DE10123092A1 - Method and static mixer for mixing at least two fluids - Google Patents

Abstract

The invention relates to a method for mixing at least two fluids, according to which a plurality of separate fluid streams of both fluids converge, forming fluid lamellae of alternately adjacent fluids. The convergent fluid lamellae are evacuated in the form of a focalised combined fluid stream. Said focalised combined fluid stream is introduced as a jet of fluid into a swirl chamber, forming a fluid spiral that flows towards the interior. The mixture formed is drained from the centre of the fluid spiral. The micro-mixer is characterised by a swirl chamber (6, 16, 116), into which the focalising channel (5, 15, 35, 45, 105, 105', 115, 115') opens in such a way that the focalised combined fluid stream enters in the form of a jet of fluid and forms a fluid spiral (100) that flows towards the interior. At least one outlet channel (7) that has a fluidic connection to the swirl chamber (6, 16, 116) drains the mixture that has been formed.

Description

The invention relates to a method for mixing at least two fluids according to claim 1 and a static micromixer according to the Preamble of claim 12.

The aim when mixing at least two fluids is to achieve a uniform distribution of the two fluids in a certain, usually as short a time as possible. Static micromixers are particularly advantageously used for this purpose, as shown in the overview by W. Ehrfeld, V. Hessel, H. Löwe in Microreactors, New Technology for Modern Chemistry, Wiley-VCH 2000 , pages 41 to 85. For the mixing of liquids, known static micromixers achieve mixing times between 1 s and a few milliseconds by producing alternately adjacent fluid lamellae with a thickness in the µm range. The mixing of gases takes place much faster due to the higher diffusion constants. In contrast to dynamic mixers, in which turbulent flow conditions prevail, the specified geometry in static micromixers enables the width of the fluid lamella and thus the diffusion paths to be set precisely. The very narrow distribution of the mixing times achieved in static micromixers allows a variety of options for optimizing chemical reactions with regard to selectivity and yield. Another advantage of static micromixers is the reduction in component size and thus the ability to be integrated into other systems such as heat exchangers and reactors. The interaction of two or more components interconnected in such a small space in turn opens up new possibilities for process optimization. The application potential of micromixers extends from liquid-liquid and gas-gas mixtures to the formation of liquid-liquid emulsions, gas-liquid dispersions and thus also to multi-phase and phase transfer reactions.

A static based on the principle of multilamination Micromixer has a microstructured in one level Interdigital structure made of interlocking channels with a width of 25 µm or 40 µm (loc. cit., pages 64 to 73). The two fluids to be mixed through the channels into a variety of separate fluid flows divided, flowing opposite and parallel to each other and alternating are arranged to each other. The neighboring ones are separated by a slot Fluid flows are discharged vertically out of the plane and with each other contacted. Suitable for mass production Structuring methods can be used for the channel geometries and thus the Reduce the width of the fluid lamella to a limited extent in the lower µm range.

A further reduction in the fluid lamellae obtained according to the multilamination principle can be achieved by so-called geometric focusing. Such a static micromixer for converting dangerous substances is described by TM Floyd et al. on pages 171 to 179 in Microreaction technology: industrial prospects; proceedings of the Third International Conference on Microreaction Technology / IMRET3, editor: W. Ehrfeld, Springer 2000 . Alternating adjacent channels for the two fluids to be mixed open in a semicircle radially from the outside into a funnel-shaped chamber that merges into a narrow, long channel. The fluid lamella flow combined in the chamber is hereby transferred into the narrow channel, as a result of which the fluid lamella width is reduced. Under these laminar flow conditions, mixing takes place solely by diffusion, so that mixing times in the millisecond range can also be achieved by reducing the lamella widths in the lower µm range. It is disadvantageous that the narrow channel serving as the reaction space has to be designed with sufficient length with regard to complete mixing, which requires a large design and causes a relatively high pressure loss in this micromixer.

The invention has for its object a method and a static Micromixers are available for mixing at least two fluids make a faster and more even mixing at the same time allow low pressure loss and small installation space.

The object is achieved with a method according to claim 1 and a static micromixer according to claim 12 solved.

In the following, the term fluid is a gaseous or liquid substance or a mixture of such substances understood that one or more solid, can contain liquid or gaseous substances dissolved or dispersed.

The term mixing also includes the processes of dissolving, dispersing and Emulsify. Accordingly, the term mixture includes solutions, liquid liquid emulsions, gas-liquid and solid-liquid dispersions.

Under a variety of fluid flows, fluid lamellae or fluid channels be two or more, preferably three or more, particularly per fluid preferably five or more, fluid flows, fluid lamellae or fluid channels Roger that. Alternating adjacent fluid lamellae or fluid channels means for two fluids A, B that they alternate in at least one plane, one Resulting sequence from ABAB, side by side. The term "Alternatingly adjacent" includes three fluids A, B, C different Sequences such as ABCABC or ABACABAC. The  Fluid fins or fluid channels can also be in more than one plane are alternately adjacent, for example in two dimensions are staggered like a checkerboard. The different fluids Associated fluid lamellae and fluid channels are preferably rectified or arranged in opposite directions parallel to each other. The latter Variant of the flow arrangement is in principle made of microstructured Interdigital structures known from interlocking fluid channels. The Both fluids to be mixed are in a variety through the fluid channels fluid lamellae separated from each other, which are oppositely parallel flowing to each other and arranged alternately to each other.

The process according to the invention for mixing at least two fluids comprises at least four process steps. In the 1st Step a plurality of separate fluid flows of the two fluids are brought together, with alternating adjacent fluid lamellae of the two fluids being formed. In the 2nd Step, the fluid lamellae thus combined are discharged to form a focused total fluid flow. In the 3rd Step the total fluid flow thus obtained is introduced as a fluid jet into a swirl chamber, forming an inward flowing fluid spiral. In the last process step, the mixture formed in this way is derived from the center of the fluid spiral.

The merging takes place in such a way that the initially separate fluid flows flow into a room. Here, the fluid flows can be parallel to each other or aligned one inside the other, for example radially inwards. When merging, fluid lamellae form, the Cross-sectional areas initially correspond to those of the fluid flows. By the Purging as a focused total fluid flow takes place in a reduction in width and or the cross-sectional area of the fluid fins instead, at the same time Increase in flow rate. The accelerated focused Total fluid flow is introduced as a fluid jet into the swirl chamber. The in the fluid jet entering the swirl chamber flows along a spiral  Line inwards to the center of the vortex chamber where the mixture is derived becomes. Due to the previous focusing, the fluid flow is accordingly narrow alternately adjacent fluid lamellae.

