US 3828700 A
A process and apparatus for use in treating industrial residues such as chemical waste which are in a liquid form but which are substantially uncombustible. The invention provides for the combination of the residues with at least 30 percent by weight combustible substances, preferably substances which are also waste materials, and the burning of the combination at the base of a chimney. The chimney is designed for the introduction of air into the burning zone, and a mechanism for producing a spray of the residue and substances introduced is utilized.
Description (OCR text may contain errors)
1451 Aug. 13, 1974 llited States Patent 1191 Ragot 12/1967 Brophy 110/7 3/1969 Wiesenthal 1/1970 Garver et al.......
718,102 2/1973 Hemsath et al.... 110/7 734,035 5/1973 Whitfield...............................
[ PROCESS FOR THE SMOKELESS BURNING OF RESIDUES, AND APPARATUS THEREFOR  Inventor: Raymond Ragot, Melle, France  Assignee: Speichim, Paris, France Primary Examiner-Kenneth W. Sprague Attorney, Agent, or FirmMcDougall, Hersh & Scott  Filed: Apr. 4, 1973  App1.No.: 347,852
ABSTRACT A process and apparatus for use in treating industrial  Foreign Application Priority Data Apr, 6, 1972 France 72.12702  Field of Search 431/5; 1 10/7 R, 7 S, 8 R, materials, and the burning of the combination at the 110/8 C base of a chimney. The chimney is designed for the introduction of air into the burning zone, and a mech-  References Cited anism for producing a spray of the residue and sub- UMTED STATES PATENTS stances introduced is utilized.
9/1965 Voorheis et al. 431/5 X 8 Claims, 10 Drawing Figures PROCESS FOR THE SMOKELESS BURNING OF RESIDUES, AND APPARATUS THEREFOR The present invention relates to a process for destroying or eliminating through burning or vaporization, residues, particularly industrial residues. The industrial residues referred to comprise more or less viscous liquids which may contain solid particles and which comprise, or have added thereto at least 30 percent by weight of combustible substances, as hereinafter defined. The invention also relates to various apparatus for realizing the described process.
It is known that in most industries it is often difficult to get rid of certain residues. Some of them can be burned, more or less easily. On the contrary, others can be burned only with difficulty or cannot be burned at all. The burning of many of such residues in open air, when possible, evolves considerable smoke which highly pollutes the atmosphere, and burning in conven tional incineration apparatus, such as conventional burning chambers and similar devices, gives rise to various inconveniences such as corrosion and clogging.
It is a general object of this invention to provide an improved system for the destruction or elimination of industrial residues.
It is a more specific object of this invention to provide a system of the type described wherein at least a substantial portion of the residues are noncombustible, the system nevertheless providing for the elimination of the residues and doing so in a manner such that significant pollution problems do not result.
These and other objects of this invention will appear hereinafter and for purposes of illustration, but not of limitation, specific embodiments of the invention are shown-in the accompanying drawings in which:
FIG. 1 comprises a schematic illustration of a chimney construction characterized by the features of this invention;
FIG. 2 is a schematic illustration of an alternative form of chimney construction and associated mechanisms operating in accordance with the concepts of this invention;
FIG. 3 is a schematic illustration of a further modification of the invention;
FIG. 4 is an enlarged cross-sectional view particularly illustrating a burning apparatus for use in the practice of the invention;
FIG. 5 is a cross-sectional view of an atomizer construction suitable for use in the practice of the invention;
FIG. 6 is a schematic illustration of a burner-injector combination characterized by the features of this invention;
FIG. 7 is a perspective viewof a turbulence ring structure utilized in the practice of the invention;
FIG. 7a is a side elevation of the structure of FIG. 7;
FIG. 8 is a perspective view of an additional turbulenee ring structure utilized in the practice of the invention; and,
FIG. 8a is a side elevation of the structure shown in FIG. 8.
In the following description, where reference is mad to spraying, it will be understood that this term includes the use of various mechanisms for injecting liquid material in a separated form including atomizing and pulverizing means, and wherein the liquid is in the form of a fine stream, a mist, or other forms achievable with mechanisms of the type described. It will also be understood that with respect to the material to be treated, both the process and the apparatus ofthe invention can be applied to all materials of the general type described with only obvious change in procedures being required to accommodate differences in material composition.
