JPS6038079A - Method and equipment for high temperature melting treatment of waste material - Google Patents

Abstract

PURPOSE:To reduce an energy consumption amount, by using a used reactant used in a noxious gas removing apparatus for purifying exhaust gas as the m.p. falling agent of the incineration residue in a high temp. furnace. CONSTITUTION:Hight temp. exhaust gas generated from an incinerator 11 is cooled after introduced into an exhaust gas boiler 12 and discharged to a noxious gas removing apparatus 14 while minute ash floated in the exhaust gas is collected by an electric dust collector 13. Quick lime 17 is separately charged into this apparatus 14 and the reaction product formed to the outer skin part of quick lime 17 by the passage of the exhaust gas is charged into a separator 15 along with quick lime 17 to separate the surface reaction product from quick lime. On the other hand, the incineration residue from the incinerator 11 or incineration ash from the exhaust gas boiler 2 is preliminarily charged in a high temp. melting furnace 16 and, when quick lime 17 from the separator 17 is charged in said furnace 16, the m.p. of the molten substance therein is fallen and the melting of the incineration residue is enabled in reduced quantity of electricity or a reduced oil amount.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a method for high-temperature melting treatment of waste and its equipment, and in detail 1. The present invention relates to a high-temperature melting method and equipment for facilitating the melting of incineration residue in a high VIJL melting furnace. This is used in the field of reducing the amount of energy consumed for melting the residue when incineration residue is turned into molten slag to reduce and stabilize its volume.

(b) Prior art An example of an incinerator for incinerating waste such as municipal garbage is shown in Figure 1, which includes an incinerator 1, a heat recovery boiler 2 using incineration exhaust gas, and a heat recovery boiler 2 that captures minute incineration ash in the exhaust gas. from an electrostatic precipitator 3 that collects the dust, a harmful gas removal device 4 that removes harmful gases from exhaust gas, and a high-temperature melting furnace 5 that melts incineration residue discharged from the incinerator 1 and incinerated ash that has settled in the heat recovery boiler 2. Thus, the exhaust gas discharged from the incinerator 1 and the incineration residue can be smoothly processed within one facility. The high-temperature melting furnace 5 has the function of melting, reducing and stabilizing the incineration residue in order to dispose of it or utilize it.

In addition to ash, incineration residue contains unburnt materials such as metals and ceramics, and its melting temperature is generally about 1500°C. Therefore, in order to melt the incineration residue at room temperature or around 100°C, which is fed into the high-temperature melting furnace 5, a large amount of energy such as electricity or oil is consumed by the electrical resistance method, oil bar method, microwave method, etc. There is. Since this energy is used only for processing the incineration residue, it is better to use as little as possible, and as a measure to achieve this, quicklime, which has the effect of lowering the melting temperature of the incineration residue, is separately charged into the high-temperature melting furnace 5. There is. However, the amount of quicklime added reaches approximately 30% by weight of the incineration residue. On the other hand, in harmful gas removal devices, quicklime is still used to remove sulfur and chlorine from exhaust gas. As a result, a large amount of quicklime is consumed in waste treatment, and the amount of reaction products generated by harmful gas removal equipment and molten slag obtained from high-temperature melting furnaces increases. The amount of waste being discarded is increasing, and there is a strong demand for improvement.

(C) Purpose of the invention The present invention has been made to solve the above-mentioned problems.
We aim to reduce the amount of quicklime used as a melting point depressant for incineration residue in the high-temperature melting furnace used in one waste treatment facility, and the amount of quicklime used as a harmful gas removal agent in the harmful gas removal equipment. It is an object of the present invention to provide a method for high-temperature melting treatment of waste and its equipment, which can reduce the total amount of molten slag from a furnace and the amount of reaction products discharged from a harmful gas removal device.

(()) Structure of the Invention The structure of the present invention will be explained based on FIG. The quicklime 17 used as a reactant in the dry harmful gas removal device 14 to purify the exhaust gas from the incinerator 11 is charged into the high-temperature melting furnace 16, and the waste is melted at high temperature to be used as a melting point depressant for the incineration residue. This is a processing method.

The second invention is a waste treatment facility that processes incineration residue after incinerating waste at a high temperature by melting and solidifying the incinerator 11.
Quicklime 17 as a reactant to purify exhaust gas from
A 11lt machine 15 is provided between the dry harmful gas removal device 14 into which the waste is charged and the high-temperature melting furnace 16 which melts the incineration residue. This is a high-temperature melting treatment facility for waste.

(e) Examples Hereinafter, the present invention will be explained with reference to drawings showing examples thereof.

Figure 2 is an overall layout diagram of the waste treatment equipment 10, where 11 is an incinerator for incinerating waste such as municipal garbage, and 12 is an incinerator 1.
j3 is an electrostatic precipitator that collects minute ash in the exhaust gas that has passed through the exhaust gas boiler 12; Dry harmful gas removal device for removing sulfur, chlorine, etc. using quicklime, 15
is a separator for recovering quicklime from the reaction product obtained by the reaction in the harmful gas removal device 14, and is, for example, a ball mill. The quicklime fed into the harmful gas removal device 14 is granular, and reaction products such as calcium sulfate are generated on the surface of the quicklime, and the quicklime remains unreacted inside, so this separation is difficult. The machine 15 has a function of mechanically collecting it. 16 is a high-temperature melting furnace, which contains incineration residue from the incinerator 1 and an exhaust gas boiler 12;
Incineration ash that has settled inside the reactor is input and melted to produce molten slag. In addition, this high-temperature melting furnace 1
Quicklime from the separator 15 is fed as a melting point depressant to lower the melting temperature of the incineration residue etc. in the separator 15.

