JP6826365B2 - Powder combustion equipment - Google Patents

Description

The present invention relates to the powder combustion equipment for burning the pulverized combustible materials.

Such a powder combustion device burns fine powdery combustibles, and as an example of powdery combustibles, petroleum coke obtained in the process of petroleum refining (petroleum coke) is made into fine powder. Examples thereof include fine powder, fine pulverized coal obtained by pulverizing coal, organic sludge powder obtained by removing volatile components and water from organic sludge to make fine powder, and waste plastic powder obtained by removing waste plastic into fine powder.

In general, powdery combustibles have lower combustibility (easiness of combustion) than fuels such as gas fuels and liquid fuels, and it is difficult to stably burn powdery combustibles by themselves. A technique for stable combustion of an object using an auxiliary fuel such as gas fuel or liquid fuel has been proposed.

For example, a powder mixed gas ejection part that ejects a powder mixed gas that is a mixture of powdery combustible material, transport air, and gas fuel, and a powder mixed gas ejected from the powder mixed gas ejection portion are burned. An air ejection part for ejecting the air to be generated was provided adjacent to the air ejection portion. Further, as another example, the air ejection portion is provided in an annular shape so as to surround the outer peripheral portion of the powder mixed gas ejection portion over the entire circumference (see, for example, Patent Document 1).
That is, it is contained in the powder mixed gas by mixing the powdery combustible material with the highly combustible gas fuel in addition to the transport air and ejecting it as the powder mixed gas from the powder mixed gas ejection part. The gas fuel is spread and burned throughout the powder mixed gas by the transport air contained in the powder mixed gas and the air ejected from the air ejection part, and the flame is ignited. The powdery combustible material in the powder mixed gas was burned so as to stably burn the powdery combustible material.

Japanese Unexamined Patent Publication No. 2014-122743

However, in the conventional powder combustion apparatus, the gas fuel contained in the powder mixed gas ejected from the powder mixed gas ejection part is powdered at a high combustion speed by the transport air also contained in the powder mixed gas. Since it burns in a state of spreading throughout the mixed gas, the flame ignites and the powdery combustible material in the powder mixed gas burns at a high combustion rate. Therefore, there is a problem that a local high temperature region (so-called hot spot) is likely to occur, and the amount of thermal NOx generated increases accordingly.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a powder combustion apparatus and a powder combustion method capable of reducing NOx.

The powder burning device according to the present invention for achieving the above object is a powder burning device that burns powdery combustibles, and its characteristic configuration is as follows.
A powder-mixed air ejection cylinder that ejects powder-mixed air, which is a mixture of powdery combustibles and air, from the tip opening.
It is provided with a gas fuel ejection cylinder that is arranged inside the powder mixed air ejection cylinder in the radial direction and ejects gas fuel from the gas fuel ejection portion at the tip.
The gas fuel ejection cylinder is arranged in a state in which only the powder mixed air flows through the space between the gas fuel ejection cylinder and the powder mixed air ejection cylinder, and the gas ejected from the gas fuel ejection portion. Only the air contained in the powder mixture air is burned as the fuel for primary combustion,
An air ejection portion for ejecting air for burning powdery combustibles in the powder mixed air ejected from the tip opening is provided on the outer peripheral portion of the tip opening of the powder mixing air ejection cylinder .
The amount of gas fuel burned relative to the total amount of combustion, which is the sum of the amount of combustion of powder mixed air ejected from the tip opening of the powder mixed air ejection cylinder and the amount of combustion of gas fuel ejected from the gas fuel ejection portion. Gas combustion amount ratio adjusting means for adjusting the gas combustion amount ratio, which is the ratio of
Depending on the ease of combustion of the powdery combustible material, the lower the ease of combustion, the larger the gas combustion amount ratio is set, and the gas combustion amount ratio and the type of the powdery combustible material are set. The gas combustion amount ratio adjusting means is controlled so as to have the gas combustion amount ratio corresponding to the type of the powdery combustible material set by the powdery combustible material type setting switch based on the gas combustion amount ratio information indicating the relationship. The point is that it is equipped with control means .

According to the above characteristic configuration, only the powder mixed air flows through the space between the gas fuel ejection cylinder and the powder mixed air ejection cylinder, and the powder mixed air that flows in this way is ejected from the powder mixed air. The gas fuel is ejected from the tip opening of the cylinder, and the gas fuel is ejected from the gas fuel ejection portion toward the inside of the ejection flow of the powder mixed air.
Since the gas fuel ejected from the gas fuel ejection portion is not provided with a dedicated combustion air supply means for supplying combustion air so as to be in direct contact with the gas fuel, the gas fuel is not provided. The gas fuel ejected from the ejection part toward the inside of the ejection flow of the powder mixed air burns only the air contained in the powder mixed air as the primary combustion air, and is a powdery combustible substance in the powder mixed air. Will burn the air in the powder mixed air as the primary combustion air.

That is, primary combustion in powder mixed air for burning powdery combustibles by burning the gas fuel ejected from the gas fuel ejection part by positively utilizing the air in the powder mixed air. Since the density of the working air can be lowered over a wide range of the jet flow of the powder mixed air, the powdery combustibles in the powder mixed air can be slowly burned, and the generation of the local high temperature region can be satisfactorily suppressed. it can.
Therefore, since the generation of thermal NOx can be suppressed, it is possible to provide a powder combustion apparatus capable of reducing NOx.
Further, according to the above-mentioned characteristic configuration, the powdery combustible material in the powder mixed air ejected from the tip opening of the powder mixed air ejection cylinder burns the air in the powder mixed air as the primary combustion air. Further, the air ejected from the air ejection portion is burned as, for example, secondary combustion air.
That is, although a part of the air in the powder mixed air ejected from the tip opening of the powder mixed air ejection cylinder is consumed for combustion of the gas fuel ejected from the gas fuel ejection portion, the powder mixed air Since air is ejected from the air ejection portion on the outer peripheral portion of the tip opening of the ejection cylinder to the outer peripheral portion of the powder mixed air ejected from the tip opening of the powder mixed air ejection cylinder, it is contained in the powder mixed air. It is possible to prevent a shortage of air for combustion of powdery combustibles.
Therefore, it is possible to reduce NOx while completely burning the powdery combustible material.
Further, according to the above-mentioned characteristic configuration, the lower the ease of combustion of the powdery combustible material, the larger the gas combustion amount ratio, so that the ease of combustion of the powdery combustible material is low. The more the gas fuel is supplied, the more the gas fuel can be burned in a wide range of the powder mixed air ejected from the tip opening of the powder mixed air ejection cylinder, so that the combustion flame of the gas fuel can be burned. In the form of igniting, powdery combustibles in powder mixed air can be stably and slowly burned over a wide range regardless of the difference in ease of combustion.
That is, the lower the ease of combustion of the powdery combustible material, the more likely the local high temperature region to occur in the direction of ejection of the powder mixed air, but the gas fuel is sent to the vicinity of the place where the local high temperature region is expected to occur. Therefore, since the air in the powder mixed air can be positively consumed, the generation of a local high temperature region can be effectively suppressed.
Therefore, regardless of the difference in the ease of burning the powdery combustible material, the powdery combustible material can be stably burned, and the NOx can be reduced.

