WO2019130719A1

WO2019130719A1 - Stoker-furnace sealing device and stoker furnace

Info

Publication number: WO2019130719A1
Application number: PCT/JP2018/037825
Authority: WO
Inventors: 勇紀小柴; 成貴小高; 寺部　保典; 勝秋元; 聡明小原
Original assignee: 三菱重工環境・化学エンジニアリング株式会社
Priority date: 2017-12-28
Filing date: 2018-10-10
Publication date: 2019-07-04
Also published as: CN110214249B; EP3734155A4; JP6393822B1; RU2744998C1; EP3734155B1; PH12020500214A1; EP3734155A1; TW201930784A; SG11202000754PA; BR112020008052A2; BR112020008052B1; CN110214249A; DK3734155T3; JP2019120414A; TWI683978B

Abstract

Provided is a stoker-furnace sealing device (30) that is provided with a plurality of fixed grates and a plurality of moving grates (16) and that seals the space between the moving grates (16) and a drop wall (27) of a stoker furnace that performs incineration of an object to be incinerated, while conveying the object to be incinerated. The stoker-furnace sealing device (30) includes: a front grate (31) that is disposed such that a distal end (31c) thereof is in contact with the moving grates (16); a supporting part (32) having a top-surface supporting plate (33) that is fixed to the drop wall (27) and that supports a top surface (31a) of the front grate (31) and a bottom-surface supporting plate (34) that is disposed below the top-surface supporting plate (33) and that supports a bottom surface (31b) of the front grate (31); and a spring (35) that biases the front grate (31) in the opposite direction from the direction in which the front grate (31) moves with movement of the moving grates (16).

Description

Stoker furnace seal device and stoker furnace

The present invention relates to a seal device for a stoker furnace and a stoker furnace. Priority is claimed on Japanese Patent Application No. 2017-253145, filed Dec. 28, 2017, the content of which is incorporated herein by reference.

As an incinerator which incinerates incinerated things such as waste, a stoker furnace which can be incinerated efficiently without selecting a large amount of incinerators is known. As a stoker furnace, what comprises stoke a stairway type and is provided with a drying stage, a combustion stage, and a post-combustion stage so that each function of drying, combustion, and a post-combustion can be performed is known.
In the stoker furnace equipped with the drying stage, the combustion stage, and the post-combustion stage, the seal hardware (pre-grate) is installed directly under the falling wall existing between the stages, and the moving grate is moved. And prevents the inflow of combustion air from other than the grate (see, for example, Patent Document 1).

Japanese Patent Application Laid-Open No. 4-186010

In the above-described conventional stoker furnace, the seal hardware can rotate about the pin and move up and down following the movement of the moving grate. However, rotational movement tends to adversely affect sealability. Also, if foreign matter gets caught between the seal hardware and the moving grate, the foreign matter can not be eliminated early and air may flow into the furnace from the caught gap, which may cause abnormal combustion. there were.

An object of the present invention is to provide a stoker furnace sealing device and a stoker furnace that can minimize the movement of a fore grate and suppress the reduction in sealing performance.

The seal device of the present invention comprises a plurality of fixed grates and a plurality of moving grates, and conveys the incineration material while transporting the material to be incinerated between the falling wall of the stoker furnace and the moving grate. A seal device for a stoker furnace for sealing, the front grate arranged so that its tip is in contact with the moving grate, and a top support plate fixed to the drop wall and supporting the top surface of the front grate A support portion having a bottom support plate disposed below the top support plate and supporting the bottom surface of the front grate, the front grate as the front grate moves as the moving grate moves And a spring biased in a direction opposite to the moving direction.

According to such a configuration, on the front grate dragged slightly by the moving grate, the spring exerts a pulling force in the direction opposite to the moving direction of the moving grate. For this reason, even when waste biting occurs between the moving grate and the fore grate, a force acts on returning the fore grate sandwiching the waste. In addition, since the movement of the fore grate is limited by the support portion, the movement of the fore grate can be minimized, and the decrease in sealability can be suppressed.

In the sealing device, a shaft-shaped member fixed to the front grate or the support portion and extending in one direction corresponding to the conveyance direction of the incineration material, and the shaft-like member being slidable in the one direction And a shaft support that supports the

According to such a configuration, the moving direction of the front grate can be restricted by the shaft-like member and the shaft support portion, and the contact state between the front grate and the moving grate can be improved.

The seal device includes a movement direction restricting portion for restricting the movement direction of the front grate to the advancing and retreating in one direction, and the movement direction restricting portion is a long penetration in the one direction formed in the front grate A hole may be provided, and a guide member may be inserted into the through hole and fixed to the support portion.

According to such a configuration, it is possible to further improve the contact state between the front grate and the moving grate by restricting the moving direction of the front grate by the movement direction limiting portion.

