JP2739746B2 - Burner for slurry fuel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a coal water slurry (CW).
M) etc. relates to a burner used for a slurry fuel.

[0002]

2. Description of the Related Art FIGS. 3 and 4 show a conventional burner for slurry fuel. FIG. 3 is a cross-sectional view when a ceramic sleeve is attached or screwed to the inner wall of the burner plate and the burner chip, and FIG. 4 is a cross-sectional view when only alloy tool steel is used for the burner plate and the burner chip. is there. As shown in FIGS. 3 and 4, a conventional burner for handling high-concentration coal water slurry fuel has a burner plug 1, a burner plate 4, and a burner chip 7 integrated with each other. Fuel supply hole 2
And a spray medium supply hole 3 through which a spray medium of steam flows. A burner plate 4 has a slurry fuel distribution chamber 5,
A first mixing chamber 6 communicating with the spray medium supply hole 3 and a guide hole 5a for mixing the slurry fuel with the spray medium are provided. Further, the burner chip 7 is provided with injection holes 9 on the front surface so as to be scattered in the circumferential direction.

[0003]

In the above-mentioned conventional burner, as shown in FIG. 4, the burner plug 1, the burner plate 4, and the burner chip 7 are all made of alloy tool steel (SKD) material used in an oil burner. It is usually done. Where the slurry fuel collides or squeezes at high speed, it tends to wear. In particular, the slurry fuel distribution chamber 5 and the conducting hole 5a of the burner plate 4 are where the slurry fuel flows at a high speed, and the plurality of first mixing chambers 6 blow the slurry fuel onto the high-speed spray medium through the plurality of conducting holes 5a. It is about to expand. In particular, the injection hole 9 is where the slurry fuel mixed with the spray medium strikes at a high speed, and the wear at such a location is so severe that the alloy tool steel alone is used, so that the service life is extremely short, about ten and several hours, and cannot be put to practical use.

For this reason, the first portion in the burner plate 4 is provided so that the wear resistance of the above-mentioned severely worn portions can be improved, and the whole can be provided with thermal shock resistance so that the life can be greatly extended. In the mixing chamber 6, the inner wall of the conducting hole 5a, the inner wall of the slurry fuel distribution chamber 5, and the inner wall of the injection hole 9 of the burner chip 7, etc. There is known a configuration in which the sleeve 12b is attached by using an inorganic adhesive or a screw. However, the vicinity of the injection hole 9 at which the slurry fuel mixed with the spray medium strikes at a high speed is a place where the wear is particularly severe.
Even if the life can be prolonged, the silicon carbide-based ceramic forming the sleeve 12b gradually wears and becomes thinner, and finally the alloy tool steel or trisilicon tetranitride-based ceramic as a base material is exposed and sprayed. The adhesive is eluted by the steam for use, or a large stress is generated due to a difference in thermal deformation due to the use of dissimilar materials for the base material and the sleeve 12b, and the silicon carbide ceramics constituting the sleeve 12b is broken. As a result, there has been a problem that inconveniences such as rattling and dropout occur.

In order to solve such a problem, a burner for preventing a slurry fuel mixed with a spray medium ejected from the burner plate 4 into the burner chip 7 from directly hitting an inner wall surface in the burner chip 7 is used. It has also been proposed that the mixture of the spray medium and the slurry fuel ejected from the plurality of first mixing chambers 6 provided in the plate 4 intersect in the burner chip 7. It did not lead to complete resolution of problems such as omissions.

The present invention focuses on the above-mentioned conventional problems, and aims to eliminate cracks, looseness and slippage due to elution of an adhesive between a base material and a sleeve or a difference in thermal deformation. It is an object of the present invention to intermix and mix the fuel mixture of the fuel and the spraying medium in the burner chip and to improve the wear resistance by integrally forming the ceramics.

