JP6653186B2 - Refractory structures - Google Patents

Description

  The present disclosure relates to refractory structures.

  Conventionally, in equipment equipped with a high-temperature treatment device such as an incinerator, a boiler, and a melting furnace, a refractory structure in which a refractory material is arranged via a heat insulating material inside a casing forming an outermost wall is often used. I have. This is because the casing is thermally protected by lining a refractory material in a furnace, a cyclone, or a site where a high-temperature fluid such as various pipes comes into contact. Generally, the refractory material is supported by a plurality of support members attached to the casing by welding or the like, for example, a Y anchor.

  Here, in the above-described fire-resistant structure, a stress acts on the support member in the axial direction of the support member due to a difference in thermal expansion between the casing and the refractory material, and the support member may be damaged. Therefore, the refractory material supporting member disclosed in Patent Document 1 has a displacement absorbing portion. The displacement absorbing portion is capable of absorbing a stress acting on the support member in the axial direction of the support member due to a difference in the amount of thermal expansion between the casing and the refractory material. Thereby, the breakage of the refractory material support member is prevented.

JP 2009-180420A

Even if the refractory material supporting member disclosed in Patent Literature 1 is adopted, the difference in thermal expansion between the casing and the refractory material still remains. In order to more reliably prevent the breakage of the support member, it is desirable to reduce the difference in thermal expansion between the casing and the refractory material.
In addition, when there is a difference in the amount of thermal elongation, the refractory material may be cracked or lifted up from the support member, and the refractory material may fall off depending on the position. From this point as well, it is desirable to reduce the difference in the thermal expansion between the casing and the refractory material.

  In view of the above circumstances, an object of at least one embodiment of the present invention is to reduce the difference in the amount of thermal elongation between a refractory material layer and a casing as compared with the related art, and prevent peeling of the refractory material layer and breakage of the support member. An object of the present invention is to provide a refractory structure.

(1) The refractory structure according to at least one embodiment of the present invention includes:
A casing,
A plurality of support members extending from the inner surface of the casing toward the inside of the casing,
A refractory material layer disposed inside the casing, wherein the refractory material layer defines a flow path supported by the casing via the support member and through which a fluid of 500 ° C. or higher can flow.
A heat insulating material layer disposed between the casing and the refractory material layer,
A heat insulating material layer covering an outer surface of the casing.

  According to the above configuration (1), since the heat insulating material layer covers the outer surface of the casing, the temperature of the casing can be increased when the refractory structure is used, as compared with the case where the outer surface of the casing is not covered. . As a result, the amount of thermal expansion of the casing increases, and the difference in the amount of thermal expansion between the casing and the refractory material layer can be reduced. As a result, it is possible to reduce the stress acting on the refractory material layer and the support member due to the difference in the thermal elongation between the casing and the refractory material layer, and to prevent the refractory material layer from peeling off and the support member from being broken. it can.

(2) In some embodiments, in the above configuration (1),
In a state where the fluid having a temperature of 500 ° C. or more and 950 ° C. or less flows through the flow path, a difference in thermal elongation between the casing and the refractory material layer is 1.4 mm or less per 1 m. .
According to the above configuration (2), the difference in the amount of thermal elongation between the casing and the refractory material layer is 1.4 mm or less per meter in a state where the fluid is flowing through the flow path. The stress acting on the layer and the support member can be reduced. As a result, according to the above configuration (2), it is possible to prevent the refractory material layer from falling off and the support member from being broken.

(3) In some embodiments, in the above configuration (1) or (2),
In a state where the fluid having a temperature of 500 ° C. or more and 950 ° C. or less flows through the flow path, the temperature of the casing is configured to be in a range of 300 ° C. or more and 400 ° C. or less.
According to the above configuration (3), the temperature of the casing is in a range of 300 ° C. or more and 400 ° C. or less in a state where the fluid is flowing through the flow path, so that the temperature of the casing is, for example, 25 ° C. As a result, the heat elongation of the casing increases. This makes it possible to reduce the difference in thermal expansion between the casing and the refractory material layer.