The stoker furnace on which the sealing device of the present invention is disposed is a drying stage, a combustion stage, and a post-combustion stage, each of which supplies a material to be incinerated from a feeder and includes a plurality of fixed grates and a plurality of moving grates. A sequential-type stoker furnace that performs drying, combustion, and post-combustion while sequentially transporting incineration materials, wherein the drying stage is disposed to be inclined such that the downstream side in the transport direction is directed downward, and the combustion is performed The stage is connected to the drying stage and is inclined such that the downstream side in the conveying direction is upward, and the post-combustion stage is connected to the combustion stage in the downstream direction such that the downstream side in the conveying direction is upward And the stack wall between the drying stage and the combustion stage in a state in which the front grate is pushed in the downstream direction of the transport direction, the seal for any of the above stoker furnaces Characterized by the arrangement of the device .

In the above-described stoker furnace, the seal device for any one of the above-mentioned stoker furnaces is applied to the falling wall between the feeder and the combustion stage in a state in which the fore grate is urged in the direction of drawing upstream May be arranged.

According to the present invention, it is possible to minimize the movement of the pregrate and to suppress the decrease in sealability, that is, to improve the sealability.

It is a schematic block diagram of the stoker furnace in which the seal | sticker apparatus for stoker furnaces of this invention is arrange | positioned. It is a figure explaining the stoker inclination angle of the stoker furnace of FIG. It is a sectional side view of the seal device provided in the first falling wall of the stoker furnace of FIG. FIG. 4 is a view on arrow IV-IV in FIG. 3 and is a cross-sectional view of the seal device of the present invention. It is a sectional side view of the seal device provided in the 2nd falling wall of the stoker furnace of FIG. It is a sectional side view of the seal device of the modification of the present invention. It is a figure explaining the modification of the stoker furnace in which the seal | sticker apparatus for stoker furnaces of this invention is arrange | positioned. It is a graph which demonstrates that the appropriate range of the stoker inclination angle of a drying stage is an angle between -15 ° and -25 °. It is a graph explaining that the appropriate range of the stoker inclination angle of a combustion stage is an angle between +5 degrees-+15 degrees. When both the drying stage and the combustion stage are considered, the appropriate range of the stoker inclination angle of the combustion stage is an angle between + 8 ° and + 12 °, and the optimum value is a graph for explaining the reason of + 10 °.

[Embodiment]
Hereinafter, a stoker furnace in which the seal device for a stoker furnace of the present invention is disposed will be described in detail with reference to the drawings.
The stoker furnace of the present embodiment is a stoker furnace for burning waste such as waste, and as shown in FIG. 1, the hopper 2 for temporarily storing the waste T and the incineration for burning the waste T The furnace 3, the feeder 4 for supplying the incinerator 3 to the incinerator 3, the stoker 5 provided on the bottom side of the incinerator 3 (the drying stage 11, the combustion stage 12, and the grate 15 of the post-combustion stage 13, 16), the wind box 6 provided below the stoker 5 and the head wall 27 (first head wall), 28 (second head wall), 29 (third head wall) of the stoker 5 And a seal device 30 (stoker furnace seal device).

The feeder 4 pushes out the incineration material T supplied onto the feed table 7 continuously through the hopper 2 into the incinerator 3. The feeder 4 reciprocates on the feed table 7 with a predetermined stroke by means of a feeder driving device 8.
The air box 6 supplies primary air from a blower (not shown) to each part of the stoker 5.
The incinerator 3 is provided above the stoker 5 and has a combustion chamber 9 consisting of a primary combustion chamber and a secondary combustion chamber. Connected to the incinerator 3 is a blower 10 for supplying secondary air to the combustion chamber 9.

The stoker 5 is a combustion device in which grates 15 and 16 are arranged in steps. The incinerator T burns on the stoker 5.
Hereinafter, the direction in which the incinerator T is transported is referred to as a transport direction D. The incinerator T is transported on the stoker 5 in the transport direction D. In FIG. 1, FIG. 2 and FIG. 3, the left side is the upstream side D1 in the transport direction, and the right side is the downstream side D2 in the transport direction. Also, the surface on which the

grate

15, 16 is attached is referred to as a mounting surface, and the drying stage 11, the combustion stage 12, or the horizontal surface and the installation centering on the upstream end (11b, 12b, 13b) of the post-combustion stage 13 The angle formed by the faces is called the stoker tilt angle (setting angle). If the transport direction downstream side D2 of the installation surface is upward from the horizontal plane, the stoker inclination angle is a positive value. If the transport direction downstream side D2 of the installation surface is downward from the horizontal plane, the stoker inclination angle is a negative value. I will explain here.

The stalker 5 has a drying stage 11 for drying the incinerator T, a combustion stage 12 for incinerating the incinerator T, and an unburned part completely incinerated sequentially from the transport direction upstream side D1 of the incinerator T, And a post-combustion stage 13 for combustion). In the stoker 5, the drying stage 11, the combustion stage 12, and the post-combustion stage 13 perform drying, combustion, and post-combustion, respectively, while sequentially transporting the incinerator T.
Each

stage

11, 12, 13 has a plurality of fixed grates 15 and a plurality of moving grates 16.
The fixed grate 15 and the moving grate 16 are alternately arranged in the transport direction D. The moving grate 16 reciprocates along the transport direction D. The reciprocation of the moving grate 16 transports and agitates the incinerator T on the stoker 5. That is, the lower layer portion of the incinerator T is moved and replaced with the upper layer portion.

