JP3595321B2 - Purification method of dioxins from waste incineration plant - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to demolition of general household garbage and industrial garbage waste incineration facilities, and purification of dioxins from incineration facility adhering substances discharged from facilities such as waste incinerators discharged during renovation. is there.
[0002]
[Prior art]
When household waste and industrial waste waste incineration facilities are used for a long time, combustion residues adhere to the waste incinerator and attached facilities, and these deposits contain dioxins. There are many. When dismantling or renovating an aging waste incineration facility, take care not to discharge dioxins to the outside, remove these deposits, and apply high-pressure water to the waste incinerator. Although the details have been removed, since water is used, the removed deposits are muddy.
Since this mud contains dioxins, it cannot be dismantled or treated at renovation sites, and no effective treatment method for dioxins has been established. Although they are buried or buried, they are currently confused about the processing.
[0003]
[Problems to be solved by the invention]
As mentioned above, in addition to being confused about the treatment of discharged deposits, environmental standards for dioxins have become stricter in recent years, and the Dioxin Special Measures Measures Law revised in January 2000 The emission standard for waste incinerators was changed from December 1, 2002, and the value of 80 ng-TEQ / mN was changed from 1 ng-TEQ / mN for facilities with incineration capacity of 4 tons / hour or more. In a facility having an incineration capacity of mN, 2 to 4 tons / hour, it has been decided to regulate to 5 ng-TEQ / mN.
For this reason, many of the waste incineration facilities that have been used up to now cannot adhere to environmental standards.To satisfy new environmental standards, it is necessary to construct new waste incineration facilities equipped with new technologies. It is necessary to carry out renovation work to equip efficient equipment.
[0004]
However, when constructing a new waste incineration facility, it is expected that it will be difficult to obtain the approval of the residents of the new location even if an attempt is made to construct one in a new location. Will be newly established. In addition, even in the case of renovation work, it is necessary to remove the deposits inside the waste incinerator etc. before starting the work.
For this reason, when dismantling, in order to prevent dioxins from escaping to the outside, it is necessary to remove debris such as waste incinerators and then disassemble it. Unless it is removed, the process cannot proceed to the next step.
In particular, since there is a possibility that the amount of the adhered matter removed and recovered in the future will be large, it has been an issue in the industry how to treat and detoxify the matter.
[0005]
[Means for Solving the Problems]
The present invention chemically treats mud-like dioxins discharged together with water for cleaning when dismantling or renovating a waste incineration facility, and in particular, stirs muddy matter of attached matter. Meanwhile, a Raney nickel solution activated with an alkaline solution and hydrogen are added thereto to reduce dioxins and render them harmless.
The supply of the Raney nickel liquid and hydrogen to the slurry is performed by separately inserting the slurry from the inside and outside of the double-pipe structure pipe while stirring the slurry.
Further, when the muddy body added with the Raney nickel liquid and the hydrogen and agitated exhibits alkalinity, the Raney nickel liquid and the muddy body are continuously stirred without adding the hydrogen to thereby obtain the Raney nickel. Dioxins can be reduced without supplying a liquid and hydrogen.
At this time, the addition of the Raney nickel liquid is stopped, but the stirring of the slurry can be continued while hydrogen is continuously added.
Further, since Raney nickel used is in a powder state similar to flour, it can be easily mixed or dispersed.
[0006]
Embodiment
Adherents containing harmful substances such as dioxins are adhered to the facilities such as waste incinerators. A cover is provided so as not to be scattered outside, or the waste incineration facility itself is put in a negative pressure state, and thereafter, the adhered substance inside is removed.
In the operation of removing the adhering matter, usually, the adhering matter inside the waste incineration facility is dropped using a hanging tool or a device, and then high-pressure water is used to remove details. For this reason, the attached matter is in a mixed state of a mud state mixed with water and a solid state. At the dismantling or repairing site of a waste incineration facility, such a state is stored in a drum or the like, and is carried out to the outside.
