JPH0220570Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field The present invention is based on a fluidized bed combustion furnace, in which a fluidized material is filled on a grid plate suspended at the bottom of a fluidized bed combustion furnace, a reaction tube is inserted into the fluidized material, and a reaction tube is inserted into the fluidized bed combustion furnace. A pipe burner type in which a burner main body connected to a fuel supply equipment and a blower is inserted into the fluidized bed combustion furnace by penetrating a side wall intermediate between the grid plate and the lower end of the reaction tube of the combustion furnace. This invention relates to improvements in heating burners for fluidized beds.

BACKGROUND ART FIG. 4 shows a conceptual diagram of a conventional heating burner for a fluidized bed. In this fluidized bed heating burner, a certain amount of particles with a certain particle size (referred to as fluidized material 12) is charged and stored in a vertical column-shaped fluidized bed combustion furnace 11, and a medium to be heated flows in this fluidized material 12. A reaction tube 13 is inserted and mounted. Then, combustion air and fuel are sent from the blower 14 and the fuel supply equipment 15 to the burner 16a installed in the exhaust gas generating furnace 16, and after combustion, the exhaust gas is transferred to the plenum chamber 1.
It is now being sent to 7th. On the other hand, blower 1
The air passing through the blast pipe 19 from 4 is sent to the plenum chamber 17 where the temperature is adjusted to below the heat resistance level, and is ejected through the grid plate 18 into the fluidized bed combustion furnace 11 to fluidize the fluidized material 12 and fuel. It is designed to heat the fuel above the ignition temperature.

When the fluidized material 12 is stored in this way, when gas is ventilated from below the grid plate 18 and its flow rate is increased, the flow velocity between the particles gradually increases, the particles are blown up, and the air flow between the particles increases. The space becomes larger and the particles that were blown up will fall back down.

Furthermore, when the aeration rate is increased, the vertical movement of the particles becomes more intense, producing a large number of bubbles, and around the bubbles a fluidized bed is formed in which the particles flow down to fill the traces of the bubbles.

This fluidized bed has a uniform internal temperature and a high heat transfer coefficient, so by inserting reaction tubes 13 such as various heat exchangers into this fluidized bed, there is no local thermal damage and uniform heating is achieved. Moreover, it is effective for good heat transfer.

Problems to be solved by the invention However, since the grid plate 18 is exposed to high temperatures and the total weight of the fluidized material 12 is heavy, the grid plate 18 is not heat resistant.
A material with excellent strength is required, or depending on the allowable conditions of the grid plate 18, it is necessary to lower the exhaust gas temperature considerably (around 700 to 800°C), which limits the heating temperature of the reaction tube 13 and reduces thermal efficiency. improvement is hindered.

The present invention was devised in view of the problems of the prior art, and aims to provide a novel heating burner for a fluidized bed that achieves stable combustion at high temperatures.

Means for Solving the Problems In order to achieve this objective, in the fluidized bed heating burner of the present invention, a fluidized material is filled on a grid plate that spans the lower part of the fluidized bed combustion furnace, and the fluidized material is A reaction tube is inserted into the fluidized bed combustion furnace, and the burner body, which is connected to a fuel supply equipment and a blower, is inserted into the interior of the fluidized bed combustion furnace by passing through a side wall intermediate between the grid plate and the lower end of the reaction tube. In a pipe burner-type heating burner for fluidized bed, the burner body is composed of an air supply pipe and a fuel supply pipe that overlaps with the axes aligned within the air supply pipe, and both supply pipes are connected to each other. Bend the proximal end side to the horizontal part and the distal end side to the vertical part, and
The vertical part is arranged upward so that it is located below the reaction tube in the fluidized bed combustion furnace, and a blind plate is provided at the upper end of the vertical part to close off both supply pipes, and a blind plate is provided below the blind plate. , an air nozzle communicating with the air supply pipe and a fuel nozzle inserted in the center of the air nozzle and communicating with the fuel supply pipe are arranged in plural sets in the circumferential direction and directed diagonally downward. It is characterized by having been.