(4) In some embodiments, in any one of the configurations (1) to (3),
When the thickness of the refractory material layer is t1, the thickness of the heat insulating material layer is t2, and the ratio of the thickness t2 of the heat insulating material layer to the thickness t1 of the refractory material layer is t2 / t1,
The ratio t2 / t1 is in the range of 2 or more and 3.5 or less.
According to the above configuration (4), since the ratio t2 / t1 is in the range of 3.5 or less, the amount of temperature decrease in the heat insulating material layer is suppressed in a state where the fluid is flowing through the flow path. . Thereby, the temperature of the casing can be increased as compared with the case where the ratio t2 / t1 is more than 3.5, and the difference in thermal elongation between the casing and the refractory material layer can be reduced.

(5) In some embodiments, in any one of the above configurations (1) to (4),
The support member has a deformable displacement absorbing portion.
In the above configuration (5), it is possible to absorb the stress acting on the support member in the axial direction of the support member due to the difference in the amount of thermal elongation between the casing and the refractory material layer. And the breakage of the support member are more reliably prevented.
In particular, at the time of a cold start of the equipment to which the refractory structure is applied, the temperature of the refractory material layer rises in a shorter time than the temperature of the casing. The difference in thermal elongation between the refractory material layer and the refractory material layer increases. According to the displacement absorbing portion, even at the time of a cold start, the displacement acting portion can be deformed, thereby absorbing the stress acting on the refractory material layer and the support member. Breakage can be prevented.

(6) In some embodiments, in any one of the configurations (1) to (5),
The refractory structure has a plurality of slits separating the refractory layer into a plurality of sections.
In the above configuration (6), the difference in the amount of thermal elongation between the casing and the refractory material layer can be absorbed by the slit, whereby the peeling of the refractory material layer and the breakage of the support member can be more reliably prevented.
In particular, at the time of a cold start of the equipment to which the refractory structure is applied, the temperature of the refractory material layer rises in a shorter time than the temperature of the casing. The difference in thermal elongation between the refractory material layer and the refractory material layer increases. According to the slit, even at the time of a cold start, it is possible to absorb the thermal expansion amount of the refractory material layer, and as a result, it is possible to absorb the stress acting on the refractory material layer and the support member, and Peeling and breakage of the support member can be prevented.

(7) In some embodiments, in any one of the above configurations (1) to (6),
The refractory structure is a cyclone applied to a circulating fluidized bed boiler,
The fluid includes liquid sand.
In a cyclone applied to a circulating fluidized bed boiler, the fluid contains hot combustion gases and fluidized sand. For this reason, the wall surface constituting the flow path is easily worn by the fluidized sand. In this regard, according to the above configuration (7), since the refractory material layer that partitions the flow path has wear resistance, even if the fluid contains flowing sand, the wall surface that forms the flow path is worn. Is prevented.

  According to at least one embodiment of the present invention, there is provided a fire-resistant structure in which the difference in the amount of thermal elongation between the fire-resistant material layer and the casing is reduced as compared with the related art, and peeling of the fire-resistant material layer and breakage of the support member can be prevented. You.

It is a figure showing the schematic structure of the circulating fluidized-bed boiler to which the cyclone as a fireproof structure concerning one embodiment of the present invention was applied. It is sectional drawing of the area | region II in FIG. 1, Comprising: It is a partial sectional view which shows roughly the structure of the wall of a cyclone. It is a graph which shows roughly the temperature distribution (temperature gradient) at the time of operation of a circulating fluidized-bed boiler in the thickness direction of the wall of a cyclone concerning an embodiment of the present invention. It is sectional drawing corresponding to FIG. 2 of the wall of the cyclone concerning another embodiment. It is sectional drawing corresponding to FIG. 2 of the wall of the cyclone concerning another embodiment.

Hereinafter, some embodiments of the present invention will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in the embodiments or shown in the drawings are not intended to limit the scope of the present invention thereto, but are merely illustrative examples. Absent.
For example, expressions representing relative or absolute arrangement such as “in a certain direction”, “along a certain direction”, “parallel”, “orthogonal”, “center”, “concentric” or “coaxial” are strictly described. Not only does such an arrangement be shown, but also a state of being relatively displaced by an angle or distance that allows the same function to be obtained.
For example, expressions such as "identical", "equal", and "homogeneous", which indicate that things are in the same state, not only represent exactly the same state, but also have a tolerance or a difference to the extent that the same function is obtained. An existing state shall also be represented.
For example, an expression representing a shape such as a square shape or a cylindrical shape not only represents a shape such as a square shape or a cylindrical shape in a strict sense geometrically, but also a concave protrusion or a chamfer within a range where the same effect can be obtained. A shape including a part and the like is also represented.
On the other hand, the expression “comprising”, “comprising”, “including”, “including”, or “having” one component is not an exclusive expression excluding the existence of another component.

