JPH11197625A - Apparatus for making burned ash and fly ash harmless - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize and simplify an apparatus and to reduce initial costs and running costs by separating combustion gas for heating, burned ash, and fly ash without generation of heavy metals, chlorides, dioxin, and others with combustion gas. SOLUTION: A closed container 9 which charges an additive for generating burned ash, fly ash, and chlorine-containing gas and prevents contact with outside air, a heating furnace 3 surrounding the container 9, a combustion apparatus 11 installed on the side wall of the furnace 3 to heat the container 9 in the furnace 3, a duct 15 which connects the container 9 to one end to make the pressure of the container 9 negative, and a negative pressure device 17 connected to the other end of the duct 15 are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for detoxifying incinerated ash and fly ash, which removes heavy metals contained in incinerated ash and fly ash remaining after burning in an incinerator and renders it harmless. .

[0002]

2. Description of the Related Art Combustible materials are incinerated in incinerators or converted to solid fuel and incinerated in incinerators due to the increase in the amount of industrial waste and waste generated from ordinary life due to the increase in the amount of waste and the tightness of landfill sites. The volume has been reduced and the volume has been reduced. On the other hand, environmental pollution caused by the burning of wastes has become a social problem, and devices that comply with environmental standards have been installed.

[0003] When the waste is burned in the incinerator, incineration ash containing heavy metals is generated from the incinerator, and slaked lime or the like is carried on fly ash also contained in the combustion gas for heating and collected by a bag filter. Is done. Heavy metals contained in the generated incineration ash and fly ash require strict management for environmental hygiene. In order to remove heavy metals, incineration ash and fly ash are usually melted at a high temperature of 1350 ° C. or more to form a slag, or heated to 650 ° C. or more and 1200 ° C. or less to contain calcium chloride and fly ash. There is known a method of volatilizing and recovering chlorides of heavy metals by contact reaction with a heavy metal compound.

[0004] As an apparatus for actually performing these methods, conventionally, incinerated ash and fly ash are heated in a ventilated atmosphere using a heating burner or plasma to remove heavy metals.

[0005]

By the way, in the above-mentioned conventional apparatus, a harmful gas is generated together with the combustion gas for heating, so that an increase in the amount of processing increases the size and complexity of the apparatus itself. In addition, there is a problem that the running cost increases.

An object of the present invention is to separate a combustion gas for heating from incinerated ash and fly ash without generating heavy metals, chlorides, dioxins and the like together with the combustion gas for heating, thereby making it possible to provide an apparatus of the present invention. It is an object of the present invention to provide a detoxifying apparatus for incinerated ash and fly ash which can be reduced in size and simplified, and has reduced initial costs and running costs.

[0007]

In order to achieve the above object, a detoxifying apparatus for incinerated ash and fly ash according to the present invention according to claim 1 is an additive for generating incinerated ash and fly ash and chlorine-based gas. A sealed container into which an object is charged and kept out of contact with outside air, a heating furnace surrounding the sealed container, a combustion device provided on a side wall of the heating furnace for heating the sealed container in the heating furnace, and the closed container It is characterized by comprising a duct for connecting one end to a closed container to make the inside a negative pressure, and a negative pressure device connected to the other end of the duct.

Therefore, when an additive for generating incineration ash, fly ash and chlorine-based gas is charged into the closed vessel, and then the combustion device is operated to supply the combustion gas into the heating furnace, the inside of the heating furnace is sealed. The container is heated. As a result, the combustion gas is discharged from the heating furnace to the outside,
The heavy metals contained in the fly ash chemically react with the additive and are discharged to the outside from the duct by a negative pressure device together with the chloride.

Since the incineration ash and fly ash are not directly heated by the combustion device, heavy metals, chlorides, dioxins, etc., generated from the incineration ash and fly ash are not generated together with the combustion gas, and are used for heating. By separating the combustion gas from the incineration ash and fly ash, the size and size of the apparatus can be reduced, and the initial cost and running cost can be reduced.

[0010] Further, by applying a negative pressure to the inside of the closed container, chlorides from the incinerated ash and fly ash are easily volatilized, and the removal efficiency is improved.

According to a second aspect of the present invention, there is provided a detoxifying apparatus for incinerated ash and fly ash according to the present invention. Outside the closed container and / or
Or a heating means for heating the inside, a duct connecting one end to the closed vessel to make the inside of the closed vessel a negative pressure, and a negative pressure device connected to the duct. is there.