The powder burning device according to the present invention for achieving the above object is a powder burning device that burns powdery combustibles, and its characteristic configuration is as follows.
A powder-mixed air ejection cylinder that ejects powder-mixed air, which is a mixture of powdery combustibles and air, from the tip opening.
It is provided with a gas fuel ejection cylinder that is arranged inside the powder mixed air ejection cylinder in the radial direction and ejects gas fuel from the gas fuel ejection portion at the tip.
The gas fuel ejection cylinder is arranged in a state in which only the powder mixed air flows through the space between the gas fuel ejection cylinder and the powder mixed air ejection cylinder, and the gas ejected from the gas fuel ejection portion. Only the air contained in the powder mixture air is burned as the fuel for primary combustion,
An air ejection portion for ejecting air for burning powdery combustibles in the powder mixed air ejected from the tip opening is provided on the outer peripheral portion of the tip opening of the powder mixing air ejection cylinder.
The amount of gas fuel burned relative to the total amount of combustion of the powder mixed air ejected from the tip opening of the powder mixed air ejection cylinder and the amount of gas fuel ejected from the gas fuel ejected portion. Gas fuel ejection speed adjusting means for adjusting the ejection amount of gas fuel to adjust the gas combustion amount ratio, which is the ratio of gas fuel, and adjusting the ejection speed of gas fuel from the gas fuel ejection portion.
Depending on the ease of combustion of the powdery combustible material, the lower the ease of combustion, the larger the gas combustion amount ratio is set, and the gas combustion amount ratio and the type of the powdery combustible material are set. The gas fuel ejection speed adjusting means is controlled so as to have the gas combustion amount ratio corresponding to the type of the powdery combustible material set by the powdery combustible material type setting switch based on the gas combustion amount ratio information indicating the relationship. The point is that it is equipped with control means.

According to the above characteristic configuration, only the powder mixed air flows through the space between the gas fuel ejection cylinder and the powder mixed air ejection cylinder, and the powder mixed air that flows in this way is ejected from the powder mixed air. The gas fuel is ejected from the tip opening of the cylinder, and the gas fuel is ejected from the gas fuel ejection portion toward the inside of the ejection flow of the powder mixed air.
Since the gas fuel ejected from the gas fuel ejection portion is not provided with a dedicated combustion air supply means for supplying combustion air so as to be in direct contact with the gas fuel, the gas fuel is not provided. The gas fuel ejected from the ejection part toward the inside of the ejection flow of the powder mixed air burns only the air contained in the powder mixed air as the primary combustion air, and is a powdery combustible substance in the powder mixed air. Will burn the air in the powder mixed air as the primary combustion air.
That is, primary combustion in powder mixed air for burning powdery combustibles by burning the gas fuel ejected from the gas fuel ejection part by positively utilizing the air in the powder mixed air. Since the density of the working air can be lowered over a wide range of the jet flow of the powder mixed air, the powdery combustibles in the powder mixed air can be slowly burned, and the generation of the local high temperature region can be satisfactorily suppressed. it can.
Therefore, since the generation of thermal NOx can be suppressed, it is possible to provide a powder combustion apparatus capable of reducing NOx.
Further, according to the above-mentioned characteristic configuration, the powdery combustible material in the powder mixed air ejected from the tip opening of the powder mixed air ejection cylinder burns the air in the powder mixed air as the primary combustion air. Further, the air ejected from the air ejection portion is burned as, for example, secondary combustion air.
That is, although a part of the air in the powder mixed air ejected from the tip opening of the powder mixed air ejection cylinder is consumed for combustion of the gas fuel ejected from the gas fuel ejection portion, the powder mixed air Since air is ejected from the air ejection portion on the outer peripheral portion of the tip opening of the ejection cylinder to the outer peripheral portion of the powder mixed air ejected from the tip opening of the powder mixed air ejection cylinder, it is contained in the powder mixed air. It is possible to prevent a shortage of air for combustion of powdery combustibles.
Therefore, it is possible to reduce NOx while completely burning the powdery combustible material.
Further, according to the above-mentioned characteristic configuration, the lower the ease of combustion of the powdery combustible material, the faster the gas fuel ejection speed from the gas fuel ejection portion is adjusted so that the powdery combustible material is ejected. The lower the ease of combustion, the more gas fuel can be delivered to the powder mixed air ejected from the tip opening of the powder mixed air ejection cylinder to the tip in the ejection direction. In the form of igniting the combustion flame of the above, powdery combustibles in powder mixed air can be stably and slowly burned over a wide range regardless of the difference in ease of combustion.
That is, the lower the ease of combustion of the powdery combustible material, the more likely the local high temperature region to occur in the direction of ejection of the powder mixed air, but the gas fuel is sent to the vicinity of the place where the local high temperature region is expected to occur. Therefore, since the air in the powder mixed air can be positively consumed, the generation of a local high temperature region can be effectively suppressed.
Therefore, regardless of the difference in the ease of burning the powdery combustible material, the powdery combustible material can be stably burned, and the NOx can be reduced.

A further characteristic configuration of the powder combustion apparatus according to the present invention is that the powder mixing air ejection cylinder has a cylindrical shape.
The powder mixing air ejection cylinder is arranged inside the cylindrical air ejection cylinder, and is arranged.
The gas fuel ejection portion is composed of a gas fuel nozzle having a circular outer circumference and a plurality of gas fuel ejection holes on the tip surface in a longitudinal direction of the cylinder from the tip side of the powder mixed air ejection cylinder.
An annular powder-mixed air ejection portion for ejecting powder-mixed air is formed between the gas fuel nozzle and the tip opening edge of the powder-mixed air ejection cylinder.
The point is that the annular air ejection portion is formed between the tip opening edge of the powder mixed air ejection cylinder and the tip opening edge of the air ejection cylinder.

According to the above characteristic configuration, gas fuel is ejected from a plurality of gas fuel ejection holes on the tip surface of the gas fuel nozzle, and an annular powder mixed air ejection portion covers the entire circumference of the gas fuel ejected in this manner. The powder mixed air is ejected from the air, and the air is ejected from the annular air ejection portion over the entire circumference of the outer circumference of the powder mixed air thus ejected.
That is, the gas fuel ejected from the gas fuel nozzle is distributed over as wide a range as possible inside the powder mixed air ejected from the annular powder mixed air ejection portion, and the air in the powder mixed air is used as the gas fuel. Since it can be consumed by combustion, slow combustion of powdery combustibles in powder mixed air can be performed more satisfactorily. In addition, since the air ejected from the annular air ejection portion can be distributed over the entire circumference of the outer peripheral portion of the powder mixed air ejected from the annular powder mixed air ejection portion, the powder mixing can be performed. It is possible to accurately prevent the shortage of air for combustion of the powdery combustible material in the air. Therefore, it is possible to further reduce the NOx while accurately and completely combusting the powdery combustible material.

A further characteristic configuration of the powder combustion apparatus according to the present invention is that the powder mixing air ejection cylinder has a rectangular tubular shape with a rectangular crossing shape.
The powder mixing air ejection cylinder is provided inside a square tubular air ejection cylinder having a rectangular crossing shape.
As the air ejection portion, a secondary air ejection portion that ejects secondary combustion air that burns powdery combustibles in the powder mixed air ejected from the tip opening of the powder mixed air ejection cylinder, and a tertiary air ejection portion. A tertiary air ejection part that ejects combustion air is provided.
The secondary air ejection portion having a rectangular frame shape is formed between the tip opening edge of the powder mixed air ejection cylinder and the tip opening edge of the air ejection cylinder.
The point is that the tertiary air ejection portion is separately provided on one side portion of the secondary air ejection portion and the outer peripheral portion of each side portion facing the one side portion.

