JP2955234B2 - Refractory structure for water pipe protection - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refractory structure for protecting a water pipe of a boiler such as a waste heat recovery boiler utilizing waste heat from a waste incinerator, and particularly to a municipal solid waste and industrial waste. The present invention relates to a refractory structure used as a refractory tube block structure for a plant that incinerates and obtains steam energy of a boiler by the heat of the combustion exhaust gas.

[0002]

2. Description of the Related Art FIG. 12 shows a conventional structure of a refractory structure for protecting a water pipe of a waste heat recovery boiler for recovering waste heat from a waste incinerator from heat from combustion exhaust gas and corrosive atmosphere. An example is shown.

In FIG. 12, reference numeral 11 denotes a boiler water pipe;
Is a planar rib for connecting and reinforcing the water pipe 11 in a horizontal or vertical direction. Reference numeral 26 denotes a refractory block made of a ceramic material provided so as to cover the water pipe 11 from the combustion gas side.
6 protects against the heat from the combustion exhaust gas and the corrosive atmosphere.

Reference numeral 23a denotes a bolt for fixing the refractory block 26 to the flat rib 13. The bolt 23a is erected from the flat rib 13 so as to pass through the refractory block 26.
By tightening, the refractory block 26 is connected to the water pipe 11.
And fixed to the planar rib 13. Reference numeral 20 denotes a mortar filled in a space formed between the refractory block 26, the water pipe 11, and the flat rib 13.

[0005]

In the refractory structure of the conventional boiler, the refractory block 26 is made of a ceramic material having high heat resistance, and is formed by the water pipe 11, the flat ribs 13, and the refractory block 26. The water pipe 11 is protected from the combustion gas and its corrosive atmosphere which are filled with the mortar 20 to promote the flow of heat in the space.

However, since the conventional refractory block is made of a ceramic material, it has relatively high thermal conductivity. However, only the nut 23b is tightened, and the gas-side surface 26a is substantially flat. As a result, the thickness of the refractory block 26 is inevitably increased, and as a result, the maximum heat flow cannot be achieved by the conventional technology. Maximum heat flow is important for boiler efficiency. In addition, since the heat transfer from the refractory block 26 to the water pipe 11 is not performed effectively, the temperature difference between the inside and outside of the refractory block 26 increases, and the temperature of the gas side surface 26a increases. As a result, the difference in thermal expansion between the water pipe 11 side (heat-resistant metal material) and the refractory block (ceramics) increases, and as a result, the thermal stress of the refractory block 26 increases.

Further, when the heat transfer between the refractory tube block 16 assembly and the water tube 11 is less than the optimum condition,
The temperature of the outer surface of the refractory block 26 rises, and ash (ash) 24 of the burning fuel residue adheres by melting and forms a heat insulating layer. When the ash begins to adhere, the heat transfer of this layer becomes extremely insufficient, so that the ash 24 is further melt-adhered, and the thickness of the insulating layer is increased, which is a major obstacle to heat transfer. Since the ash 24 contains corrosive components such as chlorine, high-temperature corrosion occurs in the water pipe 11 and damages the water pipe.

Further, since the refractory block 26 is fixed to the flat rib 13 and is fixed to the water pipe 11 of the boiler and the flat rib 13 via an erect bolt 23a, the bolt 23a is tightened. And water pipes 1
One side (heat-resistant metal material) and fire-resistant block (ceramics)
A thermal strain may be generated due to a difference in thermal expansion between the refractory blocks 26, and the refractory block 26 may be damaged by a thermal stress due to a temperature difference between the inside and outside of the refractory block 26. Further, the bolt 2
Since 3a and nut 23b are exposed in the combustion gas, they are easily corroded by the combustion gas, and if such corrosion proceeds, the refractory block 26 may be damaged or fall off.

In view of the above-mentioned problems, the present invention reduces the thermal stress without increasing the thickness of the refractory block, improves the durability by preventing the high-temperature corrosion of the mounting member, and improves the durability. It is an object of the present invention to provide a refractory structure having heat transfer efficiency. Another object of the present invention is to provide a refractory structure which does not cause cracking and breakage of a conventional refractory block, lowering of conduction efficiency due to thickening of mortar, and high-temperature corrosion of fixing means for fixing. With the goal.