Only the fluid flowing in the outermost turn borders on the lateral inner surfaces of the swirl chamber; the inner turns of the Fluid spirals border on both sides to the one flowing in the same direction Fluid of the previous and subsequent turns. Therefore contributes to Friction essentially just the contact with the top and bottom Inner surface of the vortex chamber at. The one achieved with this mixer Pressure loss is therefore less than that of a mixer with a long focusing channel. In addition, is by the spiral shape is a compact design with a long mixing section and thus realized a long dwell time.

Another advantage is the contact of one turn of the fluid spiral with the previous and subsequent turns, resulting in faster diffusive mixture of the fluid lamellae contributes to each other.

Laminar inside the vortex chamber is advantageous Flow conditions. However, it is also conceivable in some areas turbulent flow conditions with a spiraling overall to have fluid flow flowing inside.

With regard to complete mixing by diffusion, the Spiral fluid flow flowing inward of sufficient length and with a sufficient number of turns to get into each A sufficient dwell time for the fluid volume flowing into the vortex chamber achieve.  

The setting of the desired ratios can be done in particular by a corresponding choice of the cross-sectional area of the incoming focused Total fluid flow, the shape and dimensions of the swirl chamber and the Cross-sectional area of the outlet for the mixture formed from the Vortex chamber can be reached.

Fluid streams each having a width in the range of 1 μm are preferred up to 1 mm and a depth in the range of 10 µm to 10 mm merged.

The combined fluid flows are preferably focused such that the Ratio of the cross-sectional area of the focused total fluid flow to that Sum of the cross-sectional areas of the fluid flows to be combined in each case perpendicular to the flow direction in the range from 1 to 1.5 to 1 to 500, preferably in the range from 1 to 2 to 1 to 50. The smaller that Ratio, the more the slat width is reduced and the stronger the flow rate is increased at which the focused total fluid flow is introduced as a fluid jet into the swirl chamber. According to one The focused total fluid flow has one over its Constant cross-section. Another one Design variant takes the cross-sectional area of the focused Total fluid flow from the area where the fluid flows converge Confluence with the vortex chamber, with the above ratio for the area with the smallest cross-sectional area applies.

The ratio of the length of the focused total fluid flow to its width is preferably in the range from 1 to 1 to 30 to 1, preferably in the range 1 , 5 to 1 to 10 to 1. Here, the focused total fluid flow should be as long as possible to ensure a sufficiently focused one Force effect while maintaining the laminar flow conditions. However, the focused total fluid flow should be made short in order to be able to introduce the total fluid flow as quickly as possible as a fluid jet into the swirl chamber with a view to a low pressure drop and a compact design.

The vortex chamber advantageously has an im in the plane of the fluid spiral substantially round or oval shape to form a fluid spiral to enable laminar flow conditions and low pressure loss.

In one embodiment, the focused total fluid flow becomes acute Introduced into the vortex chamber at an angle or preferably tangentially, in particular to generate as many turns of the fluid spiral as possible, and around dead water areas, i.e. H. Area that does not flow continuously be avoided.

When contacting immiscible fluids (e.g. liquid-gaseous), it can be favorable, the disperse phase at a steeper angle than that to let the continuous phase flow into the swirl chamber. By a neighboring tangential inflow of the continuous phase can resulting drops or bubbles are sheared off, which makes smaller ones Receives drops / bubbles. Because in the case of mixing liquid and gaseous Fluids the liquid has a much higher mass than the gas the spiral formation only by introducing the gases at a steeper angle little disturbed.

It may be advantageous to use the combined fluid flows and / or the Vortex chamber to introduce another fluid. The other fluid can one Mixture stabilizing auxiliary, for example an emulsifier, exhibit. It is also conceivable that the fluid flows already have one Additive added.  

According to a preferred embodiment, the first two Method steps in at least two spatially separate locations each performed simultaneously and the focused total fluid flows thus obtained initiated in a plane of the vortex chamber in such a way that a common inward flowing fluid spiral that consists of at least two individual fluid spirals lying in one another is formed. The developing ones Fluid spirals lie together in one plane and around a center, that the respective turns are adjacent to each other. This results in for example two or three initiated total focused fluid flows a kind of double or triple spiral.

In a further preferred embodiment, the first two Method steps in at least two spatially separate locations each carried out simultaneously and the focused thus obtained Total fluid flows in different levels of the swirl chamber supplied that superimposed fluid spirals flowing inward form.

For example, it is possible to have one or more in a first level focused total gas flows and total liquid flows alternately initiate adjacent in the vortex chamber and in the subsequent ones Levels of additional total liquid flows into the swirl chamber initiate. This can be achieved, for example, in that the height the swirl chamber is enlarged, z. B. the outlet at the bottom and the inlets are located near the ceiling of the swirl chamber so that the level Fluid movement is superimposed on a vertical movement. Instead of helical trajectories are obtained. Thereby can e.g. B. the residence and contact time of gas bubbles in or with a Liquid phase can be increased. Will be following in the further down Levels further total fluid flows introduced into the swirl chamber, so form these fewer turns until they are discharged from the vortex chamber. By  this embodiment is the extension of the fluid flow and a higher number of turns of the fluid spiral that forms greater residence time of the total fluid flows in the swirl chamber reached.

The focused total fluid flows are particularly advantageously symmetrical distributed in one or more levels around the vortex chamber initiated. The total fluid flows to be introduced can be the same fluids or also have different fluids, which then only in the common space can be contacted and mixed. The previously described Different versions can also be used for this Embodiment can be used advantageously.

In another embodiment, the total fluid flows are focused introduced into the swirl chamber at different angles. Especially This embodiment is advantageous for mixing gases with Liquids used in the swirl chamber. Here, the Total gas flows at a steeper angle than the total liquid flows in the vortex chamber is initiated, the total liquid flows also gas can have liquid dispersions. As a result, the in the Total gas flows flowing in from the vortex chamber Total liquid flows divided into small gas bubbles.

