Vertically moving horizontal mixer assembly with high efficiency blade and stator design

Abstract

A vertically moving horizontal mixer assembly which includes a tank having an axis. A stator and blade support assembly is movable parallel to the tank axis. At least one rotatable blade substantially perpendicular to the tank axis is moveable parallel to the tank axis. The rotating blade may be a flat circular disk with raised tooth edges perpendicular to the disk around the circumference of the blade. An optional stator also directs and encourages movement and mixing of solids with liquids.

Claims

1. A horizontal mixer assembly, which comprises: a tank having an axis; a hub parallel to said tank axis; and a rotating blade perpendicular to said tank axis, said blade being a flat circular disk with raised tooth edges perpendicular to said disk around a circumference of said blade, wherein said raised tooth edges have shoulderless serrations and wherein said raised tooth edges are slightly higher at a trailing edge than at a leading edge and including a plurality of serrated edge openings through said flat circular disk between said circumference and the center of said disk.

2. The horizontal mixer assembly as set forth in claim 1 wherein said plurality of serrated edge openings are of more than one size.

3. The horizontal mixer assembly as set forth in claim 2 wherein said plurality of serrated edge openings of more than one size are circular.

4. The horizontal mixer assembly as set forth in claim 2 wherein said plurality of serrated edge openings of more than one size are trapezoidal.

5. The horizontal mixer assembly as set forth in claim 4 wherein said trapezoidal openings include louvers or tabs extending from the flat circular disk.

6. The horizontal mixer assembly as set forth in claim 1 wherein said raised tooth edges are not tangential to said circumference of said disk but are angled therefrom.

7. The horizontal mixer assembly as set forth in claim 1 wherein said raised tooth edges extend perpendicular to said disk in either direction.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 illustrates a perspective view and

(2) FIG. 2 illustrates a partial cut-away view of a preferred embodiment of a vertically moving horizontal mixer assembly constructed in accordance with the present invention;

(3) FIG. 3 illustrates a sectional view taken along section line 3-3 of FIG. 2;

(4) FIG. 4 illustrates a portion of the mixer assembly with the tank removed for clarity;

(5) FIG. 5 illustrates a perspective view of a portion of the mixer assembly with the tank removed for clarity;

(6) FIG. 6 shows a front view,

(7) FIG. 7 shows a rear view and

(8) FIG. 8 shows a perspective view of one configuration of a rotating blade of the present invention;

(9) FIG. 9 illustrates an alternate embodiment of a vertically moving horizontal mixer assembly in accordance with the present invention; and

(10) FIG. 10 illustrates a further alternate embodiment of a vertically moving horizontal mixer assembly in accordance with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(11) The embodiments discussed herein are merely illustrative of specific manners in which to make and use the invention and are not to be interpreted as limiting the scope of the instant invention.

(12) While the invention has been described with a certain degree of particularity, it is to be noted that many modifications may be made in the details of the invention's construction and the arrangement of its components without departing from the spirit and scope of this disclosure. It is understood that the invention is not limited to the embodiments set forth herein for purposes of exemplification.

(13) Referring to the drawings in detail, FIG. 1 illustrates a perspective view of a vertically moving horizontal mixer assembly 10 constructed in accordance with the present invention. FIG. 2 illustrates a cut away view of the mixer assembly 10 shown in FIG. 1. FIG. 3 illustrates a sectional view taken along section line 3-3 of FIG. 2. The mixer assembly 10 includes a substantially cylindrical tank 12 having a closed base 16 and an optional top. The tank 12 includes an axis 14 (illustrated by dash lines).

(14) The mixer assembly 10 includes a stator and blade support assembly 20. The stator and blade support assembly 20 is movable in alternate directions parallel to axis 14 of the tank as illustrated by arrow 22. As best seen in FIGS. 2 and 3, the stator and blade support assembly 20 includes a pair of spaced apart screw thread shafts 24 and 26. Each of the threaded shafts 24 and 26 is parallel to the tank axis 14. The screw thread shafts 24 and 26 are fixed at their ends to the stator and blade support assembly 20 so that movement of the shafts 24 and 26 results in movement of the stator and blade support assembly 20. A pair of shaft sprockets 28 and 30 has central openings to receive the screw thread shafts 24 and 26 therethrough. Rotation of the sprockets 28 and 30 causes axial movement of the screw thread shafts as shown by arrow 22.

