Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F25/00—Flow mixers; Mixers for falling materials, e.g. solid particles
  • B01F25/40—Static mixers
  • B01F25/42—Static mixers in which the mixing is affected by moving the components jointly in changing directions, e.g. in tubes provided with baffles or obstructions
  • B01F25/421—Static mixers in which the mixing is affected by moving the components jointly in changing directions, e.g. in tubes provided with baffles or obstructions by moving the components in a convoluted or labyrinthine path
  • B01F25/423—Static mixers in which the mixing is affected by moving the components jointly in changing directions, e.g. in tubes provided with baffles or obstructions by moving the components in a convoluted or labyrinthine path by means of elements placed in the receptacle for moving or guiding the components
  • B01F25/4231—Static mixers in which the mixing is affected by moving the components jointly in changing directions, e.g. in tubes provided with baffles or obstructions by moving the components in a convoluted or labyrinthine path by means of elements placed in the receptacle for moving or guiding the components using baffles
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F28—HEAT EXCHANGE IN GENERAL
  • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
  • F28D7/00—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall
  • F28D7/16—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits being arranged in parallel spaced relation
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F25/00—Flow mixers; Mixers for falling materials, e.g. solid particles
  • B01F25/40—Static mixers
  • B01F25/42—Static mixers in which the mixing is affected by moving the components jointly in changing directions, e.g. in tubes provided with baffles or obstructions
  • B01F25/43—Mixing tubes, e.g. wherein the material is moved in a radial or partly reversed direction
  • B01F25/431—Straight mixing tubes with baffles or obstructions that do not cause substantial pressure drop; Baffles therefor
  • B01F25/4316—Straight mixing tubes with baffles or obstructions that do not cause substantial pressure drop; Baffles therefor the baffles being flat pieces of material, e.g. intermeshing, fixed to the wall or fixed on a central rod
  • B01F25/43161—Straight mixing tubes with baffles or obstructions that do not cause substantial pressure drop; Baffles therefor the baffles being flat pieces of material, e.g. intermeshing, fixed to the wall or fixed on a central rod composed of consecutive sections of flat pieces of material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F35/00—Accessories for mixers; Auxiliary operations or auxiliary devices; Parts or details of general application
  • B01F35/90—Heating or cooling systems
  • B01F35/93—Heating or cooling systems arranged inside the receptacle
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F28—HEAT EXCHANGE IN GENERAL
  • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
  • F28F1/00—Tubular elements; Assemblies of tubular elements
  • F28F1/10—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses
  • F28F1/12—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element
  • F28F1/38—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element and being staggered to form tortuous fluid passages
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F28—HEAT EXCHANGE IN GENERAL
  • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
  • F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
  • F28F9/007—Auxiliary supports for elements
  • F28F9/013—Auxiliary supports for elements for tubes or tube-assemblies
  • F28F9/0132—Auxiliary supports for elements for tubes or tube-assemblies formed by slats, tie-rods, articulated or expandable rods
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F28—HEAT EXCHANGE IN GENERAL
  • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
  • F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
  • F28F9/22—Arrangements for directing heat-exchange media into successive compartments, e.g. arrangements of guide plates
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F28—HEAT EXCHANGE IN GENERAL
  • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
  • F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
  • F28F9/24—Arrangements for promoting turbulent flow of heat-exchange media, e.g. by plates
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F25/00—Flow mixers; Mixers for falling materials, e.g. solid particles
  • B01F2025/91—Direction of flow or arrangement of feed and discharge openings
  • B01F2025/916—Turbulent flow, i.e. every point of the flow moves in a random direction and intermixes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F25/00—Flow mixers; Mixers for falling materials, e.g. solid particles
  • B01F2025/91—Direction of flow or arrangement of feed and discharge openings
  • B01F2025/917—Laminar or parallel flow, i.e. every point of the flow moves in layers which do not intermix
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F28—HEAT EXCHANGE IN GENERAL
  • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
  • F28D21/00—Heat-exchange apparatus not covered by any of the groups F28D1/00 - F28D20/00
  • F28D2021/0019—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for
  • F28D2021/0052—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for for mixers
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F28—HEAT EXCHANGE IN GENERAL
  • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
  • F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
  • F28F9/22—Arrangements for directing heat-exchange media into successive compartments, e.g. arrangements of guide plates
  • F28F2009/222—Particular guide plates, baffles or deflectors, e.g. having particular orientation relative to an elongated casing or conduit
  • F28F2009/228—Oblique partitions

Definitions

• the invention relates to a device for supplying or dissipating heat, for carrying out reactions and for mixing and dispersing flowing media in a housing with internals according to the preamble of claim 1.
