematic plan view of a prismatic separation chamber 41 with curved Walls 44. The excitation of a two-dimensional standing wave in the x-y plane takes place by a extending in the z-direction strip piston 42, which is carried out by a Magnetostrictive transducer 47 is driven. The width of the separation chamber 41 is smaller than the excited natural frequency i /2. This means that the medium carries vibrations along the curved line. Corresponding to the radius of curvature g results an acceleration component v 2/9 directed away from the center of curvature; whereby 2 is the mean rapid movement.

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Claims (7)

Process for the separation of mixtures Patent claims. 1. Method of separation of mixtures due to different Molecular or specific weight with gaseous / gaseous'gaseous / colloidal'liquid / liquid or liquid / solid components, in that the pressure diffusion of unsteady pressure fields, in particular two-dimensional ones, perpendicular to one another standing wave fields oscillating at the same frequency with t / 2 phase shift is, such that the mixture to be separated in the cocurrent or countercurrent process perpendicular to the plane of vibration in the longitudinal axis of a prismatic separation chamber is performed, and the supply and discharge lines of the separation mixture and the separated Components are located on the base and top surface of the separation chamber. 2. The method according to claim 1, characterized in that g e k e n n z e i c h -n e t that a two-dimensional standing wave field by arranged at right angles to each other Oscillating walls (2 and 3) each with opposing fixed reflection walls (4 and 5) is achieved'wherein the oscillation frequency of the oscillating walls (2 and 3) to the natural frequency of the standing waves is tuned. 3. The method according to claim 1, characterized in that g e k e n n z e i c h -n e t that a crossed two-dimensional standing wave field by two to each other vertically standing plates (12 and 13) by moment sensors (17) to bending vibrations are excited, the natural frequencies of the plates (12, 13) on the natural frequencies of the standing waves are matched. 4. The method according to claim 1, characterized in that g e k e n n z e i c h -n e t that generates a circularly polarized wave field with only one oscillating wall (22) The reflection walls (24) of a separation chamber (21) are not at right angles to one another are arranged. 5. The method according to claim 1, characterized in that g e k e n n z e i c h -n e t that a circularly polarized wave field through one or more pipe valves (37-39) is achieved, the pressure medium in the cycle of the standing waves in the pressure maximum fed in or the medium is withdrawn at the minimum pressure. 6. The method according to claim 1, characterized in that g e k e n n z e i c h -n e t that in a separation chamber (41) with curved walls ~ 44) a standing wave by means of an oscillating wall (42) is maintained, so that due to the non-rectilinear Oscillating motion results in a resulting centrifugal acceleration. 7. The method according to claim 1, characterized in that the reflection and oscillating walls (2, 3, 4, 5, etc.) with a material with a low thermal diffusivity, e.g. Plastic coated.