FIG. 1 shows a schematic configuration of a circulating fluidized bed boiler 1 to which a cyclone 4 as a refractory structure according to an embodiment of the present invention is applied.
As illustrated in FIG. 1, the circulating fluidized bed boiler 1 includes a fluidized bed furnace 2, a cyclone 4, a seal pot 6, and an external heat exchanger 8.

The fluidized-bed furnace 2 is supplied with primary air from below, as well as fluidized sand such as silica sand and combustion products. In the fluidized-bed furnace 2, the combustion material is fluid-mixed with the primary air and the fluidized sand, and is primarily burned. In the fluidized bed furnace 2, secondary air for secondary combustion is supplied to the free board portion 2a located above the primary combustion region, and the combustible gas in the combustion gas generated in the primary combustion is burned. Let me do.
Note that coal, heavy oil, waste, RDF (Refuse Derived Fuel: garbage solid fuel), biomass, or the like can be used as a combustion product.

  The outlet of the fluidized bed furnace 2 is connected to the cyclone 4 via a pipe 10. The cyclone (centrifugal separator) 4 has an inlet to which the pipe 10 is connected at its upper part, and can separate the fluid sent from the fluidized-bed furnace 2 into combustion gas and fluidized sand. The cyclone 4 has an outlet for fluidized sand separated at its lower part, and the outlet for fluidized sand is connected to the seal pot 6 via a pipe 12.

An external heat exchanger 8 is connected to the seal pot 6 via a pipe 14, and the external heat exchanger 8 is connected to a lower part of the fluidized bed furnace 2. The seal pot 6 is connected to a lower part of the fluidized-bed furnace 2 via a pipe 16.
Therefore, the circulating fluidized bed boiler 1 has a fluidized sand circulation path 18 through which the fluidized sand circulates, and the fluidized bed furnace 2, the cyclone 4, the seal pot 6, and the external heat exchanger 8 are inserted into the fluidized sand circulation path 18. Have been.

On the other hand, the circulating fluidized bed boiler 1 has an internal heat exchanger 20, an air preheater 22, a dust collector 24, and a chimney 26.
In particular, the cyclone 4 has, at its top, an outlet for the separated combustion gases. The internal heat exchanger 20, the air preheater 22, the dust collector 24, and the chimney 26 are sequentially connected via a pipe to an outlet for the combustion gas of the cyclone 4.

  Therefore, the circulating fluidized-bed boiler 1 has a combustion gas passage 28 through which the combustion gas flowing out of the cyclone 4 flows, and the internal heat exchange in the combustion gas passage 28 in order from the upstream in the flow direction of the combustion gas. A vessel 20, an air preheater 22, a dust collector 24, and a chimney 26 are sequentially inserted.

  Further, the circulating fluidized-bed boiler 1 has an air supply path 30 for supplying air to the fluidized-bed furnace 2, and an air preheater 22 is inserted in the air supply path 30 upstream of the fluidized-bed furnace 2. Have been.

  In the circulating fluidized-bed boiler 1 having the above configuration, fluidized sand and combustion products are supplied to the fluidized-bed furnace 2, and high-temperature air heated by the air preheater 22 is supplied from the lower portion through the air supply path 30. You. Inside the fluidized-bed furnace 2, high-temperature air, fluidized sand, and combustion products are fluid-mixed and primary combustion is performed. Then, the combustible gas in the combustion gas generated by the primary combustion is secondary-combusted, and a high-temperature combustion gas is generated. The temperature of the high-temperature combustion gas is, for example, 850 ° C.

  The high-temperature combustion gas generated in the fluidized-bed furnace 2 is guided to the cyclone 4 together with the fluidized sand, and is separated into the combustion gas and the fluidized sand by the cyclone 4. When the separated combustion gas is guided to the combustion gas passage 28 and passes through the internal heat exchanger 20, it performs heat exchange with, for example, liquid-phase water. This produces steam from the liquid water.

