JP2001193920A - Device for fusing incinerated ash, coupled with rotary kiln incinerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To develop a device which minimizes the quantity of used coke as far as possible when performing the fusion treatment of incinerated ash discharged from an incinerator and can utilize scrapped plastic to 100% at maximum as a heat source in the rotary kiln type of incinerator. SOLUTION: For this fusion disposer, a fusion furnace 20 is coupled with a discharge port for incinerated ash produced from a rotary kiln type of furnace 10. Fusion furnace 20 is constituted in such a way as (a) to arrange a gas cracking chamber 22, where a certain space for thermally cracking scrapped plastic by introducing carrying air and staying slag fusion temporarily is made at its lower part; (b) to let an introduction port 23 for carrying air for carrying in the pieces of scrapped plastic front on one pat of that gas cracking chamber; and (c) to form a combustion fusion chamber 27, where a luster 26 for accelerating the rise of cracked gas and the drop of fused slug is arranged above in that gas cracking chamber, and also an air introduction port for accelerating the combustion with cracked gas fronts on it, at its upper part of that gas cracking chamber, and to lead incinerated ash into that combustion fusion chamber so as to fuse it.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for melting and processing incinerated ash connected to a rotary kiln incinerator, and more particularly to a processing apparatus utilizing waste plastic as a heat source for the melting.

[0002]

2. Description of the Related Art Rotary kiln incinerators have been used as an effective means for disposing of viscous substances such as oil mud, tar, pitch, and paint, and powder and granular substances such as dye residue. The outline of the rotary kiln-type incinerator is, for example, in a case with a post-combustion stoker, a cylindrical kiln body, a driving unit for rotating the kiln, a supply unit for supplying waste to a combustion chamber in the kiln, And an air supply unit for supplying combustion air to the combustion chamber. A post-combustion stoker is connected to this, a secondary combustion chamber is provided thereon, and a discharge conveyor for discharging generated incineration ash is provided below. The components of the incinerated ash are generally CaO 15 ~
_{16%, SiO 2 35~36%,} Al 2 O 3 17~18
%, And about 3%, from 1300 to 180
Melting at a temperature of 0 ° C., conventionally, the incinerated ash is formed by laminating layers of coke and incinerated ash alternately in a coke-filled shaft furnace, and the heat of combustion of the coke is 1300 to 1300.
It is general that the molten slag is led to 1800 ° C., cooled, and crushed.

[0003] However, the treatment using the coke-filled shaft furnace has been evaluated as a method suitable for treating incineration ash because the furnace structure is simple and a high temperature in the furnace is easily obtained. 30 to 40% of coke of incinerated ash is required, and since the coke is expensive, there is a disadvantage that energy cost is high.

In view of the above, in order to improve the above, some methods have been attempted in which low-cost gas or oil and solid fuel are blown from an inlet so as to be used as auxiliary means for combustion by coke. And this solid fuel,
Means of using waste plastics are also being considered. However, when the waste plastic is put into the furnace as it is,
At the stage of melting, the coke becomes blocky and causes clogging of the coke having pores. Therefore, the amount of combustion is limited and is only 10% or less of the amount of coke burned.

[0005]

DISCLOSURE OF THE INVENTION The present invention has been made in order to solve the above-mentioned circumstances, and disposes viscous materials such as oil mud, tar, pitch and paint, and dusts and dusts such as dye residues. In a rotary kiln-type incinerator, the incinerator and the melting treatment device are connected, and the amount of coke used is minimized when melting the incineration ash discharged from the incinerator, The aim is to develop a device that can utilize up to 100% of waste plastic as a heat source.