The static micromixer according to the invention for mixing at least two fluids is characterized by a swirl chamber into which the Focusing channel opens in such a way that the focused total fluid flow as Fluid jet enters, forming an inward flowing fluid spiral, and at least one fluidly connected to the swirl chamber standing outlet channel for discharging the mixture formed.  

The plurality of alternately adjacent fluid channels preferably has one Width in the range of 1 µm to 1 mm and depth in the range of 10 µm up to 10 mm for separate supply of the fluids as fluid flows.

The inlet chamber, into which the fluid channels open, serves the Merging the plurality of separate fluid flows of the two fluids. The Focusing channel is used to discharge those united in the inlet chamber Fluid flows fluidly to form a focused total fluid flow connected to the inlet chamber. The focusing channel opens in such a way the vortex chamber that the focused total fluid flow as a fluid jet occurs with the formation of a concentrically flowing inward Fluid spiral. The at least one fluidically in with the swirl chamber Connected outlet channel is used to discharge the mixture formed.

Regarding the benefits associated with this micromixer, reference is made to The above statements on the method according to the invention, in particular regarding low pressure drop, increase that for faster diffusive mixing available contact area and small design.

The rapid mixing is achieved by creating very thin fluid lamellae and thus achieved by reducing the diffusion path. The Fluid fins are fed to the swirl chamber, which is a further reduction the diffusion path by tilting the fluid lamellae and reducing the Slat width causes. The swirl chamber can be designed to be relatively large become (large diameter, high height), yet become very thin Slats produced. The pressure loss in the swirl chamber can be caused by the large hydraulic diameter can be kept low. Only that Constriction through the focusing channel contributes to pressure loss. This However, constriction can be very local, i.e. H. on a very small one Flow length, happen so that there is only a moderate pressure drop comes.  

The inlet chamber preferably has one of the fluid channels opposite, concave wall into which the focusing channel advantageously open in the middle.

Due to the concave wall, a quick merging is connected with a focusing and discharge into the focusing channel while maintaining the Fluid fins reached.

However, it is also conceivable to gradually bring the combined fluid lamellae onto the Supply focusing channel, for which purpose the inlet chamber in at least one in Flow direction level triangular-tapered or funnel-shaped is trained.

According to a further embodiment, the inlet chamber has an in Flow direction constant cross section. A focus takes place in the Then the inlet chamber does not take place, but only in the focusing channel for example a tapering cross-section in the direction of flow can have. In this case, the cross section of the Inlet opening of the focusing channel the cross section of the inlet chamber correspond.

The focusing channel can also be constant in the direction of flow Have cross-section, which is used in particular when the Inlet chamber already ensures focusing so that the Focusing is only continued in the focusing channel.

Two preferred embodiments, such as the fluid channels in the Open inlet chamber are a parallel alignment and one Alignment radially towards the inlet chamber.  

In the sense of a simple technical implementation, it is advantageous if the Fluid channels, the inlet chamber, the focusing channel and / or the Vortex chamber have the same depth. Here it is also from Advantage if the openings of the fluid channels at least in the area of Inlet chamber lie in one plane.

The focusing channel is preferably designed such that the ratio the cross-sectional area of the focusing channel to the sum of the Cross-sectional areas of the fluid channels opening into the inlet chamber each perpendicular to the channel axis in the range from 1 to 1.5 to 1 to 500, preferably in the range from 1 to 2 to 1 to 50. As a result, an im Compared to the predetermined width of the fluid channels further reduce the Slat width and / or cross-sectional area and associated therewith Increased flow rate achieved. According to a variant the focusing channel essentially has one over its entire length constant cross section.

According to another embodiment variant, the cross-sectional area of the Focusing channel from the inlet chamber to the swirl chamber, whereby above ratio of cross-sectional areas for the area with the smallest Cross-sectional area is to be applied. The cross-sectional area of the Focusing channel in the area where it opens into the swirl chamber determines with the width and thus the number of turns of the spiral convoluted fluid flow. The ratio of the width of the in is advantageous Vortex chamber opening focusing channel to the diameter of the Vortex chamber smaller in the plane in which the fluid spiral is formed or equal to 1 in 10.

The ratio of the length of the focusing channel to its is preferably Width at least in the area of the confluence with the swirl chamber from 1 to 1 to 30 to 1, preferably in the range from 1.5 to 1 to 10 to 1.  

Here, the length of the focusing channel is advantageously chosen so that a Focus on small fluid lamella widths while maintaining the fluid lamella and in the sense of a low pressure drop, a quick introduction into the Whirl chamber occurs.

In a preferred embodiment, the focusing channel is in one arranged at an acute angle or tangent to the vortex chamber. In particular, this allows the fluid lamella flow to be introduced below Maintaining laminar flow conditions and forming one Fluid spiral with a large number of turns.

The vortex chamber preferably points in a plane in which the Focus channel is an essentially round or oval Cross section on. Dead water areas are thereby avoided. Especially the vortex chamber preferably has an essentially cylindrical shape on. The height of the focusing channel is advantageous here, at least in Area of the confluence, less than or equal to the height of the swirl chamber.

The outlet channel or channels preferably open below and / or above a central area, especially in the area of the center, into the Vortex chamber. The cross-sectional area of the outlet channel or channels is advantageous compared to the diameter of the swirl chamber and Cross-sectional area of the opening focusing channel dimensioned so that a fluid spiral with a large number of turns can form. The ratio of the diameter of the outlet channel to is preferably The diameter of the vortex chamber is 1 to 5 or less.

According to a further embodiment, the Focusing channel or the vortex chamber one or more Supply channels for supplying another fluid. Such fluids can be an auxiliary stabilizing the mixture, for example one  Emulsifier. The feed channels advantageously open tangentially the vortex chamber, so that between adjacent turns of the fluid spiral in each case there is a stream of the further fluid. Mouth particularly advantageous Feeding a gaseous, further fluid into at least one Fluid-containing fluid spiral in the vortex chamber the supply channels for the other fluid is not tangential, but at a steeper angle Vortex chamber. In this way, the supplied gas from the fluid spiral divided into small gas bubbles and finely distributed.

