JP4361296B2 - Exhaust gas treatment equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an exhaust gas treatment apparatus, and more particularly to an exhaust gas treatment apparatus suitable for a waste incineration facility provided with an ash melting furnace.
[0002]
[Prior art]
In recent years, with regard to waste disposal, reuse (recycling) for protecting the living environment has increased as a social requirement. In addition, with regard to waste that cannot be reused, due to the tightness of the landfill disposal site, the life of the landfill disposal site is extended by incinerating as much as possible the incineration. In addition, incineration facilities are increasingly required to reduce harmful substances discharged from chimneys and to make incineration ash harmless.
As the detoxification reuse of incineration ash, a method is adopted in which incineration ash is melted to suppress elution of harmful substances, taken out as molten slag, and reused for roadbed materials (for example, Patent Document 1). .
[0003]
FIG. 5 is a system diagram of a prior art exhaust gas treatment apparatus.
This exhaust gas treatment apparatus includes an incinerator filtration dust collector 21 for removing dust in the incinerator exhaust gas from the incinerator 1, an incineration ash 14 of the incinerator 1, and the incinerator filtration dust collector 21. An ash melting furnace 8 for melting the collected collected ash 22, an ash melting furnace filter dust collector 10 for removing dust in the melting furnace exhaust gas from the ash melting furnace 8, and the incinerator filter collection It mainly includes a chemical supply pipe 7 that supplies chemicals for removing harmful components in the exhaust gas to the exhaust gas in the upstream of the dust collector 21 and the filter dust collector 10 for the ash melting furnace.
[0004]
In such a configuration, the waste is supplied to the incinerator 1 and incinerated, and the incinerator exhaust gas generated at this time is supplied to the incinerator filtration dust collector 21 through the gas cooling device 2. In the incinerator filtration dust collector 21, dust and solidified harmful components in the incinerator exhaust gas are collected and removed. Since incinerator exhaust gas contains harmful gases such as sulfur oxide and hydrogen chloride, chemicals such as slaked lime are usually supplied from the chemical supply pipe 7 to the incinerator exhaust gas upstream of the incinerator filtration dust collector 21. Then, harmful components in the incinerator exhaust gas react with the chemical to solidify, and are collected as dust ash 22 together with the dust. The processing gas from which the dust and the reactants have been removed is discharged from the chimney 6 through the induction fan 5 to the outside of the system.
[0005]
On the other hand, the collected ash 22 collected by the filter dust collector 21 for the incinerator is supplied to the ash melting furnace 8 and melted together with the incinerated ash 14 of the incinerator 1, and the melt is outside the system as a molten slag 20. To be discharged. The incinerated ash 14 and the collected ash 22 are melted in the ash melting furnace 8 at a high temperature of about 1300 to 1400 ° C., although depending on their components, the harmful components adsorbed on the incinerated ash and the like are molten slag 20 It is not in the form contained therein but is accompanied in the melting furnace exhaust gas discharged from the ash melting furnace 8. Therefore, similarly to the incinerator exhaust gas, the melting furnace exhaust gas after passing through the gas cooling device 9 is harmful because the chemical is introduced from the chemical supply pipe 7 before being introduced into the ash melting furnace filter dust collector 10. The gas is solidified, and the melting furnace processing gas 13 is combined with the incinerator processing gas downstream of the incinerator filtration dust collector 21 by the fan 11 and discharged out of the system. The collected ash collected by the filtration dust collector 10 for the ash melting furnace is not supplied to the ash melting furnace 8 because the toxic gas concentration in the melting furnace exhaust gas gradually increases when it is supplied again to the ash melting furnace 8. Then, the ash is solidified by the cement / chemical 19 and discharged as a final processed product.
[0006]
In the above exhaust gas treatment equipment, harmful gases such as sulfur oxides and hydrogen chloride gas contained in incinerator exhaust gas and melting furnace exhaust gas react with reactive agents such as slaked lime powder to solidify harmful components, and filter for incinerator It is collected and removed by the dust collector 21 and the ash melting furnace filter dust collector 10. This solidification reaction is a so-called solid-gas reaction between a solid drug and a gaseous component, and the reaction is not sufficiently performed only by supplying an equivalent amount of the drug. 5 to 3 times the amount of drug is charged. The unreacted chemical that has been input is collected as the collected ash 17 by the filter dust collector 10 for the ash melting furnace, so the amount of the collected ash 17 increases, and accordingly, the cement There was a problem that the amount of chemicals increased and the cost of final solidification treatment increased. There is also a problem that unreacted drugs cannot be reused and are wasted. Furthermore, since the chemicals are separately fed into the incinerator exhaust gas and the melting furnace exhaust gas, it is not easy to adjust the amount of the chemicals to be introduced, and it is difficult to reduce the amount of the chemicals to be introduced.
