US 3383049 A
Description (OCR text may contain errors)
' May 14, 1968 R E. GUERIN 3,383,049
MEANS OF COMBAT ING ATMOSPHERIC POLLUTION AND A CORRESPONDING BURNER Filed Oct. 11, 1966 FIG. 7
United States Patent 4,500 6 Claims. (Cl. 239-400) ABSTRACT OF THE DISCLOSURE A fuel burner having means to controllably combine a fluid fuel, water in a liquid form and air then atomize the combination to form an atomized combustible mixture.
In the present state of the art it is known to prepare and use emulsions of fuel and air for some burners with air atomization.
Various methods are known of adding water when burning fuel oils; these consist either of injecting atomized water directly into the hearth, of previously preparing the emulsion or of atomizing the fuel using the water vapor as an auxiliary fluid.
In order to use water vapor as an auxiliary fluid for atomization it is necessary to have about 1 kg. of vapor to atomize each kg. of fuel, which represents a fairly 'large loss of energy. Example: to operate some furnaces consuming 500 kg. of fuel per hour it is necessary to provide a boiler producing 500 kg. of steam per hour, which itself will consume about 50 kg. of fuel per hour or of the necessary consumption. It is calculated that 1,000 kcal. have to be provided in order to produce 1 kg. of steam, which will introduce only 600 kcal. into the hearth after atomization with good combustion.
The purpose of the present invention is to eliminate this disadvantage; it also provides considerable advantages which will be explained hereinafter.
The method of the invention uses water in the liquid state in variable proportions according to requirements, in order to produce in situ (in the nose of the burner) a multiple emulsion made up of three or more fluids, namely hydrocarbon, Water (pure or with additives) and air (or another gas, possibly with additives).
To go into greater detail, the emulsion according to the invention may be made up of:
(1) a pure hydrocarbon or a liquid mixture;
(2) pure water, or water with soluble substances added (salts of minerals or metals) to react with the H 80 formed by combustion of the sulphur in the fuel in order to neutralize the acidity of the fumes so as to decrease atmospheric pollution; the soluble salts may also be selected to change the physical properties of the flame (temperature, volume, radiation factors or heat exchange); or water containing in solution a diiferent hydrocarbon, such as alcohol, or a different pure liquid acting as a combustion supporter;
(3) air or a combustion supporting or carburetant gas, whether or not it carries solid particles which are used either to modify the flame or to combat the harmful effect of the H 80 in the residual gases, for example metal oxide powders.
The possible applications of the method of the invention are very extensive; they can make it possible to produce flames of quite variable characteristics, giving much sought after properties which cannot be obtained by methods hitherto known in the combustion of liquid hydrocarbons.
As a non restrictive example of its application, the invention will be described with reference to the accompanying drawings, in which:
FIG. 1 is an axial section through the burner according to the invention;
FIG. 2 is an end elevation of the burner with the nose removed and FIG. 3 shows a partial detail in a section taken along the line IIIIII in FIG. 2.
In the burner comprising a body 1 a shaft 3 is displaced within bore 2 of the body; the shaft has both rotary and translatory movement imparted to it by the controlled rotation of a threaded portion 4 moving within a tapping 5 in the body 1. Rotation may be controlled manually (wheel 6) or automatically; in the latter case the wheel 6 being replaced by a lever controlled by a servo-motor, the servo-motor acting according to whether the working of the installation is controlled automatically or semi automatically. A sealed relationship between the shaft 3 and the body 1 is ensured by conventional means; for example, a threaded stopper 7 is screwed into the body 1 and exerts pressure on a packing 8 which is gripped between the stopper 7, the body 1 and a seat 9. The purpose of this. arrangement is to stop any liquid or gas from escaping between the shaft 3, which is movable, and the body 1 which is stationary.
The shaft 3 has an adjusting bushing 11 provided to seal the fuel (or hydrocarbon) inlet when the burner is stopped and to create a drop in pressure or a controllable conduit together with the fuel inlet passage 12, according to the application. The fuel (or fluid) passes into the gap 13' between the body 1 and the shaft 3, which is freed for the purpose, and flows through distributing slots 14 into the emulsion chamber 15 provided between the body 1 and the nose 16 of the burner; the distributing slots 14 are initially longitudinal (FIG. 1) and then radial (FIG. 2).