(15) FIG. 4 illustrates a portion of the mixer assembly 10 with the tank 14 removed for clarity. A lift motor 40 has a drive shaft which moves a continuous chain or chains 42 and 44, which in turn rotates the shaft sprockets 28 and 30. It will be appreciated that a belt or belts might be used within the spirit and scope of the invention. Rotation of the sprockets 28 and 30 causes movement of the stator and blade support assembly 20 in a direction parallel to the shaft of the tank axis 14. The lift motor 40 may be secured to the assembly 10 by a lift bracket 46.

(16) As seen in FIGS. 2 and 3, the stator and blade support assembly 20 includes a first pair of blocks 50 and 52 as well as an opposed second pair of blocks 54 and 56. The blocks 50, 52, 54 and 56 travel within notches or channels of parallel I-beams 58 and 60. The I-beams are likewise parallel to the tank axis.

(17) Returning to a consideration of FIG. 4, a blade motor 70 having a drive shaft rotates a blade motor shaft 72. The blade motor shaft 72 extends through the tank 12 and may be supported by a support 74 near the base of the tank 12 (seen in FIGS. 2 and 3). The blade motor shaft 72 passes through and is supported by the stator and blade support assembly 20.

(18) The blade motor shaft 72 rotates a hub 76 which rotates at least one rotating blade 80, which is substantially perpendicular to the tank axis 14. The rotating blade 80 is shown diagrammatically in FIGS. 2 and 3, and will be described in detail herein. It has been found that a single rotating blade 80 is adequate, however, a secondary blade or blades 82 might be employed.

(19) Returning to a consideration of FIGS. 2 and 3 as well as a perspective view of the stator and blade support assembly 20 shown in FIG. 5, an optional stator 84 may take a number of configurations. In a preferred embodiment shown herein, the stator 84 is substantially cylindrical with an upper conical portion. In the preferred embodiment shown, the stator 84 is slightly below the level of the rotating blade 80 although alternate arrangements are possible within the spirit and scope of the present invention. The stator 84 may have smooth internal walls or alternatively may have protrusions, dimples or other disruptive surfaces such as openings or holes which encourage mixing.

(20) FIG. 6 shows a front view, FIG. 7 shows a rear view and FIG. 8 shows a perspective view of one configuration of a rotating blade 80 of the present invention.

(21) The rotating blade 80 includes a flat circular disk 86 with a plurality of raised tooth edges 88 perpendicular to the flat disk 86. The raised tooth edges are generally perpendicular to the flat disk 86.

(22) The rotating blade 80 includes a central opening 90 for attachment to the hub or to the blade motor shaft 72. The raised tooth edges or teeth 88 may be slightly higher at the trailing edge than at the leading edge. A plurality of optional openings 92 may also be provided between the central opening 90 and the outer circumference of the disk 86. In addition, a further set of openings 94 may be in the form of louvers or tabs which encourage movement of materials.

(23) By experimentation, it has been determined that new, surprising and otherwise unexpected results in decreased dissolution times may be obtained by creation and application of the new mixing blade described herein as follows.

(24) Materials used in the experiments were as follows.

(25) 1) Metal containers, 1-quart or 1-gallon, US Friction top style;

(26) 2) Styrene-Butadiene-Styrene (SBS) linear structured tri-block rubber commercially available containing 30% by weight block styrene and commercially known as Kibiton PB-5301 for Chi Mei Corporation, Taiwan;

(27) 3) Suitable heating mantle and controller;

(28) 4) Mixer/Stirrer capable of controlling rotational speed to +/2-rpm;

(29) 5) Test Blades or commercial mixing element 3-inches diameter size; and

(30) 6) Asphalt/Bitumen, PG58-28 grade.

(31) The experimental formulation, expressed to total 100.00% by weight, as follows.

(32) 97.00% Asphalt/Bitumen, PG58-28 commercial product from Flint Hills Resources, MN, USA; and

(33) 3.00% SBS Polymer/Rubber Kibiton PB-5301.

(34) Blade experimental test conditions were as follows.

(35) 1) Heat PG64-22 graded Asphalt/Bitumen in round friction top (US) metal 1-gallon can 2,716.0-grams (97.00% by weight) by suitable means to 180 C. to 183 C. and maintain temperature throughout testing.

