PROCESS AND APPARATUS FOR MECHANICALLY MIXING TWO IMMISCIBLE LIQUIDS AND ONE OR MORE OTHER SUBSTANCES

APPAREIL ET METHODE POUR MELANGER MECANIQUEMENT DEUX LIQUIDES NON MISCIBLES AVEC UNE OU DEUX AUTRES SUBSTANCES

English Abstract

PROCESS AND APPARATUS FOR MECHANICALLY MIXING TWO
IMMISCIBLE LIQUIDS AND ONE OR MORE OTHER SUBSTANCES
ABSTRACT
A process and apparatus are disclosed for mechan-
ically mixing two immiscible liquids and one or more other
substances by creating in the upper portion of the apparatus
a continuous dual-layer liquid film composed of upper and
lower layers of immiscible liquids such as oil and water,
into which film one or more substances in the gas, liquid,
powder, or a combined phase are dispersed and the resulting
dispersed mixture is further mixed and emulsified in the
lower portion of the apparatus under the action of shearing
forces. A portion of the oil to be mixed may be fed directly
into the lower portion of the apparatus for mixing with the
pre-emulsified mixture.

Claims

The embodiments of the invention in which an
exclusive property or privilege is claimed are defined as
follows:
1. A continuous flow mixer comprising:
tank means having two inlets for respectively
receiving two immiscible liquids therein;
means forming an inverted truncated conical
surface coaxially disposed within said tank means, and having
an upper circumferential rim communicating with the interior
of said tank means and a lower open end sealed from the
interior of said tank means,
means for feeding two immiscible liquids into said
tank means so as to over flow said rim and create a
continuous downwardly flowing dual-layer liquid film on said
conical surface from said rim to the open lower end;
means for feeding a third substance into said tank
means;
means for centrifugally dispersing said third
substance into said flowing liquid film on said conical
surface;
compartment means communicating with said lower
open end for receiving the downwardly flowing dual-layer
liquid film containing the third substance dispersed therein;
and
means in said compartment means for producing a
shearing action on the liquids and third substance therein to
mix and emulsify the two immiscible liquids and the third
substance dispersed therein.
2. A mixer as in claim 1 wherein the means for
producing a shearing action comprises two sets of relatively
moving operatively intermeshing pin members.
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3. A mixer as in claim 1 further comprising means for
feeding a liquid directly into said compartment means for
mixing with the immiscible liquids and the third substance
dispersed therein.
4. A mixer as in claim 1 further comprising means for
premixing said third substance with a fourth substance before
feeding it into said tank means.
5. A mixer as in claim 1 wherein said two inlets are
tangential inlets disposed in the wall of said tank means.
6. A mixer as in claim 1 wherein said liquid feeding
means comprises means for feeding the two liquids at constant
flow rates.
7. Apparatus for mechanically mixing two immiscible
liquids and one or more other substances comprising:
first and second coaxially disposed chambers, said
first chamber having two inlets therein;
means for feeding two immiscible liquids into said
first chamber respectively through said two inlets;
means for feeding a third substance into said first
chamber;
means, comprising a member containing a coaxially
disposed inverted truncated conical surface having an upper
circumferential rim communicating with said first chamber and
a lower open end communicating with said second chamber for
conducting said two liquids, in the form of a continuous
dual-layer liquid film flowing over the rim of the open upper
end and downwardly over the inverted conical surface of said
member, between said first and second chambers;
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first rotating means coaxially disposed within said
member in the path of flow of said third substance for
centrifugally dispersing said third substance into said
liquid film;
second rotating means coaxially disposed in said
second chamber; and
mixing means in said second chamber, including
means for rotating with said second rotating means, for
producing a shearing action on the liquids and third
substance in said second chamber to mix and emulsify the two
immiscible liquids and the third substance dispersed
therein.
8. Apparatus as in claim 7 wherein said first rotating
means comprises a rotating conical surface disposed within
the upper portion of said inverted conical surface.
