ultrasonic fuel water emulsifier eric cottell

8/8/2019 Ultrasonic Fuel Water Emulsifier Eric Cottell

1/28

Eric COTTELL

Ultrasonic Fuel-Water Emulsifier

Newsweek(June 17, 1974): "A Solution to Air Pollution" John F. Pearson:Popular Mechanics (November 1972); "A Furnace That Burns

Water"Eric C. Cottell: US Patent # 3,749,318 ~ "Combustion Method and Apparatus Burning

an Intimate Emulsion of Fuel & Water" E. Cottell: US Patent # US Patent # 3,941,552 ~ "Burning Water-in-Oil Emulsion

Containing Pulverized Coal"E. Cottell: US Patent # 4,048,963 ~ "Combustion Method Comprising Burning anIntimate Emulsion of Fuel and Water"Patents by E. Cottell @ Espacenet (European Patent Office)

Newsweek(June 17, 1974)

A Solution to Air Pollution

In the wake of the energy-crisis a 50-year-old British-born inventor named Eric Cottell hascome up with an ingeniously simple and economically practical solution -- one that is nowexciting industry and government officials alike.

In the conventional combustion process, fuel is combined with air and turned. The result iscarbon dioxide, water vapor and heavy oxides of nitrogen, which are a prime cause ofchemical smog. Cottell reasoned that if water could largely replace air as a source of oxygenin combustion, this would avoid the large amounts of nitrogen introduced by the air -- andthus eliminate much of the noxious nitrogen oxides.

To accomplish this, he turned to a device he had patented 22 years ago -- an ultrasonic reactorthat emulsifies heavy liquids and is widely used today to prepare such products asWorcestershire sauce, ketchup, cosmetics and paint. By refining the reactor, Cottell was ableto break water into particles about one fifty-thousandth of an inch in diameter and to dispersethem evenly in oil (or gasoline) to create an emulsion that was 70 percent oil and 30 percentwater. When this emulsion was burned, Cottell found :

(1) that there were far fewer waste products and

(2) that the small water droplets expand on heating, then explode into steam, in turn shatteringthe oil into even finer particles, and thus increasing the surface area of the fuel exposed for

burning.


2/28

Last month Cottell divided his time between Washington, in talks with officials of the FederalEnergy Office, and Detroit, where he consulted with engineers working to meet the tight 1976automobile-emission requirements. So far, auto tests have shown that with an ultrasonicreactor attached to a carburetor, a car can get almost DOUBLE the normal miles per gallon ofgasolinge -- with neglible exhausts. Cottell's company, Tymponic Corp. ofLong Island, N.Y.,is also about to produce units for home oil burners that will be no larger than a flashlight and

cost $100 to $150.

Last winter, two Long Island schools converted to Cottell's system, and both reduced theirfuel usage by about 25%. Adelphi University reports that it saved more than 3,500 gallons ofoil per week! -- and reduced soot output by 98 %."

Popular Mechanics (November 1972)

"A Furnace That Burns Water"

by John F. Pearson

A revolutionary combustion system makes it possible to burn emulsions of fuel and water. It

works in a car engine as well as an oil furnace and cuts pollutants, too.

Its impossible. An oil burner simply cant run on a fuel that is one-third water -- tap water, atthat. But I recently saw it done.

The demonstration was at the Bayville, NY home of Eric C. Cottell, a British-born engineer

and inventor. The gadget that made the "impossible" happen is a Cottell invention called theUltrasonic Reactor -- a device resembling a long, slim electric motor. It contains a crystalstack at one end and a mixing chamber at the other.

When a 60-cycle current is applied, the crystals vibrate at 20,000 cycles per second, turning

the reactor into a "super-blender". As shown in the diagram, oil and water (70% oil, 30%water) flow into the reactor, where a terrific vibrating force causes water and oil molecules torupture. The two liquids form an emulsion in which tiny particles of water are dispersedthroughout the oil. When this happens, says the inventor, the surface area of the water isincreased millions of times. Thus, when the emulsion hits the furnaces combustion chamber,the water "explodes" into superheated steam, adding to the energy ouput of the oil.

In hundreds of tests of his system, Cottell has found that ordinary boilers run at efficienciesclose to 100% -- as astounding result that neither he nor leading combustion experts canexplain. In the demonstration I saw, gauges indicated that the emulsion produced the sameamount of heat as a 100% oil fuel.

In addition to stretching fuel, the system reportedly produces fewer pollutants than standardoil combustion. The fact that one-third less oil is burned is a key anti-pollution factor.


3/28

Though Cottell sees many potential applications for the reactor -- in auto, ship and planeengines, for example -- he thinks the best immediate application is in heating plants of largeapartment buildings.

"This is by far my most exciting invention", says Cottell, who holds patents in the fields ofultrasonics, hydraulics, and chemistry.

US Patent # 3, 749,318

( US Cl. 239/102 ~ July 31, 1973 )

Combustion Method and Apparatus Burning an Intimate Emulsion of Fuel

and Water

Eric C. Cottell

Abstract --- A combustion apparatus and process in which a water-in-oil emulsion of liquidfuel, such as liquid hydrocarbons, containing from 10 to 50 % water, the emulsion being

produced without any substantial emulsifying agent and preferably by sonic agitation, isburned.

The combustion of liquid fuel, such as liquid hydrocarbons, is a standard method of power

and/or heat generation. The combustion may be in a system where the heat is transferred toanother medium, such as water, with or without boiling the water, or the fuel may be burned

in various types of internal combustion engines, such as those operating on Otto, diesel, orother cycle. The amount of oxygen, usually air, is at least about theoretically sufficient for

complete combustion of the fuel elements.

Considerable problems have arisen. If there is a very large excess of oxygen, the efficiency ofthe combustion process is lowered because a considerable amount of the air, including inertnitrogen, has to be heated up. In the case of an internal combustion engine, operating withexcessive amounts of oxygen can result in slow combustion, which can overheat and burn outexhaust valves. If the combustion is with amounts of oxygen and fuel more nearly in balance,for example with only a small excess of oxygen, problems arise with incomplete combustion.This can result in excessive amount of carbon monoxide and/or incompletely burned fuel,which may show up as unburned hydrocarbons, soot and the like. Incomplete combustionlowers the combustion efficiency and can also contaminate the equipment. In the case ofinternal combustion engines, unburned hydrocarbons, carbon monoxide, and oxides ofnitrogen, generally symbolized by the formula NOx, are serious atmospheric pollutants as

they give rise to photochemical smog and the like. Contamination of NOx from an IC engineusually results when combustion temperature is high.

It has been proposed in the past to introduce streams of water into a burner or to inject waterinto an internal combustion engine as it operates. This has proven to reduce somewhatincompletely burned fuel deposited in the form of carbon, and in the case of IC engines thiscan lower NOx production and also in certain cases, such as aircraft piston engines, permitoperating for short times at higher power outputs with very rich mixtures which wouldotherwise burn up the engine. Water injection, however, has serious drawbacks. In the first


4/28

place, it is very difficult to control relative amounts of water and fuel precisely. Even if thecontrol is maintained to a satisfactory degree, efficiency drops because the water has to bevaporized, with its extremely high latent heat, and heated up in the combustion, which takesfurther power because of the high specific heat of water vapor. As a result, water injection hasonly bee practically used in unusual circumstances.

Summary of the Invention

The present invention burns an extremely fine emulsion of water and liquid fuel, normallyhydrocarbonaceous fuel, in which the water droplets are dispersed in an extremely fineaverage particle size. While the present invention is not absolutely limited to the method bywhich the emulsion is carried out, it is preferred to emulsify by using an ultrasonic probe orother device which agitates the fuel and water to produce an extraordinarily finely dispersedemulsion, because it is the fine dispersion that produces the important new results which will

be set out below; mere presence of the water does not.

