JPS609210B2 - Incinerator side wall structure - Google Patents

Description

[Detailed description of the invention] The present invention relates to an incinerator side wall structure.

The brick side wall that forms the internal combustion chamber of the incinerator, especially the part of this brick side wall facing the internal combustion zone, is used under extremely caustic conditions, so high-grade cinnamon carbide bricks (
SIC bricks) are used. This SIC brick has many advantages compared to other bricks in terms of wear resistance, erosion resistance, spall resistance, hot strength, etc.
The only drawback is that it oxidizes and expands in a high-temperature gas atmosphere, resulting in bulging of the ring walls. The causes of oxidation of SIC bricks are oxygen (02), carbon dioxide gas (C02),
Silicon carbide (SIC) is transformed into quartz (Si02) through an oxidation reaction in a high-temperature atmosphere of water vapor (20th June). As a physical phenomenon of oxidation, when SIC changes to Si02, the weight increases by 1.5 times, the volume approximately doubles, and the vertical ridge wall bulges into an arched shape. Therefore, the repair is
The entire wall will need to be replaced. Even in such an oxidizing atmosphere gas, the oxidation progress rate of SIC bricks varies depending on the gas temperature and moisture content. Generally, oxidation begins at a gas temperature of about 800 qo, but its progress is relatively slow and becomes more severe at a gas temperature of 100,000 qo or higher. This trend has already been experienced in actual plants. Particularly recently, in the case of municipal waste, which contains a large proportion of plastics, the gas temperature has also increased as the calorie content has increased rapidly, and the tendency of bricks to oxidize has become noticeable. The present invention is a method for repairing to eliminate various inconveniences that occur when bricks are oxidized, or for partial repairs or short-term repairs that do not require special techniques when building a furnace. This makes it easy to use a furnace, and also prevents oxidation caused by excessive rise in brick temperature, dramatically improving the durability of the bricks.

In the present invention, a large number of support plates are arranged in a lattice shape, and a stepped portion is provided at the center in the thickness direction, and the outer side of the furnace is smaller than the inner side of the furnace than the stepped portion, and the corner portions of the inner side of the furnace are of similar shape. Bricks with a cutout larger than the corner part of the outer side of the furnace are placed in parallel vertically and horizontally in a plurality of spaces surrounded by the support plate on the outer side of the furnace, and are formed by corresponding notches in adjacent bricks. The head of a bolt inserted into the through hole and screwed into a nut provided at the lattice point portion of the support plate and the nut connect the adjacent bricks to each other through the stepped portion created by the corner notch. It is held between the two.

Further, in the present invention, the backs of the connected bricks arranged in rows and columns are configured as air-cooled chambers, and the air-cooled chambers are communicated with combustion air supply pipes leading into the furnace via air supply pipes and exhaust pipes.

Embodiments of the present invention will be described below with reference to FIGS. 1 to 7.

An incinerator is shown in FIG.

The inside of the incinerator is equipped with a drying grate 1, a combustion grate 2, and a post-combustion grate 3 arranged in a stepped manner in this order. A water seal conveyor water tank 5 is provided. After the waste A is put into the input hopper 4 by a crane or the like, the moisture is evaporated on the drying grate 1, the flame is raised on the combustion grate 2, and it is vigorously incinerated at high temperature, and then the after-combustion grate 3 The ash B is finally burned up and discharged into the water seal conveyor water tank 5 as ash B with a small amount of combustible parts, where it is cooled and then taken out. Combustion gas generated in the furnace passes through an upper boiler 6 and is introduced into a flue 7. The boiler drum is number 8
It is indicated by. Almost the whole surface of the side wall 10 of the combustion furnace is made up of a large number of small bricks 11 at the same level in the lateral direction.
In the vertical direction, they are arranged in different steps or are stacked, but a part of it, that is, the part facing the in-furnace combustion zone, is made of SIC bricks 12A larger than the surrounding bricks 11 in the required number vertically and horizontally. It is constructed in a state in which brick connected bodies 12 arranged side by side are inserted. In the illustrated example, the in-furnace combustion zone is formed above the combustion grate 2 and above each portion of the drying grate 1 and the post-combustion grate 3. The bricks 11 in the portions not facing the internal combustion zone of the furnace are of the same quality and shape as those used as side wall bricks in the secondary chamber. As clearly shown in FIG. 6 and FIG. 7, each one of the SIC bricks 12A constituting the brick connection body 12
has a rectangular shape (for example, 500 mm x 50 mm x 12 mm) when viewed from the front, and has a stepped portion 13 at the center in the thickness direction, and the furnace outer side 12a is closer to the furnace inner side 12 than the hard part 13 of the bracket.
It has a similar shape smaller than b, and is formed so that each corner of the furnace outer part 12a and the furnace inner part 12b is cut out in a circular arc shape.