[0006]

SUMMARY OF THE INVENTION The melt processing apparatus of the present invention comprises:
A cylindrical kiln is rotated around its axis, and combustion air is fed into the cylindrical kiln and connected to an outlet of incinerated ash generated from a rotary kiln incinerator formed by forming a combustion chamber, thereby forming a melting furnace. In the melting furnace, (a) a gas decomposition chamber is provided at a lower portion, in which a carrier air is introduced and a fixed space for thermally decomposing waste plastic by temporarily retaining the slag after melting is provided; A) A part of the gas decomposition chamber facing the inlet of the carrier air for carrying the waste plastic strips, and (c) a locator is provided at the upper part of the gas decomposition chamber to promote the rise of the decomposition gas and the dripping of the molten slag. At the same time, a combustion melting chamber is formed facing the air inlet for promoting combustion with the decomposition gas, and the incineration ash is guided to the combustion melting chamber for melting.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A melting treatment apparatus according to the present invention comprises a rotary kiln type incinerator unit 10, a melting furnace unit 20 for melting incineration ash S generated therefrom, and a waste plastic introduction unit for supplying waste plastic to the unit. 40.

The rotary kiln-type incinerator refers to an entire incinerator that rotates a cylindrical kiln around an axis, feeds combustion air into the inside, forms a combustion chamber, and performs a combustion process. Outside the furnace, there is provided a storage tank 11 for garbage, and a fixed amount supply device 12 for supplying a fixed amount of the waste into the furnace. A cylindrical kiln body 13 is formed, a driving part 14 for rotating the kiln body 13 around an axis is connected to a part thereof, a combustion air inlet 15 is provided on a side surface, and a starter burner 16 is provided below the inlet 15. Arrange. Then, a discharge port 17 for discharging the incinerated ash is formed at the end of the furnace.

Next, the rotary kiln incinerator unit 1
The melting furnace section 20 is formed by being connected to the discharge port 17 of the melting furnace. The form of connection between the discharge port 17 and the melting furnace section 20 is such that the melting furnace section 20 is disposed immediately below the discharge port 17 as shown in FIG. 1 or, although not shown, incineration ash once dropped from the discharge port Can be dropped from the input port 31 by a conveyor or the like. In any case, the powdered incinerated ash is kept in the melting furnace section 20 without any treatment such as agglomerating the incinerated ash with a binder or the like. Into the form.

As shown in FIG. 2, a shaft-type melting furnace can be used as the melting furnace 21 of the melting furnace section 20, and a slag G after melting is introduced into the lower part of the melting furnace while conveying air to be described later. A gas decomposition chamber 22 having a certain space for temporarily staying is provided. A part of the gas decomposition chamber 22 is provided with an inlet 23 for the carrier air, the other side is provided with a burner 24 for performing initial preliminary heating described later, and a lower part is provided with an outlet 25. . In addition, as with the introduction of the secondary air described later, a relatively high-temperature air introduction pipe via a heat exchanger may be used together with the introduction port 23. If necessary, the air may be enriched with oxygen. A vessel 29 may be provided.

On top of the gas decomposition chamber 22, there is arranged a roster 26 for promoting the rise of the decomposition gas and dripping of the molten slag, on which a refractory piece bed for preheating is arranged. A combustion melting chamber 27 to be filled with incineration ash S is formed.
A secondary air inlet 28 for promoting high-temperature combustion is partially exposed to the combustion / melting chamber 27. The secondary air inlet 28
Relatively high-temperature air that has passed through a heat exchanger with the combustion gas is sent from the inlet pipe.

Further, a preheating chamber 30 for preheating the incineration ash before melting is formed above the combustion melting chamber 27 of the melting furnace 21, and a discharge port of the kiln incinerator is provided at the furnace head above the preheating chamber 30. 17
Are linked.

A transport air pipe 41 is connected to the transport air inlet 23 facing a part of the gas decomposition chamber 22, and a part of the conduit is cut into small pieces of an appropriate shape. A hopper 42 and a metering device 43 for storing the plastic and sending it into the carrier air are provided. A blower 44 is provided at the end of the conveying air pipe 41. When the pressure in the furnace is high, the blower is configured to apply high pressure.
In addition, the above-mentioned plastic strips include granular ones.