9. Apparatus as in claim 7 wherein said second
rotating means comprises a rotating disk.
10. Apparatus as in claim 8 wherein said means for
rotating with said second rotating means comprises a
plurality of upstanding pins fixed on the upper surface of
said disk.
11. Apparatus as in claim 10 wherein said mixing means
comprises a plurality of stationary pins in said second
chamber and operatively intermeshing with said rotating
upstanding pins.
12. Apparatus as in claim 7 wherein said means for
feeding a third substance includes premixing means comprising
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means for producing an axial flow of said third substance and
means for producing a circulating flow of a fourth substance
in said axially flow.
13. A process for mechanically mixing two immiscible
liquids and one or more other substances comprising the steps
of:
feeding two immiscible liquids into a first
chamber, containing an inverted truncated conical surface
having an upper circumferential rim communicating with the
interior of said tank means and a lower open end sealed from
the interior of said tank means;
causing said immiscible liquids to flow over said
conical surface rim for creating a continuous downwardly
flowing dual-layer liquid film on said surface from said rim
to the upper lower end;
feeding a flow of a third substance into said first
chamber and centrifugally dispersing said third substance
into said downwardly flowing dual-layer liquid film;
receiving the downwardly flowing dual-layer liquid
film containing the third substance dispersed therein in a
second chamber through the open end of said truncated conical
surface; and
producing a shearing action on the liquids and
third substance in said second chamber to mix and emulsify
the two immiscible liquids and the third substance dispersed
therein.
14. A process as in claim 13 comprising the further
step of feeding liquid directly into said second chamber for
mixing with the immiscible liquids and the third substance
dispersed therein.

15. A process as in claim 13 wherein the shearing
action is produced by two sets of relatively moving
operatively intermeshing pin members.
16. A process as in claim 13 wherein said immiscible
liquids are oil and water.
17. A process as in claim 13 wherein said third
substance is pulverized coal.
18. A process as in claim 13 wherein said third
substance is in the form of a powder.
19. A process as in claim 13 further comprising the
step of premixing said third substance with a fourth
substance before feeding it to said first chamber.
20. A process as in claim 19 wherein said third and
fourth substances are mixed by producing a circulating flow
of said fourth substance and producing a flow of said third
substance axially into said circulating flow.
21. A process as in claim 13 wherein the two immiscible
liquids are fed at constant flow rates.
22. A process as in claim 13 wherein said third
substance is centrifugally dispersed by axially feeding the
flow onto a rotating conical surface.
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Description

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BACKGROUND OF THE INVENTION
.
The present invention relates to a process and
- apparatus for the continuous mechanical mixing of disparate
substances, such as oil, water, gas and fine particulate
material, in successive steps and ultimately under shearing
to produce evenly distributed mixtures or emulsions.
The mixtures produced with the present invention,
typically fuel emulsions and colloid fuel in emulsion, have
conventionally been produced using emulsification processes
requiring an emulsifying agent with attendant chemical reactions
and resulting impurities. The present invention, by way of
contrast, discloses a process and apparatus which continuously
and mechanically produce emulsions and suspensions more simply
than, and as effectively as, the prior art while obviating the
need for emulsifying agents.
The process and apparatus of the present invention
are modifications of and improvements upon those described in
U.S. Patent No. 3,871,625 issued on March 18, 1975 to Hiroyuki
Iwako and U.S. Patent No. 3,998,433 issued on December 21, 1976
to the same Iwako, one of the co-inventors of the present
invention.
SUMMARY OF THE INVENTION
The present invention involves the creation in a
suitable apparatus of a dual-layer liquid film, composed of
upper and lower layers of immiscible liquids such as oil and
water, into which film one or more substances in the gas,
liquid, powder, or a combined phase are dispersed, and the
resulting dispersed mixture is emulsified by mixing under
shearing.
