Air-cooled furnace wall of garbage incinerator, furnace wall cooling air system and garbage incinerator

Abstract

The present invention discloses an air-cooled furnace wall of a garbage incinerator, a furnace wall cooling air system and a garbage incinerator. An air-cooled layer is arranged inside the air-cooled furnace wall, an S-shaped cavity loop is formed in the air-cooled layer, and the air-cooled layer also includes a cooling air inlet pipe arranged in the combustion section and a cooling air outlet pipe arranged in the front of the drying section and the rear of the burnout section. The cooling air inlet pipe and the cooling air outlet pipe are connected with the S-shaped cavity loop. The cooling air system includes an air-cooled furnace wall, a cooling air induced draft fan, a primary fan and a primary air preheater. The cooling air inlet pipe of the air-cooled furnace wall is connected with a cooling air source and the cooling air outlet pipe is connected with the inlet pipe of the cooling air induced draft fan. The outlet pipe of the cooling air induced draft fan is connected with the wind scoop below the grate sheet in the garbage incinerator through the primary fan and the primary air preheater in turn. The garbage incinerator includes the above-mentioned air-cooled furnace wall of the garbage incinerator or includes the above-mentioned air-cooled furnace wall of the garbage incinerator and the furnace wall cooling air system of the garbage incinerator. The present invention can solve the related problems of the prior art.

Description

Technical Field

[0001] The invention relates to the technical field of garbage incinerators, and more particularly to an air-cooled furnace wall of a garbage incinerator, a furnace wall cooling air system, and a garbage incinerator. Background Art

[0002] With the rapid development of social economy, my country's urbanization process is accelerating, the output of domestic waste is increasing rapidly, and many cities are facing the problem of garbage siege. Among various treatment methods, waste incineration power generation has the characteristics of resource utilization, reduction, and harmlessness. Waste incineration power generation is currently recognized as the most appropriate waste treatment method in China. In recent years, the coking problem of waste incinerators has been plaguing the normal operation of waste incineration power plants. Some waste power plants have to shut down their incinerators every three months or so due to the coking problem, which affects the economic benefits of the waste power plants.

[0003] An important reason for coking is that the furnace temperature is too high. When the calorific value of the garbage is too high, or the furnace is continuously overloaded, the furnace will overheat. If the temperature at this time is higher than the softening temperature T2 or the melting temperature T3 of the ash, coking will occur. On the other hand, the increase in the furnace temperature will inevitably cause the temperature of the outer wall of the furnace to rise. In order to reduce the outer wall temperature to below the specified temperature (50℃), the furnace wall needs to be made very heavy, which will inevitably increase the cost.

[0004] In order to solve the problem of coking of furnace wall and excessive temperature of furnace wall outer wall, some power plants use all-water-cooled furnace to solve this problem. However, when the calorific value of garbage is too low, the furnace temperature may not reach the required value, affecting the decomposition of dioxins. Even if some garbage incinerators use air-cooled furnace walls, these air-cooled furnace walls will have problems of arching, falling off or collapse after long-term operation. The reason is that these air-cooled furnace walls use large-area cavities. During the use of the furnace wall, the thermal stress caused by the temperature difference fluctuation in the furnace due to the fluctuation of garbage humidity or calorific value, and the structural stress caused by repeated stop and start operations, the high-temperature section of the furnace wall is concentrated and damaged. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention proposes an air-cooled furnace wall of a garbage incinerator and a furnace wall cooling air system and a garbage incinerator which avoid using a large-area cavity.

[0006] The present invention provides an air-cooled furnace wall of a waste incinerator, wherein an air-cooled layer is arranged inside the air-cooled furnace wall, and an S-shaped cavity loop is formed in the air-cooled layer, wherein the air-cooled layer also includes a cooling air inlet pipe arranged in the combustion section and a cooling air outlet pipe arranged in the front part of the drying section and the rear part of the burnout section, and the cooling air inlet pipe and the cooling air outlet pipe are connected to the S-shaped cavity loop.

[0007] According to an embodiment of the air-cooled furnace wall of a waste incinerator of the present invention, the air-cooled furnace wall, the front arch water-cooled wall, the rear arch water-cooled wall, the side wall water-cooled wall, the grate plate and the castables at the grate plate drop together form a closed furnace space of the waste incinerator, wherein the air-cooled furnace wall and the side wall water-cooled wall are connected by an expansion joint.