According to the present invention, if a very fine emulsion is burned, which may have fromabout 10% to as much as 50% water, extremely clean combustion results, contamination and

pollution are minimized, and in a straight atmospheric burner up to 30% of water will giveresults in which the heat obtained by the combustion is substantially the same as if allhydrocarbon fuel were burned. In other words, with 70% fuel and 30% water, the emulsionwill produce the same amount of heating. This surprising result has been repeatedly tested,and while I do not want to limit the present invention to any particular theory, it seems

probable that the combustion of the emulsion is so complete that the smaller amount of fuel iscompletely burned and the same final heat is obtained as if there were no water present. Theabove statements are made with respect to a system in which the surfaces which are heatedare at a sufficiently high temperature so that water vapor does not condense. In other words,no part of the new result is due to condensation of water vapor on cooler surfaces. In the caseof the application to an IC engine, not only are the surfaces hot but the exhaust gases leave theengine cylinder greatly above the condensation point of water vapor.

In the IC engine modification of the present invention, while the total amount of power maybe as great or, under certain circumstances, even greater, the peak flame temperature isusually lower, and it seems probable that the reduced emission of NOx results primarily fromthis factor. However, this is not known, and the water vapor present in larger amounts ascompared to carbon dioxide may also play a part. Therefore, it is not intended to limit theinvention to any particular theory, and the above statements are made because I think thefactors mentioned are at least some, and conceivably the only, factors involved.

The invention is not limited to the time in the whole operation when the very fine water-in-oilemulsion is actually produced. This may be at the point where atomization takes place just

prior or at the point of ignition. This, however, is not necessary, and the emulsion may beperformed and conveyed to the burner nozzle in a preformed state. Particularly with thereferred emulsions obtained by sonic agitation, the emulsion is quite stable and so it can be

produced at a point remote from the actual burner itself, and such a modification is of courseincluded. It is also possible to have the emulsion formed by flowing water and oil over theemulsifying point, so that the emulsion is formed at the same place, or practically at the same

place, as atomization into the flame takes place. In the case of the use of sonic atomization,particularly for IC engine use, it is almost always preferable to have the streams of water andfuel unite just prior to the point of atomization. It is possible, of course, to feed to the sonic


5/28

atomizer an already formed emulsion, but this requires a separate step and the results are notsignificantly better. Therefore, particularly in the case of sonic atomization for combustion,and even more particularly in the case of IC engines, it is generally preferred to have theemulsion formed at the point and as a part of the atomization or atomizing device.

It is an important advantage of the present invention that it is not necessary to use any

emulsifying agent, particularly when sonic emulsification is used. This eliminates the addedstep and, therefore, cost of the emulsion is reduced, although in a broader aspect the presentinvention does not exclude an emulsion which has been made in the presence of a smallamount of an emulsifying agent, such as a small amount, usually a fraction of a percent, of adialkyl sulfosuccinate or other well known emulsifying agent capable of facilitating theformation of water-in-oil emulsions. The invention in this aspect, which is normally not

preferred, may use any known emulsifying agent.

Ordinarily more problems are presented with the burning of heavy residual fuel oil, and thisfrequently requires steam heating. In the case of the present invention, however, the heavy oilemulsifies more readily than light oil, and when emulsified with a considerable amount ofwater, the viscosity is low enough so that it can be burned without preheating. This is an

additional advantage for use with heavier oils. Why the heavy oil emulsifies more readily andto a lower viscosity has not been fully determined. It is possible that the heavy fuel oilcontains contaminants which aid in the emulsification which are not present in the purerlighter fuel oils. It is not intended, however, to limit the present invention to any theory ofaction.

While, as has been stated, the invention is not limited to any particular method, sonicemulsification is greatly preferred. It produces emulsions of maximum fineness at very lowcosts, and so in one further aspect of the invention there is included the combination offorming ultrasonically a fine water-in-oil emulsion and then introducing this into a burner.

Brief Description of the Drawings

Figure 1 shows, in diagrammatic form, a sonic emulsifier and burner;

Figure 2 is a detail on a somewhat enlarged scale, partly in section, of the emulsifier;


6/28

Figure 3 is a semi-diagrammatic illustration of a combined sonic atomizer and emulsifier,especially useful with internal combustion engines;

Figure 4 is an illustration of a unitary emulsifier and furnace burner, particularly for largerunits, and

Figure 5 is a horizontal elevation detail of the expanded plate at the end of the probe.


7/28

Description of the Preferred Embodiments

In Figure 1 a sonic generator 1 is shown powering a sonic probe 2 in the form of an acoustictransformer, the end 9 of which extends into a chamber 3 through a flexible seal 4 locatedsubstantially at a nodal point of the sonic probe. A stream of fuel, such as house heating fueloil, is introduced through a conduit 5 and a stream of water joins it through a conduit 7 with afail safe valve 18 opened by fuel pressure. These two streams strike the vibrating end 9 of the

sonic probe, as can best be seen in Figure 2 where a portion of the chamber 3 is shown insection. The violent sonic agitation emulsifies the two streams, which then leave axiallythrough an outlet conduit 6 in a plate 10 which is located closely adjacent to the vibrating end9 of the sonic probe. Fro the outlet conduit 6 the emulsion passes into a convenient burner 8 ina combustion chamber (not shown). Air is introduced at 20 and a flame results. While the

proportion of fuel and water can vary over a wide range, for example fro about 10 % water toabout 50 % water, a very suitable mixture is about 70 % fuel and 30 % water.

The sonic probe 2 is of conventional design with a stack of piezoelectric plates (not shown),which are energized through cable 12 by a suitable high frequency oscillator (not shown),which may operate, for example, at a frequency of approximately 20,000 Hz. The plate 9 at

the end of the sonic probe 2 may be a flat plate or it may also be provided with a suitable

baffle, for example a spiral baffle, to extend the period of residence in the violent agitationfield. The sonic generator illustrated diagrammatically is of common a commercial type sold

by the Branson Instruments under their trade name Sonifier. The particular design of the sonic

emulsifier ahs nothing to do with the present invention and the illustration shows merely atypical one.

Figures 4 and 5 illustrate a unitary emulsifier and burner for furnace use. The same elementsare given the same reference numbers as in Figures 1 to 3. The end of the Sonifier tip if of thegeneral shape shown in Figure 3m which will be described further below, and the parts bearthe same reference numbers there as in Figure 3. It will be seen tha in Figure 4 there is anoverall housing through which a blast of air passes from the blower 13. This air flows over theultrasonic generator, thus cooling it, which is desirable in a large sized burner, and finally

passes over the end of the housing 15. The fuel and water streams flow into an annular spacebetween the housing 15 and the Sonifier probe. The latter is provided with an end plate 10which has a series of small annular depressions 11 with a central projection 12 forming theinside of the annulus. This can be seen in Figure 5. The clearance between the end of thehousing and the plate 10 is quite narrow and is shown somewhat exaggerated in Figure 4 forthe sake of clarity. A film of fuel and water flows over the plate, where it is emulsified andatomized and thrown some distance to the right, forming a flame, which is diagrammaticallyshown at 19.


8/28

Combustion results in a boiler were measured in relative times to bring the water in the boilerjacket from a particular temperature to a temperature just below its boiling point. The testaccurately measures the relative heating efficiencies and is shown in the following table,which illustrates the results of 8 tests, test 1 to 5 being with straight No. 2 domestic heating oiland tests 6, 7, and 8 with a mixture of 70% oil and 30% water.

Temperature (1) ~ Temperature (2) ~ Time (min) ~ Material1. 150 ~ 192 ~ -- ~ Oil2. 150 ~ 194 ~ 4-13 ~ "3. 146 ~ 194 ~ 4-14 ~ "4. 144 ~ 192 ~ 4-6 ~ "5. 144 ~ 194 ~ 3-40 ~ "6. 146 ~ 194 ~ 3-30 ~ 600 oil/325 water7. 144 ~ 192 ~ 4-20 ~ 850 oil/200 water8. 144 ~ 196 ~ 4-16 ~ 800 oil/250 water

Boiler surfaces were carefully examined in the tests and were clean. A flame was producedwhich was whiter; there was no visible smoke from the chimney, and stack gas analysis

showed a more complete and perfect combustion.

