JPH0484006A - Liquid fuel burner - Google Patents

Abstract

PURPOSE:To evaporate and vaporize the liquid fuel at a relatively low temperature and supply the gaseous fuel to combustion by providing a liquid fuel dripping means which atomizes the liquid fuel and drips it in the upper section of an evaporation chamber and directly evaporating the dripping fuel by the ascending air flow developed by the heated air. CONSTITUTION:At the upper ceiling section of an evaporation chamber 11, a fuel tank 21 and a plurality of hollow needles 22 as a liquid fuel dripping means are provided. The hollow needles 22 project from the bottom of the fuel tank 21 towards the evaporation chamber 11, and they also project into the fuel tank 21 by the height of H. The liquid fuel in the fuel tank 21 is dripped in small particles through the small holes in the hollow needles 22 to the evaporation channel 11. The air that is heated by a heater 15 is led to the evaporation chamber 11 through an introduction pipe 12, and flows upwards as an ascending air flow. The liquid fuel that is dripped as small particles from the hollow needles 22 makes contact with the ascending air, and is evaporated and vaporized. And, the fuel becomes a mixture gas and is sent to the combustion section 143 through a discharge pipe 13 and there it burns.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention provides a fuel combustion device in which liquid fuel such as petroleum is directly evaporated and vaporized at a relatively low temperature using heated air, and is then combusted. Regarding.

<Prior Art> The present applicant has already disclosed in Japanese Patent Application No. 1-302965, etc., an apparatus for supplying liquid fuel into heated air, evaporating it directly at a relatively low temperature, and combusting it. A device using an airless jet nozzle was provided. This device is shown in Figure 5 (A).
This will be explained using (B). FIG. 5(A) is an overall configuration diagram of a conventional device, and FIG. 5(B) is a sectional view taken along line DD in FIG. 5(A). Air is taken in by a fan l and sent through a supply path 2 into an evaporation chamber 3. 4 is an electric heater for heating the air midway. On the other hand, liquid fuel such as petroleum is ejected into the evaporation chamber 3 in an atomized state through the ejection nozzle 5 . Then, the liquid fuel atomized in the evaporation chamber 3 is brought into direct contact with the heated air, evaporates and vaporized, becomes a mixture with air, and is sent to the combustion section 6 for combustion.

<Problems to be Solved by the Invention> However, in the above-mentioned conventional technology, the jet nozzle 5 is used and the liquid fuel is atomized using high pressure, so the opening at the tip of the nozzle 5 becomes very small, and foreign matter such as dust can be removed. A nozzle with a small flow rate (17!/hour) in order to avoid clogging due to this problem had the disadvantage that it could not be put to practical use.

Further, even if an attempt is made to change the spray flow rate by changing the pressure applied to the injection nozzle 5, there is a drawback that a large aperture ratio (T, D, R) cannot be achieved because the flow rate is the square of the pressure.

Furthermore, when spraying with the injection nozzle 5, the spray spreads at a certain angle, tends to hit the inner wall surface of the evaporation chamber 3, and has the disadvantage that it tends to condense on the wall surface.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a liquid fuel combustion device that can eliminate the drawbacks of the conventional devices described above, and that can directly evaporate liquid fuel at a relatively low temperature and use it for combustion.

<Means for Solving the Problems> In order to achieve the above object, the liquid fuel combustion device of the present invention causes granulated liquid fuel to contact and explode directly with heated air in an evaporation chamber, and the resulting mixture A liquid fuel combustion device is provided in which liquid fuel is sent to a combustion section for combustion, and a liquid fuel dripping means is provided above the evaporation chamber to finely drop the liquid fuel, and the liquid that drips from the means is provided. It is characterized by a structure in which the fuel is directly evaporated by the upward current of heated air.

<Operation> Fine particles of liquid fuel falling from above the evaporation chamber are brought into direct contact with heated air blowing up from below, and are evaporated at a relatively low temperature. A mixture of fuel and air is then sent to the combustion section where it is combusted. The fine particles that are dropped have a larger diameter than when using a conventional injection nozzle, so some particles may not be completely evaporated, but they can be collected below the evaporation chamber and reused. By using liquid fuel dripping means instead, small flow rates (
11/hour or less), no nozzle clogging occurs. Further, the range of the aperture ratio of the dripping flow rate can be increased. Further, since the liquid is not sprayed at a fixed angle as in the case of an injection nozzle, condensation of the evaporated fuel on the inner wall of the evaporation chamber is also reduced.

<Example> FIG. 1 is an overall configuration diagram of an apparatus for implementing the present invention, FIG. 2 is a partial detailed view of the apparatus for implementing the invention, and FIG. 3 is a plan view of the apparatus for implementing the invention.

An evaporation chamber 11 is provided within a vertically long cylindrical container 10.

A heating air introduction vibe 12 is connected to the lower side wall of the evaporation chamber 11, and a delivery pipe 13 for guiding the air-fuel mixture to the combustion section 14 is connected to the upper side wall of the evaporation chamber 11. The heated air is sent by a blower fan (not shown), heated by a heater 15 on the way, and then passed through an introduction pipe 12 to the evaporation chamber 11.
and becomes an updraft.

An oil tank 21 and a plurality of hollow needles 22 are provided on the upper ceiling of the evaporation chamber 11 as liquid fuel dripping means. The oil tank 21 includes an oil feed pipe 25 that communicates with an oil feed pump 24 that supplies liquid fuel from an oil level regulator 23;
A return pipe 26 is connected to prevent the oil tank 21 from overflowing. Further, an unevaporated fuel collecting section 16 is provided at the lowermost end of the evaporation chamber 11 to receive liquid fuel that has not been evaporated in the evaporation chamber 11 and return it to the oil level regulator 23 through a collection pipe 17. ing.