According to the above characteristic configuration, the powder mixed air is ejected from the tip opening of the square tubular powder mixed air ejection cylinder, and the powder mixed air is ejected in a rectangular frame shape over the entire circumference of the outer circumference. Secondary combustion air is ejected from the secondary air ejection part of the above, and on the outer peripheral portion of the secondary combustion air ejected in this way, the two side portions facing each other in the rectangular frame-shaped secondary air ejection portion The tertiary combustion air is ejected from the tertiary air ejection portion on the outer peripheral portion.
That is, the secondary combustion air ejected from the rectangular frame-shaped secondary air ejection portion goes over the entire circumference of the outer peripheral portion of the powder mixed air ejected from the tip opening of the powder mixed air ejection cylinder as much as possible. Since it can be spread, the powdery combustible material can be combusted evenly over a wide range of the powder mixed air ejected from the tip opening of the powder mixed air ejection cylinder. Further, for the powder mixed air ejected from the tip opening of the powder mixed air ejection cylinder, the tertiary combustion air is supplied from the two tertiary air ejection portions at the tip of the ejection direction, so that it is powdery. The unburned content of combustibles can be burned accurately.
In short, it is possible to more accurately prevent the shortage of combustion air for powdery combustibles in the powder mixed air.
Therefore, it is possible to further reduce NOx while accurately and completely combusting the powdery combustible material.

Longitudinal side view of the powder combustion apparatus according to the first embodiment Front view of the powder combustion apparatus according to the first embodiment Longitudinal side view of the powder combustion apparatus according to the second embodiment Longitudinal side view of the main part of the powder combustion apparatus according to the second embodiment Front view of the powder combustion apparatus according to the second embodiment Partial cutout plan view of the powder combustion apparatus according to the second embodiment

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[First Embodiment]
First, the first embodiment will be described with reference to FIGS. 1 and 2.
The powder combustion apparatus includes a powder mixed air ejection cylinder 1 that ejects a powder mixed air M that is a former mixture of a powdery combustible material F and an air A from a tip opening 1w, and a powder mixed air ejection cylinder 1 A gas fuel ejection cylinder 10 that is arranged inside in the radial direction and ejects gas fuel G from the gas fuel ejection unit 2 at the tip, a control unit 3 (an example of control means) that controls the operation of this powder combustion device, and the like. It is configured with.
Then, the gas fuel ejection cylinder 10 is arranged in a state in which only the powder mixed air M flows through the space between the gas fuel ejection cylinder 10 and the powder mixed air ejection cylinder 1, and the gas fuel ejection portion 2 is provided. The gas fuel G ejected from the gas fuel G is configured to burn only the air A contained in the powder mixed air M as the primary combustion air A.
Further, an air jet for ejecting air A for burning the powdery combustible material F in the powder mixed air M ejected from the tip opening 1w is ejected to the outer peripheral portion of the tip opening 1w of the powder mixed air ejection cylinder 1. A part 4 is provided.

Incidentally, as the gas fuel G, for example, city gas containing methane as a main component such as 13A is used.

In this first embodiment, the powder mixing air ejection cylinder 1 is cylindrical, and the powder mixing air ejection cylinder 1 is arranged inside the cylindrical air ejection cylinder 6.
The gas fuel ejection portion 2 is a gas having a circular outer circumference and a plurality of gas fuel ejection holes 7h on the distal end surface in a tubular longitudinal direction view (axial direction view) from the tip end side of the powder mixed air ejection cylinder 1. It is composed of a fuel nozzle 7.
Then, an annular powder-mixed air outlet 8 for ejecting the powder-mixed air M between the gas fuel nozzle 7 and the tip opening edge of the powder-mixed air ejection cylinder 1 (an example of a powder-mixed air ejection portion). Is formed, and powdery combustible in the powder mixed air M ejected from the powder mixed air outlet 8 between the tip opening edge of the powder mixed air ejection cylinder 1 and the tip opening edge of the air ejection cylinder 6. An annular secondary air outlet 9 for ejecting the secondary combustion air A for burning the object F is formed, and this secondary air outlet 9 corresponds to the air ejection portion 4.

Hereinafter, each part of the powder combustion apparatus of the first embodiment will be described.
The powder mixing air ejection cylinder 1 and the air ejection cylinder 6 are both in a state where the base ends are closed and the tip openings 1w and 6w are directed in the same direction, and the powder mixing air ejection cylinder 1 is an air ejection cylinder. It is arranged concentrically in 6.
The gas fuel ejection cylinder 10 has a cylindrical shape, and the gas fuel ejection cylinder 10 is inserted from the closed end of the air ejection cylinder 6 and the closed end of the powder mixed air ejecting cylinder 1, and the powder mixed air ejecting cylinder 10 is inserted. A gas fuel nozzle 7 is detachably attached to the tip of the gas fuel ejection cylinder 10 which is arranged concentrically inside the first. The gas fuel nozzle 7 has a funnel shape having a larger diameter toward the tip side, and as shown in FIG. 2, the gas fuel nozzle 7 is provided with a plurality of gas fuel ejection holes 7h arranged in a double circle on the tip surface. .. Although not shown, the gas fuel nozzle 7 is produced by, for example, screwing a female screw portion provided at a base end portion thereof into a male screw portion provided at the tip end of a gas fuel ejection cylinder 10. It is attached to the tip of the ejection cylinder 10.

As shown in FIG. 1, in the air ejection cylinder 6, the powder mixed air ejection cylinder 1, and the gas fuel nozzle 7, the tip opening 1w of the powder mixed air ejection cylinder 1 is a cylinder from the tip opening 6w of the air ejection cylinder 6. The gas fuel nozzle 7 is arranged in a relative positional relationship in which the tip surface of the gas fuel nozzle 7 is slightly retracted in the longitudinal direction (axis direction) and is substantially the same position as the tip opening 6w of the air ejection cylinder 6 in the longitudinal direction of the cylinder.
No other member is provided in the annular space between the gas fuel ejection cylinder 10 and the powder mixed air ejection cylinder 1, and the entire space is the powder through which only the powder mixed air M flows. The mixed air flow path 11 is configured to eject the powder mixed air M passing through the powder mixed air flow path 11 from the powder mixed air outlet 8.
That is, the gas fuel G ejected from the gas fuel nozzle 7 is not provided with a dedicated combustion air A supply means for supplying the combustion air A so as to be in direct contact with the gas fuel G. The source of the combustion air A for the gas fuel G ejected from the gas fuel nozzle 7 is only the powder mixed air M in which the air A is originally mixed and ejected from the powder mixed air ejection port 8.

Further, the annular space between the powder mixing air ejection cylinder 1 and the air ejection cylinder 6 is a secondary air flow path 12 through which the secondary combustion air A flows, and passes through the secondary air flow path 12. The secondary combustion air A to be flowed is ejected from the secondary air outlet 9.
At the tip of the secondary air flow path 12, a swirling vane 13 for swirling the secondary combustion air A ejected from the secondary air injection port 9 is provided.

Further, although not shown, the furnace wall 26 (see FIG. 1) of the heating furnace to which the powder combustion device is attached is provided with a tertiary air outlet for ejecting tertiary combustion air, and the tertiary air outlet is provided. A tertiary air damper is provided to adjust the amount of tertiary combustion air ejected from.