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The mixing apparatus comprises an upper mixing
section in the form of a cylindrical tank containing a con-
centrically disposed inverted truncated overflow cone, and a
Lower section in the form of a mixing or emulsifying chamber
containing a mixing disk. A rotatable shaft extending con-
; centrically through the two sections is driven at its lower
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end and has a mixing cone fixed to its upper end for rotation
in the upper portion of the overflow cone. The dual-layer
liquid film is created on the inner surface of the overflow
~ ~0 cone by introducing a flow of two immiscible liquids, such
;~; as oil and water, into the cylindrical tank that overflows -
the upper rim of the overflow cone. An inlet pipe for the
, gas, liquid, powder, or combinations to be dispersed into ,
. :. . . .
~, the film is disposed concentrically above the mixing cone
~ . ,.. . ~, .
and may be adapted to conduct a swirling flow of, for exam-
ple when producing a fuel, a gas, such as air, premixed with
a fine powder or particulate matter, such as coal, for im-
pingement upon the rotating surface of the mixing cone.
The impinging material is centrifugally dispersed by the
mixing cone into the dual-layer liquid film. The film dis~
persed with the gas and particulate solids then passes through
the lower open end of the overflow cone into the mixing com-
partment. The mixing disk in the compartment is mounted
for rotation on the central portion of the rotary shaft
and has circular-arrays of upstanding pins on its upper
surface which cooperate with similar arrays of pins on the
bottom of the stationary cylindrical tank to produce a
.. ~ ..
shearing action on the incoming mixture to mix and emulsify
it. Scraper blades are provided on the lower surface of the
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mixing disk to further mix and move the resulting emulsion
out through an exhaust or delivery port in the side of the
mixing compartment. An additional oil inlet may be pro-
vided in the mixing compartment to add further oil to the
mixture to create a two-step emulsification process between
the oil and water.
It is accordingly an object of the present inven-
tion to provide a process and apparatus for mechanically
mixing two immiscible liquids and one or more other sub-
stances.
It is a further object of the present invention toprovide a process and apparatus for the continuous mechanical
mixing of disparate substances such as oil, water, gas and
fine particulate matter.
It is a particular object of the present invention
to provide a process and apparatus for producing emulsion
fuel and colloid fuel in emulsion without the use of an
emulsifying agent.
Other objects, features and advantages of the
present invention will be readily appreciated by those
skilled in the art upon consideration of the following
detailed description taken in connection with the accom-
panying drawings.
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BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a sectional view in elevation of a con
tinuous flow jet mixer in accordance with the present inven-
tion.
Fig~ 2 is a sectional view taken along the lines
II-II in Fig. 1.
Fig. 3 is a sectional view taken along the lines
III-III in Fig. 1.
, .
DETAILED DESCRIPTION OF THE INVENTION
A mixing apparatus in accordance with the present
invention is shown in Pig~ 1. The upper section of the mix-
ing apparatus comprises an upstanding cylindrical vessel of
tank 8 with upper and lower concentrically apertured end
walls 8a, 8b and containing a concentrically arranged in-
verted truncated o~erflow cone 9~ A feed pipe 4 extends
through the aperture or opening in the upper wall 8a of tank
8 into the upper portion of overfiow cone 9 and acts as a
flow chute or inlet for the inflow of gas, liquid, powder
or other material in a downward jet. Directly beneath pipe
4 at a level below the upper edge 9a of the overflow cone 9
is a spreader cone 10 secured to the upper end of an axially
disposed rotary shaft 20. Shaft 20 extends through the
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1063597
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lower section of the apparatus and has a pulley 19 on its
lower end by means of which it is driven in rotation through
a belt 18 and pulley 17 connected to a drive motor M mounted
on the mixing apparatus support frame 21. The opening in
the lower wall 8b of tank 8 communicates the lower po.rtion
of overflow cone 9 with thé lower section of the apparatus
which comprises a cylindrical mixing compartment 16.
