Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F27/00—Mixers with rotary stirring devices in fixed receptacles; Kneaders
  • B01F27/80—Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a substantially vertical axis
  • B01F27/85—Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a substantially vertical axis with two or more stirrers on separate shafts
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F27/00—Mixers with rotary stirring devices in fixed receptacles; Kneaders
  • B01F27/80—Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a substantially vertical axis
  • B01F27/92—Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a substantially vertical axis with helices or screws
  • B01F27/922—Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a substantially vertical axis with helices or screws with two or more helices, e.g. with intermeshing helices
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F2215/00—Auxiliary or complementary information in relation with mixing
  • B01F2215/04—Technical information in relation with mixing
  • B01F2215/0409—Relationships between different variables defining features or parameters of the apparatus or process
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F2215/00—Auxiliary or complementary information in relation with mixing
  • B01F2215/04—Technical information in relation with mixing
  • B01F2215/0413—Numerical information
  • B01F2215/0418—Geometrical information
  • B01F2215/0422—Numerical values of angles
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
  • B01F23/40—Mixing liquids with liquids; Emulsifying
  • B01F23/47—Mixing liquids with liquids; Emulsifying involving high-viscosity liquids, e.g. asphalt
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F27/00—Mixers with rotary stirring devices in fixed receptacles; Kneaders
  • B01F27/05—Stirrers
  • B01F27/11—Stirrers characterised by the configuration of the stirrers
  • B01F27/114—Helically shaped stirrers, i.e. stirrers comprising a helically shaped band or helically shaped band sections
  • B01F27/1143—Helically shaped stirrers, i.e. stirrers comprising a helically shaped band or helically shaped band sections screw-shaped, e.g. worms
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F27/00—Mixers with rotary stirring devices in fixed receptacles; Kneaders
  • B01F27/05—Stirrers
  • B01F27/11—Stirrers characterised by the configuration of the stirrers
  • B01F27/114—Helically shaped stirrers, i.e. stirrers comprising a helically shaped band or helically shaped band sections
  • B01F27/1145—Helically shaped stirrers, i.e. stirrers comprising a helically shaped band or helically shaped band sections ribbon shaped with an open space between the helical ribbon flight and the rotating axis

