JPH085014A - Powder combustion burner - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a powder combustion burner capable of stable combustion without blocking the tip of the burner even with powder particles having a low melting point such as waste plastic particles. [Composition] A powder combustion burner which carries powder particles in a gas phase and ejects and burns them into a furnace 11. A heavy oil jet pipe 2 for spraying a liquid fuel c, and primary air around the heavy oil jet pipe 2 are provided. A secondary air flow of a heavy oil combustion burner having a primary air supply pipe 3 forming a flow passage of a and a secondary air supply pipe 4 forming a flow passage 5 of secondary air b on the outer periphery of the primary air supply pipe 3. In the street,
A plurality of powdery or granular material ejection pipes 6 for carrying the powdery or granular material in a vapor phase and ejecting it into the furnace 11 are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a powder combustion burner, and more particularly to a powder combustion burner for combusting low melting point powder particles represented by plastic powder particles obtained by crushing waste plastic.

[0002]

2. Description of the Related Art In recent years, the amount of waste plastic discarded as industrial waste or general waste has been increasing year by year with the development and diversification of industry. Examples of methods for treating such waste plastics include material recycling, thermal recycling, simple incineration, and landfill, but simple incineration and landfill are merely for the purpose of treating the waste plastics. It has not been used. On the other hand, it is most preferable if the material can be recycled, but it is difficult to put it into practical use because there are many obstacles to recycling waste plastics mixed with various kinds of plastics to commercialize the waste plastics, and moreover, the cost is increased.

Therefore, as the most practical and effective treatment method, various thermal recycling methods have been proposed in which waste plastic is burned as fuel and the amount of heat thereof is recovered. Originally, plastics, which are mainly made of petroleum, have combustion characteristics superior to those of coal, and even waste plastics have high commercial value from the viewpoint of fuel. One of the thermal recycling methods for waste plastics is, for example, a method in which waste plastics are crushed into finely crushed particles, which are conveyed in a gas phase, burned in a burner, and recovered in a boiler.

By the way, the waste plastic powder and granules are low-melting substances that melt at, for example, 200 to 300 ° C., and if such low-melting powder granules are to be burned using a conventional heavy oil burner or slurry burner. While the powder or granules are heated to a temperature higher than the melting point and melted by flames or radiant heat from burner tiles, the burner tip is blocked, or a large lump or flaky melt is dropped from the burner tip. However, the problem of incomplete combustion occurs due to insufficient surface area while floating in the furnace.

Therefore, there is a demand for the development of a powder combustion burner for stably burning low melting point powder particles.

[0006]

SUMMARY OF THE INVENTION In view of the above demands, an object of the present invention is to stabilize a long-term powder particle without blocking the burner tip even if the powder particle has a low melting point, such as waste plastic powder. It is to provide a powder combustion burner capable of burning.

[0007]

In order to achieve the above object, the inventor of the present invention thought that it is most desirable to combust powders using an existing heavy oil cooking boiler device, and as a result of earnest research, a heavy oil burner was found. In the secondary air flow path of, by providing a powder nozzle that carries the powder particles in a gas phase and ejects them into the furnace,
The present invention has been accomplished by finding that powder particles can be transported and jetted into a furnace without melting by utilizing the cooling effect of the secondary air.

That is, the invention claimed in this application is as follows:
It is as follows. (1) A powder combustion burner that conveys powdery particles in a gas phase and injects and burns them into a furnace, wherein a heavy oil ejection pipe for spraying liquid fuel and a primary air flow passage are provided around the outer periphery of the heavy oil ejection pipe. In the secondary air flow passage of a heavy oil combustion burner having a primary air supply pipe to be formed and a secondary air supply pipe forming a secondary air flow passage on the outer periphery of the primary air supply pipe, the powdery particles are vaporized. A powder combustion burner, characterized in that a plurality of powder and granular material ejection pipes for carrying phases and ejecting them into a furnace are provided at equal intervals.

[0009]

[Function] By arranging a plurality of powdery particles ejecting pipes that carry the powdery particles in the vapor phase and eject them into the furnace in the secondary air flow path of the heavy oil burner, strong radiation heat from the flame or burner tile It is easy to melt, for example, even if it is a low melting point granular material crushed from waste plastic, it can be conveyed while being cooled to a melting temperature or lower by the secondary air flowing through the secondary air channel and injected into the furnace. Therefore, it is possible to prevent the powder or granular material from being melted in the powder or granular material ejection pipe before being ejected. Therefore, it is possible to prevent trouble such as blockage of the ejection pipe due to melting of the powder and granules and incomplete combustion due to agglomeration, and the powder and granules can be stably burned for a long period of time.

In the present invention, it is preferable that the ejection port of the powder and granular material ejection pipe is opened slightly inward of the ejection port of the heavy oil ejection pipe, that is, upstream. As a result, it is possible to prevent the tip portion of the powder or granules from being heated by the radiant heat and effectively prevent the powder or granules from being melted before being ejected. In the present invention, it is preferable that the inner peripheral surface of the ejection port of the powder or granular material ejection pipe is coated with ceramic, or the ejection port has an arc-shaped cross section. As a result, the effect of preventing blockage of the powder or granules at the ejection port is improved. Further, it is also possible to make the powder and granular material ejection pipe into a double pipe and cool it with a cooling fluid such as water. Although the number of the powder and granular material ejection pipes is not particularly limited, it is preferably an even number such as 6 or 8, and it is preferable to dispose the powder and granular material ejection pipes at equal intervals on the entire circumference of the secondary air flow path.