[0010]

The first aspect of the present invention mainly corresponds to the embodiment shown in FIGS. 1 to 7. In order to protect the water pipe side of the boiler from the combustion products of the boiler, the first invention is connected to the water pipe side. In a boiler water tube protection refractory structure having a refractory block interposed between the combustion gas side, an inner side faces the water tube side, and is formed so as to substantially cover the water tube side from the combustion gas side, A refractory block provided with a water tube wrapping portion having a side facing the outer peripheral surface of the water pipe formed in an arc shape, and fixing means for removably fixing the two to the side facing the refractory block and the side of the water pipe. The fixing means is a fixing means formed by a concave portion on the refractory block side and a convex portion on the water pipe side, the fixing means being engaged and fixed by fitting the concave and convex portion, and the concave portion on the refractory block side, Thickness formed thicker than wall thickness of water tube envelope Parts formed by recessed (see FIG. 2), the recessed of the thick portion in the water pipe radial cross section,
It is characterized in that the thickness of each of the concave portion on the refractory block side and the water tube covering portion side is substantially equal. The water pipe side does not necessarily mean only the water pipe, but also includes a continuous body of the water pipe and the flat rib, or an aggregate thereof. According to a second aspect of the present invention, as shown in FIGS. 5 to 7, the concave portion of the thick portion according to the first aspect is a tapered concave portion, and the tapered concave portion and the tapered convex portion on the water pipe side. It is specified that the fixing means is a fixing means in which the part is fitted and fixed by loose fitting. That is, as described in more detail, press fitting between the outer peripheral surface of the water pipe and the refractory block with tapered protrusions / recesses is not only easy for installation because of the tapered shape, but also for loose fitting by press fitting. It does not come off because it is fixed. Also, because of the loose fit, the free end side of the refractory block has a degree of freedom that allows thermal expansion, and does not generate excessive thermal stress.

According to a third aspect of the present invention, there is provided a fire-resistant structure for protecting a boiler water pipe in which a fire-resistant block is interposed between the water pipe and the combustion gas in order to protect the water pipe of the boiler from combustion products of the boiler. In the body, the inside faces the water tube side,
A refractory block having a water tube envelope formed so as to substantially hide the water tube side from the combustion gas side and having a side facing the outer surface of the water tube formed in an arc shape; and the refractory block and the water tube side. And a projection (see FIGS. 1 and 4) or an irregular (see FIGS. 5 to 7) fixing means for fixing the both, and at least a part of the fixing means is in direct contact In this state, the water pipe side and the refractory block are fixed in position, and thin mortar is filled between the refractory block other than the direct contact portion and the water pipe.

Further, in claim 4, the fixing means includes:
It specifies that it is a projection which is in contact with the outer peripheral surface of the water pipe on the inner circumference of the water pipe wrapping part of the refractory block. According to this invention, since the protrusion is brought into close contact with the outer peripheral surface of the water pipe, it is possible to prevent the high-temperature corrosive gas from the combustion gas side from intruding into the fixing means, and also to prevent the refractory block and the water pipe from coming into contact with each other. It is possible to make the gap constant and prevent the mortar filling the gap from becoming too thick.

According to this invention, the water tube wrapping portion formed so as to wrap the water tube does not have a substantially box-shaped cross-section on the outer surface side facing the combustion gas as in the prior art, but extends along the surface of the water tube. Because it is formed in an arc shape, it is possible to reduce the thickness of the refractory block, increase in temperature difference between the inner and outer surfaces of the refractory block and heat removal from the water pipe side suppress temperature rise, and reduce thermal stress of the refractory block Is done. In addition, since it has a thin structure having a uniform thickness as described above, it has high heat conductivity, can effectively transmit heat energy to the water pipe, and prevents overheating of the refractory block, as in the conventional case. As a result, ash does not accumulate on the surface on the combustion gas side, and high heat conductivity can be maintained. That is, in the present invention, the conventional refractory block shown in FIG. 12 described above is thick and non-uniform in thickness, so that it is easily cracked by thermal stress. By adopting a refractory block, the above-mentioned drawbacks are eliminated and thermal stress is reduced, and since the block is formed into a semi-circular shape along a thin and uniform water pipe, heat transfer to the water pipe is efficient, and the heat efficiency of the steam generation plant is improved. Increase.

Further, since the fixing means is provided at a position facing the water pipe side without being exposed to the combustion gas side, in other words, it is completely isolated from the combustion gas side and more effective than the water pipe side. Since any heat is removed, there is no problem even if a metal material is used on the water pipe side, and the degree of freedom of the fixing means is increased. Also, it is not a firm tightening and fixing with bolts and nuts like the conventional one, but a mere engagement and fixing,
There is almost no thermal constraint between the water pipe and the refractory block, such as a bolt / nut, and even if there is a shift due to the difference in thermal expansion between the two, it effectively absorbs this and causes thermal strain between the two. Without heat generation, heat damage can of course also be prevented. Further, since there are no bolts, nuts and the like exposed on the combustion gas side as in the conventional case, the occurrence of high-temperature corrosion is suppressed.

[0015]

In the case where the water pipe side is applied to a water pipe having at least two water pipes and a flat rib connecting between adjacent water pipes, a refractory block is formed along the surface shape of the water pipe and the flat rib. The water pipe wrapping portion formed in this way and a planar connecting portion connecting the water pipe wrapping portion, and is provided at a position where the flat rib on the water pipe side and the connecting portion on the fireproof block side face each other. Even when the fixing means is provided by tapered projections / recesses, it is preferable that the tapered projections / recesses are fixed by loose fitting. The reason for this is that by loose fitting, there is a degree of freedom to allow thermal expansion at the fixed position, and no excessive thermal stress is generated.