When the fuel gas passes through the air preheater 22, the combustion gas exchanges heat with the air supplied to the fluidized bed furnace 2. Therefore, the high temperature air heated by the air preheater 22 is supplied to the fluidized bed furnace 2.
In the dust collector 24, fly ash and the like are removed from the combustion gas, and the combustion gas is purified. The purified combustion gas is discharged to the atmosphere by a chimney 26, while the high-temperature fluidized sand separated by the cyclone 4 is directly returned to the fluidized-bed furnace 2 by the seal pot 6 and the external heat exchanger 8. To be supplied to The temperature of the hot fluidized sand is, for example, 850 ° C.

FIG. 2 is a cross-sectional view of a region II in FIG. 1, and is a partial cross-sectional view schematically illustrating a configuration of a wall 32 a of the cyclone 4. FIG. 3 is a graph schematically showing a temperature distribution (temperature gradient) during the operation of the circulating fluidized bed boiler 1 in the thickness direction of the walls 32a, 32b, 32c of the cyclone 4. FIG. 4 is a sectional view corresponding to FIG. 2 of a wall 32b of a cyclone 4 according to another embodiment. FIG. 5 is a cross-sectional view corresponding to FIG. 2 of a wall 32c of a cyclone 4 according to another embodiment.
In the following description, the walls (fireproof walls) 32a, 32b, and 32c of the cyclone 4 are collectively referred to as a wall 32.

The wall 32 of the cyclone 4 has a casing 34, a plurality of support members 36, a refractory material layer 38, a heat insulating material layer 40, and a heat insulating material layer 42, as shown in FIGS. The cyclone 4 has a cylindrical shape, and the wall 32 of the cyclone 4 also has a cylindrical shape.
The casing 34 is made of, for example, a carbon steel plate having a thickness of 5 mm or more and 15 mm or less. In the case of the cyclone 4, the casing 34 has a cylindrical shape. The casing 34 forms a skeleton of the cyclone 4, and a frame (not shown) for supporting the cyclone 4 supports, for example, an upper portion of the casing 34. In this case, the cyclone 4 is supported in a suspended state.

The support member 36 extends in the thickness direction of the wall 32a from the inner surface of the casing 34 perpendicular to the thickness direction of the wall 32a toward the inside of the casing 34. The support member 36 is made of, for example, stainless steel.
The refractory material layer 38 is arranged inside the casing 34 and is supported by the casing 34 via a support member 36. The refractory material layer 38 defines a flow path 44 through which a fluid at 500 ° C. or higher can flow. In the case of the cyclone 4, a combustion gas containing liquid sand flows through the flow path 44 as a fluid.

  The refractory material layer 38 is made of an irregular refractory. The amorphous refractory contains, for example, alumina and silica as main components, and has heat resistance, abrasion resistance, and corrosion resistance. For example, amorphous refractories have a maximum service temperature of 1300 ° C. or more and 1700 ° C. or less. In particular, the refractory material layer 38 has higher wear resistance than the heat insulating material layer 40. The application of the amorphous refractory is carried out, for example, by kneading the raw material of the amorphous refractory, pouring it into a mold, and then heating and curing the raw material of the amorphous refractory.

  The heat insulating material layer 40 is disposed between the casing 34 and the refractory material layer 38. The heat insulating material layer 40 contains, for example, alumina and silica as main components. The material constituting the heat insulating material layer 40 has a maximum use temperature of, for example, 800 ° C. or more and 1100 ° C. or less, and has heat insulation and heat resistance. In particular, the heat insulating material layer 40 has a lower thermal conductivity than the refractory material layer 38 and a lower bulk specific gravity than the refractory material layer 38. The application of the heat insulating material layer 40 can be performed by, for example, spraying or troweling the raw material of the heat insulating material layer.

The heat insulating material layer 42 covers the outer surface of the casing 34 orthogonal to the thickness direction of the wall 32a. The heat insulating material layer 42 contains, for example, silica as a main component. The heat insulating material layer 42 has a lower thermal conductivity than the heat insulating material layer 40 and is made of, for example, a fibrous heat insulating material such as rock wool or glass wool.
In addition, the wall 32 may further have a cover 46 as needed to hold or protect the heat insulating material layer 42. The cover 46 is made of, for example, a corrugated galvanized steel plate, and is supported by the casing 34 via a locking member 47 made of a metal rod or the like welded to the casing 34.