The mixing compartment 16 contains a mixing disk
11 which is mounted for rotation with the shaft 20 and has
a larger diameter than the opening in the lower wall 8b of
tank 8, which opening is disposed immediately above it. A
plurality of short pins 12 are fixed on the upper surface
of the mixing disk 11 in circular arrays and project upwardly
into the space between the disk and the lower wall 8b of the
tank 8. A plurality of similar short pins 13 are fixed on
the lower wall 8b of tank 8 in circular arrays at different
radial spacings from the pins 12 (see Fig. 2) and project
downwardly from the lower wall 8b to substantially intermesh
with the.pins 12 in the space above the upper surface of
:.~ 20 mixing disk 11. Scraper blades 14 and 15 are fixed circum-
.. l ferentially to the underside of the mixing disk 11 for rota-
tion therewith and the mixing compartment 16 is provided with
. an exhaust or dellvery port 7.
In operation, the inlet pipe 4 conducts a flow of
: one or more substances to be mixed downwardly into the inter-
ior of tank 8, which flow impinges upon the upper surface of
spreader cone 10. The impinging substance or material is
centrifugally dispersed by the rotating cone 10 into the
.liquid film flowing downwardly on the interior surface of
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1063~97
overflow cone 9. The liquid film with the other material
dispersed therein then passes into the mixing compartment 16
for subsequent mixing by the shearing action of the mixing
disk 11 and its cooperating pin structure. The resulting `~
mixture is then passed, with the help of scraper blades 14
and 15, out through the exhaust or delivery port 7.
It will be seen that the above-described structure
and operation incorporates many essential features of the
mixing apparatuses disclosed in U.S. Patent No. 3,871,625
issued on March 18, 1975 to Hiroyuki Iwako and U.S. Patent No.
3,998,433 issued on December 21, 1976 to the same Iwako, one
of the co-inventors of the present invention.
Unlike the previously-disclosed mixing apparatuses,
however, the cylindrical tank 8 of the present invention is
provided with two inlets 1 and 2 to permit the continuous
feeding of two different immiscible liquids, such as oil and
water, each at a constant feed rate into the chamber in the
interior of tank 8. Inlets 1 and 2 are preferably tangential
so that the two liquids, flowing into the tank chamber tan-
.. :~ .. .
gentially, circulate about the outer surface of the inverted
overflow cone 9 and rise in level to the upper edge or rim
. :
9a of cone 9. Upon reaching the level of the cone rim, the
liquids flow over it and move over the inner surface of the
cone 9 in a descending flow creating a continuous liquid
film on the inner surface which passes downwardly through
the central opening at the base of the cone 9. The form and s
thickness of the liquid film will be a function of the qual-
ities of the materials to be mixed and can be determined by
5;
~; the skilled artisan using known factors. Similarly, the
respective flow rates may be controlled to maintain a con-
tinuous film-like flow of the liquids. As the liquids are
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1063S97
immiscible, with proper control the film may be formed of
two layers. If, for example, oil is fed through inlet 1
and water through inlet 2 at the proper rates, the liquid
film will comprise two layers, a layer of water against the
inner surface of cone 9, and a layer of oil over the water
layer. For best results, individual metering pumps (la, 2a)
are used to continuously feed the oil or other immiscible
liquid through inlet 1 and to feed the water through inlet 2
It will be seen that in order to create and sustain a con-
~ tinuous dual-layer liquid film on the internal surface of
the overflow cone 9, the tank 8 is preferably first filled
with water to near the rim of the overflow cone 9 prior to
the subsequent simultaneous operation of-the metering pumps
for the water and oil.
Further, in accordance with the present invention,
the feed pipe 4 is provided with a plurality of inlets, for
example a gas inlet pipe 5, and an inlet pipe 6 for the
introduction of particulate matter, typically fine solid
powders such as pulverized coal, stabilizer, or the like.
aa The powders may be continuously fed into the induced gas
stream, typically air, from inlet 5. The gas-powder mixture
will accordingly be fed to the spreader cone 10 through feed
; chute 4 for subsequent dispersion and mixing into the liquid
film flowing downwardly on the inner surface of the overflow
cone 9.