In accordance with the invention, for burning residues which can be burned only with difficulty or which cannot be burned, the residues are continuously fed to the base of a chimney which is preferably vertical, to gether with combustible substances, as hereinafter defined. The burning of the combination is brought on by means of the necessary amount of air at the base of the said chimney. The residues and substances are introduced into the burning zone in pulverized or sprayed form by means of an auxiliary gaseous fluid under pressure, preferably compressed air. This fluid is used under a gauge pressure of at least 0.3 bar., preferably in the range of 0.4 to 5 bar., and thus constitutes an inexpensive pulverizing or spraying means.
The residues subjected to this burning procedure should comprise, or be combined with, at least 30 percent by weight of combustible substances. These substances are fed to a burner together with the necessary amount of air, and undergo substantially complete combustion forming gases or vapors, preferably not harmful ones. These substances may be constituted, in whole or part, by combustible residues to be destroyed with, if need be, a complementary amount of a nonresidual, combustible fluid, preferably an inexpensive one, such as fuel or combustible gas. If no combustible -residue, capable of furnishing a sufficient amount of heat, is available there may be used, as a combustible substance, a nonresidual combustible as above defined. The remainder of the residues fed to the base of the chimney, to be subjected to burning or vaporization, may consist of various substances, water included. It is desirable that the process be applied only to products which, at the operating temperature of the burning apparatus, form only non-harmful gases, vapors and dusts. In the burning apparatus, all the poorly burning residues are subjected to such conditions that all the organic compounds contained therein undergo a complete combustion.
In practice, residues are treated which are capable of flowing either at ambient temperature or at elevated temperature, with or without the help of a stirring device. This definition includes liquid residues which contain solid particles in a suspended state which do not impede regular flow. The viscosity of the residues and combined substances is preferably equal to or below centistokes, and they are fed, separately or together to one or more burners or atomizers" (i.e., injecting devices producing mists of residues and/or substances, and auxiliary gaseous fluid, more particularly air) disposed at the base of the chimney, at which place is provided an air entry. The combustion of the portion of the substances which burns well results in burning or vaporization of the other substances, whether combustible or not, which are contained in the residues being treated.
The process of the invention allows certain sludges containing about 50 to lOO grams per liter of suspended solid particles, to be destroyed. The crosssection of the nozzles for injecting the residues into the burners or the atomizers or injectors should permit passage of comparatively large solid particles which may be present in the residues, so as to avoid any clogging.
- the base of the chimney), and keep up the continuous combustion therein.
The pulverization or spraying of the residues and substances is effected by means of an auxiliary gaseous fluid under pressure, more particularly compressed air. There is no need for any pump to bring these products to the injecting device or devices if there is sufficient liquid head above them to insure the required flow rate in the feeding pipe. Moreover, this pulverization or spraying system favors, through suction, entry of the air necessary for combustion into the lower part of the burning zone. This facilitates starting of the apparatus when cold and a fan for blowing air or removing combustion gases is not required.
In addition to destroying residues, the present invention allows recovery by conventional means of part of the heat evolved by the combustion. The recovered heat may be used, for example, to produce steam, to heat apparatus, to dry products, and so on.
The apparatus of FIG. 1 comprises a chimney l at the base of which are disposed two burners 2 and 3. Burner 2 is continuously fed through a pipe 4 with a combustible substance or substances, as above defined, and burner 3 is continuously fed through a pipe 5 with residue or residues which do not burn or burn only with difflculty. The flow rates of these two feeds are controlled by valves 6 and 7 respectively.
Each burner is connected through a pipe 8 provided with a control valve 10 and through a pipe 9 provided with a control valve 11, to a supply of auxiliary gaseous fluid under pressure, the primary role of which is to atomize" the residues and substances in the form of a mist throughout the burning zone. This auxiliary fluid is fed to the apparatus by a pipe 12.
When the apparatus is running, the combustion of the substances issuing from burner 2 sustains or causes burning and vaporization of the residues issuing from burner 3.
The apparatus of FIG. 2 comprises a chimney 13 having a narrow lower part 14 in the area where the flame of burner 15 springs up. Burner 15 receives through pipe 16, a feed of auxiliary gaseous fluid under pressure. A pipe 17 leads to an injection nozzle (represented in more detail in FIG. 5), extends to narrow part 14, to feed a residue and substance 'mixture to be subjected to burning. Part of these products, for example combustible substances, as above defined, is brought to the apparatus by a pipe 18 provided with a control valve 19, and the remainder, for example residues which do not burn or burn only with difficulty, are fed through a pipe 20 provided with a control valve 21. The mixing of these two kinds of products is effected in pipe 17.