Definitions

• the invention relates to a device which comprises at least one housing, with at least two rotating stirrers wherein at least one of the stirrers is a helical or anchor agitator arranged centrally in the housing, and at least one of the other stirrers is an eccentrically arranged worm or blade stirrer.
• Spiral systems [Tatterson, G.B .; Fluid mixing and gas dispersion in agitated tanks; McGraw-Hill Inc .; 1991; P. 325ffJ. Spiral mixers are common mixer geometries for homogenizing higher-viscosity products.
• GB 2076675A describes trough mixers with helical mixer geometry. They are often used for mixing bulk goods or pasty media. These horizontally arranged mixers have the disadvantage that their housings can be shaped in complex and thus expensive geometric shapes have to. Furthermore, it is disadvantageous that the mixers are to be operated with their housing only in a horizontal arrangement.
• a mixer comprising at least one housing (1), at least two rotating stirrers (2) and (3) and optionally transverse bars for fixing the stirring elements of the centric rotor, wherein at least one of the stirrer (2) has a centric in Housing (1) arranged Wendel ⁇ or anchor agitator is, and at least one of the other agitator (3) is an eccentrically arranged worm or blade stirrer, fulfilling the object of the invention.
• the invention therefore relates to a mixer comprising at least housing (1), preferably with at least one filling and emptying opening, at least two rotating stirrers (2) and (3) and optionally transverse bars for fixing the stirring elements of the centric rotor, which is characterized in that at least one of the stirrers (2) arranged centrally in the housing (1) is a helix or anchor agitator and at least one of the other agitators (3) is an eccentrically arranged worm or blade stirrer.
• Gear technology an input shaft and at least two output shafts are used. By the transmission here a fixed speed ratio between the two stirrers is realized. Depending on the selected gradient and diameter ratios, the speed ratio of the two stirrers must remain constant during operation, since collisions of the two stirrers occur without a synchronization that is almost free from play. For types of mixer where the speed ratio is independent of the geometry - A -
• helical stirrers are understood as meaning mixers which are characterized by a shaft which is arranged centrically to the stirring elements and is optionally connected to the stirring elements via at least one transverse bar.
• the stirring elements of the helical stirrer can be made of a simple sheet metal or of hollow or solid material with a profiled cross-section. They form a helix (helix) of the slope S, which is arranged concentrically to the shaft.
• helical stirrers are understood here also those constructions whose slope S is due to the design changes with the circumferential length or the circumferential angle, as is the case for example in the stirrers described in DE 4117773 Al.
• mixer which are characterized by a preferably centrally arranged shaft and stirring elements, which are helically arranged (helical) with the slope S around the shaft, preferably no or only a small gap between the
• helical stirrers and screw stirrers in the sense of this document also include the case in which the pitch of the helix or helix is infinitely large in the mathematical sense. Then the helical stirrer passes into an anchor stirrer and the screw stirrer into a blade stirrer.
• Anchor stirrer and blade stirrer in the sense of this document are understood to mean all technical designs according to the armature geometry, as described, for example, in: Ullmann's
• stirrer arms can also be formed by interrupted or offset elements attached.
• elements for example, rods with round or triangular or square
• Cross section or helical segments are used.
• the housing has a substantially circular cross-section, deviations tolerated for example due to manufacturing tolerances in the ovality of containers.
• the bottom of the housing may have any common shapes, such as
• Example dished bottom, basket bottom or conical tapered bottom shapes The ground anchor shape following the helical stirrer can be adapted to the shape of the ground without mixing disadvantages.
• the anchor shape can have an S-shaped or straight shape when viewed in horizontal section.
• the mixer has at least one opening for filling and / or emptying.
• the mixer has at least one opening for filling and / or emptying.
• Embodiments with at least one respective filling and emptying opening are particularly preferred.
• the mixers according to the invention are also characterized in that at least one eccentric stirrer (3) and at least one centric stirrer (2) rotate in opposite directions or in the same direction, very particularly preferably in the same direction.
• a mixer is preferred, which is characterized in that at least one eccentric screw mixer is in engagement with the centric helical stirrer, ie that the outside diameter of an eccentric stirrer intersects the inside diameter of the helical stirrer in a cross section perpendicular to the shafts.
• the relationship is the radial overlap length (e) and the coil width (b) in a section perpendicular to the waves understood. This is sketched by way of example in FIG. 2.
• the intervention amounts to 30 to 99%, preferably 80 to 95%.
• a further relevant parameter of the mixer according to the invention is the number of flights of the stirrer.
• the number of flights of a helical or Schneckenrrockers is to be understood in the following the natural number, which results when dividing the angle 360 ° by the angle by which a stirrer must be rotated about its axis, so that the image of its section with a Level perpendicular to the stirrer shaft with the corresponding output sectional image coincides.
• mixers in which the number of turns of the armature or helical stirrer is 2. This has the advantage that during the rotation of this stirrer symmetrical conditions prevail about its axis, so that hardly any flow forces occur perpendicular to the stirrer shaft. On the other hand, the manufacturing expense for the production of the stirrer due to the lower
• the pitch of the stirrer is also a variable influencing the mixer.
• the pitch of a helical or worm stirrer is here the ratio of unwound height and unwound circumferential length, when unrolling a stirrer on the outer circumference on a plane and the positions, which passes through the contact point of the stirring blade with the plane by a line. The slope of this line is then the pitch of the stirrer.
• the pitch of spiral and worm stirrer is chosen to be constant.
• the pitches of the stirrers should therefore preferably behave inversely proportional to the peripheral speeds of the stirrers so that the vertical distances x u and x 0 between the two agitating blades remain nearly constant during engagement during movement.
• the pitch of the helical stirrer can be between 0.05 and infinite. In a preferred embodiment of the invention, the pitch of the helical stirrer is between 0.1 and 2.
• the speed ratio of screw to spiral impeller is in the range between