[0017]

[0018]

Further, in the invention, it is preferable that the refractory block has a plurality of (preferably two) rows of the plurality of water pipe covering portions which are respectively in contact with the water pipes, and that the water pipe has one location. It is preferably mounted via fixing means. Also, the fireproof block is thin and small, and the fireproof block and the water pipe can be engaged with one fixing means, so that the fireproof block can be easily attached and detached, and handling (portability) is also easy. .

The second aspect of the present invention mainly corresponds to the embodiment shown in FIGS. 8 and 9, and the gist is that a large number of small-diameter ceramic tube groups are used in the refractory block. That is, the present invention provides at least one water pipe in a boiler water pipe protection refractory structure in which a refractory block is interposed between the water pipe side and a combustion gas side in order to protect the water pipe side of the boiler from combustion products of the boiler. It is characterized by comprising a refractory block including a number of small-diameter ceramic tubes in direct contact with the outer peripheral surface side, and fixing means for fixing the refractory block to the water pipe side. In this case, the fixing means is configured such that the interdigital ceramic pipe group extends along the flat rib surface of the water pipe and is fixed on the flat rib surface via an anchor made of a high temperature resistant material. Good to do.

According to the invention, since the small-diameter ceramic tube group is formed in the ID shape in the refractory block and used, a thin structure having a uniform thickness is obtained, so that the temperature difference between the inner and outer surfaces of the refractory block and the temperature rise are suppressed. As a result, the thermal stress of the refractory block is reduced and high heat conductivity is brought into direct contact with the water pipe, so that heat energy can be effectively transmitted to the water pipe and overheating of the refractory block is prevented. As in the prior art, ash does not accumulate on the surface on the combustion gas side, and high heat conductivity can be maintained. As a result, also in the present invention, not only the durability of the boiler water pipe and the refractory block is improved, but also the effective energy of the incinerator burning waste is increased. Further, even when deposits such as combustion residues adhere to the refractory block, partial repair can be easily performed by locally removing the interdigitated small tube groups, and maintenance is easy.

The third invention mainly comprises FIGS.
In order to protect the water pipe of the boiler from the combustion products of the boiler, at least in the fireproof structure for boiler water pipe protection in which a fireproof block is interposed between the water pipe and the combustion gas side, A water tube side composed of two water tubes and a planar rib connecting between adjacent water tubes, an arc-shaped water tube envelope formed along the surface shape of the water tube and the planar rib, and the water tube envelope A refractory block composed of a planar connecting portion that connects the covered portions, and fixing means for fixing the planar connecting portion of the refractory block in contact with the planar rib on the water pipe side, Both the water tube covering portion and the planar connecting portion of the refractory block are configured to directly contact the water tube side of the boiler.

According to this invention, since both the water tube covering portion and the planar connecting portion of the refractory block are in direct contact with the water tube side of the boiler, a thin wall structure having a uniform thickness can be obtained. This makes it possible to suppress the increase in temperature difference between the inner and outer surfaces of the refractory block and the temperature rise, thereby reducing the thermal stress of the refractory block and having high heat transfer properties because it comes into direct contact with the water pipe side, which is effective for water pipes. Heat energy can be transferred to the refractory block, overheating of the refractory block is prevented, and ash does not deposit on the surface on the combustion gas side, so that high heat conductivity can be maintained. As a result, the present invention not only improves the durability of the boiler water pipe and the refractory block, but also increases the effective energy of the incinerator that burns waste.

Further, according to the present invention, the refractory block is formed of one semicircular water pipe covering portion (hereinafter, referred to as a semicircular portion) and one flat continuous portion, and the flat continuous portion is free. By fixing the position by engaging the end side with the end face of the semicircular arc portion of the adjacent fireproof block on the other side, it is possible to securely fix the position and minimize the use of bolts and the like. The engagement is shown in FIG.
As shown in (1), the end face of the semicircular portion of the refractory block and the free end side of the planar connecting portion may be engaged and fixed by taper fitting. That is, engaging the refractory blocks with each other by taper fitting not only improves the adhesion between the tube blocks but also reduces the number of bolts.

It is preferable that the fixing means is constituted by screwing means including ceramic bolts arranged on the refractory block side. That is, since the side directly facing the heat flow is formed of ceramic bolts, in other words, since it is a heat-resistant material of the same material as the refractory block, uniform strength can be maintained without a difference in thermal stress.