When the apparatus is running, the combustion of the combustible substances at their issuance from the single burner 15 sustains or causes burning or vaporization, in the chimney, of the residues which do not burn or burn only with difficulty.
The chimneys of the apparatus of FIGS. 1 and 2, as well as of any similar apparatus for realizing the process of the invention, may, for example, be made of plate, preferably with an inner refractory covering if such chimneys are designed to be used for a long time.
The apparatus of FIG. 3 comprises a chimney 22 provided at its base with an enlarged burning chamber 23. The chimney and the burning chamber are, for examplc, made of plate and provided with an inner refractory covering 24 and 25. At the bottom of the burning chamber is arranged a burner 26 surrounded by an air entry register 27. The burner, which is similar to that of FIG. 2, receives through pipe 28, a feed of auxiliary gaseous fluid under pressure, a pipe 29 extends to an injection nozzle at its end opening in the burning chamber to feed a residue and substance mixture to be subjected to burning. The working principle of this apparatus is the same as for the above-described structures.
The apparatus of FIG. 4, like that of FIG. 3, comprises a chimney 30, the lower part of which is shown. An enlarged burning chamber 31 is provided preferably with an inner refractory covering 32 and 33. At the bottom of the burning chamber is arranged a burner 34 surrounded by an air entry register 35, these devices being disposed along the vertical axis of the apparatus and at the inlet of a refractory nozzle 36. Burner 34, which is similar to those of FIGS. 2 and 3 receives on the one hand, by a pipe 37, a feed of auxiliary gaseous fluid under pressure and on the other hand, by a pipe 38 which ends to an injection nozzle at its end opening in nozzle 36, a feed of a combustible substance or substances, as above defined, the combustion of which keeps up a permanent flame 39 along the vertical axis of the apparatus.
At the bottom or burning chamber 31 are also arranged several, for example two, injecting devices, preferably disposed symmetrically around the vertical axis of the apparatus, and obliquely, so that their axes are directed towards the heart of the flame 39. These injecting devices 40 and 41, which are similar to the burners of FIGS. 2, 3 and 4, receive on the one hand, by pipes 42 and 43, a feed or auxiliary gaseous fluid under pressure and on the other hand, by pipes 44 and 45, each of which ends to an injection nozzle at its end opening in apertures 46 and 47 of the bottom wall of burning chamber 31, a feed of residue or residues which do not burn or burn only with difficulty. Pulverized or sprayed jets 48 and 49 of this residue or these residues in the form of mist with the auxiliary gaseous fluid are continuously injected into the heart of the flame 39 which sustains or causes their burning or vaporization.
The atomizer, which can be used as a burner or an injecting device, represented in FIG. 5 comprises a body 50 bearing a pipe 51 for the introduction of auxiliary gaseous fluid under pressure, and a pipe 52 for the introduction of residue or residues, and/or of substance or substances, to be burned and/or vaporized, the pipe 52 ending in an injection nozzle 53. Nozzle 53 opens in an outlet cone 54 where the auxiliary fluid and pulverized or sprayed residue or residues, and/or substance or substances, are mixed with one another in the form of a mist. The angle, a, of nozzle 53, and the angle, B, of outlet cone 54, such as represented in the drawing by dash lines, are so chosen as to insure an efficient pulverization or spraying and, for a burner, to give the desired shape of flame.
These angles are 50 degrees and 30 degrees, respectively in the particular embodiment illustrated.
Finally, the burner-injector represented in FIG. 6 is a double-circuit apparatus which allows destruction of substances having no calorific power, by pulverizing or spraying them inside an already developed flame of very high temperature (above l,200C. An advantage of this apparatus is that it performs destruction of noncombustible substances with maximum efficiency. Moreover, the decomposition proceeds more completely and easily without any need to increase the temperature in the burning chamber to values that would damage the refractory materials. The use ofthe burner injector allows simultaneous destruction of immiscible products, with very simple control of proportions. ln particular, the part of this device that provides for the combustion of the substances can be controlled with high versatility, the proportions of combustible substances being used varying as much as times depending upon the particular character of the noncombustible residues being treated.