• the device consists of a bundle of tubes or other elongated elements preferably aligned parallel to the longitudinal axis of the housing and between the tubes or the elongate elements inserted webs or web layers of a first arrangement which are inclined towards the longitudinal axis of the housing and at least a second arrangement of web layers, the angle of inclination of the webs of the first arrangement having an opposite sign like the arrangement of the second web layers and cross but do not touch.
• the bars are installed between the tubes of the tube bundle and do not touch.
• a tube or a row of tubes preferably lies between the crossing webs of the first and the second arrangement.
• the flowing medium (product) flows in the axial main flow direction around the tubes in the housing.
• the flowing medium is forced to cross-flow around the tubes and at the same time is continuously cross-mixed by the crosswise arranged webs which are inclined towards the tubes or towards the axis of the housing.
• a heat transfer medium can, but does not have to, flow in the tubes in cocurrent or countercurrent to the product.
• a round tube or the jacket space of a tube bundle heat exchanger preferably serves as the housing.
• the device according to the invention is preferably suitable for laminar flowing media, but can also be used with turbulent flow.
• the invention further relates to a method for carrying out heterogeneous, catalytic reactions or for mass transfer in a flowing medium in a device according to the invention.
• the mixing elements consist of groups of 6-10 intersecting webs based on the projection of the cross-section are arranged in intersecting planes.
• the webs or planes are inclined by preferably 45° to the direction of flow and the adjacent webs touch at the crossing points.
• the mixing elements have a length of 0.75 to 1.5D and successive mixing elements are turned by 90° and built into the housing.
• a is the heat transfer coefficient on the product side
• D (or d) is the pipe diameter
• X is the thermal conductivity of the product.
• the Nu number is also independent of the pipe length in laminar flow because of the constant cross-mixing and renewal of the boundary layer. With laminar flow, the heat transfer coefficient a is increased by a factor of 5 - 10 compared to the empty pipe.
• Usual heat transfer coefficients k for highly viscous substances with these devices are in the range of 150-250 W/(m 2 K).
• Static mixers with an X structure have the narrowest residence time spectrum of all known static mixers.
• the measured Bodenstein number Bo is 50-100 m' 1 or, for example, up to 200 in a reactor 2 m long (F. Streiff in Heat transfer in plastics processing, pp. 241/275, VDI Verlag, Düsseldorf 1986). This practically achieves an ideal plug flow
• the Bodenstein number is a common, dimensionless measure for the width of the residence time distribution or the axial backmixing according to the dispersion model
• the flowing medium is also 2-phase (gas/liquid) and the device should also bring about an intensive mixing of the phases and dispersion in addition to the heat exchange. Examples are the heating of polymer solutions with volatile components or the cooling of plastic melts with blowing agents.
• An X-mixer in a housing that is heated or cooled from the outside is the ideal solution for all of these tasks with low throughputs.
• scale-up becomes impossible at industrial throughputs because the surface-to-volume ratio in a pipe with a larger diameter decreases very rapidly and the heat can no longer be transferred sufficiently.
• a possible solution to this problem is to connect many tubes in parallel in a tube bundle heat exchanger and to install mixing elements in the tubes. As a result, the favorable properties of the mixers are retained, but unfortunately only in one tube. There can be very large differences in throughput and residence time from tube to tube. This risk is particularly high when viscous products are to be cooled or when polymer solutions react simultaneously in the heat exchanger and/or at least partially degas. Different temperatures and viscosities in the individual pipes result in so-called maldistribution. The maldistribution leads to a glaring inequality of flow velocity, temperature and viscosity in the individual tubes. The result can be equipment failure or reduced product quality.
• the tube bundle heat exchange apparatus must be built with short and many tubes. This makes them very expensive, in addition to the cost of the mounting elements, because the tube sheets become thick and the volume of the heads becomes very large.