[0026]

Embodiments of the present invention will be described below with reference to the drawings. However, the dimensions, shapes, relative positions, and the like of the components described in this embodiment are not intended to limit the scope of the present invention, but are merely illustrative examples, unless otherwise specified. Absent. First, an embodiment of the first invention will be described in detail with reference to FIGS. FIG. 1 is a plan sectional view showing a structure of a refractory structure for protecting a water pipe in a waste heat recovery boiler according to an embodiment of the first invention, FIG. 2 is a view taken in the direction of the arrow Z in FIG. 1, and FIG. It is a sectional view taken along the arrow A.

1 to 4, there is shown a sectional configuration of a combustion chamber 1 of a boiler such as a high-temperature incinerator for municipal solid waste and waste. Reference numeral 12 denotes a plurality of rows of water pipes 11 of the boiler and adjacent water pipes 11. This is a water pipe assembly including planar ribs 13 that are connected in a horizontal or vertical direction. Reference numeral 16 denotes a refractory block provided so as to cover the water pipe assembly 12 on one side from the combustion gas side. The refractory block 16 is formed by putting a material having relatively good thermal conductivity, for example, a castable material or the like into a mold. A water tube wrapping portion 16a, which is formed of a molded product or the like and is provided so as to surround one side peripheral surface of the water tube 11 of the boiler, and extends from the water tube wrapping portion 16a along the planar rib 13 on the water tube 11 side. And a planar connecting portion 16b to be provided.

The flat rib 13 of the water pipe 11 of the boiler is provided with an arm portion 18 projecting obliquely upward at a constant pitch along the axial direction (vertical direction). Thick portion 19 corresponding to portion 18
And a recess 1 inside the arm 1 so as to be freely fitted to the arm 18.
The refractory block 16 is firmly engaged with the arm 18 via the mortar 20 by utilizing the gravity, that is, by engaging the arm 17 with a wall-mount type.
It is fixed to one flat rib 13. Therefore, the refractory block 16 has a thick portion 19 opposed to the arm portion 18.
Almost all other parts are formed to be thin with a uniform thickness.

The arm portion 18 and the thick portion 19 and the concave portion 17 of the refractory block 16 corresponding to the arm portion 18 are preferably provided between the water pipes 11 as two sets of the water pipes 11 as a set. Rows or more may be provided as one set. The inner circumference of the water tube covering portion 16a of the refractory block 16 and the water tube 1
The gaps between the outer periphery of the boiler 1 and the inside of the planar connecting portion 16b and the planar ribs 13 of the boiler are filled with a thin mortar 20.

The water tube wrapping portion 1 of the refractory block 16
A flat mountain-shaped projection 21 is formed at the center of the inner periphery of 6a,
A part of the outer periphery of the water pipe 11 is brought into contact with the top of the projection to securely connect the water pipe 11 and the fireproof block 16. Further, at the end of the planar connecting portion 16b of each of the refractory blocks 16, the free ends of the planar portions 16b 'of both the refractory blocks are recessed 16c in a half U-shape to release thermal stress. I have. In this case, the free ends of the plane portions 16b 'of both refractory blocks are separated from each other by a predetermined gap with a predetermined clearance 16d without being recessed in a U-shape as shown in FIG. You may try.

The refractory structure for protecting a water pipe according to the first embodiment includes a refractory block 16 and a flat rib 13 of a boiler water pipe 11.
Are wall-hung engagement between the protruding arm portion 18 and the recessed portion 17, so that there is no need to connect bolts and nuts as in the prior art. For this reason, the water pipe 11 (and the flat rib 1
3) There is no thermal constraint between the side and the refractory block side, and the thermal stress due to this is minimized. Also, the refractory block 16
Has a thin-walled structure with a uniform thickness except for the thick-walled portion 19 in which the concave portion 17 which is a connection portion with the water pipe 11 side is formed, thereby having a high heat transfer property. Thermal energy can be effectively transmitted, and further, thermal stress is reduced by reducing the temperature difference between the inside and the outside of the heat-resistant block 26. Further, the refractory block 16 completely covers the boiler water pipe 11 side from the combustion gas side via the thin mortar 20, and there is no member such as a bolt exposed to the combustion gas side, so that the occurrence of high-temperature corrosion is suppressed. You.

The refractory block 16 is provided with a water pipe 11.
Since one set is provided for each of the two rows, it is thin and compact, easy to handle (carry), attach and detach, and is wall-mounted as described above.
The ease of installation and removal is further superimposed. Further, the operation can be partially performed every two rows of the water pipes 11. Further, since the projections 21 formed on the water pipe wrapping section 16a are closely contacted with the outer circumference of the water pipe 11, high-temperature corrosive gas from the combustion gas side is supplied between the arm section 18 and the concave section 17. Of the mortar 20 can be prevented from intruding into the fixing means, and the mortar 20 can be charged to an appropriate constant thickness by keeping the gap between the refractory block 16 and the water pipe 11 constant.

Further, by adjusting the protrusion (recess amount) of the concave portion 16c provided at the connection end of the refractory block 16, breakage of the refractory block due to thermal expansion can be prevented.