As shown in FIG. 1, the powder mixed air supply cylinder 14 is inserted from the peripheral wall portion of the air ejection cylinder 6 into the portion on the closed end side of the peripheral wall portion of the powder mixed air ejection cylinder 1. It is connected so as to communicate with the body mixing air flow path 11. A powder mixed air supply path 15 for supplying the powder mixed air M is connected to the base end of the powder mixed air supply cylinder 14, and the powder mixed air M is connected to the powder mixed air supply path 15. A powder mixing air interrupting valve 16 for interrupting and interrupting the supply and a powder mixing air supply amount adjusting valve 17 for adjusting the supply amount of the powder mixing air M are provided.

A gas fuel supply path 18 for supplying the gas fuel G is connected to the base end of the gas fuel ejection tube 10, and a gas fuel interrupt valve 19 for interrupting the supply of the gas fuel G and a gas fuel interrupt valve 19 are connected to the gas fuel supply path 18. The gas fuel supply amount adjusting valve 20 is provided so that the supply amount of the gas fuel G can be adjusted.
A tubular air supply port 21 is connected to a portion of the peripheral wall of the air ejection tube 6 on the closed end side in a state of communicating with the secondary air flow path 12, and the air supply port 21 is connected to the air supply port 21 via an air supply path 22. A blower 23 is connected to the blower 23, and the blower 23 is configured to be able to blow the secondary combustion air A into the secondary air flow path 12.
A secondary air damper 24 is provided in the air supply port 21 so that the amount of ventilation of the secondary combustion air A can be adjusted.

Then, as shown in FIG. 1, the powder combustion device configured as described above is attached to the attachment opening 27 formed in the furnace wall 26 of the heating furnace via the attachment plate 25.

Hereinafter, the control operation of the control unit 3 will be described.
The control unit 3 includes a blower 23, a gas fuel interrupt valve 19, a gas fuel supply amount adjusting valve 20, a powder mixing air interrupting valve 16, a powder mixing air supply amount adjusting valve 17, a secondary air damper 24, a tertiary air damper, and the like. It is configured to control the operation of the powder combustion apparatus by controlling the operation of the powder combustion apparatus.
On the operation panel (not shown) that transmits various control information to the control unit 3, the type of powder combustible material F to be burned is displayed in addition to the operation switch that commands the start and stop of the operation of the powder combustion device. It is equipped with a powdery combustible type setting switch to be set.

Then, the lower the combustibility of the powdery combustible material F is, the more the ratio of the combustion amount of the gas fuel G to the total combustion amount of the combustion amount of the powdery combustible material F and the combustion amount of the gas fuel G. With the gas combustion amount ratio increasing, the gas combustion amount ratio is set according to the types of the plurality of powdery combustibles F. Then, the relationship between the type of the powdery combustible material F and the gas combustion amount ratio is stored in the storage unit (not shown) of the control unit 3 as the gas combustion amount ratio information.

Incidentally, the flammability of the powdery combustible material F decreases as the amount of the flammable volatile component contained in the powdery combustible material F decreases, for example.
Then, through experiments and the like, the gas combustion amount ratio is set so that the powdery combustibles F can be stably and slowly burned for each of the plurality of types of powdery combustibles F and the generation of the local high temperature region can be sufficiently suppressed. Will be done. The lower the combustibility of the powdery combustible material F, the larger the gas combustion amount ratio needs to be in order to stably and slowly burn the powdery combustible material F. Therefore, the gas combustion amount ratio is the powdery combustible material. The lower the combustibility of F is, the larger it is, and it is set according to the types of a plurality of powdery combustible materials F. Incidentally, the gas combustion amount ratio is set, for example, in the range of 5 to 20% according to the types of the plurality of powdery combustibles F.
Examples of the type of powdery combustible material F to be burned include petro-coke fine powder, pulverized coal, organic sludge powder, waste plastic powder and the like.

Further, the mixing ratio of the powdery combustible material F and the air A in the powder mixed air M supplied through the powder mixed air supply path 15 is set to a predetermined ratio.
Further, the air ratio of the combustion air to the total combustion amount is also set to a predetermined value and stored in the storage unit of the control unit 3 as the set air ratio. By the way, the set air ratio is the amount of primary combustion air A contained in the powder mixed air M, the amount of secondary combustion air A ejected from the secondary air outlet 9, and the amount of secondary combustion air A ejected from the tertiary air outlet. The total amount of air, which is the sum of the amounts of the tertiary combustion air A, is set as the total amount of air, and is set based on the total amount of air.

The operator of the powder combustion apparatus sets the type of the powder combustible material F by the powder combustible material type setting switch, and commands the start of operation by the operation switch.
When the operation switch commands the control unit 3 to start operation, the control unit 3 operates the blower 23 with the ignition plug (not shown) activated, and opens the gas fuel interrupt valve 19 and the powder mixing air interrupt valve 16. Along with the valve, the total combustion amount becomes the set combustion amount, the air ratio becomes the set air ratio, and the gas combustion amount ratio corresponds to the type of powdery combustible material F set by the powdery combustible material type setting switch. The amount of gas fuel G ejected from the gas fuel nozzle 7, the amount of powder mixed air M ejected from the powder mixed air outlet 8, and the amount of secondary combustion from the secondary air outlet 9 so as to have the same ratio. In order to adjust the amount of air A ejected and the amount of tertiary combustion air A ejected from the tertiary air outlet, the opening degree of the gas fuel supply amount adjusting valve 20, the opening degree of the powder mixed air supply amount adjusting valve 17, The opening degree of the secondary air damper 24 and the opening degree of the tertiary air damper are adjusted.

The gas fuel supply amount adjusting valve 20 adjusts the amount of gas fuel G ejected from the gas fuel nozzle 7, and the powder mixed air supply amount adjusting valve 17 adjusts the amount of powder mixed air M ejected from the powder mixed air outlet 8. Since the gas combustion amount ratio is adjusted by adjusting the ejection amount of the gas, the gas combustion amount ratio is adjusted by the gas fuel supply amount adjusting valve 20 and the powder mixed air supply amount adjusting valve 17. The quantity ratio adjusting means V is configured.
That is, the control unit 3 is configured to control the gas combustion amount ratio adjusting means V so that the gas combustion amount ratio becomes larger as the combustibility is lower, according to the combustibility of the powdery combustible material F. It will be done.

In adjusting the opening degree of each of the secondary air damper 24 and the tertiary air damper, the control unit 3 calculates the total air amount corresponding to the set air ratio according to the set combustion amount, and also calculates the calculated total air amount. The amount of secondary combustion air A ejected from the secondary air outlet 9 and the amount of tertiary combustion air A ejected from the tertiary air outlet 9 are set, respectively, at a predetermined ratio set in advance. , The opening degree of each of the secondary air damper 24 and the tertiary air damper is adjusted so as to have the set ejection amount.

By the way, when this powder combustion device is used as a heat source for a boiler, the set air ratio is set to, for example, 1.1.
Then, the control unit 3 ejects, for example, the amount of primary combustion air A contained in the powder mixed air M and the secondary combustion air A from the secondary air ejection port 9 according to the calculated total air amount. The sum of the amounts is 0.9 minutes of the air ratio, and the amount of the tertiary combustion air A ejected from the tertiary air outlet is 0.2 minutes of the remaining air ratio. Adjust the opening degree of each of the secondary air damper 24 and the tertiary air damper.