• the pressure drop in the mixing elements prevents premature partial degassing and the product is damaged as a result or complete degassing is impeded.
• Another disadvantage of the X structure is its mechanical weakness in absorbing the flow forces. Particularly when subjected to tension, they behave like a scissor lattice and are easily pulled apart. But even under pressure, they behave like a spring and are not very stable. As a result, the bars have to be built very thick for high-viscosity products. This leads to a further sharp increase in pressure loss. An attempt is made to make the structure more stable by means of reinforcement elements or external rings.
• Patent specification DE 28 39 564 proposes a static mixer heat exchanger or reactor which adopts the basic idea of the X-structure but replaces the webs with tubes in which a heating or cooling medium flows.
• a solution was found to make the specific heat exchange area per volume comparable with scale-up as with a with a small housing diameter and at the same time to obtain a similar mixing effect and a similar residence time behavior as with an X-mixer.
• the structure is made up of intersecting, meandering, curved pipe coils.
• the tubes are also preferably inclined at 45° to the direction of flow and assume the function of the webs. A number of such intersecting snakes each form a mixing element and successive elements are installed in a housing rotated by 90°.
• Each element must be equipped with its own collector for the heat transfer medium.
• the design and construction of these devices is very demanding and expensive.
• the element length is selected as long as possible, which of course has an unfavorable effect on the mixing effect due to the small number of 90° rotations.
• the pressure loss on the product side as well as on the heat transfer medium side is very high.
• the flow rate in the individual pipe coils can be very uneven. The problem is particularly acute when, for practical reasons, the case is circular instead of square as originally thought. This leads to the risk of additional maldistribution on the product side.
• the residence time distribution is as narrow as in the X-mixer.
• Measured Bodenstein numbers are also around 60m' 1 .
• the homogenization length for laminar mixing is up to twice as long as with the SMX mixer because of the round shape of the bars and because of the long elements (W. Müller, Chem.-Ing.Tech. 54 1982, No. 6).
• the structure cannot be used for high-viscosity products without additional support elements because it is not sufficiently stable.
• the stability is improved with additional elongated support elements, but it remains a weak point and is expensive.
• the devices have proven themselves and are known as SMR reactors and are often used as polymerization reactors or coolers for viscous products, for example in fiber plants or for cooling plastic melts.
• Patent specification EP 1 067 352 proposes another static mixer heat exchanger or reactor with crossing webs of the X structure with an integrated tube bundle.
• the X-structure has only 4 webs based on the projection of the cross-section and the tubes are guided through holes in the webs inclined at 45° to the direction of flow.
• the ridges lie in intersecting groups of planes which enclose an angle of 90° with one another.
• the webs touch and are connected to each other and at least partially to the tubes.
• the X-structure of 4 webs across the cross-section is built up first and the tubes are fed through the holes in the webs of the finished structure.
• the axial web distance should be 0.2 - 0.4 D.
• the object of the invention is a device for supplying and removing heat, for carrying out reactions or as a reactor for photosynthesis and for mixing and dispersing flowing, liquid, gaseous or multi-phase media in a tubular housing without maldistribution and with a to create a narrow residence time distribution, preferably for viscous products, with an X-structure, which is much easier and cheaper to produce than previously known devices with this structure and, if necessary, also have high stability against the flow forces and a lower pressure loss, both on the heat transfer medium - as exhibited on the product page.
• the object is solved by the features of claim 1. Particularly advantageous embodiments are the subject matter of the dependent patent claims.
• Another aspect of the present invention is the subject of independent method claim 20.
• the "pitch t" or the “tube pitch t” refers in particular to the distance between the center points of two adjacent tubes in a row of tubes transverse to the tube or housing axis or the distance between the centers of two adjacent elongate elements in a row understood transversely to the axis of the elongate elements or housing axis.
• Quadratic division means in particular that the distances from adjacent tube centers are equal in a first direction transverse to the tube or housing axis and in a second direction transverse to the tube or housing axis, the second direction being perpendicular to the first direction.
• This quadratic division is shown and described, for example, in the VDI heat atlas, 6th edition, 1991, Section Ob6, Figure 9.