[0008] According to an embodiment of the air-cooled furnace wall of a waste incinerator of the present invention, the inner wall of the air-cooled furnace wall is in close contact with the side of the grate plate, and a wear-resistant plate is laid where the inner wall of the air-cooled furnace wall directly contacts the side of the grate plate.

[0009] According to an embodiment of the air-cooled furnace wall of a waste incinerator of the present invention, the air-cooled furnace wall includes five layers, which are, from outside to inside, an outer refractory brick layer, an aluminum silicate fiber felt layer, a lightweight thermal insulation castable layer, an air-cooling layer, and an inner refractory brick layer, wherein the air-cooling layer is formed by a partition wall embedded between the lightweight thermal insulation castable layer and the inner refractory brick layer to form the S-shaped cavity loop, and the layers on both sides of the air-cooling layer are fixed by V-shaped nails.

[0010] According to an embodiment of the air-cooled furnace wall of a waste incinerator of the present invention, each refractory brick layer and lightweight heat-insulating injection layer is provided with expansion joints at appropriate positions and ceramic fiber ropes are filled in the expansion joints.

[0011] According to an embodiment of the air-cooled furnace wall of a waste incinerator of the present invention, the air-cooled furnace wall is fixed to the outer wall panel by V-shaped nails, and double-jointed support members are welded on the outer wall panel, and the double-jointed support members are fixed on the columns; the entire air-cooled furnace wall is supported on the inclined H-shaped support members, and the H-shaped support members are fixed with a grate shaft support and a grate shaft connected to the grate plate, and the grate shaft support is isolated from the air-cooled furnace wall by a cover shell, and a circular hole for the grate shaft to pass through is opened on one side of the cover shell.

[0012] Another aspect of the present invention provides a cooling air system for the furnace wall of a waste incinerator, the cooling air system comprising an air-cooled furnace wall, a cooling air induced draft fan, a primary fan and a primary air preheater, the cooling air inlet pipe of the air-cooled furnace wall being connected to a cooling air source and the cooling air outlet pipe being connected to the inlet pipe of the cooling air induced draft fan, the outlet pipe of the cooling air induced draft fan being connected to the air scoop below the grate in the waste incinerator through the primary fan and the primary air preheater in turn.

[0013] According to an embodiment of the waste incinerator furnace wall cooling air system of the present invention, a temperature sensor is provided at the highest temperature point in the air-cooled furnace wall, and the temperature sensor monitors the furnace temperature in real time and transmits it to the automatic control system of the waste incinerator. The automatic control system adjusts the required cooling air volume based on feedback from the comparison between the measured temperature and the set temperature.

[0014] According to an embodiment of the waste incinerator wall cooling air system of the present invention, the inlet pipe of the primary air fan is also connected to the waste pit air source.

[0015] Another aspect of the present invention provides a waste incinerator, which includes the above-mentioned air-cooled furnace wall of the waste incinerator or includes the above-mentioned air-cooled furnace wall of the waste incinerator and the above-mentioned furnace wall cooling air system of the waste incinerator.

[0016] Compared with conventional solutions, the air-cooled furnace wall and furnace wall cooling air system of the waste incinerator of the present invention can increase the temperature drop of the refractory brick layer on the inner side of the furnace from about 5°C to about 60°C, and reduce the temperature of the outer wall of the furnace wall from more than 100°C to less than 50°C, compared with the waste incinerator without air-cooling structure, effectively solving the problem of over-temperature coking in the furnace and the problem of excessive temperature of the outer wall of the furnace wall, reducing non-stop caused by coking, and improving the efficiency of the waste incinerator. At the same time, the air-cooled furnace wall structure of the present invention is reinforced by the partition wall of the S-shaped loop, fixed by V-shaped nails, and reinforced by double-piece support members, making the furnace wall stronger and solving the problems of furnace wall arching, falling off, and collapse to a certain extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic structural diagram of a waste incinerator according to an exemplary embodiment of the present invention is shown.

[0018] Figure 2 A schematic diagram of the overall structure of an air-cooled furnace wall of a garbage incinerator according to an exemplary embodiment of the present invention is shown.

[0019] Figure 3 A partial structural schematic diagram of an air-cooled furnace wall of a garbage incinerator according to an exemplary embodiment of the present invention is shown.

[0020] Figure 4 A schematic structural diagram of an S-shaped cavity loop in an air-cooled furnace wall of a waste incinerator according to an exemplary embodiment of the present invention is shown.