The drying stage 11 receives the incinerator T which is pushed out by the feeder 4 and dropped into the incinerator 3, evaporates the water of the incinerator T, and partially decomposes it. The combustion stage 12 ignites the material T to be incinerated dried in the drying stage 11 by the primary air supplied from the lower air box 6, and burns the volatile matter and the fixed carbon content. The post-combustion stage 13 burns the unburned components such as fixed carbon components passed without being sufficiently burned in the combustion stage 12 until it is completely ashed.
An ash outlet 17 is provided at the outlet of the post-combustion stage 13. Ash is discharged from the incinerator 3 through the ash outlet 17.

Each of the drying stage 11, the combustion stage 12 and the post-combustion stage 13 has a drive mechanism 18 for driving a moving grate 16. That is, the drying stage 11, the combustion stage 12, and the post-combustion stage 13 separately have drive mechanisms 18 for driving the plurality of moving grates 16.

The drive mechanism 18 is attached to a beam 19 provided on the stoker 5. The drive mechanism 18 has a hydraulic cylinder 20 attached to the beam 19, an arm 21 operated by the hydraulic cylinder 20, and a beam 22 connected to the tip of the arm 21. The beam 22 and the moving grate 16 are connected via a bracket 23.

According to the drive mechanism 18, the arm 21 operates by the expansion and contraction of the rod of the hydraulic cylinder 20. The beam 22, which is configured to move along the mounting

surfaces

11a, 12a, 13a of the stoker 5 along with the operation of the arm 21, moves, and the moving grate 16 connected to the beam 22 is driven.

Although the hydraulic cylinder 20 is used as the drive mechanism 18, the present invention is not limited to this. For example, a hydraulic motor, an electric cylinder, a conductive linear motor or the like can be adopted. The form of the drive mechanism 18 is not limited to the form described above, and may be any form as long as the movable grate 16 can be reciprocated. For example, the beam 22 and the hydraulic cylinder 20 may be directly coupled and driven without arranging the arm 21.

The stoker furnace 1 has at least a part of the drying stage 11, the combustion stage 12, and the post combustion stage 13 at the same speed or driving speed of the moving grate 16 in the post combustion stage 13. Can be at different speeds.
For example, when the incineration material T required to be sufficiently burned in the combustion stage 12 is charged, the speed of driving of the moving grate 16 of the combustion stage 12 is reduced to reduce the incineration material on the combustion stage 12 The transport speed of T can be reduced to allow sufficient combustion.

As shown in FIG. 2, the fixed grate 15 and the moving grate 16 are such that the downstream side D2 in the conveying direction is upward with respect to the mounting

surfaces

11a, 12a, 13a of the drying stage 11, the combustion stage 12, and the post combustion stage 13. It is arranged to be inclined. Moreover, the

grate

15 and 16 is arrange | positioned so that the front-end | tip of the

grate

15 and 16 may face the conveyance direction downstream D2. Thereby, the movable grate 16 operates to send the incinerator T on the fixed grate 15 to the downstream side D2 in the transport direction.

A part of the moving grate 16 of the drying stage 11 is a projecting grate 16P (the others are normal grates described later). As shown in FIG. 2, the movable grate 16 in the range R1 of 50% to 80% from the end of the downstream side D2 in the transport direction D of the drying stage 11 becomes the protuberance grate 16P. ing. The use of the protuberance grate 16P can improve the stirring power.
The fixed grate 15 is a grate without projections on the top surface of the tip, and this shape is called a normal grate.

In the present embodiment, only the movable grate 16 is used as the projecting grate 16P. However, the present invention is not limited thereto, and both the moving grate 16 and the fixed grate 15 may be provided with the projecting grate.
Further, the range in which the protuberance grate 16P is provided is not limited to the above-mentioned range, and for example, all the grate of the drying stage 11 may be the protuberance grate 16P.
Furthermore, depending on the nature and type of the material T to be incinerated, all grates (fixed grate and moving grate) in the drying stage may be normal grates.

Similar to the drying stage 11, a part of the moving grate 16 of the combustion stage 12 is a projecting grate 16P. Specifically, the movable grate 16 in the range R2 of 50% to 80% from the end of the downstream side D2 in the transport direction D of the combustion stage 12 is the protuberance grate 16P. . The other moving grates 16 of the combustion stage 12 are normal grates. As in the drying stage 11, both the moving grate 16 and the fixed grate 15 may be provided with protrusions according to the nature and type of the material T to be incinerated, or all grates (fixed grate and moving grate ) May be a normal grate.
Although the grate of the post-combustion stage 13 is shown in FIG. 2 as the moving grate 16 and the fixed grate 15 as all normal grate, it is similar to the drying stage 11 and the combustion stage 12 with the projecting grate It may be adopted.