FIGS. 5 to 7 show a second embodiment of the first invention, in which a fixing means is provided with a tapered uneven portion. FIG. 5 shows an embodiment in which adjacent water pipes are connected to each other by plane ribs. As described above, reference numeral 12 denotes a plurality of rows of water pipes 11 of the boiler and the adjacent water pipes 11 connected in a horizontal or vertical direction. This is a water pipe assembly including the flat ribs 13. Reference numeral 56 denotes a refractory block provided so as to cover the water pipe assembly 12 on one side from the combustion gas side. The refractory block 56 is formed by putting a material having relatively good thermal conductivity, for example, a castable material or the like into a mold. A water tube wrapping portion 56a, which is formed of a molded product or the like and is provided so as to surround one side peripheral surface of the water tube 11 of the boiler, and extends from the water tube wrapping portion 56a along the flat rib 13 on the water tube 11 side. The present embodiment is also similar to the above-described embodiment in that it is constituted by a flat continuous portion 56b to be provided.

In this embodiment, in order to form the circular tapered concave hole 50 on the side of the horizontal rib 13 facing the connecting portion 56b in order to mount the refractory block 56, AA is used. As shown in the line sectional view, a ring-shaped tapered guide 58a is protruded, and a tapered recess 58 is formed therein. On the other hand, on the side of the continuous portion 56b of the refractory block 56 facing the flat rib 13 of the water pipe, the periphery thereof is formed in a position corresponding to the tapered concave portion 5 by a tapered circumferential groove 59.
The tapered projection 59 formed by a is projected. Then, the tapered convex portion 59 provided on the refractory block 56 is press-fitted into the tapered concave portion 58 provided on the horizontal rib 13 so that both are loosely fitted. At this time, a small gap is formed between the refractory block 16, the water pipe 11 and the horizontal rib 13, and the mortar 20 fills the gap.

FIGS. 6 and 7 show another embodiment in which each of the water pipes 11 in which adjacent water pipes are continuously connected by plane ribs is extended in parallel. 6 and 7 are different from FIG.
Since the boiler water pipe 11 is surrounded by the combustion gas area all around, the refractory block 66 must be received by the water pipe 11 itself. For this reason, the refractory block 66 is connected to the water pipe 1.
1 is wrapped around the entire circumference and divided into two along the axial direction to form two semicircular water tube wrapping portions 66A and 66B. At the position where the parts 66A, 66B and the outer peripheral surface of the water pipe face each other, a tapered concave portion 68 and a tapered convex portion 69 are provided as fixing means for removably fixing them.
Is provided.

In the present embodiment, the semicircular arc-shaped covering portion 66
A pair of rectangular tapered recessed holes 50 are formed on both the left and right sides of the outer peripheral surface of the water pipe 11 so that the fixing means is located substantially at the center position of the inner peripheral surfaces of A and 66B. That is, as shown in the sectional view taken along the line BB, a square tapered guide 68a is protruded, and a tapered recess 68 is formed therein. On the other hand, the positions corresponding to the tapered recesses 68 of the semicircular arc-shaped covering portions 66A, 66B are made thicker 63 in a rectangular shape, and the periphery of the thicker portion 63 is tapered on the side facing the tapered recessed portion 68. A tapered projection 69 formed by the rectangular groove 69a is provided in a protruding manner.

Of course, the tapered concave portion 68 and the tapered convex portion 69 may be formed in a circular shape, a rectangular shape, or a polygonal shape. Then, the tapered convex portions 59 provided on the semicircular arc-shaped covering portions 66A and 66B are press-fitted into the tapered concave portions 68 of the water pipe 11, so that both are loosely fitted. At this time, the refractory block 16, the water pipe 11, the horizontal rib 1
Since there is a little gap between the three, the mortar 20 fills the gap. Also, the circumferential free end faces and the axial free end faces of the semicircular envelope portions 66A and 66B are preferably opposed to each other with slight clearances 651 and 652. Can prevent the occurrence of thermal strain and thermal damage due to collision.

FIGS. 8 and 9 show the structure of a refractory structure for protecting a water pipe in a waste heat recovery boiler according to an embodiment of the second invention. FIG. 8 is a sectional plan view thereof, and FIG. It is. 8 and 9 show a sectional configuration of a combustion chamber 1 of a boiler such as a high-temperature incinerator for municipal solid waste and waste.
Reference numeral 2 denotes a water tube assembly including a plurality of rows of water tubes 11 of a boiler and planar ribs 13 connecting the water tubes 11 in a horizontal or vertical direction.

A number of small-diameter ceramic tubes 36 are provided so as to cover the water pipe assembly 12 from the combustion gas side.
a refractory block consisting of group a;
“a” is formed by drawing a ceramic material having relatively good thermal conductivity into a tubular shape and firing it. As shown in FIG. 8, the small-diameter ceramic tube 36a is knitted in an interdigitated shape using a heat-resistant steel wire 37, and is configured to be freely bendable in a direction orthogonal to the axis of the small-diameter ceramic tube 36a.