According to a further embodiment, the plurality are adjacent Fluid channels, the inlet chamber into which the fluid channels open, and with the focusing chamber fluidly connected to the inlet chamber two or more each and the two or more Focusing channels flow into one level in one plane Vortex chamber. The focusing channels open out in such a way Angles or preferably tangentially into the swirl chamber that the Fluid jets corresponding to two or more adjacent to one another concentrically Form fluid spirals flowing inwards. The focus channels are advantageous in one plane equidistant from the common Eddy chamber arranged at the mouth. The two or more Variety of adjacent fluid channels, inlet chambers and Focusing channels are arranged and separated from each other only fluidly in with each other via the common swirl chamber Connection. These structures can supply the same fluids, for example twice the fluids A, B, or different Fluids, for example fluids A, B and C, D, are used.

In a further preferred embodiment, the plurality are adjacent Fluid channels, the inlet chamber into which the fluid channels open, and with the focusing chamber fluidly connected to the inlet chamber two or more each and the two or more  Focusing channels flow into one at several levels Vortex chamber.

In a further advantageous embodiment, the Focus channels for the total fluid flows at different angles into the vortex chamber. This embodiment is particularly for Mixing focused total gas streams with total fluid streams contain at least one liquid used in the swirl chamber. The In this case, feed channels for the total gas flows open into one more acute angle than the feed channels for the at least one liquid containing total fluid flows into the swirl chamber. In this way The total gas flows introduced in steep are of the in more acute Total liquid flows introduced into fine gas bubbles.

According to a further preferred embodiment, the Fluid guide structures as recesses and / or openings in plates from a material which is sufficiently inert for the fluids to be mixed brought in. Recesses, such as grooves or blind holes, are in one level and perpendicular to it surrounded by material. Breakthroughs like slots or holes, for example, go through the material through, d. H. are only laterally surrounded by the material in one plane. The open structures of the recesses and breakthroughs are made by Stacking with further plates to form fluid guide structures, such as fluid channels and chambers, the plate stack being fluidly tight to the outside final deck and / or floor panel inlets for the two Fluids and / or at least one discharge for the mixture formed exhibit.

In a variant of this embodiment, the structures of the fluid channels are the inlet chamber, the focusing channel and the swirl chamber as Recesses and / or openings in at least one as a mixer plate  serving plate introduced. The open structures of the mixer plate are through a cover and fluidically tightly connected to the mixer plate Base plate completed.

According to a further variant of this preferred embodiment, the static micromixers between the mixer plate and the base plate one connected to them in a fluid-tight manner Distribution plate for separately supplying the fluids from the inlets the base plate to the fluid channels of the mixer plate. The Distributor plate advantageously has a number of holes for each fluid to be supplied, each hole being assigned to exactly one fluid channel. So serve with two Fluids the first row of the supply of the first fluid and the second row the supply of the second fluid.

Suitable materials come depending on the ones used Fluids different materials, such as polymer materials, Metals, alloys, glasses, quartz glass, ceramics or semiconductor materials, like silicon, in question. Plates with a thickness of 10 μm to 5 mm are preferred, particularly preferably from 50 μm to 1 mm. Suitable procedures for For example, fluid-tight connection of the plates to one another pressing together, using seals, gluing or anodizing Bonding.

Known precision engineering and microtechnical manufacturing processes in question, such as Laser ablation, spark erosion, injection molding, stamping or galvanic Deposition. Also suitable are LIGA processes that include at least the steps structuring with high-energy radiation and galvanic deposition and possibly include impressions.  

The inventive method and the static micromixer advantageous for carrying out chemical reactions of two or more Substances used, both substances in an introduced fluid or the first substance in a first fluid and the second substance in a further fluid are included. For this purpose, static micromixers are advantageous Integrated means for controlling the chemical implementation, such as Temperature or pressure sensors, flow meters, heating elements, Indwelling tubes or heat exchangers. These funds can be used for a static Micromixers on plates with the fluid guide structures or others arranged above and / or below and functional with these Connected plates can be arranged. To be carried out heterogeneously catalyzed chemical reactions can be the material of the static Micromixer also have catalytic material.

The inventive method and the Micromixer according to the invention for producing a gas-liquid Dispersion used, wherein at least one total fluid flow introduced Gas or a gas mixture and at least one other introduced Total fluid flow a liquid, a liquid mixture, a solution, a Contains dispersion or an emulsion.

Below are embodiments of the static according to the invention Micromixer exemplified using drawings. Show it

FIG. 1a is a static micromixer, consisting of a cover plate, the mixing plate, distributor plate and base plate in each case separated from one another in a perspective view;

FIG. 1b shows a preferred mixer plate of Fig. 1a in top view,

Fig. 2 shows another preferred mixer plate in top view,

Fig. 3 shows a further preferred mixing plate in top view,

Fig. 4 shows a further preferred in plan view,

Fig. 5 is a partial section through a static micromixer according to another embodiment.

The Fig. 1a shows a static micromixer 1 with a cover plate 21, a mixer plate 20, a manifold plate 26 and a bottom plate 22 separated from each other in a perspective view.

The cover plate 21 , the mixer plate 20 , the distributor plate 26 and the base plate 22 each have a feed 23 , 23 ', 23 "for the fluid A and a feed 24 , 24 ', 24 " for the fluid B in the form of a bore. The bores are arranged such that when the plates are stacked one above the other, the feeds 23 , 23 ', 23 ", 24 , 24 ', 24 " are in fluid communication with the feed structures 23 ''', 24 ''' of the base plate 22 . The feed 23 '''for the fluid A and the feed 24 ''' for the fluid B are arranged in the form of grooves 123 a, b, 124a, b in such a way on the base plate 22 that the fluid A to the distributor structure 27 and the fluid B can be directed to the distributor structure 28 of the distributor plate 26 lying above it without substantial pressure losses. From the feed structures 23 ″ ″, 24 ″ ″, connecting grooves 123 a, 124 a lead to distributor grooves 123 b, 124 b, the connecting groove 124 b expanding in a funnel shape. The distributor plate 26 has a distributor structure 27 for the fluid A and a distributor structure 28 for the fluid B each in the form of a series of holes passing through the plate, which lie above the distributor grooves 123 b and 124 b.

