JP2002235907A - Combustion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a combustion device which reduces NOx much more than a conventional one. SOLUTION: A gas supply cylinder 2 whose ends are closed is disposed in a heat chamber 1 whose ends are opened so that the ends of the cylinder 2 are protruded from the ends of the chamber 1. Combustion air A is delivered through the space between the chamber 1 and the cylinder 2 toward the axial direction of the cylinder 2. A plurality of cylindrical gas nozzles 3 for spouting a fuel gas G that flows in the cylinder 2 are provided at the end of the peripheral wall of the cylinder 2 so a to be protruded from the peripheral wall and scattered in the circumferential direction. The fuel gas G spouted from the nozzles 3 is burned while a combustion gas E resulted from the burning of the fuel gas G is circulated through a front space of the cylinder 2 and the peripheral space at the end of the cylinder 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion apparatus for reducing the amount of NOx generated.

[0002]

2. Description of the Related Art Conventionally, as a combustion apparatus for reducing NOx, as shown in FIGS. 30 and 31, a gas supply cylinder 2 having a closed end is provided inside a combustion cylinder 1 having an open end.
Is provided in a state where the tip thereof protrudes from the tip of the combustion cylinder 1 so that the combustion air A is discharged between the combustion cylinder 1 and the gas supply cylinder 2 in the axial direction of the gas supply cylinder 2. A plurality of gas ejection holes 30 for ejecting the fuel gas G flowing in the gas supply cylinder 2 are formed on the peripheral wall on the distal end side of the gas supply cylinder 2.
There has been a configuration in which holes are formed in a state of being arranged in the circumferential direction at equal intervals (for example, see Japanese Patent Application Laid-Open No. 11-337022). Between the combustion cylinder 1 and the gas supply cylinder 2, an inner peripheral edge of the baffle plate 4 formed in an annular shape is fitted to the gas supply cylinder 2 at a position retracted from the tip of the combustion cylinder 1, A plurality of air discharge ports for discharging combustion air A flowing through the combustion cylinder 1 to the baffle plate 4 in the axial direction of the gas supply cylinder 2 are provided on the baffle plate 4. 5
Are formed in the circumferential direction at equal intervals, and each air discharge port 5 is formed by a notch formed on the outer periphery of the baffle plate 4 and the inner surface of the combustion cylinder 2.

The fuel gas G is ejected from a plurality of gas ejection holes 30 arranged at equal intervals in the circumferential direction, so that a negative pressure region (a region having a pressure lower than the surroundings) is provided in the space in front of the gas supply cylinder 2. H is formed, and the fuel gas G ejected from the gas ejection holes 30 is circulated through the front space of the gas supply tube 2 which becomes the negative pressure region H as described above. By burning the fuel gas G that has been ejected, the fuel gas G is slowly burned, and low NO
x was being planned.

[0004]

SUMMARY OF THE INVENTION In a conventional combustion device,
Although the effect of reducing NOx can be obtained to some extent, it is still insufficient, and further reduction of NOx has been pursued, and there is room for improvement.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a combustion apparatus capable of further reducing NOx as compared with the related art.

[0006]

Means for Solving the Problems [Invention according to claim 1]
The characteristic configuration according to claim 1, wherein a gas supply cylinder having a closed end is provided inside the combustion cylinder having an open end, with the end of the gas supply cylinder protruding from the end of the combustion cylinder. Combustion air is configured to be discharged in the axial direction of the gas supply cylinder through the space between the combustion cylinder and the gas supply cylinder, and flows through the gas supply cylinder to the peripheral wall on the distal end side of the gas supply cylinder. A plurality of cylindrical gas nozzles for ejecting fuel gas are provided dispersed in the circumferential direction so as to protrude from the peripheral wall, a space in front of the gas supply cylinder, and a peripheral space on the tip side of the gas supply cylinder. Through, the fuel gas ejected from the cylindrical gas nozzle is burned while circulating the combustion gas produced by the fuel gas ejected from the cylindrical gas nozzle. According to the characteristic configuration of the first aspect, the fuel gas can be effectively straightened from the plurality of cylindrical gas nozzles that are provided in the circumferential direction while being protruded from the peripheral wall on the distal end side of the gas supply cylinder. By jetting in a given state, a negative pressure area is formed in the space in front of the gas supply cylinder and in the peripheral space on the distal end side of the gas supply cylinder, and the gas supply cylinder becomes a negative pressure area as described above. The fuel gas ejected from the cylindrical gas nozzle is circulated through the front space and the peripheral space on the distal end side of the gas supply cylinder, and the combustion gas is circulated to the combustion area of the fuel gas ejected from the cylindrical gas nozzle. By burning the fuel gas while flowing the gas, the fuel gas is effectively slowly burned. In other words, since the cylindrical gas nozzle can be increased in length in the axial direction with respect to the inner diameter, the fuel gas is effectively given straightness from each cylindrical gas nozzle and diffusion is suppressed. Since the gas is jetted in a state, in addition to the space in front of the gas supply cylinder, a negative space is generated around the cylindrical gas nozzles, and in the peripheral space on the distal end side of the gas supply cylinder where a plurality of cylindrical gas nozzles are provided. A pressure zone is formed and combustion gas can be circulated through the negative pressure zone. Moreover, the combustion air discharged in the axial direction of the gas supply cylinder through the space between the combustion cylinder and the gas supply cylinder is attracted to the negative pressure region formed in the peripheral space on the tip side of the gas supply cylinder. In addition, the mixing of the fuel gas and the combustion air is promoted, and the stability of combustion is improved. By the way, as in the above-described conventional combustion device, in the case where the fuel gas is ejected from the gas ejection hole formed in the peripheral wall on the tip side of the gas supply cylinder, the length of the gas ejection hole in the axial direction is smaller than the inner diameter. Is usually short, the straightness of the fuel gas ejected from the gas ejection holes is poor, and the fuel gas diffuses remarkably, and the fuel gas is ejected directly from the peripheral wall of the gas supply cylinder. No negative pressure region is formed in the peripheral space on the tip side of the cylinder. In order to improve the straightness of the injected fuel gas while securing the inner diameter of the gas ejection hole so as to obtain a desired fuel gas ejection amount, the length of the gas ejection hole in the axial direction is increased. Therefore, it is necessary to make the peripheral wall of the gas supply cylinder extremely thick. Therefore, when fuel gas is ejected from the gas ejection holes formed in the peripheral wall of the gas supply cylinder, the thickness of the peripheral wall of the gas supply cylinder is adjusted to an appropriate thickness without unnecessarily increasing the thickness of the combustion apparatus. There is a limit to improving the straightness of the fuel gas ejected from the gas ejection holes while making it practical in terms of cost and cost. Therefore, according to the characteristic configuration of the present invention, in addition to circulating the combustion gas through the space in front of the gas supply tube, it is possible to circulate the combustion gas through the peripheral space on the tip side of the gas supply tube. Since it is possible, the amount of circulating combustion gas can be increased as compared with the related art, and slow combustion can be further promoted. Therefore, it is possible to provide a combustion device capable of further reducing NOx as compared with the related art. It became so. By the way, conventionally,
Although the limit was to reduce the NOx concentration to about 60 ppm, in the present invention, the NOx concentration could be reduced to about 30 ppm. Moreover, the combustion air discharged in the axial direction of the gas supply cylinder through the space between the combustion cylinder and the gas supply cylinder is attracted to the negative pressure region formed in the peripheral space on the distal end side of the gas supply cylinder, Since the mixing with the fuel gas is promoted, the stability of combustion can be further improved as compared with the related art. Furthermore, in the case where a plurality of cylindrical gas nozzles are arranged in the circumferential direction at intervals on the peripheral wall of the gas supply cylinder so that the flame is formed in a state of being divided in the circumferential direction of the gas supply cylinder, the surface area of the flame is increased. By lowering the flame temperature, NOx can be further reduced.

According to a second aspect of the present invention, the gas ejecting direction from the cylindrical gas nozzle is positioned forward with respect to a direction perpendicular to the axis of the gas supply cylinder. That is, it is set in a tilting direction. According to the characteristic configuration of the second aspect, the fuel gas is ejected from the cylindrical gas nozzle in a direction inclined toward the downstream in the discharge direction of the combustion air discharged between the combustion cylinder and the gas supply cylinder. As a result, the collision between the fuel gas ejected from the cylindrical gas nozzle and the combustion air is suppressed, and the diffusion of the fuel gas is suppressed. Can be formed more effectively. By the way, if the direction of gas ejection from the cylindrical gas nozzle is set to a direction perpendicular to the axis of the gas supply cylinder, or a direction inclined rearward with respect to a direction perpendicular to the axis of the gas supply cylinder,
The fuel gas ejected from the cylindrical gas nozzle tends to diffuse due to collision with the combustion air, and the negative pressure state in the negative pressure region formed in the peripheral space on the tip side of the gas supply cylinder tends to be somewhat weakened. There is. Therefore, the negative pressure region is effectively formed in the peripheral space on the distal end side of the gas supply cylinder to promote the slow combustion, so that the NOx generation amount can be further reduced. It is possible to provide a specific configuration that is preferable in increasing the size.

The invention according to claim 3 is characterized in that the plurality of cylindrical gas nozzles have a plurality of types having different gas ejection directions existing in a circumferential direction of the gas supply cylinder. It is provided in the gas supply cylinder. According to the characteristic configuration of claim 3, since the plurality of cylindrical gas nozzles are provided in the gas supply cylinder in a state where a plurality of types having different gas ejection directions are present in the circumferential direction of the gas supply cylinder, In a state where the gas ejection directions of the circumferentially adjacent cylindrical gas nozzles are different, interference between the flames formed by the adjacent cylindrical gas nozzles is suppressed, so that the surface area of the flame can be further increased. Therefore, by further increasing the surface area of the flame and lowering the flame temperature, the amount of generated NOx can be further reduced, so that it is possible to provide a specific configuration preferable for increasing the effect of reducing NOx.

According to a fourth aspect of the present invention, the plurality of cylindrical gas nozzles are formed by arranging a plurality of nozzle rows arranged in the circumferential direction in the axial direction of the gas supply cylinder. In this state, it is provided on the gas supply cylinder. According to the characteristic configuration of the fourth aspect, by providing a plurality of cylindrical gas nozzles in the gas supply cylinder in a state where a plurality of nozzle rows arranged in the circumferential direction are arranged in a row in the axial direction of the gas supply cylinder. Even when the number of the cylindrical gas nozzles is large, the cylindrical gas nozzles can be provided in a state where the interval between the cylindrical gas nozzles adjacent in the circumferential direction is widened. In other words, in order to increase the range of the negative pressure region to be formed and to enhance the negative pressure state, in order to increase the gas ejection speed from the cylindrical gas nozzle and improve the straightness of the gas ejection, it is necessary to use the cylindrical gas nozzle. It is necessary to reduce the pore size,
On the other hand, since it is necessary to secure the required total gas ejection amount, while securing the total gas ejection amount, the hole diameter of the cylindrical gas nozzle is reduced to increase the gas ejection speed from the cylindrical gas nozzle. Requires a large number of cylindrical gas nozzles to be installed. When a large number of cylindrical gas nozzles are provided in the gas supply cylinder, if the gas supply cylinders are provided in a plurality of rows in the axial direction, the interval between circumferentially adjacent cylindrical gas nozzles can be increased. It is preferable when the flame is formed in a divided shape. Therefore,
Due to the synergistic effect of increasing the range of the negative pressure range and increasing the negative pressure state to increase the amount of combustion gas circulation, and the fact that the flame can be divided and the flame temperature can be reduced, Since the amount of generated NOx can be further reduced, it is possible to provide a specific configuration preferable for increasing the effect of reducing NOx.

