DE2538134A1 - OIL BURNER - Google Patents

Description

Meissner & Meissner

PATE NTAN WALTS OFFICE

BERLIN - MUNICH * \ Γ O O 1 ^ J /

Zt! OH

PATENT LAWYERS

DIPL-ING. W. MEISSNER (BLN) DIPL-ING. P. E. MEISSNER (MCHN) DIPL-ING. H.-J. PRESTING (BLN)

1 BERLIN 33, HERBERTSTR. 22nd

? 5 ΔΙΙΓ 19? 5

Your reference Your letter from our logo Berlin, the · Π ·

50-1122

MITSUBISHI JUKOGYO, Kabushiki Kaisha 5-1, Marunochi 2-chome, Ohiyoda-Ku, Tokyo, Japan.

Oil burner

The invention relates to improvements in oil burners.

Usual oil burners are shown in FIGS. In them is a burner with an inner cylinder 02 in the center of the burner and an outer cylinder 01 is shown which is coaxial with the inner cylinder. At the front end The burner has several oil injection valves 04, each of which is surrounded by an air vortex 05.

The outer and inner cylinders are with multiple air combustion holes 013 provided. The air will burn through the vortex 05, a central vortex 06 at the rear end of the inner cylinder 02 and the air holes 013 of the Inner and outer cylinders 01 and 02 are introduced into the combustion chamber and the resulting air flows run in the direction indicated by the arrows in FIG Establishments »

609811/0895

BDRO MONKS: TELEX: TELEGRAM: PHONE: BANK ACCOUNT: CHECK ACCOUNT: β MONKS 22 1-856 44 INVENTION BERLIN BERLINER BANK AQ. W. MEISSNER, BLN-W ST. ANNASTR. 11 INVEN d BERLIN 030/885 60 37 BERLIN 31 122 82-109 TEL: 089/2285 44 030/886 23 82 3695716000

Drops of liquid fuel from the oil injection valves 04 mix with the air that has entered through the vortices 05, 06 and the air holes, thus creating a continuous combustion zone 014 _{or the like}

This common two-cylinder burner has the following disadvantages:

1J Since several oil injection valves 04 are located between the concentric cylinders, each pair of adjacent valves gives an interfrequency with the eddy current and thereby reduces the vortex effect. As shown by curves A and B in Figure 3, with the double cylinder burner the degree of combustion efficiency is greater when the vortex angle is 0 through the "vortex 45 ° is as if it is 35 °. The vortex with the Vortex angles of 45 ° are therefore preferred in many cases been. As Figure 4 shows, the smoking characteristic is the most desirable when the swirl angle is between 30 ° and 35 °. Nevertheless, in most cases the vortex had to be at an angle of 45 °, which gives a good degree of combustion efficiency, can be used at the expense of the smoke characteristic.

2 ·) The large number of air holes 013 »the consecutive Are arranged over a long distance on the rear side of the gas inlets, result in a corresponding long burn zone. Furthermore, the penetration of the air nozzles is limited and the air-fuel mixing is limited is insufficient, which increases the smoke and NOX content of the exhaust gas. (See Figure 5)

3.) In a V _e rsuch to control the smoke and NOX -

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Emission has been proposed to give a large amount of air around the injectors 04 around the air-fuel -Ratio increase.

The object of the invention is to eliminate these disadvantages of the previous devices and to specify an oil burner, which can reduce both smoke and ITOX emissions.

The features of the invention are as follows:

1.) Many oil injectors are on the top of one annular space between the inner and outer cylinder provided, and an air beer to circulate in the same direction is attached around each valve .

2.) An air beer to circulate in the opposite direction is located at the inner end of the inner cylinder O

3.) Several air holes, each of which is provided with a grommet, are located in the wall part of the outer cylinder, surrounding the inner end part of the inner cylinder.

