JP2003021317A - Incinerated ash fusing system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure stable electric power. SOLUTION: An incinerated ash fusing system, which fuses incinerated ash 1 in a fusion furnace 5 after drying treatment 2 and discharges it after performance of secondary combustion treatment 11 of exhaust gas 10 generated in the fusion furnace 5 and performs heat treatment 18 for crystallization after crushing the fused slag 15 generated in the fusion furnace 5, has a power source 18 which is fed with electric power by a cogenerating power source 25 generating exhaust heat and supplies power to the fusion furnace 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an incineration ash melting system for reprocessing waste incineration ash for volume reduction or the like, and more particularly to an incineration ash melting system capable of obtaining stable power.

[0002]

2. Description of the Related Art In recent years, it has become difficult to secure a final disposal site for general waste, and the volume of waste incineration ash has been greatly reduced.
It is becoming necessary to extend the life of the final disposal site by making it harmless and recycling it. Therefore, there is an urgent need to spread an incineration ash melting system that melts the incineration ash at a high temperature and treats the exhaust gas and the molten slag.

FIG. 2 is a block diagram showing the structure of a conventional incineration ash melting system. An electrode 6 is arranged inside the melting furnace 5, and the electrode 6 is fed from a power source 8 connected to a power system 9. The incineration ash 1 of waste is sent to the melting furnace 5 through the drying process 2. In the melting furnace 5, the incineration ash 1 is heated to a high temperature to become the molten metal 7, and the waste gas 10 generated there is cooled by the cooling process 12 after the secondary combustion process 11 is performed. Adsorption processing 1
After being rendered harmless by 3, the release process 19 to the outside air is performed. On the other hand, the molten slag 15 of the molten metal 7 is cast by the casting process 1
After 6 is performed, a crushing process 17 is performed, and further artificial gravel 19 is formed through the heat treatment 18 and becomes reusable. Further, the molten metal 20 in the molten metal 7 is also taken out.

In FIG. 2, since the incinerated ash 1 contains a large amount of water, a drying treatment 2 of heating with a drying kiln or the like is necessary as a pretreatment. The pretreatment prevents clogging of the device. Moisture generated in the drying process 2 is discharged by the waste gas process 3. Also,
After the drying treatment 2, the incinerated ash 1 is charged with an additive 4 for increasing the fluidity of the molten metal 7 and reducing the molten metal 7. The melting furnace 5 includes various types such as a DC electric resistance furnace, an AC electric resistance furnace, an arc furnace, and a plasma furnace, and a DC voltage or an AC voltage is applied to the electrode 6 depending on the type of the melting furnace 5. When the melting furnace 5 is a direct current electric resistance furnace or an alternating current electric resistance furnace, the electrode 6 is inserted into the molten metal 7, but when the melting furnace 5 is an arc furnace or a plasma furnace, the electrode 6 is the molten metal 7. Placed on top of. Molten slag 15 is recrystallized by heat treatment 18 and artificial gravel 1
9 increases the mechanical strength. The waste gas 10 is subjected to a secondary combustion process 11 for removing metal components contained therein and for preventing generation of dioxins, and a cooling process 12 for rapid cooling.

The heat sources in the drying process 2, the secondary combustion process 11, and the heat treatment 18 are conventionally heavy oil and LN.
Burners using G, LPG, etc. as fuel, heaters by electric resistance, induction heating by high-frequency voltage, etc. have been used.

[0006]

However, in the conventional incineration ash melting system as described above, there is a case where the power system loses power due to lightning or the like, and the dissolved matter of the incineration ash solidifies, making it difficult to restart the operation. There was a problem of becoming. That is,
If the incineration ash melt is cooled by a power failure and once solidifies, it is necessary to remove the solidified product in order to restart the operation. For that purpose, the incineration ash melting system had to be disassembled, and it took a considerable time to restart the operation. If the incinerator ash melting system is not operated with stable power without blackout, the processing speed of waste will be reduced and environmental problems will be spread.

An object of the present invention is to secure stable electric power.

[0008]

In order to achieve the above object, according to the present invention, after the incineration ash is dried, it is melted in the melting furnace, and the exhaust gas generated in the melting furnace is subjected to the secondary combustion processing. In the incineration ash melting system in which the heat treatment for crystallization is performed after the molten slag generated in the melting furnace is crushed after being discharged, the power source for supplying power to the melting furnace discharges waste heat. Power should be supplied from the cogeneration power source that is generated. As a result, since the power system is not used for power supply to the melting furnace, power failure due to lightning or the like will not occur and stable power can be secured.

