JPH0926122A - Stoker type refuse incinerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To male it possible to cope with various kinds of refuse incineration and improve the combustion efficiency of the whole incinerator by using a fan-shaped fire grate for a dry stoker, and a step type fire grate for a combustion stoker and a post combustion stoker. SOLUTION: The refuse charged from a hopper 4 is fed to a dry stoker 5 by a refuse feeding device 8. In the dry stoker 5, each row of fan-shaped fire grates 18 are turned at an angle of elevation from about 60 to 70 deg. from the horizontal line so that the refuse may be erected. While turning over, the fire grates break up the lumps of refuse by agitating and move the refuse from the upper stage to the lower stage. The combustion stoker 6 feeds the refuse from the dry stoker 5 to the post combustion stoker 7 in a bonfire state by means of a step type fire grate 23 which agitates the refuse up-and-down, and back-and-forth direction by an offset between a stationary fire grate 24 and a movable fire grate 25 produced by a reciprocating motion of the movable fire grate 25. While agitating the refuse in a bonfire state in up-and-down and back-and-forth direction like the combustion stoker 6, the post combustion stoker 7 feeds the refuse to an ash receiving flap 9 by feeding forcibly a combustion air from a fan device, thereby producing the post combustion with the forced combustion air.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a stoker-type refuse incinerator with improved combustion efficiency.

[0002]

2. Description of the Related Art In a stoker-type refuse incinerator, a dry stoker, a combustion stoker, and a post-combustion stoker are arranged in a staircase order from the upper stage to the lower stage in the stoker, and in the dry stoker, waste heat is exchanged with combustion gas. Are dried with combustion air and combustion radiant heat that have been preheated by the above method, the dried dust is burned with a combustion stoker, and the incomplete combustion products are completely burned with a post combustion stoker, and the combustion ash is discharged from the lower part of the incinerator by a conveyor etc. Many are used.

In the stoker-type refuse incinerator, there are a stair-type grate stoker incinerator in which a stair-type grate is provided in each stoker, and a fan-type grate stoker incinerator in which a fan-type grate is provided in each stoker. Yes, the stair grate stoker incinerator
For example, as shown in Japanese Utility Model Publication No. 2-12435, a step type grate is used for a dry stoker, a combustion stoker, and a post-combustion stoker, respectively.

In the stair type grate, a fixed grate having a step shape and a movable grate having a step shape are alternately arranged in the furnace width direction, and the movable grate is reciprocated in the moving direction of the dust to form a fixed grate. The steps of the movable grate stir the dust up and down and back and forth to move it.

In this stair type grate stoker incinerator, since the stirring of dust in the combustion stoker and the post-combustion stoker is small, fly ash and dust are less, and the contact with the preheated air is good, so that the temperature is uniformly distributed in the high temperature region. It tends to burn and generate less dioxin, and is suitable for incineration of relatively low-moisture waste such as municipal waste.

The fan-type grate stoker incinerator uses the fan-type grate for a dry stoker, a combustion stoker, and a post-combustion stoker, respectively. The fan-shaped grate has a fan-shaped grate supported by a rotating shaft that is laid horizontally in the furnace width direction, and a plurality of fan-shaped grate are arranged in a stepwise manner in the direction of movement of dust. The grate of each row arranged toward
Approximately 70 degrees is sequentially rotated in the vertical direction to stir and move the dust.

In this fan-type grate stoker incinerator, the amount of stirring of the dust can be changed depending on the size of the diameter of the fan-type grate. Therefore, in the dry stoker, the stirring of the dust is increased by using the grate having a large diameter. For example, it facilitates the drying of high-moisture debris such as fishing village debris and the breaking of heavy-duty garbage in bags.

[0008]

However, since the stirrer-type grate stoker incinerator has less agitation of dust in the drying stoker, there is a tendency that the nodule-like dust collapse is insufficient and the drying efficiency deteriorates, resulting in a complete combustion. May not be promoted. In addition, in the fan-type grate stoker incinerator, even if the grate of the combustion stoker and the post-combustion stoker with a smaller diameter than the grate of the dry stoker is used, the agitation of dust is larger than that of the staircase type grate. Large amount of fly ash and dust. further,
In the case of waste with low water content and high calories burned, if drying in a dry stoker near the inlet is promoted, local combustion such as ignition / combustion occurs in the dry stoker, which adversely affects the post-stage stoker and post-burn stoker. The overall effect of the furnace is unbalanced.

Therefore, when various kinds of garbage are mixed as in recent years, it is difficult to incinerate efficiently in the conventional stoker type refuse incinerator in which the same grate is used.

Therefore, an object of the present invention is to provide a stoker-type refuse incinerator which can cope with incineration of various kinds of refuse and which improves the combustion efficiency of the entire incinerator.