The mixer plate 20 shown in plan view in FIG. 1 b has fluid channels 2 , 3 , an inlet chamber 4 , a focusing channel 5 and a swirl chamber 6 . The discharge 25 in the form of a bore in the cover plate 21 is arranged such that when the plates are stacked one above the other the discharge 25 is in fluid communication with a central region of the swirl chamber 6 of the mixer plate 20 . The channels 2 for the fluid A have a smaller length than the channels 3 for the fluid B. The channels 2 , 3 are oriented parallel to one another in their side facing away from the inlet chamber 4 , the channels 2 for the fluid A alternately lying adjacent to the channels 3 for the fluid B. In a transition region, the distance between the channels decreases in the direction of the inlet chamber 4 . In the area of the opening into the inlet chamber 4 , the channels 2 , 3 are again aligned parallel to one another. In order to achieve a uniform volume flow over all channels 2 , 3 for one fluid each, the channels 2 , 3 each have the same length among themselves. This results in that the side remote from the inlet chamber 4 ends of the fluid channels 2, 3 are each lie on an arc. The bores of the distributor structures 27 , 28 of the distributor plate 26 are also each arranged in an arc in such a way that the ends of the channels 2 , 3 are each contacted fluidically with a bore. The inlet chamber 4 , into which the fluid channels 2 , 3 open, has a concave shape in the plane of the fluid channels. In the central region of the concave wall 8 , which lies opposite the openings of the fluid channels 2 , 3 , the inlet chamber 4 merges into the focusing channel 5 . The focusing channel 5 opens tangentially into the swirl chamber 6 , which is formed by a chamber which is circular in the plane of the mixer plate 20 . The structures of the fluid channels 2 , 3 , the inlet chamber 4 , the focusing channel 5 and the swirl chamber 6 are formed through openings through the material of the mixer plate 20 , as a result of which these structures have the same depth. The underlying distribution plate 26 and the overlying cover plate 21 cover these structures, which are open on two sides, to form channels or chambers.

In the ready-to-use micromixer 1 , the plates 21 , 20 , 26 and 22 shown here separately from one another are stacked one above the other and fluidly connected to one another, as a result of which the open structures, such as grooves 23 ''', 24 ''' and openings 2 , 3 , 4 , 5 and 6 , are covered to form channels and chambers. The stack of plates 21 , 20 , 26 and 22 thus obtained can be accommodated in a mixer housing which has suitable fluid connections for the supply of two fluids and the discharge of the fluid mixture. In addition, the housing can be used to apply a contact pressure to the plate stack for fluid-tight connection. It is also conceivable to operate the plate stack as a micro-mixer 1 without a housing, for which purpose fluidic connections, for example hose nozzles, are advantageously connected to the inlets 23 , 24 and the outlet 25 of the cover plate 21 .

During the actual mixing process, a fluid A and a fluid B are introduced into the feed bore 23 and into the feed bore 24 of the cover plate 21 . These fluids each flow through the feed structures 23 ', 23 ", 23 ''' and 24 ', 24 ", 24 ''' of the plates 20 , 26 and 22 and from there are uniformly in each case into the distributor structures 27 and 28 designed as bores distributed. The fluid A flows from the bores of the distributor structure 27 into the channels 2 of the mixer plate 20 arranged exactly above it. Likewise, the fluid B passes from the bores of the distributor structure 28 into the channels 3 arranged exactly above it. The fluid flows A, B, which are conducted separately in the fluid channels 2 , 3 , are brought together in the inlet chamber 4 to form alternately adjacent fluid lamellae of the sequence ABAB. Due to the semi-concave shape of the inlet chamber 4 , the combined fluid flows are quickly transferred into the focusing channel 5 . The focused total fluid flow thus formed is introduced tangentially into the swirl chamber 6 as a fluid jet. A fluid spiral 100 flowing concentrically inwards is formed in the swirl chamber 6 . The mixture of fluids A, B formed is discharged through the discharge bore 25 of the cover plate 21 located above the center of the swirl chamber 6 .

FIG. 2 shows a mixer plate 20 with three focusing channels 5 , 15 , 35 opening into a common swirl chamber 16 in a top view. The focusing channels 5 , 15 , 35 are each in fluid communication with an inlet chamber 4 , 14 , 34 into which the alternatingly adjacent fluid channels 2 , 3 ; 12 , 13 ; 32 , 33 merge. For the sake of clarity, the fluid channels 2 , 3 ; 12 , 13 ; 32 , 33 compared to the arrangement in Fig. 1b shown in simplified form. In contrast to the mixer plate 20 according to FIG. 1b, the inlet chambers 4 , 14 , 34 in the plane of the mixer plate 20 are funnel-shaped from the openings of the fluid channels 2 , 3 ; 12 , 13 ; 32 , 33 formed tapering to the focusing channel 5 , 15 , 35 . The focusing channels 5 , 15 , 35 themselves narrow in width up to the point where they join the common swirl chamber 16 . The arrangements of the fluid channels 2 , 3 ; 12 , 13 ; 32 , 33 , from inlet chambers 4 , 14 , 34 and focusing channels 5 , 15 , 35 are arranged equidistantly on the circumference of the common vortex chamber 16, which is circular in the plane shown, such that the focusing channels 5 , 15 , 35 open tangentially into them. An outlet channel 7 is arranged in the cover plate located above the mixing plate 20 and above the center of the common swirl chamber, the position of which is indicated here by a dashed circular line. The separate supply of the fluids into the fluid channels takes place through a base and distributor plate analogous to the arrangement shown in FIG. 1a. The feeds can be designed in such a way that the fluid channels 2 , 12 , 32 for one fluid and the fluid channels 3 , 13 , 33 for the other fluid are each supplied with the same fluid, so that the static micromixer can be used to mix two fluids. However, it is also conceivable to design the feeds in such a way that three or more fluids can be mixed with the micromixer. A wide variety of feeding options are available here. The formation of fluid lamellae of the sequence ABACAB in the common swirl chamber 16 is explained here as an example.