And the above-mentioned interdigital ceramic tube group 3
Numeral 6 is attached to the water pipe assembly 12 so as to cover the entire combustion gas side of the water pipe assembly 12 by directly contacting the assembly. The fixing means is
A heat-resistant steel anchor-3 at a position 362 in contact with the flat rib 13.
5, a part of the small-diameter ceramic tube group 36 is
It is to be fixed to.

According to this embodiment, since the refractory block 36 is formed by using a group of small-diameter ceramic tubes 36a in an interdigital shape, the thickness depends on the diameter of the ceramic tubes 36a, so that a thin wall structure having a uniform thickness is obtained. Also ceramic tube 36
a has a high heat conductivity because it directly contacts the water pipe assembly 12, can effectively transmit heat energy to the water pipe 11, prevents overheating of the refractory block, and causes ash on the surface on the combustion gas side. Without depositing
High heat conductivity can be maintained. Even when deposits such as combustion residues adhere to the refractory block 36, partial repair can be easily performed simply by replacing the attached ceramic tube 36a.

FIG. 10 shows a refractory structure for protecting a water pipe in a waste heat recovery boiler according to one embodiment of the third invention, FIG. 10 (A) is a plan sectional view thereof, and FIG. It is the principal part enlarged view. FIG. 10 shows a sectional configuration of a combustion chamber 1 of a boiler such as a high-temperature incinerator for municipal solid waste or waste, wherein 12 denotes a plurality of rows of water pipes 11 of the boiler and the water pipes 1.
1 is a water tube assembly composed of planar ribs 13 that connect the horizontal and vertical directions 1 to each other.

Reference numeral 46 denotes a refractory block provided so as to cover the water pipe assembly 12 from the combustion gas side. The refractory block 46 is formed by putting a material having relatively good thermal conductivity, for example, a castable material or the like into a mold. Consists of molded products, etc.
A water tube covering portion 461 provided so as to surround one side peripheral surface of the water tube 11 of the boiler, and a water tube 11 from the water tube covering portion 461.
And a flat continuous portion 462 extending along one of the flat ribs 13 on the side. Therefore, the refractory block 46 includes one water pipe covering part 461 and one planar connecting part 462.
And is formed from

These refractory blocks 46 are directly fixed on the planar ribs 13 by ceramic bolts 45 without any mortar layer in order to directly contact the side of the water pipe assembly 12 facing the combustion gas. . In this case, a metal nut 48 is fixed to the flat rib 13 by welding or the like in order to attach the fireproof block 46, while the upper surface side of the flat continuous portion 462 of the fireproof block 46 corresponding to the nut 48 fixing portion is formed into a nut shape. Then, a nut hole 463 a is formed in the recessed portion 463.

As a result, the ceramic bolt 45 is screwed from the combustion gas side using the nut hole 463 a and screwed to the nut 48. Therefore, in this embodiment, the high-temperature corrosion resistance of the ceramic bolt 45 is higher than that of the conventional metal bolt. Even if the nut 48 is made of metal, since the refractory block 46 is concealed by the refractory block 46, there is no excessive rise in temperature due to the combustion gas. The refractory block 46
Engages the flat continuous portion edge 462a with the semicircular portion end surface 461b of the adjacent fireproof block on the other side to fix the position.

In addition, without taking the above-described configuration, as shown in FIG. 11, the end surface 461 of the semicircular portion 461 of the refractory block 46 is used.
c and the end surface 462c of the planar connecting portion 462 may be formed in a tapered shape, and may be engaged by taper fitting. Thereby, compared with the embodiment of FIG. 7, no gap is formed between adjacent refractory blocks, and no high-temperature corrosive substance enters.
Further, the present embodiment has an effect of reducing the number of mounting bolts 15 as compared with FIG. 10, and also can reduce the number of mounting steps.

[0048]

As described above, according to the present invention, there are no bolts and nuts exposed on the combustion gas side, and the occurrence of high-temperature corrosion is suppressed. Further, according to the present invention, mounting and dismounting of the refractory block can be easily performed, and handling (portability) is also facilitated.

Further, since the fixing means can be disengaged without being tightened like a bolt and nut, there is no thermal constraint between the water pipe and the fireproof block, and as a result, the fireproof block can be made thinner. And the temperature difference between the outer surface of the refractory block and the temperature rise is suppressed,
These reduce the thermal stress of the refractory block. In addition, since the refractory block is a refractory block in which the side facing the outer peripheral surface of the water pipe is formed in an arc shape, the portion has a thin-walled structure with a uniform thickness, so that the water pipe has high heat conductivity. Thermal energy can be effectively transmitted, and the refractory block is prevented from being overheated. As a result, ash does not accumulate on the surface on the combustion gas side as in the conventional case, and high heat conductivity can be maintained.

