JP2003240215A - Disposal processing plant - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a disposal processing plant reduced in operation cost thereof by reducing a cost to be required to eliminate dioxin from the exhaust gas. <P>SOLUTION: This disposal processing plant is provided with a thermal decomposition reactor 12, a combustion melting furnace 13, and an exhaust gas processing unit 6 for processing the exhaust gas with a bag filter 17. This plant is also provided with an activating means 30 for carbonizing a part of the residual carbon, not making it to direct to the combustion melting furnace 13 side, and for heating the carbon residual housed in a carbon residual housing case 111, and an activated carbon residual supply means 31 for supplying the activated carbon residual to the bag filter 17. The activating means 30 burns at least one of other one part of the carbon residual among the carbon residual selected from the heat decomposition residual and the exhaust gas exhausted from the carbon residual material housing case 111 to heat the carbon residual to be activated in the carbon residual housing case 111. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is provided with a pyrolysis reactor for pyrolyzing waste into a pyrolysis residue and a pyrolysis gas, and the pyrolysis gas and the carbon residue selected from the pyrolysis residue are provided. The present invention relates to a waste treatment plant provided with a combustion melting furnace for receiving and burning, and an exhaust gas treatment unit for treating exhaust gas with a bag filter.

[0002]

2. Description of the Related Art Conventionally, in the above waste treatment plant,
In order to remove dioxins from the exhaust gas, a bag filter is provided in the exhaust gas treatment section and an activated carbon supply section that supplies commercially available activated carbon to the bag filter is provided so that the activated carbon adsorbs dioxins.

[0003]

However, according to the above-mentioned conventional structure, since the activated carbon is supplied to the bag filter, there is a problem that the cost required for the activated carbon becomes high and the operating cost becomes high.

An object of the present invention is to provide a waste treatment plant capable of reducing the operating cost by reducing the cost required for removing dioxins from exhaust gas.

[0005]

The constitution, action and effect of the invention according to the constitution of claim 1 are as follows.

[Structure] In the waste treatment plant described at the beginning, a part of the carbon residue of the carbon residue is carbonized without being directed to the combustion melting furnace side and is housed in the carbon residue housing case. An activating means for heating and activating in a state, and an activated carbon residue supplying means for supplying an activated carbon residue to the bag filter are provided, and the activating means is one of carbon residues selected from the thermal decomposition residue. At least one of another part of the carbon residue and the exhaust gas discharged from the carbon residue containing case is burned to heat the carbon residue to be activated in the carbon residue containing case.

[Operation] The activation means heats a part of the carbon residue selected from the pyrolysis residue in the carbon residue accommodating case without directing it to the combustion melting furnace side. Activate. Then, the activated carbon residue supply means supplies the activated carbon residue to the bag filter of the exhaust gas treating section.

Like the activated carbon, the activated carbon residue is likely to adsorb dioxins. By supplying this carbon residue to the bag filter, dioxins in the exhaust gas can be removed.

[0009] For example, in the technique of supplying activated carbon to the bag filter to adsorb dioxins in the exhaust gas to the activated carbon, the cost required for activated carbon increases, but according to the configuration of claim 1, activated carbon is supplied to the bag filter. It doesn't have to be, and you don't have to pay for activated carbon.

Further, activated carbon and activated carbon residue may be supplied to a bag filter to remove dioxins in the exhaust gas. In such a case, a small amount of activated carbon is required and the cost required for activated carbon is reduced. Can be made cheaper.

When the activation target carbon residue in the carbon residue storage case is heated, another part of the carbon residue selected from the pyrolysis residue and the carbon residue storage case are discharged. At least one of the exhaust gas is burned and heated. This can eliminate the need for an electric heater or the like for heating the carbon residue in the carbon residue storage case.

[Effect] Therefore, the cost required for removing dioxins from the exhaust gas can be reduced and the operating cost can be reduced, and an electric heater for heating the carbon residue in the carbon residue accommodating case becomes unnecessary. As a result, it is possible to provide a waste treatment plant capable of saving energy as compared with the case of heating with an electric heater or the like.

Structure and operation of the invention according to the structure of claim 2
The effects are as follows.

[Structure] In the structure of the present invention according to claim 1, a neutralization processing section for neutralizing the exhaust gas discharged from the carbon residue accommodating case is provided, and the exhaust gas is neutralized before being burned. There is.

[Operation] In addition to the same operation as the operation according to the first aspect of the invention, the exhaust gas discharged from the carbon residue accommodating case is neutralized by the neutralization processing section and then burned. High temperature corrosion of the exhaust gas pipe can be prevented.

