EP0071454B1 - Mélangeur statique - Google Patents

Mélangeur statique Download PDF

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Publication number
EP0071454B1
EP0071454B1 EP82303951A EP82303951A EP0071454B1 EP 0071454 B1 EP0071454 B1 EP 0071454B1 EP 82303951 A EP82303951 A EP 82303951A EP 82303951 A EP82303951 A EP 82303951A EP 0071454 B1 EP0071454 B1 EP 0071454B1
Authority
EP
European Patent Office
Prior art keywords
conduit
central plate
plate
plates
mixer element
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP82303951A
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German (de)
English (en)
Other versions
EP0071454A1 (fr
Inventor
Henry Mccallum
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
STATIFLO Inc
Original Assignee
STATIFLO Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by STATIFLO Inc filed Critical STATIFLO Inc
Priority to AT82303951T priority Critical patent/ATE24283T1/de
Publication of EP0071454A1 publication Critical patent/EP0071454A1/fr
Application granted granted Critical
Publication of EP0071454B1 publication Critical patent/EP0071454B1/fr
Expired legal-status Critical Current

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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
    • B01F25/43—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
    • B01F25/4315—Straight mixing tubes with baffles or obstructions that do not cause substantial pressure drop; Baffles therefor the baffles being deformed flat pieces of material
    • B01F25/43151—Straight mixing tubes with baffles or obstructions that do not cause substantial pressure drop; Baffles therefor the baffles being deformed flat pieces of material composed of consecutive sections of deformed flat pieces of material