The air or atomizing gas arrives through a connection fixed onto the tapped hole 20 and passes through the two holes 21 into a distributing chamber 22 at a constant pressure equal to that of the other fluids. It is introduced into the emulsifying chamber 15 by passing through a plurality of tangential slots 23 which impart to it a rotary movement perpendicular to the fuel distributing slots 14. The slots 23 are hollowed out of the body 1 and the gas is channelled by virtue of the fact that the nose 16 bears on the flat end face of the body 1.
Discharging into each slot 23 is a groove 25 for the entry of water or various fluids, the groove being machined into the outer cylindrical portion of the body 1; the dimensions of all the fluid-channe=lling orifices are determined according to the required output. The grooves 25 enable an auxiliary fluid to be used and to be atomized by the gas on the front surface of the grooves 23; the grooves 25 are fed by an internal distributor 30 supplied through the orifice 31. The distributor 30 is fixed to the body 1; it is provided with screw threading 32 and receives the nose 16, which is screwed onto it.
In the center of its front surf-ace the nose 16 contains a port 34 which houses the needle 35 of the shaft 3. Rotation of the shaft determines the displacement of the needle towards the front or the rear of the burner body 1; since the nose of the burner is stationary, the area over which the emulsified mixture passes varies according to the output required; the three or more fluid-s making up the mixture are subject to a single action and a single control, and the needle 35 can totally seal the port 34 and stop the mixture from flowing out.
in the emulsifying chamber 15 the liquid and gaseous components are treated together and subjected to a vibrat-ory action, possibly ultrasonic; ejection takes place in the free area between the needle 35 and the nose 16 with a rotary movement of the droplets; the droplets together form a projection cone made up of intimately bonded carburetant and comburant, with or without other substances.
It will be noted that in accordance with the invention, in a burner where air or auxiliary gaseous fluid is used for atomization, a certain quantity of water (for example) is added and is intimately emulsified in a mixing chamber with a gaseous fluid and a liquid hydrocarbon. The percentages of the constituents of the mixture and their nature will vary according to the nature of the flame required and the purpose of the operation.
The invention has been found to provide the following advantageszl With the assembly according to the invention it is possible to obtain flames about 30 times greater in volume than those obtained by other known means, and at the same time to neutralize the harmful action of the H 50 and reduce the percentage of S polluting the atmosphere. The temperature obtained in the reaction medium is very uniform and may be varied according to the mixture.
The method of the invention makes it possible to gasify the carbon in the fuel or hydrocarbons and also to obtain combustible gaseous hydrides which can be recovered for use remote from the place of production, e.g. in gas generators.
The resultant combustion leaves no deposit of unburnt carbon and thus no soot; it makes it possible to introduce into the flame, with very uniform distribution, substances which will fix the H 80 formed by combustion of the sulphur in the fuels in order to combat pollution.
The active oxygen produced by dissociation of water oxidizes the sulphur more quickly and produces S0 almost exclusively instead of letting a quantity of S0 escape into the atmosphere; only traces of S0 are present, in the case of bad adjustment or when the atmosphere is deliberately made very oxidizing (for example in order to fire bricks).
This method of burning the fuel allows for complete combustion of the liquid hydrocarbons with very low percent surpluses; in some cases combustion may even be made and kept completely neutral, that is to say, for example:
Percent CO 15.8 02 .2 H .2 CH O CO 0 In this case the theoretical temperature of themixture is obtained at the same time, which proves that all the combustible substances have released their energy and that all the water is dissociated: here the yield from combustion may be very close to 100%. Corrosion is avoided in addition.
In industry, because of the properties of the flame, the process makes it possible to use fuel oil in cases where this was hitherto impossible, thereby producing a great saving. Example: certain earth-baking furnaces where wood or a natural combustible gas or a distillation gas still has to be used.
Below is the theoretical explanation that applicant thinks can be given of the invention and its advantages.
In order to gasify carbon by putting water, in vapor form or finely atomized but liquid, in the presence of the constituents of a fuel or other liquid hydrocarbon during flame-producing combustion the Water must be converted into high-temperature vapor, thus absorbing energy: this reaction abruptly cools the flame locally, and a large quantity of carbon ceases to be oxidized and forms unblurnt solids; moreover only a small percentage of water is dissociated (about 2%) during an endothermic reaction, to free active hydrogen and active oxygen; these two gases combine with part of the active carbon resulting from the cracking of the heavy elements in the fuel to produce a combustible gas, but the total energy absorbed as a result of the conversion of the water does not allow suflicient water to be introduced to gasify all the carbon that has been brought to about 1500 C.: if too much water or vapor is introduced the flame will be extinguished (amount less than 10% of liquid water).
