JP3746941B2 - Stalker grate - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement in a stoker grate (grate) used in, for example, a waste stoker-type incinerator.
[0002]
[Prior art]
Conventionally, as this type of grate, for example, those described in JP-A-9-60851 and JP-A-9-210327 are known.
The grate is attached to the fire bed frame and has a hollow grate body in which an air passage is formed from the rear side to the front lower portion, and is detachably provided on the front side of the grate body. Formed between the sliding body that forms a part and is slidably engaged with the upper surface of the front grate body, and is formed between the front lower end of the grate body and the front upper end of the sliding body, and communicates with the air passage And an air outlet.
Therefore, such a grate is applied to the fixed grate and movable grate of the stair sliding type stoker arranged alternately in the front-rear direction, and regardless of the dust layer on the fire bed, Uniform combustion air is always sent from the outlet.
[0003]
[Problems to be solved by the invention]
However, in such a case, the dust and ash layers are thin in the downstream part of the combustion stoker where the waste is almost burned out and in the post-combustion stoker. As a result, excessive air is supplied to prevent the burning of the grate, resulting in an excess of air, leading to an increase in the amount of exhaust gas and an increase in NOx concentration. In addition, since combustion air is supplied from the air outlet into the incinerator with a large flow velocity, the amount of fly ash is increased by rolling up the ash deposited on the post-combustion stoker, which causes dust accumulation in the subsequent boiler. It was.
The present invention was devised in view of the problems described above, and was devised to solve this problem, and the problem was to prevent the supply of excessive combustion air and the scattering of ash deposited on the stoker, It is to provide a stoker grate that can achieve uniform air distribution.
[0004]
[Means for Solving the Problems]
The stoker grate of the present invention basically has a hollow grate body that is attached to a fire bed frame and has a hollow shape that is open at least below, and is provided on the front side of the grate body so that it can be raised and lowered. A sliding body that is slidably engaged with the upper surface of the lattice body, and a plurality of fine holes that are formed by making at least the grate body from a heat-resistant porous material and through which combustion air can pass. There is a feature in doing.
[0005]
When the movable grate is reciprocated in the front-rear direction with respect to the fixed grate, garbage is incinerated while being transferred from upstream to downstream of the fire bed.
Combustion air passes through the hollow portion from below the grate body and is injected into the incinerator from a large number of fine holes formed in the entire grate body.
As a result, supply of excess combustion air and scattering of ash deposited on the stoker are prevented, and uniform air distribution can be achieved.
At least the grate body is made of a heat-resistant porous material to form micropores, eliminating the need for conventional air outlets, simplifying the grate structure and reducing costs. You can plan.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a longitudinal side view showing an outline of a stoker grate according to a first example of the present invention. FIG. 2 is an enlarged longitudinal sectional view of FIG.
[0007]
The stalker grate (grate) 1 is composed of a grate body 2, a sliding body 3, and a fine hole 4, and the main parts thereof are alternately arranged in the front-rear direction (the waste feed direction, the left-right direction in FIG. 1). It is applied to either one or both of the fixed grate 101 and the movable grate 102 of the stair slide type stalker (stoker) 100 arranged in the above.
Thus, the grate 1 is generally employed in the downstream part of the combustion stoker and the post-combustion stoker among the stokers composed of drying, combustion and post-combustion.
[0008]
The grate body 2 has a hollow shape attached to the firebed frame 5 and at least opened downward. In this example, the upper wall 6, the front wall 7 connected to the front side of the upper wall 6, and these The left and right side walls 8 provided on both sides of the first and second side walls 8 and the hollow portion 9 formed by the left and right side walls 8 are opened, and the lower side and the rear side (left side in FIG. 1) are opened. The corners of the upper wall 6 and the front wall 7 are arcuate.
The grate body 2 is detachably attached to the fire bed frame 5 by the engaging means 10. The engaging means 10 allows lateral movement and prevents other movements. The ant 11 is provided at the upper part of the fire bed frame 5 and divided into front and rear, and a grate body adapted to the ant 11. The dovetail groove 12 is formed in the rear lower part of the two side walls 8. Thus, the grate body 2 is slid laterally and fitted into the firebed frame 5 by the engaging means 10. Such a mounting structure prevents the grate 1 from being lifted or lowered and absorbs thermal expansion and contraction. Of course, between the horizontal adjoining of the grate 1 is placed so as to be tightened from both ends of the grate 1 so that no gap is generated. If it does in this way, the grate 1 will be substantially fixed to the firebed frame 5, and it will not be necessary to apply the weight of the grate 1 to the sliding body 3. FIG. If the weight of the grate 1 is applied to the sliding body 3, wear of the sliding surface becomes intense, and it becomes necessary to replace it in a short time.
[0009]
The sliding body 3 is provided so as to be movable up and down on the front side of the grate body 2 and is slidably engaged with the upper surface of the preceding grate body 2. In this example, the sliding body 3 has a substantially convex cross section and is fitted. The front end is extended below the front end of the grate body 2 so as to be linearly raised and lowered while being always sealed by the coupling means 13. The fitting means 13 includes a concave groove 14 that is formed in the lower portion of the front wall of the grate body 2 and is opened at the lower side, and a ridge 15 that is fitted to the groove and protrudes from the upper portion of the sliding body 3. It is made up.
The sliding body 3 is made of a metal such as cast iron. However, if the material is different from that of the grate body 2, for example, a softer material than the grate body 2, wear of the grate body 2 can be reduced. . In this case, the sliding body 3 can be replaced when a certain amount of wear has occurred.