This burner-injector is essentially constituted by several zones through which fluids are passed, one of these zones being arranged along the axis of the burner injector and the others coaxially surrounding the said zone. This apparatus comprises a device insuring combustion of the combustible substances and a device insuring atomization, or pulverization or spraying, and injection into the flame of residues which do not burn or burn only with difficulty.
The burner device, the role of which is to insure combustion of well-burning substances, comprises a first annular zone 55 surrounding a second annular zone which in its turn surrounds the axial zone. Zone 55 is fed by a pipe 56 with gaseous fluid, more particularly air, under pressure, to insure pulverization or spraying of the substances for their subsequent combustion.
Thus, zone 55 constitutes an introduction chamber for compressed gaseous fluid. About the extremity of this chamber, the gaseous fluid passes through a turbulence ring" 57 shown in detail as FIG 7. This ring causes the gaseous fluid stream to adopt an oblique torsion movement which creates, at the exit from the ring, a turbulence favorable to the mixing of the gaseous fluid with the substances to be burned. These combustible substances are fed to the apparatus by a pipe 58 and pass therein through an annular zone 59 surrounding zone 55. From zone 59, through apertures such as 60 and 61, provided in the wall separating this zone from zone 55, they pass into zone 55 just at the level at which the compressed gaseous fluid issues from turbulence ring 57, and are intimately dispersed throughout this turbulent fluid in this part of zone 55, which plays the role of a mixing chamber. The so-formed mixture of gaseous fluid and substances dispersed throughout leaves zone 55 by passing through a second turbulence ring 62, identical with the first one and, upon exiting therefrom, the substances burn in the combustion zone. The angle of the pulverization cone that gives rise to the flame is determined by the ring 62. A deflector 63, for example made of cast-iron, may be provided around this flame. Such a deflector is represented in the drawing by discontinuous lines.
Preferably this burner" device is fed with "clean" products, i.e., products which do not contain solid par ticles of noticeable size, for example sizes above 0.5 millimeters.
The injector" device, the role of which is to insure pulverization or spraying of the residues which do not burn or burn only with difficulty, is co-axial to and inside the burner" device. It comprises, first, an annular zone 64 surrounded by zone 55 of the *burner device. Zone 64 is fed by a pipe 65 with gaseous fluid under pressure for pulverizing or spraying the residues and, as zone 55 does, constitutes an introduction chamber for compressed gaseous fluid. About the extremity of this chamber, the gaseous fluid passes through a turbulence ring" 66 which is smaller than rings 57 and 62 as shown in FIG. 8. This ring acts upon the gaseous fluid stream as rings 57 and 62 do. The residues to be destroyed are fed to the apparatus by a pipe 67 and pass therein through axial zone 68 which is surrounded by zone 64 and is closed at its upper end by a deflector 69 for the outlet of zone 64, this deflector, for example, having the shape of an inverted cone. From zone 68, through apertures such as 70 provided in the wall separating this zone from zone 64, these residues pass into zone 64 just at the level at which the compressed gaseous fluid issues from turbulence ring 66, and are there intimately dispersed throughout this fluid. The resulting mixture of gaseous fluid and dispersed residues is pulverized or sprayed into the flame resulting from the combustion of the combustible substances, by passage through the annular space comprised between the free end of the outer wall of zone 64 and the deflector 69, the angle of the cone determining the pulverization or spraying angle. Of course, there may be provided a device (not shown in the drawing) to control the position of the deflecting cone with respect to the upper end of the outer wall of zone 64. Such a device may be of conventional type, for example merely a knurled nut acting upon a screw pitch insuring longitudinal displacement of the cone, it being preferably possible to work the said knurled nut while the apparatus is running. This control possibility is useful. as it permits varying the feed rate with a high versatility and of performing, if need by, unpluggings during operation, without taking the apparatus apart.
This injector" device may be fed with any kind of residues whatever, even dirty ones, i.e.," containing solid particles of large size, for example grain sizes up to 3 millimeters, provided, of course, that these particles are movable in the feed pipes.
Operation of the burner-injector of FIG. 6 is commenced by starting the burner device. The substances fed thereto, which are defined as being combustible, kindle at a distance from the outlet of turbulence ring 62 depending upon the composition and flash-point. This distance is generally comprised between 2 and 10 centimeters at the time of starting, when the combustion chamber is cold and slightly diminishes when this chamber becomes hot.