In this case, the notch 14B of the inner furnace part 12b is
It is larger than the notch part 14A of a. The brick connection body 12 described above is connected to a furnace body outer plate 15 that covers the outside of the side wall 10.

That is, as shown in FIGS. 2 to 5, a large number of SI
When the C bricks 12A are arranged vertically and horizontally with their notches 14 butted against each other, four adjacent SIC bricks 12A
A through hole 16 is formed by each notch 14 . This through hole 16 consists of a small light portion 16A and an enlarged diameter portion 16B, and the four
- The shaft portion 17A of the bolt 17 is inserted into the collar portion 16A.
At this time, the head 17B of the bolt 17 is received by the stepped portion 19 via the washer 18. On the other hand, a plurality of supporting members 20 are fixed to the outer plate 15 in the vertical direction. That is, a plurality of supporting members are provided at equal pitches so as to correspond to each joint extending in the longitudinal direction of the SIC brick 12A,
A large number of support plates 21 are arranged and fixed to these support members 20 in a grid pattern. A nut 22 is arranged between the lattice points, that is, between the end faces of the four support plates 21.
2 is fixed to the supporting material 2. That is, the plurality of SIC bricks 12A are placed in a plurality of spaces surrounded by four support plates 21,
The outer side portions 12a of each furnace are inserted into the saddle, and the tips of the bolts 17 are screwed into the nuts 22 and tightened. In other words, when the SIC bricks 12A are sequentially iron-inserted into a plurality of spaces surrounded by four support plates 21 via their furnace outer parts 12a, the plurality of SIC bricks 12A are arranged so that their furnace inner parts 12b are interchanged. They are arranged vertically and horizontally in contact with the
In this state, insert the bolt 17 into the through hole 16 through the washer 18.
is inserted, and its tip is screwed into the nut 22 to attach it vertically. Incidentally, casters are loaded into the expanded portion 16B. In this way, the four adjacent SIC bricks 12A are connected while being held between the bolt head 17B and the nut 22, thereby forming the brick connected body 12. In such a brick connecting body 12, only a specific SIC brick 12A can be easily replaced by removing the four bolts 17. In addition, in the embodiment shown in FIGS. 1 to 3, a small number of bricks 11 are placed along the slope of the grate.
are stacked in a predetermined shape, and a rectangular-shaped SIC brick 12A is placed above the brick 11 when viewed from the front, but as shown in Fig. 8, the lower part is shaped to match the slope of the fire grate. The configuration may be such that the SIC brick 12B is used and the rectangular SIC brick 12A is arranged above it. As shown in FIG. 2, a surrounding board 23 is provided around the space between the brick connected body 12 and the outer panel 15, and the inside thereof is used as an air cooling room 24.

As is clear from FIG. 2, the air pipe 2 is connected to this air cooling chamber 24.
5 and an exhaust pipe 26 are installed. That is, air pipe 2
5 is branched from a combustion air supply pipe 28 leading from the blower fan 27 into the furnace to reach the lower part of the air cooling chamber 24, and a damper 29 is interposed in the middle thereof. Also, the exhaust pipe 26
extends from the upper part of the air cooling chamber 24 to the terminal end of the combustion air supply pipe 28. The combustion air supply V supply pipe 28 includes an exhaust pipe 26.
A damper 30 is interposed between each connection portion of the air supply pipe 25. According to the above, a part of the combustion air can be bypassed through the air cooling chamber 24 by adjusting the opening degrees of the dampers 29 and 30 during furnace operation.

A portion of the bypassed combustion air at room temperature cools the brick joint 12 in the air cooling chamber 24, and is itself supplied into the furnace as combustion air after being heated. Therefore, prevention of oxidation of the brick connected body 12 and improvement of the combustion efficiency of the waste material A are achieved at the same time. In the illustrated example, the brick connection body 12 is composed of SIC bricks 12A, but this S
The thermal conductivity of IC brick is 12.7 Kcal/m°C (1
000°C), and 1
．． Compared to 2Kcal/mhqC (100p0), it is actually 1
It has twice as high thermal conductivity.

Therefore, the cooling effect by partially utilizing the combustion air described above works effectively, and even if the gas temperature in the furnace exceeds 1000° C., the temperature of the SIC brick 12A itself can be maintained at 900 qo or less. To maintain such an operating condition, a small bypass amount of combustion air of 25 mm/h to 30 mm/h per square meter of the cooling surface of the connected brick body 12 is sufficient. The inventor conducted continuous operation for about 2 years (1600 feeding hours) using the bypass amount described above.