Therefore, after the incineration ash, fly ash and additives are charged into the closed container, the outside and / or inside of the closed container is heated by the heating means. As a result, the combustion gas for heating is not generated, and the heavy metals contained in the incineration ash and fly ash chemically react with the additive and are discharged to the outside from the duct together with the chloride by the negative pressure device.

Thus, the same operation as in the first aspect is performed. By using a heating means other than the combustion device, no combustion gas for heating is generated, so that secondary pollution does not occur and the size and simplification of the device can be further reduced.

According to a third aspect of the present invention, there is provided a detoxifying apparatus for incinerated ash and fly ash according to the present invention. A closed container having a double structure of the outer container, a heating means for heating the outer container of the closed container, a duct connecting one end to the inner container to make the inner container of the closed container a negative pressure, and And a negative pressure device connected to the end.

Accordingly, when the incineration ash, fly ash and additives are charged into the inner container of the closed container and the outer container of the closed container is heated by the heating means, the heat of the outer container is transmitted to the inner container and heated. You. As a result, the heavy metals contained in the incineration ash and fly ash are discharged to the outside from the duct together with the chloride by a negative pressure device together with the chloride without generating the combustion gas for heating.

Thus, the same operation as in claim 2 is performed. In addition, since the inner container is made of metal and the outer container is made of ceramic, and the inner container and the outer container are made of metal, the running cost can be reduced by replacing only short-lived metals.

According to a fourth aspect of the present invention, there is provided the detoxifying apparatus for incinerated ash and fly ash according to the first, second or third aspect, wherein the negative pressure in the duct is monitored. And a pressure sensor provided via a pipe in the middle of the duct to adjust the negative pressure device to a constant negative pressure by the signal and convert the pressure into an electric signal. Is what you do.

Therefore, since the pressure in the duct is detected by the pressure sensor, the negative pressure device is adjusted on the basis of the detected pressure to keep the negative pressure in the closed vessel constant, so that the chloride volatilization efficiency can be improved. And the running cost of the negative pressure device is reduced.

According to a fifth aspect of the present invention, there is provided a detoxifying apparatus for incinerated ash and fly ash according to the present invention.
In the apparatus for detoxifying fly ash, one end of an air purge pipe is communicated with the closed vessel to agitate the incinerated ash and fly ash and additives in the closed vessel, and an air compressor is provided at the other end of the air purge pipe. It is characterized by being provided.

Therefore, when the air compressor is operated,
Air is supplied from the air purge pipe into the closed container, and the incinerated ash and fly ash charged in the closed container are stirred, so that particles of the incinerated ash and fly ash during heating do not form a layer.
It is evenly contacted with additives that extract heavy metals. Thus, since there is no mechanical element, there is no failure and maintenance costs are reduced.

The detoxifying apparatus for incinerated ash and fly ash according to the present invention according to claim 6 is the detoxifying apparatus for incinerated ash and fly ash according to claim 1, 2, 3 or 4 in the middle of the duct. In addition, a wet dust collector, a moisture removing device, and a bag filter are provided in series from the closed container side.

Therefore, the generation of dioxin is suppressed by reducing the temperature of the exhaust gas by the wet dust collector, the chloride is removed, the temperature of the bag filter is controlled, and the filter cloth is prevented from being clogged by the moisture removing device.

According to a seventh aspect of the present invention, there is provided the detoxifying apparatus for incinerated ash and fly ash according to the sixth aspect of the present invention, wherein the duct between the moisture removing apparatus and the bag filter is provided. The apparatus is characterized in that a charging device for an alkaline earth metal object is provided via a pipe so that the alkaline earth metal object can be injected on the way.

Therefore, when the alkaline earth metal object is introduced into the duct from the alkaline earth metal object introduction device via the pipe, the alkaline earth metal object chemically reacts with excess chlorine and is collected.

[0025]

Embodiments of the present invention will be described below in detail with reference to the drawings.

Referring to FIG. 1, a detoxifying apparatus 1 for incinerated ash and fly ash is provided with a heating furnace 3 made of a heat-resistant tile or the like, and a substantially central portion of an upper frame 3U of the heating furnace 3 is opened and closed. A free door 5 is provided.
Is provided on the lower frame 3D of the
A closed container 9 into which an additive for generating incineration ash, fly ash, and chlorine-based gas is placed from an openable and closable door 5 is placed. That is, the heating furnace 3 is in a state surrounding the closed container 9.