According to a fifth aspect of the present invention, the tip of the cylindrical gas nozzle of the nozzle row located on the upstream side among the nozzle rows arranged in the axial direction is the downstream side. Is located on the radially inward side of the gas supply cylinder from the tip of the cylindrical gas nozzle of the nozzle row located at. According to the characteristic configuration of claim 5, the cylindrical gas nozzles are arranged along the axial direction, and the tip of the cylindrical gas nozzle located on the upstream side in the axial direction is located on the downstream side. Since the fuel gas is located on the radially inward side of the gas supply cylinder from the tip of the tubular gas nozzle, the combustion gas of the fuel gas burned by the tubular gas nozzle located on the upstream side is generated by the tubular gas nozzle located on the downstream side. Through the attraction of the surrounding negative pressure region, through the negative pressure region, the combustion region of the fuel gas ejected from the downstream cylindrical gas nozzle (hereinafter simply referred to as the combustion region of the downstream cylindrical gas nozzle) Slow combustion can be promoted. Therefore, the combustion gas of the fuel gas burned by the cylindrical gas nozzle located on the upstream side in the axial direction of the gas supply cylinder is attracted to the combustion region of the downstream cylindrical gas nozzle to promote slow combustion. , NO
Since the amount of x generation can be further reduced, it is possible to provide a specific configuration preferable for increasing the effect of reducing NOx.

According to a sixth aspect of the present invention, when the nozzle row is formed in two rows and the diameter of the gas supply cylinder is D, the diameter of the combustion cylinder is 1.8D.
The distance between the air discharge port and the upstream cylindrical gas nozzle is in the range of 0.4D to 0.5D,
The distance between the upstream cylindrical gas nozzle and the downstream cylindrical gas nozzle is in the range of 0.25D to 0.35D, and the length of the downstream cylindrical gas nozzle is 0.25D to 0.35D.
D, the length of the upstream cylindrical gas nozzle is three times or approximately three times the length of the downstream cylindrical gas nozzle.
It is set to double. The inventors of the present invention
As described above, it has been found that NOx can be reduced by adopting a configuration in which a plurality of cylindrical gas nozzles are provided on the peripheral wall on the distal end side of the gas supply cylinder so as to protrude from the peripheral wall and are dispersed in the circumferential direction. However, in the above-described configuration, further studies were conducted to further reduce NOx, and two nozzle rows were formed. When it is set to be in the range, the interval between the air discharge port and the upstream cylindrical gas nozzle is in the range of 0.4D to 0.5D, the upstream cylindrical gas nozzle and the downstream cylindrical gas nozzle, 0.25D
And the length of the downstream cylindrical gas nozzle is set in the range of 0.25D to 0.35D, and the length of the upstream cylindrical gas nozzle is set in the range of the downstream cylindrical gas nozzle. It has been found that setting the length to 1/3 or approximately 1/3 of the length is preferable for reducing the amount of NOx generated while stabilizing combustion and reducing the amount of generated CO. In other words, increasing the number of nozzle rows increases the range of the negative pressure range,
Although it is possible to increase the circulation amount of the combustion gas by strengthening the negative pressure state, the configuration becomes more complicated when the number of nozzle rows increases, so that both the increase in the circulation amount of the combustion gas and the simplification of the configuration are compatible. Is preferably provided with two nozzle rows. If the distance between the air discharge port and the upstream cylindrical gas nozzle is shorter than the range of 0.4D to 0.5D, the fuel gas ejected from the cylindrical gas nozzle diffuses due to collision with combustion air. And the range of the negative pressure range becomes narrower, the negative pressure state becomes weaker, and the amount of generated NOx increases. On the other hand, when the range is longer than the range of 0.4D to 0.5D, the fuel gas and the combustion are reduced. As the mixing with the working air becomes insufficient, the combustion becomes unstable and the amount of generated CO increases,
The interval between the air discharge port and the upstream cylindrical gas nozzle is 0.1 mm.
It is preferable to set within the range of 4D to 0.5D. When the interval between the upstream cylindrical gas nozzle and the downstream cylindrical gas nozzle is shorter than the range of 0.25D to 0.35D,
The amount of combustion gas generated by the upstream cylindrical gas nozzle, which is attracted to the combustion region of the downstream cylindrical gas nozzle, becomes too large, combustion becomes unstable, and the amount of generated CO increases. On the other hand, if the length is longer than the range of 0.25D to 0.35D, the amount of combustion gas induced to the combustion region of the cylindrical gas nozzle on the downstream side decreases, so that the generation amount of NOx increases and the fuel gas and combustion Since the mixing with the working air becomes insufficient and the combustion becomes unstable and the amount of generated CO increases, the interval between the upstream-side tubular gas nozzle and the downstream-side tubular gas nozzle is 0.25D to 0.25D. It is preferable to set within the range of 35D. The length of the downstream cylindrical gas nozzle is 0.25
When the length is shorter than the range of D to 0.35D, the fuel gas ejected from the cylindrical gas nozzle easily diffuses due to collision with the combustion air, and the range of the negative pressure range becomes narrower.
The negative pressure condition becomes weaker, the amount of generated NOx increases,
If the length is longer than the range of 0.25D to 0.35D, the mixing of the fuel gas and the combustion air becomes insufficient, the combustion becomes unstable, and the amount of generated CO increases. Is preferably set in the range of 0.25D to 0.35D. When the length of the upstream cylindrical gas nozzle is shorter than 1/3 of the length of the downstream cylindrical gas nozzle, the amount of combustion gas attracted to the combustion region of the downstream cylindrical gas nozzle decreases, If the generation amount of NOx increases, while if it is longer than 1/3 of the length of the downstream-side cylindrical gas nozzle, the amount of combustion gas attracted to the combustion region of the downstream-side cylindrical gas nozzle becomes too large, Since the combustion becomes unstable and the amount of generated CO increases, the length of the cylindrical gas nozzle on the upstream side is 1 / the length of the cylindrical gas nozzle on the downstream side.
It is preferably set to 3 or approximately 1/3. Therefore, even if a plurality of nozzle rows are provided, the number of rows is reduced as much as possible to simplify the configuration, while stabilizing the combustion as much as possible to reduce the amount of generated CO and also enable the slow combustion. And the NOx generation amount can be reduced.

The invention according to claim 7 is characterized in that the plurality of cylindrical gas nozzles are arranged such that the plurality of cylindrical gas nozzles having different gas ejection amounts are arranged alternately in the circumferential direction. It is provided in the supply cylinder. According to the characteristic configuration of the seventh aspect, the fuel gas ejected from the cylindrical gas nozzle having the larger gas ejection amount causes the mixture to have a large ratio of the fuel gas amount to the combustion air amount (hereinafter, the rich mixture). ) Is formed, and the fuel gas ejected from the cylindrical gas nozzle having the smaller gas ejection amount produces an air-fuel mixture (hereinafter, lean air-fuel mixture) in which the ratio of the fuel gas amount to the combustion air amount is smaller than the rich air-fuel mixture. Once formed, the rich mixture gas region and the light mixture gas region are alternately arranged in the circumferential direction, so that the so-called rich-light combustion can be performed. Therefore, the amount of NOx generated can be further reduced by lowering the flame temperature by performing the rich / lean combustion, so that it is possible to provide a specific configuration preferable for increasing the effect of reducing NOx.

[0013] According to an eighth aspect of the present invention, there is provided a fuel cell system, comprising: The arcuate portion located closer to the gas supply cylinder is formed to be inclined toward the axially rearward side of the cylindrical gas nozzle as the portion is closer to the gas supply cylinder. According to the characteristic configuration of the eighth aspect, an arc-shaped portion (hereinafter, referred to as a pair) located at a front end portion of a part or all of the plurality of cylindrical gas nozzles, which is located close to a space in front of the gas supply cylinder. The front space approach side arc-shaped portion may be referred to as an inclined portion), but a portion located closer to the gas supply cylinder is located on the rear side in the axial center direction of the cylindrical gas nozzle (hereinafter may be referred to as a rear inclined portion). So that the combustion gas that is attracted from the front of the gas supply cylinder toward the cylindrical gas nozzle in which the arc portion on the front side near the front space at the front end is formed to be inclined rearward smoothly. The fuel gas ejected from the cylindrical gas nozzle can flow into a combustion region (hereinafter, sometimes simply referred to as a combustion region of the cylindrical gas nozzle). That is, as shown in FIG. 19, when the arc-shaped portion 3 r at the front end of the cylindrical gas nozzle 3, which is located close to the space in front of the gas supply tube 2 and is close to the front space, is formed in a rearward inclined shape. As shown in FIG. 7, an arc-shaped portion located close to the space in front of the gas supply tube 2 at the distal end of the cylindrical gas nozzle 3 is formed in an orthogonal shape orthogonal to the axis of the cylindrical gas nozzle 3. The front space and the front end of the gas supply tube 2 are compared with the case where the side located near the space in front of the gas supply tube 2 at the front end of the cylindrical gas nozzle 3 is a right-angled corner. It is difficult for the combustion gas E induced toward the cylindrical gas nozzle 3 to flow into the combustion region of the cylindrical gas nozzle 3 by the negative pressure region H formed in the peripheral space of Combustion of cylindrical gas nozzle 3 You can be made to flow into the. Therefore, by promoting the slow combustion by allowing the combustion gas to smoothly flow into the combustion region of the cylindrical gas nozzle, the amount of generated NOx can be further reduced, so that
It is possible to provide a specific configuration preferable for increasing the effect of reducing NOx.

According to a ninth aspect of the present invention, the characteristic configuration according to the ninth aspect is that a part or all of the plurality of cylindrical gas nozzles is provided at a front end of the gas supply cylinder at a distal end portion. The arcuate portion that is located farther away is formed in an inclined shape that is located farther forward in the axial direction of the cylindrical gas nozzle as the portion that is farther away from the gas supply cylinder. According to the characteristic configuration of the ninth aspect, an arc-shaped portion (hereinafter referred to as “frontward”) that is located in the space in front of the gas supply cylinder at the distal end portion of a part or all of the plurality of cylindrical gas nozzles. The space-separated side arc-shaped portion may be referred to as an inclined portion (hereinafter, may be referred to as a forward-inclined portion), which is located further away from the gas supply cylinder in the axially forward side of the cylindrical gas nozzle. Since it is formed, the cylindrical gas nozzle in which the arc-shaped portion at the distal end with respect to the front space is formed to be inclined forward has a sharp-pointed portion at the distal end with respect to the space at the front. . Then, the combustion air flowing toward the cylindrical gas nozzle having the sharp-pointed portion is easily caught on the tip end side of the cylindrical gas nozzle by the sharp-pointed portion, and a vortex is easily generated. The mixing of the combustion air and the fuel gas is promoted by the vortex, and the flame holding action at the tip end surface of the cylindrical gas nozzle is improved. That is, as shown in FIG. 19, the arc-shaped portion 3 p at the distal end of the cylindrical gas nozzle 3, which is located in the space in front of the gas supply cylinder 2 and is separated from the front space, is formed in a forward inclined shape. If an acute point is provided on the distal end of the gas nozzle 3 on the side away from the front space, the negative pressure region H is likely to be formed on the distal end surface side of the cylindrical gas nozzle 3 by the action of the acute point. Combustion air A which is discharged between the cylinder 1 and the gas supply cylinder 2 and flows toward the cylindrical gas nozzle 3
Is easy to be caught from the tip of the sharp point to the tip face side, and eddy current is easily generated. On the other hand, for example, as shown in FIG. 7, the arc-shaped portion at the distal end of the cylindrical gas nozzle 3 that is separated from the front space of the gas supply cylinder 2 and separated from the front space is defined by the axis of the cylindrical gas nozzle 3. When formed in an orthogonal shape that is perpendicular to the center, and the space apart from the front space at the front end of the cylindrical gas nozzle 3 becomes a right-angled corner, a negative pressure region H is formed on the front end surface side of the cylindrical gas nozzle 3. Since it is difficult, the combustion air A is hardly caught in the tip end side of the cylindrical gas nozzle 3 and a vortex is hardly generated, which is disadvantageous in improving the flame holding effect. Therefore, the flame holding action at the tip end surface of the cylindrical gas nozzle can be promoted, and the fuel gas can be more stably burned. Therefore, it is possible to provide a specific configuration preferable for further improving the combustion stability. it can.