When the chamber is hot, the injector" device is started. The residues which do not burn or burn only with difficulty are pulverized or sprayed outside the apparatus at a distance, for example of the order of about 20 centimeters, above the outlet of turbulence ring 62, thus about 10 centimeters or more above the beginning level of the flame of the burner device. In this manner there is created, around the pulverization or spraying zone of the residues a flaming wall determined by the combustion of the well-burning substances, thus causing gradual and nevertheless rapid decomposition of the said residues by temperatures about 1,200C. while the temperature of the gases resulting from the combustion may be kept at 600 to 800C.
The device intended to insure pulverization or spray ing of the residues is designed, by definition, to treat non-combustible products. However, if the residues which are to be passed through this device are combustible while being dirty," the injector" becomes a burner," and it is not necessary to feed the other burner device with combustible substances if the combustion at the end of the zone 64 is self-sustaining.
The turbulence rings represented in FIGS. 7 and 8 are constituted by equal sections of hollow tubes, such as 71, 72, 73, 74, cut so as to form parallel bevels at their two ends, these fragments being obliquely inclined and arranged side-by-side to form an annular bundle so that the bevelled sections are within two parallel planes, A-B and C-D, E-F and G-H, delimiting, respectively, the upper and lower surfaces of the ring. The sections are soldered, each one with its two neighbors, laterally in this position, along two generatrices almost diametrically opposite, and the so-constituted ring is closed. In this way, it forms a crown traversed by a circular series of oblique passageways (outlet orifices such as 75, 76 and 77).
As non-limiting examples, the process and apparatus of the present invention can be used successfully to burn and vaporize the following industrial residues or substances or similar ones:
1. As residues which do not burn or burn only with difficulty, any one of the following industrial byproducts:
Decantation sludges from filtration juices of solid chemicals Industrial residual waters which may have a high content of polluting substances, whether watersoluble or not, more particularly organic Bacterial sludges coming from a unit of biological purification of residual waters Emulsions recovered by decantation or flotation from industrial residual waters Solid residues that are soluble in water or in the byproducts or products specified above or below Exhausted, water-soluble cutting oils, etc.
2. As combustible residues, as above defined, any
one of the following industrial by-products: Contaminated solvents, diluents or auxiliary liquids Distillation or other worthless by-products Exhausted sump oil, etc.
Of course, it is possible to treat together more than one of the residues of any of the two above-indicated groups.
Still, of course, care should be taken that the residues to be treated and mixtures thereof do not give rise to dangerous or troublesome chemical reactions.
Moreover, as aforesaid, it is possible to use as a combustible substance a non-residual combustible, preferably an inexpensive one such as low cost heating oil, which may be wholly or partly substituted for combustible residues.
The following examples, which are merely illustrative and in no way limiting, show some applications of the process and apparatus of the present invention.
Example 1 Using an apparatus of the type illustrated in FIG. 1, having a chimney 1 made of plate with an inner refractory covering, the said chimney being 3 meters high and having an internal diameter of 40 centimeters, there was treated l50 liters per hour of oily emulsions of varying composition which contained up to percent by weight of water and 10 percent by weight of organic or inorganic solid substances. The emulsions came from a unit for purification of residual waters from organic chemical processing, together with 80 liters per hour of by-products of organic chemicals manufactured, the said by-products having a lower heating power" above 7 thermies per kg. The apparatus is fed through pipe 12 with 60-70 normal cubic meters per hour of air under a gauge pressure of 4-5 bar. The temperature in the chimney during the burning operation is about 1,200C. The residues are entirely destroyed, without smoke formation.
It should be emphasized that the oily emulsions so destroyed cannot be destroyed by burning in pits. As a matter of fact, their destruction is expecially difficult because of both their high water content (which, in certain layers of these emulsions, is as high as 80 percent by weight) and their very high viscosity and thixotropy. The process of the present invention is perfectly capable of insuring their complete destruction.
Example 2 An identical result is obtained by treating similar resi dues in the apparatus of FIG. 2, in which the atomizer is adapted to work with compressed air under a gauge pressure of 0.4 bar.