Further, according to the present invention, the high-temperature corrosive gas from the combustion gas side can be effectively prevented from entering the fixing means, the gap between the refractory block and the water pipe is made constant, and the mortar to be charged into the gap is formed. It is also possible to prevent the thickness from becoming excessive.

According to the fifth and sixth aspects of the present invention, the small-diameter ceramic tube group is formed in the refractory block in an interdigital shape, so that the refractory block has a thin-walled structure having a uniform thickness and has a high heat transfer property for directly contacting the water tube. Thus, heat energy can be effectively transmitted to the water pipe. As a result, in the present invention, not only the durability of the boiler water pipe and the refractory block can be improved, but also the effective energy of the incinerator burning waste can be improved.
Increase. Further, even when deposits such as combustion residues adhere to the refractory block, partial repair can be easily performed by locally removing the interdigitated small tube groups, and maintenance is easy.

According to the present invention, since both the water tube covering portion and the planar connecting portion of the refractory block are in direct contact with the water tube side of the boiler, the refractory block has a uniform thickness. As a result, it is possible to improve the durability of the boiler water pipe and the refractory block, as well as to increase the effective energy of the incinerator for burning waste, as in the above-mentioned invention. In particular, the invention described in claim 8 secures the position fixation and uses bolts and the like by engaging the flat continuous portion with the end surface of the semicircular arc portion of the adjacent other-side refractory block to fix the position. Can be kept to a minimum. According to the ninth aspect of the invention, since the side directly facing the heat flow is fixed by the ceramic bolt, uniform strength can be maintained without a difference in thermal stress. According to the tenth aspect of the present invention, since the end faces of the semicircular arc portion and the end face of the flat continuous portion engage the refractory blocks by taper fitting, only the adhesion between the tube blocks is improved. And the number of bolts can be reduced.

[Brief description of the drawings]

FIG. 1 is a radial sectional view of a water pipe protecting refractory structure of a waste heat recovery boiler according to an embodiment of the first invention.

FIG. 2 is a view as viewed in the direction of the arrow Z in FIG. 1 (only essential parts).

FIG. 3 is a sectional view taken along line AA of FIG. 1;

FIG. 4 shows a modification of FIG.

FIG. 5 is a radial sectional view of a water pipe protecting refractory structure according to another embodiment of the first invention.

FIG. 6 is an axial sectional view of a water pipe protecting refractory structure according to still another embodiment of the first invention.

FIG. 7 is a radial cross-sectional view of the water pipe protecting refractory structure of FIG. 6;

8 and 9 show a structure of a refractory structure for protecting a water pipe in a waste heat recovery boiler according to an embodiment of the second invention, and FIG. 5 is a sectional view in a radial direction thereof.

FIG. 9 is an enlarged view of a main part of FIG. 8;

FIG. 10 shows a refractory structure for protecting a water pipe in a waste heat recovery boiler according to an embodiment of the third invention,
(A) is a sectional plan view thereof, and (B) is an enlarged view of a main part thereof.

FIG. 11 is a plan sectional view showing a modification of FIG. 10;

FIG. 12 is a drawing corresponding to FIG. 1 showing a conventional fireproof structure for protecting a water pipe of a boiler.

[Explanation of symbols]

11 water pipe 13 plane rib of water pipe 16, 36, 46, 56, 66 refractory block 16a, 361, 461, 56a, 66A, 66B water pipe wrapping part 16b, 362, 462, 56b planar connecting part 17, 58, 68 Concave portions 18, 59, 69 Convex portions 20 Mortar 21 Projection 36a Small diameter ceramic tube 35 Anchor of high temperature resistant material 45 Ceramic bolt 462c, 461c Taper fitting portion

────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Tetsuro Takahashi 1-8-1, Koura, Kanazawa-ku, Yokohama-shi Mitsubishi Heavy Industries, Ltd. Yokohama Research Laboratory (72) Inventor Chuhachi Goto 1-8-1, Koura, Kanazawa-ku, Yokohama-shi Mitsubishi Yokohama Institute of Heavy Industries, Ltd. (72) Yuzo Kawahara 1-8-1, Koura, Kanazawa-ku, Yokohama-shi Mitsubishi Heavy Industries, Ltd. Yokohama Institute (72) Inventor Minoru Ike 12 Nishikicho, Naka-ku, Yokohama-shi Mitsubishi Heavy Industries, Ltd. (72) Inventor Yasuhiro Terashima 12 Nishikicho, Naka-ku, Yokohama City Inside Mitsubishi Heavy Industries, Ltd.Yokohama Works Ltd. (72) Inventor Keita Inoue 12 Nishikicho, Naka-ku, Yokohama City Mitsubishi Heavy Industries, Ltd.Yokohama Works Ltd. (56) References Hei 1-106706 (JP, U) Actual opening Hei 7-2701 (JP, U) Actual opening Sho 62-156204 (JP, U) Showa 12-5138 (JP, Y1) (58) Field surveyed (Int. Cl. ⁶ , DB name) F22B 37/10 602