(36) 2) Attach test blade (the mixing element) to rotational shaft and lower test blade to 4-centimeter depth as measured from top of liquid to top of test blade and secure by suitable means to mixer.

(37) 3) Set mixer speed for the 3-inch impeller to 600 rotations per minute, 600-rpm (471 feet-per-minute peripheral tip speed) and begin stirring asphalt. NOTE: This creates a tip speed of 471-feet-per-minute, a factor of >10 less than known art teachings.

(38) 4) Mark time Zero (0) and begin addition of 84.00-grams SBS rubber (3.00%) to asphalt being stirred at 600-rpm by mixer and test blade.

(39) 5) Check contents of container periodically for complete dissolution, that is to say melting, of SBS into the mixing asphalt.

(40) 6) When all SBS is melted, note time as Time to Melt in minutes and discontinue mixing.

Experiment No. 0

Known Art Blade

(41) A commercially available of test size blade known as the HSXP model was purchased from Quick Blades, Inc. This mixing blade is characterized by tooth design incorporating a shouldered notch on the top/bottom edge of the tooth. The tooth is also about -inch in width with a tangent angle inward of about 22.5 from the circumference formed by the trailing edge of each tooth. These teeth are about -inch in height. The pumping vanes were pitched so as to cause downward and outward movement of materials. By experimentation as described above, it was found to take 150-minutes for the SBS to melt into the asphalt/bitumen using this blade.

Experiment No. 1

New Art No. 1 Blade

(42) A test blade of which incorporated some of the features of the present invention wherein the serrations were made shoulderless, that is to say have pointed ends and half the diameter of the known art serration. The blade contained 15 teeth in total split between 5 teeth of the same width, -inch, as described in Experiment No. 0Known Art but with serrations made shoulderless as previously described herein and 10 teeth of one-half the width, that is to say -inch wide, of the known art blade and also having shoulder less serrations. This is to say, all teeth of the new art blade of Experiment No. 1 were of the same pitch and angle out from the blade edge but of two different widths. Also note the pumping vanes of the new blade as shown in FIGS. 6, 7 and 8. By experimentation as descried above, it was surprisingly found to take about 105-minutes for the SBS to melt into the asphalt/bitumen using the new art blade.

Experiment No. 2

New Art No. 2 Blade

(43) A test blade which incorporated some of the features of the present invention wherein the pumping vanes of new art blade were replaced with the non-limiting example of 48 round serrated holes. It is within the purview of the art taught herein that many other shapes and sizes of openings are anticipated. In this non-limiting example, these serrated holes were composed of two diameter sizes. One of the hole sizes was -inch and the other size being -inch diameter, respectfully. There were 18 serrated holes of -inch diameter in a pattern of 12 holes around the outer diameter of the blade with 6 holes toward the blade center with the hole centered between the outer hole on either side this hole toward the center. This pattern then forms an outward triangle pattern of the centers of each hole with respect to the center of the blade. There are then 30 serrated holes of -inch diameter inter-dispersed radially and along diameter lines from the blade center. All else remained the same as to blade size, tooth pattern and size as in new art blade. Under experimental conditions as previously described this new art No. 2 Blade melted SBS into the asphalt/bitumen in 65-minutes.

Experiment No. 2E

New Art No. 2 Blade Used to Make Emulsions

(44) The same blade as used in Experiment No. 2 above was used to make an emulsion of asphalt and water. It is known in the art of asphalt or bitumen emulsification that it is more difficult, in terms of power requirements and emulsion stability, to make a water-in-oil (a W/O or inverted) than an oil-in-water (a O/W or regular) emulsion. In this experiment, the New Art No. 2 Blade was used, in the non-limiting example to successfully make the more difficult to form water-in-oil or inverted emulsion.

(45) Emulsion Formulation by Weight Percent

(46) 1.00% Thermogel, a Sepiolite clay from IMV Nevada, known to make water-in-oil emulsions;

(47) 45.00% Water, potable tap water at about 110 F. to 120 F.; and

(48) 54.00% 120/150 pen emulsion base asphalt at about 310 F. to 320 F.

(49) Procedure

(50) 1in 1-quart metal round friction top can add water;

(51) 2Using mixer with speed control and rpm readout, insert New Art No. 2 Blade/shaft assembly;

(52) 3Start mixing at about 200-rpm;

(53) 4Add Thermogel and mix until thoroughly wetted and dispersed;

(54) 5Slowly add by pouring preheated pre weighed asphalt into the water/Thermogel mixture;

(55) 6Gradually increase mixer speed as more asphalt is poured into quart can until all asphalt is added;

(56) 7Continue stirring contents for about 60-seconds; and

(57) 8Discontinue mixing and examine for emulsion formation and stability.