Next, the stoker inclination angles (installation angles) of the drying stage 11, the combustion stage 12, and the post-combustion stage 13 will be described.
As shown in FIG. 2, the drying stage 11 of the stoker 5 of the present embodiment is disposed downward. That is, the installation surface 11a of the drying stage 11 is inclined so that the downstream side in the transport direction is low. Specifically, the stoker inclination angle θ1 of the drying stage 11, which is the angle between the horizontal plane around the upstream end 11b of the drying stage 11 and the conveyance direction side of the mounting surface 11a, is -15 ° (minus 15 °) Is an angle between -25 ° (minus 25 °).

The combustion stage 12 of the stoker 5 of the present embodiment is disposed upward. That is, the installation surface 12 a of the combustion stage 12 is inclined so that the downstream side in the transport direction is high. Specifically, the stoker inclination angle θ2 of the combustion stage 12 which is the angle on the conveyance direction side of the mounting surface 12a with the horizontal plane centering on the upstream end 12b of the combustion stage 12 is from + 5 ° (plus 5 °) It is an angle between + 15 ° (plus 15 °).

The post-combustion stage 13 of the stoker 5 of the present embodiment is disposed upward. That is, the installation surface 13a of the post-combustion stage 13 is inclined so that the downstream side in the transport direction is high. Specifically, the stoker inclination angle θ3 of the post-combustion stage 13 which is the angle between the horizontal surface centering on the upstream end 13b of the post-combustion stage 13 and the conveyance direction side of the mounting surface 13a is + 5 ° (plus 5 ° ) Is an angle between + 15 ° (plus 15 °).

Between the feed table 7 and the drying stage 11, a first falling wall 27 (step) is formed. The stoker 5 has a first sealing device 30A that seals between the first falling wall 27 and the moving grate 16. The first seal device 30A is a device that prevents the inflow of combustion air from other than the grate when the moving grate 16 of the drying stage 11 moves.

As shown in FIG. 3, the first seal device 30A supports the front grate 31 disposed so that its tip (the transport direction downstream side D2) is in contact with the moving grate 16, and the front grate 31 so as to slide. And a spring 35 (compression coil spring) that biases the supporting part 32 and the front grate 31 in the direction opposite to the direction in which the front grate 31 moves as the moving grate 16 moves; And a movement direction restriction unit 44 for restricting the movement direction.
In the first sealing device 30A, the angle of the front grate 31 to the horizontal surface corresponds to the angle of the mounting surface 11a of the drying stage 11. That is, the front grate 31 of the first sealing device 30A is disposed such that the downstream side D2 in the transport direction is downward.
The moving direction of the front grate 31 is a direction along the conveying direction D, but strictly speaking, it is a direction along the mounting surface 11a of the drying stage 11 which is inclined so that the downstream side D2 is downward. .

The support portion 32 is fixed to the first falling wall 27 and fixed to the upper surface support plate 33 supporting the upper surface 31 a of the front grate 31 and to the upper surface support plate 33, and supports the bottom surface 31 b of the front grate 31. And a plate 34.

The front grate 31 has a rectangular plate shape, and includes a front grate main body 37 having a protrusion 31 c at its tip, and an axial member 38 connected to the rear end of the front grate main body 37. ing. An external thread groove is formed in at least a part of the shaft-like member 38.
As shown in FIG. 3 and FIG. 4, the front grate main body 37 is a rectangular plate-like member. The protrusion 31 c is formed to be in contact with the back surface 16 a of the movable grate 16. The protrusions 31 c extend in the width direction of the incinerator 3 (the direction orthogonal to the sheet of FIG. 1). By the projections 31c contacting the moving grate 16 across the width direction, the inflow of combustion air from other than the grate is prevented.

The upper surface support plate 33 is a plate-like member that supports the upper surface 31 a of the front grate 31. The upper surface support plate 33 and the front grate 31 are arranged such that the lower surface 33 a of the upper surface support plate 33 and the upper surface 31 a of the front grate 31 are in surface contact with each other.
The upper surface support plate 33 is disposed to be inclined such that the downstream side D2 in the transport direction is low. At the end of the transport direction D1 of the upper surface support plate 33, a first shaft support portion 40 slidably supporting the axial member 38 of the front grate 31 along the moving direction M of the front grate 31 is provided. It is provided. The first shaft support portion 40 of the present embodiment is a bearing provided on the first shaft support plate 39 formed by bending the upper surface support plate 33.

The bottom support plate 34 is a plate-like member that supports the lower surface 31 b of the front grate 31. The bottom support plate 34 and the front grate 31 are disposed such that the top surface 34 a of the bottom support plate 34 and the bottom surface 31 b of the front grate 31 are in surface contact with each other. The bottom support plate 34 is disposed such that the main surface of the top support plate 33 and the main surface of the bottom support plate 34 are parallel to each other.

The bottom support plate 34 is fixed to the top support plate 33 via a second shaft support plate 41 formed by bending an end portion of the bottom support plate 34 on the upstream side in the transport direction D1. The second shaft support plate 41 is provided with a second shaft support portion 42 which supports the shaft-like member 38 of the front grate 31 in cooperation with the first shaft support portion 40. The second shaft support portion 42 is a bearing provided on the second shaft support plate 41.