[0007]
[Patent Document 1]
JP-A-9-173742 [0008]
[Problems to be solved by the invention]
The problem of the present invention is to solve the above-mentioned problems of the prior art and reduce the amount of chemicals used for removing harmful components in exhaust gas, the amount of cement / chemicals for solidifying collected ash, and the amount of final ash solidified products It is in providing the waste gas processing apparatus which can be made to do.
[0009]
[Means for Solving the Problems]
As a result of intensive studies on the above problems, the inventors of the present invention have installed incinerator filtration dust collectors in two stages, and the collected ash collected by the dust removal filter dust collector in the previous stage is an ash melting furnace. To remove the harmful components from the combined exhaust gas by joining the incinerator exhaust gas between the upstream and downstream filtration dust collectors. In addition, the collected ash collected by the latter-stage harmful gas removal filter dust collector is mixed with the melting furnace exhaust gas upstream of the ash melting furnace filter dust collector. As a result, it has been found that the above-mentioned problems can be achieved, and the present invention has been achieved.
The invention claimed in the present application in order to achieve the above object is as follows.
[0010]
(1) An incinerator filtration dust collector that removes dust in exhaust gas from an incinerator, an ash melt that melts the incineration ash of the incinerator and the collected ash collected by the incinerator filtration dust collector In an exhaust gas treatment apparatus comprising a furnace and a dust collector for ash melting furnace that removes dust in the exhaust gas of the ash melting furnace, the dust collection filtration dust collector as the incinerator filtration dust collector And a means for supplying the collected ash collected by the dust-removing filter dust collector to the ash melting furnace, and the harmful gas-removing filter dust collector. removing harmful gas into the confluence exhaust gas upstream side said to incinerator flue gas ash melting furnace for filtration collecting only setting means for combining the melting furnace process gas from the dust, the harmful gas removal filtration precipitator before flow agent means for introducing provided Rutotomoni for collecting that was collected by the filtration dust collector for harmful gas removal Exhaust gas treatment device characterized by all or part, provided with means for mixing the melting furnace exhaust gas of the ash melting furnace for filtration precipitator previous flow.
[0011]
( 2 ) Incinerator filtration dust collector that removes dust in exhaust gas of incinerator, ash melting that melts incineration ash of the incinerator and the collected ash collected by the incinerator filtration dust collector In an exhaust gas treatment apparatus comprising a furnace and an ash melting furnace filtration dust collector that removes dust in the melting furnace exhaust gas of the ash melting furnace, the filtration filter for dust removal is used as the filtration dust collector for the incinerator A dust collector and a filter for collecting harmful gas are installed in order, and means for supplying the collected ash collected by the dust filter for collecting dust to the ash melting furnace and the filter for collecting harmful gas Means for mixing the collected ash collected by the dust collector with the melting furnace exhaust gas upstream of the ash melting furnace filtration dust collector, and the incinerator exhaust gas upstream of the harmful gas removal filtration dust collector. An exhaust gas treatment apparatus comprising means for introducing a chemical for removing harmful gas.
[0012]
[Action]
In the present invention, as shown in FIG. 1 to be described later, a dust removing filter dust collector 3 and a harmful gas removing filter dust collector 4 are sequentially installed through a duct 12 as a filtration dust collector for an incinerator. The collected ash 15 collected by the dust removing filter dust collector 3 is supplied to the ash melting furnace 8 to be melted, and the dust in the melting furnace exhaust gas is removed by the ash melting furnace filter dust collector 10. The melting furnace treatment gas 13 is merged with the incinerator exhaust gas of the duct 12 and the chemical is supplied from the chemical supply pipe 7 connected to the duct 12 to remove harmful components in the combined exhaust gas. Thus, the medicine can be charged at one place, and the adjustment of the amount of the medicine can be easily performed. As a result, the amount of the medicine can be reduced and the collected ash 17 collected by the filter dust collector 10 for the ash melting furnace can be reduced. Reduction of cement and chemicals 19 necessary for solidification of the collected ash 17 Reduction of and the final solidified product becomes possible.
