JP3897664B2 - Structure to prevent excessive deformation of refractory material structures - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a structure for preventing excessive deformation of a refractory material structure such as a cyclone of a circulating fluidized bed boiler.
[0002]
[Prior art]
Conventionally, a circulating fluidized bed boiler (CFB) has been widely used as a combustion or combustion boiler for coal, dewatered sludge, municipal waste, and the like. Such a circulating fluidized bed boiler is provided with a cyclone for separating combustion gas and fluidized sand at the outlet side of a fluidized bed furnace (combustor) equipped with a fluidized bed heat exchanger (boiler) and the like. It functions as an incineration or combustion boiler for municipal waste or the like while returning to the fluidized bed heat exchanger or fluidized bed furnace through a seal pot or the like.
[0003]
As shown in FIG. 5, the cyclone supports a plurality of plate-like refractory materials 103 between adjacent refractory materials 103 by supporting the inner wall of the casing 100 with a heat insulating material 101 and anchors 102. It is constructed as a so-called refractory material structure with a joint 104 attached thereto.
[0004]
[Problems to be solved by the invention]
However, in the conventional cyclone (refractory material structure) as described above, fluid sand and the like separated from the combustion gas penetrate into the joint 104 during the high temperature operation of the circulating fluidized bed boiler, and this gradually increases. If deposited, the thermal elongation of the refractory material 103 cannot be absorbed, and eventually the cyclone will be excessively deformed or the supporting steel will be excessively bent due to exceeding the allowable value of the expansion section installed in the lower part of the cyclone. There was a problem that such damage occurred.
[0005]
Therefore, an object of the present invention is to provide a structure for preventing excessive deformation of a refractory material structure that can prevent excessive deformation of the refractory material structure with a simple structure.
[0006]
[Means for Solving the Problems]
In order to solve the above-described problems, the structure for preventing excessive deformation of a refractory material structure according to the present invention has a structure in which a large number of plate-like refractory materials are heated between adjacent refractory materials by supporting the inner wall of the casing with a heat insulator and anchors. In the refractory material structure attached with a joint for absorbing elongation , a horizontal joint portion of the joint is constructed obliquely downward as a structure for preventing excessive deformation due to thermal elongation of the refractory material.
[0007]
Further, in the refractory material structure in which a large number of plate-like refractory materials are attached to the inner wall of the casing via an insulating material and anchored, and joints for absorbing thermal elongation are arranged between adjacent refractory materials, As an over-deformation preventing structure due to thermal elongation, the anchor is installed obliquely with respect to the thermal elongation direction of the refractory material .
[0010]
The refractory material structure is a cyclone of a circulating fluidized bed boiler.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the structure for preventing excessive deformation of a refractory material structure according to the present invention will be described in detail with reference to the accompanying drawings.
[0012]
[First embodiment]
FIG. 1 is a schematic configuration diagram of a circulating fluidized bed boiler showing a first embodiment of the present invention, and FIG. 2 is an enlarged sectional view of a portion A (cyclone inner wall) of FIG.
[0013]
As shown in FIG. 1, in a circulating fluidized bed boiler, a fluidized bed furnace (combustor) 2 provided with a fluidized bed heat exchanger 1 for exchanging heat with boiler water introduces primary air from below, such as silica sand. After the fluidized sand and the combusted material are fluidly mixed to perform primary combustion, secondary air is introduced into the freeboard portion 2a above it to perform secondary combustion, thereby completing the combustion of the combustible gas.
[0014]
Then, the combustion gas heated at high temperature by the combustion is led to the cyclone 3 together with the fluidized sand, and after being separated into the combustion gas and the fluidized sand by the cyclone 3, the combustion gas is guided to the rear smoke channel 4. After heat exchange is performed on the primary air and the secondary air introduced into the fluidized bed furnace (combustor) 2 in the rear heat exchanger 5, fly ash and the like are removed through a bag filter (not shown) and then not shown. Released into the atmosphere by a chimney or the like. On the other hand, the fluid sand separated by the cyclone 3 is directly returned to the fluidized bed furnace (combustor) 2 via the hot recycling pipe 7a by the seal pot 6 and the fluidized bed heat exchanger 1 via the cold recycling pipe 7b. Distribution control is performed on what is returned.
[0015]
As shown in FIG. 2, the cyclone 3 is supported by a stainless steel anchor 12 through a heat insulating material 11 made of glass fiber or the like on the inner wall of a steel plate casing 10 and a large number of plate-like refractory materials 13 made of ceramics or the like. Is constructed as a so-called refractory material structure in which joints 14 for absorbing thermal elongation are disposed between refractory materials 13 adjacent to each other.
[0016]
And as a structure for preventing excessive deformation due to thermal expansion of the refractory material 13, a horizontal joint portion of the joint 14 is constructed obliquely downward.
[0017]
Therefore, even when fluid sand or the like separated from the combustion gas in the cyclone 3 enters the joint 14 during high-temperature operation of the circulating fluidized bed boiler, it is difficult to accumulate due to falling due to vibration or the like. The thermal elongation can be absorbed well over a long period of time. As a result, the cyclone 3 is excessively deformed or the supporting steel frame is excessively large, for example, when the thermal elongation of the refractory material 13 exceeds the allowable value of an expansion portion (not shown) installed in the lower part of the cyclone 3 as in the prior art. No damaging damage occurs.