[0011]

In order to achieve the above-mentioned object, the present invention provides a dry stoker, a combustion stoker,
In a stoker-type waste incinerator equipped with a post-combustion stoker, the means of claim 1 uses a fan-shaped grate for the dry stoker, and a stair-type grate for the combustion stoker and the post-combustion stoker, respectively. By increasing the agitation of (1), the drying efficiency of the waste is improved, and complete combustion in the combustion stoker and post-combustion stoker is promoted.

According to the second aspect of the present invention, a staircase type grate is used for the dry stoker and the post-combustion stoker, and a fan type grate is used for the combustion stoker to increase the agitation of dust in the combustion stoker. Promotes complete combustion. According to the means of claim 3, a stair-type grate is used for the drying and burning stoker, and a fan-type grate is used for the post-combustion stoker, and the agitation of dust in the post-combustion stoker is increased to move from the combustion stoker. The incompletely combusted material is well stirred to promote complete combustion.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below in more detail based on the embodiments shown in the drawings.

1 and 2 show a first embodiment of the present invention, in which a stoker-type refuse incinerator 1 comprises an incinerator body 2
A hopper 4 is provided at the upper part of the charging port 3 and the drying stoker 5, the combustion stoker 6, and the post-combustion stoker 7 are arranged in this order from the upstream of the moving direction of the waste in the incinerator body 2, and the drying stoker 5 is provided at the lower part of the charging port 3. A dust supply device 8 for supplying dust is provided, an ash receiver flap 9 is arranged downstream of the post-combustion stoker 7, and a drying stoker 5, a combustion stoker 6, a post-combustion stoker 7, and a bottom part of the ash receiver flap 9 each have a damper. Ash shoot 1
0, 11, 12, 13 are arranged, and each ash chute 10, 1
An ashing conveyor 14 is provided below 1, 12, 13.

An air blower 15 for supplying combustion air preheated by heat exchange with combustion gas from below the drying stoker 5, the combustion stoker 6, and the post-combustion stoker 7, respectively, is installed below the dust supply device 8. A re-combustion chamber 16 and a gas cooling chamber 17 are provided above the incinerator body 2.

The dry stoker 5 is composed of three rows of fan-shaped grate 1 in the upper, middle and lower stages from the upstream to the downstream of the direction of movement of dust.
8 is used. Each fan-shaped grate 18 has a rotating shaft 19 which extends through both side walls of the incinerator body 2 and is laid across in the furnace width direction.
A plurality of fan-shaped grate 20 fixed to the entire furnace width of the rotating shaft 19 and a lever 21 fixed to the end of the rotating shaft 19 protruding outside the furnace wall are connected to rotate. It is composed of a cylinder 22 for rotating the moving shaft 19.

The combustion stoker 6 and the post-combustion stoker 7 are
The staircase type grate 23 provided with a downward slope of about 10 degrees is used. The staircase type grate 23 has a movable grate in which a fixed grate 24 in which a plurality of steps of a grate is continuous and a movable grate 25 in which a plurality of steps of a grate is continuous are alternately arranged in the furnace width direction. Link 27 in which 25 is provided on the rotary shaft 26
And a rotary shaft 26 supported by a parallel link composed of a link 29 provided on the support shaft 28.
Is rotated to reciprocate the movable grate 25 in the moving direction of the dust, and the step between the fixed grate 24 and the movable grate 25 moves the dust to the downstream while stirring the dust up and down and back and forth.

The ash receiving flap 9 is rotated downward from the horizontal state by the operation of the cylinder 31, and the ash on the ash receiving flap 9 is dropped onto the ash chute 13.

In the stoker type refuse incinerator 1 thus constructed, the dust introduced from the hopper 4 is supplied to the drying stoker 5 by the dust supply device 8 in accordance with the combustion processing condition.
In the dry stoker 5, dust is caused by rotating the fan-shaped grate 18 of each row from an angle of elevation of about 60 to 70 degrees from the horizontal, and is stirred while being inverted to loosen the lumps and move from the upper stage to the lower stage. Combustion air from the blower device 15 is forcibly supplied from below the grate 20 through the gaps between the grate 20 to dry the waste, and the dried waste is stored in the combustion stoker 6 near the fan-shaped grate 18 in the lower stage. It is ignited by combustion radiant heat generated by combustion, combustion gas, etc., and sent to the combustion stoker 6.

In the combustion stoker 6, the dust sent from the drying stoker 5 is stirred up and down and front and back by the step difference between the fixed grate 24 and the movable grate 25 generated by the reciprocating movement of the movable grate 25, and the blower 15 Combustion air forcibly supplied from below is discharged from below the combustion stoker 6 through the gap between the fixed grate 24 and the movable grate 25 and the ventilation holes formed in each of the fixed grate 24 and the movable grate 25. It is blown up and completely burned, and the refuse in a bonfire state is sent to the post-burning stoker 7.

In the post-combustion stoker 7, the blower 15 is forced to stir the dust in the bonfire state up and down and forward and backward by the steps between the fixed grate 24 and the movable grate 25 generated by the reciprocating movement of the movable grate 25. It is post-combusted by the supplied combustion air and sent to the ash receiver flap 9.