4.) Dilution of the air holes, each of which is provided with a nozzle, is located in the wall part of the outer cylinder at a distance not less than the diameter of the cylinder behind the air holes, which have been described under 3 »,

5.) There is a water supply device for burning heavy fuel oil intended,

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According to the invention, the following is carried out:

A) The primary combustion zone is limited to the annular space. The burning of rich mixture takes place by supplying air in a ratio (i.e. the ratio of the amount of air supplied to the theoretical air volume) of not more than 40% only by the vortex mentioned under 1.

B) Air is introduced into the rear combustion chamber via the vortex from 2. and the air holes from J. Swirlers and air holes are located in places where combustion flames leak out with rich mixture, so that the addition of air at a ratio of not more than 0.4- the total ratio up 1.05 to 1.30 increased. With the excess air, the gas with a large unburned content will turn burned under a lean mixture. Where more air is needed, there is a third zone for rapid cooling (or a dilution zone) provided so that the Gas is diluted to regulate the NOX formation.

0) A, reducing atmosphere can be in the burning zone the lean mixture can be made by adding moisture. This increases the efficiency the gasification and the NOx and smoke emissions are reduced.

The invention is intended to find wide applications, for example in boilers and gas turbines. For use with The device according to the invention can be used in boilers which operate with low proportions of excess air either close their dilution zone holes or with of the zone itself · Conversely, if the An j

1/6

part of excess air such as a gas turbine is high, the gas in the device after the Invention can be cooled to any desired temperature in the dilution zone.

The invention has the further features and advantages:

1.) An even number of injectors are in one Circle arranged at the top of an annular space. A vortex of air is arranged around each valve and the individual fuel injection air swirl systems (here referred to as "burner") are arranged so that the vortex of each plant or each burner circulates with a vortex angle opposite to that of the neighboring burner and thereby a disturbance of his Excludes air vortex with the neighboring.

2.) The even number of burners varies in the capacity of the injectors or the air swirlers or in both. I.e. the burners that operate at a high or low ratio of delivered to theoretical Air or working with a lean or rich mixture are arranged alternately. This increases the ignitability and improves the combustion stability.

The invention also has the following advantages:

1.) To avoid interference from neighboring ones Air vortex is any injector surrounded by an air beer with a separator from a conical, cylindrical one or conical-cylindrical shape in the combustion zone near the respective valve.

2.) A vortex angle (O = 30 to 35 °) cLer <üe at most provides desired smoke characteristics is combined with feature 1. to increase combustion efficiency and smoke and NOx characteristics to improve.

3.) In the independent combustion zones, those of the separators and the neighboring injection systems are formed, the combustion states of rich and poor air-oil mixtures are alternately cyclical Arrangement. As a whole, an air-oil mixture with higher combustion efficiency (the usually the NOx emission increases) and thus the combustion according to the invention produces less NOx.

4-.) The cyclical combination of rich and lean mixtures ensures good ignitability and combustion stability and thus stable operation.

These and other objects, advantages, and features of the invention are discussed in conjunction with illustrations explained by training examples. In the drawings is:

Figure Λ a longitudinal section through a conventional oil burner on the line II of Figure 2;

Figure 2 is a cross section on the line H-II of Figure 1;

FIG. 3 is a diagram of the combustion efficiencies of FIG Oil burners in relation to whirl angles;

Figure 4 is a diagram of the smoke characteristics of 01 burners with respect to the vertebral angles;

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Figure $ is a graph of the relationship between ITOx concentration and the air ratio;

FIG. 6 shows a longitudinal section of a burner according to the invention on the line III-III in FIG. 7;

FIG. 7 shows a cross section on the line IV-IV of FIG. 6;

FIG. 8 is a longitudinal section of another burner according to the invention on the line V-V of FIG

FIG. 9 shows a cross section on the line VT-VI of FIG. 8;

FIG. 10 is a longitudinal section of a further burner according to the invention; and

Figure 11 is a longitudinal section of yet another burner according to the invention.