Claims (10)

(57) [Claims] 1. A refractory structure for protecting a boiler water pipe in which a refractory block is interposed between the water pipe side and a combustion gas side in order to protect the water pipe side of the boiler from combustion products of the boiler. A refractory block having a water tube envelope formed so as to face the water tube side and substantially hide the water tube side from the combustion gas side, and to have a side facing the water tube outer peripheral surface formed in an arc shape; Fixing means for removably fixing the refractory block and the water pipe on opposite sides thereof , wherein the fixing means comprises a concave part on the refractory block side and a convex part on the water pipe side.
Are formed and engaged and fixed by fitting the concave and convex portions.
And the recess on the refractory block side has a wall thickness on the water tube wrapping part side.
A thicker portion formed to be thicker is formed by recessing, and the recessed portion of the thicker portion is formed in a cross section in a water pipe radial direction.
The wall thickness of the recess on the refractory block side and the
A water pipe protection refractory structure characterized in that the structure is made substantially uniform . 2. The concave portion of the thick portion is a tapered concave portion.
Loosen the tapered recess and the tapered convex on the water tube side.
2. The water pipe protecting refractory structure according to claim 1 , wherein said fixing means is a fixing means fitted and fixed by fitting . 3. A water pipe side of a boiler from a combustion product of the boiler.
Between the water pipe side and the combustion gas side to protect the
Smell of fireproof structure for boiler water tube protection with block
The inner side faces the water pipe side, and the water pipe side faces the combustion gas side.
Formed so as to be substantially concealed, facing the outer surface of the water pipe
Refractory blower with a water tube enveloping part whose arcuate side is formed in an arc shape
On the opposite side of the refractory block and the water pipe side.
And a fixing means having an uneven shape for fixing the fixing means, and at least a part of the fixing means is in direct contact with the
The water pipe side and the refractory block are fixed in position, and a thin wall is provided between the refractory block other than the direct contact portion and the water pipe.
A refractory structure for protecting water pipes , characterized by being filled with mortar . 4. The water pipe envelope of a refractory block, wherein the fixing means is
The inner periphery of the cover is a projection that is in contact with the outer surface of the water pipe.
The refractory structure for protecting water pipes according to claim 3, characterized in that: 5. A refractory structure for protecting a boiler water pipe, comprising a refractory block interposed between the water pipe side and the combustion gas side in order to protect the water pipe side of the boiler from combustion products of the boiler. A fire-resistant structure for protecting a water pipe, comprising: a fire-resistant block including a number of small-diameter ceramic pipes in direct contact with a water pipe outer peripheral surface side; and fixing means for fixing the fire-resistant block to the water pipe side. body. 6. The water pipe protecting refractory structure according to claim 5 , wherein said water pipe side is constituted by at least two water pipes and a flat rib connecting between adjacent water pipes. 6. The water pipe protecting refractory structure according to claim 5 , wherein the small-diameter ceramic pipe group extends along the plane rib surface of the water pipe and is fixed on the plane rib surface via an anchor made of a high temperature resistant material. 7. A boiler water tube protection refractory structure in which a refractory block is interposed between the water tube and a combustion gas side to protect the water tube of the boiler from combustion products of the boiler, wherein at least two water tubes are provided. And a water tube side constituted by a planar rib connecting between adjacent water tubes, and an arc-shaped water tube covering portion formed along the surface shape of the water tube and the planar rib, and between the water tube covering portion. the refractory Bro comprises a refractory block obtained by a plane-like connecting portion for continuously arranged, and a fixing means for fixing in a state in which the planar connecting portion of the refractory block into contact with the flat rib of the water pipe side
Both the water tube wrapping part and the planar connecting part of the
A refractory structure for protecting water tubes, wherein the structure is in direct contact with the water tube side of the irra . 8. The refractory block is a semicircular water tube envelope.
Is formed from the parts and one planar connecting portion, the free end of the flat connecting portion was positioned fixed to engage the semi-circular water tube envelope part end face of the adjacent other side refractory block The refractory structure for protecting a water pipe according to claim 7 , characterized in that: 9. claims, characterized in Li Cheng that by ceramic bolts which arranged on the refractory block side as the fixing means
7. The fire-resistant structure for protecting a water pipe according to claim 7 . 10. The refractory block is a semicircular water pipe.
A semicircular arc formed of a wrapping portion and a flat continuous portion;
The fire-resistant structure for protecting a water pipe according to claim 7 , wherein the end face of the water pipe wrapping part and the free end side of the planar connection part of the adjacent other fire-resistant block are engaged and fixed by taper fitting. body.