According to a tenth aspect of the present invention, the tip configuration of a part or all of the plurality of cylindrical gas nozzles is located close to the gas supply cylinder. The position of the cylindrical gas nozzle is formed so as to be inclined toward the rear side in the axial direction of the cylindrical gas nozzle. According to the tenth aspect of the present invention, the distal end of the cylindrical gas nozzle is formed to be inclined rearward, so that the distal end of the cylindrical gas nozzle is closer to the front space than the front end of the cylindrical gas nozzle. The arc-shaped portion is formed so as to be inclined rearward so that the combustion gas can smoothly flow into the combustion area of the cylindrical gas nozzle, and, like the invention according to the ninth aspect, the front end of the cylindrical gas nozzle with respect to the front. By forming the arc portion on the space-separation side in a forward inclined shape, an acute-angled sharp portion is provided on the tip end portion of the cylindrical gas nozzle 3 on the space-separation side with respect to the front space, and the eddy current of the combustion air flows on the tip end of the cylindrical gas nozzle. Can be effectively generated, and the flame holding action can be improved. In addition, since the distal end of the cylindrical gas nozzle is formed to be inclined backward, the area of the distal end surface of the cylindrical gas nozzle can be increased, and the flame holding action at the distal end surface of the cylindrical gas nozzle is further improved. be able to. Further, by a simple process of simply forming the distal end of the cylindrical gas nozzle in a rearwardly inclined shape, the arc-shaped portion of the distal end portion of the cylindrical gas nozzle with respect to the front space close to the rearwardly inclined shape is formed. The front space-separated side arc-shaped portion can be formed in a forward inclined shape. Therefore, with simple processing,
Slow combustion can be promoted by allowing the combustion gas to flow smoothly into the combustion area of the cylindrical gas nozzle, and the flame stabilizing action at the tip surface of the cylindrical gas nozzle is promoted to more stably burn the fuel gas. So you can
It is possible to provide a specific configuration preferable for increasing the effect of reducing NOx and further improving the stability of combustion while avoiding an increase in cost.

According to an eleventh aspect of the present invention, in the eleventh aspect, the cylindrical gas nozzle has a front-end surface in which a fuel gas is injected in a direction of an axis of the cylindrical gas nozzle. And, of the peripheral wall, a portion corresponding to the most downstream side or the most upstream side in the flow direction of the fuel gas in the gas supply tube in the gas supply tube in the circumferential direction, the fuel gas of the gas supply tube It is configured to have oblique ejection holes that eject in a direction along the axial direction of the cylindrical gas nozzle as viewed in the axial direction and along a direction inclined with respect to the axis of the cylindrical gas nozzle. It is in. According to the eleventh aspect, the fuel gas is ejected from the straight gas ejection hole of the cylindrical gas nozzle in the axial direction of the cylindrical gas nozzle, and the fuel gas is supplied from the oblique ejection hole. The fuel gas is ejected in a direction along the axial direction of the cylindrical gas nozzle as viewed in the axial direction of the cylinder and along the direction inclined with respect to the axial center of the cylindrical gas nozzle. In the gas flow direction, i.e., along the flow direction of the combustion air discharged from between the combustion cylinder and the gas supply cylinder, the fuel gas is ejected at an interval, so that the fuel gas is ejected. So-called multi-stage combustion is performed in which combustion air is dispersedly supplied at a plurality of locations along the flow direction of the combustion air. Incidentally, the oblique ejection hole is located on one of the peripheral wall of the cylindrical gas nozzle, in the peripheral direction, in a portion corresponding to the most downstream side in the gas supply cylinder in the flow direction of the fuel gas and a portion corresponding to the most upstream side. When it is formed, it becomes two-stage combustion, and when it is formed in both, it becomes three-stage combustion. In other words, the fuel gas is ejected from the rectilinear ejection holes in a state where the fuel gas is effectively given rectilinearity and diffusion is suppressed. A negative pressure area is formed in a peripheral space on the distal end side of the gas supply cylinder provided with a plurality of cylindrical gas nozzles, and the combustion gas can be circulated through the negative pressure area. A plurality of stages of combustion can be performed by the straight-direction discharging holes and the oblique-direction discharging holes, and the temperature of the flame can be further reduced. Therefore, in addition to being able to promote slow combustion, by further reducing the flame temperature by multi-stage combustion,
Further, since the amount of generated NOx can be reduced, low NOx
It is possible to provide a specific configuration preferable for increasing the effect of x conversion.

According to a twelfth aspect of the present invention, in the twelfth aspect, a plurality of air discharge ports are circumferentially arranged at intervals between the combustion cylinder and the gas supply cylinder. An air discharge port forming plate to be formed is provided. According to the characteristic configuration of claim 12, between the adjacent air discharge ports in the air discharge port forming plate, due to the combustion air discharge flow discharged from the plurality of air discharge ports arranged in the circumferential direction at intervals. Since a negative pressure region is formed in the front space of the portion, a part of the fuel gas ejected from the cylindrical gas nozzle is attracted toward the air discharge port forming plate by the attraction of the negative pressure region. Then, the induced fuel gas is mixed with the combustion air discharged from the air discharge port, and combustion starts near the air discharge port forming plate. In a state, it burns stably. Therefore, the fuel gas can be stably burned by the flame holding action by the air discharge port forming plate, so that a specific configuration preferable for further improving the stability of combustion can be provided.

According to a thirteenth aspect of the present invention, there is provided a fuel cell system according to the thirteenth aspect, wherein an inner cylinder having an open end is provided inside the gas supply cylinder with a closed portion at the end of the gas supply cylinder. A fuel gas is provided in a state where it is spaced apart, and is configured to be supplied into the gas supply cylinder from the distal end opening of the inner cylinder. According to the characteristic configuration of the thirteenth aspect, the fuel gas is supplied into the gas supply cylinder and flows through the gas supply cylinder in a state in which the fuel gas is sprayed from the distal end opening of the inner cylinder to the closed portion at the distal end of the gas supply cylinder. Since the fuel gas is ejected from each of the cylindrical gas nozzles, the closed portion at the tip of the gas supply cylinder is cooled by the sprayed fuel gas. That is, since the tip of the gas supply cylinder is inserted into a combustion chamber such as a boiler or a furnace body, the gas supply cylinder is exposed to a high-temperature atmosphere and is heated to a high temperature. By supplying the fuel gas as a cooling fluid by supplying the gas into the gas supply cylinder in a state of being sprayed on the closing part at the tip of the gas supply cylinder, the tip closing part of the gas supply cylinder is cooled and the tip closing part of the gas supply cylinder is cooled. To prevent overheating. Therefore, it is possible to prevent overheating of the gas supply cylinder without using an expensive high heat-resistant material as a material of the gas supply cylinder, thereby improving the durability of the combustion device while avoiding an increase in cost.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] A first embodiment of the present invention will be described below. As shown in FIGS. 1 and 2,
The combustion apparatus includes a cylindrical gas supply tube 2 having a closed end and a cylindrical gas supply tube 2 having a closed end protruding from the inside of a cylindrical combustion tube 1 having an open end. And the combustion air A is discharged in the axial direction of the gas supply cylinder 2 through the space between the combustion cylinder 1 and the gas supply cylinder 2,
A plurality of cylindrical gas nozzles 3 for ejecting a fuel gas G flowing through the gas supply cylinder 2 on a peripheral wall on the tip side of the gas supply cylinder 2.
Are protruded from the peripheral wall and are provided in the circumferential direction so as to be dispersed in the circumferential direction. The fuel gas G ejected from the cylindrical gas nozzle 3 is burned while circulating the combustion gas E burned by G.

An annular baffle plate 4 (corresponding to an air discharge port forming member) is provided between the combustion cylinder 1 and the gas supply cylinder 2 at a position retracted from the front end of the combustion cylinder 1. The inner peripheral edge is fitted to the gas supply cylinder 2 and the outer peripheral edge is fitted to the combustion cylinder 1, and the baffle plate 4 is provided with the combustion air A flowing through the combustion cylinder 1. The eight air discharge ports 5 for discharging in the axial direction are formed at equal intervals in the circumferential direction, and each air discharge port 5 is spaced apart from the gas supply cylinder 1 and the combustion cylinder 2 respectively. It is formed in a state in which the gas supply cylinder 2 is located in the radial direction of the gas supply cylinder 2 and is biased toward the combustion cylinder 1.

A combustion cylinder side edge 5o adjacent to the combustion cylinder 1 at the air discharge port 5 is formed in an arc shape along the inner surface of the combustion cylinder 1, and a gas supply cylinder adjacent to the gas supply cylinder 2 at the air discharge port 5 is formed. The side edge 5i is formed in an arc shape along the outer surface of the gas supply tube 2, and the circumferential edge 5s on each side in the circumferential direction of the air discharge port 5 is formed in a linear shape along the radial direction of the gas supply tube 2. I have. The baffle plate 4 forms between the air discharge ports 5 adjacent to each other in the circumferential direction, an air discharge port edge 4 s having a surface orthogonal to the axis of the gas supply cylinder 2. 5 and the gas supply cylinder 2, an arc-shaped inner edge 4 i having a surface orthogonal to the axis of the gas supply cylinder 2 is formed, and between each air discharge port 5 and the combustion cylinder 1. ,
An elongated arc-shaped outer edge 4o having a surface orthogonal to the axis of the gas supply cylinder 2 is formed. An annular recess 8 is formed by the protruding portion of the combustion cylinder 1 from the baffle plate 4, the baffle plate 4, and the gas supply cylinder 2.

An inner cylinder 9 having an open end is provided inside the gas supply cylinder 2 in a state where the end is located at a distance from a closed portion at the end of the gas supply cylinder 2. 9 is configured to supply the gas into the gas supply cylinder 2 from the opening at the tip.

The rear end of the gas supply cylinder 2 projects beyond the rear end of the combustion cylinder 1, the rear end of the inner cylinder 9 projects beyond the rear end of the gas supply cylinder 2, and the rear end of the combustion cylinder 1 and the gas supply Each rear end of the cylinder 2 is closed, and an air receiving port 1a is formed in a peripheral wall on the rear end side of the combustion cylinder 1, and combustion air A from a blower 10 is introduced into the air supply port 1a. A combustion air supply passage 11 is connected, and a fuel gas supply passage 12 through which a fuel gas G such as city gas is introduced is connected to a rear end of the inner cylinder 9.

In the first embodiment, eight cylindrical gas nozzles 3 having the same gas ejection amount are arranged in a line in the circumferential direction at equal intervals, and the peripheral wall on the tip side of the gas supply cylinder 2 is arranged. The eight cylindrical gas nozzles 3 and 8 are provided so that the cylindrical gas nozzle 3 is located at the center of the adjacent air discharge port 5 in the circumferential direction when viewed in the axial direction of the gas supply cylinder 2.
A plurality of air discharge ports 5 are provided.

The gas ejection direction of each of the cylindrical gas nozzles 3 is set so as to incline forward with respect to the direction perpendicular to the axis of the gas supply cylinder 2. In other words, the cylindrical gas nozzle 3 is formed in a straight cylindrical shape, and has a front end surface formed to be orthogonal to the axis. An outlet hole is formed, and the cylindrical gas nozzle 3 having a straight cylindrical shape is connected to the peripheral wall of the gas supply tube 2 in a state in which the axis coincides with the set gas ejection direction. It is attached.

