JP2654885B2 - Liquid feeder for fluidized bed - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for supplying a liquid to a fluidized bed, and more particularly to a fluidized bed incinerator or a fluidized bed boiler for burning a waste oil or a waste liquid into a fluidized bed, or a fluidized bed hydrothermal system for coal. The present invention relates to a liquid supply device for injecting water into a gasification reactor, injecting water when a fluidized bed temperature rises in fluidized bed incineration of waste, cooling, and the like.

[0002]

2. Description of the Related Art Conventionally, this type of apparatus has been provided on the bottom, side walls, ceiling, etc. of a fluidized bed combustion apparatus. Generally, a tube is inserted directly into the fluidized bed from the bottom or the side wall, and liquid is injected from the tube. However, since the flowing air tends to flow to the upper center side of the fluidized bed, the bottom and side walls of the fluidized bed have slow flow, and when a large amount of liquid is injected into it, the injection site is wet and fixed by the injected liquid. If the mass of the fluidized medium is moved to a portion where the fluidity is strong as it is, the moisture or oil contained therein may evaporate at once and cause a steam explosion or a deflagration phenomenon. However, even if the tube is inserted deeply into the fluidized bed, for example, in a fluidized bed incinerator or the like, the fluidized bed temperature is usually as high as about 650 to 750 ° C, and the fluidized medium in the fluidized bed is exposed to strong movement. Further, in some municipal solid waste incinerators and the like, salts are accumulated in the fluidized medium by the incineration operation, and some of them show strong erosion corrosion. For this reason, deformation such as bending and corrosive wear were severe, and there was a case where the insertion tube did not have one month.

[0003] From these, for example, a method may be adopted in which a tube is inserted from a side wall at a position higher than the surface of the fluidized bed and liquid is supplied from the tube. In this case, the injected water or oil evaporates immediately on the surface of the fluidized bed that has fallen, forming an air stream containing oil droplets or water droplets, rising along the side wall, and adhering fluid sand and dust to the side wall surface. Let me do it. This becomes more remarkable as the injection amount increases, and in some cases, a layer of several tens of cm adheres to the peripheral side wall even at one week at an injection amount of several hundred liters / hr. In order to avoid this, there is an example in which the liquid is dripped from the position immediately above the center of the fluidized bed. This is less of a problem if wastewater or water is injected into the fluidized bed.However, when trying to inject waste oil etc., a considerable amount evaporates before it reaches the fluidized bed. Therefore, even if an attempt was made to raise the temperature of the fluidized bed by, for example, injecting waste oil, the amount of heat input was small because the oil burned above the fluidized bed. For these reasons, in practice, the above-mentioned simple nozzle method is limited to an extremely small amount of liquid to be injected.

[0004] For injection of a large amount, that is, several tens of liters / hr or more, the pipe is not inserted into the fluidized bed, but is arranged so that the nozzle tip can be seen through a hole provided in the side wall, and the fluid flows from around the nozzle. Many types always blow air for use. FIG. 4 shows a schematic sectional view of this type. In FIG. 4, 1 is a combustion furnace, 2 is a fluidized bed, 3 is a furnace wall, and
An outer tube 4 and an inner tube 5 are provided on the side wall of the air conditioner, and flow air 7 and liquid 8 are supplied to the outer tube 4 and the inner tube 5, respectively.

According to this, although the above-mentioned problems are not present, there are the following disadvantages. The level inserted into the fluidized bed is fixed. Therefore, in the case of oil, the combustion rate in the fluidized bed is determined.
When inserted at a deep position, almost all of the fuel is burned in the fluidized bed and heat is completely input, so that an attempt to raise the furnace top temperature by oil injection has no effect. Also, when the fluidized bed temperature tends to overheat, oil incineration becomes impossible. On the other hand, if it is at a shallow position, the fuel is almost completely burned by the free board, so that there is not much effect on the temperature rise of the fluidized bed. Danger for maintenance The flowing medium may flow back to the flowing air duct. In such a case, the flow cannot be restarted without stopping the flow. Also, unless the flow is stopped, the hot fluid medium blows out,
The injection nozzle cannot be removed. If a clinker or a lump of wet fluid medium is formed at the tip of the injection nozzle, the flowing air cannot enter from around the injection nozzle, which is exactly the same as the simple nozzle method described above.