The heating furnace 3 shown in FIG.
A combustion device 11 is attached to the lower side of R. Further, a chimney 13 is attached to the upper part of the left frame 3L in FIG. One end of the duct 15 is connected to the upper part of the closed vessel 9 in the heating furnace 3 from the openable door 5 of the upper frame 3U in the heating furnace 3 and the other end of the duct 15 is connected to a vacuum pump, an exhaust device. Is connected.

In the middle of the duct 15, a wet dust collector 19, a water removing device 21 and a bag filter 23 are provided in series from the closed container 9 side. A pressure sensor 27 is provided via a pipe 25 in the middle of the duct 15 connecting the closed container 9 and the wet dust collector 19. The pressure sensor 27 is electrically connected so that, for example, the rotation speed of the negative pressure device 17 can be adjusted. The connection may be made electrically so as to adjust the opening degree of the damper instead of the rotation speed of the negative pressure device 17.

The air purging pipe 2 is provided in the closed vessel 9.
One end of 9 is connected through the door 5 and the other end of the air purge pipe 29 is connected to the air compressor 31. In the middle of the air purge pipe 29, an automatic opening / closing valve 3 is provided.
3 are provided. An alkaline earth metal material charging device 37 is provided in the middle of the duct 15 connecting the moisture removing device 21 and the bag filter 27 via a pipe 35. A chimney 41 is connected to the negative pressure device 17 via a pipe 39.

With the above configuration, when the combustion device 11 is operated, the heating combustion gas is supplied into the heating furnace 3 to heat the closed vessel 9. This closed container 9 is, for example, 600 ° C.
It is heated to the range of ~ 1200 ° C. And
Air is supplied from the air compressor 29 to the air purge pipe 29 while the additive for generating the incineration ash, fly ash, and chlorine-based gas charged in the closed vessel 9 is supplied to the air purge pipe 29, and the on-off valve is opened. 33 is turned on and off intermittently,
It is sent into the closed container 9. As a result, the incineration ash, fly ash and additives in the closed container 9 are well stirred.

After the combustion gas supplied to the heating furnace 3 is heated in the closed vessel 9, the combustion gas is discharged to the outside from the chimney 15. The incineration ash, fly ash and additives in the closed vessel 9 are heated and the negative pressure device 17 is operated to cause a chemical reaction. That is, the heavy metals contained in the incineration ash and fly ash chemically react with the additive to volatilize the chloride of the heavy metal and are discharged to the duct 15. The heavy metal chloride discharged into the duct 15 is collected by a wet dust collector 19 and then collected by a bag filter 23 via a moisture removing device 21. Ca (OH) ₂ + 2HCl → CaCl ₂ + 2H by introducing slaked lime into the duct 15 through the pipe 35 from the alkali earth metal material feeding device 37.
_It reacts as ₂ O and excess chlorine is often carried as chloride on the bag filter 23. Then, the exhaust gas is discharged from the chimney 41 to the outside via the pipe 39. The incinerated ash and fly ash remaining in the closed container 9 become ash containing no heavy metals, and can be disposed of without any trouble in landfill.

Since the incineration ash and fly ash are not directly heated by the combustion device, heavy metals, chlorides, dioxins, etc. generated from the incineration ash and fly ash are not generated together with the heating combustion gas. By separating the incineration ash and fly ash from the combustion gas for heating, it is possible to reduce the size and simplification of the apparatus and to reduce the initial cost and running cost. In addition, closed container 9
By applying a negative pressure to the inside, chlorides from incinerated ash and fly ash can be easily volatilized, and the removal efficiency can be improved.

Since the pressure in the duct 15 is detected by the pressure sensor 27, the pressure in the negative pressure device 17 is determined based on the detected pressure.
For example, by adjusting the number of rotations and keeping the negative pressure in the closed vessel 9 constant, the volatilization efficiency of chloride can be increased and the running cost of the negative pressure device can be reduced.

When the air compressor 31 is operated, air is supplied from the air purging pipe 29 into the closed container 9 and the incinerated ash and fly ash charged in the closed container 9 are agitated. Without particles of incineration ash and fly ash forming a layer,
It is evenly contacted with additives that extract heavy metals. Therefore, since there is no mechanical element, there is no failure and maintenance cost can be reduced.

The reduction of exhaust gas temperature by the wet dust collector 19 suppresses the generation of dioxin, removes chlorides, controls the temperature of the bag filter 23 inlet, and controls the moisture removal device 21.
Clogging of the filter cloth of the bag filter 23 can be prevented.

[0036] For example, slaked lime as an alkaline earth metal material is charged into the duct 15 from the alkaline earth metal material charging device 37 via the pipe 35, so that it is chemically reacted with excess chlorine and collected. it can.