[0018]
[Second Embodiment]
FIG. 3 is a cross-sectional view of a cyclone inner wall portion showing a second embodiment of the present invention.
[0019]
This is a structure for preventing excessive deformation due to thermal elongation of the refractory material 13, such as welding the anchor 12 in the first embodiment obliquely upward with respect to the direction of thermal elongation of the refractory material 13 (see the arrow in the figure) to the casing 10. This is an example.
[0020]
According to this, the rigidity of the anchor 12 is increased, the downward thermal extension of the refractory material 13 is suppressed, and the same effect as in the first embodiment can be obtained.
[0021]
[Third embodiment]
FIG. 4 is a cross-sectional view of a cyclone inner wall portion showing a third embodiment of the present invention.
[0022]
This is an example in which a non-deformable portion 11a is partially provided in the heat insulating material 11 in the first embodiment as a structure for preventing excessive deformation due to thermal expansion of the refractory material 13. As the non-deformed portion 11a, a hard heat insulating material 11 may be used, or a ring-shaped metal plate may be used.
[0023]
According to this, the mounting strength of the heat insulating material 11 is increased and the downward thermal extension of the refractory material 13 is suppressed, and the same effect as in the first embodiment can be obtained.
[0024]
Needless to say, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the present invention. For example, the excessive deformation preventing structure of the present invention may be applied not only to the inner wall of the cyclone but also to the inner walls of the seal pot 6, the hot recycling pipe 7a, and the cold recycling pipe 7b. Moreover, this invention is applicable not only to a circulating fluidized bed boiler but to refractory material structures, such as another installation.
[0025]
【The invention's effect】
As described above in detail with reference to the embodiments, according to the invention of claim 1, a large number of plate-like refractory materials are heated between adjacent refractory materials by supporting the inner wall of the casing via a heat insulating material and anchors. In the refractory material structure that has been bonded with stretch absorbing joints, the horizontal joints of the joints were constructed diagonally downward as a structure to prevent excessive deformation due to thermal expansion of the refractory materials. Excessive deformation of the refractory material structure can be prevented. Further, even if fluid sand or the like enters the joint, it is difficult to deposit due to falling due to vibration or the like, and the thermal elongation of the refractory material can be absorbed well over a long period of time.
[0026]
According to the invention of claim 2, a refractory material in which a large number of plate-like refractory materials are attached to the inner wall of the casing via the heat insulating material and anchored with joints for absorbing thermal elongation between adjacent refractory materials. In the structure, as the structure for preventing excessive deformation due to the thermal elongation of the refractory material, the anchor is installed obliquely with respect to the direction of thermal expansion of the refractory material, so that the refractory structure has an excessive deformation with a simple structure. Can be prevented. Moreover, the downward thermal extension of a refractory material is suppressed.
[0029]
According to the invention of claim 3 , since the refractory material structure is a cyclone of a circulating fluidized bed boiler, the casing effectively absorbs the thermal elongation of the refractory material at a high temperature of about 850 ° C. with respect to about 60 ° C. Or it can be suppressed and effective.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a circulating fluidized bed boiler showing a first embodiment of the present invention.
FIG. 2 is an enlarged cross-sectional view of a portion A (cyclone inner wall portion) of FIG.
FIG. 3 is a sectional view of a cyclone inner wall portion showing a second embodiment of the present invention.
FIG. 4 is a sectional view of an inner wall portion of a cyclone showing a third embodiment of the present invention.
FIG. 5 is a cross-sectional view of a conventional cyclone inner wall.
[Explanation of symbols]
1 Fluidized bed heat exchanger 2 Fluidized bed furnace (combustor)
3 Cyclone 4 Rear smoke 5 Rear heat exchanger 6 Seal pot 10 Casing 11 Heat insulating material 12 Anchor 13 Refractory material 14 Joint

Claims (3)

A refractory material structure in which a large number of plate-like refractory materials are attached to an inner wall of a casing through a heat insulating material and anchored, and a joint for absorbing thermal elongation is disposed between adjacent refractory materials. A structure for preventing excessive deformation of a refractory material structure , wherein a horizontal joint portion is constructed obliquely downward in the joint as a structure for preventing excessive deformation due to elongation. A refractory material structure in which a large number of plate-like refractory materials are attached to an inner wall of a casing through a heat insulating material and anchored, and a joint for absorbing thermal elongation is disposed between adjacent refractory materials. A structure for preventing excessive deformation of a refractory material structure, wherein the anchor is installed obliquely with respect to the heat expansion direction of the refractory material as a structure for preventing excessive deformation due to elongation . Excessive deformation preventing structure of the refractory structure, according to claim 1 or 2 refractory structure as claimed is characterized in that a cyclone of a circulating fluidized bed boiler.

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