The injection of the liquid at the tip of the injection nozzle is rarely performed at all times, and is almost always intermittent. When the injection is stopped, the flowing medium flows back to the injection nozzle. Therefore, there is a possibility that the nozzle is clogged at the time of re-injection. Since the fluid medium usually has an average particle diameter of about 0.5 to 2 mm, the nozzle tip hole diameter is at least 5 m.
m or more, and even in such a case, clogging may occur due to carbon formation or dry scale. No insertion length in fluidized bed No insertion length in fluidized bed, so injection or lubrication is limited to near the injection nozzle mounting hole. As described above, since the flow near the wall is weak, local cooling or local heating occurs, which is not preferable due to reaction or combustion.

[0007]

SUMMARY OF THE INVENTION The present invention overcomes the limitations of the prior art by adjusting the depth of insertion into the fluidized bed and allowing the injection nozzle to be removed even when the fluidized bed is in operation. And high safety by eliminating dangerous situations such as steam explosion, deflagration, and backflow of the fluid medium, and there is no danger of closing the injection nozzle even during intermittent injection. It is an object of the present invention to provide a liquid supply apparatus for a fluidized bed capable of injecting into a portion having a strong flow away from a wall surface and capable of withstanding a large-volume injection exceeding a maximum of 500 liter / hr. is there.

[0008]

According to the present invention, there is provided a liquid supply apparatus for supplying a liquid to a fluidized bed of a fluidized bed combustion apparatus, comprising: An outer pipe having an open end inclined and protruding to the fluidized bed portion, an inner pipe inserted into the outer pipe and having an open end near the open end of the outer pipe, and a double pipe, The inner pipe is connected to the liquid supply means, and the gap between the inner pipe and the outer pipe is connected to the gas supply means, and the outer end of the combustion device of the outer pipe is higher than the highest operating surface level of the fluidized bed. It is what it was.

In the above-mentioned supply device, the gas to be supplied to the gap between the inner pipe and the outer pipe may be such that the original pressure is larger than the pressure of the flowing air at the insertion position and there is no fear of backflow. For example, air supplied by a small blower or compressed air may be used separately. In addition, the tip of the liquid injection nozzle of the inner pipe is slightly shorter than the tip of the protective pipe (outer pipe), and it is more convenient not to directly contact the fluidized bed because heat transfer from the fluidized bed to the injection pipe (inner pipe) is suppressed. Is good. Further, in order to prevent damage to the hearth and the air diffuser nozzle due to the injection fluid or the blown air, it is necessary to keep the injection position at least 100 mm higher than the hearth.

[0010]

Since the injection nozzle is inclined, the outer end of the mounting nozzle is higher than the surface of the fluidized bed, and the outer end of the protective tube, which is the outer tube, is also at a higher position while the injection position is in the fluidized bed. In addition, by extending the insertion length into the fluidized bed, it is possible to change the liquid injection position to a position deeper in the fluidized bed away from the side wall. Also, the injection nozzle is isolated from the fluidized bed by air in the gap with the protective nozzle of the outer tube. Further, if the liquid injection tube and the outer tube have a ground structure, the insertion length can be made variable. The injection nozzle has a structure that can be supported by the protection tube of the outer tube in terms of strength, and the diameter of the injection nozzle can be reduced to reduce the amount of liquid held in the injection nozzle. However, the diameter of the injection nozzle is preferably 5 mm or more from the standpoint of clogging by the flowing medium.

[0011]

EXAMPLES The present invention will be described below in more detail with reference to examples, but the present invention is not limited to these examples. Embodiment 1 FIG. 1 shows a schematic sectional view of a fluidized bed combustion apparatus provided with a liquid supply apparatus of the present invention. In FIG. 1, a combustion furnace 1 having a fluidized bed 2, a free board 10, and an aeration nozzle 11 is provided with a furnace mounting nozzle 12 that penetrates a side wall 3 from the outside of the furnace 1 obliquely downward. . The liquid supply device 6 of the present invention is installed in the furnace nozzle 12. The liquid supply device 6 includes a protective tube (outer tube) 4 and an injection nozzle (inner tube) 5. The protective tube 4 is fixed to a furnace mounting nozzle 12 at an outer end 9, and the outer end 9 is a fluidized bed. Is provided at a position higher than the maximum operating surface level of the vehicle. The injection nozzle (inner pipe) 5 is connected to the liquid supply means above the outer end 9, and the gap between the injection nozzle (inner pipe) 5 and the protective tube (outer pipe) 4 is the outer end. At the top of 9, it is connected to a source of flowing air. This liquid supply device 6
Is inserted deep inside the fluidized bed 2 so that liquid (water or oil) can be injected deep inside the fluidized bed.