[0007]
FIGS. 1 and 2 show that the mud state of the deposits stored in the drum 1 is treated by the method of the present invention. As shown in FIG. 1, a Raney nickel solution and hydrogen activated with an alkaline aqueous solution are added to a mud state material in a drum 1 while stirring with a stirrer 2 having blades on the outer periphery. The supply of hydrogen and the activated Raney nickel liquid is performed through the inner tube and the outer tube of the supply tube 3 having a double tube structure, respectively. These stirring bodies 2 and the supply pipe 3 having a double pipe structure for supplying hydrogen and the activated Raney nickel liquid may be formed separately, or may be integrated as shown in FIG. As the stirring body 2 as shown in FIG. 1, a commercially available one for civil engineering work sites can be purchased, and the double pipe type insertion supply pipe 3 only needs to be concentric. Since they can be easily assembled, they can be processed in one corner of the demolition site.
[0008]
FIG. 3 is a schematic diagram showing a case in which a mud state is treated in a concrete frame 4 that has been treated with plastic or the like so that moisture does not leak. Hydrogen and activated Raney nickel liquid are supplied to the mud state in the concrete frame 4 using the deep mixing device 5. In FIG. 3, the concrete frame 4 is installed in the ground, but the invention is not limited to this. When it is carried out on the ground, it may be a steel box which does not leak moisture. The mud state material after the treatment is carried out by a vacuum device, a shovel car, or the like.
Further, since the mud state material after the treatment has a large amount of water, it can be separated into a solid and a liquid by filtration. At this time, if a filter that does not allow Raney nickel to pass through is used, only water can be discharged without releasing Raney nickel to the outside.
[0009]
FIG. 4 shows an example of an apparatus for processing a mud state object in the state shown in FIG. This device is called a deep mixing device, and is used for civil engineering ground improvement work and the like. When the deep mixing device 5 is used, the mud-state material is processed while rotating the rotating rod 6 while ejecting Raney nickel liquid from the tip discharge port 7 and ejecting hydrogen from the side face ejection port 8. Will be.
[0010]
FIG. 5 is not a case where the mud-state material is treated in the concrete frame as shown in FIG. 3, but a mud-state material in a tank 9 provided on a bed of a sludge transport vehicle or the like having a structure in which water does not leak. Is schematically shown. The hydrogen and the activated Raney nickel liquid container 10 may be installed between the driver's seat and the loading platform. FIG. 5 does not show a stirring device, but uses the device used in FIGS. do it.
FIG. 6 shows that the concrete mixer truck 11 may be used as a mud-state material treatment device. Since the concrete mixer can rotate the mud-state material inserted therein, there is no need to attach a stirrer, and it is only necessary to install the pipe-shaped body 12 for supplying Raney nickel liquid and hydrogen.
[0011]
The method of processing on the vehicle body as shown in FIGS. 5 and 6 can be carried out at one corner of a dismantling or repair site, and the drum shown in FIGS. 1 and 2 can also be processed on the vehicle body such as a truck. In this case, since it can be handled in the same manner as general muddy matter generated at a construction site, there is no toss in searching for a disposal site for muddy matter.
[0012]
Also, in the above description, the Raney nickel liquid and the hydrogen added with the alkaline aqueous solution were added while stirring the mud-state material, but the mud-like material was sampled during the stirring, and the mud-state material exhibited alkalinity. In this case, the dioxins can be reduced without supplying the Raney nickel liquid and hydrogen by continuing to stir the slurry without adding the Raney nickel liquid and hydrogen.
At this time, the addition of the Raney nickel liquid is stopped, but the stirring of the slurry can be continued while hydrogen is continuously added.
This is probably because the liquid is in a mud state, and due to the pressure of the mud state, considerable hydrogen is trapped in the mud state and the purification action by Raney nickel is continuing, and only hydrogen is removed. The reason why the purifying action continues even after the addition is that the activation of Raney nickel continues while the mud state liquid is alkaline, and the purifying action may be continued by the addition of hydrogen. Seem.