The object of the waste plastic as the heat source of the present invention excludes chlorinated plastics and the like which generate toxic gas such as dioxin by combustion, but can be cut or molded into other suitable sizes. Including all plastics such as tires. In addition, rice husks, wood chips, waste paper, and the like may be mixed in the waste plastic as long as the melting temperature is not significantly reduced.

Next, the operation of the device of the present invention will be described. First, in the rotary kiln type combustion furnace section 10, when the stored dust is guided into the kiln body 13 via the quantitative supply device 12, the dust is burned by the flame of the starting burner 16 and the air from the combustion air inlet 15. At this time, since the cylindrical kiln body 13 is rotated around the axis by the driving unit 14, the entire dust is uniformly burned by the radiant heat of the combustion and the high-speed wall transfer heating. In this way, incineration ash is generated through the combustion by the kiln and is discharged through the outlet 17.

Then, the powdered incineration ash S is directly charged into the furnace from the charging port 31 of the melting furnace section 20 disposed below the discharge port 17. Alternatively, although not shown, when a conveyor or the like is used, powdery incineration ash is dropped from the conveyor.

Next, the process proceeds to preheating, in which the burner 24 is ignited to raise the temperature in the furnace, to store heat in a refractory piece bed or the like, and to guide the inside of the furnace to a high temperature of about 1500 to 1800 ° C. Then, as described above, CaO, SiO ₂ , Al ₂ O
_The incinerated ash mainly composed of ₃ or the like reaches the melting point, and a part of the molten slag is dropped to the bottom of the gas decomposition chamber 22 through the rostre 26.

At that time, the combustion of the burner 24 is stopped. On the other hand, the operation of the blower 44 for sending air is started, and on the way, the waste plastic cut into small pieces of an appropriate shape is sent out from the hopper 42 into the transport air via the quantitative feeder 43, and the waste plastic is transported. It is sent into the gas decomposition chamber 22 through the inlet 23 together with air.

Then, in the gas decomposition chamber 22, since the molten slag stays at the bottom of the gas decomposition chamber 22, 1500
When it is kept at a high temperature of １1800 ° C., and the waste plastic particles are carried by the carrier air, the plastic flakes are partially burned, but most of them are thermally decomposed into flammable gas. Metamorphose. That is, the gas decomposition chamber receives heat radiation from the molten slag staying therein, heat energy such as convection and the like, and the chamber is always kept at a temperature substantially equal to the melting temperature. Waste plastics such as are broken down at a stretch by intermolecular bonds and are thermally decomposed to change to combustible gas. As described above, under such a high temperature, if the introduced carrier air and the plastic as a combustible are present, they naturally burn, but part of the combustion and the burning of slag which will be described later. Do not hinder.

Here, the size and shape of the waste plastic to be carried in must be such that it can be pyrolyzed instantaneously and can be transported by air. Although small strips are desirable, it has been confirmed by the inventor's experiments that there is no problem with strips having a diameter of 20 mm or less.

Next, the combustible gas rises into the combustion and melting chamber 27 through the hole of the roastle 26, where it reacts with the air introduced from the secondary air inlet 28 to cause combustion. At this time, the value of the thermal calorie of the decomposed combustible gas of the waste plastic is 7000 kcal to 8000 kcal.
/ Kg, about 8000-9000 kcal
/ Kg, a very high calorie value, and the secondary air passed through the heat exchanger is kept at a relatively high temperature. Therefore, the combustion heat generated therefrom is equal to or higher than that of the conventional coke, and as a result, the incinerated ash reaches the melting point smoothly and becomes molten slag G.

At this time, the waste plastic is instantaneously gasified and comes into contact with the incineration ash and the like, so that the waste plastic surrounds the entire incineration ash and does not cause clogging or the like, and has a combustion form suitable for melting. .

Combustion of waste plastics by such means requires little coke and reduces coke by 10%.
Even with 0% replacement, our experiments were successful. However, use of coke as a heat source is not denied.