When the operation switch commands the control unit 3 to stop the operation, the control unit 3 closes the gas fuel interrupt valve 19, the powder mixing air interrupt valve 16, the gas fuel supply amount adjusting valve 20, and the powder mixing air supply amount adjusting valve 17. Then, the secondary air damper 24 and the tertiary air damper are closed, and the blower 23 is stopped to stop the operation of the powder combustion apparatus.

Next, based on FIG. 1, a combustion mode of the powder combustion apparatus according to the first embodiment configured as described above will be described.
Gas fuel G is ejected from the central gas fuel nozzle 7, and powder mixed air M is ejected from the annular powder mixed air outlet 8 over the entire circumference of the outer circumference of the gas fuel G ejected in this way. The secondary combustion air A is ejected from the annular secondary air outlet 9 over the entire circumference of the outer peripheral portion of the powder mixed air M ejected in this manner. Further, although not shown, the tertiary combustion air is ejected from the tertiary air outlet.

The gas fuel G ejected from the gas fuel nozzle 7 is not provided with a dedicated combustion air A supply means for supplying the combustion air A so as to be in direct contact with the gas fuel G. Therefore, the gas fuel G ejected from the gas fuel nozzle 7 toward the inside of the ejection flow of the powder mixed air M burns only the air A contained in the powder mixed air M as the primary combustion air A, and produces powder. The powdery combustible material F in the body mixed air M burns the air A in the powder mixed air M as the primary combustion air A.
That is, the powder mixed air for burning the powdery combustible material F by burning the gas fuel G ejected from the gas fuel nozzle 7 by positively utilizing the air A in the powder mixed air M. Since the density of the primary combustion air A in the M can be lowered over a wide range of the jet flow of the powder mixed air M, the powdery combustible material F in the powder mixed air M can be slowly burned.

Further, in the first embodiment, an annular powder mixed air outlet 8 is provided on the outer peripheral portion of the gas fuel nozzle 7, and an annular secondary air outlet 9 is provided on the outer peripheral portion of the powder mixed air outlet 8. Is provided. As a result, the gas fuel G ejected from the gas fuel nozzle 7 is spread over as wide a range as possible inside the powder mixed air M ejected from the powder mixed air ejection port 8, and the air in the powder mixed air M is distributed. Since A can be consumed by burning the gas fuel G, the slow combustion of the powdery combustible material F in the powder mixed air M can be performed more satisfactorily.
Moreover, the secondary combustion air A ejected from the secondary air outlet 9 can be distributed over the entire circumference of the outer peripheral portion of the powder mixed air M ejected from the powder mixed air outlet 8 as much as possible. Further, since the tertiary combustion air A is supplied from the tertiary air outlet in the direction of ejection of the powder mixed air M from the powder mixed air outlet 8, the powder in the powder mixed air M It is possible to accurately prevent the shortage of combustion air in the combustible material F.

Further, the lower the combustibility of the powdery combustible material F, the larger the gas combustion amount ratio. Therefore, the lower the combustibility of the powdery combustible material F, the larger the supply amount of the gas fuel G. Since the gas fuel G can be burned in a wide range of the powder mixed air M ejected from the tip opening 1w of the powder mixed air ejection cylinder 1, the combustion flame of the gas fuel G is ignited. In the form, the powdery combustible material F in the powder mixed air M can be stably and slowly burned over a wide range regardless of the difference in combustibility.
That is, the lower the combustibility of the powdery combustible material F, the more likely the local high temperature region to occur in the direction of ejection of the powder mixed air M, but the gas fuel G is brought to the vicinity of the location where the local high temperature region is expected to occur. Since the air A in the powder mixed air M can be positively consumed by feeding in, the generation of a local high temperature region can be effectively suppressed.
Therefore, regardless of the difference in the combustibility of the powdery combustible material F, the powdery combustible material F can be stably burned, and the NOx can be reduced.

That is, the powder combustion apparatus of the first embodiment is a powder combustion method in which only the air A contained in the powder mixed air M is burned as the primary combustion air A for the gas fuel G ejected from the gas fuel nozzle 7. It is configured to run.

[Second Embodiment]
Next, the second embodiment will be described with reference to FIGS. 3 to 6.
Also in this second embodiment, the powder mixed air ejection cylinder 31 and the gas fuel ejection cylinder 31 have the same configuration as the arrangement of the powder mixed air ejection cylinder 1 and the gas fuel ejection cylinder 10 in the first embodiment. 41 is arranged, and an air ejection portion 4 is provided on the outer peripheral portion of the tip opening 31w of the powder mixing air ejection cylinder 31.

In the second embodiment, the powder mixed air ejection cylinder 31 has a rectangular tubular shape having a rectangular cross-sectional shape in the longitudinal direction of the cylinder, and the powder mixed air ejection cylinder 31 is viewed in the longitudinal direction of the cylinder. The cross-sectional shape of the air ejection cylinder 32 is provided inside the rectangular tubular air ejection cylinder 32.
As the air ejection portion 4, a secondary air injection for ejecting secondary combustion air A for burning the powdery combustible material F in the powder mixed air M ejected from the tip opening 31w of the powder mixed air ejection cylinder 31. An outlet 33 (an example of a secondary air ejection part) and a tertiary air ejection port 34 (an example of a tertiary air ejection portion) for ejecting the tertiary combustion air A are provided.
A rectangular frame-shaped secondary air outlet 33 is formed between the tip opening edge of the powder mixing air ejection cylinder 31 and the tip opening edge of the air ejection cylinder 32, and a side portion of the secondary air outlet 33 is formed. A rectangular tertiary air outlet 34 is separately provided on the outer peripheral portion of each side portion facing the one side portion.

Hereinafter, each part of the powder combustion apparatus of the second embodiment will be described.
As shown in FIGS. 3, 5 and 6, a square tubular air having a rectangular crossing shape and one end side closed on the closed end side of the peripheral wall of the square tubular air register 35 has a rectangular crossing shape. The ducts 36 are communicated with each other to form an apparatus main body 37 having a substantially L-shaped external shape in a plan view.

Two partition plates 38 are arranged side by side in the device main body 37 at intervals in the height direction of the device main body 8, and the inside of the device main body 37 is connected to the air register 35 and the air duct 36. It is divided into three square tubular spaces that are substantially L-shaped and connected to the air duct 36. A blower 39 is connected to the end of the air duct 36, and the blower 39 is configured to allow air A to be blown into each space. ing.
Of the three spaces, the central space has the largest cross-sectional area, and the spaces on both sides have approximately the same cross-sectional area.
Then, with the two partition plates 38 and the peripheral wall portions of the air register 35 and the air duct 36 in a state of being hung on the two partition plates 38, the central space of the three spaces is used as the internal space, and the air is used. The ejection tube 32 is configured.

As shown in FIGS. 3, 4 and 6, a square tubular powder mixed air ejection cylinder 31 having a base end closed inside a portion of the air ejection cylinder 32 formed by an air register 35 is provided with air. It is arranged in a state of being inserted from the closed end of the register 35.
The powder mixing air ejection cylinder 31 is composed of a square tubular cylinder body 31 m having a rectangular crossing shape and a nozzle portion 31n having a rectangular crossing shape connected to the tip thereof. The tip opening of 31n corresponds to the tip opening 31w of the powder mixing air ejection cylinder 31, and is used as the powder mixing air ejection port 40.
The nozzle portion 31n of the powder mixing air ejection cylinder 31 is provided with a throttle portion having a passage cross-sectional area narrower than that of the tip side and the base end side in a portion slightly before the powder mixing air ejection port 40 at the tip. There is.

