Burner

Abstract

This invention provides a burner with a reduced overall weight and less positional deviation.　Provided is a burner (1) for supplying a fuel (F) to a kiln (cement kiln 2), the burner being suspended from above the kiln (2). It is preferable that the total length of the burner (1) is no more than 1000 mm, and the total length is accommodated in a mantle (kiln front mantle 3) of the kiln (2). It is preferable that the burner (1) can move in the axial direction, the height direction, and the left-right direction, and the angle of the axis thereof with respect to the horizontal plane can be adjusted.

Description

Burner

[0001] The present invention relates to a burner for supplying fuel to a kiln, such as solid powder fuel, gaseous fuel, or liquid fuel.

[0002] In order to perform heating with good thermal efficiency in response to changes in the type of material to be treated, the blending ratio, the treatment volume, the discharge temperature, etc., a kiln and its operating method have been proposed in which the burner is suspended by a mounting device and can be moved by a manual handle, and the tip of the burner flame can be directed over the entire cross-section of the kiln furnace body (see Patent Document 1).

[0003] Japanese Patent Application Publication No. 2003-4383

[0004] While the burners mentioned above are effective, because they are inserted into the kiln from the side, they are long in length and cantilevered. Consequently, they are prone to misalignment over long periods of operation, potentially resulting in inefficient heating. For example, if the burner is facing downward, the burner flame may strike the product, causing a deterioration in quality, destabilizing the kiln's operation, or even damaging the inner wall bricks. Therefore, the burner position must be adjusted each time, but moving a long, heavy burner is not easy, and the work requires a lot of manpower.

[0005] SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-mentioned problems with conventional burners, and has as its object to provide a burner that is lightweight and less likely to shift out of position.

[0006] To achieve the above object, the present invention provides a burner for supplying fuel to a kiln, which is suspended from above the kiln.

[0007] According to the present invention, by suspending the burner from above, the overall length of the burner can be significantly shortened compared to conventional methods, and the burner can be made lighter. In addition, since the fuel can be transported by dropping it onto the burner from above, the amount of primary air required for transporting the fuel can be reduced, and the amount of nitrogen oxides emitted from the firing device and the amount of fuel used can also be reduced.

[0008] The overall length of the burner is set to 1000 mm or less so that it can be accommodated within the mantle of the kiln, thereby enabling further weight reduction.

[0009] Furthermore, by making the burner movable in the axial direction, height direction and left-right direction of the burner and by making the angle of the axis relative to the horizontal plane adjustable, the position of the burner can be easily adjusted.

[0010] As described above, according to the present invention, it is possible to provide a burner that is lightweight and less likely to shift position.

[0011] 1 is a diagram showing a first embodiment of a burner according to the present invention, in which (a) is a front view and (b) is a vertical cross-sectional view. FIG. 2 is a schematic diagram for explaining an example of installation of the burner shown in FIG. 1. FIG. 3 is a diagram showing a second embodiment of a burner according to the present invention, in which (a) is a front view and (b) is a vertical cross-sectional view.

[0012] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described in detail with reference to the drawings. In the following description, a case where a burner according to the present invention is used in a cement kiln will be exemplified.

[0013] 1 shows a first embodiment of a burner according to the present invention, with the burner 1 comprising a main body 1a and a solid powdered fuel flow passage 1c, and configured so that solid powdered fuel (hereinafter referred to as "fuel") F such as pulverized coal is ejected from a tip 1e. A large diameter portion 1d is formed on the outer circumferential surface of the burner 1, excluding the tip 1e side, and acts to direct secondary air A2 from a clinker cooler 13 (see FIG. 2) toward the burner 1. The cross section of the solid powdered fuel flow passage 1c is not limited to a ring shape and can have other shapes.

[0014] As shown in Figure 2, the burner 1 is suspended from above the cement kiln 2. By adopting a suspended type, the overall length of the burner 1 can be significantly shortened compared to conventional burners. In addition, by keeping the overall length of the burner 1 to 1000 mm or less so that it can fit inside the kiln mantle 3, further weight reduction is possible.

