JP3684126B2 - Refractory structure of the furnace body - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a refractory structure of a furnace body that is incinerated or melted.
[0002]
[Prior art]
Conventionally, Al ₂ O ₃ · SiO ₂ refractory materials are generally used for linings of blast furnaces, converters, and combustion furnaces and combustion melting furnaces used for processing industrial waste.
[0003]
Taking a combustion melting furnace as an example to treat industrial waste, the combustion melting furnace introduces combustible gas, char, and ash generated in the preceding stage, for example, a pyrolysis gasification furnace, and has a high temperature of 1200 ° C or higher, for example. Combustion takes place and the ash is melted and recovered as slag. At this time, the molten slag contacts the refractory material constructing the inner wall of the furnace and erodes its surface.
[0004]
The mechanism of erosion by molten slag is that the oxides CaO, SiO ₂ , Al ₂ O ₃ , MgO, etc., which are the main components of slag, are almost the same as the components of the refractory material. It is thought that the mutual diffusion of refractory material constituent ions and slag constituent element ions becomes active due to the temperature difference, and as a result, erosion proceeds. When the refractory material is significantly eroded, it is necessary to replace the refractory material, thereby shortening the life of the furnace body.
[0005]
Therefore, the applicant of the present application has previously filed a refractory member that is not easily corroded and eroded even in an environment in contact with a highly erodible molten slag and can extend the life of the furnace body (Japanese Patent Laid-Open No. 3-158434). Issue gazette).
[0006]
The refractory member described in the publication is composed of a refractory material and a refractory metal plate joined to the surface thereof, and the portion where the molten slag contacts in a high temperature and corrosive atmosphere is made of chromium alone or a chromium alloy. The refractory metal plate has been arranged to protect the surface of the refractory material and succeeded in extending the life of the furnace body.
[0007]
[Problems to be solved by the invention]
Chromium adopted as the refractory metal plate is suitable for protecting a refractory material in a corrosive atmosphere because it has high strength and high corrosion resistance. However, since the toughness is poor and welding cannot be performed, the workability is inferior. Therefore, when joining the refractory metal plate and the refractory material, ribs having a relatively simple trapezoidal cross section are formed on the back surface of the refractory metal plate as anchors, while the convex portion is formed on the refractory material side. A groove is formed in correspondence with the rib, and the refractory metal plate is fixed to the refractory material by fitting the protrusion and the groove.
[0008]
However, the above-described joint structure between the refractory metal plate and the refractory material has a problem that the anchor effect is low because the protruding ribs do not extend deeply into the refractory brick. Further, if the ridge rib is formed by cutting, there is a problem that the machining allowance on both sides of the ridge rib is increased, which is not economical.
[0009]
The present invention has been made in view of the problems in the conventional refractory structure as described above, and provides a refractory structure for a furnace body having a low anchoring effect and a high anchor effect.
[0010]
[Means for Solving the Problems]
According to the first aspect of the present invention, there is provided a refractory structure of a furnace body in which an inner wall is made of a refractory material, and a refractory metal plate is attached to at least a portion of the inner wall that is in contact with a high-temperature substance. An anchor connection part having a thread part for attaching the anchor metal fitting to the metal plate is provided, and the anchor metal part is fixed to the refractory metal plate by being screwed to the anchor connection part. It is the refractory structure of the furnace body which is comprised in the shape which can connect a refractory metal plate and a refractory material so that they cannot be peeled by being embedded in the refractory material.
[0011]
According to the second aspect of the present invention, there is provided a furnace body in which the anchor connecting portion is formed of a refractory metal boss screwed to the refractory metal plate, and the boss is provided with a screw portion for screwing the anchor metal fitting to the boss. Refractory structure.
[0012]
The present invention of claim 3 is a refractory structure of a furnace body in which the refractory metal plate is made of chromium alone or a chromium alloy.
[0013]
The present invention of claim 4 is a refractory structure of a furnace body in which the anchor metal fitting is composed of a metal member having a lower heat resistant temperature than the refractory metal plate.
[0014]
The present invention of claim 5 is a refractory structure of a furnace body in which the anchor portion is constituted by a rod-shaped member having a bent portion.