According to the wall 32 of the cyclone 4 having the above-described configuration, the heat insulating material layer 42 covers the outer surface of the casing 34. Therefore, compared with the case where the outer surface of the casing 34 is not covered, when the cyclone 4 is used, that is, at 500 ° C. The temperature of the casing 34 can be increased in a state where the fluid is flowing through the flow path 44 (steady state). Thereby, the amount of thermal expansion of the casing 34 increases, and the difference in the amount of thermal expansion between the casing 34 and the refractory material layer 38 can be reduced. As a result, the stress acting on the refractory material layer 38 and the support member 36 due to the difference in the amount of thermal elongation can be reduced, and the refractory material layer 38 can be prevented from falling off and the support member 36 can be prevented from being broken.
It is assumed that the difference in the thermal expansion between the casing 34 and the refractory material layer 38 is zero at the temperature (for example, 25 ° C.) when the circulating fluidized bed boiler 1 is stopped.

  In some embodiments, in a state where a fluid having a temperature of 500 ° C. or more and 950 ° C. or less flows through the flow path 44 (steady state), a difference in thermal elongation between the casing 34 and the refractory material layer 38 is 1. It is configured to be 4 mm or less.

  According to the wall 32 of the cyclone 4 having the above-described configuration, the difference in thermal expansion between the casing 34 and the refractory material layer 38 is 1.4 mm or less per 1 m in a state where the fluid is flowing through the flow path 44. The stress acting on the refractory material layer 38 and the support member 36 can be reduced. As a result, according to the above configuration, it is possible to prevent the refractory material layer 38 from peeling off and the support member 36 from being broken.

When the temperature distribution in the thickness direction of the wall 32 is as shown in FIG. 3, the thermal expansion ΔL1 of the refractory material layer 38 and the thermal expansion ΔL2 of the casing 34 are expressed by the following equations (1), respectively. , (2).
ΔL1 = α1 × (T1 + T2) / 2 (1)
ΔL2 = α2 × T3 (2)
In Equation (1), α1 represents the coefficient of linear expansion of the refractory material layer 38, T1 represents the temperature of the inner surface of the refractory material layer 38, and T2 represents the temperature of the outer surface of the refractory material layer 38. In Equation (2), α2 represents the coefficient of linear expansion of the casing 34, and T3 represents the temperature of the casing 34.

Therefore, when the difference in the amount of thermal elongation between the casing 34 and the refractory material layer 38 is ΔL0, ΔL0 can be expressed by the following equation (3).
ΔL0 = ΔL1-ΔL2 (3)
Therefore, taking into account the equations (1), (2) and (3), the coefficient of linear expansion α1 of the refractory layer 38, the temperature T1 of the inner surface of the refractory layer 38, the temperature T2 of the outer surface of the refractory layer 38, the casing By adjusting at least one of the linear expansion coefficient α2 of the casing 34 and the temperature T3 of the casing 34, the difference ΔL0 in the amount of thermal elongation between the casing 34 and the refractory material layer 38 becomes 1 per m. 0.4 mm or less.
However, in general, since the temperature T1 of the inner surface of the refractory material layer 38 is determined by the temperature of the fluid flowing through the flow path 44, the difference ΔL0 in the thermal expansion amount is set to be equal to or less than 1.4 mm per 1 m. To do so, at least one of the temperature T2 of the outer surface of the refractory material layer 38, the coefficient of linear expansion α2 of the casing 34, and the temperature T3 of the casing 34 is adjusted.

On the other hand, when the heat moving on the wall 32 is Q, the heat Q can be expressed by the following equation (4).
Q = λ1 / t1 × ΔT1 = λ2 / t2 × ΔT2 = λ3 / t3 × ΔT3 (4)
In equation (4), λ1 is the thermal conductivity of the refractory material layer 38, t1 is the thickness of the refractory material layer 38, λ2 is the thermal conductivity of the heat insulating material layer 40, t2 is the thickness of the heat insulating material layer 40, λ3 Represents the thermal conductivity of the heat insulating material layer 42, and t3 represents the thickness of the heat insulating material layer 42, respectively. As shown in FIG. 3, ΔT1, ΔT2, and ΔT3 represent T1-T2, T2-T3, and T3-T4, respectively, where T1 is the temperature of the inner surface of the refractory material layer 38, and T2 is The temperature of the outer surface of the refractory material layer 38 or the inner surface of the heat insulating material layer 40, T3 is the temperature of the outer surface of the heat insulating material layer 40 or the inner surface of the heat insulating material layer 42 (temperature of the casing 34), and T4 is the temperature of the outer surface of the heat insulating material layer 42. Represents temperature.

