EP0815929B1 - Static mixer - Google Patents

Abstract

A static mixer has a bundle of chambered passages (A,B,C.) which include at least some chambers which bring about a mixing effect. The bundle is located inside a tube, and the mixing chambers are arranged in a series extending in the direction of the axis of the tube, each chamber being bounded by two transverse end walls. Two adjacent side walls of the mixing chambers have four openings (a1, b1,a2,b2) arranged on alternate sides, which create connections with two upstream (A1,B1) and two downstream chambers (A2,B2). Between at least two sections of the mixer which contain mixing chambers, are placed transfer chambers (S1,S2,) which have two closed ends and three side openings to adjoining chambers.

Description

The invention relates to a static mixer with a Bundle of chambered strands.

In the not pre-published EP-A-0 749 776 is a static mixer described on a principle similar to that well-known Multiflux and ISG mixer works; For however, its production becomes much less material needed. Such a mixer, which is advantageous for Treatment of highly viscous media is used consists of a tube and a variety of in it Pipe arranged mixing elements. Each of the mixing elements includes two axial sections, each section at least one divider dividing the section assigned. The dividers of the two sections intersect and divide the pipe cross section into Subareas that are essentially the same size. At the boundary between the sections are open as well Sub-areas covered by deflection disks are provided and in such a way that exactly on both sides of each divider an open partial area is arranged. In terms of successive mixing elements exist Relationships that on the one hand neighboring dividers cross and on the other hand the open areas are mutually offset.

Those in the above EP-A-0 749 776 Embodiments also correspond to the alternative Definition of the preamble of claim 1. Here is each a mixing-active chamber according to an alternative Assign definition of an open partial area. The two closed chamber ends and the neighboring ones Side walls, the passages to other chambers are contained by the deflection plates or formed by the dividers.

The sets of given by the two definitions static mixers are not identical. But there is Subsets of these quantities, for the mixer of which both Definitions apply. The exemplary embodiments mentioned are elements of the subsets.

Multiflux mixers contain a linear arrangement of Mixing elements, each with two channels. Everyone of these channels continuously narrows in Flow direction to the middle of the mixing element (Confuser); it widens behind the narrowest part again continuously (diffuser) in a 90 ° rotated level. A flowing through the mixing element Medium undergoes a transformation through which the number of partial layers doubled. This transformation continues together from a "cutting" of the medium at the entry into the mixing element in two partial flows, a "upsetting" (in Confuser), a "spread" (in the diffuser) and one Merging the partial streams. Ideally, this is done "Cutting" in such a way that a current with a uniform layering perpendicular to the layers is cut so that after the forming continues an even stratification - with a doubled number Sub-layers - present.

In the mixing-active chambers of the generic mixers the treatment to be treated is carried out accordingly Media, but without confusors and Diffusers are necessary for this transformation.

When mixing two media, the different values of viscosity, deviations from the ideal mixing mechanism: after passing through several Mixing elements are sub-layers on the edge of the Layering are much thicker than the rest Sub-layers.

It is an object of the invention, the generic Modify mixer so that deviations from the ideal mixing effect at least partially eliminated become. This task is solved in that in Mixers "rearrangement chambers" are provided by the is achieved that marginal sub-layers in the Interior of the stratification. Claim 1 defines such a mixer with rearrangement cells. The dependent claims 2 to 11 relate to different embodiments of the inventive Mixer.

Fig. 1

einen Abschnitt einer Mischerstruktur, die nur mischwirksame Kammern aufweist,

Fig. 2

den geometrische Aufbau der Mischerstruktur gemäss Fig.1,

Fig. 2a

einen Querschnitt durch die Struktur der Fig.2,

Fig. 3

eine erste Modifikation der in Fig.1 gezeigten Mischerstruktur,

Fig. 4

eine zweite Modifikation,

Fig. 5

eine erste erfindungsgemässe Mischerstruktur mit Umlagerungskammern,

Fig. 6

eine zweite erfindungsgemässe Mischerstruktur mit Umlagerungskammern,

Fig. 7

eine Abwicklung der an der Peripherie gelegenen Kanten der Mischerstruktur gemäss Fig.1 in die Ebene,