Fig. 3 shows in plan view a mixing plate 20 with a swirl chamber 16 into which two focusing channels 5, 15 and two supply ducts 9 a, 9 b open out. The focusing channels 5 , 15 are each in fluid communication with an inlet chamber 4 , 14 into which the alternately adjacent fluid channels 2 , 3 ; 12 , 13 merge. For the sake of clarity, the fluid channels 2 , 3 ; 12 , 13 compared to the arrangement in Fig. 1b shown in simplified form. In contrast to the mixer plate 20 according to FIG. 1b, the inlet chambers 4 , 14 are funnel-shaped in the plane of the mixer plate 20 from the openings of the fluid channels 2 , 3 ; 12 , 13 designed tapering to the focusing channel 5 , 15 . The focusing channels 5 , 15 themselves narrow in width up to the point where they enter the common swirl chamber 16 . The arrangements of the fluid channels 2 , 3 ; 12 , 13 , from inlet chambers 4 , 14 focusing channels 5 , 15 and feed channels 9 a, 9 b are arranged equidistantly on the circumference of the circular vortex chamber 16, which is circular in the plane shown, such that the focusing channels 5 , 15 and the feed channels 9 a, 9 b open alternately tangentially into these. An outlet channel 7 is arranged in the cover plate located above the mixing plate 20 and above the center of the common swirl chamber, the position of which is indicated here by a dashed circular line. The separate supply of the fluids into the fluid channels and the supply channels 9 a, 9 b takes place through a base and distributor plate analogous to the arrangement shown in FIG. 1a. The feeds can be designed so that the fluid channels 2 , 12 a first fluid, the fluid channels 3 , 13 a second fluid and the feed channels 9 a, 9 b, a third fluid, for example an auxiliary, is supplied so that the static micromixer for Mixing two fluids with the simultaneous addition of an auxiliary stabilizing the mixture can be used. In this exemplary embodiment, too, it is conceivable to design the feeds in such a way that three or more fluids can be mixed with the micromixer with the simultaneous addition of an auxiliary agent which stabilizes the mixture. A wide variety of feeding options are available here. As an example, the formation of fluid lamellae of the sequence ABACAD in the common swirl chamber 16 is explained here.

FIG. 4 shows a mixer plate 20 for producing gas-liquid dispersions with four focusing channels 5 , 15 , 35 , 45 opening into a common swirl chamber 16 in a top view. In contrast to the mixer plate 20 according to FIG. 2, two focusing channels 15 , 45 for the introduction of liquids or liquid mixtures open approximately tangentially and two further focusing channels 5 , 35 for the introduction of gases or gas mixtures into the swirl chamber 6 at a steeper angle. The focusing channels 5 , 15 , 35 , 45 are each in fluid communication with an inlet chamber 4 , 14 , 34 , 44 , into which the alternately adjacent fluid channels 2 , 3 , 32 , 33 , 42 , 43 , 52 , 53 open. For the sake of clarity, the fluid channels 2 , 3 , 32 , 33 , 42 , 43 , 52 , 53 are also shown in simplified form in this figure compared to the arrangement in FIG. 1b.

. The Figure 5 shows a partial section through a static micromixer 1, which has a cylindrical vortex chamber 116, in which a plurality of focusing channels 105, 105 '- 105' '', 115, 115 '- 115' '', 135, 135- 135 '''essentially tangential in several planes. For this purpose, several mixer plates 120 , 121 , 122 are stacked one above the other with spacer plates 125 interposed.

Different total fluid flows are fed into the swirl chamber 116 alternately via the focusing channels of one level or alternately via the focusing channels of different levels. In order to support the formation of spiral flow patterns, the fluid flows are introduced into the swirl chamber 116 approximately tangentially. The combined fluid flows from the inlet chambers into the focusing channels are supplied through vertical bores through the mixer and spacer plates 120 , 121 , 122 and 125 . The holes penetrate a defined number of mixing and spacing plates and thus establish the fluidic connection to a specific level of focusing channels. The discharge of the fluid flows from the swirl chamber takes place via a central outlet on the lower end face of the swirl chamber. As a result, a velocity component is superimposed on the flow along the cylinder axis and helical rather than spiral streamlines are formed.

embodiment

The static micromixer shown in FIGS. 1a and 1b was realized by means of microstructured glass plates. The mixer plate 20 and the distributor plate 26 each had a thickness of 150 μm and the final base plate 22 and cover plate 21 each had a thickness of 1 mm. Bores with a diameter of 1.6 mm were selected as feeders 23 , 23 ', 23 ", 24 , 24 ', 24 " in the cover plate 21 , the mixer plate 20 and the distributor plate 26 . The distributor plate 26 had two rows of 15 elongated holes each with a length of 0.6 mm and a width of 0.2 mm as distributor structures 27 , 28 . The fluid channels 2 , 3 of the mixer plate 20 had a width of 60 μm with a length of 11.3 mm and a length of 7.3 mm. In the area of the opening of the channels 2 , 3 into the inlet chamber 4, the webs located between the channels 2 , 3 had a width of 50 μm. The width of the inlet chamber 4 in the region of the mouth of the fluid channels 2 , 3 was reduced from 4.3 mm to the opposite side to a width of the focusing channel of 0.5 mm. Since all structures of the mixer plate 20 have been realized as openings, the fluid channels 2 , 3 , the inlet chamber 4 , the focusing channel 5 and the swirl chamber 6 have a depth which is equal to the thickness of the mixer plate of 150 μm. The length of the inlet chamber 4 , ie the distance between the confluence of the fluid channels 2 , 3 and the confluence of the focusing channel 5 , was only 2.5 mm in order to enable the combined fluid streams to be quickly derived and focused. The ratio of the cross-sectional area of the focusing channel to the sum of the cross-sectional areas of the fludica channels 2 , 3 was thus 1 to 3.6. With a length of 2.5 mm of the focusing channel 5 , a ratio of length to width of 5 to 1 was achieved. The focusing channel 5 merged longitudinally into the channel-like swirl chamber 6 with a length of 24.6 mm and a width of 2.8 mm. The opening angle of the side surfaces of the swirl chambers 6 in the transition area between the swirl chamber 6 and the focusing channel 5 was 126.7 °. The four plates shown in FIG. 1a had an outer dimension of 26 × 76 mm. The plates were structured photolithographically using photostructurable glass using a method as described in Microelectronic Engineering 30 ( 1996 ), pp. 497-504. The plates were fluidly sealed together by anodic bonding.

LIST OF REFERENCE NUMBERS

1

Static micromixer

2

Fluid channel for fluid a

3

Fluid channel for fluid b

4

inlet chamber

5

focusing channel

6

swirl chamber

7

exhaust port

8th

Concave wall

9

a,

9

b feed channel

12

Fluid channel for fluid a

13

Fluid channel for fluid b

14

inlet chamber

15

focusing channel

16

swirl chamber

20

mixer plate

21

cover plate

22

baseplate

23

Fluid supply a

24

Fluid supply b

25

removal

26

distribution plate

27

Distribution structure for fluid a

28

Distribution structure for fluid b

32

Fluid channel for fluid a

33

Fluid channel for fluid b

34

inlet chamber

35

focusing channel

42

Fluid channel for fluid c

43

Fluid channel for fluid d

44

inlet chamber

45

focusing channel

52

Fluid channel for fluid c

53

Fluid channel for fluid d

55

focusing channel

100

fluid spiral

105

.