Figures 6 and 7 show an outer cylinder 1 and an inner cylinder 2, which is coaxial in the front seam of the outer cylinder 1 is arranged. The two cylinders form an annular space between them 3 Several oil injectors 4- are evenly on a circle arranged distributed at the front end of the room 3. The same number of vortices 3 are used for the primary combustion air each lying around a valve and turning their leaves in the same direction. At the rear At the end of the inner cylinder 2 there is a vortex 6 for the secondary combustion air, the blades of which are in act in the opposite direction »For the secondary air several holes 7 go through the wall part of the outer cylinder 1 through which the rear end of the inner

nenzylinders 2 surrounds. Each hole is with a grommet

8 provided. Same holes 9 for the dilution air are behind in the outer cylinder at intervals not less than the diameter of the outer cylinder the secondary combustion air holes 7. Each hole 9 is provided with a grommet 10. Near the vortex for the secondary combustion air there is a water or steam injector 11. A water - or Steam supply pipe is at one end with the injector 11 and at the other end with the outlet of a not shown Pump connected.

On the walls of the outer cylinder 1 and the inner cylinder 2 there are no holes except for the secondary combustion air holes and the holes

9 for the dilution air at certain points and also of air hole loops, not shown, for cooling of the walls.

Simultaneously with the introduction of liquid fuel from the injectors 4, the primary combustion air swirlers deliver 5 »which surround the individual valves, Air for combustion in a combined amount not less than 40% of the theoretical for combustion required air volume.

On the other hand, the vortex 6 and the holes 7 for the secondary combustion air supply air, which is combined with of the air of the vortex for the primary combustion air an amount of 1.05 to 1.30 times the theoretical Air is. If the total call exceeds 1.30 t ratio, the remaining air is supplied through the holes 9 for the dilution air. When using heavy fuel oil is added water or steam from the injector 11.

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The device works as follows:

In the annular space 3 which is not supplied with more than 40% of the theoretical amount of air of the agitators 5 of the primary combustion air ₅ is a zone 151 in which the gaseous mixture having a high fuel concentration burns incompletely. In this zone, the unburned part of the liquid fuel is gasified by heat.

Around the inner end of the inner cylinder 2 is a ' large amount of fresh air from the swirler 6 for the secondary combustion air to the associated holes 7 for incompletely burned gas added. Thus, in the space behind the inner end of the inner cylinder 2 a zone 16 in which a gaseous mixture with a low fuel concentration is completely burned should be (right in Figure 6).

Since the direction in which the blades of the vortex 6 for the secondary combustion air circulate, towards ^ of the blades of the swirler 5 for the primary combustion air is opposite, the fuel gas mixes in those generated by zone 15 of the primary combustion Eddy currents work well with the fresh air.

Also because the holes 7 for the secondary combustion air run concentrically to the inner end part of the inner cylinder 2 with the help of the grommets 8, is the point in time the air penetration to the central axis is so great that air and oil are mixed well.

Water or steam supplied from the injector 11 is

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guided by the combustion air currents, where they build up a reducing atmosphere. From the holes 9 for the dilution air, air is supplied, whereby their penetration is increased by the spouts.

It mixes with the combustion gas from the secondary combustion zone and rapidly cools the gas.

The working of the device described offers the following advantages:

1.) Since several injection valves 4- for one annulus 3 are provided and each valve is equipped with a swirler to effect combustion with rich mixture is, will

a) the ignitability and combustion stability improved,

b) kept the combustion temperatures low and the NOx formation reduced (Figure 5)? and

c) Air and fuel well mixed and, if richly mixed, the flame is limited in this zone.

2.) The fuel gas mixes with the air from the swirler 6 in the inner end of the inner cylinder 2 and from the air holes 7 of the outer cylinder through. The resulting mixture burns under lean mixture conditions. This allows carbon and unburned oil from the primary combustion zone under lean conditions Burn mixture. As a result, smoke is reduced and ITGx emissions are kept low (Figure 5) ..