Therefore, by using the fan-shaped grate 18 for the drying stoker 5, the dust is sufficiently disentangled by inversion and stirring, and the contact with the combustion air and the combustion radiant heat becomes large, so that the dust containing a large amount of water is contained. However, drying is averaged and efficient drying is promoted.

Further, since the movable grate 25 of the combustion stoker 6 is supported by the parallel link composed of the link 27 and the link 29, the movement of the dust in the front-rear direction is large and the movement in the up-down direction is small. Good contact with combustion air, radiant heat of combustion, and combustion gas promotes efficient and complete combustion through proper stirring and loosening of dust. Further, the amount of fly ash and dust in the combustion stoker 6 and the post-combustion stoker 7 is small.

Moreover, since the combustion efficiency is good, the average temperature in the furnace can be maintained in a high temperature range, so that the dioxin generation rate can be reduced.

FIG. 3 shows a second embodiment of the present invention. In this embodiment, the dry stoker 5 and the post-combustion stoker 7 are provided with a stepped grate 23, and the combustion stoker 6 is provided with a fan-shaped grate 18. The staircase type grate 23 used for the dry stoker 5 and the post-combustion stoker 7 has the same configuration as that of the first embodiment.

The fan-shaped grate 18 used in the combustion stoker 6 has a seven-row configuration, and a fan-shaped grate 32 having a smaller diameter than that in the first embodiment is provided over the entire furnace width of each rotary shaft 19. Multiple pieces are fixed.

With this structure, even if the dust in the drying stoker 5 is not sufficiently dried, the fan-shaped grate 18 used in the combustion stoker 6 can sufficiently loosen the dust by inverting and stirring the dust. In this way, good contact with combustion air, combustion radiant heat and combustion gas is achieved, and efficient complete combustion is promoted. Further, even in the case of waste with a small amount of water and high calories burned, early ignition / combustion in the drying stoker 5 can be suppressed, flashback combustion to the charging port 3 can be prevented, and sufficient waste can be dried.

FIG. 4 shows a third embodiment of the present invention. In this embodiment, the dry stoker 5 and the combustion stoker 6 are provided with the stair type grate 23 used in each of the embodiments.
The fan-type grate 18 used in the second embodiment is used for each of the post-combustion stokers 7, and the agitation of the dust in the post-combustion stokers 7 is increased to well agitate the incompletely combusted materials that have moved from the combustion stokers 6. To promote complete combustion.

[0029]

As described above, in the stoker-type refuse incinerator of the present invention, in the means of claim 1, the dry stoker is provided with the fan-type grate, and the combustion stoker and the post-combustion stoker are provided with the step-type grate. Since it is used, the agitation of the waste in the dry stoker is large, so that the waste is efficiently dried and the complete combustion in the combustion stoker and the post-combustion stoker is promoted. Further, in the means of claim 2, since the stair-type grate is used for the dry stoker and the post-combustion stoker, and the fan-type grate is used for the combustion stoker, the agitation of dust in the combustion stoker is large, so that complete combustion is promoted. It Further, in the means of claim 3, since the stair type grate is used for the drying and combustion stoker and the fan type grate is used for the post combustion stoker, respectively, the agitation of dust in the post combustion stoker is large,
The incompletely combusted material that has moved from the combustion stoker is well agitated to promote complete combustion.

Therefore, it is possible to deal with incineration of various kinds of waste, improve the combustion efficiency of the entire incinerator, and increase the incineration amount without increasing the size of the incinerator itself. In addition, since the combustion efficiency is good, the average temperature in the furnace can be maintained in a high temperature range, so that the generation rate of dioxins can be reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an incinerator showing a first embodiment example of the present invention.

FIG. 2 is a perspective view of each stoker.

FIG. 3 is a perspective view of each stoker showing a second embodiment example.

FIG. 4 is a perspective view of each stoker showing a third embodiment example.

[Explanation of symbols]

1 ... stoker-type refuse incinerator, 2 ... incinerator body, 5 ... dry stoker, 6 ... combustion stoker, 7 ... post-combustion stoker, 1
8 ... Fan type grate, 23 ... Stair type grate

Claims (3)

[Claims] 1. A stoker-type refuse incinerator having a dry stoker, a combustion stoker, and a post-combustion stoker in the furnace,
A stoker-type refuse incinerator, wherein a fan-type grate is used for the dry stoker, and a step-type grate is used for the combustion stoker and the post-combustion stoker. 2. A stoker-type refuse incinerator having a dry stoker, a combustion stoker, and a post-combustion stoker in the furnace,
A stoker-type refuse incinerator, wherein a stair-type grate is used for the dry stoker and the post-combustion stoker, and a fan-type grate is used for the combustion stoker. 3. A stoker-type refuse incinerator having a dry stoker, a combustion stoker, and a post-combustion stoker in the furnace,
A stoker-type refuse incinerator, wherein a stair type grate is used for the drying and burning stoker, and a fan type grate is used for the post-combustion stoker.