Then, the molten slag G is supplied to the Rostor 26
And is stored at the bottom of the gas decomposition chamber 22 and acts as a molten slag for keeping the gas decomposition chamber at a high temperature. Then, it flows down from the discharge port 25 and is transferred to the original pulverization processing and the like. It is. This step is sequentially repeated.

The object to be treated by the apparatus of the present invention can be widely applied to any kind of incineration ash discharged from a rotary kiln incinerator, such as steelmaking sludge, glass scrap, metal sludge, and metal scrap. It is.

[0026]

The present invention has the following effects based on the above configuration and operation. (1) Rotary kiln-type incinerators capable of incinerating a wide variety of garbage, such as oily mud, tar, pitch, paint, and other viscous materials, dye scum, and other powder and granular materials, and melt the incineration ash generated therefrom In the process, all can be replaced with waste plastic without using much coke as a heat source, so that the energy cost can be greatly reduced and the plastic that is in need of disposal as waste is used. Therefore, it is desirable from the viewpoint of resource utilization.

(2) Instead of burning the waste plastic as it is, it is once thermally decomposed at a high temperature to form a combustible gas, which is burned by mixing with the secondary air while surrounding the object to be treated. The heating mode is optimal for melting, for example, it has good contact efficiency and does not cause problems such as clogging.

(3) Further, in the thermal decomposition of the waste plastic, burning of the burner is required only at the beginning.
Thereafter, since the thermal energy of the molten slag as a by-product is used, the energy cost is further reduced.

(4) Since the powdery incineration ash generated from the roller-lee kiln incinerator can be directly connected to the melting furnace without being treated in a lump with a binder or the like,
Labor saving in the process becomes possible.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of the device of the present invention.

FIG. 2 is an enlarged sectional view of a main part of the device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Rotary kiln type incinerator part 11 Garbage storage tank 12 Quantitative supply device 13 Kiln main body 14 Drive part 15 Air inlet 16 Starter burner 17 Discharge port 20 Melting furnace part 21 Melting furnace 22 Gas decomposition chamber 23 Transport air inlet 24 Burner 25 Discharge port 26 Rostor 27 Combustion and melting chamber 28 Secondary air inlet 29 Oxygen enricher 30 Preheating chamber 31 Furnace head 40 Waste plastic introduction section 41 Conveyor pipe 42 Hopper 43 Quantitative feeder 44 Blower

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Noriyuki Inoue 6-6-4 Joto, Oyama-shi, Tochigi F-term in Chiyoda Engi Co., Ltd. (Reference) 3K061 AA08 AA16 AB02 AB03 AC03 AC13 CA01 CA08 DA15 DB16 DB20 FA02 FA10 FA26 KA02 KA15 KA27 NB03 NB08 NB27 4D004 AA07 AA11 AA12 AA36 CA29 CB01 CB09 CB34 CB47 CC17 DA02 DA06

Claims (3)

[Claims] 1. Rotating a cylindrical kiln about an axis,
A combustion furnace is formed by feeding combustion air into the inside of the furnace and connected to an outlet of incineration ash generated from a rotary kiln-type incinerator formed by forming a combustion chamber. And a gas decomposition chamber in which a fixed space for thermally decomposing the waste plastic by temporarily retaining the molten slag is disposed. (B) The waste plastic is disposed in a part of the gas decomposition chamber. (C) A rooster for raising the decomposition gas and dripping molten slag is disposed at the upper part of the gas decomposition chamber, and an air introduction port for promoting the combustion with the decomposition gas. A melting treatment apparatus characterized by forming a combustion melting chamber facing the combustion chamber, and guiding incineration ash to the combustion melting chamber for melting processing. 2. The melt processing apparatus according to claim 1, wherein a burner for preheating is provided in a part of the gas decomposition chamber. 3. The melting treatment apparatus according to claim 1, wherein a refractory piece bed for preheating is provided in a part of the combustion melting chamber.