The first shaft support portion 40 and the second shaft support portion 42 are the direction M, which is one direction corresponding to the transport direction D, of the shaft-like member 38 of the front grate 31, and the upper surface support plate 33 and the bottom surface support It is supported along the direction parallel to the main surface of the plate 34. In other words, the shaft-like member 38 extends along the direction M by being supported by the first shaft support 40 and the second shaft support 42.
The movement of the front grate 31 in the direction orthogonal to the direction M is restricted by the upper surface support plate 33 and the bottom surface support plate 34, but the axial movement of the axial member 38 is not restricted.

The movement direction limiting portion 44 includes two long through holes 45 along the direction M formed in the front grate 31, and two guide members 46 inserted into the through holes 45 and fixed to the support portion 32. Have. As shown in FIG. 4, the through hole 45 is a long hole formed along the moving direction of the front grate 31. The guide member 46 is a rod-like member provided to connect the upper surface support plate 33 and the bottom surface support plate 34. The guide member 46 can be formed, for example, by a bolt.

The spring 35 is disposed between a nut 47 engaged with the male screw groove of the shaft-like member 38 and the first shaft support plate 39. The shaft-shaped member 38 is inserted inside the spring 35. One end of the spring 35 is fixed to the nut 47, and the other end of the spring 35 is fixed to the first shaft support plate 39. That is, the elastic force of the spring 35 acts on the nut 47 and the first shaft support plate 39.

The spring 35 of the seal device 30A of the first falling wall 27 is balanced in a state where it urges the front grate 31 in the direction of drawing the upstream side D1 toward the transport direction upstream. From this state, when the front grate 31 moves to the conveyance direction downstream side D2 with the movement of the movable grate 16 to the conveyance direction downstream side D2, the spring 35 is extended. By the spring 35 being extended from the balanced state, the front grate 31 is biased to the transport direction upstream side D1 (in the direction opposite to the direction in which the front grate 31 moves along with the movement of the moving grate 16). .

When the front grate 31 moves to the transport direction upstream D1 with the movement of the moving grate 16 to the transport direction upstream D1, the spring 35 contracts. When the spring 35 is contracted from the balanced state, the front grate 31 is biased to the downstream side D2 in the transport direction (opposite to the direction in which the front grate 31 moves with the movement of the moving grate 16).

A second falling wall 28 is formed between the drying stage 11 and the combustion stage 12. The end 11 c on the downstream side of the drying stage 11 in the transport direction is formed to be higher in the vertical direction than the end 12 b on the upstream side of the combustion stage 12 in the transport direction.
The second falling wall 28 is provided with a second sealing device 30B. As shown in FIG. 5, in the second seal device 30 </ b> B, the angle of the front grate 31 with respect to the horizontal plane corresponds to the angle of the mounting surface 12 a of the combustion stage 12. That is, the front grate 31 of the second sealing device 30B is disposed such that the downstream side D2 in the transport direction is upward.

The spring 35 of the second sealing device 30B is balanced in a state where it is urged in the direction of pushing the front grate 31 toward the downstream side D2 in the transport direction. From this state, when the front grate 31 moves to the conveyance direction downstream side D2 with the movement of the movable grate 16 to the conveyance direction downstream side D2, the spring 35 is extended. By the spring 35 being extended from the balanced state, the front grate 31 is biased to the transport direction upstream side D1 (in the direction opposite to the direction in which the front grate 31 moves along with the movement of the moving grate 16). .

Similarly, a third head wall 29 is formed between the combustion stage 12 and the post-combustion stage 13. The end 12 c of the combustion stage 12 on the downstream side in the conveyance direction is formed to be higher in the vertical direction than the end 13 b on the upstream side of the conveyance direction of the rear combustion stage 13.
A third seal device 30C is provided on the third head wall 29. The configuration of the third seal device 30C is the same as that of the second seal device 30B.

The spring 35 constituting the sealing device 30 can be adjusted by changing the position of the nut 47. The sealing device 30 of the present embodiment can extend the spring 35 by bringing the nut 47 close to the front grate main body 37.

Further, the end 12 c downstream of the combustion stage 12 in the transport direction and the end 13 c downstream of the post combustion stage 13 in the transport direction are substantially identical in the vertical direction, or the end of the post combustion stage 13 13 c is disposed above the end 12 c of the combustion stage 12. The stoker furnace 1 of the present embodiment is an example in which the end 12 c downstream of the combustion stage 12 in the conveyance direction and the end 13 c downstream of the post combustion stage 13 in the conveyance direction are at the same position in the vertical direction.