3.) Because HoO is delivered along with the vortex air currents water droplets are released into the outer area of the

e-09811/0696

combustion chambers blown. In this way, the Hydrocarbon of fuel through Η ~ 0 to CO or GOp and Hp decomposed, resulting in gasification of the fuel coming soon. Since the reaction is endothermic, air must usually be supplied and the unburned Part and the carbon from the primary combustion zone are burned again, so that the resulting Heat is used «With the device according to the invention, this reaction heat is used for gasification and for Reduction of smoke and NOx emissions while improving fuel quality.

4-.) When burning with a lot of excess air, a Dilution zone at the rear end of the secondary dilution Combustion zone is added and all remaining air is used for rapid cooling. This shortens the dwell time of the hot gas and reduces the NOx emission.

While the injection of water or steam in the example described takes place through a nozzle, the liquid that flows in from a ring pipe together with the air from the air holes in a ring pipe the cylindrical combustion chamber is given alternately the water or the steam in the liquid premix and the injectors can inject the mixture instead of oil alone.

Figures 8 and 9 show an even number of injection valves 4-a, 4-b which are distributed on a circle at the front end of the cylindrical space 3 with an annular cross-section. The valves 4-a, 4-b are corresponding to the primary combustion air swirler 5 ^a ? 5b, the leaves of which are in opposite

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alternate directions, i.e. the vortex blades 5a, 5b roll in opposite directions

Except for the above, the embodiment of Figures 8 and 9 has the same construction like that of the exemplary embodiment according to FIGS. 6 and 7. In all figures, the reference symbols denote the same or equivalent parts.

The injection valves 4a, 4b or the swirlers 5 ^a ? 5b for the primary combustion air or both together vary in capacity so that each pair of adjacent valves or vortices has different capacities. That is, those that treat air in a high and low ratio of the supplied and theoretical air are arranged alternately. This means that the burner, each comprising a valve 4a and a swirler 5a, has an air-fuel ratio which is not similar to that of the burner from FIGS. 4b and 5b.

The second works with the construction described Embodiment in the following way:

The liquid fuel injected from the injection valves 4a, 4b is mixed with the combustion air, the vortices assigned by the valves 5a »5b for the primary combustion air supplied is burned. There is a primary combustion zone 15 in the annular space 3 · Here the air conditions are such that a given Burners have an air ratio of not less than 0.4 and neighboring burners have a ratio of not use less than 1.4.

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On the other hand, the swirler 6 and the hole 7 deliver the secondary combustion air a large amount of fresh air and result in a secondary combustion zone 16, in which the combustion is ended.

With a total air ratio above 2.0, the remaining air is through the dilution air holes 9 in the Combustion chamber directed.

In the case of heavy fuel oil or the like, either water is used or steam from the injector 11 is added.

The combustion flames are thus in the primary combustion zone of lean or rich mixtures enclosed by airflow cones that intermingle swirl in opposite directions, generated alternately in a circular arrangement. With gradual downward movement the flames begin to merge. In the secondary combustion zone, a strong vortex air flow presses which is supplied by the vortex 6 for the secondary combustion air, the group of small vortex flames so that they whirl together. At the same time, air flows through the holes 7 cLer secondary combustion air of the outer cylinder introduced. These currents excite with their penetration, which is amplified by the nozzles 8 is, the group of small vortex flames. In the described In this way, the small flames are strongly mixed in and out. Then the unburned part becomes the The rich mixture is burned and the exhaust gas serves as part of the combustion air. This total air ratio in the two combustion zones can range between 1.5 and 2.0. When the air volume is above this Area, there is rapid cooling with air

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flowing through the dilution air holes 9 with as great a moment of air penetration as possible will be delivered «

With this construction the following advantages result for the above embodiment:

1.) As with swirling air currents the vortex, the side arranged side by side, the individual subdivided flame vortices (in flames of lean and rich mixtures) are generated in the primary combustion zone, extremely good ignitability and combustion stability are obtained and there can be zones of air-fuel ratios used for low NOx production (the zones of lean and rich mixtures according to Figure 6). First of all, the fuel from the burners of the rich mixture is ignited and the resulting Flames serve as pilot lights to ignite the gaseous mixture from the burners of the lean mixture and then the stresses on both are increased. Meanwhile, there is no instability such as a blowout on.