[0015]
The present invention of claim 6 is a refractory structure of a furnace body in which the anchor portion is constituted by a combination of a rod-like member and a plate-like member.
[0016]
In the present invention, as a specific example of the above refractory material, for example, a conventionally known refractory material formed into a fan shape or a slender shape mainly composed of SiO ₂ , Al ₂ O ₃ , Fe ₂ O ₃ , Ca0 or the like is shown. It is. On the other hand, as a specific example of the refractory metal plate, chromium alone or a chromium alloy (a chromium alone containing, for example, one or more of W, Mo, Nb, Ta, and V) is shown. When a refractory metal plate is composed of chromium alone or a chromium alloy, the refractory metal plate self-generates a film in a high-temperature atmosphere, and the film directly contacts the high-temperature material, specifically, molten slag and the refractory material. Therefore, the erosion of the furnace wall can be remarkably reduced.
[0017]
Further, the predetermined depth at which the anchor fitting is extended is at least 1/2 or more of the heat insulation thickness of the refractory material.
[0018]
According to the first aspect of the present invention, since the anchor metal fitting extended from the refractory metal plate is configured as a separate part from the refractory metal plate, there is a degree of freedom in making the shape to enhance the anchor effect, and the refractory metal Since it comprised so that it might fix with screws with respect to a board, a refractory metal plate can be reliably joined to a refractory material, improving the anchor effect. Thereby, even if the refractory structure of the present invention is applied to the vertical inner wall surface of the furnace body, there is no possibility that the refractory metal plate is peeled off.
[0019]
When the anchor metal fitting is directly screwed to the refractory metal plate and the tip of the threaded portion of the anchor metal fitting is exposed from the inner surface of the refractory metal plate, there is a possibility that a high-temperature substance may contact the screw portion and cause the anchor metal to be melted. . Therefore, according to the second aspect of the present invention, since the anchor fitting is fixed to the refractory metal plate via the refractory metal boss, the anchor fitting can be prevented from being melted.
[0020]
According to the third aspect of the present invention, since the refractory metal plate is composed of chromium alone or a chromium alloy, erosion of the refractory material can be prevented while enhancing the anchor effect.
[0021]
According to the fourth aspect of the present invention, if the anchor metal fitting is made of a metal member having a lower heat resistance temperature than the refractory metal plate, for example, stainless steel, thermal deformation of the anchor metal fitting is prevented while obtaining an effect of enhancing the anchor effect. be able to.
[0022]
According to the present invention of claim 5, the bent portion of the rod-shaped member acts to enhance the anchor effect.
[0023]
According to the present invention of claim 6, the plate-like member attached via the rod-like member acts so as to enhance the anchor effect.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail based on the embodiments shown in the drawings.
[0025]
FIG. 1 shows an overall configuration of a combustion melting furnace to which a refractory structure of a furnace body according to the present invention is applied and a waste treatment facility including the combustion melting furnace.
[0026]
In the figure, waste as waste is temporarily stored in a waste pit 1 and is put into a hopper 1b by a crane 1a. Garbage discharged from the hopper 1b is introduced into the crusher 1c and finely crushed, and then sent to the dust feeder 2 via the garbage conveyor 1d. The dust feeder 2 serves as a pyrolysis gasification furnace. The fluidized bed furnace 3 is charged.
[0027]
In the fluidized bed furnace 3, partial combustion is performed under conditions of an air ratio of 0.2 to 0.4, and low temperature pyrolysis is performed with the sand layer temperature maintained at 500 to 600 ° C. All of the waste that has been thrown in, other than the non-combustible material extracted from the bottom of the hearth, is led to the combustion melting furnace 4 that is directly connected (downstream) to the fluidized bed furnace 3.
[0028]
On the other hand, the non-combustible material extracted from the bottom of the hearth is separated into non-combustible material, non-ferrous metal, iron, and fluidized sand through the screw conveyor 5 and the vibrating screen 6 and a magnetic separator (not shown). The fluidized sand is returned to the sand layer of the fluidized bed furnace 3 and reused.