The method of the invention permits the complete gasification of a mixture in combustion containing one third by weight of fuel and two thirds of liquid water, as a result of uniform changes throughout the flame; physical and chemical conditions of the reaction medium completely change the phenomena of chemisorption and absorption on which the oxidation of the carbon depends.
In ordinary combustion the very fine fuel droplet is subjected in the first phase to a rise in temperature which vaporizes the light elements, makes them combust and heats the heavy elements, bringing them to bet-ween 1500 and 2400 C. according to the surplus of combustion air and produces cracking to re-libera-te light elements. The process then starts again, but since the carbon is moving at fairly high speed within the flame it moves away from the hottest point and, as cracking temperature is no longer reached, this carbon is oxidized less quickly and is then not oxidized at all. It becomes red hot and radiant, liberating the heat energy which it transports, then becomes black to form the solid residues invisible to the naked eye, escapes in the residual gases and under certain physical conditions partly agglomerates and deposits in the form of soot.
In the method of the invention the hydrocarbon is, as in the last case, chemically atomized by air into fine droplets as in known methods, but it has been previously emulsified with water and air or gas. Each droplet contains the combustible hydrocarbon surrounding a gas bubble, the whole being surrounded with water; the emulsion may be oil in water or water in oil, according to the percentage of water in the mixture. Each droplet represents a reaction medium containing a carburetant, oil, a supporter of combustion and air, uniformly distributed in the presence of water. On introduction to the hearth the rise in temperature causes the gas to dilate and the thickness of the layer of oil to decrease, thereby enlarging the area of contact between the carburetant and the supporter of combustion and accelerating the combustion of the volatile elements. The rise in temperature simultaneously causes the heavy elements in each droplet to crack at about 1600, liberating active carbon, and the dissociation of water produces active oxygen 0 and active nascent hydrogen also distributed throughout the reaction medium, which contains about twice as much hydrogen by this method as by other present day processes. The phenomena of chemisorption and adsorption are accelerated and the chain of free radicals formed is different: carbon elements combine in larger quantities with hydrogen to form combustible gases which are oxidized to release energy. Since this process takes place throughout the very large flame, a gas flame, the total radiation factor is very high, in fact near the maximum, and neutral combustion can be obtained without difficulty in an appropriate medium. The result is an increase in useful energy and the possibility of using liquid fuels in certain above-mentioned cases where this was hitherto thought impossible, together with a reduction in atmospheric pollution.
What is claimed is:
1. A burner comprising a body, a distributor secured to the body, a nose adjustably mounted on the distributor and a shaft movably mounted in the body for adjustment therein, said body being provided with a fuel inlet passage, means on the shaft movable therewith and facing said inlet passage for controlling flow of fuel through said inlet passage in accordance with the position of the shaft in the body, said shaft having grooves for passage of fuel therethrough after passage by said means, said body, nose and shaft defining an emulsifying chamber into which said grooves open, the body having a liquid inlet orifice, said distributor having a channel in communication with said liquid inlet orifice and slots leading from said channel to said chamber, said body having an air inlet orifice and a passageway for air from said inlet to said slots to produce an atomized mixture of air and liquid which is supplied to said chamber and is emulsified with the fuel supplied thereto, said shaft including a terminal adjusting needle, said nose being provided with an orifice receiving said terminal adjusting needle for regulating the flow of the emulsified fuel, air and liquid in accordance with the position of the shaft in the nose.
2. A burner according to claim 1 wherein the shaft is threadably mounted for simultaneous rotational and translational movement within the body.
3. A burner according to claim 1 wherein the terminal adjusting needle is conical in shape and the flow is regulated by moving the shaft forward and backward to vary the space between the orifice and the conical needle.
4. A burner according to claim 1 wherein said grooves in the shaft are radially disposed therein and extend longitudinally along the shaft.
5. A burner according to claim 4 wherein said slots extend tangentially from said chamber in a plane perpendicular to said grooves.
6. A burner according to claim 1 wherein said means on the shaft for controlling flow of fuel through said passage comprises a bushing on the shaft.
References Cited UNITED STATES PATENTS 903,736 10/1908 Lee 239400 1,934,837 11/1933 Zulver 239400 2,539,314 1/1951 Murphy 239400 EVERETT W. KIRBY, Primary Examiner.
FREDERICK L. MATTESON, JR., Examiner.
H. B. RAMEY, Assistant Examiner.