As a result, there were no side wall bulging accidents, and when the SIC bricks were cut to investigate the progress of oxidation, no oxidation phenomenon was observed. Therefore, it is difficult to estimate the useful life of the connected brick body, and it is thought that it has a useful life of more than 10 years. Furthermore, the clinker (a molded product formed by melting the ash in the combustion gas and adhering to the brick surface) attached to the inner surface of the furnace was extremely thin and had good separation from the brick surface. At the same time, we also investigated the burnout caused by the heat of the support material made of ordinary carbon steel, the support plate and bolts made of stainless steel (SUS31I), but these hardware were also cooled, so there was no burnout at all.
Good results were obtained, with an unexpectedly long service life. Furthermore, we also investigated the initial construction status of the furnace. the result,
The time required to install the SIC bricks to form a brick connection was reduced to 1 hour by 3 workers, and the construction period was longer than the conventional Aoi Furnace method. Shinga drying costs are also no longer necessary. Moreover, it was found that the sophisticated and complicated Aoi Furnace technology used in the past was not required, and the work could be done with bare hands. As is clear from the above description, according to the present invention, the outside parts of the bricks are injected into the plurality of spaces surrounded by the support plates, and the opposing parts of the four bricks are fixed from inside the furnace with bolts. Therefore, not only is the furnace construction easy and the construction period shortened, but also specific bricks can be easily replaced by removing four bolts from inside the furnace.
Partial repair of the side wall can be carried out without using special techniques, and since the bolt head is located in the corner notch on the inside of the Shinga furnace, it is not directly exposed to the high temperature atmosphere of the furnace. There is no. Furthermore, when a part of the combustion air is bypassed through the air cooling chamber, the inconvenience caused by oxidation burnout of the side walls and bolts is completely eliminated, so the service life is dramatically extended. This enables continuous operation of the furnace over a long period of time.

[Brief explanation of drawings]

1 to 8 show embodiments of the present invention,
Fig. 1 is a schematic vertical side view of the incinerator, Fig. 2 is an enlarged sectional view corresponding to the 1-1 cross-sectional view taken in the direction of the arrow in Fig. 1, Fig. 3 is a view taken in the direction of the D arrow in Fig. 2, and Fig. 4 is an enlarged mm-m cross-sectional arrow view in FIG. 2, FIG. 5 is a view of W loss in FIG. 4, FIG. 6 is a front view of the SIC brick 12A, FIG. 7 is a side view of the same, and FIG. This is an explanatory diagram when using SIC bricks whose lower part has been shaped to match the slope of the fire grate. 2... Combustion grate, 10... Side wall, 1
1...Brick, 12...Brick connected body, 1
2A...SIC brick, 13...Stepped section, 1
4... Notch, 15... Furnace body outer plate, 16...
...Through hole, 17...Bolt, 17A...
Bolt shaft, 17B...Bolt head, 18...
Washer, 20...Support material, 21...Support plate, 22...
... Nut, 23 ... Circle board, 24 ...
...Air cooling room, 25... Air pipe, 26...
・Exhaust pipe, 28... Combustion air supply pipe, 29,
30...Damper. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8

Claims (1)

[Scope of Claims] 1. A large number of support plates are provided in a lattice shape, and have a stepped portion at the center in the thickness direction, and have a similar shape in which the outer side of the furnace is smaller than the inner side of the furnace than the stepped portion, and the inner side of the furnace is smaller than the inner side of the furnace. Bricks whose corner portions are cut out larger than the corner portions of the outer side of the furnace are placed side by side vertically and horizontally by fitting the outer side of the bricks into a plurality of spaces surrounded by the support plate, and the corresponding notches of adjacent bricks are placed side by side. The head of a bolt inserted into the through hole formed by the hole and screwed into a nut provided at the lattice point portion of the support plate and the nut connect the adjacent bricks to the step formed by the corner notch. An incinerator side wall structure characterized by being sandwiched between the parts. 2. A plurality of supporting members are provided in the vertical direction along the side wall of the incinerator, and a number of supporting plates are fixed to the supporting members in a lattice pattern, and a stepped portion is provided at the center in the thickness direction, and from the stepped portion to the outside of the furnace. A brick having a similar shape with a smaller part than the inside part and a corner part of the inside part being cut out larger than a corner part of the outside part of the furnace is placed in a plurality of spaces surrounded by the supporting plate with the outside part of the brick being cut out. Heads of bolts that are fitted and arranged vertically and horizontally, inserted into through holes formed by corresponding notches in adjacent bricks, and screwed into nuts fixed to the support material at the lattice points of the support plate. and the nut sandwich the adjacent bricks through the step formed by the corner notch, and connect the air cooling chamber formed by the supporting material to the combustion air supply pipe leading into the furnace. An incinerator side wall structure characterized by communication through an exhaust pipe.