~ The inlet pipe 5 for introducing the gas or air
; into feed pipe 4 is preferably connected tangentially to
pipe 4, as shown in Fig. 3, to pFovide a circular flow of
., .
gas which will tend to mix with the powder or particulate ~
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:: 1063~97
matter introduced from inlet pipe 6. The downward flowing
mixture of gas and particles impinges upon the surface of
the rotating spreader cone 10 which will impart a centrifugal
force to the mixture that may already possess substantial
energy by reason of being discharged downwardly in a circu-
lating stream through inlet 4. The kinetic energy of the
whirling powder particles aids in their intermixture with
and dissolving into the dual-layer liquid film. As the mix-
ture of liquid, gas, and solids descends onto the rotating
10 mixing disk 11, centrifugal force expels the mixture through
the pin arrays, 12 and 13, effecting a second phase of inter-
mixture and dissolving. Also in the process the mixture is
emulsified by the shearing action of the cooperating pins.
The speed of rotation of shaft 20, and thereby of cone 10
and disk 11, may be adjusted to provide optimum mixing and
emulsifying actions for the various substances used with the
process, as will be understood by those skilled in the art.
A further feature of the present invention involves
~ the incorporation of a secondary oil inlet 3 in the mixing
i 20 compartment 16 for feeding further oil to the emulsion in s
the chamber of the mixing compartment. The oil or other
immisclble liquid is preferably divided into two supplies
to further the emulsification so that a second oil stream
.; lS supplied through inlet 3 into the mixing chamber 16. The
feed rates of the oil in the two supplies depends on the feed
rate of the water, desired emulsion type and other physical
and chemical factors as will be familiar to the artisan.
With this arrangement the first supply of oil through inlet
1 is emulslfied with the water, gas and solids before being
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1063597
mixed with the second supply of oil througn inlet 3 and a
more stable emulsion is ultimately produced. As a result,
the apparatus is able to continuously and mechanically pro-
. duce an emulsion or emulsified particulate suspension very
simply and effectively and wit~out the use of an emulsifying
agent, which has been the conventional means for emulsifi-
cation in the prior art. In the mixing compartment 16 the
mixture of liquid, gas and solids is subjected to a shearing
force caused by the relative movement of the pins 12 and 13,
1~ and the mixture is discharged from the chamber through outlet
: or delivery port 7 by the action of the scrapers 14 and 15.
EXAMPLE 1
Using.the present mixing apparatus an extremely
. stable emulsion comprising 70 parts oil and 30 parts water
by weight with suspended droplets of.less than 3 micron
diameter has been continuously produced with no emulsifying
agent by feeding 30 parts of water through inlet 2 at the . -
rate of 150 kg/hr.and appropriate portions of oil through
inlets 1 and 3 at the respective rates of 135 and 215 kg/hr. ~ :
~ This emulsion remained stable for several months at room
temperature..
EXAMPLE.2
~ .
....................... Using the mixing apparatus of the present inven- .
tion a stabilized colloid fuel in emulsion has been contin-
uously produced by feeding 40 parts o~ oil through inlet 1
: at the rate of 180 kg/hr, 20 parts of water through inlet 2 .
at 90 kg/hr, and 40 parts of pulverized coal through.inlet
. 6 at 180 kg/hr: The coal was continuousl~ dispersed into
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the airflow from inlet 5, which dispersion was subsequently
dispersed into the dual-layer liquld film of oil and water.
This emulsion also remained stable for several months at
room temperature.
Thus, the apparatus and process of the present
invention facilitates the mixing and emulsifying of suitable
substances in the liquid, gaseous and particulate phases to
produce, in appropriate cases, emulsion fuels, or colloid
fuels ln water-oil type emulsions by using mechanical means
obviating the use of emulsifying agents.
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