[0021] Description of reference numerals:

[0022] 1-front arch water-cooled wall, 2-rear arch water-cooled wall, 3-side wall water-cooled wall, 4-air-cooled furnace wall, 5-expansion joint, 6-cooling air inlet pipe, 7-first cooling air outlet pipe, 8-second cooling air outlet pipe, 9-exterior wall board, 10-outer refractory brick layer, 11-aluminum silicate fiber felt layer, 12-lightweight thermal insulation castable layer, 13-V-type nails, 14-air-cooling layer, 15-partition wall, 16-inner refractory Brick layer, 17-expansion joint, 18-S-type cavity circuit, 19-temperature sensor, 20-grate plate, 21-casting material at the grate plate drop, 22-wear-resistant plate, 23-H-type support, 24-grate shaft support, 25-grate shaft, 26-cover, 27-double-jointed support, 28-column, 29-wind scoop, 30-cooling air induced draft fan, 31-primary fan, 32-primary air preheater. DETAILED DESCRIPTION

[0023] All features disclosed in this specification, or steps in all methods or processes disclosed, except mutually exclusive features and / or steps, can be combined in any manner.

[0024] Any feature disclosed in this specification, unless otherwise stated, can be replaced by other equivalent or alternative features with similar purposes. That is, unless otherwise stated, each feature is only an example of a series of equivalent or similar features.

[0025] The air-cooled furnace wall and furnace wall cooling air system and the garbage incinerator of the present invention are described in detail below.

[0026] Figure 1 shows a schematic structural diagram of a waste incinerator according to an exemplary embodiment of the present invention, Figure 2 The figure shows the overall structure of the air-cooled furnace wall of a garbage incinerator according to an exemplary embodiment of the present invention. Figure 3 A partial structural schematic diagram of an air-cooled furnace wall of a garbage incinerator according to an exemplary embodiment of the present invention is shown.

[0027] like Figures 1 to 3 As shown, according to an exemplary embodiment of the present invention, an air-cooling layer 14 is provided inside the air-cooling furnace wall 4 of the waste incinerator, and an S-shaped cavity loop 18 is formed in the air-cooling layer 14, wherein the air-cooling layer 14 further includes a cooling air inlet pipe 6 provided in the combustion section and a cooling air outlet pipe (such as Figure 1 The first cooling air outlet pipe 7 and the second cooling air outlet pipe 8 are shown in the figure, and the cooling air inlet pipe 6 and the cooling air outlet pipe are connected to the S-shaped cavity loop 18. Among them, the garbage incinerator is generally divided into a drying section, a combustion section and a burnout section according to the garbage treatment process, which is not described in detail in the present invention.

[0028] like Figure 1 and Figure 2 As shown, specifically, the air-cooled furnace wall 4, the front arch water-cooled wall 1, the rear arch water-cooled wall 2, the side wall water-cooled wall 3, the grate plate 20, and the castable 21 at the grate plate drop together form a closed furnace space of the waste incinerator, wherein the air-cooled furnace wall 4 and the side wall water-cooled wall 3 are connected by an expansion joint 5 to facilitate the release of the expansion margin of the air-cooled furnace wall 4 after being heated. The inner wall of the air-cooled furnace wall 4 is in close contact with the side of the grate plate 20. In order to delay wear, a wear-resistant plate 22 is laid where the inner wall of the air-cooled furnace wall 4 is in direct contact with the side of the grate plate 20.

[0029] like Figure 3As shown, the air-cooling furnace wall 5 in the present invention includes five layers, which are, from outside to inside, an outer refractory brick layer 10, an aluminum silicate fiber felt layer 11, a lightweight heat-insulating castable layer 12, an air-cooling layer 14, and an inner refractory brick layer 16. The air-cooling layer 14 is formed by a partition wall embedded between the lightweight heat-insulating castable layer 12 and the inner refractory brick layer 16 to form an S-shaped cavity loop 18, and the layers on both sides of the air-cooling layer 14 are fixed by V-shaped nails 13. Among them, the inner refractory brick layer 16 needs to withstand a higher temperature, for example, SIC refractory bricks can be selected; the outer refractory brick layer has a lower tolerance temperature, for example, B-1 refractory bricks can be selected.

[0030] The structure of the S-shaped cavity loop 18 is as follows: Figure 4 As shown, the setting of the S-shaped cavity loop is achieved by adjusting the length and arrangement direction of the partition wall. The setting of the S-shaped cavity loop 18 can reinforce the air-cooled furnace wall 4 to avoid arching and collapse, and can also make the cooling air flow more evenly and have a better cooling effect.