[0007]

In order to achieve the above object, a slurry fuel burner according to the present invention comprises a burner plug for distributing and supplying a spray medium such as fuel and steam. A slurry burner plate provided with a burner plate having a mixing passage formed therein, the burner plate having a mixing chamber for receiving the mixed fuel introduced from the mixing passage, and a burner chip having an injection hole for the mixed fuel provided therein. In the burner, the passage axis of the mixing passage for introducing the mixed fuel into the mixing chamber intersects inside the mixing chamber, and the position of the intersection is the distance between the intersection and the tip end face of the burner chip within the interior of the burner chip. Set to be between 0.5 and 0.8 with respect to the axial length,
Further, the burner chip and the burner plate were each made of the same material ceramics.

[0008]

In the burner for a slurry fuel according to the present invention, the slurry-like fuel fed from the fuel supply hole of the burner plug to the mixing chamber of the burner plate is mixed with the spray medium and fed into the burner chip. It is further mixed inside and sprayed from the injection hole and burned. The mixed fuel ejected from the plurality of mixing chambers crosses inside the burner chip. For this reason, the mixed fuel collides violently in the burner tip, is uniformly dispersed, is sufficiently mixed, and is ejected from the injection hole. In this case, the mixed fuel ejected from the mixing chamber collides with each other in the burner chip and is evenly dispersed, so that the fuel collides with the inner surface of the burner chip at a speed lower than the speed when the fuel is ejected from the mixing chamber. , Burner tip wear is significantly reduced. Further, since the mixing in the burner chip is sufficiently performed, the spray concentration becomes uniform. Further, since a vigorous stirring action occurs in the burner chip, the slurry flowing along the inner wall of the burner chip is sufficiently sheared to form a thin film, thereby preventing generation of coarse particles during spraying.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 and 2 are explanatory views showing an embodiment of the present invention, in which the same parts as those in FIGS. 3 and 4 are denoted by the same reference numerals.

In this embodiment, a total of six first mixing chambers 6 are provided in the burner plate 4 at equally spaced positions in the circumferential direction. The first mixing chambers 6 extend obliquely inward toward the second mixing chamber 8, and the extension lines of the first mixing chambers 6 intersect in the second mixing chamber 8. In this embodiment, in order to secure a sufficient dispersion, mixing and stirring area, the position of the intersection C is determined by setting the distance 1 between C and the tip end face of the burner chip 7 to the length L inside the burner chip 7. For 1
It is preferred that / L be between 0.5 and 0.8.

The burner chip 7 is provided with a total of eight injection holes 9 at equally spaced positions in the circumferential direction. In this embodiment, the burner plug 1 is formed by a coaxial combination of a central pipe member 1A and an outer pipe member 1B. A flange portion 1a is provided on the distal end side of the central tube member 1A, and the flange portion 1a is superimposed on the burner plate 4. CWM is supplied from the conduit 12 to the fuel supply hole 2 in the central pipe member 1A, and steam is supplied to the spray medium supply hole 3 between the central pipe member 1A and the outer pipe member 1B. In the embodiment of FIG. 1, the portion of the first mixing chamber 6 upstream of the conducting hole 5a has a smaller diameter, and the second mixing chamber 8 side has a larger diameter.

In the present invention, the material of the burner plate 4 and the burner chip 7 may be made of trisilicon tetranitride ceramics having excellent thermal shock resistance or silicon carbide ceramics disturbed in wear resistance. Good. Alternatively, trisilicon tetranitride-based ceramics may be used for the burner plate 4 and silicon carbide-based ceramics may be used for the burner chip 7, or vice versa. Reference numeral 10 denotes a chip nut for fixing the burner plug 1, the burner plate 4, and the burner chip 7 from the outer periphery.

In the thus configured slurry fuel burner, the slurry-like fuel fed from the fuel supply hole 2 of the burner plug 1 to the first mixing chamber 6 via the fuel distribution chamber 5 of the burner plate 4 is not used. Is mixed with the spray medium fed from the spray medium supply hole 3 of the burner plug 1 to the first mixing chamber 6 of the burner plate 4 and fed to the second mixing chamber 8 of the burner chip. It is further mixed and sprayed from the injection holes 9 and burned. Thus, the mixture ejected from the plurality of first mixing chambers 6 crosses in the second mixing chamber 8. For this reason, the mixture collides violently in the second mixing chamber 8 and is uniformly dispersed, and after being sufficiently mixed, is ejected from the injection hole 9.