Next, the reason for setting the stoker inclination angle of the drying stage 11 to an angle between −15 ° (minus 15 °) and −25 ° (minus 25 °) will be described.
The function of the drying stage 11 is to dry the moisture in the incinerator T efficiently by radiant heat from the flame above the incinerator T and sensible heat of the primary air from under the grate.
Here, the radiation heat from the flame has a higher degree of contribution to drying than the sensible heat of the primary air, and the drying of the upper layer portion of the material T to be incinerated tends to proceed.
For this reason, the drying speed is improved by moving the lower layer portion of the incinerator T upward by the stirring operation by the grate and replacing it with the upper layer portion.
However, even if the stirring operation is performed, the drying stage 11 basically does not burn, so it is necessary to ensure a sufficient length for water evaporation to proceed. Since the longer the length, the larger the apparatus and the more expensive it is, it is required to shorten the stoker length as much as possible.

If the absolute value of the stoker inclination angle is larger than the repose angle of the incinerator T, it collapses under its own weight and a layer of the incinerator T is not formed. On the other hand, when the absolute value of the stoker inclination angle is made smaller than the repose angle of the incinerator T, the movement of the incinerator T by gravity (the movement by its own weight) is reduced although it is a stoker. Furthermore, when the mounting surface is upward, that is, when the stoker inclination angle is inclined at a positive value (positive value), the gravity acts to push back the incinerator T from the transport direction.
When the transport amount of the incinerator T by the stoker 5 is less than the amount of the incinerator T input, the transport limit is reached and the process becomes impossible.

The optimum stoker inclination angle varies depending on the amount of the incinerator T to be introduced and the moisture content of the incinerator T. Here, the case where the amount of incineration material T to be input is large and the moisture content is high (the amount of water content is large) will be described as a case where the input incineration material load is large. Conversely, when the amount of incineration material T to be introduced is small and the water content is low, the load on the incineration object to be injected is small.

In FIG. 8, the horizontal axis represents the stoker inclination angle of the drying stage 11, and the vertical axis represents the required stoker length of the drying stage 11. In the case where the loading incineration load is largest, the loading incineration load is smallest in order from (1) The case where the relationship between the stoker inclination angle of the drying stage 11 and the required stoker length of the drying stage 11 is plotted until case (4) is shown.
Here, the required stoker length is a distance at which 95% of the water content of the incineration material T to be input is dried. The “repose angle” on the horizontal axis indicates the repose angle of the material T to be incinerated.

As shown in the graph of FIG. 8, the stoker inclination angle of −30 ° is the limit for forming the layer of the incinerator T. With respect to the stoker inclination angle at the layer formation limit, the necessary stoker length decreases as the stoker inclination angle becomes loose, but when the stoker inclination angle turns to a positive value, the necessary stoker length gradually becomes longer. This is because when the stoker inclination angle becomes a positive value, the installation surface is upward and the transport speed is slowed, the layer of the incinerator T becomes thick, and the drying of the incinerator T in the lower layer portion hardly progresses It is because
From the four cases from when the load of the incinerator T to be input is the largest (1) to when the load of the incinerator T to be input is the smallest (4), the incinerator T has any property and amount Stoke inclination angle of the optimum drying stage 11 that can properly process even if there is the shortest stocker length is an angle between -15 ° (minus 15 degrees) and -25 ° (minus 25 degrees) It turns out that it is a range. The optimum value is -20 ° (minus 20 °).

Next, when the stoker inclination angle of the drying stage 11 is in the appropriate range as described above, the stoker inclination angle of the combustion stage 12 is between + 5 ° (plus 5 °) to + 15 ° (plus 15 °) The reason why it is suitable to use an angle will be described.
The function of the combustion stage 12 maintains the temperature of the layer of the incinerator T by radiant heat from the flame and self-combustion heat, promotes the generation of combustible gas by thermal decomposition of volatile matter, and burns fixed carbon remaining after thermal decomposition. It is something to do.

Here, since the time required to burn fixed carbon is longer than the time required to volatilize the volatile combustible gas, the required stoker length of the combustion stage 12 is determined by the time required to burn fixed carbon.

In FIG. 9, when the stoker inclination angle of the drying stage 11 is in the appropriate range as described above, the horizontal axis is the stoker inclination angle of the combustion stage, and the ordinate is the required stoker length of the combustion stage. The relationship between the stoker inclination angle of the combustion stage and the required stoker length of the combustion stage is plotted from the case where the load is the largest (1) to the case where the input incineration load is the smallest (4) in order. Here, the required stoker length of the combustion stage is a distance at which 95% of the combustible fraction evaporates or burns.

As shown in FIG. 9, the stoker inclination angle of −30 ° is the limit for forming the layer of the incinerator T. With respect to the stoker inclination angle at the layer formation limit, the required stoker length decreases as the angle becomes loose. In consideration of the transport limit, the appropriate range of the stoker inclination angle can be a range surrounded by a dashed dotted line shown in FIG.

Even in the case where the input incineration material load is large in the drying stage 11, since the drying stage 11 has the Stoker inclination angle in the appropriate range, the moisture content reduction and the volume reduction of waste are promoted. Therefore, for example, even if the load at the drying stage 11 corresponds to (1), the load at the combustion stage 12 changes to one corresponding to (3) and (4). The stoker inclination angle can be adopted. That is, by making the combustion stage upward, the residence time necessary for the combustion of fixed carbon can be secured, and the stoker length can be further shortened.