Definitions

  • This invention relates to static or in-line mixers which incorporate a plurality of stationary baffles to deflect the flow of materials through a conduit thereby effecting a mixing or dispertion of the materials during transport through the conduit.
  • a smooth helical structure formed by twisting a sheet or plate of metal to provide 180 degrees of rotation between leading and trailing edges of the sheet or plate is a particularly effective mixing element for circular conduits.
  • These helical structures can be constructed as left or right hand elements ("left” or “right” being determined by whether the flow pathways defined by such an element curve counterclockwise or clockwise respectively in the direction of material ' flow).
  • Such left and right hand elements can be connected in series with leading edges substantially perpendicular to trailing edges to provide a very effective flow dividing and recombining arrangement.
  • Such' mixer elements provide effective radial mixing of flowable materials, eliminating radial gradients in composition, temperature and velocity, and can be readily dimensioned to provide flows of varying degrees of turbulence.
  • the described -embodiment of the invention moreover provides a mixer element constructed as a plurality of plates, which approximates to the function of a smooth helical mixer element, but can be constructed more easily than such mixer elements for relatively large conduit diameters (5 to 10 inches, or 12.7 to 25.4 centimetres and above).
  • the mixer element comprises seven plate elements, some of which may be integrally formed by bending from an appropriate blank.
  • These plate elements include a central plate, preferably in the form of a substantially parallelogram-shaped plate having a first pair of diagonally opposite vertices, and a second pair of diagonally opposite vertices spaced to contact the walls of a conduit.
  • the mixer element also includes two end plates which are substantially triangular in form. These end plates are substantially co-planar and disposed perpendicular to the plane of the parallelogram-shaped plate. A vertex of each end plate is substantially co-incident with one of the first pair of diagonally opposite vertices of the central plate. The base of each end plate provides either a leading edge for dividing fluid flows into two parts, or a trailing edge where a succeeding mixer element can be located. The two remaining vertices of each triangular plate are spaced to contact walls of the conduit when installed.
  • each deflector plate extends one from each side of the parallelogram-shaped central plate to a side of the triangular end plates (except the bases of the triangular plates which provide the leading and trailing edges) so that two separate flow paths are defined.
  • each deflector plate has a sealing edge which conforms to the contours of the inner walls of the conduit.
  • the deflector plates are so connected to the end and central plates that each flow path spirals substantially helically through about 180° of rotation, between the leading and trailing edges of a mixer element. These spiralling flow paths provide the desired rotation and mixing of materials in use.
  • sealing contemplates the possibility of some fluid channelling between fluid flow paths.
  • a clearance of one percent of the internal diameter of a conduit is commonly tolerated about a mixer element in the conduit.
  • it is usually provided by welding, soldering or otherwise, after installation of mixer elements.
  • FIG. 1 A preferred embodiment of a static mixer 10 is illustrated in the perspective view of Fig. 1.
  • the static mixer 10 comprises a circular-section steel conduit 12 containing a plurality of steel left and right hand mixer elements of substantially identical structure.
  • the conduit 12 is broken away at 14 to better illustrate two mixer elements 16, 18.
  • the contemplated direction of material flow is indicated by arrows F in the view of Fig. 1.
  • the materials can be liquids, gases, solids (granular or powder) or combinations thereof, as contemplated by the prior art.
  • the flows can be effected under vacuum, positive pumping pressure, or gravity feed.
  • the mixer element 16 is a right hand element, and the succeeding mixer element 18 is a left hand element.
  • the mixer element 16 has leading and trailing edges 20, 22 which are substantially parallel to one another and perpendicular to inner walls 24 of the conduit 12. It is not critical to the function of mixer elements that the trailing and leading edges be so oriented: the leading edge need only divide the flow of material entering the mixer element into two streams, and the trailing edge should be shaped to permit a succeeding mixer element to be abutted in series with the particular mixer element.
  • Mixer element 16 provides two separate, substantially helical flow paths indicated by arrows 30, 32 in Fig. 1.
  • the leading edge 20 is positioned to divide the flow in conduit 12 evenly between the flow paths 30, 32 (assuming that the full cross-sectional area of the conduit 12 is being used in the transport of materials).
  • the rotation and deflection of the materials along the surfaces defining the helical paths 30, 32 provides a thorough mixing of the materials.
  • Mixing of materials is effected substantially in three ways: division and recombination of flows in succeeding mixer elements; radial mixing; and turbulence in the individual elements.
  • Turbulence effects depend largely on geometry and pitch (herein defined as the ratio of the axial length of a mixer element to conduit diameter, which diameter may be some appropriate average cross-sectional diameter in the case of non- circular conduit), and are disclosed in the prior art.
  • An angle of 0 to 90 degrees can be provided between the trailing edge of one mixer element and the leading edge of a succeeding mixer element, but 90 degrees is considered optimal for mixing by division and recombination of flows.
  • An angle of 0 degrees may be suitable in applications where the flows through individual mixer elements are designed to be particularly turbulent.
  • the right hand mixer element 16 is better illustrated in the view of Figs. 2-4, where it will be seen to be constructed in seven substantially plate members. These members include a substantially rhombus parallelogram-shaped central plate 34 with sides of equal length (best illustrated in the view of Fig. 4). A first pair of sides 36, 38 intersect to define a first central plate vertex 40, and a second pair of sides 42, 44 intersect to define a second central plate vertex 46, diagonally opposite to the first vertex 40. The remaining pair of diagonally opposite vertices 47, 49 of the plate 34 are spaced to contact the inner walls 24 of the conduit 12.
  • the mixer element 16 also includes a pair of triangular end plates 48, 50 (best illustrated in the view of Fig. 2). These end plates 48, 50 are substantially co-planar and perpendicular to the plane of central plate 34. The bases of the end plates 48, 50 define the leading and trailing edges 20, 22 respectively.
  • the end plate 48 has a pair of lateral edge vertices 52, and the end plate 50, a pair of lateral edge vertices 54, which vertices are in contact with the inner walls 24 of the conduit 12.
  • the end plate 48 has two equal sides 56, 58 which intersect to define an inner vertex 60, substantially co-incident with the vertex 40 of central plate 34.
  • the end plate 50 has two equal sides 62, 64 which sides intersect to define an inner vertex 80 co-incident with the vertex 46 of the central plate 34.
  • Each deflector plate extends from each side of central plate 34 continuously to one of the sides of the two end plates 48, 50.
  • Each deflector plate has a sealing edge 74 which extends from one of the vertices 47, 49 (contacting the inner walls 24 of the conduit 12) of central plate 34 to one of the pair of third and fourth vertices 52, 54 (contacting the inner walls 24 of the conduit 12) of the end plates 48, 50.
  • These sealing edges 74 are shaped to conform to the contours of the inner walls 24 of conduit 12, whereby the flow paths 30, 32 are kept separate (not in fluid communication through substantially the full length of the mixer element 16).
  • the orientation of the deflector plates is such that the paths 30, 32 spiral in a substantially helical fashion through about. 180 degrees of rotation (as mentioned above). It is not critical to the operation of the mixer elements that exactly 180 degrees of rotation be achieved.
  • seven plates can be individually cut, then welded, soldered or otherwise fastened, to form the mixer element 16.
  • Individual forming of the plates may in fact be preferred if the diameter of the mixer element is in the order of several feet.
  • several plates can be integrally formed from a single sheet or plate of metal and then appropriately bent. Sharp edges between the plates are clearly not necessary, and smooth curved surface at plate jointures may in fact be preferred. Additionally, it is not critical that the plates be "planar", although this may be preferable when forming the elements from blanks.
  • Fig. 5 illustrates a blank 76 which together with the two end plates 48, 50 can be used to form the mixer elements 16.
  • the following parameters are indicated:
  • Bend lines 78 indicate, of course, where the blank 76 is to be bent, to a fixed bend angle.
  • the direction of bending to obtain the required helical flow paths 30, 32 will be obvious from the views of Figs. 2-4.
  • the height of the end plates 48, 50 (as measured perpendicular to the leading and trailing edges) has been selected to be L/4 units, and diagonals of the central plate 34 have been selected to be U2 units, where L is the axial length of the mixer element.
  • the pitch of a mixer element will typically be 1:1 to 1.5:1, but is not limited to such ranges. Additionally, the relative axial widths of the central and end plates can be varied significantly.
  • the left hand mixer element 18 can be formed as well from the blank 76 together with the end plates 48, 50.
  • the deflector plates will be bent through the same bend angle calculated, but in opposite directions relative to the central plate 34.
  • the mixer elements 16, 18 described above are adapted for use in a cylindrical conduit.
  • the sealing edges of the deflector plates can be shaped for sealing engagement with the inner walls of conduits of rectangular or elliptical or other cross-sectional shapes.
  • the relative spacing of the vertices of the triangular plates and the vertices of the rhomboid central plate that must contact the walls of the conduit will be readily apparent in any particular application, being dictated by the internal dimensions of the conduit.
  • the dimensions for the deflector plate edges can be accurately calculated for best fit in any given conduit.
  • Mixer elements constructed according to the invention and having different pitches and different angles between leading and trailing edges of succeeding stages can be combined in a single in-line mixer to obtain various mixing and dispersion effects.