Figure 3 illustrates a modification particularly useful for IC engines. The Sonifier with itsprobe carry the same reference numerals as in Figures 1 and 2, but, as in Figures 4 and 5, theshape of the end of the probe is a little different, being expanded out into a plate 10. The plateis flat instead of provided with annular depressions as in figure 4. Gasoline was introducedthrough the conduit 14 into an annular space between the probe and a housing 15, and waterwas introduced through conduit 13. The two liquids flow down until they come to the edge ofthe expanded plate 10, where they proceed to flow along the top of the plate and are atomizedand emulsified at the same time. Air is introduced adjacent the atomized emulsion through anair conduit 16 and the resulting mixture is fed into the manifold of an internal combustionengine (not shown).

The plate 10 projects beyond the housing, the clearance between housing and Sonifier beingexaggerated as in Figure 4, and the violent sonic agitation of the pate throws a finely dividedemulsion up from the upper surface of its projection. As Figure 3 is designed to connect witha manifold of an IC engine, there will usually be a certain amount of vacuum, and this causesthe emulsion to be pulled around the edge pf the plate, as is shown by the arrows. Thoroughmixing of the air takes place, but it is not necessary that the emulsion be thrown by sonicvibration into the manifold, whereas in Figure 4 with the horizontal burner this is necessary sothat the fine emulsion atomized in the blast of air moves horizontally to form the burnerflame. It is for this reason that the actual contact of the plate with the film of fuel and waterflowing over it is on its forward face so that it will be thrown in the direction to form the

burner flame, for of course in an ordinary burner there is not the vacuum which exists in aninternal combustion engine manifold.

Figures 3 and 4 and 5 illustrate different forms of Sonifier and emulsion forming plate, but theinvention is not limited to the exact shapes shown nor for that matter to the flat tip face asshown in Figure 2. These are simply illustrations of typical configurations, but the inventionis not limited to the details thereof.


9/28

The IC engine fed with a gasoline and water emulsion atomized into the air ran with the samepower as on straight gasoline, and pollutants were reduced, unburned hydrocarbonspractically zero, and NOx still more reduced. The figures illustrate the pollutantconcentrations, the engine running at about 5000 rpm under load. It will be noted that the

pollutant concentrations are far below present emission standards and even meet more rigidstandards proposed for later years. Carbon monoxide 0.94, unburned HC 0.0, NOx 11.35

ppm.

I claim: [ Claims not included here ]

US Patent # 3,941,552

( US Cl. 431/1 ~ March 2, 1976 )

Burning Water-in-Oil Emulsion Containing Pulverized Coal

Eric C. Cottell

Abstract --- Pulverized coal is slurried with water then oil or if desired oil and pulverizedalkalis preferably lime or limestone is added and the mixture subjected to sonic vibrationswith an energy density of at least 11.625 watts per cm.sup.2. Liquid suspension is producedand any excess water or oil separates out as a separate phase. Normally excess oil is used andthe excess oil phase can be recycled. The resulting dispersion is utilized and burned in afurnace. A clean flame is produced which has the characteristics of an oil flame and not a

powdered coal flame. The addition of lime is optional as its purpose is to reduce sulfurdioxide in burning where the coal contains sulfur. If there is no sulfur or so little as to meetenvironmental standards the addition of lime may be omitted. The amount of lime is

preferably at least about twice stoichiometric based on the sulfur content of the coal. Up to80% of sulfur dioxide produced on burning can react with the lime and the calcium sulfateproduced removed by conventional particle separators.

References CitedU.S. Patent Documents3073652 ~ Jan., 1963 ~ Reichl ~ 110/73746257 ~ Jul., 1973 ~ Broad, et al. ~ 239/1023823676 ~ Jul., 1974 ~ Cook, et al. ~ 110/1

Primary Examiner: Favors; Edward G.Attorney, Agent or Firm: Norton; Robert Ames, Leitner; Saul

Description

BACKGROUND OF THE INVENTION

Coal is usually burned either in a bed or if pulverized and atomized in the form of fineparticles. When the coal contains substantial amounts of sulfur this is transformed into oxidesof sulfur, mostly sulfur dioxide, during combustion. Sulfur oxides constitute seriousatmospheric pollutants and in recent years quite stringent standards have been set in the


10/28

United States for the concentration of sulfur oxides which can be vented to the atmosphere.This has required either low sulfur coal, about 1% or less, or the coal can be treated to removeexcessive sulfur. In either case, there is a substantial penalty. It has therefore been proposed tomix finely divided lime or limestone with the coal and during burning a considerable amountof sulfur dioxide is oxidized in the combustion process which always has excess oxygen andcalcium sulfate is produced. The removal of the particulate calcium sulfate can be effected by

conventional means such as electrostatic precipitation. Combustion is not as complete ascould be desired and unless there is a very large excess of lime the amount of sulfur oxidesremoved can be insufficient in the case of high sulfur coals.

It is with an improved coal fuel that the present invention deals and problems such asexplosion hazards in powdered coal plants that are not kept scrupulously clean are avoided.

SUMMARY OF THE INVENTION

In the present invention pulverized coal is used particle sizes below 100.mu. and aconsiderable portion is normally much finer down to as fine as 1.mu.. This is approximatelythe same form of coal used for powdered coal burning. When the tiny coal particles are

examined under a microscope the surface appears quite porous. The pulverized coal is slurriedwith water and then oil is added, such as ordinary heating oil and the slurry is then subjectedto violent sonic agitation. Ordinarily the frequency is in the ultrasonic range, for examplefrom 20,000-30,000 Hz., or even higher frequencies. While in practice frequently ultrasonicagitation is used high sonic frequency for example 15,000-20,000 Hz. can be used, thereforethroughout this specification the generic term "sonic" is used which covers both audible andultrasonic frequencies. It should be realized that intense agitation which produces strongcavitation is necessary and this is measured as intensity and not as power. In the presentinvention the intensity should be at least 11.625 watts per cm.sup.2. Commonly intensities ofaround 38.75 to 54.25 watts per cm.sup.2 or a little less are employed. While there is adefinite lower limit for sonic intensity below which satisfactory fuels will not be produced,there is no sharp upper limit. However there is no significant improvement above 54.25 watts

per cm.sup.2 and higher intensities add to the cost of producing the fuel without resultingimprovement. In other words, the upper limit is not a sharp physical limit but is dictated byeconomics.

So long as the energy density meets the specifications above, it does not make muchdifference how the sonic energy is produced and the present invention is not limited to any

particular apparatus. A very practical sonic generator is a so called sonic or ultrasonic probe.Longitudinal vibrations are produced as conventional, either by piezoelectric,magnetostrictive device or the like. The sonic generator proper is then coupled to a solidvelocity transformer, sometimes called an acoustic transformer, which tapers down,

preferably exponentially, ending in a surface of much smaller area than that coupled to the

sonic generator. In accordance with the law of conservation of energy the distribution of thevibrations over the smaller surface requires that the surface move more rapidly. This results ina much greater energy density andd as the total power is being transformed from a larger areato a smaller area, this is referred to as a transformer by analogy with electrical transformerswhich can step up voltage. Sonic probes of the type described above are commercial productsand sold, for example by Branson Instruments under their trade name of "Sonifier." This typeof apparatus for producing high sonic energy density, which should not be confused withsonic power, is a very economical and satisfactory type of producing the necessary sonicenergy intensity. In a more specific aspect of the present invention the use of this type of


11/28

instrument is included but of course the exact way the vibrating surface is energized is notwhat distinguishes the present invention broadly from the prior art.