In this case, the mixture ejected from the first mixing chamber 6 collides with each other in the second mixing chamber 8 and is evenly dispersed. Also collides with the inner surface of the burner chip 7 at a low speed, so that wear of the burner chip 7 is significantly reduced. Further, since the mixing in the second mixing chamber 8 is sufficiently performed, the spray concentration becomes uniform.

Further, in the second mixing chamber 8, FIG.
As shown in (1), a vigorous stirring action is caused by the collision of the ejected substances from the first mixing chamber 6, so that the slurry flowing along the inner wall of the second mixing chamber 6 is sufficiently sheared into a thin film. The generation of coarse particles during spraying is prevented. In the present invention, it is preferable to send water, steam or air to the fuel supply hole 2 after the slurry fuel burner has stopped burning to barge the residue. In the experiment of the present inventor, the life of the burner plate 4 and the burner chip 7 was as long as about 7000 hours or more when the slurry fuel was used.

[0016]

As is apparent from the above description,
According to the present invention, a burner plate having a mixing passage for the fuel and the spraying medium is provided at the tip of a burner plug for distributing and supplying the spraying medium such as fuel and steam. The burner plate has a mixing passage introduced from the mixing passage. In a slurry fuel burner provided with a burner tip formed with a mixing chamber for receiving fuel and formed with an injection hole for mixed fuel, a passage axis of a mixing passage for introducing mixed fuel into the mixing chamber is provided inside the mixing chamber. While crossing, the position of the intersection is set so that the distance between the intersection and the tip surface of the burner chip is between 0.5 and 0.8 with respect to the axial length inside the burner chip, In addition, since the burner chip and the burner plate are each made of the same ceramic material, the mixed fuel injected from the plurality of mixing passages collide in the mixing chamber. Dispersed in an equal, yet sufficient mixing is performed. In addition, the velocity of collision of the mixed fuel injected from the mixing chamber with the inner surface of the burner chip is reduced, and the fuel is sufficiently mixed in the burner chip. Density bias is reduced. Furthermore, according to the present invention, since the slurry flowing along the inner wall of the burner chip is sufficiently sheared to form a thin film, generation of coarse particles during spraying is prevented. Further, since different materials are not attached to the burner chip or the burner plate or screwed and used, cracks of ceramics due to differences in thermal deformation do not occur and the life of the burner is greatly extended.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a slurry fuel burner according to an embodiment.

FIG. 2 is an explanatory diagram showing a mixed state of a mixed fuel in a burner chip of the burner.

FIG. 3 is a longitudinal sectional view of a conventional burner for slurry fuel.

FIG. 4 is a longitudinal sectional view of another conventional slurry fuel burner.

[Explanation of symbols]

 Reference Signs List 1 burner plug 2 fuel supply hole 3 spray medium supply hole 4 burner plate 5 fuel distribution chamber 5a guide hole 6 first mixing chamber 7 burner chip 8 second mixing chamber 9 injection hole 10 tip nut 12b sleeve

Claims (1)

(57) [Claims] A burner plate having a mixing passage for the fuel and the spraying medium is provided at the tip of a burner plug for distributing and supplying a spraying medium such as fuel and vapor. The burner plate is introduced into the burner plate from the mixing passage. In a slurry fuel burner provided with a burner tip that forms a mixing chamber for receiving the mixed fuel and forms an injection hole for the mixed fuel,
The passage axis of the mixing passage for introducing the mixed fuel into the mixing chamber is crossed inside the mixing chamber , and the position of the intersection is determined.
The distance between the intersection and the tip of the burner tip is the burner tip.
0.5 to 0.8 for the axial length inside the chip
A burner for a slurry fuel, wherein the burner tip and the burner plate are set to be between them, and the burner chip and the burner plate are each made of the same material ceramics. "