2.) In the secondary combustion zone, the group of small vortex flames becomes circular in formation from the primary combustion zone by the internal vortex airflow and by air currents moving through which pass through the flames from the outside. A stream of uniform gas mixture is thus obtained and the unburned content (mainly carbon) of the rich mixture is burned again. aside from that the recirculation combustion effect of the exhaust reduces smoke and HOx emissions, resulting in cleaner gas generation leads"

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FIG. 10 shows a further exemplary embodiment of the invention, which has an outer cylinder 101 and an inner cylinder 102 contains. The inner cylinder is shorter than the outer cylinder and is coaxial with the front one Space of the outer cylinder, so that an entrance space 105 between them results. There are several injectors 104 evenly distributed and circular on the front End of the annular space 103 attached. The primary combustion air vortex 105 are located around the individual valves. These vortices have one Vortex angles from 30 to 35 ° · Separator 106 in the mold of cylinders, cones or their combinations are each attached and run around the vortex 105 in the direction of flow.

On the outside and inside of each divider there are ring-shaped air passages and, an outer vortex can be provided in addition to the inner vortex be. A secondary combustion air vortex 107 is located at the rear end of the inner cylinder 102. A plurality of secondary combustion air holes 108, each of which is provided with a grommet 109, is located in the wall part of the outer cylinder 101 which surrounds the rear end of the inner cylinder. Multiple dilution air holes 110, which are provided with grommets 111, go through the wall part of the outer cylinder 101 in smaller ones Distances than the diameter of the cylinder behind the secondary combustion air holes 108.

The capacity of the injectors 104, or that of the swirlers 105, or both, vary so that each pair Adjacent valves or vortices have different capacities, or, those of them, the air in large

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and small ratios of the delivered to the theoretical amount of air (air ratio) are arranged alternately.

The operation of this embodiment is as follows:

The fuel injected from the injectors 104 becomes with that from the primary combustion air swirlers 105 air supplied around the valves is burned and results in a primary combustion zone in annulus 103. In this case the air conditions are such that a given burner has an air ratio of, for example, no more than 04, and the neighboring burners a ratio of not less than 1.4 is used.

In the meantime, the whirlers 107 and 108 are delivering a large one Amount of fresh air and form a secondary combustion zone in which the combustion is completed.

When the total air ratio is above 2.0, the remaining air is released through the dilution air holes 110 in introduced the combustion chamber.

This embodiment has the following advantages:

1.) Because the dividers 106 rims around the valves 104 and their combustion air swirler 105, each system is made up of a swirler and a valve a combustion independent of the other systems in the annulus 103. The burn near every valve that controls smoke and NOx production is dated

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Rest isolated. In other words, near each injector, combustion occurs independently without interference with the swirling of the neighboring vortices and the so subdivided flames arise in the primary combustion zone. Thus, a vortex angle, .der in relation to the degree of combustion and smoke characteristics has the best effect, according to Figures 3 and 4 (e.g. θ = 35 °). While the degree of combustion of the ring burner for a vortex with an angle of 35 °, according to the invention, the combustion efficiency can be increased while the smoking characteristic is sufficiently kept like the curve C in Figure 3 shows.

2.) In the secondary combustion zone, the group of small vortex flames becomes the ring-shaped in the primary Combustion zone are created by the eddy currents of air penetrating from the inside and from the outside Air currents mixed up. The unburned part (mainly carbon) of the thus obtained rich Mixture is burned again, while at the same time the NOx production through the exhaust gas re-running effect is decreased.