(58) The inverted water-in-oil emulsion was formed at a maximum of 900-rpm wherein the same emulsion with known art blades took more than 3000-rpm to form said emulsion. This is a surprising result in that greatly reduced power requirements, as measured by rotations per minute, were required when the new art blade was used to make an emulsion.

(59) When the above procedure was employed, New Art No. 2 Blade formed the inverted W/O emulsion that was stable (each day examined with no asphalt/water separation and emulsion did not break upon vigorous hand stirring with stainless steel rod) in closed container under heated storage of about 140 F. for more than 3 days.

(60) It is now taught by the non-limiting example above that various emulsions and types of emulsions can be formed by the present invention. Non-limiting examples of emulsion types would be anionic, cationic or non-ionic emulsions of various combinations of oils, liquids and or water with appropriate emulsifiers.

Experiment No. 3

New Art No. 3 Blade

(61) A test blade which incorporated some of the features of the present invention wherein the teeth of new art blade are alternately pitched against each other in an alternating fashion on either side of the blade. Also altering the pumping vanes from new art No. 1 Blade to having serrations about the openings and tabs. Both the openings and tabs are twice the size of those in new art No. 1 Blade and most significantly, reversed in their projection of the materials being mixed. To make more clear, this is to say that the pumping vanes of new art No. 1 Blade project materials outward and downward while in FIG. 6 reference numbers 94a and 94b new art blade projects materials downward and inward at reference number 95a and 95b of FIG. 6. These features are illustrated in FIGS. 6, 7 and 8. Surprisingly, during experimentation, new art No. 3 Blade created excessive splashing wherein this was absent in the previously described new art and known art blades. Therefore, in order to reduce splashing, the rotational speed was reduced from 600-rpm to 400-rpm. Unexpectedly, the time to melt the SBS into the asphalt was the same, 150-minutes, as in Experiment 0,Known Art Blade. This surprising result illustrates the ability of new art No. 3 Blade to be as efficient as Know Art Blade but with lower rotations per minute. It is now obvious to one of average skill in the art that the new art described herein is more efficient than previously known art due to its lower rotation per minute requirement.

(62) Jet StatorsJet mixers are devices composed of a fixed position immovable smooth walled tube (a type of stator) open at the top and bottom that surrounds an impeller. This apparatus was then attached to a vessel wherein mixing is to take place. The jet mixer relies on the ability of the impeller to either pull or push liquid through the smooth walled tube thereby creating the jet mixing action. The impeller or propeller blade(s) is (are) generally shaped so as to scoop or pump, by means of attachment to a rotating high speed fixed length shaft, reasonably close to the interior side of its surrounding stator. The objective of the stator and jet mixer in general, is to provide un-impinged acceleration to the liquid being mixed thereby improving turnover rate of the vessel contents which result in more efficient mixing. In order to limit impingement of the jet mixer stator, the stator generally has as smooth a wall as practical. Further, the impeller or propeller is typically designed to capture as much of the materials being mixed as possible by increasing the surface area of the elements on each impeller. The impeller/propeller is typically fixed in placed at one end or the other of the stator.

(63) Rotor and stator mill combinations are common in mixing applications. The utilities of rotors with their corresponding stators to improve intimate mixing of materials are well understood. The stator itself may have either smooth or not smooth, that is to say textured, wall or surface; especially wherein the stator is of a flat (sometimes called plate) or conical (a cone) configuration. The rotating impeller, commonly called the rotor, is generally of various shapes, sizes and configurations that mate with the stator and rotate at very high speeds under very tight tolerances between itself and the stator, typically being measured in microns. It is common for these mechanical devices to be called Rotor/Stator or Colloid mills or Inline Dispersers.

(64) Typical examples of both the Jet Stator and the Rotor/Stator mills known art are illustrated in the document Mixing and Processing Technology prepared by IKA Works, Inc., of Wilmington, N.C. and included herein by reference. By reference therein, typical of Jet Stators and Rotor/Stator or Colloid mills or Inline Dispersers the impeller and or shaft of the rotor will rotate at about 1,200 or 4,000 or more rotations per minute (rpm or rpm's), respectively.

