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Publication numberUS3620507 A
Publication typeGrant
Publication dateNov 16, 1971
Filing dateJan 7, 1970
Priority dateJan 7, 1970
Publication numberUS 3620507 A, US 3620507A, US-A-3620507, US3620507 A, US3620507A
InventorsKruka Vitold R
Original AssigneeShell Oil Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Method for rapidly mixing fluids
US 3620507 A
Abstract  available in
Images(2)
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Claims  available in
Description  (OCR text may contain errors)

United States Patent Inventor Vitold 1R. Kruka Houston. Tex.

Appl. No. 1.160

Filed Jan. 7, 1970 Patented Nov. 16, 1971 Assignee Shell Oil Company New York, N.Y.

METHOD FOR RAPIDLY MIXING FLUIDS 3 Claims, 4 Drawing Figs.

U.S. Cl 259/25 Int. Cl 801i 7/02 Field oi'Search 259/l8.4. 9. IO, 25, 26. 36, 45. 46

References Cited UNITED STATES PATENTS 12/1950 Fash 1831.754 4/1958 Manka 4. 259/4 X 3 l47 7l7 9/l964 Smith, 259/4 X 3.286.992 ll/l966 Armeniades 4 4 i 259/4 Primary Examiner-Robert W Jenkins Armrneys-Louis J. Bovasso and J H McCarthy ABSTRACT: A method for rapidly mixing at least one fluid into another by disposing a first fluid within a first conduit and flowing a second fluid within a second conduit substantially concentric with and disposed within the first conduit, the second conduit opening into contact with the fluid within the first conduit. An angular momentum is imparted to the second fluid within the second conduit to thereby form a swirling jet of the second fluid as it exits from the second conduit into contact with the fluid disposed in the first conduit PATENTEnunv 16 I97! 8.620, 507' sum 1 or 2 INVENTOR:

VITOLD R. KRUKA oZ M HIS ATTORNEY PATENTEDuuv 16 I971 3, 620.507

sum 2 OF 2 INVENTOR:

VITOLD R. KRUKA BWJW HIS ATTORNEY BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to the mixing of fluids; and, more particularly, to a method for rapidly mixing one fluid into another.

2. Description of the Prior Art Rapid mixing of fluids is necessary whenever it is undesirable to have the two or more fluids, which are to be mixed, in contact with each other in an unmixed state over extended periods of time. For example, a paraxylene unit was found to produce crystals too small in size which led to the waste discharge of approximately percent of the production. Indications were that this condition was due to an overproduction of crystal nueleii which in turn is strongly dependent on the level of local supersaturation.

In this paraxylene unit, a stream rich in paraxylene is fed into a reactor whose fluid phase has a low paraxylene content and a lower temperature than the feed. If the feed maintains itself in lumps over extended periods of time, then local supersaturation occurs as molecular transfer of heat is higher than that of mass. Thus, the longevity of the unmixed feed lumps determines the number of nucleation sites and final crystal size. To increase the crystal size, the average lifetime of the unmixed fluid lumps must be decreased.

Certain prior art patents are directed to the mixing of fluids. These patents, however, fail to achieve rapid mixing rates. For example, in US. Pat. No. 3,286,992, two fluids are mixed in a tube and are in contact with curved elements therein which split the incoming fluids, already in contact with each other, into two streams. Eddying motion is imparted to each stream to promote mixing. However, such action is not rapid as the two fluids coexist in the tube as unmixed lumps for a substantial amount of time. The same comments apply to the method disclosed in US. Pat. No. 3,424,347 where two viscous fluids are injected into a plurality of finned tubes under laminar flow conditions. Mixing, implied to occur inside the tubes, is achieved by subdivision and interlacing of the fluid streamlines.

SUMMARY OF THE INVENTION It is an object of this invention to provide an improved method of rapidly mixing one fluid into another.

It is a further object of this invention to provide a method of rapidly mixing one fluid into another whereby the rate of mixing may be controlled.