  Therefore, when adjusting any one or more of the temperature T1 of the inner surface of the refractory material layer 38, the temperature T2 of the outer surface of the refractory material layer 38, and the temperature T3 of the casing 34, as shown in Expression (4). The thermal conductivity λ1 of the refractory material layer 38, the thickness t1 of the refractory material layer 38, the thermal conductivity λ2 of the heat insulating material layer 40, the thickness t2 of the heat insulating material layer 40, the heat conductivity λ3 of the heat insulating material layer 42, In addition, at least one of the thickness t3 of the heat insulating material layer 42 may be adjusted.

  In some embodiments, the wall 32 has a thermal expansion between the casing 34 and the refractory layer 38 in a state where a fluid having a temperature of 700 ° C. or more and 950 ° C. or less flows through the flow path 44 (steady state). Is set to be 1.4 mm or less per 1 m.

In some embodiments, the temperature of the casing 34 is configured to be in a range of 300 ° C. to 400 ° C. in a state where a fluid having a temperature of 500 ° C. to 950 ° C. is flowing through the flow path 44 (steady state). ing.
According to the wall 32 of the cyclone 4 having the above configuration, when the cyclone 4 is used, the temperature of the casing 34 falls within the range of 300 ° C. or more and 400 ° C. or less while the fluid is flowing through the flow path 44. Is greater than, for example, 25 ° C., the thermal expansion ΔL2 of the casing 34 increases. Thereby, the difference ΔL0 in the thermal elongation between the casing 34 and the refractory material layer 38 can be reduced.
On the other hand, the temperature of the casing 34 is 400 ° C. or lower, which is sufficiently lower than the fluid flowing through the flow path 44. For this reason, even if thermal stress repeatedly acts on the casing 34, the number of repetitions (fatigue life) until the casing 34 is damaged can be sufficiently increased, and the durability of the casing 34 is ensured.

  In some embodiments, the temperature of the casing 34 falls within the range of 300 ° C. or more and 400 ° C. or less in a state where a fluid having a temperature of 700 ° C. or more and 950 ° C. or less flows through the flow path 44 (steady state). It is configured as follows.

In some embodiments, as shown in FIG. 3, the thickness of the refractory layer 38 is t1, the thickness of the insulation layer 40 is t2, and the thickness of the insulation layer 40 relative to the thickness t1 of the refractory layer 38. Assuming that the ratio of the thickness t2 is t2 / t1, the ratio t2 / t1 is in the range of 2 or more and 3.5 or less.
According to the wall 32 of the cyclone 4 having the above configuration, the ratio t2 / t1 falls within the range of 3.5 or less. The amount of temperature decrease in the layer 40 is suppressed. Thereby, the temperature of the casing 34 can be increased as compared with the case where the ratio t2 / t1 is more than 3.5, and the difference ΔL0 in the amount of thermal elongation between the casing 34 and the refractory material layer 38 is reduced. can do.

In some embodiments, as shown in FIGS. 2 and 4, the support member 36 is constituted by a Y anchor 48 having a Y shape. The Y anchor 48 has a shaft portion 48a and a V-shaped expanding portion 48b connected to the shaft portion 48a. The shaft portion 48a extends in the heat insulating material layer 40, one end of the shaft portion 48a is fixed to the inner surface of the casing 34 by welding, and an expanded portion 48b connected to the other end of the shaft portion 48a is embedded in the refractory material layer 38. Is done. Note that the shaft portion 48a and the expanding portion 48b may be formed integrally, or may be mechanically connected to each other.
According to the Y anchor 48, the refractory material layer 38 can be reliably supported with a simple configuration.