Fig. 8

eine entsprechende Abwicklung für eine Mischerstruktur gemäss Fig.5,

Fig. 9

eine Abwicklung für eine Mischerstruktur gemäss Fig.6,

Fig. 10

eine Mischerstruktur mit einem zusätzlichen vorteilhaften Strukturelement,

Fig. 11

eine erste seitlich verstärkte Mischerstruktur,

Fig. 12

eine zweite Mischerstruktur mit seitlicher Verstärkung,

Fig. 13

eine schematische Darstellung zu einer Mischerstruktur mit einem Bündel von vier gekammerten Strängen,

Fig. 14

eine schematische Darstellung zu einer Mischerstruktur mit neun gekammerten Strängen und

Fig. 15

eine schematische Darstellung zu einer Mischerstruktur mit sechzehn gekammerten Strängen.

The invention is explained below with reference to the drawings. Show it:

Fig. 1

a section of a mixer structure which has only mixing-effective chambers,

Fig. 2

the geometric structure of the mixer structure according to FIG. 1,

Fig. 2a

3 shows a cross section through the structure of FIG. 2,

Fig. 3

a first modification of the mixer structure shown in Figure 1,

Fig. 4

a second modification,

Fig. 5

a first mixer structure according to the invention with rearrangement chambers,

Fig. 6

a second mixer structure according to the invention with rearrangement chambers,

Fig. 7

development of the edges of the mixer structure located on the periphery according to FIG. 1 into the plane,

Fig. 8

a corresponding processing for a mixer structure according to FIG. 5,

Fig. 9

a processing for a mixer structure according to Figure 6,

Fig. 10

a mixer structure with an additional advantageous structural element,

Fig. 11

a first laterally reinforced mixer structure,

Fig. 12

a second mixer structure with side reinforcement,

Fig. 13

1 shows a schematic representation of a mixer structure with a bundle of four chambered strands,

Fig. 14

a schematic representation of a mixer structure with nine chambered strands and

Fig. 15

a schematic representation of a mixer structure with sixteen chambered strands.

The static mixer shown in Fig.1 consists of a mixer structure 1 arranged in a tube 10 is. The mixer structure 1 is composed of mixing elements 1 'together, each consisting of two dividers 2, 2' and there are two deflection disks 3, 3 '. At the level of Deflection disks 3, 3 'are two open Subareas 4, 4 '(outer boundaries 4a, 4a'), which are also known as Through holes have been designated.

The geometric structure of the mixer structure 1 - see Figures 2 and 2a - can be viewed as one in the z-axis direction oriented bundle of chambered strands A, B, Describe C and D. The names for the chambers are A1, A2, ... B1, B2, ... C1, C2, ... and D1, D2, ... These chambers are "mixed"; they extend into Direction of the tube 10 between two closed Ends e1, e2, and two adjacent side walls the mixing chamber contain four alternate arranged passages a1, b1, a2 and b2 (with each areas marked with a cross in Fig. 2). The chamber C2 is through passages a1 and b1 with the two upstream chambers A1, B1 and via the Passages a2 and b2 with the two downstream Chambers A2, B2 connected. All are in the mixer of Fig.1 Mixing chambers. In general, however, one Mixing chamber also with other chambers (Rearrangement or intermediate chambers, see below) be connected.

The strands A and B - to be seen as cross sections in Fig.2a - have the same structure; by a 180 ° turn the z-axis (or center line 5) can be used with strand A. the line B are brought to congruence. The same Relationship exists between strands C and D. The Strands of a pair A, B are each with the another strand pair C, D via the chamber passages a1, ... connected. The two strand pairs differ in that the chambers of one versus those of another offset by half a chamber length in the z direction are arranged.

Arrows 6a, 6b, 7a and 7b in FIG. 1 indicate reshaped like the medium to be mixed in chamber C2 becomes. Two media flows emerge from strands A and B. through the entrance passages a1 (arrows 6a, 6b) and a2 (Arrows 7a, 7b) in the chamber C2 and thus in the strand C a, unite there and influence each other simultaneously moving through chamber C2. On the edge 20 at the exit passage a2 takes place Separation of a first partial flow (arrows 6a, 7a), the enters strand A. The remaining partial flow (Arrows 6b, 7b) enters via the exit passage b2 strand B. Ideally, there is an even one Redistribution, as indicated by the arrows, where each arrow has an equal amount transported mix corresponds.