FIG. 2 shows a detoxification apparatus 1 for incinerated ash and fly ash according to another embodiment which is an alternative to FIG. In FIG. 2, the same components as those in FIG. 1 are denoted by the same reference numerals, and redundant description will be omitted.

In FIG. 2, the outer periphery of the closed container 9 is covered with a heat insulating material 43. An inside heater 45 is provided inside the closed container 9 as a heating means, and an outside heater 47 as a heating means is provided outside the closed container 9.
Is provided. These inner and outer heaters 45 and 47
May be induction heating.

With the above configuration, incinerated ash,
After the fly ash and additives are charged, the heater 4 for the inside and outside
At 5, 47, the outside and / or inside of the closed container 9 is heated. As a result, the combustion gas for heating is not generated, and the heavy metals contained in the incineration ash and fly ash chemically react with the additive and are discharged from the duct 15 to the negative pressure device 17 together with the chloride.

Thus, the same operation as in the above-described embodiment,
The effect takes place. Further, by employing the heater 45 for the inside and / or the heater 47 for the outside of the heating means instead of the combustion device, no combustion gas for heating is generated, so that there is no secondary pollution, and the size of the device is further reduced. , Can be simplified.

FIG. 3 shows another embodiment of the heating means for heating the closed container 9 in FIG. FIG.
In FIG. 2, the same components as those in FIG. 2 are denoted by the same reference numerals, and redundant description will be omitted.

In FIG. 3, the closed container 9 is an inner container 9A.
And the outer container 9B. Moreover, the outside of the outer container 9B is covered with a heat insulating material 49. A heater 51 is provided as heating means for heating the outer container 9.

With the above configuration, the inner container 9 of the closed container 9
After the incineration ash, fly ash and additives are put into A, when the outer container 9B of the closed container 9 is heated by the heater 51, the heat of the outer container 9B is transmitted to the inner container 9A and heated. As a result, the heavy metals contained in the incinerated ash and fly ash chemically react with the additives and are discharged from the duct 15 to the negative pressure device 17 together with the chloride without generating the combustion gas for heating. .

Thus, the same operations and effects as in FIG. 2 are performed. Moreover, since the inner container 9A is made of metal and the outer container 9B is made of ceramic, and the inner container 9A and the outer container 9B are made of metal, the running cost can be reduced by replacing only the metal having a short life. it can.
Note that the heater 51 may be induction heating.

The present invention is not limited to the above-described embodiment, but can be embodied in other modes by making appropriate changes.

[0046]

As will be understood from the embodiments of the present invention as described above, according to the first aspect of the present invention, an additive for generating incinerated ash, fly ash and chlorine-based gas is provided in a closed container. After the charging, when the combustion device is operated to supply the combustion gas into the heating furnace, the closed vessel in the heating furnace is heated.
As a result, the combustion gas is discharged to the outside of the heating furnace, and the heavy metals contained in the incineration ash and fly ash are chemically reacted with the additives and discharged from the duct together with the chloride to the negative pressure device.

Since the incinerated ash and fly ash are not directly heated by the combustion device, heavy metals, chlorides, dioxins, etc., generated from the incinerated ash and fly ash are not generated together with the combustion gas, and the ash and fly ash are not heated. By separating the combustion gas from the incineration ash and fly ash, it is possible to reduce the size and simplification of the apparatus and to reduce the initial cost and running cost.

Further, by applying a negative pressure to the inside of the closed container, chlorides from the incinerated ash and fly ash are easily volatilized, and the removal efficiency can be improved.

According to the second aspect of the present invention, after the additives for generating incineration ash, fly ash and chlorine gas are introduced into the closed container, the outside and / or inside of the closed container is heated by the heating means. Is done. As a result, the combustion gas for heating is not generated, and the heavy metals contained in the incineration ash and fly ash chemically react with the additive and are discharged to the outside from the duct together with the chloride by the negative pressure device.

Thus, the same effect as the first aspect can be obtained. Furthermore, since the heating combustion gas is not generated by using the heating means other than the combustion device, secondary pollution does not occur and the size and simplification of the device can be further reduced.

According to the third aspect of the present invention, after the incineration ash, fly ash and additives are charged into the inner container of the closed container, and the outer container of the closed container is heated by the heating means, the heat of the outer container is reduced. Is transferred to the inner container and heated. As a result, the heavy metals contained in the incineration ash and fly ash are discharged to the outside from the duct together with the chloride by a negative pressure device together with the chloride without generating the combustion gas for heating.