The hollow needle 22 is for dropping liquid fuel from the oil tank 21 into the evaporation chamber 11, and protrudes from the bottom of the oil tank 21 toward the evaporation chamber 11, and also protrudes into the oil tank 21 by a height H. ing. The liquid fuel in the oil tank 21 is dripped into the evaporation chamber 11 through a narrow hole in the hollow needle 22.

The air heated by the heater 15 is guided into the evaporation chamber 11 from the introduction vibe 12 and flows upward as an upward air current.

On the other hand, liquid fuel is previously supplied to the oil tank 21 by a height H up to the upper end of the hollow needle 22, and new liquid fuel sent from the oil pump 24 is fed from the upper end of the hollow needle 22. A liquid level is formed at a height h. When the height h becomes high enough to overcome the passage resistance of the hollow needle 22, the liquid fuel starts to fall from the lower end of the hollow needle 22 in the form of droplets. If the hollow needle 22 is attached to the oil tank 21
If it is attached to the bottom of the oil tank 21 instead of protruding inward, the distance between the entrance of the oil pipe 25 to the oil tank 21 and each hollow needle 22 is not constant, so that dripping occurs at the initial stage or end stage of fuel supply. There are hollow needles 22 that are dripping and hollow needles 22 that are not dripping, causing transient characteristics in the fuel supply. Since the hollow needle 22 protrudes into the oil tank 21, fuel is supplied to the evaporation chamber 11 from the oil tank 2.
This is converted into an up and down movement of the liquid level, and each droplet 22 starts and stops dropping at the same time.

The liquid fuel dripping from the hollow needle 22 in the form of fine particles comes into contact with the rising heated air and is evaporated.

Then, it becomes an air-fuel mixture and passes through the sending vibe 13 to the combustion section 1.
4 and burned.

The inner diameter and number of the hollow needles 22 can be arbitrarily designed depending on the scale of the apparatus and the like.

Note that the droplet dropped from the hollow needle 22 has a larger diameter than that of a conventional injection nozzle. Therefore, depending on the height of the evaporation chamber 11, the droplets may not be completely evaporated and the unevaporated fuel cost in the lower part may reach part 16; Since it is lower than the connection port of the heated air introduction pipe 12 and the wall surface temperature is not too high, it does not evaporate and is returned to the oil level regulator 23 through the recovery pipe 14 and reused.

In addition, when using a conventional injection nozzle, the spray spreads at a certain angle and tends to collide with the side of the evaporation chamber, whereas in the present invention, the droplets drop directly downward from the hollow needle 22 due to gravity. Therefore, the possibility of droplets colliding with the sides of the evaporation chamber is reduced, and the disadvantage of vapor condensation on the sides is reduced. This also increases the degree of freedom in the layout of each member.

The cylindrical container 10 may have a cylindrical shape, a square cross section, or a rectangular cross section. However, when a cylindrical container 10 is used as in this embodiment, a shape as shown in FIG. 3 is used. (By introducing the heated air tangentially into the cylindrical container 10, the cylindrical container 10 and the whole can be downsized.

FIGS. 4(A) and 4(B) are an overall configuration diagram and a plan view of another implementation device of the present invention. This implementation device shows an example of the layout of each part when a cylindrical container 10 with a rectangular cross section is used. By arranging each part as shown in the figure, the cylindrical container IO and the entire container can be downsized. The functions and effects of the device are similar to those of the previously described embodiments. The same reference numerals are given to members having the same functions, and the description thereof will be omitted.

<Effects> The present invention has the above configuration, and according to the liquid fuel combustion apparatus according to claim 1, a liquid fuel dripping means for finely dropping liquid fuel is provided in the upper part of the evaporation chamber, and the liquid fuel is dripped from the means. Since the liquid fuel that is dripped is directly evaporated by the rising airflow of heated air, the liquid fuel can be directly evaporated and vaporized at a relatively low temperature. Therefore, there is less tar, etc., and energy is saved. Furthermore, by using a liquid fuel dripping means instead of using an injection nozzle, it is possible to supply liquid fuel with less fuel clogging and a large aperture ratio. Furthermore, condensation of evaporated fuel on the wall surface of the evaporation chamber is reduced, and the degree of freedom in layout of various parts of the apparatus is increased.

[Brief explanation of the drawing]

Fig. 1 is an overall configuration diagram of an apparatus for implementing the present invention, Fig. 2 is a partial detailed view of the apparatus for implementing the invention, Fig. 3 is a plan view of the apparatus for implementing the invention, and Fig. 4 (
A) and (B) show other embodiments, (A) is an overall configuration diagram, (B) is a plan view, and FIGS. 5 (A) and (B) are conventional examples, and (A) is an overall The configuration diagram, (B) is a cross-sectional view taken along line DD in the diagram (A). 11: Evaporation chamber 12: 14: 15: 21: 22: 25: Heated air introduction pipe Combustion section Heater oil tank Hollow needle oil supply pipe

Claims (1)

[Claims] (1) A liquid fuel combustion device in which granulated liquid fuel is directly catalytically evaporated with heated air in an evaporation chamber, and the resulting mixture is sent to a combustion section for combustion,
A liquid fuel dripping means is provided in the upper part of the evaporation chamber to drop the liquid fuel into fine particles, and the liquid fuel dripping from the means is directly evaporated by an upward current of heated air. liquid fuel combustion equipment.