These and other objects are preferably accomplished by disposing a first fluid within a first conduit and flowing a second fluid within a second conduit substantially concentric with and disposed within the first conduit, the second conduit opening into contact with the fluid within the first conduit. An angular momentum is imparted to the second fluid within the second conduit to thereby form a swirling jet of the second fluid as it exits from the second conduit into contact with the fluid disposed in the first conduit.

The fluid to be mixed is injected into the other which may be at rest, as in a batch-type reactor, or which may be flowing at a lower velocity than the first fluid. The angular momentum may be imparted to the fluid either by internal or external means.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is an isometric view of a preferred embodiment of apparatus for carrying out the method of my invention;

FIG. 2 is an isometric view, partly in section, of a portion of the apparatus of FIG. 1;

FIG. 3 is an isometric view of an alternate embodiment of apparatus for carrying out the method of my invention; and

FIG. 4 is a sectional view taken along the line 4-4 of FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawing, FIG. 1 shows an outer conduit I0 having a first fluid flowing therethrough in the direction of arrows 11. A second conduit 12, substantially concentric with conduit 10, is disposed internally thereof. A second fluid is adapted to be flowed in conduit 12 as indicated by the arrow I4. Although both fluids are shown in FIG. I as flowing through conduits 10 and 12, the fluid in conduit 10 may be either at rest or flowing at a lower velocity than the jet of fluid from conduit 12 as will be discussed further hereinbelow.

A swirl or angular momentum is imparted to the fluid exiting from conduit 12. The phrase angular momentum refers to a change in the normal spread of the fluid exiting from conduit 12. For example, as illustrated in FIG. 2, a helix 15 having a plurality of helical fins 15a, is preferably fixedly mounted in conduit 12. In this manner, low values of swirl may be imparted to the fluid exiting from conduit 12 thus fonning a swirling jet 16 (FIG. 1) of fluid. The dotted lines in FIG. I indicate the spread of the fluid which would be fonned by not swirling the fluid. Thus, it can be seen that the helical fins 15a disperse or mix the fluid from conduit I2 into the fluid in conduit 10 more rapidly in both space and time. The ratio of angular to linear jet momentum may be controlled by varying the pitch of helix 15.

Thus, the rate of mixing of a swirling jet above that of a nonswirling jet may be controlled by the amount of angular momentum given to the jet. For higher values of swirl, the angular momentum may be imparted through external means. For example, as illustrated in FIG. 3, a further embodiment of the invention is shown wherein a first fluid is flowed in a conduit 16 in the direction of the arrow 17 while a second fluid is flowed in a conduit 18 in the direction of the arrow I9. Again, the fluid flowing in conduit 16 may be either at rest or flowing as discussed hereinabove. The external means for imparting angular momentum to the fluid in conduit 18 may take the form of a plurality of radially extending fins 20 having fingers 20a at their extremities (FIG. 4), mechanically or automatically rotated by a connecting shaft 21 (FIG. 3) preferably extending longitudinally of conduit 18 and coupled to actuating means (not shown), such as a motor or a handle. Note that fins 20 are substantially linearly extending and substantially perpendicular to the direction of the flowing fluid in conduit 18. In this manner, a swirling jet 22 is formed by the fluid exiting from conduit 18.

As set forth hereinabove, rapid mixing of one fluid into another may be achieved by forming a swirling jet at the point of contact of a first fluid with a second fluid. The mixing action is due to the dispersive qualities of the angular momentum imparted to the first fluid and the turbulence inherent in jets of sufficiently high Reynolds numbers. The fluid to be mixed is injected into the other fluid which may be at rest, as in a batch-type reactor, or which may be flowing, but at a lower velocity than the jet. This angular momentum may be imparted by either internal means, such as the fixed, helical fins 15a of the helix 15 of FIG. 2 or by external means, such as the radially and linearly extending rotating fins 20 of FIG. 4. The rate of mixing of the first fluid into the second fluid may be controlled by controlling the angular and linear momentum of the issuing fluid.