The high intensity sonic agitation appears to drive water into the pores of the porous coalparticles and then produces a water-in-oil type of emulsion. This is not a true emulsionbecause it includes suspension of the tiny coal particles as well as a dispersion of oil and

water. However, the behavior of the resulting product which is a somewhat viscous liquid isnot that of a typical emulsion. In a typical water-in-oil emulsion, the continuous oil phase can

be diluted with more oil to produce a more dilute emulsion. In the case of the presentinvention, however, when an excess of oil is used oil separates as a separate phase, in thiscase a supernatant phase. While it is theoretically possible with an exact ratio of coal, waterand oil to produce a product that does not separate out any oil phase as a practical matter thisis undesirable because the separation it too critical and it is much better to operate with asmall excess of oil and separate and recycle the supernatant phase. Although, as has been

pointed out above, the product of the present invention is not technically a water-in-oilemulsion it has some properties that are similar. Thus, for example, after removing a

supernatant oil phase the remaining oil and water remains stable in and around the coalparticles and the product can be stored for a reasonable time without further separation of the

components. For this reason the product will be referred to in the specification as an emulsioneven though technically it is not a true emulsion. It is, however, a dispersion of the coal

particles and tiny water droplets and, as pointed out above, it is stable. When the product orfuel of the present invention is burned it burns very cleanly with a flame of the color andcharacteristics of an oil flame rather than a powdered coal flame. Apparently duringcombustions there is not a physical production of fine coal particles although the exactmechanism of combustion has not been completely determined and the present invention istherefore not intended to be limited to any particular theory.

The exact proportion of coal, water and oil is not critical, which is an advantage. It will vary alittle with the gravity of the oil and with particular coal an excellent practical ratio is about 20

parts of pulverized coal, 15 parts of oil and 10 parts of water. This product settles out only alittle oil as a supernatant liquid and a very stable dispersion results. However, somewhat moreoil may be used and in some cases is desirable because the separated oil phase can easily berecycled, and therefore the above ratio of ingredients is illustrative of a typical useful product.It should be noted that if there is an excess of water this also can separate a portion of water asa separate phase. For practical operation it is usually desirable to have any excess in the formof oil.

The violent sonic agitation also performs an additional function. It reduces the particle size ofthe coal, possibly because of coal particles striking each other during the violent agitation.The exact amount of reduction of particle size depends both on the energy density of the sonicagitation and on the character of the particle coal. A more fragile coal will, of course, be

reduced somewhat more but the final size range still remains between about 1.mu. and about100.mu..

While the dispersion is fairly viscous it still flows readily and does not have to be heated priorto supplying it to the burner. This is an advantage over burning highly viscous residual fueloils which have to be heated by steam before being atomized in a burner. This is one of theadvantages of the present invention as it permits eliminating heating equipment withouteliminating its function.


12/28

The actual atomization in a burner is not what distinguishes the present invention from theprior art and any suitable form of a burner can be used. One such form is a sonic probe whichatomizes the dispersion of fuel from its end.

Where the coal used is of low sulfur so that sulfur oxide emissions from a furnace stack arewithin environmental standards the fuel of the present invention may constitute only

pulverized coal, oil and water, however, the present invention makes possible elimination of alarge amount of sulfur oxides in a very simple and economical manner. This opens up cheap,high sulfur coal for use where it would otherwise not meet environmental standards. When itis desired to reduce sulfur oxide emissions preferably finely pulverized lime or limestone may

be dispersed in the water. This will be generally referred to as lime and it may be introducedin the process of the present invention either before or after oil introduction, preferably it isintroduced substantially simultaneously when feeding to the sonic emulsifier. It should benoted ordinarily pulverized lime will be fed in in the form of a water slurry and the watercontent must be taken into consideration in the total amounts of water in the final product.When the pulverized lime is introduced it forms part of the suspension and is stable and does

not settle out on standing. This avoids any distinct problems and is a further advantage of theaspect of the present invention where sulfur oxides are decreased.

Lime is the preferred alkali to use when high sulfur coal is to be burned. It has many practicaladvantages such as low cost and the fact that the calcium sulfate which is produced in theflame has very low solubility in water. Other alkalis may be used such as for example sodiumcarbonate. Most of these other alkalis form sulfates which have considerable solubility inwater. As water vapor is always produced in the burning of the fuel this can present problems

particularly as at some stage of the stack gas treatment temperatures are reduced and liquidwater may condense out. In such a case it can form somewhat pasty masses with alkalis, thesulfates of which are fairly soluble in water. This makes electrostatic precipitation moredifficult, as the precipitator normally requires that the particles which it removes be dry.There is also a possibility in other parts of the combustion gas treatment equipment fordeposition of pasty sulfates to result. This requires additional cost for cleaning and is one ofthe reasons why lime is the preferred alkali. However, other alkalis may be used and in its

broadest aspect the invention is not limited to the use of lime although this is the preferredmaterial.

The removal of sulfur oxides depends on the amount of lime or other alkali. The lime shouldnormally be in excess over the stoichiometric value based on the sulfur content of the coal.The more lime used the greater reduction. For example with a 50% excess 50% of the sulfuroxides may be eliminated or rather fixed as calcium sulfate. When more lime is used thesulfur oxide reduction becomes greater reaching about 80% when the lime is in twicestoichiometric ratio. The additional removal of sulfur with still more lime occurs more slowlyas the curve tends to asymptote and therefore ordinarily much greater excesses than twice

stoichiometric are not economically worthwhile. With quite high sulfur coal the theapproximate 80% reduction brings the fuel within environmental standards. Lime, while not avery expensive material still adds to the cost and in some cases with lower sulfur coals a 50%sulfur oxide removal brings the fuel within environmental standards and in such cases smallerexcesses of lime may be used. This is an economic question and there is no sharp upper limit.Theoretically calcium sulfate (gypsum) which is recovered by electrostatic precipitation orother means can be sold. However, the cost of producing the recovered gypsum may be morethan its sale price so, where unneeded for environmental purposes, smaller lime excesses can

present an economical advantage and are of course included.


13/28

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic showing of an experimental furnace burning the coal dispersion in abed;

FIG. 2 is a curve showing SO.sub.2 removal for various amounts of lime up to 50% excesses;

FIG. 3 is a diagrammatic flow sheet of a practical installation atomizing the coal dispersion toform a flame.


14/28

FIG. 4 is a semi-diagrammatic illustration of an ultrasonic probe.

DESCRIPTION OF THEPREFERRED EMBODIMENTS

FIGS. 1 and 2 deal with an experimental set up in which the coal dispersion is burned in a

bed. The coal dispersion is typically produced by dispersing 20 parts of coal in 10 parts ofwater adding 15 parts of oil, such as No. 2 heating oil, and subjecting the product to violent

ultrasonic agitation with an energy density of between 38.75 to 54.25 watts per cm.sup.2. Inorder to permit rapid dispersion the thickness of the liquids in contact with the vibrating

surface is of significance, for example, in an ultrasonic probe which will be described incombination with FIG. 4. The thickness of the liquid layer is not sharply critical, but should

be normally considerably less than the diameter of the vibrating surface. If the thickness ofliquid becomes much greater the output is reduced although if sufficient time is given asatisfactory dispersion can be produced in quite a thick liquid layer, however, this iseconomically undesirable. Obviously, of course, the thickness of the layer of the suspension

between the vibrating surface and container must be greater than the dimensions of the largestcoal particles. As has been stated above, the particular size range is from about 1.mu. to about100.mu.. Although it is not practical to get an exact measurement the dispersion appears to befairly uniform.

The present invention is not limited to any particular finely divided coal. Typical coals in the

specific embodiments to be described are an eastern bituminous coal having from 1 to 2% ofsulfur. Another typical coal is a western Kentucky coal having slightly more sulfur.

To produce a coal dispersion which will reduce sulfur oxide production on combustionpulverized lime in a water slurry is introduced at about the same time as the oil. The water inthis slurry must of course be taken into consideration for the water proportion. If the coal isvery low sulfur a lime excess of around 50% of stoichiometric can be used. For higher sulfurcoals, for which the present invention is particularly advantageous, the excess should be abouttwice stoichiometric.