EXAMPLE 3 Utilizing a "burner-injector" device of the type represented in FIG. 6, arranged under a chimney in a burning chamber having the same general shape as those of FIGS. 3 and 4, but, of course, without the apertures 46 and 47 of FIG. 4 and the corresponding items, there was treated 500 liters per hour of residual waters having a high content of organic substances, together with to I50 liters of combustible residues having a lower heating power" of 7 thermies per kg, (e.g. sump oil). The temperature of the bases and vapors discarded in the atmosphere by the apparatus varies between 600 and 850C.
When the products so destroyed yield ashes, the latter settle in the lower portion of the burning chamber from which it is easy to remove them by periodically stopping the run of the apparatus, or else during the run of a suitable device such as, for example, a trap, for ash removal, has been provided in the bottom of the burning chamber.
It will be understood that various changes and modifications may be made in the above described invention which provide the characteristics of this invention without departing from the spirit thereof particularly as defined in the following claims.
That which is claimed is:
1. An apparatus for destroying or eliminating through burning or vaporization, industrial residues comprising viscous liquids capable of flowing regularly and being substantially non-combustible, in combination with at least percent by weight combustible substances, said apparatus comprising a substantially vertical chimney, a base for said chimney, and at least one burner associated with said base, means for feeding an auxiliary gaseous fluid under pressure to said burner, means for directing said combustible substances to said burner along with said gaseous fluid, and means for feeding said residues to said burner along with said gaseous fluid, said burner comprising an annular zone fed with gaseous fluid under pressure at one of its ends, and containing at its opposite end, two turbulence rings, separated from one another by a mixing zone, the outlet of the second turbulence ring opening into a combustion zone; and a second annular zone surrounding the first one and being fed with said substances at its end situated on the same side as the gaseous fluid feed point to the first annular zone and at its opposite end with apertures at the outlet level of the first turbulence ring, said apertures allowing intimate mixing of the substances with the gaseous fluid before the resulting mixture passes into the combustion zone through the second turbulence ring; and a device insuring spraying and injection into the flame of non-combustible residues, said device comprising a third annular zone and an axial zone, said third zone surrounding said axial zone, said third zone having one end situated adjacent the feed points of the other zones and the opposite end of said axial zone being located adjacent the outlet of said third zone, a deflector connected to said opposite end and defining apertures opening into said third zone.
2. An apparatus in accordance with claim 1 wherein said deflector which closes the end of said axial zone has the shape of an inverted cone.
3. An apparatus in accordance with claim 2 wherein the position of the deflector with respect to the free end of the outer wall of said third zone is adjustable.
4. An apparatus in accordance with claim 1 which further comprises a second deflector surrounding the flame in the combustion zone.
5. An apparatus in accordance with claim 1 wherein said turbulence ring comprises equal fragments of hollow tubes, cut so as to form parallel bevels at their two ends, the said fragments being obliquely inclined and arranged side-by-side to form an annular bundle so that the bevelled sections are within two parallel planes delimiting the upper and lower surfaces of the ring, the said fragments being connected, each one with its two neighbors, laterally in this position, along two generatrices substantially diametrically opposite, said ring being closed.
6. In an apparatus for destroying or eliminating through burning or vaporization, industrial residues comprising viscous liquids capable of flowing regularly and being substantially non-combustible, in combination with at least 30 percent by weight combustible substances, said apparatus comprising a substantially vertical chimney, a base for said chimney, and at least one burner associated with said base to provide a combus tion zone in the area of the base, the improvement comprising first conduit means leading to said burner, means for feeding a gaseous stream under pressure into said first conduit means, second conduit means for said combustible substances, outlet means defined by said second conduit means for passing the combustible substances into contact with said gaseous stream for pulverizing said substances whereby the pulverized substances and admixed gaseous streams are fed to the burner, and third conduit means for said residues, outlet means defined by said third conduit means for passing said residues into contact with said gaseous stream for pulverizing said residues whereby the pulverized residues and admixed gaseous stream are fed into the flame developed by the burner in the combustion zone, and including at least one turbulence ring in said first conduit means for agitating the gaseous stream.
7. An apparatus in accordance with claim 6 wherein said first conduit means comprise a pair of conduits for feeding a gaseous stream into contact with said substances and said residues, respectively, and including separate turbulence rings associated with said first and second conduits, said rings being positioned for the passage of admixed material through the rings immediately prior to entry into the combustion zone.
8. An apparatus in accordance with claim 6 wherein said third conduit means is disposed substantially along the axis of the apparatus, said first and second conduit means comprising annular zones positioned in surrounding relationship relative to the first conduit