Although not shown, the nozzle portion 31n is connected to the tip of the cylinder body portion 31m by a tilt mechanism that can be tilted toward both partition plates 38.

As shown in FIGS. 3, 4 and 6, the cylindrical gas fuel ejection cylinder 41 is inserted into the powder mixed air ejection cylinder 31 from the closed end of the powder mixed air ejection cylinder 31. Is arranged, and a gas fuel nozzle 42 is detachably attached to the tip of the gas fuel ejection cylinder 41, and the gas fuel ejection portion 2 is configured by the gas fuel nozzle 42. The gas fuel nozzle 42 has a cone shape having a larger diameter toward the tip side, and as shown in FIG. 5, the gas fuel nozzle 42 is provided with a plurality of gas fuel ejection holes 42h arranged in a circular shape on the tip surface. Although not shown, the gas fuel nozzle 42 is produced by, for example, screwing a female screw portion provided at its base end portion into a male screw portion provided at the tip end of the gas fuel ejection cylinder 41 to obtain gas fuel. It is attached to the tip of the ejection cylinder 41.

As shown in FIGS. 3 and 4, in the air ejection cylinder 32, the powder mixing air ejection cylinder 31, and the gas fuel nozzle 42, the tip opening 31w of the powder mixing air ejection cylinder 31 is the tip opening of the air ejection cylinder 32. The gas fuel nozzle 42 is arranged at substantially the same position as 32w in the longitudinal direction of the cylinder, and is arranged in a relative positional relationship in a portion slightly retracted from the tip opening 31w of the powder mixing air ejection cylinder 31.
No other member is provided in the space between the gas fuel ejection cylinder 41 and the powder mixed air ejection cylinder 31, and the entire space is the powder mixed air flow through which the powder mixed air M flows. The passage 43 is configured to eject the powder mixed air M from the powder mixed air flow path 43 from the powder mixed air outlet 40 at the tip.
That is, the gas fuel G ejected from the gas fuel nozzle 42 is not provided with a dedicated combustion air A supply means for supplying the combustion air A so as to be in direct contact with the gas fuel G. The supply source of the combustion air A for the gas fuel G ejected from the gas fuel nozzle 42 is only the powder mixed air M in which the air A is originally mixed and ejected from the powder mixed air outlet 40.

Further, a space having a rectangular frame shape across the powder mixing air ejection cylinder 31 and the air ejection cylinder 32 is used as a secondary air flow path 44 for passing the secondary combustion air A, and the secondary air flow path 44 thereof is used. The secondary combustion air A from the air flow path 44 is ejected from the secondary air outlet 33.
The spaces at both ends of the three square tubular spaces formed over the air register 35 and the air duct 36 are used as tertiary air flow paths 46 through which the tertiary combustion air A passes, and each of the spaces has a tertiary air flow path 46. The tip opening is the tertiary air outlet 34.

As shown in FIGS. 3 and 6, a powder mixed air supply port 47 is attached to the base end of the peripheral wall of the powder mixed air ejection cylinder 31, and the powder mixed air M is attached to the powder mixed air supply port 47. The powder mixed air supply path 48 is connected to the powder mixed air supply path 48, and the powder mixed air interrupt valve 49 for interrupting the supply of the powder mixed air M and the powder mixed air M are connected to the powder mixed air supply path 48. A powder mixed air supply amount adjusting valve 50 is provided so that the supply amount of the powder mixed air can be adjusted.
A gas fuel supply path 51 for supplying the gas fuel G is connected to the base end of the gas fuel ejection tube 41, and the gas fuel supply path 51 is connected to the gas fuel interrupt valve 52 for interrupting the supply of the gas fuel G, and , A gas fuel supply amount adjusting valve 53 capable of adjusting the supply amount of the gas fuel G is provided.

As shown in FIG. 5, each of the secondary air flow path 44 and each tertiary air flow path 46 is provided with a secondary air damper 54 and a tertiary air damper 55 whose ventilation amount of air A can be adjusted, respectively.

Further, although not shown, the furnace wall 57 (see FIG. 3) of the heating furnace to which the powder combustion device is attached is provided with a quaternary air outlet for ejecting the quaternary combustion air A, and the fourth air outlet is provided. A quaternary air damper for adjusting the amount of the quaternary combustion air A ejected from the secondary air outlet is provided.

As shown in FIG. 3, the powder combustion apparatus configured as described above is formed on the furnace wall 57 of the heating furnace via the mounting plate 56 in a posture in which the two tertiary air outlets 34 are arranged in the vertical direction. It is attached to the attached attachment opening 58.

Hereinafter, the control operation of the control unit 3 will be described.
The control unit 3 includes a blower 39, a gas fuel interrupt valve 52, a gas fuel supply amount adjusting valve 53, a powder mixed air interrupt valve 49, a powder mixed air supply amount adjusting valve 50, a secondary air damper 54, and a tertiary air damper 55. It is configured to control the operation of the powder combustion apparatus by controlling the operation of the quaternary air damper and the like.
The operation panel (not shown) is provided with the same operation switch as in the first embodiment, the powdery combustible type setting switch, and the like, and the storage unit of the control unit 3 is the same as in the first embodiment. Information such as gas combustion amount ratio information and set air ratio is stored in advance.

When the operation switch commands the control unit 3 to start operation, the control unit 3 operates the blower 39 with the ignition plug (not shown) operated, and opens the gas fuel interrupt valve 52 and the powder mixing air interrupt valve 49. Along with the valve, the total combustion amount becomes the set combustion amount, the air ratio becomes the set air ratio, and the gas combustion amount ratio corresponds to the type of powdery combustible material F set by the powdery combustible material type setting switch. The amount of gas fuel G ejected from the gas fuel nozzle 42, the amount of powder mixed air M ejected from the powder mixed air outlet 40, and the amount of secondary combustion from the secondary air outlet 33 so as to have the same ratio. Gas fuel supply amount adjusting valve to adjust the amount of air A ejected, the amount of tertiary combustion air A ejected from the tertiary air outlet 34, and the amount of quaternary combustion air A ejected from the quaternary air outlet 34, respectively. The opening degree of 53, the opening degree of the powder mixed air supply amount adjusting valve 50, the opening degree of the secondary air damper 54, the opening degree of the tertiary air damper 55, and the opening degree of the quaternary air damper are adjusted.

In adjusting the opening degree of each of the secondary air damper 54, the tertiary air damper 55, and the quaternary air damper, the control unit 3 has a set air ratio according to the set combustion amount, as in the first embodiment described above. In addition to calculating the total amount of air corresponding to, the amount of secondary combustion air A ejected from the secondary air outlet 33 and the tertiary air jet at a predetermined ratio set in advance according to the calculated total air amount. The amount of the tertiary combustion air A ejected from the outlet 34 and the amount of the quaternary combustion air A ejected from the quaternary air outlet are set respectively, and the secondary air damper is set so as to have each set ejection amount. 54, Adjust the opening degree of each of the tertiary air damper 55 and the quaternary air damper.

The gas fuel supply amount adjusting valve 53 and the powder mixture air supply amount adjusting valve 50 constitute a gas combustion amount ratio adjusting means V for adjusting the gas combustion amount ratio.
That is, also in this second embodiment, the control unit 3 adjusts the gas combustion amount ratio so that the gas combustion amount ratio becomes larger as the combustibility is lower, according to the combustibility of the powdery combustible material F. It is configured to control the means V.

