JPH029203Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an air distribution plate for a fluidized bed combustion apparatus.

Conventionally, a fluidized bed combustion apparatus such as a fluidized bed boiler has a main body 1 whose lower part is partitioned with an air dispersion plate 2 as shown in FIG. 4, air is supplied from an air supply pipe 5 provided on the side of the wind box 3, and fuel (coal particles) is supplied from a coal supply pipe provided through the bottom of the furnace body 1 and the air distribution plate 2. It was supplied with air from tube 6. Such fluidized bed combustion equipment enables in-bed desulfurization by using desulfurizing agent particles such as limestone as a medium in the fluidized bed, and when using fuels with high sulfur content such as coal, large-scale exhaust emissions are possible. It has attracted particular attention in recent years because it eliminates the need for smoke desulfurization equipment.

Air dispersion plate (hereinafter referred to as
As shown in FIG. 2, a known dispersion plate is one in which short riser pipes 7A are erected in a large number of holes 7 provided in a flat plate 2. However, in such a dispersion plate 2, the fluidizing air is blown from below only upward through the pipe 7A, so the dispersibility of the fluidized bed medium is poor, and when the operation is stopped, the fluidized medium is blown into the riser pipe 7A. It has the drawback of causing problems such as backflow and blockage.

The object of this invention is to provide an air distribution plate for a fluidized bed combustion apparatus that eliminates the drawbacks of the prior art described above, has good dispersibility of the fluidized medium, and does not cause troubles such as tube clogging of the fluidized medium.

This invention provides an air dispersion plate for a fluidized bed combustion apparatus having a large number of holes in which riser pipes are respectively installed, in which an angle between the tip of the riser pipe and a horizontal plane is equal to or greater than the angle of repose of the fluidized medium, and The present invention is characterized in that the cap has a hole that is inclined downward so that the extension line of the inclination angle is located above the hole in which the adjacent riser pipe is provided.

This invention will be explained in more detail below with reference to the drawings. FIG. 3 is a partial sectional view showing an example of the dispersion plate of this invention. In the figure, a riser pipe 7A is provided in a hole 7 formed in the distribution plate 2, and a cap 8 having a nozzle 9 is provided at the tip of the riser pipe 7A.
are fixed by fillet welds 10. The nozzle 9 is formed in the thick side wall of the cap so as to be inclined downward, and the upper end of the cap is formed into an acute angle so as not to impede the flow of the fluid medium. The angle of inclination between the nozzle 9 and the plane of the nozzle 9 is set to be equal to or greater than the angle of repose of the fluidized medium so that the fluidized medium does not flow backward when the nozzle 9 is stationary, and the extension line of the inclination angle is set to the hole in the dispersion plate where the adjacent riser is provided. It is set to be above the position. According to this embodiment, since the fluidizing air blowing nozzle is provided diagonally downward, the fluidizing air is uniformly blown into the fluidized bed without penetrating upward, and the fluidized bed has sufficiently high mixing properties. This also eliminates the possibility of the flowing medium flowing backwards and clogging the nozzle when the device is stationary. Furthermore, by setting the inclination angle so that the extension line of the above-mentioned inclination angle is above the position of the hole on the distribution plate of the adjacent riser, air is directly distributed to the plane between the holes 7 of the distribution plate 2. Because combustion ash or fluidized medium is deposited in this area,
The surface of the dispersion plate can be thermally protected and its deterioration can be prevented.

Note that if the plane of the dispersion plate 2 up to the adjacent hole 7 intersects with the extension line of the inclination angle of the nozzle, the surface of the dispersion plate 2 will always be exposed to high-temperature blown air, and the dispersion plate will may cause deterioration. As the air for fluidizing the fluidizing medium, in addition to air, a mixed gas of air and combustion exhaust gas, combustion exhaust gas, etc. can also be used.

As described above, according to this invention, it is possible to improve the mixability of the fluidized medium in a fluidized bed combustion apparatus, increase combustion efficiency, desulfurization rate, etc., and also prevent troubles such as nozzle clogging due to backflow of the fluidized medium when the operation is stopped. can do.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing an outline of a fluidized bed combustion device, FIG. 2 is a partial cross-sectional view of a fluidizing air distribution plate used in a conventional fluidized bed combustion device, and FIG.
FIG. 2 is a partial cross-sectional view of an air distribution plate showing an embodiment of this invention. 2...Air distribution plate, 7...Hole, 7A...Rise pipe, 8...Cap, 9...Nozzle.

Claims (1)

[Scope of utility model registration request] In an air dispersion plate for a fluidized bed combustion apparatus having a large number of holes in which riser pipes are respectively installed, the tip of the riser pipe is provided with an inclination angle that is greater than or equal to the angle of repose of the fluidized medium with respect to a horizontal plane, and 1. An air distribution plate for a fluidized bed combustion apparatus, characterized in that a cap is provided with a hole that slopes downward so that the extension line is located above the hole in which an adjacent riser is provided.