[0011]

EXAMPLES Next, the present invention will be described in more detail by way of examples. FIG. 1 is a longitudinal sectional view showing an embodiment of the powder combustion burner according to the present invention, and FIG. 2 is a view as seen from the direction A in FIG.
In the figure, this powder combustion burner includes a heavy oil ejection pipe 2 having a heavy oil ejection port 1, a primary air supply pipe 3 forming a flow path of primary air a on the outer periphery of the heavy oil ejection pipe 2, and the primary air supply. The swirler 8 provided at the tip of the pipe 3, the secondary air supply pipe 4 forming a flow path of the secondary air b on the outer circumference of the primary air supply pipe 3, and the secondary air supply pipe 4 In the secondary air flow path 5, the eight powdery or granular material ejection pipes 6 arranged at equal intervals in the circumferential direction and the powdery or granular material ejection port 7 at the tip of the powdery or granular material ejection pipe 6 are provided. It is mainly composed. Reference numeral 9 is an ignition burner, 10 is a sight glass, 11 is a furnace, and 14 is a burner tile.

In such a configuration, the primary air supply pipe 3 and the secondary air supply pipe 4 are respectively supplied with a predetermined amount of primary air a and secondary air b, and in this state, a predetermined amount of liquid fuel c, for example, C heavy oil is injected from the jet port 1 into the furnace 11 through the heavy oil jet pipe 2, mixed with the primary air a and the secondary air b forming a swirling flow in the swirler 8, and ignited by the ignition burner 9 and burned. To do. After the combustion of the liquid fuel c ignited in this way becomes stable, a waste-plastic mixture obtained by pulverizing waste plastics such as polyethylene, polypropylene, polystyrene, etc., for example, to a size of 1000 μm or less and air and a solid-air mixture are mixed. d is
The secondary air b flowing through the secondary air flow path 5 through the powder and granular material ejection pipe 6 flows while being cooled to a melting temperature or lower, for example, 200 to 300 ° C. or lower, and flows from the powder or granular material ejection port 7 into the furnace 11. It is injected and burned.

According to the present embodiment, the heavy oil burner is improved so that the granular material is burned, so that the existing boiler device can be effectively used to remove the granular material having a low melting point such as waste plastic. Since it can be combusted, it is possible to deal with the technology for converting waste plastic into powder fuel without requiring any special capital investment. According to the present embodiment, by providing the plurality of powder and granular material ejection pipes 6 in the secondary air flow path 5 of the heavy oil burner, the gas-solid mixture d in which the waste plastic powder and granular material is mixed with the air is produced. Since the waste plastic powder can be conveyed while being kept at a temperature equal to or lower than the melting point of the waste plastic and ejected from the ejection port 7 to the furnace 11, the powder ejection pipe 6 and the powder ejection port 7 of the waste plastic are melted. It is possible to prevent clogging and stably burn the waste plastic particles.

In the present embodiment, it is preferable to reduce the supply amount of the liquid fuel c by a predetermined amount after the combustion of the powdery or granular material is stabilized.

[0015]

EFFECTS OF THE INVENTION According to the present invention, by arranging a plurality of powder and granular material ejection pipes in the secondary air flow path of a heavy oil burner, even a powder and granular material having a low melting point can be vaporized without melting. Since the particles can be phase-conveyed and injected into the furnace, it is possible to prevent the powder and granular material ejection pipe and the ejection port from being blocked, and to stably and completely combust the powder and granular material.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a powder combustion burner which is an embodiment of the present invention.

FIG. 2 is a view from the direction A in FIG.

[Explanation of symbols]

1: Heavy oil ejection port, 2: Heavy oil ejection pipe, 3: Primary air supply pipe, 4: Secondary air supply pipe, 5: Secondary air flow path, 6: Powder particle ejection pipe, 7: Particle ejection port , 8: swirler, 9: ignition burner, 10: sight glass, 11: furnace.

Front Page Continuation (72) Inventor Masaaki Nonaka 3-1-1 Tam, Tamano-shi, Okayama Mitsui Engineering & Ships Co., Ltd. Tamano Works Co., Ltd. (72) Inventor Yoshihiro Kodama 3-1-1 Tamama-shi, Tamano-shi, Okayama Company Tamano Works (72) Inventor Masanori Shirakawa 3-1-1 Tam, Tamano City, Okayama Prefecture Mitsui Engineering & Shipbuilding Co., Ltd. Tamano Works

Claims (1)

[Claims] 1. A powder combustion burner which carries powder particles in a gas phase and jets and burns them into a furnace, wherein a heavy oil jet pipe for spraying liquid fuel and a primary air flow around the outer periphery of the heavy oil jet pipe. In the secondary air flow passage of a heavy oil combustion burner having a primary air supply pipe forming a passage, and a secondary air supply pipe forming a secondary air passage on the outer periphery of the primary air supply pipe, a granular material A powder combustion burner, characterized in that a plurality of powder and granular material ejection pipes for carrying the material in a gas phase and ejecting it into a furnace are provided at equal intervals.