The chambers of the mixer structure 1 are essentially cuboid and the passages rectangular. The walls are plate-shaped. The walls have to not have constant wall thicknesses. You can for example, be wedge-shaped, as shown in Fig.3 is illustrated.

So that the generated in the mix by the mixer structure Pressure drop is smaller than with the mixer structure Fig.1, curved shapes can also be used for the walls be provided, as shown in Fig.4.

In addition to the mixing-effective chambers, the contains Mixer structure 1 according to the invention “rearrangement chambers” S1, S2 - see Fig. 5 - and S1 ', S2' (not in Fig. 5 visible). The chamber S1 has two entry passages a1 and b1 and an exit passage t1. The passage t1 forms the connection to an intermediate chamber T (or Transfer chamber), which has only one entry, namely the Passage t1, and an outlet t2 (not visible) having. A is arranged diametrically to T. corresponding intermediate chamber T 'with an access t1' and an exit t2 '. Lead the intermediate chambers T and T ' continue to rearrangement chambers S2 '(not visible) or S2, each having an entry passage and contain two exit passages. For S2 these are Passages with t2 'or a2 and b2 designated passages. Chambers S1 and S2 ' or S1 'and S2 each form one by one Transfer chamber T, T 'connected pair. In these A rearrangement of the stratification takes place in pairs of chambers, to improve the mixing quality according to the invention leads. In the second rearrangement chamber S2, S2 'takes place another mixing step takes place simultaneously.

6 shows a second embodiment of the Mixer structure according to the invention, in pairs existing rearrangement chambers S1, S2 'and S1', S2 are immediately adjacent.

Based on the oblique images of Figures 1, 5 and 6 Networking of the individual chambers is difficult or even impossible not visible in their entirety. This networking can be made easily recognizable by the Mixer structures 1 over their scope in the plane unwinds. Such developments are in Figures 7 to 9 shown. The two side edges that are parallel to the z-axis, are in each case by the strand B with the chambers B1, B2, B3, ... in Fig. 7, B1, T ', B2, ... in Fig. 8 and B1, S1 ', B2 ... in Fig. 9.

Make the meandering lines in Figures 7 to 9 represent the outer wall edges of the mixer structures 1 outer corners of the deflection plates 3, 3 '(Fig.1) not marked; they are in the middle of each horizontal stretches of meandering lines. By Arrows indicate the flow of the mix: diagonally arrows standing at the entry points of the chambers, horizontal at the exit points. In Fig. 7 (cf. Fig.1) all chambers are equivalent; there are Mixing chambers. In Fig. 8 are particularly those Chamber arrangements S1 - T - S2 'and S1' - T '- S2 too note (see Fig. 5). In Fig. 9 there are especially those Chamber arrangements S1 - S2 'and S1' - S2 must be observed (cf. Fig. 6).

Fig. 10 shows another means by which a contribution to The object of the invention can be achieved can. It is the following: most of the Passages between neighboring mix-active chambers are laterally limited by the tube 10; to Flow control are individual passages by a rib 11 arranged in the tube 10 limited. Through this rib 11 is mixed material that along the pipe wall flows into the interior of the pipe 10 redirected. This improves the mixing quality.

As a rule with the mixer according to the invention highly viscous media are treated, large Pressure gradients in the direction of the z-axis along the Mixer structure 1. These pressure gradients decrease, if the wall thicknesses are reduced. With thin Walls of the mixer structure 1, however, there is Danger of the structure being crushed. With suitable The mixer structure 1 in can be reinforced bring a more stable shape. Figures 11 and 12 show Reinforcements by strips 12 and 13 on the Periphery of the mixer structure 1 arranged in the z direction are. Such reinforcements can of course also be used for Provide mixer structures that are not according to the invention Transfer chambers included.

Figures 1 to 12 relate to mixers whose Mixing chambers are arranged in four strands. Such a mixer corresponds to the first Embodiment that in the aforementioned Registration has been described; he is in the schematic representation chosen there again in Fig. 13 shown. The other two embodiments are shown in Figures 14 and 15.