(65) As a result of the above, current art requires the tip speed of the rotor to be quite high, generally in excess of several thousand feet per minute. To meet the requirement of necessary rotor tip speed, more power through the motor and shaft attachment is a resulting demand.

(66) Stator design as related to jet mixing has always been that of a smooth wall. The examples below illustrate a non-limiting surprising benefit when the interior wall of the jet mixer is either dimpled or perforated. Both the dimpled and perforated walls have a plurality of two sizes. These sizes are -inch and -inch in diameter.

(67) It would be desirable to have a mixing device that would decrease the time required for mixing materials together and yet keep power requirements low.

(68) Unexpectedly, such a mixing assembly has been created by unique combinations of rotor and stator configurations not previously understood by application of either Jet Stator or Rotor and Stator prior art. Such surprising findings are set forth by experimentation below in non-limiting preferred embodiments below.

(69) Materials used in experiments as follows.

(70) 1) Metal containers, Round 5-gallon, US Open top;

(71) 2) Styrene-Butadiene-Styrene (SBS) linear structured tri-block rubber commercially available containing 30% by weight block styrene and commercially known as Kibiton PB-5301 for Chi Mei Corporation, Taiwan;

(72) 3) Suitable heating mantle and controller;

(73) 4) Mixer/Stirrer capable of controlling rotational speed to +/2-rpm;

(74) 5) Known Art Test Blade=3-inches diameter HSXP from Quick Blades, Inc., Huntington, Ind.; and

(75) 6) Asphalt/Bitumen, PG58-28 grade.

(76) The experimental formulation, expressed to total 100.00% by weight, as follows.

(77) 97.00% Asphalt/Bitumen, PG58-28 commercial product from Flint Hills Resources, MN, USA; and

(78) 3.00% SBS Polymer/Rubber Kibiton PB-5301.

(79) Stator experimental test conditions are as follows.

(80) 1) Heat PG64-22 graded Asphalt/Bitumen in round friction top (US) metal 1-gallon can 2,716.0-grams (97.00% by weight) by suitable means to 180 C. to 183 C. and maintain temperature throughout testing.

(81) 2) Stator is 5-inch diameter by 5-inch height (long) at 4-centimeter depth as measured from the top of the liquid to the top of the stator unless otherwise noted.

(82) 3) Unless otherwise noted, the test blade was a 3-inch diameter HSXP model from QuickBlades, Inc., IN, attached to a rotational shaft and lowed to 6-centimeter depth as measured from top of liquid to top of blade and secure by suitable means to mixer head/motor assembly. NOTE: The blade at approximately the center by both diameter and height of the stator, not at the outward end as is known art, thereby leaving a 1-inch gap between the blade tip and stator wall.

(83) 4) Add 284.0-grams SBS (3.00% SBS by weight) to the container.

(84) 5) Set mixer speed for the 3-inch HSXP (or other as noted) to 600 rotations per minute unless otherwise noted and begin stirring asphalt. By calculation, 600-rpm is a 471 feet-per-minute peripheral tip speed. NOTE: This creates a tip speed of 471-feet-per-minute, a factor of >10 less than known art teachings.

(85) 6) Mark time Zero (0) and begin addition of 84.00-grams SBS rubber (3.00%) to asphalt being stirred at 600-rpm by mixer and test blade.

(86) 7) Check contents of container periodically for complete dissolution, that is to say melting, of SBS into the mixing asphalt.

(87) 8) When all SBS is melted, note time as Time to Melt in minutes and discontinue mixing.

(88) While it is known in the art that Cowles or Hockmeyer blades can be used in a closed pipe or tube system, such blades have not previously been shown to have utility in combination with a jet mixer. In general, the Cowles blade relies on high rpm or tip speeds (>5,000 feet-per-minute) to adequately perform. This need for high rpm and tip speed limits their application in terms of tank size. For high speed blades used for dispersion purposed, an explanation of the Dispersion Rules of Thumb may be found in literature from DisperseTech, LLC (E.W. Kaufmann Co. at ewkaufmann.com) or through E.W. Kaufmann Company and now included herein by reference. Following the general rule of the blade diameter should be one-third () the tank diameter would mean that a 21-foot tank would need an exceedingly large 7-foot diameter Cowles blade to perform adequate mixing. Commercially available Cowles blades are typically no more than about 36-inches in diameter which would require 425 to 637 rpm (4000 to 6000 ft/min tip speed) which would or could only mix a tank of about 9-ft diameter by 6-ft in height. Therefore, for one of average skill in the art, the use of high speed dispersion blades would be impractical. Prior to the enclosed art, Cowles blades have not been shown to have utility while combined with a jet mixer. The non-limiting examples below comprise to teach new art applications of Cowles type blades in combination with jet mixing to decrease melt times thereby improving process efficiency. Further, such present invention is now shown to be adjustable to the fluid level in the tank wherein mixing is occurring.