• FIG. 1 shows a side view of a part of an embodiment variant of a device according to the invention with 9 tubes and with 4 crossing webs in relation to the projection of the cross section in a cut open housing
• FIG. 2 shows a projection in the direction of flow of a cross section through an embodiment variant of a device according to the invention with 9 tubes and 4 layers of webs in the projection of the cross section.
• FIG. 4 shows a projection in the flow direction of a cross section through an embodiment variant of a device according to the invention with 16 tubes and 5 webs in the projection of the cross section, the width of the webs having cutouts in the area of the tubes, and the web width b being smaller than the tube division but greater than is the space between adjacent tubes. There are no pipes in the axes of the cross sections. This arrangement allows U-tube loops.
• 5 shows a projection in the direction of flow of a cross section through an embodiment variant of a device according to the invention with 32 tubes and 7 layers of webs in the projection of the cross section
• FIG. 6 shows the projection in the direction of flow of a cross section through an embodiment variant of a device according to the invention as in FIG. 5 with only partially used spaces for the pipes or elongate elements
• Fig. 7 shows a projection in the flow direction of a cross section through an embodiment of a device according to the invention with 45 tubes and 8 layers of webs in the projection of the cross section, the sign of the inclination of the webs being the same for 2 adjacent web layers (indicated by hatching) and in groups changes
• FIG. 8 shows the projection in the direction of flow of a cross section through an embodiment variant of a device according to the invention, with interwoven webs as crosses rotated by 90°
• FIG. 9 A perspective representation of an embodiment variant of a device according to the invention with webs (31a, 41b) partially cut to the length L of the mixing elements.
• the webs have a maximum width b > (t - d) and partially enclose the tubes
• FIG. 10 A perspective view of a further embodiment of a device according to the invention, in which the webs are at least partially offset from one another in the longitudinal direction and the mixing elements are axially spaced
• FIG. 11 A perspective representation of a further embodiment variant of a device according to the invention, in which the webs are woven into one another as crosses rotated by 90° according to FIG.
• FIG. 13 Perspective view of a possible grid-like connection of webs to a web layer by support rods 14
• the device consists of a preferably circular housing 1 with an inside diameter D and a built-in tube bundle with tubes 2 parallel to the longitudinal axis and to the main flow direction and having an outside diameter d.
• Other elongated elements can also take the place of the pipes.
• the tube bundle preferably has a square tube pitch t.
• the angle of inclination of the crossing webs (31, 41) preferably has an opposite sign and the webs following one another in the axial direction of a web layer between the tubes are preferably parallel to one another and preferably all have the same distance m.
• the webs of the web layers preferably lie one behind the other in the transverse direction in parallel, intersecting planes A, B with the angle of inclination ⁇ to the longitudinal axis. All webs preferably have the same angle of inclination a.
• the webs or web layers can be offset axially as desired and/or for the vertical distances m of the webs or also the angle of inclination to differ within one web layer or from one web layer to the next.
• the webs then no longer lie one behind the other in the transverse direction in common planes.
• the webs have a width b and this width is less than or at most equal to the tube pitch t.
• the webs are preferably perpendicular to the tubes with their width b.
• the webs can, but do not have to, reach all the way to the housing wall or they can also only touch it at certain points.
• a number n a of webs following one another in the axial direction form a web layer and all web layers in a cross section within the Length L form a mixed element.
• the bar layers of successive mixing elements are rotated by 90° and inserted between the tubes.
• the length L is preferably 0.5 to 4D.
• a cut to length mixing element consists of full length fins (31, 41) and cut fins (31a, 41b).
• Wider webs have recesses (Fig. 4) for the passage of the tubes and can also be easily installed in existing tube bundles if they are slightly inclined during installation.
• the contact line to the tubes is increased by wider webs. This has a beneficial effect on the strength of the structure and heat transfer when the tubes are connected to the webs.
• not all ridges of a device need to have the same width and shape.
• the webs in this variant are slightly wider than the free space between the rows of tubes and have a maximum width b > (t - d).
• the webs do not necessarily have to be cut to the length L, but the webs of the web layers can protrude into the following element as long as there is no conflict with the following webs rotated by 90° or the mixing elements can be installed at intervals, as shown in FIG. As such, frequent 90° rotation of the web orientation would be desirable for cross mixing and heat transfer to the tubes.