• the mixer according to the invention preferably has a speed ratio of screw to helical stirrer of 4: 1 to 2: 1, particularly preferably of 3: 1.
• This design of the helical stirrer is particularly advantageous because it allows the worm stirrer to engage practically as deeply in the helical stirrer as without the stiffeners, which leads to a particularly good mixing action of the entire mixer.
• the pitch directions, pitches, speeds, and directions of rotation of the stirrers can be independently selected.
• the centric and an eccentric stirrer are in mutual engagement and the pitches of these two stirrers are coordinated so that the vertical spacing between the stirrer blades remains as constant and uniform as possible during engagement of the stirrer.
• At least one eccentric stirrer (3) and at least one centric stirrer rotate in opposite directions.
• the mixers In reverse rotation, the mixers must not be engaged. Furthermore, the mixer preferably has a number of revolutions for the helical or anchor agitator of 2 and the number of threads for the helical or blade agitator of 1 or 2 in counter-rotating mixers.
• the pitch can also be chosen as desired, as well as the speed ratio.
• a mixer with counter-rotating stirrers may have stiffeners. These are then possible both on the helical outer diameter and on the helical inner diameter.
• the housing does not have to be completely provided with the internals according to the invention. It can e.g. for certain processes (degassing) a gas space above the stirrer installations be kept free.
• the mixers according to the invention surprisingly showed that the mixing times of these mixers are considerably shortened compared with conventional, comparable stirrers (spiral stirrers), in particular when the screw stirrer engages deeply in the helical stirrer, and the stirrers with a
• the mixers according to the invention have heating or cooling elements on the inner wall of the housing.
• the housing may also be provided per se with the known conventional cooling or heating means, e.g. with a through-flow of heat transfer double jacket, electric heating coils etc.
• the mixer according to the invention is suitable for any mixing tasks in the chemical process technology, of course, as a reactor for stirred reactions.
• the mixer can also be used as a horizontal mixer, i. E. with horizontally arranged waves, operated.
• a horizontal arrangement of the shafts is useful, for example, for processes involving bulk goods or moist bulk materials.
• all other angles of inclination of the waves relative to the vertical between 0 and 90 ° are possible.
• Figure Ia is the front view of a mixer according to the invention; the housing (1) is shown in section.
• FIG. 1 b shows the front view of a mixer according to the invention, with pitches of spiral and worm stirrers which are larger than those of FIG.
• Figure Ic is the front view of a mixer according to the invention with respect to Figure Ia increased gradients, in which reinforcing rods (5) on the outer diameter of the helical stirrer (2) are mounted.
• the housing
• Figure 1 shows a section through a mixer according to the invention with the number of gears two for the coil (2) and the number of gears two for the screw (3).
• the figure also shows the depth of engagement (e) and the helix width (b), from which the percentage engagement E is calculated.
• FIG. 3 shows a section through another mixer according to the invention, in which the number of turns of the helical stirrer (2) two and the number of turns of the
• Worm stirrer (3) is one.
• Figure 4 shows a section through a mixer according to the invention, in the helix
• Figure 5 shows a section through a mixer according to the invention, in which for improving the mechanical stability reinforcing rods (5) are mounted parallel to the shaft on the outer diameter of the helical stirrer (2).
• Figures Ia, Ib and Ic show inventive mixer in the side view in different embodiments.
• FIG. 1c additionally shows the reinforcing rods (5) mounted parallel to the shaft.
• both the sense of rotation and the pitch of both stirrers must be identical. It also requires a synchronizing drive for both stirrers, which ensures that the two stirrers move at a fixed speed ratio and the stirring blades do not come into contact with each other.
• FIG. 2 shows a cross section through a mixer according to the invention.
• the number of turns of the spiral agitator (2) and of the worm agitator (3) is two.
• Mixer can be operated with a speed ratio of screw to 3: 1 or 2: 1 helical stirrer. For a precise tuning of the slopes for the purpose of large and safe vertical distances in engagement between the two
• the pitch S 2 0.85 (corresponding to a pitch angle of 40.6 °) is selected for the eccentric worm stirrer ) at a speed ratio of 3: 1 and the
• FIG. 4 shows a variant of the mixer according to the invention, in which the centric helical stirrer (2) and the eccentric screw stirrer (3) are not in mutual engagement. Now both the direction of rotation and the pitch of both stirrers can be selected independently of each other. In addition, no synchronizing transmission with a fixed speed ratio is required here. It is now possible to adjust the conveying direction of both stirrers independently of each other so that either both stirrers have the same or different conveying directions axially.
• FIG. 5 shows a variant of the mixer according to the invention, in which the centric helical stirrer (2) and the eccentric worm stirrer (3) are in mutual engagement and are driven synchronously.
• four stiffening rods (4) are mounted parallel to the shafts on the outer diameter of the helical stirrer. hereby the entire construction of the helical stirrer is very efficiently stiffened against elastic and plastic deformation, without obstructing the engagement between the helical and the helical stirrer, which is important for shortening the mixing times.

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• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Mixers Of The Rotary Stirring Type (AREA)
• Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
• Preparation Of Compounds By Using Micro-Organisms (AREA)

Priority Applications (5)

Applications Claiming Priority (2)

Publications (1)

Family

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Family Applications (1)

Country Status (7)

Cited By (3)

Families Citing this family (20)

Citations (3)

Family Cites Families (10)

• 2004
  • 2004-07-16 DE DE102004034395A patent/DE102004034395A1/de not_active Withdrawn
• 2005
  • 2005-07-02 JP JP2007520708A patent/JP2008506512A/ja active Pending
  • 2005-07-02 EP EP05762079A patent/EP1771241B1/de not_active Expired - Lifetime
  • 2005-07-02 DE DE502005006704T patent/DE502005006704D1/de not_active Expired - Lifetime
  • 2005-07-02 AT AT05762079T patent/ATE423616T1/de not_active IP Right Cessation
  • 2005-07-02 WO PCT/EP2005/007177 patent/WO2006007967A1/de not_active Ceased
  • 2005-07-02 CN CN2005800311813A patent/CN101022883B/zh not_active Expired - Fee Related
  • 2005-07-02 US US11/572,146 patent/US7871193B2/en not_active Expired - Fee Related

Patent Citations (3)

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