JP2001193909A - Melt processing apparatus for wastes such as incineration ash - Google Patents

Abstract

PROBLEM TO BE SOLVED: To develop a processing apparatus capable of reducing quantity of coke consumed as much as possible, and utilizing waste plastics as a heat source up to the utmost 100% in a melt processing apparatus for incineration ash. SOLUTION: A melting furnace 11 for processing wastes W such as incineration ash and the like is provided with a gas decomposing chamber 12 forming a specified space for introducing air fed to the lower part thereof, temporarily storing slug after melting, and thermally processing. An inlet 13 for air transporting fractions of waste plastics is faced to a portion of the gas decomposing chamber 12, and a gate 16 is arranged at the upper part of the chamber 12 to accelerate rising of decomposed gas and falling of molten slug. Further, a combustion melting chamber 17 is formed with a secondary air inlet 18 for accelerating incineration with the decomposed gas and for melt processing the wastes fed into the combustion melting chamber 17.

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 waste such as incineration ash, and more particularly to an apparatus utilizing waste plastic as a heat source.

[0002]

2. Description of the Related Art The components of incinerated ash are generally CaO 15-16.
_{%, SiO 2 35~36%, Al} 2 O 3 17~18%,
Others consisting of about 3%, 1300-1800 ° C
Conventionally, the incinerated ash is obtained by laminating coke and incinerated ash in layers alternately in a coke-filled shaft furnace.
The molten slag is led to 00 ° C., cooled, and crushed.

[0003] The treatment with 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. However, even in the case of the shaft furnace, 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 situation, and it is possible to minimize the amount of coke used and to use up to 100% of waste plastic as a heat source. It is intended to develop a processing device.

[0006]

SUMMARY OF THE INVENTION The melt processing apparatus of the present invention comprises:
In a melting furnace for melting and processing waste such as incineration ash, a certain space for thermally decomposing waste plastic was formed by introducing carrier air into the lower part of the melting furnace and temporarily retaining slag after melting. A gas cracking chamber is provided, and a part of the gas cracking chamber faces the inlet of the carrier air for carrying the waste plastic pieces, and the rising of the cracked gas and the dripping of the molten slag are performed at the top of the gas cracking chamber. A combustion melting chamber is formed facing the air inlet for arranging a roster to promote the combustion with the decomposition gas, and a waste is put into the combustion melting chamber to perform a melting process.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The melting apparatus according to the present invention comprises a melting furnace section 10 for melting waste S such as incineration ash and a waste plastic introducing section 30 for supplying waste plastic thereto.

As the melting furnace 11 of the melting furnace, a shaft type melting furnace can be used. The lower part of the melting furnace is used for receiving the below-mentioned carrier air and for temporarily retaining the slag G after melting. A gas decomposition chamber 12 forming a certain space is provided. A part of the gas decomposition chamber 12 is provided with an inlet 13 for the carrier air, the other side is provided with a burner 14 for performing initial preheating described later, and a lower part is provided with an outlet 15. . The inlet 13 may be used together with a relatively high-temperature air inlet pipe via a heat exchanger, as in the case of the secondary air described below. If necessary, the air may be enriched with oxygen. A vessel 19 may be provided.

On the gas decomposition chamber 12, there is arranged a rostre 16 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 17 to be filled with massive incineration ash S is formed. The combustion / melting chamber 17 partially faces a secondary air inlet 18 for promoting high-temperature combustion.
, Relatively high-temperature air that has passed through a heat exchanger with the combustion gas is supplied from an inlet pipe.

Further, a preheating chamber 2 for preheating massive incineration ash before combustion is provided above the combustion melting chamber 17 of the melting furnace 11.
0 is formed, and an inlet 21 for incineration ash and an exhaust port 22 for sending out exhaust gas after combustion are formed in the furnace head above it.

A conveying air pipe 31 is connected to the conveying air inlet 13 facing a part of the gas decomposition chamber 12, and a part of the pipe is cut into small pieces of an appropriate shape. A hopper 32 and a fixed-rate feeder 33 for storing plastic and sending it into the carrier air are provided. A blower 34 is provided at the end of the conveying air pipe 31. 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 waste plastic as a heat source of the present invention excludes chlorine-based 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, incinerator ash obtained by agglomerating the incinerated ash into a bean tongue or kneading the incinerated ash with cement into an agglomerate is dropped into the melting furnace 11 from the input port 21 using a charging machine or the like. I do. However, the incinerated ash is not limited to agglomerated one, and may be supplied as a powder.

Then, the process proceeds to preheating, ignites the burner 14, raises the temperature inside the furnace, stores heat in a refractory piece bed or the like, and guides the inside of the furnace to a high temperature of about 1500 to 1800 ° C. Then, as described above, CaO, SiO ₂ , Al ₂
The incinerated ash mainly composed of O 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 12 through the rostre 16.

At that time, the combustion of the burner 14 is stopped. On the other hand, the operation of the blower 34 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 32 into the transport air through the quantitative feeder 33, and the waste plastic is transported. It is sent into the gas decomposition chamber 12 through the inlet 13 together with air.

Then, in the gas decomposition chamber 12, since the molten slag stays at the bottom of the gas decomposition chamber 12, 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 that it 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 17 through the hole of the roastle 16, where it reacts with the air introduced from the secondary air inlet 18 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 massive incinerated ash smoothly reaches the melting point 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 lump incineration ash without any risk of clogging or the like, and has a combustion form suitable for melting. Becomes

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

[0021] The molten slag G is
And is stored at the bottom of the gas decomposition chamber 12 and acts as a molten slag for keeping the gas decomposition chamber at a high temperature. Then, it flows down from the discharge port 15 and is transferred to the original pulverizing process or the like. It is. This step is sequentially repeated.

Although incineration ash has been described as an example of the object of the above-mentioned treatment, the invention is not limited to such waste as long as it can be treated according to the same principle. It can be widely applied to metal scraps and others.

[0023]

The present invention has the following effects based on the above configuration and operation. (1) Since almost all of the waste plastic can be replaced with waste plastic without using coke as a heat source, energy costs can be greatly reduced, and plastic which is in need of disposal as waste is used. It is also 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 produce 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.

[Brief description of the drawings]

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Melting furnace part 11 Melting furnace 12 Gas decomposition chamber 13 Conveying air introduction port 14 Burner 15 Outlet 16 Rostor 17 Combustion melting chamber 18 Secondary air introduction port 19 Oxygen enricher 20 Preheating chamber 21 Input port 22 Exhaust port 30 Disposal Plastic introduction unit 31 Conveying air pipe 32 Hopper 33 Fixed-quantity feeder 34 Blower

 ──────────────────────────────────────────────────続 き 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 AA16 AB03 AC03 AC13 CA01 CA08 4D004 AA07 AA36 CA29 CB01 CB05 CB34 CB36 CB42 CC17 DA02 DA06

Claims (3)

[Claims] 1. A melting furnace for melting waste such as incineration ash, wherein a conveying air is introduced into a lower part of the melting furnace and a slag after melting is temporarily retained to thermally decompose waste plastic. A gas decomposition chamber having a certain space is provided, and a part of the gas decomposition chamber faces an inlet of a carrier air for carrying a small piece of waste plastic. Forming a combustion melting chamber facing the air inlet for promoting the combustion with the decomposition gas while arranging a rostelle for promoting the dropping of the molten slag, and introducing and melting the waste into the combustion and melting chamber. Melt processing equipment. 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.