[0013]
Further, as shown in FIGS. 2 to 4 to be described later, all or a part of the collected ash 16 collected by the harmful gas removal filtration dust collector 4 is moved upstream of the ash melting furnace filtration dust collector 10. By mixing with the melting furnace exhaust gas, the unreacted chemical contained in the collected ash 16 can be reacted with the harmful gas in the melting furnace exhaust gas, and the input chemical can be effectively used. That is, since the reactive agent for removing harmful gas is blown in an amount 1.5 to 3 times the equivalent ratio, the unreacted agent 0.5 to 1.5 times the equivalent ratio is collected ash 16. The collected ash 16 containing such unreacted chemical is blown into the melting furnace exhaust gas upstream of the filter dust collector for the ash melting furnace. Unreacted chemicals can be reacted with harmful gases in the melting furnace exhaust gas, and the charged chemicals can be used effectively. Moreover, since the amount of chemicals for removing harmful gas is reduced, the amount of collected ash 16 and 17 collected by the incinerator filtration dust collector 4 or the ash melting furnace filtration dust collector 10 is reduced. The supply amount of the cement / chemical 19 for solidifying the collected ash 16 and 17 may be small, and the final solidified material amount is also small. Further, the melting furnace treatment gas 13 from which corrosive gases such as sulfur oxides and hydrogen chloride gas in the melting furnace exhaust gas have been removed is joined to the upstream or downstream of the filter dust collector 4 for incinerator, and these are introduced. Corrosion due to corrosive gas such as ducts is prevented.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the drawings, but the present invention is not limited thereto.
FIG. 1 is a system diagram of an exhaust gas treatment apparatus showing an embodiment of the present invention.
1 is different from FIG. 5 in that a dust collector filtration dust collector 3 and a harmful gas removal filter dust collector 4 are sequentially connected via a duct 12 in place of the incinerator filtration dust collector 21. The collected ash 15 collected by the dust collector 3 for dust removal is supplied to the ash melting furnace 8 through the duct, and the melting furnace treatment gas from the filtration dust collector 10 for the ash melting furnace is supplied. 13 is joined to the incinerator exhaust gas in the duct 12 in the upstream of the filter dust collector 4 for removing harmful gas through the duct, and the chemical supplied from the chemical supply pipe 7 is supplied to the combined exhaust gas in the duct 12. Further, the collected ash 16 collected by the harmful gas removing filtration dust collector 4 is supplied to the ash solidifying device 8.
According to such an exhaust gas treatment apparatus, the chemical can be input at one place, and the amount of the chemical can be easily adjusted. Therefore, the amount of the chemical is reduced and the ash melting furnace filter dust collector 10 captures the chemical. It is possible to reduce the collected ash 17 to be collected, to reduce the cement / chemical 19 required for the solidification treatment of the collected ash 17 and to reduce the final solidified product.
[0015]
FIG. 2 is a system diagram of an exhaust gas treatment apparatus showing another embodiment of the present invention.
2 is different from FIG. 1 in that the collected ash 16 from the harmful gas removal filtration dust collector 4 is joined to the melting furnace exhaust gas upstream of the ash melting furnace filtration dust collector 10 through a duct. This is the point.
By adopting such a configuration, in addition to the above effects, the unreacted chemical contained in the collected ash 16 can be reacted with the melting furnace exhaust gas, and it is possible to effectively use the charged chemical and reduce the amount of the charged chemical. Therefore, it is possible to further reduce the collected ash 17, the supply amount of the cement / chemical 19 for solidification treatment, and the final solidified product. Furthermore, since the melting furnace processing gas 13 from which the harmful gas has been removed is merged with the upstream flow of the filter dust collector 4 for the incinerator, corrosion due to harmful gas (corrosive gas) such as a duct for merging can be prevented. .
[0016]
In the above apparatus, when the behavior of harmful gas in the incinerator exhaust gas was investigated, about 10% of harmful gas was adsorbed on the collected ash 15 of the filter dust collector 3 for removing dust, and the remaining about 90%. It became clear that noxious gas is introduced into the noble gas removing filtration type dust collector 4 through the dust removing filtration dust collector 3. In addition, by using highly reactive slaked lime as a chemical that reacts with harmful gas, and by blowing about 1.5 times the amount of chemical from the chemical supply pipe 7 in an equivalent ratio with harmful gas, the filter dust collector 4 for removing harmful gas is used. As a result of measurement, it was found that the concentration of harmful gas in the outlet gas satisfies the required value. From these results, about 1/3 of the chemicals introduced from the chemical supply pipe 7 is contained in the collected ash 16 as unreacted components, and the collected ash 16 is filtered into a filtration dust collector for an ash melting furnace. The unreacted chemicals can be effectively used by blowing into 10 upstream melting furnace exhaust gas (including about 10% of the harmful gas described above). Even in tests using this device, the amount of harmful gas in the incinerator exhaust gas in the upstream of the filter dust collector 4 for removing harmful gas is reduced to about 90%, and in proportion to this, the chemical for removing harmful gas is introduced. The amount, the amount of cement and chemical used for solidifying collected ash, and the amount of the final solidified product could be reduced by about 10%.
[0017]
FIG. 3 is a system diagram of an exhaust gas treatment apparatus showing still another embodiment of the present invention.