[0031] In addition, expansion joints are preferably provided at appropriate positions of each refractory brick layer and lightweight heat-insulating injection layer and filled with ceramic fiber ropes, so that each part has a certain expansion margin after being heated to avoid arching and collapse.

[0032] like Figure 2 and Figure 3 As shown, the air-cooling furnace wall 4 is fixed to the outer wall panel 9 by V-shaped nails 13, and the double-jointed support member 27 is welded on the outer wall panel 9, and the double-jointed support member 27 is fixed to the column 28; the whole air-cooling furnace wall 4 is supported on the inclined H-shaped support member 23, and the grate shaft support 24 and the grate shaft 25 connected to the grate plate 20 are fixed on the H-shaped support member 23, and the grate shaft support 24 is isolated from the air-cooling furnace wall 4 by the cover 26, and a circular hole is opened on one side of the cover 26 for the grate shaft 25 to pass through. Among them, the partition wall 15, the outer wall panel 9, the double-jointed support member 27, the H-shaped support member 23 and the cover 26 can all be steel parts.

[0033] like Figure 1 As shown, the waste incinerator furnace wall cooling air system of the present invention comprises an air-cooled furnace wall 4, a cooling air induced draft fan 30, a primary fan 31 and a primary air preheater 32, the cooling air inlet pipe 5 of the air-cooled furnace wall 4 is connected to the cooling air source and the cooling air outlet pipe is connected to the inlet pipe of the cooling air induced draft fan 30, and the outlet pipe of the cooling air induced draft fan 30 is connected to the air scoop 29 below the grate plate 20 in the waste incinerator through the primary fan 31 and the primary air preheater 32 in turn. Among them, the cooling air source is usually air from the external environment.

[0034] Thus, air from the external environment enters the air-cooling layer 14 of the air-cooling furnace wall 4 from the cooling air inlet pipe 6 as cooling air, flows through the S-shaped cavity loop 18 to cool the furnace wall, and is then drawn out from the cooling air outlet pipe (7, 8) through the cooling draft fan 30 and sent to the primary air preheater 32 through the primary fan 31. After being preheated by the primary air preheater 32, it enters the wind scoop 29 below the grate plate 20 and enters the furnace through the opening on the grate plate 20.

[0035] The amount of cooling air is related to the temperature rise of the cooling air. For example, when the temperature rise of the cooling air is 30°C, the amount of cooling air is about 1600Nm 3 / h, when the cooling air temperature rises to 80℃, the cooling air volume is about 600Nm 3 / h, when the cooling air temperature rises to 130℃, the cooling air volume is about 370Nm 3 / h. Preferably, a temperature sensor 19 is provided at the highest temperature point in the air-cooled furnace wall to monitor the furnace temperature in real time and transmit it to the automatic control system (ACC system) of the waste incinerator. The automatic control system adjusts the required cooling air volume based on the feedback of the comparison between the measured temperature and the set temperature.

[0036] Further preferably, the inlet pipe of the primary fan 31 is also connected to the garbage pit air source, so that the hot air drawn out from the cooling air outlet pipe (7, 8) will merge with the air from above the garbage pit and then enter the furnace after preheating, thereby being able to simultaneously process the garbage air.

[0037] Based on the above two-part structure, the present invention also provides a waste incinerator, which includes the above-mentioned waste incinerator air-cooled furnace wall or includes the above-mentioned waste incinerator air-cooled furnace wall and a waste incinerator furnace wall cooling air system.

[0038] That is, the air-cooling layer in the air-cooling furnace wall of the present invention avoids using a large-area cavity form, and adopts an S-shaped cavity loop. The S-shaped cavity loop is realized by a partition wall embedded in the refractory bricks (casting material) on both sides of the air-cooling layer. The air-cooling layer is close to the inner side of the air-cooling furnace wall. The cooling air enters the air-cooling layer from the highest temperature of the combustion section and flows in the air-cooling layer according to an S-shaped path. After cooling the air-cooling furnace wall, it flows out from the outlets at the front of the drying section and the rear of the burning section. The outflowing hot air is sent to the primary air circuit, and after being preheated by the preheater, it enters the wind scoop under the grate and is sent to the furnace, thereby realizing the recycling of heat. The temperature measuring points set in the air-cooling furnace wall can adjust the cooling air volume in real time according to the feedback of the furnace wall temperature, thereby ensuring that the temperature of the air-cooling furnace wall is maintained within a reasonable range, and avoiding the air-cooling furnace wall from being too hot and coking.