Thus, the same effect as the second aspect can be obtained. Moreover, since the inner container is made of metal and the outer container is made of ceramic, and the inner container and the outer container are made of metal, the running cost can be reduced by replacing only the metal having a short life.

According to the fourth aspect of the present invention, since the pressure in the duct is detected by the pressure sensor, the negative pressure device is adjusted based on the detected pressure to make the negative pressure in the closed container constant. Thereby, the chloride volatilization efficiency can be increased and the running cost of the negative pressure device can be reduced.

According to the fifth aspect of the present invention, when the air compressor is operated, air is supplied from the air purge pipe into the closed container, and the incinerated ash and fly ash charged in the closed container are stirred. Therefore, the particles of the incineration ash and fly ash during heating do not form a layer, and are evenly contacted with the additives for extracting heavy metals. Thus, since there is no mechanical element, there is no failure and the maintenance cost can be reduced.

According to the invention, the generation of dioxin is suppressed by reducing the temperature of the exhaust gas by the wet dust collector, the chloride is removed, and the temperature at the inlet of the bag filter is controlled.
The filter cloth can be prevented from clogging of the bag filter by the moisture removing device.

According to the seventh aspect of the present invention, the alkaline earth metal object is introduced into the duct through the pipe from the alkaline earth metal object introduction device, thereby chemically reacting with the excess chlorine and collecting it. be able to.

[Brief description of the drawings]

FIG. 1 is a front view of a detoxifying apparatus for incinerated ash and fly ash according to the present invention.

FIG. 2 is a front view of another incineration ash and fly ash detoxifying apparatus of the present invention.

FIG. 3 is a cross-sectional view of another embodiment in which the closed container in FIG. 2 is heated.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Detoxification apparatus of incineration ash and fly ash 3 Heating furnace 5 Door 9 Airtight container 11 Combustion device 15 Duct 17 Negative pressure device 19 Wet dust collector 21 Moisture removal device 23 Bag filter 27 Pressure sensor 31 Air compressor 37 Alkaline earth metal object Input device

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI B01D 53/26 B01D 53/34 134A 53/68 136Z 53/64 B09B 3/00 ZAB

Claims (7)

[Claims] 1. A closed container which is charged with an additive for generating incinerated ash and fly ash and chlorine-based gas and which is not brought into contact with outside air, a heating furnace surrounding the closed container, and a sealed inside of the heating furnace. A combustion device provided on the side wall of the heating furnace to heat the container, a duct connecting one end to the closed container to make the inside of the closed container a negative pressure, and a negative pressure device connected to the other end of the duct, A detoxification apparatus for incinerated ash and fly ash, comprising: 2. A closed container which is charged with an additive for generating incinerated ash and fly ash and a chlorine-based gas and which is not brought into contact with outside air, heating means for heating the outside and / or inside of the closed container, Detoxification of incinerated ash and fly ash, characterized by comprising a duct connecting one end to the closed container to make the inside of the closed container a negative pressure, and a negative pressure device connected to the other end of the duct. Processing equipment. 3. An airtight container having a double structure of an inner container and an outer container which are charged with an additive for generating incineration ash and fly ash and chlorine-based gas and are not brought into contact with outside air, and an outer side of the airtight container. Heating means for heating the container, a duct connecting one end to the inner container to make the inner container of the closed container a negative pressure, and a negative pressure device connected to the other end of the duct, comprising: Ash and fly ash detoxification equipment. 4. Monitoring the negative pressure in the duct and converting the pressure into an electric signal, and using the signal to adjust the negative pressure device to a constant negative pressure through a pipe in the middle of the duct. The detoxifying apparatus for incinerated ash and fly ash according to claim 1, further comprising a pressure sensor provided. 5. An air purge pipe is connected to one end of an air purge pipe in the closed vessel to stir incineration ash and fly ash and additives in the closed vessel, and an air compressor is provided at the other end of the air purge pipe. Claims 1, 2,
3. The detoxifying apparatus for incinerated ash and fly ash according to 3 or 4. 6. A wet dust collector, a water removing device and a bag filter are provided in series in the middle of the duct from the side of the closed container in order.
Or the detoxifying apparatus for incinerated ash and fly ash according to 5. 7. An alkaline earth metal material input device is provided through a pipe so as to allow an alkaline earth metal material to be injected in the middle of a duct between the moisture removing device and the bag filter. Item 6. A detoxifying apparatus for incinerated ash and fly ash according to Item 6.