The fuel gas G is supplied into the gas supply cylinder 2 in a state where the fuel gas G is blown from the tip of the inner cylinder 9 to the closed end of the gas supply cylinder 2, and the fuel gas G flowing through the gas supply cylinder 2 is supplied. Emitting from the eight cylindrical gas nozzles 3, supplying combustion air A into the combustion cylinder 1, and discharging the combustion air A flowing through the combustion cylinder 1 from the eight air discharge ports 5,
The fuel gas G is burned in a state where the flame F is divided into eight pieces. Further, the front end closed portion of the gas supply cylinder 2 is cooled by spraying the fuel gas G to prevent overheating.

Further, the cylindrical gas nozzle 3 is located at the center of the adjacent air discharge port 5 in the circumferential direction as viewed in the axial direction of the gas supply cylinder 2, so that the space between the adjacent combustion air discharge flows is reduced. Since the fuel gas G is ejected to the fuel cell, the fuel gas G and the combustion air A are gently mixed to perform slow combustion.

As shown in FIG. 3, the fuel gas G is radially ejected from eight cylindrical gas nozzles 3 arranged in the circumferential direction in a state in which straightness is effectively given, so that a space in front of the gas supply cylinder 2 is provided. In addition to the formation of the negative pressure region H, the negative pressure region H is also formed around each cylindrical gas nozzle 3, and also in the peripheral space on the distal end side of the gas supply tube 2. Further, the baffle plate 4 forms an arc-shaped inner edge portion 4i between each air discharge port 5 and the gas supply tube 2 and an air discharge port edge portion 4s between circumferentially adjacent air discharge ports 5. In addition, since the elongated arc-shaped outer edge 4o is formed between each air discharge port 5 and the combustion cylinder 1, a combustion air discharge flow discharged from the air discharge port 5 allows the inside of the annular recess 8 to be formed. In the baffle plate 4, a negative pressure region H is formed in the front space of each of the air discharge port edge 4 s, the outer edge 4 o, and the inner edge 4 i in the baffle plate 4.

Therefore, a part of the fuel gas G ejected from the cylindrical gas nozzle 3 is attracted to the baffle plate 4 side by the attraction of the negative pressure region H formed in the annular concave portion 8.
In the annular recess 8, the induced fuel gas G is mixed with the combustion air A discharged from the air discharge port 5, and combustion starts near the baffle plate 4.
The fuel gas G ejected from the fuel cell stably burns in a state where it is kept in flame by the baffle plate 4.

Further, a negative pressure region H formed in a space in front of the gas supply tube 2, a negative pressure region H formed in a peripheral space on the distal end side of the gas supply tube 2, and each inner region in the annular recess 8. Rim 4
i, a combustion gas E in which the fuel gas G ejected from the cylindrical gas nozzle 3 is burned by the attraction of the negative pressure region H formed in the front space of each of the air discharge opening edge 4s and each of the outer edges 4o. Is drawn into the combustion region of the fuel gas G ejected from the cylindrical gas nozzle 3. That is, the front space of the gas supply cylinder 2, the peripheral space on the tip end side of the gas supply cylinder 2, each inner edge 4 i in the annular concave portion 8, and each air discharge port edge 4.
The fuel gas G ejected from the cylindrical gas nozzle 3 is burned while the combustion gas E is circulated through the front space of each of the outer edge portions 4o and the outer edge portions 4o, thereby increasing the circulation amount of the combustion gas E and slowly. Combustion can be effectively performed.

Therefore, by forming the flame F in a divided manner, the flame temperature is reduced, and the amount of circulating the combustion gas E is increased so that the slow combustion can be effectively performed. Can be effectively reduced.

As shown in FIG. 1, assuming that the diameter of the gas supply cylinder 2 is D, the diameter B of the combustion cylinder 1 is set in the range of 1.8D to 2.3D. The distance β between the air discharge port 5 and the cylindrical gas nozzle 3 is 0.4D to 0.5D.
, The length L of the cylindrical gas nozzle 3 is 0.25D ~
It is set in the range of 0.35D. When the interval β between the air discharge port 5 and the cylindrical gas nozzle 3 is set, the position of the cylindrical gas nozzle 3 is set to the center of the hole in the portion of the cylindrical gas nozzle 3 connected to the gas supply cylinder 2.

By the way, when the combustion amount is 1300 kW,
Specifically, the diameter D of the gas supply cylinder 2 is 102 mm, the diameter B of the combustion cylinder 1 is 208 mm (2.04 D), and the interval β between the air discharge port 5 and the cylindrical gas nozzle 3 is 45 mm (0.44 D).
D), the length L of the cylindrical gas nozzle 3 is 30 mm (0.2 mm).
9D). . Further, the angle θ at which the gas ejection direction of the cylindrical gas nozzle 3 is inclined forward with respect to the direction orthogonal to the axis of the gas supply cylinder 2 (hereinafter, may be abbreviated as the forward inclination angle) θ is 30 °. It has been set.

FIG. 4 shows a combustion apparatus B constructed as described above.
The example which used S as a heat source of a boiler is shown. The boiler is provided with a number of water pipes 53 in a can body 52 forming a combustion chamber 51 therein, and an exhaust passage 54 for discharging combustion gas E in the combustion chamber 51 is connected to the can body 52 so as to be configured. The combustion device BS is attached to the can body 52 so as to burn fuel gas in the combustion chamber 51. A venturi mechanism 55 is provided in the fuel gas supply path 12 that supplies the fuel gas G to the combustion device BS, and the exhaust path 54 and the attraction portion 55a of the venturi mechanism 55 are connected by a combustion exhaust gas induction path 56, and Due to the flow of G, the flue gas E
And the fuel gas G mixed with the combustion exhaust gas E is supplied to the combustion device BS. Further, a heat exchanger 57 is provided in the flue gas induction path 56, and the heat exchanger 57 is connected to the combustion air supply path 11 that supplies the combustion air A from the blower 10 to the combustion apparatus BS. The heat exchanger 57 exchanges heat between the combustion exhaust gas E and the combustion air A, preheats the combustion air A, and supplies the preheated combustion air A to the combustion device BS.

As described above, by mixing the combustion exhaust gas E with the fuel gas G supplied to the combustion device BS, the slow combustion is more effectively caused and the NOx is further reduced. By the way, when only the fuel gas is supplied to the combustion device BS, the NOx concentration is about 30 ppm. Can be lower.

Hereinafter, each of the second to eleventh embodiments of the present invention will be described. The configuration is the same as that of the first embodiment except that the configuration related to the plurality of cylindrical gas nozzles 3 is different from the first embodiment. Therefore, for the same components and components having the same operations as those of the first embodiment, the description thereof will be omitted by assigning the same reference numerals in order to avoid redundant description, and a configuration different from that of the first embodiment will be mainly described. Will be described.

[Second Embodiment] As shown in FIGS. 5 and 6, in the second embodiment, a plurality of cylindrical gas nozzles 3 having the same gas ejection amount are arranged in a nozzle row arranged in the circumferential direction. 2 is provided in the gas supply cylinder 2 in a state of being formed in a plurality of rows in the axial direction. Specifically, the nozzle row is formed by arranging eight cylindrical gas nozzles 3 at equal intervals in the circumferential direction, and two rows of the nozzle rows are arranged in the axial direction of the gas supply cylinder 2.

In the air discharge direction from the air discharge port 5, the upstream nozzle row and the downstream nozzle row are formed by arranging the cylindrical gas nozzles 3 in the same phase in the circumferential direction.
As viewed in the axial direction of the gas supply cylinder 2, the cylindrical gas nozzles 3 of the upstream nozzle row and the cylindrical gas nozzles 3 of the downstream nozzle row are located at the center of the adjacent air discharge port 5 in the circumferential direction. Thus, 16 cylindrical gas nozzles 3 and 8 air discharge ports 5 are provided.

Of the nozzle rows arranged in the axial direction, the tip of the cylindrical gas nozzle 3 of the nozzle row located on the upstream side is
The gas supply cylinder 2 is configured to be located radially inward of the tip of the cylindrical gas nozzle 3 of the nozzle row located on the downstream side.

Further, the cylindrical gas nozzle 3 of the nozzle row on the upstream side
Is set in a direction perpendicular to the axis of the gas supply cylinder 2, and the gas ejection direction of the cylindrical gas nozzles 3 in the downstream nozzle row is set in a direction perpendicular to the axis of the gas supply cylinder 2. It is set in the direction inclined forward.

As shown in FIG. 7, in the combustion device according to the second embodiment, similarly to the combustion device according to the first embodiment, the space in front of the gas supply tube 2 and the front end side of the gas supply tube 2 are provided. , A negative pressure region H is formed in the peripheral space, and in the annular concave portion 8, a portion of the baffle plate 4 at the air discharge opening edge 4 s, a portion of the outer edge 4 o, and a portion of the inner edge 4.
A negative pressure region H is formed in the front space of each of the portions i.

Therefore, in the combustion device of the second embodiment, similarly to the combustion device of the above-described first embodiment, the cylindrical gas nozzle 3 is moved from the cylindrical gas nozzle 3 by the attraction of the negative pressure region H formed in the annular recess 8. A part of the ejected fuel gas G is attracted toward the baffle plate 4, and the attracted fuel gas G is mixed with the combustion air A discharged from the air discharge port 5 in the annular concave portion 8, and is baffled. Since combustion starts near the plate 4, the fuel gas G ejected from the cylindrical gas nozzle 3
Stable combustion is performed in a state where the flame is held by the baffle plate 4. Furthermore, in the axial direction of the gas supply cylinder 2, in the circumferential direction,
Since the cylindrical gas nozzle 3 is located at the center of the adjacent air discharge port 5 and the fuel gas G is ejected during the combustion air discharge flow, the fuel gas G and the combustion air A are Is slowly mixed to perform slow combustion.

Further, a negative pressure region H formed in a space in front of the gas supply tube 2, a negative pressure region H formed in a peripheral space on the distal end side of the gas supply tube 2, and each inner side in the annular recess 8. Rim 4
i, a combustion gas E in which the fuel gas G ejected from the cylindrical gas nozzle 3 is burned by the attraction of the negative pressure region H formed in the front space of each of the air discharge opening edge 4s and each of the outer edges 4o. Is drawn into the combustion region of the fuel gas G ejected from the cylindrical gas nozzle 3. That is, the front space of the gas supply cylinder 2, the peripheral space on the tip end side of the gas supply cylinder 2, each inner edge 4 i in the annular concave portion 8, and each air discharge port edge 4.
The fuel gas G ejected from the cylindrical gas nozzle 3 is burned while the combustion gas E is circulated through the front space of each of the outer edge portions 4o and the outer edge portions 4o, thereby increasing the circulation amount of the combustion gas E and slowly. Combustion can be effectively performed.

Further, in the combustion apparatus of the second embodiment, the nozzle rows are formed in two rows in the axial direction of the gas supply cylinder 2, and the tip of the cylindrical gas nozzle 3 in the upstream nozzle row is
Since it is configured to be located radially inward of the gas supply cylinder 2 from the tip of the cylindrical gas nozzle 3 of the nozzle row on the downstream side, combustion occurs at the cylindrical gas nozzle 3 located on the upstream side. The combustion gas E of the fuel gas G is attracted by the negative pressure region H formed around the cylindrical gas nozzle 3 located on the downstream side, and the combustion region of the downstream cylindrical gas nozzle 3 passes through the negative pressure region H. Therefore, slow combustion can be promoted. Therefore, in the combustion device of the second embodiment, since the combustion gas E from the cylindrical gas nozzle 3 on the upstream side is attracted to the combustion region of the cylindrical gas nozzle on the downstream side, slow combustion can be promoted. NOx can be further reduced as compared with the combustion device of the first embodiment.