• the length L is too short, the transport over the entire cross-section becomes insufficient and the construction becomes more complex.
• the number of 90° turns is too small, cross-mixing is reduced.
• the device according to the invention offers a further, hitherto unknown type of web arrangement, as shown in FIGS. 8 and 11.
• the webs (31, 41) and the webs (31', 4T) rotated through 90° are inserted into one element interwoven between the tubes 2.
• the result is an element that mixes in two transverse directions at the same time. All subsequent elements have the same structure.
• the elements can be built in spaced or nested as much as possible. The typical 90° rotation of individual elements is no longer necessary and a uniform structure is created.
• All mixing elements within a device according to the invention are preferably constructed in the same way and with the same web spacing. However, for special tasks such as for locally dispersive mixing, or for locally increased heat transfer or mass transfer, it may be necessary that, for example, the axial distance m of the webs, the web width b or the Mixing element length L of individual mixing elements or groups of mixing elements within a device should be narrower or smaller.
• the webs can be connected to the tubes at all or only some of the crossing points by welding, soldering or gluing.
• the webs do not necessarily have to be connected to the tubes if this is not desired for practical reasons, and groups of webs or web layers can be connected to one another by spacers and additional supports 5.
• the webs of a layer can also be connected by metal sheets and be inclined. Then the web layers can take the form of a corrugated sheet.
• the width of the webs can be variable over their length, and the lateral boundaries can have a curved shape, as shown in FIG. 3 as a further variant.
• FIGS. 2 to 8 the different angles of inclination of the crossing webs are indicated by the different direction of the hatching.
• the terms “tubes” or “tube bundles” are used in the following, in which a medium for supplying or dissipating heat preferably flows, with other, elongate elements, also without a heat transfer medium, such as rods, being used instead if required.
• Profiles, heating rods, rod-shaped lamps or tubes with a semi-permeable or porous wall can occur.
• the applicability of the invention is not limited to metallic materials.
• the webs are preferably flat, plate-shaped profiles made of sheet metal or else U- or V-shaped profiles or tubes or hollow profiles or rods.
• the surface of the webs can also be structured. 12 shows a selection of possible profile shapes that can be used both as webs and as elongate elements.
• the manufacture of the device according to the invention for removable tube bundles is very simple.
• the webs are installed in U-tube bundles because the device can be expanded in this way and no thermal stresses can occur. In this case there are no pipes in the Main axes of the case cross-section. The disadvantage of this arrangement is that correct counterflow to the heat transfer medium is not possible.
• the entire fixtures and pipes or elongated elements are produced as a monolithic component using a 3D printer, if the dimensions and the material allow it.
• the built-in parts are made from an easily meltable material in a 3D printer and covered with a mostly ceramic mass. Then the material inside the hardened mold is melted out and what remains is a mold that is filled with liquid metal (investment casting) or a hardening resin.
• the specific exchange area (A/V) in reactors according to the invention is >50 m 2 /m 3 and can be up to 400 m 2 /m 3 .
• the specific heat transfer capacity of the reactors according to the invention with highly viscous products can reach over 100 kW/m 3 K. For example, in the case of strongly exothermic polymerization reactions, hot spots and runaway reactions occur if the specific heat transfer capacity of the reactor is not large enough.
• the specific exchange area and the specific heat transfer capacity can be selected largely independently of the reactor or apparatus volume. This makes the scale-up particularly easy. For example, polymerization reaction ions are strongly exothermic and at higher viscosities.
• the pipe division is preferably selected to be uniform over the entire cross section. With a square tube pitch, the structure is particularly simple because the components of all mixing elements are the same. It is also possible that the divisions in both transverse directions and the web widths of the groups rotated by 90° are different or deviate locally. However, it is also possible to choose the division differently locally, or to omit individual or groups of tubes, or instead of tubes for the heat exchange, in whole or in part, tubes or elongate elements with other properties such as light-emitting elements or elements with semi-permeable or porous walls or simply tubes or Use rods without a heat transfer medium or other elongated profiles to reinforce the structure at the intended tube locations if the required heat transfer capacity allows.