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  • Chemical & Material Sciences (AREA)
  • Dispersion Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Mixers Of The Rotary Stirring Type (AREA)

Claims (9)

1. Elément mélangeur statique (16) qui peut être placé dans un conduit (12) et qui comprend une plaque centrale (34), sous la forme d'un quadrilatère comportant une première et une deuxième paires de côtés (36, 38; 42, 44), et quatre éléments déflecteurs (66, 68, 70, 72) fixés chacun à un bord de la plaque centrale et formant un prolongement de la plaque centrale de manière à dévier un fluide qui circule dans le conduit, chaque élément déflecteur présentant un deuxième bord (74) en conformité aux contours intérieurs du conduit (12), caractérisé en ce que lesdits éléments déflecteurs sont fixés un à chaque bord latéral de la plaque quadrangulaire centrale et constituent des extensions latérales desdits bords latéraux de la plaque centrale (34), la disposition étant telle que, en utilisation, une paire de sommets opposés (47, 49) de ladite plaque centrale peuvent venir en contact avec des surfaces intérieurs opposées du conduit (12), et l'autre paire de sommets (40, 46) de la plaque central peuvent être situés entre lesdites surfaces intérieures du conduit et séparés dans la direction d'écoulement du fluide, les éléments déflecteurs successifs autour de la périphérie de la plaque centrale étant inclinés dans des sens opposés par rapport au plan de la plaque centrale, de sorte qu'un premier et un deuxième passages d'écoulement hélicoïdaux séparés sont définis sur la longueur de l'élément mélangeur, et une première et une deuxième plaques d'extrémité (48, 50) sont situées à ladite autre paire de sommets (40, 46) de la plaque central, chaque . plaque d'extrémité comportant des bords latéraux (56, 58 et 62, 64) qui se coupent pour définir un sommet (60,80) de plaque d'extrémité, lesdits bords latéraux (56, 58 et 62, 64) de plaque d'extrémité et les sommets (60, 80) de plaque d'extrémité étant fixés respectivement à un troisième bord de chacune des deux plaques déflectrices adjacentes (68, 66 et 72, 70) et à ladite autre paire de sommets (40, 46) de la plaque centrale.
2. Elément mélangeur statique suivant la revendication 1, caractérisé en ce que la plaque centrale (34) est sous la forme d'un parallélogramme.
3. Elément mélangeur statique suivant la revendication 1, caractérisé en ce que les plaques d'extrémité (48, 50) sont dans un même plan et se trouvent dans des plans perpendiculaires au plan de la plaque central (34).
4. Elément mélangeur statique suivant la revendication 1 ou la revendication 3, caractérisé en ce que les plaques d'extrémité (48, 50) sont sensiblement de forme triangulaire.
5. Elément mélangeur statique suivant l'une quelconque des revendications 1, 3 ou 4, caractérisé en ce que la plaque centrale (34) et les plaques d'extrémité (48, 50) et les plaques déflectrices (66,68,70,72) sont montées dans des attitudes telles que, lorsque l'élément mélangeur (16) est placé dans le conduit (12), les passages d'écoulement ainsi définis ont des sections transversales.de surface sensiblement égale dans . tout plan perpendiculaire à l'axe d'écoulement du conduit et coupant les passages d'écoulement, sensiblement sur toute la longueur des passages d'écoulement.
6. Elément mélangeur statique suivant la revendication 4, caractérisé en ce que les quatre côtés des deux plaque triangulaires d'extrémité, définissant les sommets (60, 80) de ces plaques adjacents aux autres sommets (40, 46) de la plaque centrale, sont tous de longueur sensiblement égale.
7. Mélangeur statique comprenant un conduit (12) qui contient une pluralité d'éléments mélangeurs fixes (16) suivant l'une quelconque des revendications précédentes..
8. Mélangeur statique suivant la revendication 7, caractérisé en ce que les éléments mélangeurs successifs (16) sont de construction à gauche et à droite.
9. Mélangeur statique suivant la revendication 7 ou la revendication 8, caractérisé en ce que les éléments mélangeurs successifs (16) ont leurs plaques centrales (34) disposées sensiblement perpendiculairement les unes aux autres.
EP82303951A 1981-07-28 1982-07-27 Mélangeur statique Expired EP0071454B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT82303951T ATE24283T1 (de) 1981-07-28 1982-07-27 Statischer mischer.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CA382702 1981-07-28
CA382702 1981-07-28