FIG. 2 shows another example of the liquid supply device. In FIG. 2, the connection between the furnace mounting nozzle 12 and the protection cylinder 4 is performed by a gland structure including a gland 13 and a gland presser 14, so that the liquid supply device 6 can be slid and inserted into the fluidized bed 2. Is adjustable. FIG. 3 shows a front view of the injection nozzle (inner tube).
In this way, the sparger 16 is attached near the tip of the injection nozzle, and the gap with the protection cylinder can be mechanically held.
Further, it is preferable that the protective cylinder is made of a thick wall, and is made of a heat resistant steel such as SUS, so as to withstand abrasion with strength.

[0013]

According to the present invention, the following effects can be obtained by the above configuration. By changing the insertion length by making such an inclination, the position of the injection nozzle in the fluidized bed in the depth direction can be changed. Even if it is pulled out of the device with only the inner tube or the outer tube,
The outer end of the furnace mounting nozzle is located higher than the fluidized bed surface,
In addition, since the furnace mounting nozzle extends obliquely upward with respect to the side wall, the level up to the fluidized bed surface is stopped without flowing air and is filled with a fluidized medium fixed and layered. Will be retained. Of course, no hot flowing medium will blow out.

[0014] Since it is inserted into the fluidized bed at an angle,
It can be inserted by extending the insertion length far to the center from the wall. Further, since the outside of the injection nozzle is held by an outer tube having a large thickness and a large diameter, vibration and deformation hardly occur. Cooling through the fluidizing air between the doubles prevents the heat of the fluidized bed from being transmitted directly to the inner tube, which is the injection nozzle,
Preventing the formation of evaporative dry scale and carbon on the inner surface of the inner tube also enables this long insertion. For this reason, it is possible to inject the fluid into a location with strong flow away from the wall, and a maximum of 50
A flow rate of more than 0 liter / hr can be injected with a single nozzle without any hindrance, whereby the possibility of steam explosion or deflagration does not occur because there is no formation of wet lumps due to intense movement of the flowing medium.

As described above, the formation of evaporative dry scale and carbon can be prevented, and it is not necessary to atomize at the tip of the injection nozzle due to the dispersing action due to the violent flow. Therefore there is no possibility of clogging. As described above, the problems of the conventional technology can be solved, and a good technology such as ease of use, safety, and reliability can be provided. As a result, the technical convenience, safety, reliability and reliability of liquid combustion in fluidized bed combustion equipment,
It is very effective for improvement of maintenance and so on.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of a fluidized bed combustion furnace provided with a liquid supply device of the present invention.

FIG. 2 is a schematic cross-sectional view of another liquid supply device of the present invention.

FIG. 3 is a front view showing an example of an injection nozzle.

FIG. 4 is a schematic sectional view of a fluidized bed combustion furnace provided with a conventional liquid supply device.

[Explanation of symbols]

1: combustion furnace, 2: fluidized bed, 3: furnace wall, 4: protective tube (outer tube), 5: injection nozzle (inner tube), 6: liquid supply device,
7: Flowing air, 8: Liquid, 9: Outer end, 10: Free board, 11: Aeration nozzle, 12: Furnace nozzle, 13:
Gland, 14: Ground presser, 15: Flexible hose, 16: Spacer

 ──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Yoshinori Sakamoto 1-6-27 Konan, Minato-ku, Tokyo Inside Ebara Environmental Engineering Co., Ltd. (56) References JP-A-59-104006 (JP, A) 46-33326 (JP, A)

Claims (1)

(57) [Claims] 1. A liquid supply device for supplying a liquid to a fluidized bed of a fluidized bed combustion device, comprising: an outer tube having an open end which is inclined downward from the outside of the combustion device to the inside through a side wall, and protrudes to a fluidized bed portion. An inner tube inserted into the outer tube and having an open end near the open end of the outer tube, the inner tube being connected to liquid supply means, Liquid supply to the fluidized bed characterized in that the gap between the outer tube and the outer tube is connected to a gas supply means and the outer end of the combustion device of the outer tube is higher than the highest operating surface level of the fluidized bed.