15/28

Turning back to FIG. 1 the experimental furnace is shown at (1) and is preheated electricallyas is shown by the wires going to a surrounding electrical heating jacket. In the experimentalset up the furnace was a cylindrical furnace about 1.25 inches in diameter. The coal dispersionis introduced and forms a bed on a suitable burning grate (2). Air is introduced as is shownand the amount of air should be approximately that corresponding to most economicalcombustion, i.e. a slight excess of air. The gases from the burning bed pass into a sidearm

testube (3) which is filled with glass wool. This removes some solids and other impurities andthen passes into a water scrubber (4) which in the experimental set up contains water withabout 3% hydrogen peroxide. Then the gases pass on to a trap (5) and to a water trap (6) bothin the form of sidearm flasks, the latter containing glass wool. The gases are pulled through

by a partial vacuum as indicated on the drawing from any source, (not shown). Flow ismeasured by a rotameter (7).

Results of the tests are shown in the following table 1:

TABLE 1

____________________________________ ______________________________________

Removal of SO.sub.2 by Limestone in coal-oil-water suspension

__________________________________________________________________________Run No.

Type of Fuel 16N NaOHBurn (Grams)

Oil H.sub.2 OLimestone

Burnt(SO.sub.2 titrate)

SO.sub.2(Grams)

(Grams)(Grams)

Gramsml removal %

____________________________________________ ______________________________1 Bed 20 20 5 0 9.5 6.3 0

20 20 5 .48 10.0 4.4 3320 20 10 0 8 7 0

2 Bed 20 20 10 .48 7 4.5 263 Bed 20 20 10 0 10 9 0

20 20 10 1.5 10 4.9 444 Bed 20 20 10 0 6 4.8 020 20 10 1.5 6 2.4 50

5 Atomized20 15 10 0 6.9 2.5 0

Fuel 20 15 10 1.5 16 3.0 50Spray

__________________________________________________________________________


16/28

It will be seen that Table 1 includes a number of tests made with varying amounts of oil andwater and in each case included no finely divided lime or the number given in the table 1.This table also gives the amount of fuel burnt and sulfur oxides were measured by titratingwith a sodium hydroxide solution.

The first four runs were burned in a bed, the fifth run atomized the fuel from the end of an

ultrasonic probe. The sulfur oxide removal versus lime is shown as a graph up to 50% excessin FIG. 2. When the excess becomes greater than twice stoichiometric the curve flattens out orasymptotes at about 80% removal. In other words, in such a range the curve is actually an S.Curve.

FIG. 3 is a diagrammatic illustration of a practical flow sheet for a large plant. In this case thecombustion is by atomizing the fuel from an ultrasonic probe. Coal, as shown on the drawing,is pulverized in a ball mill and pulverizer (8) and reduced to a particle size of less than100.mu., with some of the particles as small as 1.mu.. The coal is then fed by a vibro-feeder(9) into a stream of water flowing at a controlled rate into a slurry tank (10). Slurrying iseffected by a conventional propeller, a vent to the air providing deaeration. The slurry then

passes through a controller and oil controlled by controller (11) is introduced and a little

further on a lime slurry passes through in the controller (11). The proportion of lime to sulfurin the coal is about twice stoichiometric.

The slurry is then premixed in a premixer (16). The premixed slurry is then introduced into asonic disperser (13) in this disperser an ultrasonic probe operating at between 20,000-22,000Hz of the type shown in FIG. 4 which will be described below and the end of the probe whichis operated from the front of the container (13) to produce a thickness of liquid substantiallyless than the cross sectional dimension of the end of the probe. Violent sonic agitation withcavitation resulted in the energy intensity being about 38.75 to 54.25 watts per cm2. A stabledispersion is produced which flows into a separator (14) provided with a weir (15) this weir

permits some supernatant oil to flow over into a compartment from which the recycling line(16) recycles it to the premixer (12).

The coal-water-oil-lime then flows into another ultrasonic probe housing (17) and is atomizedfrom the end of the ultrasonic probe into a combustion chamber (18). It is burned and the fluegases pass through a particulate separator in the form of an electrostatic precipitator (19) thisremoves finely divided calcium sulfate which can be recovered and sold. With coal having 2-3% sulfur the removal of sulfur dioxide is about 80% which brings the flue gases toenvironmental standards.

FIG. 4 is a semi-diagrammatic showing of a typical ultrasonic probe (20). Ultrasonicvibrations from 20,000-22,000 Hz result from electricity at the same frequency which isshown coming in through wires. The vibration is in a piezo-electric stack (21) to which is

coupled the broad end (22) of a steel velocity transformer which tapers exponentially to asmall end (23). It is this end which agitates the dispersion in the agitator (18) on FIG. 3 and asimilar probe produces atomization as indicated at (17) in FIG. 3.

Combustion of the atomized fuel produces a flame which is clear and results in completecombustion and which does not have the appearance of a flame from pulverized coalcombustion. The presence of water in the fuel dispersion is probably what assures theflamequality and which permits very complete combustion. The combustion is so complete


17/28

that there is very little if any loss in heating due to the presence of water which, of course, isflashed into steam as the dispersion burns.

US Patent # 4,048,963

( US Cl. 123/25R ~ September 20, 1977 )

Combustion Method Comprising Burning an Intimate Emulsion of Fuel and

Water

Eric C . Cottell

Abstract --- A combustion process in which a water-in-oil emulsion of liquid fuel, such asliquid hydrocarbons, containing from 10 to 50% water and preferably 10 to 30% water is

burned. The emulsion is produced, with little or no added emulsifying agent, by sonic

agitation, including a sonic generator and an acoustic transformer having a larger cross-section coupled to or in contact with the sonic generator than at its other end, at whichemulsification takes place, whereby the sonic energy density is increased. With the increasedsonic density an emulsion is produced which when burned produces a quality of burn suchthat the combustion is faster, more complete, and cleaner, with an increase in efficiency evenup to 30% of water. The increase in efficiency often equals that obtained by the burning of thesame weight of pure fuel in the conventional manner.

References Cited

U.S. Patent Documents2704535 - 2947886 - 2949900 - 3070313 - 3145931 - 3200873 - 3374953 - 3606868 -3658302

Parent Case Text

RELATED APPLICATIONS

This application is a continuation-in-part of my earlier application Ser. No. 489,710, filed July

18, 1974, which application in turn was a continuation-in-part of my application Ser. No.280,967, filed Aug. 16, 1972, and which was a division of my application Ser. No. 122,632,

filed Mar. 1, 1971, which is now U.S. Pat. No. 3,749,318, July 31, 1973. All of the earlierapplications above referred to except Ser. No. 122,632 are now abandoned.

Description

BACKGROUND OF THE INVENTION

The combustion of liquid fuel, such as liquid hydrocarbons, is a standard method of powerand/or heat generation. The combustion may be in a system where the heat is transferred toanother medium, such as water, with or without boiling the water, or the fuel may be burnedin various types of internal combustion engines, such as those operating on Otto, diesel, or

other cycle. The amount of oxygen, usually air, is at least about theoretically sufficient forcomplete combustion of the fuel elements.


18/28

Considerable problems have arisen. If there is a very large excess of oxygen, the efficiency ofthe combustion process is lowered because a considerable amount of air, including inertnitrogen, has to be heated up. In the case of an internal combustion engine also operating withexcessive excesses of oxygen can result in slow combustion, which can overheat and burn outexhaust valves. If the combustion is with amounts of oxygen and fuel more nearly in balance,for example with only a small excess of oxygen, problems arise with incomplete combustion.