[Effects] Therefore, in addition to the same effects as the effects according to the first aspect of the invention, the waste treatment plant can be operated smoothly and the number of maintenances can be reduced. Could be provided.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a pyrolysis gasification and melting plant which is a treatment plant for general waste such as household waste and industrial waste such as car shredder dust and electric appliances.

The pyrolysis gasification and melting plant comprises a pretreatment facility 1, a pyrolysis facility 2, a pyrolysis residue sorting facility 3, a high temperature combustion melting facility 4, a boiler power generation facility 5, and an exhaust gas treatment facility 6. Next, each facility will be described.

[Pretreatment facility 1] The waste stored in the waste pit 7 is crushed by a crusher, and the crushed waste is sent to the thermal decomposition facility 2 by a transport device or the like.

[Pyrolysis equipment 2] Waste from the waste pit 7 is conveyed and supplied to the pyrolysis drum 12 (corresponding to a pyrolysis reactor), and the heating gas is supplied to the pyrolysis drum 12 by the heating gas supply means 102. To do. Then, while indirectly heating the waste with this heating gas, the waste is pyrolyzed into a pyrolysis gas of about 450 ° C. and a pyrolysis residue in an oxygen-free or low-oxygen atmosphere, and the pyrolysis gas is burned at a high temperature described later. It is sent to the melting furnace 13 and the pyrolysis residue is sent to the pyrolysis residue sorting facility 3.

[Pyrolysis Residue Sorting Equipment 3] Pyrolysis Drum 1
The pyrolysis residue from 2 is sent to the pyrolysis residue sorting device 99 by a vibration feeder 70 or the like.

In the thermal decomposition residue sorting device 99, the iron sorted by the magnetic separator 91 is recovered in the iron yard 96, and the aluminum sorted by the aluminum sorter is collected in the aluminum yard 97.
To collect.

Then, the pyrolysis residue after the iron, aluminum, etc. are selected is crushed by a crusher 93. The foreign matters of the crushed ones are collected in the foreign matter yard 98, the carbon residues other than the foreign matters are sent to the carbon residue silo 61 through the first carbon residue pipeline 32, and the carbon residue in the carbon residue silo 61 is removed by the carbon residue blower 48. It blows into the high temperature combustion melting furnace 13 of the high temperature combustion melting equipment 4 from the furnace top side through the second carbon residue pipeline 33.

[High Temperature Combustion and Melting Facility 4] Carbon residue, pyrolysis gas, and dust collecting dust are blown into the high temperature combustion and melting furnace 13 from the furnace top side, and these are swirled and burned. The incinerated ash and dust collected will be melted and continuously discharged from the bottom of the furnace.

[Boiler power generation equipment 5] Exhaust gas is cooled in the boiler radiation zone, and is brought to a uniform temperature in the evaporation tube group, and then sent to the heated steam group. The boiler 18 recovers heat from the steam, and the turbine 94 / generator 95 recovers it as electricity.

[Exhaust Gas Treatment Facility 6] A gas cooling tower 21 for the exhaust gas from the boiler 18, a first bag filter 17, and a second bag filter 22 are provided, and a chimney 25 for exhausting the exhaust gas processed by these devices is provided. is there.

Further, a dust silo 89 for accommodating the dust collecting dust from the boiler 18, the gas cooling tower 21, and the first bag filter 17 is provided, and the dust collecting dust in the dust silo 89 is passed through the dust blower 49 through the dust pipeline 50. As described above, the high temperature combustion melting furnace 13 is configured to be blown from the furnace top side.

A slaked lime supply mechanism 56 for supplying slaked lime to the second bag filter 22 is provided. The second bag filter 22 can remove HCl and SOx.

Further, a part of the carbon residue selected from the thermal decomposition residues in the thermal decomposition residue selection equipment 3 is stored in the activation furnace 35 without being directed to the high temperature combustion melting furnace 13 side. First, the activation means 30 for heating in the state and activating with carbon dioxide gas, and the activated carbon residue are
An activated carbon residue supply means 31 for supplying the bag filter 17 is provided.

Explaining the activation means 30, the first carbon residue pipe 32 and the third carbon residue pipe 34 of the thermal decomposition residue sorting facility 3 are branched, and the first conveyor 52 is connected to the third carbon residue pipe 34. And the first conveyor 52 is provided with the carbon residue storage case 11 in the activation furnace 35.
It is connected to 1. An agitator 36 is provided in the carbon residue receiving case 111, a gas tank 41 for storing carbon dioxide gas is connected to the carbon residue accommodating case 111, and exhaust gas from the carbon residue accommodating case 111 is supplied to the high temperature combustion melting furnace 13 to be guided to exhaust gas. A tube 40 is provided.