Experiment No. 4

New Art by Known Art Blade without Stator

(89) Using the known art HSXP high shear blade and no stator in container and under conditions described above the time to melt the SBS into the asphalt was found to be 255-minutes.

Experiment No. 5

New Art Application of Known Art Blade with Smooth Wall Jet Stator

(90) In this experiment the smooth wall jet stator, shown in the drawings, was placed in the container as described above and under conditions described above. This Experiment No. 5 differs from Experiment No. 4 by the addition of the smooth wall stator. The time to melt the SBS into the asphalt was found to be 165-minutes. This is quite unexpected and surprising in respect to the low rpm requirements and a blade not typically designed for jet mixing applications. The results are also surprising in that there was excessive splashing of the contents of the container. Such splashing is known to be detrimental to the final product due to the excessive aeration of the asphalt as the SBS melted. Excessive aeration is known to oxidize asphalt that in turn makes the product more brittle in colder conditions. It is, in general desirable to avoid aeration of asphalt.

Experiment No. 6

New Art by Known Art Blade with Dimples in Wall of Jet Stator

(91) Under above described conditions the stator had two sizes of dimples. Those dimple sizes were -inch and -inch in diameter and at a depth of no more than -inch, on -inch centers respectfully, having about a 1/32-inch shoulder as shown in FIGS. 6, 7 and 8. The surprising results of the experiment yield the time to melt the SBS into the asphalt at 150-minutes. This is an unexpected decrease in time over the smooth wall jet stator of Experiment 5 above.

Experiment No. 7

New Art by Known Art Blade with Holes in Wall of Jet Stator

(92) In this experiment, the stator had two sizes of holes. The sizes for the holes were -inch and -inch in diameter. The blade, as described above, and stator described herein were raised to 4-inches and 2-inches, respectfully in order to facilitate liquid/solids surface movement and mixing of the container contents. Under the conditions as noted herein the melt time of the SBS into the asphalt was found to be 150-minutes. The unexpected results of raising the blade and stator in unison yields the same SBS melt time as in Experiment No. 6 thereby illustrating the utility of need for the artisan to raise and or lower the unit or its component parts, blade or stator, to advantageously effect process results. Therefore a mechanism for moving the blade and or stator would be a desirable advancement of the art. In comparing this Experiment No. 7 to Experiment No. 5 the difference is a stator with holes verses a stator that is smooth walled, respectfully. With respect to these differences, the stator having a plurality of holes did not splash or aerate the asphalt as the SBS was melting into the mixture. This feature of not splashing would offer the potential for a better quality final product, especially with respect to being not as brittle under colder conditions verses a similar product as made under conditions as set forth in Experiment No. 6.

(93) From the above examples it is now taught herein that other types of modifications to the jet mixer may prove advantageous to specific applications. Non-limiting examples of such modifications to the jet mixer stator wall could be grooves of various size, width, depth or shape. Said grooves may be somewhat square, rectangular, U or V shaped. Said grooves might also be essentially shoulder less or otherwise have no space between each individual groove thereby forming serrations or edges; non limiting pattern of W for example. Said grooves, that might also be called channels, may extend up and down, across at an angle or otherwise be shaped to aid in a given mixing application. The unexpected results of raising the blade and stator in unison yields the same SBS melt time and decrease unwanted splashing of container contents as in Experiment No. 7 verses Experiment No. 8, above, thereby illustrating the utility of need for the artisan to raise and or lower or otherwise adjust the unit or its component parts, blade or stator, to advantageously effect process results. Therefore a mechanism for moving the blade and or stator would be a desirable advancement of the art. In comparing this Experiment No. 7 to Experiment No. 5 the difference is a stator with holes verses a stator that is smooth walled, respectfully. With respect to these differences, the stator having a plurality of holes did not splash or aerate the asphalt as the SBS was melting into the mixture. This feature of not splashing would offer the potential for a better quality final product, especially in with respect to being not as brittle under colder conditions verses a similar product as made under conditions as set forth in Experiment No. 6.