[0029]
The pyrolysis gas containing ash generated in the fluidized bed furnace 3 is guided to the combustion melting furnace 4 and further combusted under the condition of a total air ratio of 1.3. In the combustion melting furnace 4, high-temperature combustion at 1200 ° C. or higher is performed, and the ash is melted and separated as slag, and harmful substances in gas such as dioxin are decomposed. 7 is a slag discharge device, and 8 is a slag drainage conveying device for cooling and solidifying the slag.
[0030]
The melting furnace exhaust gas discharged from the combustion melting furnace 4 is heat-recovered by the waste heat boiler 10, then the temperature is further lowered in the gas cooling chamber 11, and dust is removed by the bag filter 12. The purified exhaust gas then passes through the induction fan 13, passes through the denitration device 14, and is discharged from the chimney 15.
[0031]
In the combustion melting furnace 4, the pyrolysis gas flows tangentially into the primary combustion region 4 a and burns while swirling, and ash is collected on the wall surface to be melted into slag. Next, the combustion gas that has passed through the throttle 4b collides with the bottom surface 4c of the slag separation part, and fine ash that could not be captured is collected and converted into slag. The slag is discharged from the outlet 4d.
[0032]
FIG. 2 is an enlarged view of a portion B in FIG. 1 and shows an enlarged vertical wall portion in the combustion melting furnace 4.
[0033]
In the figure, the furnace wall structure in the vertical wall portion is composed of an outer wall 40, a refractory castable 41a formed along the outer wall 40, and a plurality of refractories 42 stacked in multiple layers inside the refractory castable 41a. It is configured. In the present embodiment, the refractory 42 is disposed over a range in which the furnace wall temperature is high and the slag load is high and the refractory material is easily damaged by the furnace wall, and the refractory castable 41b is provided for the other furnace walls. It has only a configuration.
[0034]
Reference numeral 43 denotes a flange, and a refractory receptacle 44 is provided on the flange 43. On the other hand, a notch 42a is formed in the outer corner of the refractory 42 in the lowermost stage, and the refractory 42 laminated in a state of being engaged with the refractory receiver 44 is supported on the flange 43. ing.
[0035]
Each refractory 42 has a refractory material 45 and a refractory metal plate 46 joined to the front surface thereof, and the configuration thereof is shown in FIG.
[0036]
3A is a plan view of the refractory 42, and FIG. 3B is a front view. As shown in FIG. 3A, the refractory material 45 is formed into a spear shape. When the refractory material 45 is thermally expanded by combustion in the furnace in a combined state, a wedge effect is generated in the direction of the core, and each refractory material 45 is formed. The two are brought into close contact with each other. The refractory material 45 is mainly composed of, for example, SiO ₂ , Al ₂ O ₃ , Fe ₂ O ₃ , Ca0, or the like. In addition, mortar is applied to the joining surfaces of the refractory materials 45 as necessary.
[0037]
On the other hand, the refractory metal plate 46 is made of chromium alone or a chromium alloy (for example, chromium alone containing one or more of W, Mo, Nb, Ta, and V) and exposed in a high-temperature atmosphere. When this occurs, the film self-generates on the surface, and the film functions to avoid direct contact between the refractory material and the molten slag.
[0038]
A boss 47 made of the same material as the refractory metal plate 46 is screwed to the rear surface of the refractory metal plate 46, and an anchor fitting 48 is further screwed to the boss 47.
[0039]
4 to 6 are parts diagrams of the anchor metal fitting 48, the boss 47, and the refractory metal plate 46, respectively.
[0040]
First, in FIG. 4, (a) is a plan view of the anchor fitting 48, and (b) is a right side view thereof. In both figures, the anchor fitting 48 is formed in a Y-shaped rod-shaped member (a rod-shaped member having a bent portion), and two branch portions 48b branched from the base portion 48a are deeply embedded in the refractory material 45. It becomes an anchor part. The extension length of the anchor portion embedded in the refractory material 45 is preferably at least 1/2 or more of the heat insulation thickness of the refractory material 45. The Y-shaped bar-shaped member constitutes a shape that can connect the refractory metal plate 46 and the refractory material 45 in a non-peelable manner.