In some embodiments, as shown in FIG. 5, the support member 36 has a deformable displacement absorbing portion 50. The displacement absorbing portion 50 can absorb the stress acting on the support member 36 in the axial direction due to the difference ΔL0 in the thermal expansion amount between the casing 34 and the refractory material layer 38. Breakage of the support member 36 is more reliably prevented.
In particular, when the circulating fluidized-bed boiler 1 is cold started, the temperature of the refractory material layer 38 rises in a shorter time than the temperature of the casing 34. The difference ΔL0 in the amount of thermal elongation with the layer 38 increases. According to the displacement absorbing section 50, even at the time of a cold start, the deformation acting on the displacement absorbing section 50 can absorb the stress acting on the refractory material layer 38 and the support member 36. Peeling and breakage of the support member 36 can be prevented.
In addition, the heat insulating material layer 40 has flexibility that allows the deformation of the displacement absorbing portion 50.

In some embodiments, as shown in FIG. 5, the support member 36 having the displacement absorbing section 50 is configured by a deformed Y anchor (deformed Y anchor) 51. The deformed Y anchor 51 has a shaft portion 51a and a V-shaped expanding portion 51b connected to the shaft portion 51a. The shaft portion 51a extends in the heat insulating material layer 40, one end of the shaft portion 51a is fixed to the inner surface of the casing 34 by welding, and an expanded portion 51b connected to the other end of the shaft portion 51a is embedded in the fireproof material layer 38. Is done. Note that the shaft portion 51a and the expanding portion 51b may be formed integrally, or may be mechanically connected to each other.
The displacement absorbing section 50 is constituted by an elastic deformation section 50a formed integrally with the shaft section 51a. For example, the elastic deformation portion 50a is formed by bending the shaft portion 51a. According to this configuration, the displacement absorbing section 50 can be realized with a simple configuration.
In some embodiments, as shown in FIG. 5, the elastic deformation portion 50a has an L shape or a V shape.

In some embodiments, as shown in FIG. 4, the wall 32b has a plurality of slits (joints) 52 separating the refractory layer 38 into a plurality of sections. The plurality of slits 52 are formed in the refractory material layer 38 in, for example, a mesh shape, some of the slits 52 extend in the vertical direction, and some of the slits 52 extend in the horizontal direction.
The slits 52 extending in the vertical direction can absorb the difference in the amount of thermal expansion between the casing 34 and the refractory layer 38 in the circumferential or horizontal direction, and the slits 52 extending in the horizontal direction The difference in the amount of thermal expansion between the casing 34 and the refractory material layer 38 can be absorbed. Therefore, according to the above configuration, the difference in the amount of thermal elongation between the casing 34 and the refractory material layer 38 is small, and the difference in the amount of thermal elongation can be absorbed by the slits 52. Breakage of the member 36 is more reliably prevented.

  In particular, when the circulating fluidized bed boiler 1 is cold started, the temperature of the refractory material layer 38 rises in a shorter time than the temperature of the casing 34. The difference ΔL0 in the amount of thermal elongation with the layer 38 increases. According to the slit 52, even at the time of a cold start, the amount of thermal elongation of the refractory material layer 38 can be absorbed, and as a result, the stress acting on the refractory material layer 38 and the support member 36 can be absorbed, It is possible to prevent the refractory material layer 38 from falling off and the support member 36 from being broken.

  Note that the vertical direction described in FIGS. 2, 4, and 5 means a vertical direction. Generally, the cyclone 4 is arranged such that its axis coincides with the vertical direction, so that the radial direction of the cyclone 4 coincides with the horizontal direction. The circumferential direction of the cyclone 4 extends in the horizontal direction while curving so as to surround the axis of the cyclone 4 in a horizontal plane. The wall 32 shown in FIGS. 2, 4 and 5 is a part of the peripheral wall of the cyclone 4, and the thickness direction of the wall 32 matches the horizontal direction.

  In some embodiments, a backup material (protection member) 54 is embedded in a region of the heat insulating material layer 40 that is located on an extension of the slit 52 in the thickness direction of the wall 32. The backup material 54 is made of, for example, a standard refractory material such as a refractory brick. By arranging the backup material 54 in the region of the heat insulating material layer 40 located on the extension of the slit 52, even if the slit 52 is provided, the heat insulating material layer 40 can be protected from the fluid.