This can result in excessive amounts of carbon monoxide and/or incompletely burned fuel,which may show up as unburned hydrocarbons, soot, and the like. Incomplete combustionlowers the combustion efficiency and can also contaminate the equipment. In the case ofinternal combustion engines, unburned hydrocarbons, carbon monoxide, and oxides ofnitrogen, generally symbolized by the formula NO.sub.x, are serious atmospheric pollutantsas they give rise to photochemical smog and the like. Contamination of nitrogen oxides froman internal combustion engine usually results when combustion temperature is high.

It has been proposed in the past to introduce streams of water into a burner or to inject waterinto an internal combustion engine as it operates. This has proven to reduce somewhat

incompletely burned fuel desposited in the form of carbon, and in the case of internalcombustion engines this can lower nitrogen oxide production and also in certain cases, such as

aircraft piston engines, permit operating for short times at higher power outputs with very richmixtures which would otherwise burn up the engine. Water injection, however, has seriousdrawbacks.

Problems have arisen in the control of relative amounts of water and fuel precisely, and evenif the control is maintained to a satisfactory degree, efficiency drops because the water has to

be vaporized.

It has also been proposed to produce an emulsion of hydrocarbon fuel and water by sonicvibration and then to burn this emulsion in a burner. This is described, for example, in theU.S. Pat. to Duthion, No. 3,658,302, Apr. 25, 1972. The Duthion patent utilizes a form ofsonic agitation produced by impinging a jet of the liquids against the edge of a blade free tovibrate. This form of sonic device is known in the art as a liquid whistle and was developed

by the inventor of the present application, whose earliest U.S. Pat. is No. 2,657,032, Oct.1953. While the emulsion produced is capable, in some cases, of being burned in a burner,

particularly when a considerable amount of surfactant is added, it does not burn completelyand produces an amount of heat which is usually less than that obtained by burning the fuelcontent because with the poor quality of emulsion the heat required to vaporize the waterreduces the efficiency.

The present invention deals with an improved water-in-oil emulsion with which much higherefficiency is produced.

SUMMARY OF THE INVENTION

The present invention burns a sonically emulsified, extremely fine water-in-oil emulsion,normally of hydrocarbonaceous fuel, in which the water droplets are of extremely fine particlesize. The emulsion is effected by sonic generator coupled to an acoustic transformer, with alarger cross-section coupled to or in contact with the sonic generator than at its other endwhere the emulsion of the present invention is produced. Because the sonic energy isdistributed over a much smaller area, the energy density is greatly increased. Since the sonicgenerator is operated at a fixed, predetermined frequency, the transformation in the


19/28

transformer causes the velocity of movement and also its path length at the small end to beincreased in order to comply with the law of conservation of energy. For this reason theacoustic transformers of the type described above are often referred to in the art as velocitytransformers and the two terms are synonymous. The small end of the acoustic transformeremulsifies fuel and water in a restricted space through which the two liquids flow. Energydensities of about an order of magnitude greater than those obtainable in the liquid whistle

type of sonic agitator are readily obtained and produce an emulsion which is not onlyburnable but which when burned produces combustion efficiency such that the yield of usefulheat, from say a conventional boiler, is almost the same as if pure oil had been burned.Therefore, improvements in efficiency of 10% to 30% are not uncommon. When used in aninternal combustion engine, flame temperature is decreased but the total amount of power

produced by the engine is as great as by burning a comparable amount of unemulsified fuel.The invention is not limited in its broadest aspect to a water content of from 10% to 30%water as emulsions having up to 50% water are still burnable though they do not produce asmuch heat as would be obtained by burning the same total quantity of unemulsified fuel. As iswell known, acoustically it makes no difference whether the acoustic or velocity transformerhas its large end in contact with the sonic generator or whether it is coupled to the sonicgenerator, for example through a resonant metal bar. In the claims the term "coupling" or

"coupled" is used generically wherever the sonic energy is transmitted, substantially withoutloss, from the sonic generator to the large end of the transformer and is not limited to actual

physical contact of the large end with the vibrating crystals or other elements of the sonicgenerator or through a coupling element.

The water content is not critical within its range, optimum results being obtainable with about30% of water in an ordinary burner and less when the emulsion is used in an internalcombustion engine; for example, optimum results are obtainable with about 18% to 20%water. In every case very clean combustion takes place, minimizing contamination and

pollution, and in an internal combustion engine emission controls are readily met.

The surprising result of obtaining as much heat from an emulsion as with unemulsified fuelhas been repeatedly tested. While I do not want to limit the present invention to any particulartheory of why this suprising result takes place, it seems probable that the combustion of theemulsion in which the microscopic water globules explode into steam is more complete. Thesurfaces of a furnace or boiler encountering the flame may be below the condensation point ofwater or above, the latter being more common unless hot water at fairly low temperature is to

be produced. In the case of an internal combustion engine temperature, the inner surfaces ofthe cylinder and the top of the piston are always above the condensation point of water whenthe engine is operating. The tests made and described in a later portion of the specificationwere with furnaces and engines where the surfaces were at a temperature higher than thecondensation temperature of water, and therefore the improved results do not depend on thecondensation of water vapor on cooler surfaces.

I also do not want to limit the invention to any particular theory of why the optimum watercontents are somewhat lower for an internal combustion engine than for a burner in anordinary heating furnace. A possible explanation might be that the heating oils have anaverage boiling point above that of water and, therefore, in the flame are completely explodedinto steam without significant vaporization of the hydrocarbon fuel. In the case of gasolineused in the internal combustion engine tests, which will be described below, the average

boiling point of gasoline is lower than that of water, and therefore it is possible that there may

be some vaporization of gasoline during combustion before all of the water has been flashed


20/28

into steam. There has been no rigorous proof of the above explanations but they are plausiblepossibilities and may well be part or all of the explanations of the surprising results obtainedby the present invention.

In the internal combustion engine modification of the present invention, while the totalamount of power may be as great or, under certain circumstances, even greater, the peak

flame temperature is usually lower, and it seems probable that the reduced emission ofnitrogen oxide results primarily from this factor. However, this is not known, and the watervapor present in larger amounts as compared to carbon dioxide may also play a part.Therefore, it is not intended to limit the invention to any particular theory, and the abovestatements are made because I think the factors mentioned are at least some, and conceivablythe only, factors involved.

The invention is not limited to the time in the whole operation when the very fine water-in-oilemulsion is actually produced. This may be at the point where atomization takes place just

prior or at the point of ignition. This, however, is not necessary, and the emulsion may bepreformed and conveyed to the burner nozzle in a preformed state. The emulsions obtained bysonic agitation including the acoustic transformer are quite stable and so they can be produced

at a point remote from the actual burner itself, and such a modification is, of course, included.It is also possible to have the emulsion formed by flowing water and oil over the emulsifying

point, preferably the end of a sonic probe, so that the emulsion is formed at the same place, orpractically at the same place, as atomization into the flame takes place. In the case of the useof sonic atomization, particularly for internal combustion engine use, which is described andclaimed in my co-pending application, U.S. Pat. No. 3,756,575, issued Sept. 4, 1973, referredto above, it is usually preferable to have the streams of water and fuel unite just prior to the

point of atomization.

It is an important advantage of the present invention that it is not necessary to use anyemulsifying agent, particularly when sonic emulsification is used. This eliminates the addedstep and, therefore, cost of the emulsion is reduced, although in a broader aspect the presentinvention does not exclude an emulsion which has been made in the presence of a smallamount of an emulsifying agent, such as a small amount, usually a fraction of a percent, of adialkyl sulfosuccinate or other well known emulsifying agent capable of facilitating theformation of water-in-oil emulsions. The invention in this aspect, which is normally not

preferred, may use any known emulsifying agent.