[0041]
The base portion 48 a is formed with a male screw portion 48 c, and the male screw portion 48 c is screwed into the boss 47. As this anchor metal fitting, it is preferable to use stainless steel having high workability and high heat resistance temperature. Although it is conceivable that the anchor metal fitting is made of a chromium alloy used for the refractory metal plate 46, the chromium alloy is brittle, so that the strength is insufficient as an anchor.
[0042]
FIG. 5A is a front view of the boss 47 as an anchor connection portion, and FIG. 5B is a right side view thereof. In both figures, a boss 47 is formed with a female screw portion 47a in which the male screw portion 48c is screwed at the center thereof, and a male screw portion 47b is projected from the front surface of the boss 47 on the same axis as the female screw portion 47a. Further, as shown in FIG. 5B, a part of the peripheral surface of the boss 47 is formed with a notch 47c that is linearly cut in parallel, and this notch 47c is formed of a refractory material. The boss 47 embedded in 45 serves to restrict rotation (in the direction of arrow D) or loosening relative to the refractory metal plate 46.
[0043]
6A is a front view of the refractory metal plate 46, and FIG. 6B is a right side view thereof. In both figures, the refractory metal plate 46 is made of a rectangular member, and a female screw portion 46a into which the male screw portion 47b of the boss 47 is screwed is formed at the center thereof.
[0044]
Thus, according to the configuration in which the anchor metal fitting 48 is not screwed directly to the refractory metal plate 46 but is screwed to the refractory metal plate 46 via the boss 47 made of refractory metal, the refractory metal plate 46 and the anchor metal fitting 48 Since a thermal gradient is generated between the male screw portion 48c and the anchor metal fitting 48 is not made of a refractory metal, a metal member having a high heat resistance temperature can sufficiently withstand heat conduction from the inside of the furnace.
[0045]
And if it is not necessary to use a member with low toughness like a refractory metal, it will become possible to process the anchor metal fitting 48 in a desired shape, and can thereby enhance an anchor effect.
[0046]
FIG. 7 shows a configuration in which the refractory 42 having the above configuration is applied to the portion C shown in FIG. 1, that is, the inclined wall portion. The figure (a) is a top view (EE sectional drawing of FIG.7 (b)), (b) is a front view.
[0047]
In both figures, the furnace wall structure in the inclined wall portion includes an outer wall 50, a heat insulating board 51 formed in two layers along the outer wall 50, a heat insulating castable 52 formed along the heat insulating board 51, and A refractory castable 53 is formed along the heat-insulating castable 52, and a refractory 42 is attached in place of the refractory castable 53 particularly in a portion where the molten slag comes into contact.
[0048]
The refractory 42 is arranged in an annular shape as shown in FIG. 7A and is laminated over a predetermined height (five levels in the present embodiment) as shown in FIG. 7B. Thereby, the cylindrical body comprised with many refractory metal plates 46 is formed in the furnace body wall.
[0049]
FIG. 8 shows a modification of the anchor fitting. FIG. 9A shows the anchor 60a of the anchor fitting 60 formed in a T-shape (a rod-shaped member having a bent portion). FIG. 14B shows the anchor 61a of the anchor fitting 61 having a W-shape. (Bar-shaped member having a bent portion) is bent, and FIG. 8C is composed of a combination of a rod-shaped member and a plate-shaped member, and a flat plate 62a is welded as an anchor portion of the anchor fitting 62. It is. Reference numerals 60b, 61b, and 62b are male screw portions that are screwed into the boss 47.
[0050]
The shape of the anchor metal fitting is not limited to that shown in the above embodiment, and any shape can be used as long as it can be firmly fixed in the refractory material 45 and can prevent the refractory metal plate 46 from being peeled off from the refractory material 45. Can be used.
[0051]
Moreover, although the refractory of this invention was comprised by what was shape | molded in the top shape in the said embodiment, not only this but a fan shape may be sufficient.
[0052]
In addition, the refractory structure of the present invention is applied only to a portion where the molten slag as a high temperature material is in direct contact, but not limited to this, the purpose of extending the life of the furnace body also in a portion where the high temperature material is not in direct contact. Can be applied.