In some embodiments, the temperature of the cover 46 is configured to be in a range of 40 ° C. to 60 ° C. while the fluid having a temperature of 500 ° C. to 950 ° C. is flowing through the flow path 44.
In the above configuration, the temperature of the cover 46 is in a range of 40 ° C. or more and 60 ° C. or less in a state where the fluid is flowing through the flow path 44. Since the temperature of the cover 46 is 40 ° C. or more and 60 ° C. or less, safety of a worker working around the cyclone 4 is ensured.

  In the embodiment described above, the cyclone 4 applied to the circulating fluidized-bed boiler 1 has been described as an example of the refractory structure according to the present invention. In the cyclone 4, the fluid flowing through the flow path 44 contains hot combustion gas and fluidized sand. For this reason, the wall surface constituting the flow path 44 is easily worn by the fluidized sand. In this regard, according to the above configuration, the refractory material layer 38 defining the flow path 44 has wear resistance, so that even if the fluid contains flowing sand, the wear of the wall surface forming the flow path 44 is reduced. Is prevented.

The present invention is not limited to the above-described embodiment, and includes a form in which the above-described embodiment is modified and a form in which these forms are combined.
For example, the refractory structure according to the present invention can be applied to other than the cyclone 4, and can also be applied to the seal pot 6 and the pipes 10, 12, 14, and 16. Further, the refractory structure according to the present invention can be applied to equipment other than the circulating fluidized-bed boiler 1, and can be applied to equipment provided with a high-temperature treatment device such as an incinerator or a melting furnace. Therefore, the fluid flowing through the flow path 44 is not limited to the combustion gas or the fluidized sand.
Further, for example, in the wall 32b shown in FIG. 4, the slit 52 penetrates the refractory material layer 38 and reaches the heat insulating material layer 40, but the slit 52 does not have to penetrate the refractory material layer 38. . In this case, the backup material 54 can be omitted.

DESCRIPTION OF SYMBOLS 1 Circulating fluidized-bed boiler 2 Circulating fluidized-bed furnace 2a Free board part 4 Cyclone 6 Seal pot 8 External heat exchanger 10, 12, 14, 16 Pipe 18 Fluid sand circulation path 20 Internal heat exchanger 22 Air preheater 24 Dust collector 26 Chimney 28 combustion gas passage 30 air supply passages 32, 32a, 32b, 32c wall (fireproof wall)
34 casing 36 support member 38 refractory material layer 40 heat insulating material layer 42 heat insulating material layer 44 flow path 46 cover 47 locking member 48 Y anchor 48a shaft portion 48b expanding portion 50 displacement absorbing portion 50a elastic deformation portion 51 deformed Y anchor 51a shaft Part 51b Expanding part 52 Slit 54 Backup material

Claims (7)

A casing,
A plurality of support members extending from the inner surface of the casing toward the inside of the casing,
A refractory material layer disposed inside the casing, wherein the refractory material layer defines a flow path supported by the casing via the support member and through which a fluid of 500 ° C. or higher can flow.
A heat insulating material layer disposed between the casing and the refractory material layer,
And a heat insulating material layer covering an outer surface of the casing. In a state where the fluid having a temperature of 500 ° C. or more and 950 ° C. or less is flowing through the flow path, a difference in thermal elongation between the casing and the refractory material layer is set to fall within a range of 1.4 mm or less per m. The refractory structure according to claim 1, wherein: 2. The temperature of the casing is in a range of 300 ° C. to 400 ° C. in a state where the fluid having a temperature of 500 ° C. or more and 950 ° C. or less flows through the flow path. Or the refractory structure according to 2. When the thickness of the refractory material layer is t1, the thickness of the heat insulating material layer is t2, and the ratio of the thickness t2 of the heat insulating material layer to the thickness t1 of the refractory material layer is t2 / t1,
The refractory structure according to any one of claims 1 to 3, wherein the ratio t2 / t1 is in a range of 2 or more and 3.5 or less. The refractory structure according to any one of claims 1 to 4, wherein the support member has a deformable displacement absorbing portion. The refractory structure according to any one of claims 1 to 5, comprising a plurality of slits for separating the refractory material layer into a plurality of sections. The refractory structure is a cyclone applied to a circulating fluidized bed boiler,
The refractory structure according to any one of claims 1 to 6, wherein the fluid includes fluid sand.

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