[0013]
Raney nickel used in the present invention refers to nickel metal that is commonly used as a catalyst in the field of chemistry when reducing chemical substances with hydrogen. As it is called a catalyst, it is a substance that does not participate in any chemical reaction.However, once it is brought into contact with a dilute alkaline solution, or when it is reduced with hydrogen in a state mixed with the alkaline solution, In the field of chemistry, Raney nickel treated with an alkaline solution is referred to as activated Raney nickel because of its good hydrogen reducing action.
Raney nickel used in the present invention, as described above, is used only as a catalyst, and will remain as it is in the mud after use, but since nickel is a stable metal, The state will be maintained as it is in the soil.
[0014]
【The invention's effect】
According to the present invention, general household garbage and industrial garbage can be easily removed from incinerators containing dioxins generated at the time of dismantling and repair of waste incineration facilities, so even if environmental standards become strict, Dioxins contained in incinerator deposits can be easily treated without any difficulty in dismantling or renovating the waste incineration facility.
[Brief description of the drawings]
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an embodiment of the present invention in which a mud state of an adhering substance stored in a drum can is treated by the method of the present invention. It is the perspective view provided in the body.
FIG. 2 is a view showing that the mud state of the deposits stored in the drum can is treated by the method of the present invention in the embodiment of the present invention. It is the perspective view which provided integrally.
FIG. 3 is a schematic view showing that a mud state in a concrete frame is treated by the method of the present invention in the embodiment of the present invention.
FIG. 4 is a side view showing a deep mixing apparatus for treating a mud-state material in the embodiment of the present invention.
FIG. 5 is a schematic view showing that a mud state is treated by a method of the present invention in a tank provided on a cargo bed of a car in the embodiment of the present invention.
FIG. 6 is a schematic diagram showing that a mud state is treated by the method of the present invention in a mixer of a concrete mixer truck in the embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Drum can 2 Stirrer 3 Supply pipe of double pipe structure 4 Concrete frame 5 Deep mixing device 6 Rotating rod 7 Tip discharge port 8 Side injection port 9 Tank 10 Container 11 Concrete mixer truck 12 Pipe-shaped body

Claims (6)

When dismantling or renovating a waste incineration facility, solids and muddy liquid from the incinerator and other facilities that accumulate dioxins and other dioxin-containing deposits that are discharged together with cleaning water are collected. While being stirred, Raney nickel solution activated with an aqueous alkali solution and hydrogen were added to the dioxins to reduce and detoxify the dioxins, which were discharged from a waste incineration facility. A method for purifying dioxins from incineration plant deposits. The waste according to claim 1, wherein the solid matter or the muddy liquid of the deposit is accumulated in a movable storage body disposed near a waste incineration facility, and detoxified on the spot. A method for purifying dioxins from incineration plant deposits discharged from incineration plants. 3. When the muddy liquid under stirring exhibits alkalinity, stirring of the muddy liquid is continued as it is without adding the Raney nickel liquid and hydrogen. Of dioxins from incineration plant deposits discharged from waste incineration plants in Japan. When the muddy liquid under stirring is alkaline, the addition of the Raney nickel liquid is stopped, but the stirring of the muddy liquid is continued while the addition of hydrogen is continued. Item 4. The method for purifying dioxins from incineration plant adhering matter discharged from a waste incineration plant according to item 1 or 2. 2. The method according to claim 1, wherein the Raney nickel and hydrogen are added to the mud by separately inserting the mud from the inside and the outside of the double-pipe pipe while stirring the mud. 5. The method for purifying dioxins from incineration plant deposits discharged from a waste incineration plant according to any one of claims 4 to 4. The method for purifying dioxins from incineration plant deposits discharged from a waste incineration plant according to any one of claims 1 to 5, wherein the Raney nickel is in a powder state.

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