As shown in FIG. 5, assuming that the diameter of the gas supply cylinder 2 is D, the diameter B of the combustion cylinder 1 is set in the range of 1.8D to 2.3D. The distance β between the air discharge port 5 and the upstream cylindrical gas nozzle 3 is 0.4D or more.
In the range of 0.5D, the interval α between the upstream cylindrical gas nozzle 3 and the downstream cylindrical gas nozzle 3 in the axial direction of the gas supply cylinder 2 is in the range of 0.25D to 0.35D, The length L2 of the cylindrical gas nozzle 3 is set in the range of 0.25D to 0.35D, and the length L1 of the upstream cylindrical gas nozzle 3 is reduced to 1/3 of the length of the downstream cylindrical gas nozzle L2. It has been set.

When the distance β between the air discharge port 5 and the cylindrical gas nozzle 3 is set, the position of the cylindrical gas nozzle 3 is set at the center of the hole in the portion of the cylindrical gas nozzle 3 connected to the gas supply cylinder 2. I do. When the interval α between the upstream-side cylindrical gas nozzle 3 and the downstream-side cylindrical gas nozzle 3 is set, the position of each of the upstream-side and downstream-side cylindrical gas nozzles 3 is determined by the gas supply tube 2 in the cylindrical gas nozzle 3. The center of the hole at the location connected to

By the way, when the combustion amount is 1300 kW,
Specifically, the diameter D of the gas supply cylinder 2 is 102 mm, the diameter B of the combustion cylinder 1 is 208 mm (2.04 D), and the interval β between the air discharge port 5 and the upstream cylindrical gas nozzle 3 is 45 mm.
(0.44D), the distance α between the upstream cylindrical gas nozzle 3 and the downstream cylindrical gas nozzle 3 is set to 30 mm (0.29
D), the length L2 of the downstream cylindrical gas nozzle 3 is 30 mm
(0.29D), the length L1 of the cylindrical gas nozzle on the upstream side
Is set to 10 mm. The forward inclination angle θ2 of the gas ejection direction of the downstream cylindrical gas nozzle 3 is 30 °.
Is set to

Next, as in the combustion apparatus according to the above-described second embodiment, two cylindrical nozzle rows formed by arranging eight cylindrical gas nozzles 3 having the same gas ejection amount at equal intervals in the circumferential direction are used for gas supply. In addition to being arranged in the axial direction of the cylinder 2, the gas supply cylinder 2
When viewed in the axial direction, the cylindrical gas nozzles 3 in the upstream nozzle row and the cylindrical gas nozzles 3 in the downstream nozzle row are located at the center of the adjacent air discharge port 5 in the circumferential direction. In the case, the result of verifying the effect of the installation state of each of the upstream and downstream cylindrical gas nozzles 3 on the combustion performance will be described. The installation state of the cylindrical gas nozzles 3 on the upstream side and the downstream side may be, for example, a distance between the cylindrical gas nozzle 3 on the upstream side and the cylindrical gas nozzle 3 on the downstream side (hereinafter, referred to as a space).
The nozzle interval may be abbreviated) α, the forward inclination angle θ1 in the gas ejection direction of the upstream cylindrical gas nozzle 3 (FIG. 11).
See, hereinafter, may be abbreviated as the upstream nozzle forward tilt angle), and the forward tilt angle θ2 in the gas ejection direction of the downstream cylindrical gas nozzle 3 (hereinafter, may be abbreviated as the downstream nozzle forward tilt angle). , The length of the upstream cylindrical gas nozzle 3 (hereinafter sometimes abbreviated as the upstream nozzle length) L
1 and the length L2 of the downstream cylindrical gas nozzle 3 (hereinafter, sometimes abbreviated as the downstream nozzle length) were evaluated. Further, the combustion amount of the combustion device was 1300 kW, which was the same as that exemplified in the second embodiment, and the NOx concentration and the CO concentration were evaluated under the combustion condition in which the residual oxygen concentration was 5%. That is, the diameter D of the gas supply cylinder 2 is 1
02 mm and the diameter B of the combustion cylinder 1 is 208 mm (2.04 mm).
D). The interval β between the air discharge port 5 and the upstream cylindrical gas nozzle 3 is 45 mm (0.44D).

FIG. 8 shows that the upstream nozzle forward tilt angle θ1 and the downstream nozzle forward tilt angle θ2 are each 30 °, and the upstream nozzle length L1 and the downstream nozzle length L2 are each 10 m.
In the case of m, the result of evaluating the performance by changing the nozzle interval α is shown. According to FIG. 8, the nozzle interval α is 30
The setting of about mm is optimal for lowering the NOx concentration and the CO concentration, and it can be seen that both the NOx concentration and the CO concentration increase as the distance becomes shorter and longer than 30 mm.

FIG. 9 shows that the nozzle interval α is 30 mm, the upstream nozzle length L1 and the downstream nozzle length L2 are each 10 m.
In the case of m, the results of evaluating the performance by changing the upstream nozzle forward tilt angle θ1 and the downstream nozzle forward tilt angle θ2 are shown. The upstream nozzle forward inclination angle θ1 of 0 ° corresponds to a direction in which the gas ejection direction is orthogonal to the axis of the gas supply cylinder 2. According to FIG. 9, the upstream nozzle forward tilt angle θ1 is 0 °, and the downstream nozzle forward tilt angle θ2 is 30 °.
It can be seen that setting to ° is optimal for lowering the NOx concentration and the CO concentration. Also, it can be seen that the NOx concentration tends to increase as the upstream nozzle front inclination angle θ1 increases. When the upstream nozzle front inclination angle θ is 0 °, the downstream nozzle front inclination angle θ2 is set to 30.
°, the mixing of the fuel gas and the combustion air is promoted, the combustion speed is increased, and the flame temperature is increased. Therefore, the NOx concentration is increased, and the downstream nozzle forward inclination angle θ2 is increased from 30 °. It can be seen that the larger the value, the more insufficient the mixing of the fuel gas and the combustion air, the more unstable the combustion, and the higher the CO concentration.

FIG. 10 shows a case where the nozzle interval α is 30 mm, the upstream nozzle front inclination angle θ1 is 0 °, and the downstream nozzle front inclination angle θ2 is 30 °, respectively. Let's change each L2,
The results of evaluating the performance are shown. The upstream nozzle length L1
Is 0, the gas supply cylinder 3 is provided without the cylindrical gas nozzle 3.
This corresponds to the case where a gas ejection hole is formed in the peripheral wall of. Figure 1
By setting 0, the downstream nozzle length L2 is set to 30 mm and the upstream nozzle length L1 is set to 10 mm corresponding to 1/3 of the downstream nozzle length L2, which is optimal for lowering the NOx concentration and the CO concentration. It turns out that it is. In addition, it can be seen that the NOx concentration and the CO concentration both increase when the upstream side nozzle length L1 is shorter or longer than 10 mm. Further, as the downstream side nozzle length L2 is shorter than 30 mm, the mixing of the fuel gas and the combustion air is promoted, the combustion speed is increased, and the flame temperature is increased.
It can be seen that as the Ox concentration increases and is longer than 30 mm, the mixing of the fuel gas and the combustion air becomes insufficient, the combustion becomes unstable, and the CO concentration increases.

From the result of the above verification test, as shown in the second embodiment, the upstream nozzle forward inclination angle θ
1 is 0 ° (that is, the direction in which the gas ejection direction is orthogonal to the axis of the gas supply cylinder 2), and the downstream nozzle forward inclination angle θ2 is 30.
°, the nozzle interval α is set to 30 mm (0.29D), the downstream nozzle length L2 is set to 30 mm (0.29D), and the upstream nozzle length L1 is set to 10 mm, in order to lower both NOx concentration and CO concentration. It turns out to be optimal. With this setting, the NOx concentration is reduced to 30 ppm.
And below, and the CO concentration to 10 ppm or less,
Both can be lowered.

[Third Embodiment] As shown in FIGS. 11 and 12, in the third embodiment, similarly to the second embodiment, eight cylindrical gas nozzles 3 having the same gas ejection amount are arranged at regular intervals. The two nozzle rows formed in the circumferential direction are arranged in the axial direction of the gas supply cylinder 2, and the cylindrical gas nozzles of the nozzle row on the upstream side in the circumferential direction when viewed in the axial direction of the gas supply cylinder 2. 3 and the cylindrical gas nozzle 3 in the downstream nozzle row
Are arranged at the center of the adjacent air discharge ports 5, but in each nozzle row, two types having different gas ejection directions are alternately arranged.

In the same manner as in the second embodiment, the tip of the cylindrical gas nozzle 3 of the nozzle row located on the upstream side of the nozzle rows arranged in the axial direction is the cylinder of the nozzle row located on the downstream side. The gas supply nozzle 2 is configured to be located radially inward of the gas supply tube 2 from the tip of the gas nozzle 3.

One of the two gas ejection directions having different gas ejection directions is inclined in the forward direction by 30 ° with respect to the direction perpendicular to the axis of the gas supply cylinder 2 (ie, the forward inclination direction). The angles θ1 and θ2 are set to 30 °), and the other gas ejection direction is set to a direction orthogonal to the axis of the gas supply cylinder 2 (that is, the forward inclination angles θ1 and θ2 are set to 0 °).

Therefore, in the combustion device of the third embodiment, the gas injection directions of the cylindrical gas nozzles 3 adjacent in the circumferential direction are made different to suppress the interference between the flames formed by the adjacent cylindrical gas nozzles 3. By doing so, it is possible to further increase the surface area of the flame and lower the flame temperature,
Accordingly, the amount of generated NOx can be reduced as compared with the combustion device according to the second embodiment.

When the combustion amount is 1300 kW, the diameter D of the gas supply cylinder 2 is set to 1 as in the second embodiment.
02 mm, and the diameter B of the combustion cylinder 1 is 208 mm (2.04 mm).
D), the interval β between the air discharge port 5 and the upstream tubular gas nozzle 3 is 45 mm (0.44D), and the interval α between the upstream tubular gas nozzle 3 and the downstream tubular gas nozzle 3 is 30 m.
m (0.29D), the length L of the downstream cylindrical gas nozzle 3
2 is set to 30 mm (0.29D), and the length L1 of the upstream cylindrical gas nozzle is set to 10 mm.

Fourth Embodiment As shown in FIGS. 13 and 14, in the fourth embodiment, similarly to the second embodiment, eight cylindrical gas nozzles 3 are formed at regular intervals in the circumferential direction. Are arranged in the axial direction of the gas supply cylinder 2 and, when viewed in the axial direction of the gas supply cylinder 2, the cylindrical gas nozzles 3 and the downstream nozzles of the upstream nozzle row in the circumferential direction. The tubular gas nozzles 3 in the row are arranged at the center of the adjacent air discharge ports 5, but in each nozzle row, those having different gas ejection amounts are alternately arranged. In addition, the cylindrical gas nozzle 3s with the smaller gas ejection amount
Is set to about 0.5 to 0.8 times the inner diameter of the cylindrical gas nozzle 3b having a larger gas ejection amount.

In the same manner as in the second embodiment, the tip of the cylindrical gas nozzle 3 of the nozzle row located on the upstream side of the nozzle rows arranged in the axial direction is the cylinder of the nozzle row located on the downstream side. Is configured to be located radially inward of the gas supply tube 2 from the tip of the gas supply tube 3, and the gas ejection direction of the cylindrical gas nozzle 3 in the nozzle row on the upstream side is set at the axis of the gas supply tube 2. The direction is set orthogonal to the direction, and the gas ejection direction of the cylindrical gas nozzles 3 in the downstream nozzle row is set to the direction inclined forward, with respect to the direction orthogonal to the axis of the gas supply cylinder 2.
The forward inclination angle θ2 is 30 °.

Therefore, in the combustion apparatus according to the fourth embodiment, the fuel injection amount is different in each nozzle row, and the rich mixture region and the light mixture region are alternately arranged in the circumferential direction. Since the flame temperature can be lowered by performing the concentration combustion, the generation amount of NOx can be reduced by that much compared to the combustion device in the second embodiment.