By the way, the set air ratio is set to the same value as that of the first embodiment, for example, 1.1.
Then, the control unit 3 ejects, for example, the amount of primary combustion air A contained in the powder mixed air M and the secondary combustion air A from the secondary air outlet 33 according to the calculated total air amount. The sum of the amount and the amount of the tertiary combustion air A ejected from the tertiary air outlet 34 is the amount of the air ratio of 0.9 minutes, and the amount of the quaternary combustion air A ejected from the quaternary air outlet 34. However, the opening degrees of the secondary air damper 54, the tertiary air damper 55, and the quaternary air damper are adjusted so that the remaining air ratio is 0.2 minutes.

When the operation switch commands the control unit 3 to stop operation, the control unit 3 closes the gas fuel interrupt valve 52, the powder mixing air interrupt valve 49, the gas fuel supply amount adjusting valve 53, and the powder mixing air supply amount adjusting valve 50. Then, the secondary air damper 54, the tertiary air damper 55, and the quaternary air damper are closed, and the blower 39 is stopped to stop the operation of the powder combustion apparatus.

Next, a combustion mode of the powder combustion apparatus according to the second embodiment configured as described above will be described with reference to FIG.
The powder mixed air M is ejected from the rectangular powder mixed air outlet 40 at the tip of the powder mixed air ejection cylinder 31, and the powder mixed air outlet 40 is substantially at the center of the powder mixed air outlet 40. Gas fuel G is ejected from the gas fuel nozzle 42 at the retracted position, and is ejected from the powder mixed air outlet 40 from the secondary air outlet 33 having a rectangular frame shape over the entire circumference of the powder mixed air A. Secondary combustion air A is ejected, and on the outer periphery of the secondary combustion air A ejected in this way, the tertiary of the outer peripheral portions of the two side portions facing each other at the secondary air ejection port 33 having a rectangular frame shape. The tertiary combustion air A is ejected from the air outlet 34. Further, although not shown, the quaternary combustion air is ejected from the quaternary air outlet.

The basic combustion mode is the same as the combustion mode according to the first embodiment described above, and the gas fuel G ejected from the gas fuel nozzle 42 is positively utilized by the air A in the powder mixed air M. By burning, the density of the primary combustion air A in the powder mixed air M for burning the powdery combustible material F can be lowered over a wide range of the jet flow of the powder mixed air M, so that the powder mixed air The powdery combustible material F in M can be burned slowly.

Then, in the second embodiment, the powder mixing air ejection cylinder 31 has a square cylinder shape, and a rectangular frame-shaped secondary air ejection port 33 is provided on the outer peripheral portion of the tip opening 31w of the powder mixing air ejection cylinder 31. Is provided, and a tertiary air outlet 34 is provided on the outer peripheral portion of each of the two side portions of the secondary air outlet 33 facing each other. As a result, the powder mixed air M ejected from the powder mixed air outlet 40 at the tip of the powder mixed air ejection cylinder 31 is ejected from the secondary air outlet 33 over the entire circumference of the outer peripheral portion of the powder mixed air M as much as possible. Since the next combustion air A can be distributed, the powdery combustible material F can be uniformly burned over a wide range of the powder mixed air M ejected from the powder mixed air outlet 40. Further, to the powder mixed air M ejected from the powder mixed air outlet 40, the tertiary combustion air A is supplied from the two tertiary air outlets 34 at the tip of the ejection direction, and the quaternary combustion air A is supplied. Since the air A for quaternary combustion is supplied from the air outlet, the unburned portion of the powdery combustible material can be accurately burned.

Further, since the gas combustion amount ratio is adjusted to be larger as the combustibility of the powdery combustible material F is lower, the powder mixed air M can be burned in the same combustion mode as that of the first embodiment. Therefore, the powdery combustible material F in the powder mixed air M can be stably and slowly burned over a wide range regardless of the difference in combustibility, and the generation of a local high temperature region can be effectively suppressed. be able to.
Therefore, regardless of the difference in the combustibility of the powdery combustible material F, the powdery combustible material F can be stably burned, and the NOx can be reduced.

That is, the powder combustion apparatus of the second embodiment also has a powder combustion method in which only the air A contained in the powder mixed air M is burned as the primary combustion air A for the gas fuel G ejected from the gas fuel nozzle 42. It is configured to run.

[Another Embodiment]
(A) In the first embodiment described above, a tertiary air ejection portion for ejecting tertiary combustion air may be provided on the outer peripheral portion of the secondary air ejection port 9. In this case, for example, the tertiary air ejection portion can be provided in an annular shape so as to surround the outer circumference of the annular secondary air ejection port 9 over the entire circumference.

(B) In the second embodiment described above, the tertiary air ejection portion may be provided in a rectangular frame shape so as to surround the outer circumference of the rectangular frame-shaped secondary air ejection port 33 over the entire circumference.

(C) In the first embodiment described above, as the gas fuel nozzles 7, a plurality of gas fuel nozzles 7 having different ejection speeds of the gas fuel G can be attached to the tips of the gas fuel ejection cylinders 10, respectively. Also in the second embodiment of the above, as the gas fuel nozzle 42, a plurality of gas fuel nozzles 42 having different ejection speeds of the gas fuel G are provided so as to be attached to the tip of the gas fuel ejection cylinder 41, respectively.
Then, according to the combustibility of the powdery combustible material F, the lower the combustibility, the faster the gas fuel G is ejected. The gas fuel nozzles 7, 42 are attached to the tips of the gas fuel ejection cylinders 10, 41. You may carry out the method.
In this case, the gas combustion amount ratio is set to a constant ratio in the range of, for example, 5 to 20% regardless of the type of the powdery combustible material F.

(D) In each of the first and second embodiments described above, a NOx sensor for detecting the NOx concentration in the combustion exhaust gas discharged from the powder combustion apparatus is provided. Then, in the first embodiment, the amount of gas fuel G ejected from the gas fuel nozzle 7 is adjusted so that the NOx concentration in the combustion exhaust gas detected by the NOx sensor becomes equal to or less than a predetermined upper limit concentration. The opening degree of the gas fuel supply amount adjusting valve 20 is adjusted, and in the second embodiment, the opening degree of the gas fuel supply amount adjusting valve 53 is adjusted in order to adjust the amount of gas fuel G ejected from the gas fuel nozzle 42. It may be configured as follows.

(E) In each of the first and second embodiments described above, the gas fuel ejection speed adjusting means for adjusting the ejection speed of the gas fuel G from the gas fuel nozzles 7 and 42 is provided, and the control unit 3 is configured. Depending on the combustibility of the powdery combustible material F, the gas fuel ejection speed adjusting means is controlled so that the lower the combustibility, the faster the ejection speed of the gas fuel G from the gas fuel nozzles 7 and 42. It may be configured as follows.
The larger the opening degree of the gas fuel supply amount adjusting valves 20 and 53 and the larger the amount of gas fuel G ejected from the gas fuel nozzles 7 and 42, the faster the gas fuel G ejected from the gas fuel nozzles 7 and 42. In the first embodiment described above, the gas fuel supply amount adjusting valve 20 and in the second embodiment, the gas fuel supply amount adjusting valve 53 can be used as the gas fuel ejection speed adjusting means, respectively. it can.