Embodiments The present invention will now be described in detail with reference to illustrative embodiments. Note that the same reference numerals are used for components common to the conventional one.

In FIG. 1, 21 is a burner main body, which is inserted between the lattice plate 18 that spans the lower part of the fluidized bed combustion furnace 11 and the lower end of the reaction tube 13 that is inserted into the fluidized material 12 from above. It is connected to supply equipment 15 and blower 14 . The burner body 21 is composed of a horizontal portion 21a and a vertical portion 21b, and the vertical portion 21b is disposed upward so that its axis substantially coincides with the reaction tube 13. Their axes also coincide with the axes of the fluidized bed combustion furnace 11.

The burner body 21, as shown in FIG.
It is composed of a large-diameter air supply pipe 31 and a small-diameter fuel supply pipe 32 that overlaps within the air supply pipe 31 with their axes aligned, and each of these supply pipes 31 and 32 has a horizontal part 31a, 32a and a vertical part. It is bent into 31b and 32b. That is, the horizontal part 21a of the burner main body 21 consists of an air supply pipe horizontal part 31a and a fuel supply pipe horizontal part 32a, which are overlapped with their axes substantially aligned, and the vertical part 21b of the burner main body 21 is arranged with their axes substantially aligned. It consists of an air supply pipe vertical section 31b and a fuel supply pipe vertical section 32b which are substantially aligned and overlapped.

The upper end of the vertical portion 21b of the burner body 21 is covered with a blind plate 21c. That is, both the supply pipes 3
The upper ends of the vertical portions 31b and 32b of Nos. 1 and 32 are simultaneously closed off by blind plates 21c.

Below the blind plate 21c, there is an air nozzle 3a communicating with the air supply pipe 31, and a fuel supply pipe 3 inserted into the center of the air nozzle 3a.
2 and a fuel nozzle 3b communicating with the fuel nozzle 2 are provided so as to form a set and face obliquely downward.

For example, in FIG. 3, three sets of the air nozzle 3a and the fuel nozzle 3b are arranged with a phase difference of 120 degrees in the circumferential direction. However, the number of sets can be arbitrarily selected and arranged at a predetermined phase angle corresponding to the number.

Function Next, the function of the fluidized bed heating burner configured as described above will be explained.

In FIG. 1, when fuel and air are supplied from the fuel supply equipment 15 and the blower 14 to the burner body 21, as shown in FIG. They are dispersed and ejected from the air nozzles 3a through the supply pipe 31 at high speed and mixed in the fluidized bed combustion furnace 11.

In this case, the exhaust gas from the exhaust gas generating furnace 16 is sent to the plenum chamber 17 in advance, and the inside of the fluidized bed combustion furnace 11 is heated above the ignition temperature of the fuel (after this heating, the plenum chamber 17
), the supply of exhaust gas to the burner body 2 is stopped.
When air and fuel are injected into the combustion furnace 11 from each air nozzle 3a and fuel nozzle 3b, ignition combustion starts immediately.

In the combustion furnace 11, the fluidized bed 12 functions as a stabilizer (flame stabilizer) to achieve stable combustion and fluidization. Thereafter, the amounts of air and fuel supplied to the burner body 21 are adjusted to maintain stable combustion and increase the temperature of the fluidized bed.

At this time, the lattice plate 18 below the burner body 21
Since the plenum chamber 17 is mainly supplied with low-temperature air from the blower 14, it is not heated much, so the temperature of the fluidized material 12 can be increased to a considerably high temperature.

Further, relatively low temperature fuel and combustion air are supplied to the burner body 21, and the burner body 21 is supplied with relatively low temperature fuel and combustion air.
1 itself can be cooled, and therefore no special heat-resistant structure is required. Then, the increased sensible heat of the fuel and combustion air is again input into the fluidized bed combustion furnace 11, so there is no heat loss.