In Fig. 13 the two upper levels represent the limits between adjacent axial sections that represent the Have mixing elements. There are two open ones as well as two covered by deflection disks 3, 3 ' Partial areas; and the open partial areas 4, 4 ' offset from each other. The lower level gives the designations A, B, C and D of the four chambered Strands on. The same applies to the mixer Figures 14 and 15.

Mixers according to Fig. 14 contain bundles of nine in Strands arranged in the direction of the tube, six of these strands, namely A, C, B, D, B 'and C', contain mixing-effective chambers and the remaining three Strands that are not labeled, intermediate chambers contain the indirect connections between produce mixing-effective chambers. The in the corner strands have arranged intermediate chambers - like the one above called transfer chambers T and T '- two each Passages to neighboring chambers. The intermediate chambers the central strand each contain four Passages that are arranged in a ring.

Mixers according to Fig. 15 contain bundles of sixteen in Strands arranged in the direction of the tube, being eight of these strands, namely A, C, B, D, A ', B', C 'and D', contain mixing-effective chambers and the remaining eight Strands contain intermediate chambers that are indirect Establish connections between mixing-effective chambers. The intermediate chambers point again as in the example of Fig. 14 two or four passes to neighboring Chambers on.

The mixer according to the invention can be manufactured that the bundle of chambered strands A, B, ... in shape a monolithic, especially by injection molding manufactured structure is present.

Claims (10)

1. Static mixer with a bundle of chambered strings (A, B, ...) which at least partly comprise mixing-active chambers (A1, A2, ...), with the bundle being arranged in a tube, the mixing-active chambers extending in the direction (5) of the tube in each case between two closed ends (e1, e2), and two mutually adjacent side walls of the mixing-active chambers (C2) containing four alternately disposed passages (a1, b1, a2, b2) which produce connections to two chambers lying upstream (A1, B2) and to two chambers lying downstream (A2, B2) respectively, wherein chambers are furthermore arranged between at least two sections of the static mixer which contain mixing-active chambers, namely re-layering chambers (S1, S1', S2, S2') which have two closed ends and three lateral passages to adjacent chambers.
2. Mixer in accordance with claim 1 characterised in that the re-layering chambers (S1, S1', S2, S2') occur in pair-wise connection and that a direct or an indirect connection between them is provided via one of the passages in each case.
3. Mixer in accordance with claim 2 characterised in that the pair connections at least of individual re-layering chambers is provided indirectly via an intermediate chamber (T) that has two closed ends and two lateral passages.
4. Mixer in accordance with one of the claims 1 to 3 characterised in that the bundle has four chambered strings (A, B, C, D), in that all mixing-active chambers (A1, ...) are substantially formed alike and in that adjacent strings connected via chamber passages contain chambers which are each arranged so as to be displaced by half a chamber length in the direction of the tube with respect to one another.
5. Mixer in accordance with one of the claims 1 to 3 characterised in that the bundle has nine chambered strings (A, B, B', C, C', D, ...), six of these strings comprising mixing-active chambers and the remaining three strings containing intermediate chambers which produce indirect connections between mixing-active chambers.
6. Mixer in accordance with one of the claims 1 to 3 characterised in that the bundle has sixteen chambered strings (A, A', B, B', C, C', D, D', ...), eight of these strings comprising mixing-active chambers and the remaining eight strings containing intermediate chambers which produce indirect connections between mixing-active chambers.
7. Mixer in accordance with one of the claims 1 to 6 characterised in that most of the passages (a1, ...) between adjacent mixing-active chambers (A1, ...) are laterally bounded by the tube (10); and in that some individual passages are in each case bounded by a rib (11) arranged at the tube for deflecting the flow.
8. Mixer in accordance with one of the claims 1 to 7 characterised in that the chambers (A1, ...) have substantially the form of rectangular prisms and the passages (a1, ...) are substantially rectangular.
9. Mixer in accordance with one of the claims 1 to 8 characterised in that the bundle of chambered strings (A, ...) is reinforced by strips (13) which are arranged at the periphery of the bundle in the direction of the tube (10).
10. Mixer in accordance with one of the claims 1 to 9 characterised in that the bundle of chambered strings (A, ...) is present in the form of a monolithic structure, in particular one produced by injection moulding.

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