Ordinarily more problems are presented with the burning of heavy residual fuel oil, and thisfrequently requires steam heating. In the case of the present invention, however, the heavy oilemulsifies more readily than light oil, and when emulsified with a considerable amount ofwater, the viscosity is low enough so that it may be burned without preheating, or with less

preheating, or at a lower temperature where cold water is added. This is an additional

advantage for use with heavier oils. Why the heavy oil emulsifies more readily and to a lowerviscosity has not been fully determined. It is possible that the heavy fuel oil containscontaminants which aid in the emulsification which are not present in the purer lighter fueloils. It is not intended, however, to limit the present invention to any theory of action.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows, in diagrammatic form, a sonic emulsifier and a burner;


21/28

FIG. 2 is a detail on a somewhat enlarged scale, partly in section, of the emulsifier;

FIG. 3 is a semi-diagrammatic illustration of a combined sonic atomizer and emulsifier,especially useful with internal combustion engines, and

FIG. 4 is a cross-section through a modified form of sonic probe.


22/28

DESCRIPTION OF THEPREFERRED EMBODIMENTS

In FIG. 1 a sonic generator 1 is shown powering a sonic probe in the form of an acoustictransformer 2, the end 9 of which extends into a chamber 3 through a flexible seal 4 locatedsubstantially at a nodal point of the sonic probe. A stream of fuel, such as house heating fuel

oil, is introduced through a conduit 5 and a stream of water joins it through a conduit 7 with afail safe valve opened by fuel pressure. These two streams strike the vibrating end 9 of thesonic probe, as can best be seen in FIG. 2 where a portion of the chamber 3 is shown insection. The violent sonic agitation emulsifies the two streams, which then leave axiallythrough an outlet conduit 6 in a plate 10 which is located closely adjacent to the vibrating end9 of the sonic probe. From the outlet conduit 6 the emulsion passes into a conventional burner8 in a combustion chamber, (not shown). Air is introduced at 26 and a flame results. Whilethe proportions of fuel and water can vary over a wide range, for example from about 10% toabout 50% water, a very suitable mixture is about 70% fuel and 30% water.

The sonic probe is of conventional design with a stack of piezoelectric plates, (not separatelyshown), which are energized through the cable 12 by a suitable high frequency oscillator, (not

shown), which may operate, for example, at a frequency of approximately 20,000 HZ. Theplate 9 at the end of the sonic probe 2 may be a flat plate or it may also be provided with asuitable baffle, for example a spiral baffle, to extend the period of residence in the violentsonic agitation field. The sonic generator illustrated diagrammatically is of a commoncommercial type sold by the Branson Instruments under their trade name "Sonifier." The

particular design of the sonic emulsifier has nothing to do with the present invention and theillustration shows merely a typical one. The combination of the sonic generator and acoustictransformer is essential to produce the increased energy density on which the results of the

present invention depend. However, the invention may use any other design having a sonicgenerator and an acoustic transformer producing comparable energy densities.

FIG. 4 illustrates a more recently developed Sonifier by Branson Instruments which has

certain practical advantages, at least for larger burners. It is shown in cross-section. 1 is thegenerator, which is a stack of conventional piezoelectric crystals. These crystals are not of as

large cross-section as the corresponding generator in FIGS. 1 and 2 because they are coupledto an acoustic transformer, which, as it performs the same function as the transformer in

FIGS. 1 and 2, bears the same reference numeral 2. The coupling is through a half-waveresonant rod 17, which couples to the large end of the acoustic or velocity transformer 2. Thelarge end is shown at 18, and the transformer can be clamped by the flange 25 whereadditional rigidity is desirable since the modified Sonifier is considerably longer in lengththan that shown in FIGS. 1 and 2. The small end 32 of the transformer is bolted to and


23/28

therefore coupled to a rod 21 at the end of which there is the same kind of plate 19 as isshown in FIGS. 1 and 2. The rod is provided with lands 24 and elastomeric rings 23. This isthe portion which is at an approximate quarter wavelength and which seals the containerwhere the emulsion is produced. This container and associated elements are the same as inFIGS. 1 and 2. Therefore, they are not repeated in FIG. 4. The modified Sonifier has theadvantage that it is not limited to a single size of acoustic transformer and can be used with

transformers of various cross-sectional ratios. Also, it is provided with a clamping flange 25,as has been described, which permits much more rigid construction and makes it suitable for alonger probe. The operation is exactly the same. The vibrations produced by the vibratingcrystals are coupled to the acoustic transformer 2 and the energy density is increased in thesame way as by the transformer in FIGS. 1 and 2.

The equipment of FIGS. 1 to 4 produce the same increased energy density at the small end ofthe probe. It should be noted that this is energy density, i.e. violence of agitation, which iseffected by longer paths, hence the alternative name of velocity transformer. It is energydensity which is required in the present invention and not total power input. As has been

stated earlier, the energy density is about an order of magnitude greater than can be producedin a liquid whistle, and in the probes of FIGS. 1 to 4, for illustration, this energy density is

approximately 37 watts/cm.sup.2.

As illustrated and described above, stable fuel and water emulsions of the water-in-oil typeare produced, and when these emulsions are burned combustion results in a boiler weremeasured in relative times to bring the water in the boiler jacket from a particular temperatureto a temperature just below its boiling point. The test accurately measures the relative heatingefficiencies and is shown in the following table, which illustrates the results of eight tests,tests 1 to 5 being with straight No. 2 domestic heating oil and tests 6, 7 and 8 with a mixtureof oil and water.

______________________________________TEMPER- TEMPER-ATURE (1) ATURE (2) TIME MATERIAL

______________________________________1. 150 degrees 192 degrees Oil2. 150 " 194 " 4-13" Oil3. 150 " 194 " 4-14 Oil4. 146 " 192 " 4-6 Oil5. 144 " 194 " 3-40 Oil6. 146 " 194 " 3-30 600 Oil

325 Water7. 144 " 192 " 4-20 850 Oil

200 Water

8. 144 " 196 " 4-16 800 Oil250 Water______________________________________

Boiler surfaces were carefully examined in the tests and were clean. A flame was producedwhich was whiter; there was no visible smoke from the chimney, and stack gas analysisshowed a more complete and perfect combustion.


24/28

Tests were made comparing water-in-oil emulsions produced in a standard commerciallyavailable liquid whistle which is similar to the design described in the first Cottell U.S. Pat.

No. 2,657,021, referred to above, with emulsions produced by emulsifiers used in the presentinvention and described in FIGS. 1 to 3. Liquid pressure in the liquid whistle was 200 psi andthe energy density level in the sonic emulsifiers was approximately 37 watts/cm.sup.2 orabout an order of magnitude greater than in the liquid whistle. The tests with various amounts

of water and No. 2 heating oil were compared in two respects, one, stability, i.e. time for onsetof emulsion inversion, and, two, flame characteristics.

_____________________________________________________ _____________________Water in Oil

Liquid WhistleUltrasonic Fuel Reactor

Remarks on Remarks onEmulsion

Time for OnsetTime for Onset of

Combustion ofLiquidCombustion of

Water % of InversionInversion Whistle Emulsion

Ultrasonic Fuel

__________________________________________________________________________5% 5" 180" Intermittent flame

Bright, consistentFlame out in app. 8

flame, no smokesec. Smoke, possiblydue to combustionfailure

10% 3" 150" Intermittent flameBright, consistent

Flame out in app. 3flame, no smoke

sec. Smoke, possiblydue to combustionfailure


Flame out in app. 2flame, no smokesec. Smoke, possiblydue to combustionfailure


Flame out in app. 3flame, no smoke


25/28

sec. Smoke, possiblydue to combustionfailure

__________________________________________________________________________

It will be seen that at all water contents much more stable emulsions were produced in theultrasonic fuel reactor of the present invention and the flame was excellent whereas emulsionsfrom the liquid whistle produced intermittent flame accompanied by smoke, and in theoperation flame out actually occurred.