3.) When burning with a lot of excess air, all of the remaining air will pass through the air holes of the dilution zone supplied, which are intended for this occasion, so that the combustion gas quickly with the Air is mixed and cooled and the residence time of the hot gas is shortened in order to reduce the BOx emission .

Yet another embodiment (of the ring type)

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is shown in FIG. The inner cylinder 202 is in Outer cylinder 201 received coaxially and results in a cross-sectionally annular space 203 between them and the outer cylinder.

Several injection valves 204 are located on a circle at the front end of the annular space 203.

Primary Combustion Air Swirler 205, each of which arranged around each valve have a swirl angle of 30 to 35 °.

Separators 206 of cylindrical, conical or conical-cylindrical shape are each around the vortex 205 arranged, and run in the direction of flow. Inside and outside of these separators are located Passages * with an annular cross-section.

Several secondary combustion air holes 208, γοη those each is provided with a grommet 209, go through the wall part of the outer cylinder in a certain Distance from the valves 204 through .. Here, too, there are several air dilution holes 210 which are provided with spouts 211 and through the wall parts of the outer cylinder and the inner cylinder 202 go through at locations that are further behind the secondary Combustion air holes 208 lie.

The capacities of the fuel injectors 204 and / or the primary combustion air vortex 205 vary between adjacent valves and vortices. In other words, those at low and appropriately high ratios of the amount of air supplied to the theoretical work are alternating

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arranged. This example has the same punctures and advantages as the one already in connection with the Figures 8 and 9 described on.

The invention shows an oil burner of high industrial strength Significance with applications in continuously operating incinerators, boilers, gas turbines, etc.

- claims

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609811/0895

Claims (5)

Patent claims: (1, / oil burner with a double concentric combustion cylinder, which has an outer and a concentric and shorter inner cylinder, wherein the inner cylinder is located in the front part of the space and "extends axially, so that it is an annular space forms between itself and the outer cylinder, characterized by several fuel injection valves (4-), which are arranged on a circle on the upper part of the annular space (3), by combustion air vortex (5) » which are each arranged around the valves (4-) with the same swirl angle in a given direction, by another combustion air vortex (6) at the inner end of the inner cylinder (2) and with one Vortex angle in the opposite direction to that of the first and through several air holes (7) in the wall part of the outer cylinder (1), which surrounds the inner end of the inner cylinder (2), and also in the wall part of the outer cylinder (1) at a distance of not less than the diameter of the outer cylinder behind the first air holes (7). 0 9 8 11/0695 - 21 - 2. Burner according to claim 1, characterized in that the holes (7) are each provided with a nozzle (10) _o 3 · Burner according to claim 1, characterized in that each burner system consists of an injection valve (4-) and -the associated swirler (5) in the capacity of the valve and / or vortexes so different from the one or those of the neighboring systems that those involved in h, öh.en and at low ratios the delivered are arranged alternately to the theoretical amount of air, and that the air holes (7) each with a spout (10) are provided. 4 ·. Burner according to Claims 1 and 3 »characterized in that that means for introducing moisture and adding water or steam to the combustion air located in the inner cylinder. 5. Burner according to the preceding claims, characterized in that combustion air vortices are arranged around the injection valves, and separators of cylindrical, conical or conical-cylindrical shape are arranged around the vortex so that each separator around each system of valve and associated vortex provides an edge, and the vortex in the flow space is axially open in the direction of flow from the valve to allow air to flow for primary combustion from the inside and outside of each separator and that the capacity of each valve and / or the associated vortex of is so different from the neighboring one that ai , valve-vortex-systems, which are arranged alternately at high and low ratios of delivered to theoretical quantities. Dipl.-Jngy 0 9 3 11/0895 e e r s e i f e