When the combustion amount is 1300 kW, the diameter D of the gas supply cylinder 2 is set to 1 as in the second embodiment.
02 mm, and the diameter B of the combustion cylinder 1 is 208 mm (2.04 mm).
D), the interval β between the air discharge port 5 and the upstream tubular gas nozzle 3 is 45 mm (0.44D), and the interval α between the upstream tubular gas nozzle 3 and the downstream tubular gas nozzle 3 is 30 m.
m (0.29D), the length L of the downstream cylindrical gas nozzle 3
2 is set to 30 mm (0.29D), and the length L1 of the upstream cylindrical gas nozzle is set to 10 mm.

[Fifth Embodiment] As shown in FIGS. 15 and 16, in the fifth embodiment, similarly to the second embodiment, eight cylindrical gas nozzles 3 having the same gas ejection amount are arranged at regular intervals. Are arranged in the axial direction of the gas supply cylinder 2 in the circumferential direction, and when viewed in the axial direction of the gas supply cylinder 2, the cylindrical shape of the nozzle row on the upstream side in the circumferential direction is viewed. Gas nozzle 3 and cylindrical gas nozzle 3 in downstream nozzle row
However, 16 cylindrical gas nozzles 3 and 8 air discharge ports 5 are provided so as to be located at the same position as the air discharge ports 5.

In the same manner as in the second embodiment, the tip of the cylindrical gas nozzle 3 of the nozzle row located on the upstream side of the nozzle rows arranged in the axial direction is the cylinder of the nozzle row located on the downstream side. Is configured to be located radially inward of the gas supply tube 2 from the tip of the gas supply nozzle 3. The direction is set orthogonal to the direction, and the gas ejection direction of the cylindrical gas nozzles 3 in the downstream nozzle row is set to the direction inclined forward, with respect to the direction orthogonal to the axis of the gas supply cylinder 2.
The forward inclination angle θ2 is 30 °.

That is, in the combustion apparatus of the fifth embodiment, the cylindrical gas nozzles 3 in the upstream nozzle row and the cylindrical gas nozzles in the downstream nozzle row in the circumferential direction when viewed in the axial direction of the gas supply cylinder 2. 3 is positioned at the same position as the air discharge port 5, and the fuel gas G is ejected so as to collide with the combustion air discharge flow. Is promoted, and combustion stability is improved. Accordingly, in the combustion device of the fifth embodiment, although the amount of NOx generated is slightly increased as compared with the combustion device of the second embodiment, the stable combustion can be performed even in a narrow combustion chamber as compared with the combustion device of the second embodiment. And the turndown ratio can be increased.

[Sixth Embodiment] As shown in FIGS. 17 and 18, in the sixth embodiment, the distal end of the cylindrical gas nozzle 3 in the nozzle row on the downstream side is located closer to the gas supply cylinder 2. By forming the rear portion of the cylindrical gas nozzle 3 in a rearwardly inclined shape located closer to the axial center of the cylindrical gas nozzle 3, the front end portion of the cylindrical gas nozzle 3 is located closer to the front space of the gas supply cylinder 2 and closer to the front space. The side arc-shaped portion 3r is formed in a rearward inclined shape, and the side arc-shaped portion 3p spaced apart from the front space of the gas supply cylinder 2 is formed in a forward inclined shape. The configuration is the same as that of the second embodiment except that the combustion cylinder 1 is provided in a posture crossing the combustion cylinder 1.

In other words, the gas supply cylinders 2 of the downstream nozzle row are tilted forward with respect to the direction perpendicular to the axis of the gas supply cylinders 2.
The tip surface 3S of the cylindrical gas nozzle 3 is provided on the peripheral wall of
The distal end surface 3S of the cylindrical gas nozzle 3 is formed in a rearward inclined shape so that is perpendicular to the axis of the gas supply cylinder 2. Then, the distal end surface 3S of the cylindrical gas nozzle 3 in the downstream nozzle row
Is formed in the rearwardly inclined shape as described above, so that the forward arcuate portion 3r with respect to the front space near the front end of the cylindrical gas nozzle 3 in the downstream nozzle row is formed in the rearwardly inclined shape, and
The arc-shaped portion 3p spaced apart from the front space is formed to be inclined forward.

The flow regulating body 13 has an opening 13o that opens concentrically with the axis of the combustion cylinder 1 and has a conical shape for guiding the combustion air A flowing through the combustion cylinder 1 toward the opening 13o. The guide surface 13c is provided. In addition, the flow regulating body 13 has a truncated conical cylindrical shape (hereinafter referred to as a frustoconical shape) in which the diameter on the large diameter side is substantially the same as the inner diameter of the combustion cylinder 1 and the diameter on the small diameter side is larger than the outer diameter of the gas supply cylinder 2. , Which may be referred to as a truncated conical cylinder).
Is provided in such a manner that the small diameter side faces the downstream side in the flow direction of combustion air and crosses the combustion cylinder 1, and the large diameter side is fitted inside the combustion cylinder 1. In other words, a truncated conical tubular rectifier 1
The small-diameter side edge of 3 and the outer peripheral surface of the gas supply cylinder 2 form an annular opening 13o that opens concentrically with the combustion cylinder 1;
The conical inner peripheral surface of the truncated conical tubular straightening body 13 functions as a conical guide surface 13c for guiding the combustion air A flowing through the combustion cylinder 1 toward the annular opening 13o. It is composed.

As shown in FIG. 19, the arc-shaped portion 3r close to the front space at the front end of the cylindrical gas nozzle 3 in the nozzle row on the downstream side is formed so as to be inclined rearward. The combustion gas E that flows from the front side of the gas supply cylinder 2 to the cylindrical gas nozzle 3 of the nozzle row on the downstream side is smoothly attracted to the negative pressure region H formed in the peripheral space on the front end side. Flows into the combustion zone of the cylindrical gas nozzle 3 in the downstream nozzle row.

The cylindrical gas nozzle 3 in the nozzle row on the downstream side
Since the arc-shaped portion 3p at the front end of the cylindrical gas nozzle 3 is formed to be inclined forward, and the front end of the cylindrical gas nozzle 3 is provided with an acute point at the space away from the front space. Since the negative pressure region H is easily formed on the tip end side of the cylindrical gas nozzle 3 by the action of the sharp portion, the negative pressure region H is discharged between the combustion cylinder 1 and the gas supply cylinder 2 and flows toward the cylindrical gas nozzle 3. The combustion air A is likely to be caught from the tip of the sharp pointed portion to the tip face side, and a vortex is easily generated. Moreover, since the distal end surface 3S of the cylindrical gas nozzle 3 is formed to be inclined rearward, the area of the distal end surface 3S of the cylindrical gas nozzle 3 can be increased, and the cylindrical gas nozzle 3 can be maintained at the distal end surface 3S. Flame action can be further improved.

Therefore, in the combustion device of the sixth embodiment, the amount of circulation of the combustion gas E can be increased and the combustion gas E Can smoothly flow into the combustion region of the cylindrical gas nozzle 3 in the downstream nozzle row, so that slow combustion can be further promoted.
NOx can be further reduced as compared with the combustion device of the second embodiment. Further, as described in the combustion device of the second embodiment, in addition to being able to stably burn the fuel gas G ejected from the cylindrical gas nozzle 3 in a state where the fuel gas G is kept in flame by the baffle plate 4, A swirl is likely to be generated at the tip of the cylindrical gas nozzle 3 in the downstream nozzle row, and the area of the tip face of the cylindrical gas nozzle 3 in the downstream nozzle row is increased to increase the flame holding area. Since the flame holding action can be further promoted, the combustion stability can be further improved as compared with the combustion apparatus of the second embodiment.

Further, as shown in FIG.
Is guided by the conical guide surface 13c of the rectifying body 13, flows so as to concentrate toward the opening 13o while suppressing a decrease in dynamic pressure, and flows out of the opening 13o, so that the cylinder The pressure is equalized in the circumferential direction, the flow rate is equalized in the circumferential direction of the cylinder, and further, flows in the combustion cylinder 1 and is discharged from the eight air discharge ports 5. Therefore, the combustion air A is evenly supplied to the fuel gas G ejected from the eight gas nozzles 3 arranged in the circumferential direction, and
Since the fuel gas G can be evenly burned by the three gas nozzles 3, stable combustion can be performed in a state where eight divided flames F having the same length are formed.

[Seventh Embodiment] As shown in FIG. 20, in the seventh embodiment, the front end of the cylindrical gas nozzle 3 in the downstream nozzle row is located close to the space in front of the gas supply cylinder 2. The closer the arc-shaped portion 3r closer to the front space to the front space is, the closer to the gas supply cylinder 2 is the cylindrical gas nozzle 3
The configuration is the same as that of the second embodiment, except that the rectifier 13 is provided in the combustion cylinder 1 in a posture crossing the combustion cylinder 1 in a rearwardly inclined shape positioned on the rear side in the axial center direction of the combustion chamber 1.

In addition, the portion of the distal end surface 1S of the cylindrical gas nozzle 3 in the nozzle row on the downstream side, which is located in the vicinity of the space in front of the gas supply cylinder 2, is formed to be inclined rearward, so that the downstream side is formed. The arc-shaped portion 3r on the front end side of the cylindrical gas nozzle 3 of the nozzle row with respect to the front space is formed so as to be inclined rearward. The rectifier 13 is configured similarly to the sixth embodiment.

Therefore, in the combustion apparatus of the seventh embodiment, the arc-shaped portion 3r at the tip end of the cylindrical gas nozzle 3 in the nozzle row on the downstream side with respect to the front space is formed to be inclined rearward. As described in the embodiment, the combustion gas E can smoothly flow into the combustion region of the cylindrical gas nozzles 3 in the downstream nozzle row, and the slow combustion can be further promoted. NOx can be further reduced as compared with the combustion device of the embodiment.
Further, by the action of the rectifier 13, similarly to the sixth embodiment, stable combustion can be performed in a state where eight divided flames F having the same length are formed.

[Eighth Embodiment] As shown in FIG. 21, in the eighth embodiment, the distal end portion of the cylindrical gas nozzle 3 of the nozzle row on the downstream side is located away from the space in front of the gas supply cylinder 2. The arc-shaped portion 3p on the side separated from the front space is formed so as to be inclined forward in the axial direction of the cylindrical gas nozzle 3 as the portion located farther from the gas supply cylinder 2 and the rectifier 13 is disposed in the combustion cylinder 1. The configuration is the same as that of the second embodiment except that it is provided in a posture crossing the combustion cylinder 1.

In addition, the portion of the distal end surface 1S of the cylindrical gas nozzle 3 in the nozzle row on the downstream side that is located in the space in front of the gas supply cylinder 2 is formed to be inclined forward, so that the downstream side can be formed. An arc-shaped portion 3p on the distal end of the cylindrical gas nozzle 3 in the nozzle row, which is spaced apart from the front space, is formed to be inclined forward. The rectifier 13 is configured similarly to the sixth embodiment.

Therefore, in the combustion apparatus according to the eighth embodiment, the arc-shaped portion 3p at the distal end of the cylindrical gas nozzle 3 in the downstream nozzle row, which is separated from the front space, is inclined forward.
Since the sharp-pointed portion is provided on the distal end of the cylindrical gas nozzle 3 on the side away from the front space, the nozzle on the downstream side is formed by the action of the sharp-pointed portion, as described in the sixth embodiment. Since a vortex is easily generated on the tip end surface of the cylindrical gas nozzles 3 in the row, and the flame holding action can be further promoted, the combustion stability can be further improved as compared with the combustion apparatus of the second embodiment. it can. In addition, the rectifier 13
In the state where eight divided flames F having the same length are formed in the same manner as described in the sixth embodiment,
Stable combustion is possible.