Further, in such a structure, the exhaust heat may be used as a heat source for the drying process. This will improve the efficiency of the incineration ash melting system. Further, in such a configuration, the exhaust heat may be used as a heat source for the secondary combustion process. This will improve the efficiency of the incineration ash melting system.

Further, in this structure, the exhaust heat may be used as a heat source for the heat treatment. This will improve the efficiency of the incineration ash melting system.
Further, in such a configuration, the cogeneration power source may be provided with a further auxiliary heat source. Thereby, when the exhaust heat is insufficient, the heat from the auxiliary heat source can be supplied.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below based on embodiments. FIG. 1 is a block diagram showing the configuration of an incineration ash melting system according to an embodiment of the present invention. The power source 8 receives electric power from the cogeneration power source 25, and the heat sources for performing the drying process 2, the secondary combustion process 11, and the heat treatment 18 are the cogeneration power source 25 as indicated by dotted lines 22, 23, and 24.
Sourced from. 1 is the same as the conventional configuration of FIG. 2, and the same portions as those of the conventional one are denoted by the same reference numerals and detailed description thereof will be omitted.

In FIG. 1, the cogeneration power source 25 is a generator having a high exhaust heat temperature such as a gas turbine or a gas engine. Electric power from this generator is supplied to the power source 8 and the exhaust heat is passed through a heat exchanger. Then, the temperature is set to a desired temperature and used as a heat source in the drying process 2, the secondary combustion process 11, and the heat treatment 18. Since the power from the power grid is not used, there is no power outage due to lightning, and stable power can be secured. Therefore, the operation of the incineration ash melting system does not stop due to a lightning strike or the like, and the efficiency of the incineration ash treatment is improved. Further, since the exhaust heat from the cogeneration power source 25 is used as a heat source in the drying process 2, the secondary combustion process 11, and the heat treatment 18, the efficiency of the incineration ash melting system is further improved, and the inexpensive operation becomes possible.

Although not shown in FIG. 1, an auxiliary heat source such as a burner or an electric heating source is provided separately from the cogeneration power source 25, and when the amount of heat exhausted from the cogeneration power source 25 is insufficient, It is preferable that heat can be supplied from the auxiliary heat source to the drying process 2, the secondary combustion process 11, and the heat treatment 18. The auxiliary heat source may be smaller than in the case of the heat source of the conventional drying process 2, the secondary combustion process 11, and the heat treatment 18, and the fuel and electricity cost of the burner can be saved.

[0014]

As described above, according to the present invention, the power for supplying power to the melting furnace is supplied from the cogeneration power source that generates waste heat, so that stable power can be secured and incineration is possible. The efficiency of ash treatment is improved. Further, in such a configuration, the efficiency of the incineration ash melting system is further improved by using the exhaust heat as the heat source for the drying process.

Further, in such a structure, the exhaust heat is reduced to 2
By providing the heat source for the secondary combustion treatment, the efficiency of the incineration ash melting system is further improved.
Further, in such a structure, by using the exhaust heat as a heat source for heat treatment, the efficiency of the incineration ash melting system is further improved. Further, in such a configuration, by providing the cogeneration power source with a further auxiliary heat source, heat can be supplied from the auxiliary heat source when exhaust heat from the cogeneration power source is insufficient, and the burner fuel can be supplied. It is possible to save electricity and electricity costs more than before.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an incineration ash melting system according to an embodiment of the present invention.

FIG. 2 is a block diagram showing the configuration of a conventional incineration ash melting system.

[Explanation of symbols]

1: Incinerator ash, 2: Drying process, 5: Melting furnace, 10: Exhaust gas, 11: Secondary combustion process, 15: Molten slag, 18: Heat treatment, 25: Cogeneration power source

Claims (5)

[Claims] 1. An incinerator ash is dried and then melted in a melting furnace, and exhaust gas generated in the melting furnace is discharged after being subjected to secondary combustion processing, and molten slag generated in the melting furnace is generated. In an incinerator ash melting system in which a heat treatment for crystallization is performed after crushing, an incinerator ash melting system characterized in that a power supply for supplying power to the melting furnace is supplied from a cogeneration power source that generates exhaust heat. 2. The incinerator ash melting system according to claim 1, wherein the exhaust heat is used as a heat source for the drying process. 3. The incinerator ash melting system according to claim 1, wherein the exhaust heat is used as a heat source for the secondary combustion treatment. 4. The incinerator ash melting system according to any one of claims 1 to 3, wherein the exhaust heat is used as a heat source for the heat treatment. 5. The incinerator ash melting system according to claim 1, wherein the cogeneration power source is provided with a further auxiliary heat source.