FIG. 3 differs from FIG. 2 in that a part of the collected ash 16 from the harmful gas removal filtration dust collector 4, for example, an amount of gas necessary for removing harmful gas components in the surplus furnace exhaust gas, is collected. The ash collection 16 is merged with the melting furnace exhaust gas in the upstream of the filter dust collector 10 for the ash melting furnace, and the remaining collected ash 16 is supplied to the ash solidifying device 18.
By adopting such a configuration, in addition to the above effects, the amount of collected ash 16 can be adjusted according to the amount of harmful gas contained in the melting furnace exhaust gas. Processing efficiency can be improved.
[0018]
FIG. 4 is a system diagram of an exhaust gas treatment apparatus showing still another embodiment of the present invention.
4 is different from FIG. 2 in that the melting furnace processing gas 13 processed by the ash melting furnace filter dust collector 10 is merged with the processing gas downstream of the harmful gas removal filter dust collector 4. This is the point. By setting it as such a structure, the processing efficiency of the filtration dust collector 4 for harmful gas removal can be improved.
[0019]
【The invention's effect】
According to the first aspect of the present invention, the filtration dust collector for incinerator is installed in two stages, the treatment gas of the melting furnace exhaust gas is merged with the incinerator exhaust gas from which dust is removed, and harmful gas is added to the combined exhaust gas. By adding the removal chemical, it becomes easy to adjust the input amount of the chemical, reducing the amount of the chemical, reducing the collected ash, reducing the amount of cement / drug for solidifying the collected ash, and the amount of the final solidified product. Therefore, it is possible to extend the life of a landfill site.
According to the invention according to claim 2 or 3, in addition to the above-described effects, it is possible to effectively use unreacted chemicals for removing harmful gases, and further reduce harmful chemicals for removing harmful gases.
[Brief description of the drawings]
FIG. 1 is a system diagram of an exhaust gas treatment apparatus showing an embodiment of the present invention.
FIG. 2 is a system diagram of an exhaust gas treatment apparatus showing another embodiment of the present invention.
FIG. 3 is a system diagram of an exhaust gas treatment apparatus showing still another embodiment of the present invention.
FIG. 4 is a system diagram of an exhaust gas treatment apparatus showing still another embodiment of the present invention.
FIG. 5 is a system diagram of a prior art exhaust gas treatment apparatus.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Incinerator, 2 ... Gas cooling device, 3 ... Filter dust collector for dust removal, 4 ... Filter dust collector for harmful gas removal, 5 ... Induction fan, 6 ... Chimney, 7 ... Drug supply pipe, 8 Ash melting furnace, 9 ... gas cooling device, 10 ... filtration dust collector for ash melting furnace, 11 ... fan, 12 ... duct, 13 ... melting furnace exhaust gas, 14 ... incinerated ash, 15, 16, 17 ... collected ash , 18 ... Ash solidifying device, 19 ... Cement and chemicals, 20 ... Molten slag, 21 ... Filter dust collector for incinerator, 22 ... Collected ash.

Claims (2)

An incinerator filtration dust collector for removing dust in the exhaust gas of the incinerator, an ash melting furnace for melting the incineration ash of the incinerator and the collected ash collected by the incinerator filtration dust collector, In the exhaust gas treatment apparatus equipped with an ash melting furnace filtration dust collector for removing the dust in the exhaust gas of the ash melting furnace, as the filtration dust collector for the incinerator, a dust collection filtration dust collector and a harmful A filter dust collector for gas removal is installed in order, and means for supplying the collected ash collected by the dust dust filter dust collector to the ash melting furnace and the upstream filter dust collector for harmful gas removal only setting means for combining the melting furnace process gases from the ash melting furnace for filtration dust collector in incinerator exhaust gas, for removing harmful gas in the merging exhaust gas the harmful gas removal filtration precipitator upstream side Rutotomoni a means to inject drugs, all of the collected ash collected by the filtration dust collector for harmful gas removal Or the exhaust gas treatment apparatus, wherein a part of, is provided with means for mixing the melting furnace exhaust gas of the ash melting furnace for filtration precipitator upstream side.   An incinerator filtration dust collector for removing dust in the exhaust gas of the incinerator, an ash melting furnace for melting the incineration ash of the incinerator and the collected ash collected by the incinerator filtration dust collector, In an exhaust gas treatment apparatus comprising an ash melting furnace filtration dust collector for removing the dust in the exhaust gas of the ash melting furnace, the dust removal filtration dust collector and a harmful A filter dust collector for gas removal is installed in order, and means for supplying collected ash collected by the dust collector for filtering dust to the ash melting furnace and collected by the filter dust collector for removing harmful gas And a means for mixing the collected ash with the melting furnace exhaust gas upstream of the ash melting furnace filtration dust collector, and removing harmful gas from the incinerator exhaust gas upstream of the harmful gas removal filtration dust collector An exhaust gas treatment apparatus provided with means for feeding a chemical for the purpose.

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