• FIG. 5 shows a view in the direction of flow for an embodiment variant of a device according to the invention with 32 tubes and 7 webs over the cross section.
• the flowing medium only has to be mixed or dispersed statically, without heat being supplied or removed at the same time, or the product having to be tempered. It is then possible for tube spaces to be partially vacant and/or the tubes are wholly or partially replaced by full profiles which serve as reinforcement for the structure. This creates static mixers with very high stability against the flow forces, such as those that occur during extrusion or injection molding of tough plastic melts.
• FIG. 6 shows a variant like FIG. 5, in which not all possible tube locations are occupied and in which some tubes are replaced by full rods or profiles. 12 shows a selection of possible shapes of elongate elements. The selection is not complete.
• These elongate elements can be installed both axially instead of tubes 2 and inclined thereto as alternative forms of webs (31, 41).
• Webs 31 that follow one another axially can be connected by auxiliary elements 5 to form a web layer and inserted between the tubes, as shown in FIG.
• Sheets that are inclined are also possible as a connection and the web layer becomes a corrugated sheet-like structure as shown in FIG.
• the intersecting webs or profiles which are inclined towards the housing axis, ensure intensive transverse mixing and transverse flow and improve the heat and mass transfer to the tubes.
• the vertical distance m between the webs that follow in the direction of flow is a determining measure of the pressure drop in the tube bundle structure according to the invention, because it significantly influences the wetted surfaces of the internals in the reactor.
• the distance m should therefore be as large as possible, preferably 0.2 to 0.4D, if only good cross-mixing with little or no heat exchange is required. It is expected that a more frequent crossing of the tubes with the webs and a frequent rotation of the web direction is favorable for the heat transfer to the tubes.
• the hardened mixer rods were each cut open after a length of 1 D and the maximum thickness I of a layer was measured as a measure of mixing quality and compared with the initial thickness l 0 .
• This measurement method is very simple and efficient for demonstrating the mixing process and the mixing quality in static mixers with laminar flow, especially in the Beginning of mixing.
• the result of the mixing tests is shown in FIG. 15.
• almost the same maximum layer thickness (mixing quality) is achieved in the device according to the invention with only 4 bars as in the static mixer according to the prior art with 8 bars!
• the wetted web surface of the device according to the invention is only about 60% compared to the design according to the prior art.
• the application of the device according to the invention is not only limited to the laminar flow range. It is known that the X structure is very well suited for dispersing liquids or gases in turbulent flow in low-viscosity media. This device is therefore also suitable for low-viscosity media for reactions with a high degree of heat generation or also for bioreactors. If the tubes are replaced by rod-shaped light generators or conductors also for photosynthesis. In the case of vertical installation, a catalyst carrier can also be easily filled into the housing for carrying out heterogeneous, catalytic reactions with higher heat of reaction in a fixed bed or in a fluidized bed.
• the inventive device is preferably used as a mixer-heat exchanger with high transverse and low axial back-mixing for
• a very expensive double-walled pipe is no longer required and is replaced by U-shaped pipe coils through which a heat transfer medium flows. If required, further elongated profiles at the pipe places take over the necessary reinforcement of the structure.
• the mixer according to the invention can also be heated quickly to the operating temperature, since no high stresses are to be expected in the housing, as is the case with a double-walled pipe.

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• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Chemical & Material Sciences (AREA)
• Thermal Sciences (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Dispersion Chemistry (AREA)
• Fluid Mechanics (AREA)
• Geometry (AREA)
• Physical Or Chemical Processes And Apparatus (AREA)
• Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
• Devices And Processes Conducted In The Presence Of Fluids And Solid Particles (AREA)
• Accessories For Mixers (AREA)

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• 2020
  • 2020-08-14 CH CH01018/20A patent/CH717741A2/de unknown
• 2021
  • 2021-08-11 WO PCT/CH2021/050018 patent/WO2022032401A1/de not_active Ceased
  • 2021-08-11 JP JP2023510348A patent/JP2023537141A/ja active Pending
  • 2021-08-11 MX MX2023001903A patent/MX2023001903A/es unknown
  • 2021-08-11 US US18/021,169 patent/US20230219046A1/en active Pending
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