In FIG. 10, the horizontal axis represents the stoker inclination angle of the combustion stage 12, and the vertical axis represents the stoker length necessary for both the drying stage 11 and the combustion stage 12, and the load of the incinerator T to be input is largest (1) The plot of the relationship between the stoker inclination angle of the combustion stage 12 and the stoker length necessary for both the drying stage 11 and the combustion stage 12 until the load of the incinerator T to be input is smallest (4) in order from It is. Here, the stoker inclination angle of the drying stage 11 is set to the optimal value of −20 ° (minus 20 °).

As shown in FIG. 10, considering the transport limit, it can be seen that the appropriate range of the stoker inclination angle of the combustion stage 12 is an angle between + 8 ° (plus 8 °) and + 12 ° (plus 12 °). Further, when the stoker inclination angle of the drying stage 11 is −20 ° (minus 20 degrees) of the optimum value, the optimum value of the stoker inclination angle of the combustion stage 12 is + 10 ° (+10 degrees).
The necessary stoker length of the drying stage 11 and the combustion stage 12 can be made as short as possible by making each stoker inclination angle into an appropriate range, particularly an optimum value, and even if the post-combustion stage 13 is included A relatively small size and low cost stoker furnace can be used.

Since the drying stage 11 is inclined downward, any kind of incineration material T can be conveyed without problems to the combustion stage 12 and the combustion stage 12 and the post-combustion stage 13 are upward By inclining, the material T to be incinerated is sufficiently burned and transported downstream of the combustion stage 12 without easily slipping or rolling off.

That is, in the case of a slippery material or a to-be-incinerated material T having a rollable shape, the drying stage 11 is rolled or the like and conveyed to the combustion stage 12 at an early stage. However, since the combustion stage 12 and the post-combustion stage 13 are inclined upward, the incinerator T which has rolled down the drying stage 11 does not further roll down the combustion stage 12 and the post-combustion stage 13. Always be fully dried and incinerated. The material T to be incinerated with a high water content is transported to the combustion stage 12 while being dried without staying in the drying stage 11, so that it is certainly incinerated in the combustion stage 12 as well.
Thereby, the incinerator T can be continuously fed regardless of the property of the incinerator T, and the unburned residue of the incinerator T can be eliminated.

Further, the end 13c downstream of the post-combustion stage 13 in the transport direction is substantially the same position as the end 12c downstream of the combustion stage 12 in the transport direction in the vertical direction, or from the end 12c of the combustion stage 12 Also placed above. As a result, even if the incinerator T rolls off the drying stage 11 or the like, it is possible to prevent the incinerator T from being discharged from the post-combustion stage 13 without being sufficiently burned.

According to the above embodiment, the spring 35 applies a pulling force in the direction opposite to the direction of movement of the movable grate 16 on the front grate 31 dragged and moved slightly by the movable grate 16. For this reason, even when dust biting occurs between the moving grate 16 and the front grate 31, a force acts on returning the front grate 31 sandwiching the dust.
Further, since the moving direction of the front grate 31 is restricted by the support portion 32, the movement of the front grate 31 can be minimized, and the reduction in sealing performance can be suppressed.

In addition, the movement direction of the front grate 31 is restricted only by the shaft-like member 38 and the

shaft support portions

40 and 42 in the direction in which the front grate 31 contacts the moving grate. It can be improved.
Further, the moving direction restricting portion 44 configured by the through hole 45 and the guide member 46 can further improve the contact state between the front grate 31 and the moving grate 16.

Also, the direction in which the sealing device 30 of the present invention is pushed in the biasing direction as described above is applied to the stoker furnace in which the drying stage 11 faces downward at the above angle and the combustion stage 12 and the post combustion stage 13 face at the above angle. The sealability of the stoker furnace can be improved by appropriately setting and arranging in the “drawing direction” and the “drawing direction”.

The structure of the shaft-like member 38 of the sealing device 30 and the structure of the shaft support portion is not limited to the above-described structure. For example, as shown in FIG. 6, the shaft-like member 38B may be fixed to the support 32B (upper surface support plate 33B), and the cylindrical shaft support 40B may be fixed to the front grate main body 37. The spring 35 connects the nut 47 and the shaft support 40B. The shaft support portion 40B can slide on the inner peripheral surface of the through hole 41a formed in the second shaft support plate 41 of the bottom surface support plate 34.
That is, as long as the front grate 31 can be biased in the direction opposite to the direction in which the front grate 31 moves as the moving grate 16 moves, any configuration is possible.
Further, the sealing device 30 is not limited to the present embodiment, and can be effectively applied to a stoker furnace in which a plate-like moving grate exists just under the falling wall and reciprocates, but as in the present embodiment If the direction of inclination of each step is different, it is more preferable because the equipment cost can be reduced by the same mechanism.