FIG. 3 illustrates a modification particularly useful for internal combustion engines. Theultrasonic probe carries the same reference numerals as in FIGS. 1 and 2, but the shape of theend of the probe is a little different, being expanded out into a plate 10. Gasoline wasintroduced through the conduit 14 into an annular space between the probe and a housing 15,and water was introduced through conduit 13. The two liquids flow down until they come tothe edge of the expanded plate 10, where they proceed to flow along the top of the plate andare atomized and emulsified at the same time. Air is introduced adjacent the atomized

emulsion through an air conduit 16 and the resulting mixture is fed into the manifold of aninternal combustion engine, (not shown).

The plate 10 projects beyond the housing, the clearance between housing and ultrasonic probebeing exaggerated and the violent sonic agitation of the plate throws a finely divided emulsionup from the upper surfaces of its projection. As FIG. 3 is designed to connect with a manifoldof an internal combustion engine, there will usually be a certain amount of vacuum, and thiscauses the emulsion to be pulled around the edge of the plate, as is shown by the arrows.Thorough mixing of the air takes place, but it is not necessary that the emulsion be thrown bysonic vibration into the manifold, whereas in FIG. 4 with the horizontal burner this isnecessary so that the fine emulsion atomized in the blast of air moves horizontally to form the

burner flame. It is for this reason that the actual contact of the plate with the film of fuel andwater flowing over it is on its forward face so that it will be thrown in the direction to formthe burner flame, for of course in an ordinary burner there is not the vacuum which exists inan internal combustion engine manifold.

The internal combustion engine fed with a gasoline and water emulsion atomized into the airran with the same power as on straight gasoline, and pollutants were reduced, unburnedhydrocarbons practically zero, carbon monoxide greatly reduced, and nitrogen oxides stillmore reduced. The figures illustrate the pollutant concentrations, the engine running at about5,000 rpm under load. It will be noted that the pollutant concentrations are far below presentemission standards and even meet more rigid standards proposed for later years. Carbonmonoxide 0.94% unburned hydrocarbons 0.0, nitrogen oxides 11.35 ppm.

Cottell Patents @ Espacenet (European Patent Office)

Production of FuelPatent Number: US4377391Publication date: 1983-03-22Inventor(s): COTTELL ERIC C


26/28

IPC Classification: C10L1/32; C10L9/00EC Classification: C10L1/32B

Abstract ~The production of fuel comprising an emulsion of coal particles, oil and water or adispersion of coal and oil in which pyrites, ash and other impurities are removed from the coal

particles and the particles reduced in size by forming a slurry of contaminated coal particles

and water and exposing that slurry to violent sonic agitation to cause the impurities to bedetached from the coal particles and the particles to be reduced in size. The coal andimpurities are thereafter separated and the coal subsequently incorporated into a fuel. The

process may also be used to separate other minerals which are bonded mechanically asdistinct from chemically, to each other.

Process for Beneficiating and Stabilizing Coal/Oil/Water FuelsPatent Number: US4326855Publication date: 1982-04-27Inventor(s): COTTELL ERIC C

EC Classification: B01J19/10, B03B9/00B, C10L1/32BEquivalents: BR8007307, DK152808B, DK152808C, DK469080, FI74727B, FI74727C,FI803330, GR71927, ZA8006719

Abstract ~A coal slurry containing 10-60% solids by weight is optionally first coarselyground to about 20-80 mesh. Contaminant matter released thereby, may be separated byconventional means such as froth flotation which would eliminate a large proportion of theash which is energy consuming as well as abrasive in nature. The "clean slurry" would nowhave water added back and would be further ground to about 100-300 mesh particle size andwould then be cavitated by sonic energy making the particle size even smaller and freeing anyremaining contaminants including iron pyrites and ash. To this, a mixture of oil is added andthe coal, oil mixture is then sonified during which process spherical agglomeration of the coaland oil occurs. The agglomerate and water mixture is screened to separate out most of thewater leaving behind about 10-40% water in the coal, during which process the contaminantsare also discharged with the water. The spherical agglomerates are mixed with a balance of oilto about 0.6 times the weight of the coal to produce a stable thixatropic fuel with excellent

pipe travel characteristics due to a migration of a thin film of water to the boundry layerbetween the bore of the pipe and the fuel. The process including the sonification steps is alsouseful generally in the separation of solids by agglomeration.

Fuel Supply System

Patent Number: US4273078Publication date: 1981-06-16Inventor(s): COTTELL ERIC CIPC Classification: F02M37/00EC Classification: F02M25/02B

Abstract ~A fuel supply system comprises a supply tank with a main fuel conduit leading toa combustion zone, such as an internal combustion engine, and a secondary fuel conduit withflow restriction means is provided leading from the lowermost region of the tank to rejoin the


27/28

main fuel conduit prior to the combustion zone so that any water accumulating in the tank ismixed with fuel to be burned at the combustion zone.

Production of Fuels

Patent Number: US4218221Publication date: 1980-08-19Inventor(s): COTTELL ERIC CIPC Classification: C10L1/32; B01F11/00EC Classification: C10L1/32D

Abstract ~Apparatus and method for producing a fuel comprised of oil and water in which amixture of oil and water is constituted as an emulsion by exposure to agitation effective tocause cavitation within the mixture.

DE 1053475 ~ No English title available.GB 836439 ~ Improvements relating to the automatic regulation of the rate of flow of a fluidthrough a pipe or the likeGB 738773 ~ Improvements relating to the automatic regulation of the rate of flow of a fluidthrough a pipe or the likeGB 1013757 ~ Rotating liquid whistleDE 2967000D ~ No English title available.ES 8200717 ~ No English tit le available.

NO 823620 ~ No English title available.NO 803369 ~ No English title available.NO 793491 ~ No English title available.IT 1209772 ~ No English title available.IT 1124414 ~ Fuel supply for turbine or fuel injected IC engineFI 803330 ~ No English title available.US 5009197 ~ Method of removing oil from birds and animalsUS 4412842 ~ Coal beneficiation processUS 4412512 ~ Fuel supply systemUS 4400177 ~ Fuels and methods for their productionUS 4377391 ~ Production of fuelUS 4326855 ~ Process for beneficiating and stabilizing coal/oil/water fuelsUS 4273078 ~ Fuel supply systemUS 4218221 ~ Production of fuelsUS 4048963 ~ Combustion method comprising burning an intimate emulsion of fuel and

waterUS 3941552 ~ Burning water-in-oil emulsion containing pulverized coalUS 3696973 ~ Hand-Held Air Compressor and Liquid Spray DeviceFR 2196011 ~ No English title available.FR 2190247 ~ No English title available.FR 2113655 ~ No English title available.WO 8203085 ~ Processes for Clewaning Minerals...EP 0020711 ~ Fuel and Water Emulsification System.EP 0016184 ~ Fuels and Methods for their Production


28/28

DE 2239408 ~ No English title available.DE 2230071 ~ No English title available.DE 1447328 ~ No English title available.CH 657067 ~ Process for separating suspended solids and agglomerated other solids insuspending and bonding liquids respectivelyCH 572578 ~ No English title available.

CH 562991 ~ No English title available.CH 536132 ~ No English title available.CA 1104345 ~ Residual Oil in Emulsion of Water with Distillate OilCA 973795 ~ Combustion Method Comprising Burning an Intimate Emulsion of Fuel andWaterCA 967947 ~ Apparatus for Carrying Out Ultrasonic Agitation ofLiquid DispersionsCA 963375 ~ Combustion Method Comprising Burning an Intimate Emulsion of Fuel andWaterCA 962905 ~ Apparatus and Method for Producing a Fuel-Air Mixture by Sonic EnergyBR 8108998 ~ No English title available.BE 886087 ~ No English title available.BE 787603 ~ No English title available.

BE 785280 ~ No English title available.BE 774982 ~ No English title available.

NL 8006086 ~ No English title available.

Your Support Maintains this Service -- and Your Survival ...

The

Civilization Kit... It's Your Best Bet & Investment in Sustainable Humanity on Earth ...

Everything @ rexresearch.com, plus the Bonus Files CD !

> from :

Rex Research, POB 19250, Jean, NV 89019 USA

ORDER PAGE