The sliding body 3 has a length that is 1 to 5 times (integer multiple) the lateral width of the grate body 2 and is slidably fitted on the upper surface of the preceding grate body 2 depending on its own weight. The longer this length is, the more the own weight increases and the degree of matching between the sliding body 3 and the preceding grate body 2 increases, and the leakage of the combustion air A from there decreases.
Since the sliding body 3 is detachably attached to the grate body 2 depending on the fitting means 13, the combustion air A depends on the fitting means 13 only when the sliding body 3 is worn down. Sealed at all times, combustion air A does not leak from here.
[0010]
The fine holes 4 are formed by producing at least the grate body 2 from a heat-resistant porous material, and are capable of passing the combustion air A. In this example, the grate body 2 is produced from the ceramic 16. In order that the combustion air A is uniformly ejected from the entire grate body 2, it is formed without any spots and has a diameter of about several tens to several hundreds μm. It has a size.
Thus, it is preferable that the grate body 2 has a so-called two-layer structure by attaching a metal punching metal 17 as a support inside the ceramics 16. The punching metal 17 is regularly provided with a large number of through holes 18 of about several mm. In this way, the defect of the ceramic 16 that is vulnerable to impact can be supplemented by the metal punching metal 17. Further, since the punching metal 17 does not receive direct combustion heat, it is not necessary to increase the amount of air for cooling.
[0011]
Next, the operation will be described based on such a configuration.
When the reciprocating drive device (not shown) is operated and the operating frame is moved in the front-rear direction, the movable grate 102 is reciprocated with respect to the fixed grate 101, and waste is incinerated while being transferred from the upstream to the downstream of the fire bed. The
Combustion air A is supplied to the hollow portion 9 from below the grate body 2 through the inside of the ash removal hopper, and more specifically, from a large number of fine holes 4 formed in the entire grate body 2. A large number of fine holes 4 formed in the entire ceramic 16 through a large number of through holes 18 are ejected to a dust layer on the fire bed.
[0012]
Since the grate body 2 is made of the ceramic 16, it is possible to prevent burning and to increase the temperature of the combustion air A without sending a large amount of the cooling combustion air A into the furnace. So it is effective for complete combustion.
Since excess combustion air A can be reduced, the amount of exhaust gas is reduced, and the scale of exhaust gas equipment can be reduced. Further, since the inside of the furnace does not become a strong oxidizing atmosphere, NOx can be suppressed.
[0013]
The combustion air A is injected from the fine holes 4 formed in the whole of the grate body 2 by utilizing the porosity of the ceramics 16 and sufficient ventilation resistance is obtained, so that uniform supply is possible. is there. Therefore, the ash that accumulates on the stoker is not rolled up, stable combustion is possible, and the amount of fly ash is reduced compared to the conventional one, so that dust accumulation in the subsequent boiler is reduced and the boiler water pipe The amount of wear is also reduced.
Since the grate body 2 is formed with the hollow portion 9, the upper wall 6 and the front wall 7 are cooled by the combustion air A passing therethrough, and burning is prevented even when receiving radiation heat from the dust layer. .
Since the grate body 2 is constructed by attaching a metal punching metal 17 inside the ceramic 16, it can be made resistant to impacts, and there is no problem in strength.
[0014]
Since the sliding body 3 is detachably provided on the grate body 2 and is always slidably engaged with the upper surface of the preceding grate body 2, the combustion air A does not leak from here, The incineration ash B on the grid body 2 can be pushed forward.
Since the fine hole 4 is formed in the whole grate body 2, the combustion air A can be ejected uniformly.
Since the fine hole 4 is a fine one having a diameter of about several tens to several hundreds of μm, the incinerated ash B is not likely to enter the hollow portion 9 from here, and this is blocked by the incinerated ash B. There is nothing to do.
The grate 1 does not require a conventional air outlet, so that complicated processing is not required and the cost can be reduced.
[0016]
In the above example, the grate 1 is applied to the downstream portion of the combustion stalker and the post-combustion stalker. However, the grate 1 is not limited thereto, and may be applied to a portion other than the downstream portion of the dry stalker or the combustion stalker, for example.
In the previous example, the grate body 2 has an arc shape at the corners of the upper wall 6 and the front wall 7.
In the previous example, the sliding body 3 is provided so as to be able to move up and down in a straight line.
In the previous example, the fine holes 4 are formed only in the grate body 2, but the present invention is not limited to this. For example, the fine holes 4 may be formed in both the grate body 2 and the sliding body 3.
[0017]
【The invention's effect】
As described above, according to the present invention, the following excellent effects can be obtained.
(1) Since it is composed of a grate body, a sliding body, and fine pores, and in particular, by forming at least the grate body from a heat-resistant porous material, a large number of fine holes through which combustion air can pass are formed. Supply of excess combustion air and scattering of ash deposited on the stoker are prevented, and uniform air distribution can be achieved.
(2) Since a large number of fine holes through which combustion air can pass are formed by making at least the grate body from a heat-resistant porous material, the conventional air outlet is unnecessary, and the structure of the grate Can be simplified and the cost can be reduced.
[Brief description of the drawings]
FIG. 1 is a longitudinal side view showing an outline of a stoker grate according to a first example of the present invention.
FIG. 2 is an enlarged vertical sectional view of FIG.

Claims (1)

A grate body that is attached to the fire bed frame and has a hollow shape that is open at least below, and is provided to be movable up and down on the front side of the grate body, and is slidably engaged with the upper surface of the preceding grate body It consists of a sliding body and a number of micropores that are formed by making at least a grate body with a heat-resistant porous material and through which combustion air can pass. The grate body is made of metal inside the ceramics. A stoker grate characterized by the fact that it is made up of an additional punching metal .

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