JPS602409Y2 - Pulverized coal combustion burner - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a pulverized coal combustion burner for ejecting strongly caking coal into a furnace for stable combustion.

The structure and shape of a conventional pulverized coal combustion burner will be explained in detail with reference to FIGS.

In Figure 1, 01 is the air compartment, 02 is the coal compartment, 03 is the fuel pipe, and 04
05 is an air nozzle, 05 is a coal nozzle, 06 is a coal packet, and 07 is a connection portion between the fuel pipe and the coal packet.

08 is a pulverized coal-air mixture passage, 09 is a coal nozzle air passage, and 010 is a coal packet mixture passage.

The mixture of pulverized coal and air passes through the fuel pipe 03, passes through the connection part 07 of the recall packet 06, and then enters the coal nozzle 05.
It is ejected from call packet 06 of .

On the other hand, the high temperature secondary air passes through the air compartment 01 and the coal compartment 02, and then passes through the air nozzle 04,
It is ejected into the furnace from around the coal bucket 06 of the coal nozzle 05.

Immediately after the pulverized coal is ejected from the coal packet 06, it is ignited and burned by the radiant heat in the furnace.

At this time, each of the air nozzles 04 and coal nozzles 05 receives radiant heat from inside the furnace and reaches a considerably high temperature.

The mixture of pulverized coal and air passes through fuel pipe 03,
Connection part 0 between fuel pipe 03 and call packet 06
7, it is supplied to the coal packet 06, and is ejected into the furnace through the coal packet passage 010.

On the other hand, high-temperature secondary air is supplied into the furnace through the air passage of the coal compartment 02 and through the coal nozzle air passage 09.

In a coal burner having such a configuration and operation, the temperature of the coal packet 06 becomes considerably high due to the radiant heat within the furnace and the high temperature secondary air flowing through the coal nozzle air passage 09.

Therefore, coal that has strong caking and adhesion properties becomes caking properties (the property of adhering to sticky objects) as the temperature of the coal particles increases, so the radiant heat inside the furnace reaches a high temperature state. Coal particles adhere to the surface of the coal packet 06.

When a tilt mechanism is adopted for the connecting portion between the fuel pipe 03 and the coal packet 06, coal particles are particularly likely to adhere thereto because vortices are likely to occur in the flow of the air-fuel mixture due to the structure.

Once the coal particles begin to adhere, the pulverized coal that flows continuously inside the coal packet 06 adheres to the surface of the connecting part 07 between the fuel pipe 03 and the coal packet 06, gradually grows and accumulates, and finally ends up in the flow path of the coal packet 06. This has the drawback of clogging the air, leading to unstable combustion and misfires.

Therefore, the present invention was made with the purpose of providing a coal burner in which pulverized coal does not adhere to the connection between the fuel pipe and the coal packet and the surface of the coal packet, and does not cause blockage, in order to stably burn highly cohesive coal.
The present invention is characterized by providing a means for injecting cold air to the joint between the fuel pipe and the coal packet, which removes the vortex generated at the joint and cools the wall of the coal packet, thereby preventing the adhesion of pulverized coal. This prevents deposition.

Hereinafter, one embodiment of the present invention shown in FIGS. 3 and 4 will be specifically described.

In FIG. 3, 2 is a coal compartment, 3 is a fuel pipe, 5 is a coal nozzle, 6 is a coal packet, 7 is a connection part between the fuel pipe and the coal packet,
8 is a pulverized coal and air mixture passage, 9 is a coal nozzle air passage, 10 is a coal packet mixture passage, 11 is a place where a mixture vortex is generated, 12 is a cold air jet nozzle, and 13 is a cold air passage.

In this burner, the mixture of pulverized coal and air in the coal packet 6 and the flow of air in the coal compartment 2 are the same as in the conventional burner, and a description thereof will be omitted.

The difference between the coal packet 6 of this burner and conventional burners is that the connection part 7 between the fuel pipe 3 and the coal packet 6
A cold air jetting nozzle 12 is provided on the upstream side of the cooling air jetting nozzle 12, and the cold air jetted from the cold air jetting nozzle 12° is used to remove the vortex at the air-fuel mixture vortex generation location 11 and to cool the coal packet 6. .

The cold air passes through the cold air passage 13 and passes through the cold air jet nozzle 12.
A portion of the air-fuel mixture vortex is generated from the gap between the connection part 7 between the fuel pipe 3 and the coal packet 26 at the location 11.
, and is supplied to the call packet mixture passage 10 of the call packet 6 .

A portion of the cold air is also supplied to the coal nozzle air passage 9.

The present burner having such a structure and function has the following advantages.

The vortex of the mixture is blown away by ejecting a cold air jet to the mixture vortex generation location 11, and the pulverized coal that tends to adhere to the peripheral wall of the connection part 7 between the fuel pipe 3 and the coal packet 6 is returned to the main flow of the mixture. Since the call packet 6 flows without adhering to the peripheral wall of the call packet 6.

Since the cold air W flows through the call packet 6 in a sandwiched state, the cooling effect of the wall of the call packet is enhanced.

Since the cold air jet mainly acts on the connecting portion 7 between the fuel pipe 3 and the coal packet 6, it does not affect the air-fuel mixture injected into the furnace, and combustion is stable.

It is also advantageous in terms of NOx generation.

Although the present invention has been specifically explained based on one embodiment, the present invention is not limited to this embodiment.

[Brief explanation of the drawing]

Fig. 1 is a side sectional view of a conventional pulverized coal combustion burner, Fig. 2 is a front view of Fig. 1, Fig. 3 is a side sectional view of an embodiment of the present invention, and Fig. 4 is a front view of Fig. 3. It is a diagram. 01...Air compartment, 02,2...
...Call compartment, 03,3...
・Fuel compartment, 04...Air nozzle, 05.5...Coal nozzle, 06,6
......Call packet, 07,7...Connection, 08,8...Mixture passage, 09,9...
... Coal nozzle air passage, 010.10...
... Coal packet mixture passage, 11 ... Mixture vortex generation location, 12 ... Cold air jet nozzle,
13...Cold air passage.

Claims (1)

[Scope of utility model registration request] In a coal burner that is composed of a coal packet that spouts a mixture of pulverized coal and primary air through a fuel pipe, and an air nozzle that spouts only secondary air, cold air is sent to the joint between the fuel pipe and the coal packet. A pulverized coal combustion burner characterized by being equipped with a means for ejecting pulverized coal.