In one preferred use of the method of this invention, a stream rich in paraxylene may be fed into a reactor whose fluid phase has a low paraxylene content and preferably a lower temperature than the feed using either of the embodiments of the invention described hereinabove. In this manner, the feed is rapidly dispersed into the reactor contents from the combined angular momentum of the feed after it leaves the nozzle (i.e., the outlet of the second conduit) and the turbulence inherent in jet flows.

I claim as my invention:

1. A method for rapidly mixing at least one fluid into another comprising the steps of:

disposing a first fluid at rest within a first conduit;

flowing a second fluid within a second conduit substantially concentric with and disposed within said first conduit, said second conduit opening into the fluid within said first conduit; and

imparting an angular momentum only to said second fluid within said second conduit to thereby form a swirling jet of said second fluid as it exits from said second conduit into contact with the fluid disposed in said first conduit.

2. A method for rapidly mixing at least one fluid into another comprising the steps of:

disposing a first fluid within a first conduit;

flowing a second fluid within a second conduit substantially concentric with and disposed within said first conduit, said second conduit opening into the fluid within said first conduit; and

imparting an angular momentum to said second fiuid within said second conduit by rotating a plurality of radially extending fins in the path of said fluid flowing in said second conduit, said fins being substantially linearly extending and substantially perpendicular to the direction of the flowing fluid in said second conduit to thereby form a swirling jet of said second fluid as it exists from said second conduit into contactwith the fluid disposed in said first conduit.

3. A method for rapidly mixing at least one fluid into another comprising the steps of:

flowing a first fluid within a first conduit;

flowing a second fluid faster than said first fluid within a second conduit substantially concentric with and disposed within said first conduit, said second conduit opening into the fluid within said first conduit; and

imparting an angular momentum only to said second fluid within said second conduit to thereby form a swirling jet of said second fluid as it exits from said second conduit into contact with the fluid disposed in said first conduit.

'0' I I l t

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2534253 *Dec 28, 1943Dec 19, 1950Anderson Clayton & CoRefining apparatus
US2831754 *May 10, 1954Apr 22, 1958Jones & Laughlin Steel CorpSolvent extraction process
US3147717 *Feb 12, 1963Sep 8, 1964Smith Verle DBlending apparatus
US3286992 *Nov 29, 1965Nov 22, 1966Little Inc AMixing device
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4749527 *Sep 5, 1986Jun 7, 1988Rasmusen Hans CStatic aerator
US6099113 *Mar 13, 1998Aug 8, 2000Iris GraphicsContinuous jet printer mixing system
US6786565Sep 24, 2001Sep 7, 2004Creo Americas, Inc.Inkjet proofing with matched color and screen resolution
US6916078Sep 7, 2004Jul 12, 2005Creo Americas, Inc.Inkjet proofing with matched color and screen resolution
US7375857Sep 22, 2000May 20, 2008Eastman Kodak CompanyPrint proofing with color and screen matching
US8579495 *Sep 19, 2007Nov 12, 2013Basf SeProcess for mixing a liquid or mixture of a liquid and a fine solid present in an essentially self-containing vessel
US20050030330 *Sep 7, 2004Feb 10, 2005Adam I. PinardInkjet proofing with matched color and screen resolution
US20080074944 *Sep 19, 2007Mar 27, 2008Basf AktiengesellschaftProcess for mixing a liquid or mixture of a liquid and a fine solid present in an essentially self-containing vessel
EP1254699A1 *Apr 16, 2002Nov 6, 2002Robert Bosch GmbhMixer for gas in fuel cells
EP1800738A1 *Dec 23, 2005Jun 27, 2007Sika Technology AGDevice and method for producing an adhesive and/or sealant composition, adhesive and/or sealant composition thus produced, and bonded substrates
WO2007074139A1 *Dec 22, 2006Jul 5, 2007Sika Technology AgApparatus and process for forming an adhesive and/or sealant composition, adhesive and/or sealant composition produced in this way and adhesive-bonded substrates
Classifications
U.S. Classification366/155.2, 366/339, 366/158.5
International ClassificationB01F5/04, B01F5/00
Cooperative ClassificationB01F2005/0017, B01F5/0451
European ClassificationB01F5/04C13B