105

'' Focusing channel

115

.

115

'' Focusing channel

116

swirl chamber

120

mixer plate

121

mixer plate

122

mixer plate

123

groove
123a, b connecting groove

123

a distributor groove

123

b Distribution groove

124

groove

124

a connecting groove

125

spacer plate

135

.

135

'' Focusing channel

Claims (32)

1. A method for mixing at least two fluids, comprising the following steps:

• Bringing together a plurality of separate fluid flows of the two fluids to form alternately adjacent fluid lamellae of the two fluids,
• Removal of the combined fluid lamellae with formation of a focused total fluid flow,
• Introducing the focused total fluid flow as a fluid jet into a swirl chamber, forming an inward flowing fluid spiral,
• - Deriving the mixture formed from the center of the fluid spiral.

2. The method according to claim 1, characterized in that fluid flows of the two fluids, each with a width in the range from 1 µm to 1 mm and a depth in the range of 10 µm to 10 mm with formation be brought together by fluid lamellae. 3. The method according to claim 1 or 2, characterized in that the united fluid lamellae are focused so that the ratio the cross-sectional area of the focused total fluid flow to the Sum of the cross-sectional areas of the merged Fluid lamellae each perpendicular to the flow direction in the range of 1: 1.5 to 1: 500, preferably in the range from 1: 2 to 1:50.   4. The method according to any one of claims 1 to 3, characterized characterized in that the ratio of the length of the focused Total fluid flow across its width in the range of 1: 1 to 30: 1, preferably in the range from 1.5: 1 to 10: 1. 5. The method according to any one of the preceding claims, characterized in that the focused total fluid flow is introduced into a swirl chamber ( 6 ) which has a substantially round or oval shape in the plane of the fluid spiral being formed. 6. The method according to any one of the preceding claims, characterized in that the focused total fluid flow is introduced at an acute angle or preferably tangentially into the swirl chamber ( 6 ). 7. The method according to any one of the preceding claims, characterized in that in the combined fluid lamellae or in the focused total fluid flow or in the swirl chamber ( 6 ) a further fluid, for example a fluid having a mixture stabilizing auxiliary, is introduced. 8. The method according to any one of the preceding claims, characterized records that the first two process steps on at least two spatially separate locations are carried out simultaneously and the focused total fluid flows thus obtained into a plane of Vertebral chamber are initiated such that there is a common inward flowing fluid spiral that consists of at least two individual fluid spirals lying one inside the other is formed.   9. The method according to any one of claims 1 to 7, characterized in net that the first two process steps on at least two rooms Lich separate locations are carried out simultaneously and the thus obtained total focused fluid flows in different Levels of the vortex chamber are fed in such a way that they match form other inward flowing fluid spirals. 10. The method according to any one of claims 8 or 9, characterized characterized in that carried out two or more times in the two Process steps used the same and / or different fluids become. 11. The method according to any one of claims 8 to 10, characterized in that the same and / or different total fluid flows are introduced at different angles into the swirl chamber ( 6 , 16 ) in the two process steps carried out two or more times. 12. Static micromixer ( 1 ) for mixing at least two fluids with
a multiplicity of alternately adjacent fluid channels ( 2 , 3 , 12 , 13 , 32 , 33 , 42 , 43 , 52 , 53 ) for the separate supply of the fluids as fluid lamellae,
at least one inlet chamber ( 4 , 34 , 44 ) into which the fluid channels ( 2 , 3 , 12 , 13 , 32 , 33 , 42 , 43 , 52 , 53 ) open, and
a focusing channel ( 5 , 15 , 35 , 45 , 105 , 105 ', 115 , 115 '), which is in fluid communication with the inlet chamber ( 4 , 34 , 44 ) for removing the in the inlet chamber ( 4 , 14 , 34 , 44 ) combined fluid lamellae with formation of a focused total fluid flow,
marked by
a swirl chamber ( 6 , 16 , 116 ) into which the focusing channel ( 5 , 15 , 35 , 45 , 105 , 105 ', 115 , 115 ') opens in such a way that the focused total fluid flow enters as a fluid jet, forming an inward flowing fluid spiral ( 100 ), and
at least one outlet channel ( 7 ) fluidly connected to the swirl chamber ( 6 , 16 , 116 ) for discharging the mixture formed. 13. Micromixer according to claim 12, characterized in that the adjacent fluid channels ( 2 , 3 , 12 , 13 , 32 , 33 , 42 , 43 , 52 , 53 ) have a width in the range from 1 µm to 1 mm and a depth in the range have from 10 µm to 10 mm. 14. Static micromixer according to claim 12 or 13, characterized in that the inlet chamber ( 4 , 14 , 34 , 44 ) has a concave wall ( 8 ) opposite the fluid channels, into which the focusing channel ( 5 , 15 , 35 , 45 , 105 , 105 ', 115 , 115 ') opens in the middle. 15. Micromixer according to claim 12 or 13, characterized in that the inlet chamber ( 4 , 14 , 34 , 44 ) has a constant cross section in the flow direction. 16. Micromixer according to one of claims 12 to 15, characterized in that the focusing channel ( 5 , 15 , 35 , 45 , 105 , 105 ', 115 , 115 ') has a constant or tapering cross section in the flow direction. 17. Static micromixer according to one of claims 12 to 16, characterized in that the ratio of the cross-sectional area of the focusing channel ( 5 , 15 , 35 , 45 , 105 , 105 ', 115 , 115 ') at least in the region of the confluence with the vortex chamber ( 6 , 16 , 116 ) to the sum of the cross-sectional areas of the fluid channels ( 2 , 3 , 12 , 13 , 32 , 33 , 42 , 43 , 52 , 53 ) opening into the inlet chamber ( 4 , 14 , 34 , 44 ) each perpendicular to the Channel axis is in the range from 1: 1.5 to 1: 500, preferably in the range from 1: 2 to 1:50. 