[0053]
Moreover, the refractory structure of the furnace body of the present invention can be applied not only to the above-described combustion melting furnace for industrial waste treatment but also to a blast furnace, a converter, etc. of an ironworks.
[0054]
【The invention's effect】
As is apparent from the above description, according to the present invention of claim 1, the anchor metal fitting is formed of a separate part from the refractory metal plate and has a shape with a high anchor effect, and is fixed to the refractory metal plate with screws. Since it comprised so that an anchor effect may be heightened, a refractory metal plate and a refractory material can be joined reliably.
[0055]
Therefore, even if the refractory structure of the present invention is applied to the vertical inner wall surface of the furnace body, the refractory metal plate can be prevented from peeling off.
[0056]
According to the second aspect of the present invention, since the anchor fitting is fixed to the refractory metal plate via the refractory metal boss, the anchor fitting can be prevented from being melted.
[0057]
According to this invention of Claim 3, since the refractory metal plate was comprised with the chromium single-piece | unit or the chromium alloy, erosion of a refractory material can be prevented, improving an anchor effect.
[0058]
According to the fourth aspect of the present invention, the anchor fitting is made of a metal member having a lower heat resistance temperature than the refractory metal plate, for example, stainless steel, thereby preventing the anchor fitting from being thermally deformed while obtaining the effect of enhancing the anchor effect. can do.
[0059]
According to this invention of Claim 5, the bending part of a rod-shaped member has an effect which improves an anchor effect.
[0060]
According to this invention of Claim 6, the plate-shaped member attached via the rod-shaped member has an effect which improves an anchor effect.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a configuration of a waste treatment facility provided with a combustion melting furnace having a refractory structure according to the present invention.
FIG. 2 is an explanatory view showing a refractory structure applied to a vertical wall of a combustion melting furnace.
FIG. 3A is a plan view showing a configuration of a refractory, and FIG. 3B is a front view.
4A is a front view showing the configuration of an anchor fitting, and FIG. 4B is a right side view thereof.
5A is a front view showing a configuration of a boss portion, and FIG. 5B is a right side view thereof.
6A is a front view showing a configuration of a refractory metal plate, and FIG. 6B is a right side view thereof.
7A is a plan sectional view showing a configuration of a vertical wall of a combustion melting furnace, and FIG. 7B is a front sectional view.
FIGS. 8A, 8B, and 8C are perspective views showing other embodiments of anchor fittings.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Garbage pit 2 Dust feeder 3 Fluidized bed furnace 4 Combustion melting furnace 40 Outer wall 42 Refractory material 45 Refractory material 46 Refractory metal plate 47 Boss 48 Anchor metal fittings

Claims (6)

In a refractory structure of a furnace body in which an inner wall is made of a refractory material and a refractory metal plate is attached to at least a portion of the inner wall that is in contact with a high-temperature substance, an anchor fitting is attached to the refractory metal plate to the refractory metal plate. An anchor connection portion having a screw portion for mounting is provided, and the anchor metal part is fixed to the refractory metal plate by being screwed to the anchor connection part. A refractory structure for a furnace body, characterized in that the refractory metal plate and the refractory material can be connected in a non-peelable manner by being embedded in the material. 2. The furnace body according to claim 1, wherein the anchor connection portion is formed of a refractory metal boss screwed to the refractory metal plate, and a screw portion for screwing the anchor metal fitting to the boss is provided. Refractory structure. The refractory structure of a furnace body according to claim 1 or 2, wherein the refractory metal plate is made of chromium alone or a chromium alloy. The refractory structure of the furnace body in any one of Claims 1-3 in which the said anchor metal fitting is comprised from the metal member whose heat-resistant temperature is lower than a refractory metal plate. The refractory structure of the furnace body in any one of Claims 1-4 in which the said anchor part is comprised from the rod-shaped member which has a bending part. The refractory structure of the furnace body in any one of Claims 1-4 in which the said anchor part is comprised from the combination of a rod-shaped member and a plate-shaped member.

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