[Modification]
Hereinafter, modifications of the stoker furnace in which the seal device for a stoker furnace of the present invention is disposed will be described in detail with reference to the drawings. In addition, in this modification, it describes focusing on difference with embodiment mentioned above, and abbreviate | omits the description about the same part.
As shown in FIG. 7, there is no level difference (falling wall) between the combustion stage 12 and the post-combustion stage 13 of the stoker 5. That is, the combustion stage 12 and the post-combustion stage 13 are connected continuously. In other words, the end 12 c downstream of the combustion stage 12 in the transport direction and the end 13 b upstream of the post-combustion stage 13 in the transport direction are formed to have the same height.
The second sealing device 30 B is provided only on the second falling wall 28 between the drying stage 11 and the combustion stage 12.

According to this modification, even if the momentum of the incinerator T which has rolled down the drying stage 11 is strong and the combustion stage 12 is passed by that momentum, it stops at least in the post-combustion stage 13 and from the post-combustion stage 13 It will not be discharged. And by the fact that the post-combustion stage 13 and the combustion stage 12 are continuously connected without a step, even if the to-be-incinerated material T which is not sufficiently burned up to the post-combustion stage 13 rolls and advances etc. Can be returned to the combustion stage 12 to perform combustion. That is, the discharge of the incompletely burned incinerator T can be reduced as much as possible.
Also in this modification, the sealability of the stoker furnace can be improved by appropriately setting the seal device 30 in the “push-out direction” and the “draw-in direction” as described above. Is the same as in the example.

The embodiment of the present invention has been described in detail with reference to the drawings, but the specific configuration is not limited to this embodiment, and design changes and the like within the scope of the present invention are also included.
The configuration for biasing the front grate 31 is not limited to the above-described configuration. For example, not the compression coil spring but a tension coil spring or a disc spring may be adopted.

DESCRIPTION OF SYMBOLS 1 stoker furnace 2 hopper 3 incinerator 4 feeder 5 stoker 6 air box 7 feed table 8 feeder drive device 9 combustion chamber 10 blower 11 drying stage 11a drying stage mounting surface 12 combustion stage 12a combustion stage mounting surface 13 post-combustion stage 13a Mounting surface of the post-combustion stage 15 Fixed grate 16 Moving grate 16P Protrusion grate 17 Ash outlet 18 Drive mechanism 19 Beam 20 Hydraulic cylinder 21 Arm 22 Beam 23 Bracket 27 First falling wall 28 Second falling wall 29 Third Head wall 30 Sealing device 30A First sealing device 30B Second sealing device 30C Third sealing device 31 Front grate

31a Upper surface

31b Lower surface 31c Protrusion (tip)
32 support portion 33 upper surface support plate 34 bottom support plate 35 spring 37 front grate

main body

38, 38B axial member 39 first shaft support plate 40 first shaft support portion 41 second shaft support plate 42 second shaft support portion 44 movement Direction limiting portion 45 Through hole 46 Guide member 47 Nut D Conveying direction D1 Conveying direction upstream D2 Conveying direction downstream T Incinerated material θ1, θ2, θ3 Stoker inclination angle

Claims

A sealing device for a stoker furnace which comprises a plurality of fixed grates and a plurality of moving grates, and seals between a falling wall of the stoker furnace which carries out incineration of the incineration material and the moving grate while transporting the incineration material. And
A front grate disposed with its tip in contact with the moving grate;
A support portion having a top support plate fixed to the falling wall and supporting the top surface of the front grate, and a bottom support plate disposed below the top support plate and supporting the bottom surface of the front grate ,
A seal device for a stoker furnace, comprising: a spring that biases the front grate in a direction opposite to a direction in which the front grate moves as the moving grate moves.
An axial member fixed to the front grate or the support and extending in one direction corresponding to the conveying direction of the incinerator material;
The seal apparatus for a stoker furnace according to claim 1, further comprising: a shaft support portion slidably supporting the shaft-like member in the one direction.
It has a movement direction restricting part which restricts the movement direction of the front grate to the one way advancing and retreating,
The movement direction restricting part is a through hole elongated in the one direction formed in the front grate;
The seal device for a stoker furnace according to claim 2, further comprising a guide member inserted into the through hole and fixed to the support portion.
The material to be incinerated is supplied from a feeder, and the material to be incinerated is sequentially conveyed in the drying stage, the combustion stage, and the post-combustion stage provided with a plurality of fixed grates and a plurality of moving grates, respectively, drying, combustion, And a post-combustion-type stoker furnace,
The drying stage is inclined so that the downstream side in the transport direction is downward,
The combustion stage is connected to the drying stage, and is disposed to be inclined such that the downstream side in the transport direction is upward,
The post-combustion stage is connected to the combustion stage and is disposed to be inclined such that the downstream side in the transport direction is upward.
In the falling wall between the drying stage and the combustion stage, in a state in which the fore grate is urged in a direction pushing the transport direction downstream, in any one of claims 1 to 3, A stoker furnace characterized in that the stoker furnace sealing device according to the invention is arranged.
The sealing device for a stoker furnace is disposed on the falling wall between the feeder and the combustion stage in a state in which the fore grate is urged in a direction to draw in the upstream side in the transport direction. The stoker furnace of item 4.