[Ninth Embodiment] As shown in FIG. 22, in the ninth embodiment, the distal end of the cylindrical gas nozzle 3 in the downstream nozzle row is located close to the space in front of the gas supply cylinder 2. The closer the arc-shaped part 3r closer to the front space to the front is, the closer to the gas supply cylinder 2 the cylindrical gas nozzle 3
Is formed in a rearwardly inclined shape located on the rear side in the axial center direction, and the arc-shaped portion 3p spaced apart from the front space of the gas supply tube 2 and located away from the gas supply tube 2 is located away from the gas supply tube 2. The second embodiment is the same as the second embodiment except that it is formed so as to be inclined forward in the axial direction of the cylindrical gas nozzle 3 and the rectifier 13 is provided in the combustion cylinder 1 in a posture crossing the combustion cylinder 1. It is configured similarly.

More specifically, the cylindrical gas nozzle 3 is located at the center of the distal end surface 1S of the cylindrical gas nozzle 3 in the nozzle row on the downstream side in the direction of approaching and separating from the gas supply cylinder 2.
In a state in which a portion perpendicular to the axis of is left, a portion located close to the front space of the gas supply cylinder 2 is formed in a rearward inclined shape,
Further, by forming a portion located in the front space of the gas supply cylinder 2 away from the front space in a forward inclined shape, the arc-shaped portion 3r with respect to the front space adjacent side at the tip end of the cylindrical gas nozzle 3 in the downstream nozzle row is inclined rearward. And the arc-shaped portion 3p on the side separated from the front space is formed to be inclined forward. The rectifier 13 is configured similarly to the sixth embodiment.

Therefore, in the combustion apparatus of the ninth embodiment, the arc-shaped portion 3r on the front end side of the cylindrical gas nozzle 3 in the downstream nozzle row is formed to be inclined rearward with respect to the front space. In the same manner as described in the embodiment, the combustion gas E can smoothly flow into the combustion region of the cylindrical gas nozzle 3 in the downstream nozzle row, and the slow combustion can be further promoted. NOx can be further reduced as compared with the combustion device of the embodiment.
Further, an arc-shaped portion 3p on the distal end portion of the cylindrical gas nozzle 3 in the nozzle row on the downstream side with respect to the front space is formed so as to be inclined forward, and an acute point is formed on the distal end portion of the cylindrical gas nozzle 3 with respect to the front space. As described in the sixth embodiment, the action of the sharp-pointed portion makes it easy to generate a vortex on the distal end surface of the cylindrical gas nozzle 3 of the downstream nozzle row, as described in the sixth embodiment. As a result, the flame holding action can be further promoted, so that the combustion stability can be further improved as compared with the combustion apparatus of the second embodiment. Further, by the action of the rectifier 13, similarly to the sixth embodiment, stable combustion can be performed in a state where eight divided flames F having the same length are formed.

[Tenth Embodiment] As shown in FIG.
In the tenth embodiment, the fuel gas G is applied to the distal end surface of the cylindrical gas nozzle 3 in the axial direction of the cylindrical gas nozzle 3, that is,
Forming a rectilinear jet hole 3a for jetting in a direction inclined forward with respect to a direction perpendicular to the axis of the gas supply cylinder 2, and a gas supply cylinder 2 in a circumferential direction of a peripheral wall of the cylindrical gas nozzle 3; In the portion corresponding to the most upstream side in the flow direction of the fuel gas, the fuel gas G is supplied along the axial direction of the cylindrical gas nozzle 3 when viewed in the axial direction of the gas supply cylinder 2, and An oblique ejection hole 3b that ejects in a direction along a direction inclined with respect to the axis (a direction orthogonal to the axis of the gas supply cylinder 2) is formed, and the other configuration is the same as that of the first embodiment. is there.

In each of the eight cylindrical gas nozzles 3 arranged in the circumferential direction, the fuel gas G flows in the fuel gas flow direction in the gas supply cylinder 2, that is, the combustion cylinder The fuel gas G is ejected at intervals along the flow direction of the combustion air A discharged from the space between the fuel gas 1 and the gas supply cylinder 2. The two-stage combustion is performed by being distributed and supplied at two points along the flow direction of the air A. Therefore, the flame temperature can be further reduced by the two-stage combustion. Therefore, in the combustion device of the tenth embodiment, it is possible to further reduce NOx as compared with the combustion device of the first embodiment.

[Eleventh Embodiment] As shown in FIG.
In the eleventh embodiment, the cylindrical gas nozzle 3 is provided so that the axis thereof is orthogonal to the axis of the gas supply cylinder 2, and the fuel gas G is provided on the distal end surface of the cylindrical gas nozzle 3. In a direction perpendicular to the axis of the gas supply cylinder 2, and a rectilinear ejection hole 3 c that ejects the fuel gas in the gas supply cylinder 2 in the circumferential direction of the peripheral wall of the cylindrical gas nozzle 3. At a portion corresponding to the most downstream side in the flow direction, the fuel gas G is supplied along the axial direction of the cylindrical gas nozzle 3 when viewed in the axial direction of the gas supply cylinder 2 and with respect to the axial center of the cylindrical gas nozzle 3. Oblique ejection holes 3d for ejecting in a direction along the inclined direction (the direction inclined forward with respect to the direction perpendicular to the axis of the gas supply cylinder 2) are formed, and otherwise the same as in the first embodiment. It is configured in.

In each of the eight cylindrical gas nozzles 3 arranged in the circumferential direction, the fuel gas G flows in the fuel gas flow direction in the gas supply cylinder 2, that is, the combustion cylinder The fuel gas G is ejected at intervals along the flow direction of the combustion air A discharged from the space between the fuel gas 1 and the gas supply cylinder 2. The two-stage combustion is performed by being distributed and supplied at two points along the flow direction of the air A. Therefore, the flame temperature can be further reduced by the two-stage combustion. Therefore, in the combustion device of the eleventh embodiment, it is possible to further reduce NOx as compared with the combustion device of the first embodiment.

[Another Embodiment] Next, another embodiment will be described. (A) In each of the first to eleventh embodiments, the number of the cylindrical gas nozzles 3 constituting the nozzle row is not limited to eight, and can be appropriately changed. In each of the second to ninth embodiments, the number of nozzle rows is
The number of rows is not limited to two, and three or more rows can be provided. The intervals between the cylindrical gas nozzles 3 arranged in the circumferential direction may not be equal.

Further, the above-mentioned first to fourth and sixth to eleventh
In each of the embodiments, the case where the cylindrical gas nozzle 3 is located between all the adjacent air discharge ports 5 in the circumferential direction when viewed in the axial direction of the gas supply cylinder 2 has been described. The cylindrical gas nozzle 3 may be positioned between some of the adjacent air discharge ports 5, or a plurality of cylindrical gas nozzles may be positioned between each of the adjacent air discharge ports 5. 3 may be located. In the above-described fifth embodiment, the case where the cylindrical gas nozzle 3 is provided at the same position with respect to all the air discharge ports 5 in the circumferential direction when viewed in the axial direction of the gas supply cylinder 2. However, the cylindrical gas nozzles 3 may be provided at the same position with respect to some of the air discharge ports 5, or a plurality of cylindrical gas nozzles may be provided with respect to each of the air discharge ports 5. 3 may be provided at the same position.

(B) In the third embodiment,
Although the case where two types of cylindrical gas nozzles 3 having different gas ejection directions are alternately arranged in each nozzle row is illustrated, three or more types of cylindrical gas nozzles 3 having different gas ejection directions may be arranged. Further, in the above-described third embodiment, the case where the cylindrical gas nozzles 3 having the same gas ejection direction are arranged in the same circumferential phase in the upstream and downstream nozzle rows is exemplified. The phases may be different.

(C) When the gas ejection direction of the cylindrical gas nozzle 3 is set to a direction inclined forward, with respect to a direction perpendicular to the axis of the gas supply cylinder 2, the forward inclination angle is as described above. The angle is not limited to 30 ° exemplified in each embodiment, and can be set appropriately within a range of 0 ° or more and less than 90 °. However, if the forward inclination angle is too large, mixing of the fuel gas ejected from the cylindrical gas nozzle 3 with the combustion air discharged from the air discharge port 5 becomes insufficient, and combustion becomes unstable. Because there is a tendency,
It is preferable to set the angle within a range of less than 80 °.

(D) The second, third, fifth and sixth aspects described above
In each of the ninth to ninth embodiments, the gas ejection amount of the cylindrical gas nozzles 3 in the upstream nozzle row and the gas ejection amount of the cylindrical gas nozzles 3 in the downstream nozzle row are reduced, for example, on the upstream side. As such, they may be different.

(E) When two rows of nozzle rows formed by arranging a plurality of cylindrical gas nozzles 3 in the circumferential direction at intervals are arranged side by side in the axial direction of the gas supply cylinder 2, the upstream side and the downstream side The gas ejection direction and length of each cylindrical gas nozzle 3 can be set variously. For example,
Regarding the relationship of the length of the cylindrical gas nozzle 3 between the nozzle row on the upstream side and the nozzle row on the downstream side, the upstream side is shorter than the downstream side in each of the second to fifth embodiments. Although the case has been illustrated, the upstream side and the downstream side may have the same length, or the upstream side may be longer than the downstream side.
Further, the lengths of the cylindrical gas nozzles 3 may be different in the same row.

As shown in FIG. 25, in each of the nozzle rows on the upstream side and the downstream side, the gas ejection direction of the cylindrical gas nozzle 3 is set to the front side with respect to the direction orthogonal to the axis of the gas supply cylinder 2. May be set in the direction of inclination. In that case, the forward inclination angle may be the same or different between the upstream side and the downstream side.

As shown in FIG. 26, the gas ejection direction of the cylindrical gas nozzles 3 in the nozzle row on the upstream side is set so as to be inclined rearward with respect to the direction perpendicular to the axis of the gas supply cylinder 2. , The gas ejection direction of the cylindrical gas nozzle 3 in the downstream nozzle row with respect to the direction orthogonal to the axis of the gas supply cylinder 2,
It may be set in a direction inclined forward.

As shown in FIG. 27, the gas ejection direction of the cylindrical gas nozzles 3 in the nozzle row on the upstream side is set so as to be inclined forward with respect to the direction perpendicular to the axis of the gas supply cylinder 2. Alternatively, the gas ejection direction of the cylindrical gas nozzle 3 in the downstream nozzle row may be set to a direction orthogonal to the axis of the gas supply cylinder 2.

(F) As shown in FIG. 28, a plurality of cylindrical gas nozzles 3 are provided on the peripheral wall on the tip end side of the gas supply cylinder 2 in a state of being arranged in a row in the circumferential direction at intervals. A plurality of gas ejection holes 30 may be formed on the upstream side in a state of being arranged in a row in the circumferential direction at an interval. The gas ejection holes 30 are formed in the peripheral wall of the gas supply cylinder 2. In this case, the combustion gas E of the fuel gas G burned in the gas ejection holes 30 located on the upstream side is attracted by the negative pressure region H formed around the cylindrical gas nozzle 3 located on the downstream side.
Through the negative pressure region H, the air is attracted to the combustion region of the cylindrical gas nozzle 3 on the downstream side, so that slow combustion can be promoted.

(G) In each of the second to ninth embodiments described above, two gas nozzles formed by arranging a plurality of cylindrical gas nozzles 3 in the circumferential direction at intervals are used as the gas supply cylinders 2.
When the gas supply cylinders 2 are formed side by side in the axial direction, the arrangement direction of the cylindrical gas nozzles 3 in the circumferential direction is made different between the nozzle row on the upstream side and the nozzle row on the downstream side. The configuration may be such that the cylindrical gas nozzles 3 in the upstream nozzle row are located between the cylindrical gas nozzles 3 adjacent in the circumferential direction in the nozzle row on the side.