Publications (2)

Publication Number Publication Date
EP0071454A1 EP0071454A1 (fr) 1983-02-09
EP0071454B1 true EP0071454B1 (fr) 1986-12-17

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ID=4120547

Family Applications (1)

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EP82303951A Expired EP0071454B1 (fr) 1981-07-28 1982-07-27 Mélangeur statique

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EP (1) EP0071454B1 (fr)
AT (1) ATE24283T1 (fr)
DE (1) DE3274720D1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6136272A (en) * 1997-09-26 2000-10-24 University Of Washington Device for rapidly joining and splitting fluid layers
DE19748383C2 (de) * 1997-11-03 2000-11-23 U & A Gmbh Statischer Mischer

Families Citing this family (11)

* Cited by examiner, † Cited by third party
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US5650173A (en) * 1993-11-19 1997-07-22 Alkermes Controlled Therapeutics Inc. Ii Preparation of biodegradable microparticles containing a biologically active agent
EP1649850A1 (fr) * 1993-11-19 2006-04-26 Alkermes Controlled Therapeutics Inc. II Préparation des microparticules biodégradables contenant un agent biologiquement actif
NZ276088A (en) 1993-11-19 1999-07-29 Janssen Pharmaceutica Nv [(1,2-benzisoxazol-3-yl)-1-piperidinyl-alkyl-6,7,8,9-tetrahydro-4h- pyrido[1,2-a]-pyrimidin-4-one derivatives (ie risperidone)
DE19700462C2 (de) * 1997-01-09 1999-07-01 Guenther Schwald Statischer Mischer
ES2309445T3 (es) 2004-12-17 2008-12-16 Borealis Technology Oy Proceso para la polimerizacion de olefinas en presencia de un catalizador de polimerizacion de las mismas.
GB0820644D0 (en) 2008-11-12 2008-12-17 Statiflo Internat Ltd UV Irradiation apparatus and method
US7946753B2 (en) 2009-08-31 2011-05-24 Dow Global Technologies Llc Rotatable mixing device and dynamic mixing method
EP3241611B1 (fr) 2016-05-02 2020-03-04 Borealis AG Procédé d'alimentation d'un catalyseur de polymérisation
WO2017220425A1 (fr) 2016-06-23 2017-12-28 Agfa Nv Photo-initiateurs polymérisables
FR3059410B1 (fr) * 2016-11-30 2019-07-19 Valeo Systemes Thermiques Organe de mixage constitutif d'un dispositif d'homogeneisation de la distribution d'un fluide refrigerant a l'interieur de tubes d'un echangeur de chaleur
JP7247163B2 (ja) * 2017-07-12 2023-03-28 ノードソン コーポレーション 三角形混合導管を備えた静的ミキサ

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3643927A (en) * 1970-10-15 1972-02-22 Phillips Petroleum Co Stationary mixture and method for mixing material
US3923288A (en) * 1973-12-27 1975-12-02 Komax Systems Inc Material mixing apparatus
US4034965A (en) * 1973-12-27 1977-07-12 Komax Systems, Inc. Material distributing and mixing apparatus
US4179222A (en) * 1978-01-11 1979-12-18 Systematix Controls, Inc. Flow turbulence generating and mixing device
US4208136A (en) * 1978-12-01 1980-06-17 Komax Systems, Inc. Static mixing apparatus

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6136272A (en) * 1997-09-26 2000-10-24 University Of Washington Device for rapidly joining and splitting fluid layers
DE19748383C2 (de) * 1997-11-03 2000-11-23 U & A Gmbh Statischer Mischer

Also Published As

Publication number Publication date
EP0071454A1 (fr) 1983-02-09
DE3274720D1 (en) 1987-01-29
ATE24283T1 (de) 1987-01-15

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