In this case, as in the first and second embodiments described above, the gas combustion amount ratio information is set and stored in the storage unit of the control unit 3.
Then, in the control unit 3, the gas fuel nozzles 7 and 42 are used so that the gas combustion amount ratio corresponds to the type of the powder combustible material F set by the powder combustible material type setting switch. In order to adjust the injection amount of the gas fuel G of the above, the opening degree of the gas fuel supply amount adjusting valves 20 and 53 is adjusted.
That is, the control unit 3 supplies the gas fuel so that the lower the combustibility of the powdery combustible material F, the faster the ejection speed of the gas fuel G from the gas fuel nozzles 7 and 42. It is configured to control the amount adjusting valves 20 and 53.

(F) In the powder combustion apparatus according to the present invention, various powdery combustible materials F such as petrocoke fine powder, pulverized coal, organic sludge powder, waste plastic powder, etc. are used as the powdery combustible material F to be burned. be able to.
Further, as the gas fuel G, various city gases other than 13A and various gas fuels other than city gas can be used.
Further, the use of the powder combustion apparatus according to the present invention can be used for various purposes such as a heat source of various heating furnaces in addition to the heat source of the boiler exemplified in each of the first and second embodiments described above. ..

It should be noted that the configuration disclosed in the above embodiment (including another embodiment, the same shall apply hereinafter) can be applied in combination with the configuration disclosed in other embodiments as long as there is no contradiction. , The embodiments disclosed in the present specification are examples, and the embodiments of the present invention are not limited thereto, and can be appropriately modified without departing from the object of the present invention.

As described above, it is possible to provide a powder combustion apparatus and a powder combustion method capable of reducing NOx.

1 Cylindrical powder mixed air ejection cylinder (powder mixed air ejection cylinder)
1w Tip opening 2 Gas fuel ejection part 3 Control part (control means)
4 Air ejection part 6 Cylindrical air ejection cylinder 7 Gas fuel nozzle 7h Gas fuel ejection hole 8 Powder mixed air ejection port (annular powder mixed air ejection part)
9 Secondary air outlet (annular air outlet)
10 Gas fuel ejection cylinder 20 Gas fuel supply amount adjusting valve (gas fuel ejection speed adjusting means)
31 Square tubular powder mixed air ejection cylinder (powder mixed air ejection cylinder)
31w Tip opening 32 Square tubular air ejection tube 33 Secondary air ejection port (rectangular frame-shaped secondary air ejection part)
34 Tertiary air outlet (tertiary air outlet)
41 Gas fuel ejection cylinder 53 Gas fuel supply amount adjusting valve (gas fuel ejection speed adjusting means)
A Air F Powdery combustibles G Gas fuel M Powder mixed air V Gas combustion amount ratio adjusting means

Claims (4)

A powder combustion device that burns powdery combustibles.
A powder-mixed air ejection cylinder that ejects powder-mixed air, which is a mixture of powdery combustibles and air, from the tip opening.
It is provided with a gas fuel ejection cylinder that is arranged inside the powder mixed air ejection cylinder in the radial direction and ejects gas fuel from the gas fuel ejection portion at the tip.
The gas fuel ejection cylinder is arranged in a state in which only the powder mixed air flows through the space between the gas fuel ejection cylinder and the powder mixed air ejection cylinder, and the gas ejected from the gas fuel ejection portion. Only the air contained in the powder mixture air is burned as the fuel for primary combustion,
An air ejection portion for ejecting air for burning powdery combustibles in the powder mixed air ejected from the tip opening is provided on the outer peripheral portion of the tip opening of the powder mixing air ejection cylinder .
The amount of gas fuel burned relative to the total amount of combustion, which is the sum of the amount of combustion of powder mixed air ejected from the tip opening of the powder mixed air ejection cylinder and the amount of combustion of gas fuel ejected from the gas fuel ejection portion. Gas combustion amount ratio adjusting means for adjusting the gas combustion amount ratio, which is the ratio of
Depending on the ease of combustion of the powdery combustible material, the lower the ease of combustion, the larger the gas combustion amount ratio is set, and the gas combustion amount ratio and the type of the powdery combustible material are set. The gas combustion amount ratio adjusting means is controlled so as to have the gas combustion amount ratio corresponding to the type of powdery combustible material set by the powdery combustible material type setting switch based on the gas combustion amount ratio information indicating the relationship. A powder combustion device equipped with a control means . A powder combustion device that burns powdery combustibles.
A powder-mixed air ejection cylinder that ejects powder-mixed air, which is a mixture of powdery combustibles and air, from the tip opening.
It is provided with a gas fuel ejection cylinder that is arranged inside the powder mixed air ejection cylinder in the radial direction and ejects gas fuel from the gas fuel ejection portion at the tip.
The gas fuel ejection cylinder is arranged in a state in which only the powder mixed air flows through the space between the gas fuel ejection cylinder and the powder mixed air ejection cylinder, and the gas ejected from the gas fuel ejection portion. Only the air contained in the powder mixture air is burned as the fuel for primary combustion,
An air ejection portion for ejecting air for burning powdery combustibles in the powder mixed air ejected from the tip opening is provided on the outer peripheral portion of the tip opening of the powder mixing air ejection cylinder.
The amount of gas fuel burned relative to the total amount of combustion of the powder mixed air ejected from the tip opening of the powder mixed air ejection cylinder and the amount of gas fuel ejected from the gas fuel ejected portion. Gas fuel ejection speed adjusting means for adjusting the ejection amount of gas fuel to adjust the gas combustion amount ratio, which is the ratio of gas fuel, and adjusting the ejection speed of gas fuel from the gas fuel ejection portion.
Depending on the ease of combustion of the powdery combustible material, the lower the ease of combustion, the larger the gas combustion amount ratio is set, and the gas combustion amount ratio and the type of the powdery combustible material are set. The gas fuel ejection speed adjusting means is controlled so as to have the gas combustion amount ratio corresponding to the type of the powdery combustible material set by the powdery combustible material type setting switch based on the gas combustion amount ratio information indicating the relationship. A powder combustion device equipped with a control means . The powder mixing air ejection cylinder has a cylindrical shape.
The powder mixing air ejection cylinder is arranged inside the cylindrical air ejection cylinder, and is arranged.
The gas fuel ejection portion is composed of a gas fuel nozzle having a circular outer circumference and a plurality of gas fuel ejection holes on the tip surface in a longitudinal direction of the cylinder from the tip side of the powder mixed air ejection cylinder.
An annular powder-mixed air ejection portion for ejecting powder-mixed air is formed between the gas fuel nozzle and the tip opening edge of the powder-mixed air ejection cylinder.
The powder combustion apparatus according to claim 1 or 2 , wherein an annular air ejection portion is formed between the tip opening edge of the powder mixing air ejection cylinder and the tip opening edge of the air ejection cylinder . The powder mixing air ejection cylinder has a rectangular tubular shape with a rectangular crossing shape.
The powder mixing air ejection cylinder is provided inside a square tubular air ejection cylinder having a rectangular crossing shape.
As the air ejection portion, a secondary air ejection portion that ejects secondary combustion air that burns powdery combustibles in the powder mixed air ejected from the tip opening of the powder mixed air ejection cylinder, and a tertiary air ejection portion. A tertiary air ejection part that ejects combustion air is provided.
The secondary air ejection portion having a rectangular frame shape is formed between the tip opening edge of the powder mixed air ejection cylinder and the tip opening edge of the air ejection cylinder.
The powder combustion apparatus according to claim 1 or 2 , wherein the tertiary air ejection portion is separately provided on one side portion of the secondary air ejection portion and the outer peripheral portion of each side portion facing the one side portion .

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