(H) In the sixth embodiment, in forming the distal end surface 3S of the cylindrical gas nozzle 3 in a rearward inclined shape, the inclined distal end surface 3 with respect to the axis of the cylindrical gas nozzle 3 is formed.
The angle of S can be set as appropriate. As illustrated in the sixth embodiment, instead of setting the angle such that the distal end face 3S faces directly in front of the gas supply cylinder 2 in the axial direction, for example, as shown in FIG. The angle may be set so as to face the side, or may be set to face the opposite side of the gas supply cylinder 2 though not shown.

(I) In the sixth embodiment, the distal end surface of the cylindrical gas nozzle 3 in the nozzle row on the upstream side is also formed to be inclined backward, so that the gas supply cylinder 2 at the distal end of the cylindrical gas nozzle 3 The arc-shaped portion 3r close to the front space and located close to the front space is formed to be inclined rearward, and the arc-shaped portion 3p spaced apart to the front space of the gas supply cylinder 2 and separated from the front space is inclined forward. May be formed. In each of the above-described seventh to ninth embodiments, the arc-shaped portion 3r with respect to the front space adjacent to the front space is formed in the front-end portion of the cylindrical gas nozzle 3 of the nozzle row on the upstream side so as to be inclined rearward. The space-separated side arc-shaped portion 3p may be formed to be inclined forward.

(G) In the same configuration as the first, third and fourth embodiments, the distal end face 1S of the cylindrical gas nozzle 3 is formed to be inclined backward, and the distal end of the cylindrical gas nozzle 3 is formed. The arc-shaped portion 3r on the side closer to the front space and the arc-shaped portion 3p may be formed on the rear side and the arc-shaped portion 3p on the space separated from the front space.

(L) The rearwardly inclined portion 3r of the front end of the cylindrical gas nozzle 3 with respect to the space adjacent to the front space and the arcuate portion 3p of the frontward inclination with respect to the space separated from the front space are only the peripheral wall of the cylindrical gas nozzle 3. Is formed in an inclined shape (bow shape having a chord) and in a state formed in an inclined shape from the gas ejection hole of the cylindrical gas nozzle 3 to the peripheral wall of the cylinder.

(E) In each of the tenth and eleventh embodiments, the flow direction of the fuel gas G in the gas supply cylinder 2 in the circumferential direction of the peripheral wall of the cylindrical gas nozzle 3 is defined as the oblique ejection hole. Formed on one of the part corresponding to the most downstream side and the part corresponding to the most upstream side,
Although the case where the two-stage combustion is performed has been described as an example, it may be configured to perform the three-stage combustion by forming both the portion corresponding to the most downstream side and the portion corresponding to the most upstream side. In each of the first to ninth embodiments, the cylindrical gas nozzle 3 may be provided with oblique ejection holes 3b, 3d as exemplified in the tenth or eleventh embodiments. .

(B) The number and shape of the air discharge ports 5 formed in the baffle plate 4 can be changed as appropriate. For example, as the shape of the air discharge port 5, various shapes such as a circle, an oval, and a rectangle can be adopted. Further, the baffle plate 4 may be formed in a perforated plate shape having a number of small air discharge holes. Further, the baffle plate 4 may be omitted.

(F) In each of the above embodiments, the inner cylinder 9 may be omitted and the fuel gas G may be directly supplied to the gas supply cylinder 2.

(G) The combustion apparatus according to the present invention includes various furnaces and the like in addition to the boiler exemplified in the above embodiment.
It can be used in various applications.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view of a combustion device according to a first embodiment.

FIG. 2 is a front view of the combustion device according to the first embodiment.

FIG. 3 is a side view of the vicinity of the tip of a gas supply cylinder showing a combustion state of the combustion device according to the first embodiment.

FIG. 4 is a diagram showing an overall schematic configuration of a boiler provided with a combustion device according to the first embodiment.

FIG. 5 is a longitudinal sectional side view of a combustion device according to a second embodiment.

FIG. 6 is a front view of a combustion device according to a second embodiment.

FIG. 7 is a side view of the vicinity of the tip of a gas supply cylinder showing a combustion state of a combustion device according to a second embodiment.

FIG. 8 is a diagram showing a relationship between nozzle intervals and NOx concentration and CO concentration.

FIG. 9 is a diagram showing a relationship between an upstream nozzle forward tilt angle and a downstream nozzle forward tilt angle, and NOx concentration and CO concentration.

FIG. 10 shows the upstream nozzle length and the downstream nozzle length;
Diagram showing the relationship between NOx concentration and CO concentration

FIG. 11 is a front view of a combustion device according to a third embodiment.

FIG. 12 is a view taken along the arrow II in FIG. 11;

FIG. 13 is a longitudinal sectional side view of a main part of a combustion device according to a fourth embodiment.

FIG. 14 is a front view of a combustion device according to a fourth embodiment.

FIG. 15 is a longitudinal sectional side view of a main part of a combustion device according to a fifth embodiment.

FIG. 16 is a front view of a combustion device according to a fifth embodiment.

FIG. 17 is a longitudinal sectional side view of a combustion device according to a sixth embodiment.

FIG. 18 is a front view of a combustion device according to a sixth embodiment.

FIG. 19 is a side view of the vicinity of the tip of a gas supply cylinder showing a combustion state of a combustion apparatus according to a sixth embodiment.

FIG. 20 is a longitudinal sectional side view of a combustion device according to a seventh embodiment.

FIG. 21 is a longitudinal sectional side view of a combustion device according to an eighth embodiment.

FIG. 22 is a longitudinal sectional side view of a combustion device according to a ninth embodiment.

FIG. 23 is a longitudinal sectional side view of a combustion device according to a tenth embodiment.

FIG. 24 is a longitudinal sectional side view of a combustion device according to an eleventh embodiment.

FIG. 25 is a longitudinal sectional side view of a main part of a combustion device according to another embodiment.

FIG. 26 is a longitudinal sectional side view of a main part of a combustion device according to another embodiment.

FIG. 27 is a longitudinal sectional side view of a main part of a combustion device according to another embodiment.

FIG. 28 is a longitudinal sectional side view of a main part of a combustion device according to another embodiment.

FIG. 29 is a longitudinal sectional side view of a main part of a combustion device according to another embodiment.

FIG. 30 is a longitudinal sectional side view of a main part of a conventional combustion device.

FIG. 31 is a longitudinal sectional front view of a conventional combustion device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Combustion cylinder 2 Gas supply cylinder 3 Cylindrical gas nozzle 3a, 3c Straight-direction ejection hole 3b, 3d Oblique ejection hole 3p Arc-shaped portion 3r Arc-shaped portion 4 Air discharge port forming body 5 Air discharge port 9 Inner cylinder A Combustion air E Combustion Gas G Fuel gas

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Makoto Hirano 4-1-2, Hirano-cho, Chuo-ku, Osaka-shi, Osaka Inside Osaka Gas Co., Ltd. (72) Inventor Hirohiro Ogura Hirano-cho, Chuo-ku, Osaka-shi, Osaka F-term (reference) in Osaka Gas Co., Ltd. 3 1-2 chome 3K019 AA06 BA02 BB04 BB05 BD01

Claims (13)

[Claims] 1. A gas supply cylinder having a closed end is provided inside a combustion cylinder having an open end, with the end protruding from the end of the combustion cylinder. Combustion air is configured to be discharged in the axial direction of the gas supply cylinder through a space between the gas supply cylinder and a fuel gas flowing through the gas supply cylinder to the peripheral wall on the distal end side of the gas supply cylinder. A plurality of cylindrical gas nozzles are provided dispersed in the circumferential direction in a state of protruding from the peripheral wall. While circulating the combustion gas burned by the fuel gas ejected from the gas nozzle,
A combustion device configured to burn fuel gas ejected from the cylindrical gas nozzle. 2. The combustion apparatus according to claim 1, wherein a direction in which the gas is ejected from the cylindrical gas nozzle is set to a direction inclined forward with respect to a direction orthogonal to an axis of the gas supply cylinder. 3. The gas supply cylinder according to claim 1, wherein the plurality of cylindrical gas nozzles are provided in the gas supply cylinder in a state where a plurality of types having different gas ejection directions are present in a circumferential direction of the gas supply cylinder.
Or the combustion device according to 2. 4. The gas supply cylinder according to claim 1, wherein the plurality of cylindrical gas nozzles are provided in the gas supply cylinder in a state where a plurality of nozzle rows arranged in a circumferential direction are arranged in a row in an axial direction of the gas supply cylinder. 4. The combustion device according to any one of items 3 to 5. 5. The method according to claim 1, wherein the nozzle row is arranged in the axial direction.
The tip of the cylindrical gas nozzle of the nozzle row located on the upstream side,
The combustion apparatus according to claim 4, wherein the combustion apparatus is configured to be located radially inward of the gas supply cylinder from a tip of a cylindrical gas nozzle of a nozzle row located downstream. 6. The nozzle row is formed in two rows, and assuming that the diameter of the gas supply cylinder is D, the diameter of the combustion cylinder is in the range of 1.8D to 2.3D, and the air discharge port and the upstream 0.4D to 0.5D distance from the cylindrical gas nozzle
The distance between the cylindrical gas nozzle on the upstream side and the cylindrical gas nozzle on the downstream side is in the range of 0.25D to 0.35D, and the length of the cylindrical gas nozzle on the downstream side is 0.25D.
０．３0.35D, and the length of the upstream cylindrical gas nozzle is one of the length of the downstream cylindrical gas nozzle.
The combustion device according to claim 5, wherein the ratio is set to / 3 or approximately 1/3. 7. A state in which the plurality of cylindrical gas nozzles are arranged in a circumferential direction in such a manner that nozzles having different gas ejection amounts are alternately positioned and arranged in a circumferential direction.
The combustion device according to claim 1, wherein the combustion device is provided in the gas supply cylinder. 8. An arc-shaped portion, which is located close to a space in front of the gas supply cylinder, at a tip portion of a part or all of the plurality of cylindrical gas nozzles is close to the gas supply cylinder. The combustion device according to any one of claims 1 to 7, wherein the position of the cylinder is formed so as to be inclined toward the rear side in the axial direction of the cylindrical gas nozzle as being located. 9. An arc-shaped portion, which is located in a space in front of the gas supply cylinder at a tip portion of a part or all of the plurality of cylindrical gas nozzles, is located apart from the gas supply cylinder. The combustion device according to any one of claims 1 to 8, wherein a portion to be formed is formed so as to be inclined toward an axially forward side of the cylindrical gas nozzle. 10. A tip portion of a part or all of the plurality of cylindrical gas nozzles is located closer to the gas supply cylinder in a position closer to the gas supply cylinder in an axially rearward direction of the cylindrical gas nozzle. 9. The device according to claim 8, which is formed to be inclined.
Or the combustion device according to 9. 11. The cylindrical gas nozzle has, at a tip end surface thereof, a straight-moving jet hole for jetting fuel gas in the axial direction of the cylindrical gas nozzle, and the gas in a circumferential direction of a peripheral wall thereof. At a portion corresponding to the most downstream side or the most upstream side in the flow direction of the fuel gas in the supply cylinder, the fuel gas is supplied along the axial direction of the cylindrical gas nozzle when viewed in the axial direction of the gas supply cylinder. The combustion device according to any one of claims 1 to 10, further comprising an oblique ejection hole that ejects in a direction along a direction inclined with respect to an axis of the cylindrical gas nozzle. 12. An air discharge port forming plate for forming a plurality of air discharge ports arranged in a circumferential direction at intervals between the combustion cylinder and the gas supply cylinder.
The combustion device according to any one of claims 11 to 11, wherein 13. An internal cylinder having an open front end is provided inside the gas supply cylinder in a state where the front end of the inner cylinder is spaced from a closed portion of the front end of the gas supply cylinder, and the fuel gas is provided. The combustion device according to any one of claims 1 to 12, wherein the combustion device is configured to be supplied into the gas supply tube from a distal end opening of the inner tube.