[0039] In summary, compared with the structure not adopting air cooling, the present invention can increase the temperature drop of the refractory brick layer on the inner side of the furnace from about 5°C to about 60°C, and reduce the temperature of the outer wall of the furnace wall from more than 100°C to less than 50°C, effectively solving the problem of over-temperature coking in the furnace and the problem of excessive temperature of the outer wall of the furnace wall, reducing non-stop operation caused by coking, and improving the efficiency of the waste incinerator; at the same time, the air-cooled furnace wall of the present invention is reinforced by the partition wall of the S-shaped loop, fixed by V-shaped nails, and reinforced by double-piece support parts, making the furnace wall stronger, and to a certain extent solving the problems of furnace wall arching, falling off, and collapse.

[0040] The present invention is not limited to the above-mentioned specific embodiments, but extends to any new features or any new combination disclosed in this specification, as well as any new method or process steps or any new combination disclosed.

Claims

1. An air-cooled furnace wall of a garbage incinerator, characterized in that: The air-cooling furnace wall is provided with an air-cooling layer inside, and an S-shaped cavity loop is formed in the air-cooling layer, wherein the air-cooling layer also includes a cooling air inlet pipe provided in the combustion section and a cooling air outlet pipe provided in the front of the drying section and the rear of the burnout section, and the cooling air inlet pipe and the cooling air outlet pipe are connected with the S-shaped cavity loop; the air-cooling furnace wall and the front arch water-cooling wall, the rear arch water-cooling wall, the side wall water-cooling wall, the grate plate and the castable at the grate plate drop together form a closed furnace space of the waste incinerator, wherein the air-cooling furnace wall and the side wall water-cooling wall are connected by an expansion joint; the air-cooling furnace wall includes five layers and is, from the outside to the inside, an outer refractory brick layer, a silicon Acid aluminum fiber felt layer, light insulation castable layer, air cooling layer and inner refractory brick layer, wherein the air cooling layer is formed by a partition wall embedded between the light insulation castable layer and the inner refractory brick layer to form the S-shaped cavity loop, and the layers on both sides of the air cooling layer are fixed by V-shaped nails; the air cooling furnace wall is fixed to the outer wall panel by V-shaped nails, and double-piece support members are welded on the outer wall panel, and the double-piece support members are fixed on the columns; the whole air cooling furnace wall is supported on the inclined H-shaped support members, and the H-shaped support members are fixed with a grate shaft support and a grate shaft connected to the grate plate, and the grate shaft support is isolated from the air cooling furnace wall by a cover shell, and a circular hole for the grate shaft to pass through is opened on one side of the cover shell.

2. The air-cooled furnace wall of a waste incinerator according to claim 1, characterized in that: The inner wall of the air-cooling furnace wall is in close contact with the side of the grate plate, and a wear-resistant plate is laid at the place where the inner wall of the air-cooling furnace wall directly contacts the side of the grate plate.

3. The air-cooled furnace wall of a waste incinerator according to claim 2, characterized in that: Each refractory brick layer and lightweight heat-insulating injection layer is provided with expansion joints at appropriate positions and ceramic fiber ropes are filled in the expansion joints.

4. A waste incinerator wall cooling air system, characterized in that: The cooling air system includes the air-cooled furnace wall, cooling air induced draft fan, primary fan and primary air preheater as described in claim 1, the cooling air inlet pipe of the air-cooled furnace wall is connected to the cooling air source and the cooling air outlet pipe is connected to the inlet pipe of the cooling air induced draft fan, and the outlet pipe of the cooling air induced draft fan is connected to the air scoop below the grate in the waste incinerator through the primary fan and the primary air preheater in turn.

5. The waste incinerator wall cooling air system according to claim 4, characterized in that: A temperature sensor is provided at the highest temperature point in the air-cooled furnace wall. The temperature sensor monitors the furnace temperature in real time and transmits it to the automatic control system of the waste incinerator. The automatic control system adjusts the required cooling air volume based on feedback from the comparison between the measured temperature and the set temperature.

6. The waste incinerator wall cooling air system according to claim 5, characterized in that: The inlet pipe of the primary fan is also connected to the garbage pit air source.

7. A garbage incinerator, characterized in that: The waste incinerator comprises an air-cooled furnace wall of the waste incinerator according to any one of claims 1 to 3 and a furnace wall cooling air system of the waste incinerator according to any one of claims 4 to 6.

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