18. Static micromixer according to one of claims 12 to 17, characterized in that the ratio of the length of the focusing channel ( 5 , 15 , 35 , 45 , 105 , 105 ', 115 , 115 ') to its width at least in the region of the confluence the width of the vortex chamber ( 6 , 16 , 116 ) is in the range from 1: 1 to 30: 1, preferably in the range from 1.5: 1 to 10: 1. 19. Static micromixer according to one of claims 12 to 18, characterized in that the swirl chamber ( 6 , 16 , 116 ) in a plane in which the focusing channel ( 5 , 15 , 35 , 45 , 105 , 105 ', 115 , 115 '), has a substantially round or oval cross-section. 20. Static micromixer according to one of claims 12 to 19, characterized in that the swirl chamber ( 6 , 16 , 116 ) has a substantially cylindrical shape. 21. Micromixer according to claim 20, characterized in that the pressure gauge of the swirl chamber ( 6 , 16 , 116 ) is 2 mm to 20 cm, preferably 5 mm to 10 cm. 22. Static micromixer according to one of claims 12 to 21, characterized in that below and / or above a central region of the swirl chamber ( 6 , 16 , 116 ) one or more outlet channels ( 7 ) open out. 23. Static micromixer according to one of claims 12 to 22, characterized in that the fluid channels ( 2 , 3 , 12 , 13 , 32 , 33 , 42 , 43 , 52 , 53 ), the inlet chamber ( 4 , 14 , 34 , 44 ), the focusing channel ( 5 , 15 , 35 , 45 , 105 , 105 ', 115 , 115 ') and the swirl chamber ( 6 , 16 , 116 ) are arranged in one plane and have the same depth. 24. Static micromixer according to one of claims 12 to 23, characterized in that in the inlet chamber ( 4 , 14 , 34 , 44 ), the focusing channel ( 5 , 15 , 35 , 45 , 105 , 105 ', 115 , 115 ') or the swirl chamber ( 6 , 16 , 116 ) opens into one or more feed channels ( 9 a, 9 b) for supplying a further fluid, for example a fluid having an auxiliary substance stabilizing the mixture. 25. Static micromixer according to one of claims 12 to 24, characterized in that the focusing channel ( 5 , 15 , 35 , 45 , 105 , 105 ', 115 , 115 ') at an acute angle or preferably tangentially into the swirl chamber ( 6 , 16 , 116 ) is arranged at the mouth. 26. Static micromixer according to one of claims 12 to 25, characterized in that the plurality of adjacent fluid channels ( 2 , 3 , 12 , 13 , 32 , 33 , 42 , 43 , 52 , 53 ), the inlet chamber ( 4 , 14 , 34 , 44 ) into which the fluid channels ( 2 , 3 , 12 , 13 , 32 , 33 , 42 , 43 , 52 , 53 ) open, and the focusing channel which is in fluid communication with the inlet chamber ( 4 , 14 , 34 , 44 ) ( 5 , 15 , 35 , 45 , 105 , 105 ', 115 , 115 ') are each present two or more times and the two or more focusing channels ( 5 , 15 , 35 , 45 , 105 , 105 ', 115 , 115 ' ) in a plane into which a common vortex chamber ( 6 , 16 , 116 ) opens. 27. Static micromixer according to claims 12 to 26, characterized in that the plurality of adjacent fluid channels ( 2 , 3 , 12 , 13 , 32 , 33 , 42 , 43 , 52 , 53 ), the inlet chamber ( 4 , 14 , 34 , 44 ) into which the fluid channels ( 2 , 3 , 12 , 13 , 32 , 33 , 42 , 43 , 52 , 53 ) open, and the focusing channel ( 4 , 14 , 34 , 44 ) which is in fluid communication with the inlet chamber ( 4 , 14 , 34 , 44 ) 5 , 15 , 35 , 45 , 105 , 105 ', 115 , 115 ') are each present two or more times and the two or more focusing channels ( 5 , 15 , 35 , 45 , 105 , 105 ', 115 , 115 ') open into several levels into a common vortex chamber ( 6 , 16 , 116 ). 28. Static micromixer according to claim 26 or 28, characterized in that the two or more focusing channels ( 5 , 15 , 35 , 45 , 105 , 105 ', 115 , 115 ') at different angles in the swirl chamber ( 6 , 16 , 116 ) flow into. 29. Static micromixer according to one of claims 12 to 28, characterized in that the fluid guide structures, such as the fluid channels ( 2 , 3 , 12 , 13 , 32 , 33 , 42 , 43 , 52 , 53 ), the inlet chambers ( 4 , 14 , 34 , 44 ), the focusing channels ( 5 , 15 , 35 , 45 , 105 , 105 ', 115 , 115 '), feeders ( 23 , 23 ', 23 ", 23 ''', 24 , 24 ', 24 " , 24 ''') and the swirl chambers ( 6 , 16 , 116 ), as recesses and / or openings in plates made of a material which is sufficiently inert for the fluids to be mixed, and these open structures by the stacking of the plates and by at least one have been completed with the stack of plates fluidically tightly associated top and / or bottom plate (21, 22), wherein the top and / or bottom plate (21, 22) at least one feed (23, 23 ''', 24, 24' '' ) for the two fluids and / or at least one discharge ( 25 ) for the mixture formed. 30. Static micromixer according to claim 29, characterized by an between a mixer plate ( 20 ) with fluid channels ( 2 , 3 , 12 , 13 , 32 , 33 , 42 , 43 , 52 , 53 ), inlet chamber ( 4 , 14 , 34 , 44 ), Focusing channels ( 5 , 15 , 35 , 45 , 105 , 105 ', 115 , 115 ') and vortex chamber ( 6 , 16 , 116 ) and the base plate ( 22 ) arranged and fluidly connected to this with the distributor plate ( 26 ) Feeders ( 23 ", 24 ") for separately feeding the fluids from the feeders ( 23 ''', 24 ''') in the base plate ( 22 ) into the fluid channels ( 2 , 3 , 12 , 13 , 32 , 33 , 42 , 43 , 52 , 53 ) in the mixer plate ( 20 ). 31. Use of the method and / or the static micromixer according to one or more of the preceding claims for reacting at least two substances, both substances being introduced in one Fluid or a first substance in a first fluid and a second substance are contained in another introduced fluid. 32. Use of the method and / or the static micromixer according to one or more of the preceding claims for the production a gas-liquid dispersion, wherein at least one introduced fluid a gas or a gas mixture and at least one other introduced Fluid a liquid, a liquid mixture, a solution, a Has dispersion or an emulsion.