(94) As an alternate embodiment, FIG. 9 illustrates a mechanism to mix and disperse solids in a liquid. The assembly 80 includes a center shaft 82 which will be rotated in a direction shown by arrows 84. The shaft 82 may be non-circular. In the embodiment shown in FIG. 9, the shaft includes a recess which receives a key on a drive plate 86. The disk 86 is driven by a right hand gear 88 which, would in turn, be connected to a motor (not shown). Accordingly, rotation of the drive gear 88 would rotate the disk 86 which, in turn, would rotate the shaft 82. A pair of hubs 90 and 92 surround the shaft but are not rigidly attached thereto. A plurality of blades 94 and 96, respectively, extend from each of the hubs (partially cut away in FIG. 9). Each hub 90 and 92 also has an extending key that mates with the slot in the shaft 82. Accordingly, rotation of the shaft rotates the hub and, in turn, each of the blades.

(95) A mechanism is provided to move each of the hub and blade assemblies vertically or axially in the direction shown by arrows 100 and 102.

(96) The mechanism is provided to move the hub 90 and its blades 94 and move the hub 92 and its blades 96 vertically in the direction shown by arrows 100 and 102. A threaded screw drive 106 extends parallel to and spaced from the axis of the shaft 82. The threaded screw drive 106 engages hub 90 at a threaded opening 108. As the screw drive 106 is rotated in one direction, the engagement with the threaded opening 108 causes the hub 90 and propellers 94 to move axially or vertically in a first direction while rotation of the screw drive in a second direction will cause the hub and propellers to move axially or vertically in the opposite direction. Likewise, threaded screw drive 112 extends parallel to and spaced from the axis of the shaft 82. The threaded screw drive 112 engages the hub 92 at a threaded opening 114 therethrough. The screw drive 112 may be rotated in the direction shown by arrows 116 and 118. Accordingly, as the screw drive 112 is rotated in a first direction, the engagement with the threaded opening 114 will cause the hub and the propellers to move axially or vertically in a first direction while rotation of the screw drive 112 in a second direction will cause the hub and propellers to move axially or vertically in the opposite direction.

(97) The hub and propeller assembly 80 may also include a rotating disk 120 which rotates with rotation of the shaft. The disk 120 is engaged with stationary disk 122 with a bushing 124 therebetween. The stationary disk 122 may be attached to the top of a tank (not shown), making the assembly easy and simple to retrofit to an existing tank.

(98) FIG. 10 illustrates a perspective view of a further, preferred embodiment. The assembly 130 includes a shaft 132 which is rotatable in the direction shown by arrows 134. The shaft is rotated by means of a right hand gear 136 connected to a motor (not shown). The right hand gear 136 engages a drive hub 138 having external angled gears to match the gears on the right hand gear 136. Accordingly, rotation of the right hand gear 136 rotates the hub 138 which, in turn, rotates the shaft. The hub and prop assembly 130 may include a first hub 140 and a second hub 142 spaced therefrom. The first hub is rotatable in the direction shown by arrows 144 while the second hub is rotatable in the direction shown by arrows 146. Each of the hubs 140 and 142 surrounds the shaft 132 but is not rigidly attached thereto. Extending from hub 140 is a set of blades 148 while extending from hub 142 is a set of blades 150.

(99) A mechanism is provided to move the hubs and the blades vertically or axially in the direction shown by arrows 152. A portion of the shaft 132 includes a set of teeth 154. A drive gear 156 may be brought into engagement with the teeth 154. Rotation of the drive gear 156 will cause axial or vertical movement of the shaft 132 in the direction or directions shown by arrow 158. Accordingly, axial or vertical movement of the shaft 132 results in corresponding movement of the hubs 140 and 142 and the blades 148 and 150, respectively.

(100) In addition to the foregoing, the teachings of the present invention may be combined with the teachings of Applicant's U.S. Pat. No. 5,938,326 entitled Combination Dispersion And Skimming Device.

(101) Whereas, the present invention has been described in relation to the drawings attached hereto, it should be understood that other and further modifications, apart from those shown or suggested herein, may be made within the spirit and scope of this invention.