[0015] Above the kiln front mantle 3, rails 4, a movable part 6 that can move on the rails 4 via wheels 7, and a support part 5 are provided, and the burner 1 is supported so that it can move in the axial direction of the cement kiln 2 (the axial direction of the burner 1). In addition, pressure bolts 18 and 19 are provided on the support part 5 so that the burner 1 can be moved in the height direction, and a joint part 17 is provided on the support part 5 so that the angle of the axis of the burner 1 relative to the horizontal plane can be adjusted. Furthermore, although not shown, by making the part below the movable part 6 movable in the left-right direction (direction perpendicular to the plane of the paper in FIG. 2), the burner 1 can also be moved in the left-right direction, making it easy to adjust the position of the burner 1.

[0016] Above the furnace mantle 3, there are arranged a fuel F storage tank 8, a feeder 9, rotary valves 14 and 15, a chute 10, a flexible duct 16, a blower 11, and a conveying pipe 12, and the fuel F in the storage tank 8 is dropped and supplied to the burner 1 by the blower 11. By supplying the fuel F by dropping it, the amount of primary air A1 can be reduced.

[0017] Next, a cement burning method using the burner 1 will be described with reference to FIGS.

[0018] Before operating the cement kiln 2, the position of the burner 1 is adjusted appropriately. As described above, this position adjustment is performed by the movable part 6, the support part 5, the joint part 17, the pressing bolts 18, 19, etc., so that the position of the tip 1e of the burner 1 in the axial direction, height direction, and left-right direction of the burner 1, and the angle of the axis of the burner 1 relative to the horizontal plane, are optimized. In this case, since the burner 1 has been made lighter, it is easier to handle and is less likely to become displaced after installation.

[0019] During cement burning, fuel F is dropped from storage tank 8 through feeder 9, rotary valves 14 and 15, chute 10, and flexible duct 16, and is then supplied to burner 1 by blower 11 via conveying pipe 12. Conveying air from blower 11 becomes primary air A1 and flows through solid powdered fuel flow path 1c. By increasing the ejection speed of the fuel flow, the ejector effect causes secondary air A2 to be drawn in from the outer peripheral surface side of large diameter portion 1d of burner 1, and this air is supplied to cement kiln 2. This enables combustion with high momentum even with a small amount of primary air A1.

[0020] Next, a second embodiment of the burner according to the present invention will be described with reference to FIG. 3. This burner 21, not shown, is similar to the burner 1 described above. It is suspended from above the cement kiln 2, has a total length of 1,000 mm or less, is housed within the kiln mantle 3, and is movable axially, vertically, and laterally, and the angle of its axis relative to the horizontal plane is adjustable. In addition, the burner 21 is a three-channel burner, having a main body 21a equipped with a solid powdered fuel flow passage 21c with a swirl vane at its tip, a first air flow passage 21d positioned on the outside adjacent to the solid powdered fuel flow passage 21c and primarily flowing straight, and a second air flow passage 21e (with a swirl vane at its tip) positioned on the inside adjacent to the solid powdered fuel flow passage 21c and primarily flowing in a swirling manner. The combustibility of the fuel F can be adjusted by independently controlling the airflow of each of the three channels.

[0021] In the above-described embodiment, the burners 1 and 21 according to the present invention are used as burners for cement kilns. However, they can also be used in kilns (continuous kilns, semi-continuous kilns, single kilns, rotary kilns, etc.) constituting all kinds of industrial furnaces, such as firing furnaces, heating furnaces, drying furnaces, and preheating furnaces, other than cement kilns.

[0022] Furthermore, although an example has been given in which solid powder fuel is used as fuel, gaseous fuel or liquid fuel can also be used instead of solid powder fuel, in which case the solid powder fuel flow paths 1c and 21C become gaseous fuel flow paths and liquid fuel flow paths.

[0023] The illustrated embodiments are merely examples and are not intended to limit the technical scope of the present invention.

[0024] 1, 21 Burner 2 Cement kiln 3 Furnace front mantle 4 Rail 5 Support part 6 Movable part 7 Wheel 8 Storage tank 9 Feeder 10 Chute 11 Blower 12 Conveying piping 13 Clinker cooler 14, 15 Rotary valve 16 Flexible duct 17 Joint part 18, 19 Push bolt A1 Primary air A2 Secondary air F Fuel

Claims

1. A burner for supplying fuel to a kiln, characterized in that it is suspended above the kiln.

2. A burner as claimed in claim 1, characterized in that the overall length of said burner is less than 1000 mm, and said burner is housed within the mantle of said kiln.

3. A burner as claimed in claim 1 or 2, characterized in that the burner is movable in the axial direction, height direction and left / right direction, and the angle of the axis with respect to the horizontal plane is adjustable.

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