On the other hand, by changing the combustion conditions such as the combustion amount of the burner and the air-fuel ratio, it is easy to finely adjust the conditions such as the temperature inside the fluidized bed combustion furnace and the superficial velocity.

Furthermore, if the internal temperature of the fluidized bed combustion furnace is above the ignition temperature, it is always possible to start and stop, and to perform DSS (Daily Late Night Shutdown) operation.

Effects of the Invention As described above, in the fluidized bed heating burner of the present invention, a fluidized material is filled on a grid plate that spans the lower part of a fluidized bed combustion furnace, a reaction tube is inserted into the fluidized material, and a reaction tube is inserted into the fluidized material. A pipe formed by inserting a burner main body into the fluidized bed combustion furnace, which is connected to a fuel supply equipment and a blower by penetrating the intermediate side wall between the grid plate and the lower end of the reaction tube of the fluidized bed combustion furnace. In a burner-type fluidized bed heating burner, the burner body is composed of an air supply pipe and a fuel supply pipe that overlaps with the axes aligned within the air supply pipe, and the base ends of both supply pipes are arranged in a horizontal section. The tip side of the tube is bent into a vertical part, and the vertical part is arranged upward so that it is located below the reaction tube in the fluidized bed combustion furnace, and both supply pipes are closed and shielded at the upper end of the vertical part. A blind plate is provided below the blind plate, and a plurality of air nozzles communicating with the air supply pipe and a plurality of fuel nozzles inserted into the center of the air nozzle and communicating with the fuel supply pipe are disposed below the blind plate. Because they were arranged in pairs and oriented diagonally downward,
The lattice plate is not exposed to high temperatures, so there is no need to select a special one with excellent heat resistance and strength.
Thermal efficiency can be improved by significantly increasing the heating temperature of reaction tubes such as various heat exchangers installed in a fluidized bed combustion furnace, and furthermore, the fuel nozzle and combustion air nozzle are tilted downward. By doing so, the fluidized material that is fluidized and falls can be quickly slid down, and the fluidized material can be prevented from jumping into each nozzle.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of the fluidized bed heating burner of the present invention, Fig. 2 is a vertical sectional view of the main part of the same fluidized bed heating burner, Fig. 3 is a sectional view taken along the - line in Fig. 2, and Fig. 4 is a FIG. 1 is a schematic diagram of a conventional fluidized bed heating burner. 11... Fluidized bed combustion furnace, 12... Fluidized material, 13
... Reaction tube, 14 ... Blower, 15 ... Fuel supply equipment, 18 ... Grid plate, 21 ... Burner body, 3
1...Air supply pipe, 32...Fuel supply pipe, 21
a, 31a, 32a...horizontal part, 21b, 31
b, 32b...vertical part, 21c...blind plate, 3a...
...Air nozzle, 3b...Fuel nozzle.

Claims (1)

[Scope of utility model registration request] A fluidized material is filled on a lattice plate that spans the lower part of the fluidized bed combustion furnace, a reaction tube is inserted into the fluidized material, and a side wall is formed between the lattice plate and the lower end of the reaction tube of the fluidized bed combustion furnace. In a pipe burner-type heating burner for a fluidized bed, in which a burner body is inserted into the fluidized bed combustion furnace and is connected to a fuel supply equipment and a blower through a pipe, the burner body is connected to an air supply pipe. It consists of an air supply pipe and a fuel supply pipe that overlaps with their axes aligned, and the proximal ends of both supply pipes are horizontal and the distal ends are bent into a vertical part, and the vertical part is the fluidized bed combustion It is disposed upward so as to be located below the reaction tube in the furnace, and a blind plate is provided at the upper end of the vertical part to close off both supply pipes, and a blind plate is provided below the blind plate to communicate with the air supply pipe. A fluid flow system characterized in that an air nozzle and a fuel nozzle inserted in the center of the air nozzle and communicating with the fuel supply pipe are arranged in plural sets in the circumferential direction so as to face diagonally downward. Floor heating burner.