According to the waste treatment equipment configured as described above, it is possible to treat the exhaust gas and incineration residue generated from the incinerator in the following manner, and also to remove harmful components and reduce the volume when disposing of them. Stabilization can be achieved with small amounts of reactants and energy.

First, since the exhaust gas generated from the incinerator 11 has high-temperature thermal energy, it is introduced into the exhaust gas boiler 12 to recover heat. The exhaust gas that has passed there and cooled down has minute ash particles floating therein collected by the electrostatic precipitator j3, and is led out to the harmful gas removal device 14. [Harmful gas removal device] In 4, quicklime 17 is separately put into a pair of louis (not shown) through which the exhaust gas flows, so as the exhaust gas flows through the gaps, it reacts and produces calcium sulfate and chloride. Calcium is produced as a reaction product, which removes sulfur and chlorine from the exhaust gas and releases it into the atmosphere. These reaction products are mainly produced in the outer skin of the granular quicklime, so this is fed into the separator 15 and rotated with a steel pole, for example, so that the reaction products on the surface are crushed or peeled off from the periphery of the quicklime. Quicklime, which is similar to the original reactant, is separated. The reaction product is almost powder-like, and when sieved, quicklime with small particles is obtained. On the other hand, since the incineration residue from the incinerator 11 and/or the incineration ash from the exhaust gas boiler 12 are charged into the high-temperature melting furnace 16, the quicklime from the portion 11lltta 15 is supplied therein. The melting point of incineration residue varies depending on the type of garbage, but is usually around 1,500°C, and when quicklime 17 is added, the viscosity of the molten material decreases due to the quicklime with high conductivity, and the melting point drops to, for example, around 1,300°C. do. As a result, incineration residue can be melted with less electricity and oil,
Incineration residue can be easily converted into molten slag.

In addition, since quicklime 17 is charged into the high-temperature melting furnace 16, the gas generated in the high-temperature melting furnace 16 is mostly air and water vapor, except for a small amount of carbon monoxide caused by the combustion of unburned materials. , does not contain large amounts of harmful gas components. As a result, the gas is supplied to the low-temperature side of the exhaust gas boiler 12, for example, and the heat is recovered, but the reaction product is generated in the quicklime charged in the harmful gas removal device 14 more than before, and the separator 15 There is no reduction in the amount of quicklime separated and recovered.

Calcium sulfate and calcium chloride separated in the separator 15 are dumped in solid or powdered form, and the molten slag obtained in the high-temperature melting furnace 16 is dumped in a landfill or the like.
Used as an auxiliary material for other industries.

However, if at least calcium is supplied to the high-temperature melting furnace 16, the above-mentioned effect can be achieved, but if the reaction product containing quicklime from the harmful gas removal device 14 is directly supplied. It's okay. However, in that case, the sulfur and chlorine content in the reaction product will vaporize again in the high-temperature melting furnace 1G and harmful gases will be generated, so wet gas treatment using caustic soda or the like is used in the high-temperature melting furnace 16. It is necessary to install a dry gas treatment device using quicklime, or a semi-dry gas treatment device using slaked lime. In that case, the separator 15 described above becomes unnecessary, but it is necessary to supply a new reactant for gas treatment in the high temperature melting furnace 16, and in the present invention, such a reactant as well as other melting point depressants are used. It is possible to perform a series of treatments using only the quicklime supplied to the hazardous gas removal device 14, thereby reducing the running costs for removing hazardous gas and melting incineration residue in waste treatment. It is possible to reduce the

(f) Effects of the Invention As explained in detail above, in the first invention, the used reactant used in a harmful gas removal device for purifying exhaust gas is melted in a high-temperature melting furnace at the melting point of the incineration residue. Since the reactant is used as a depressant, the amount of used reactant discarded from the harmful gas removal device is reduced, and the amount of discarded reactant can be reduced. The remaining reactant recovered without being dumped can lower the melting temperature of the incineration residue, making it possible to reduce energy consumption such as electricity or oil in the high-temperature melting furnace. . Furthermore, according to the configuration of the second invention, quicklime can be easily recovered from the reaction product from the harmful gas removal device and supplied to the high-temperature melting furnace. It is possible to achieve this goal.

[Brief explanation of the drawing]

FIG. 1 is a layout diagram of conventional waste treatment equipment, and FIG. 2 is a layout diagram of waste treatment equipment including the waste high temperature melting treatment equipment of the present invention. 10-・Waste treatment equipment, 11-・-Incinerator, 14・-
Harmful gas removal equipment, 15-minute 11llt machine, 16-high temperature melting furnace, 17--quicklime patent applicant Kawasaki Heavy Industries, Ltd.

Claims (3)

[Claims] (1) In a waste treatment facility that processes the incineration residue after incinerating waste at a high temperature, the quicklime used as a reaction agent in a dry harmful gas removal device is used to purify the exhaust gas from the incinerator. A high-temperature melting treatment method for waste, which is characterized by charging waste into a high-temperature melting furnace and using it as a melting point depressant for incineration residue. (2) In a waste treatment facility that processes the incineration residue after incinerating waste at high temperatures, it is a dry type harmful gas removal device in which quicklime is added as a reactant to purify the exhaust gas from the incinerator. A high-temperature melting treatment facility for waste, characterized in that a separator is provided between a high-temperature melting furnace for melting incineration residue and a separator for extracting residual quicklime from the reaction product in the quicklime noxious gas removal device. (3) The high-temperature melting treatment equipment for waste according to claim 2, wherein the separator is a ball mill.