At the branch portion of the first carbon residue pipeline 32 and the third carbon residue pipeline 34, there are a first state in which carbon residue flows to the carbon residue silo 61 side and a second state in which carbon residue flows to the activation furnace 35 side. A switchable damper 51 that can be switched is provided, and carbon residue is supplied to the carbon residue storage case 111 by switching the damper 51 to the second state side. In this case, about 90% of the carbon residue selected from the pyrolysis residue is flowed to the carbon residue silo 61 side, and about 10% of the carbon residue is activated by the activation furnace 3
Flush to side 5.

The activation furnace 35 is configured as follows to heat the carbon residue stored in the carbon residue storage case 111. That is, from the first conveyor 52 to the fourth
The carbon residue pipeline 110 is branched and connected to a carbon residue combustion chamber 114 formed between the furnace wall 113 of the activation furnace 35 and the carbon residue accommodating case 111 so as to communicate with the fourth carbon residue conduit 110. An air supply fan 115 for blowing air into the carbon residue combustion chamber 114 is provided with a rotary valve 120 for feeding and supplying
Is provided, an auxiliary burner 116 that burns the carbon residue in the carbon residue combustion chamber 114 when the activation furnace 35 is started is provided, and an exhaust pipe 117 is connected to the carbon residue combustion chamber 114.

As described above, the activation furnace 35 includes the furnace wall 113.
A carbon residue accommodating case 111 is provided at an interval in the furnace body forming the carbon residue combusting chamber 114 between the furnace wall 113 and the carbon residue accommodating case 111;
The first conveyor 52 is connected to the carbon residue storage case 111 in the activation furnace 35, the fourth carbon residue pipeline 110 is connected to the carbon residue combustion chamber 114, the stirrer 36 is provided in the carbon residue receiving case 111, and a gas tank is provided. 41 is connected to the carbon residue storage case 111,
An exhaust pipe 40 is provided and configured.

The activated carbon residue supply means 31 includes a second conveyor 42 for conveying the activated carbon residue,
The activated carbon residue storage tank 43 that stores the carbon residue from the second conveyor 42, and the carbon residue in the tank 43 are passed through the activated carbon residue blower 45 through the activated carbon residue conduit 46 to the upstream side of the first bag filter 17. And an air transport mechanism 55 blown into the exhaust gas pipeline 44.

A fixed amount supply mechanism 53 is provided on the bottom side of the activated carbon residue storage tank 43 so that the activated carbon residue can be blown into the exhaust gas pipe 44 in a fixed amount.

With the above structure, the switching damper 51 is switched to the second state side to supply the carbon residue to the first conveyor 52, and the carbon residue from the first conveyor 52 is accommodated in the carbon residue accommodating case 111 of the activation furnace 35. The carbon residue from the first conveyor 52 is supplied to the carbon residue combustion chamber 114 via the fourth carbon residue conduit 110, and the carbon residue is supplied to the carbon residue containing case 111 in an amount substantially equal to that of the carbon residue. Supply the residue.

Then, carbon dioxide gas is uniformly supplied from the gas tank 41 into the carbon residue accommodating case 111 through the air diffusing tube, and the stirrer 36 is operated to stir the carbon dioxide gas and the carbon residue uniformly to ignite the auxiliary burner 116. , Carbon residue combustion chamber 114 with air supply fan 115
The carbon residue is burned while blowing air to heat the carbon residue to be activated in the carbon residue storage case 111. In this way, the temperature in the furnace is adjusted to 750-9
The temperature is raised at a predetermined temperature increase rate between 00 ° C.

After activating the carbon residue, the supply of the carbon residue to the carbon residue combustion chamber 114 is stopped and the combustion is stopped to cool the carbon residue. Then, the cooled carbon residue is supplied to the activated carbon residue storage tank 43, and the set amount of carbon residue is supplied to the air transport mechanism 55 side by the fixed amount supply mechanism 53 on the tank bottom side, and the set amount is set by the air transport mechanism 55. The carbon residue of the above is supplied to the exhaust gas pipeline 44 on the upstream side of the first bag filter 17.

The activated carbon residue easily adsorbs dioxins like activated carbon. By supplying this carbon residue to the first bag filter 17, dioxins in exhaust gas can be removed. . The carbon residue having adsorbed dioxins is sifted off from the filter cloth of the first bag filter 17 together with the dust, is accommodated in the dust silo 89, and is blown into the high temperature combustion melting furnace 13 from the furnace top side.

[Other Embodiments] As shown in FIG. 2, the activating means 30 discharges another part of the carbon residue selected from the pyrolysis residue and the carbon residue accommodating case 111. The exhaust gas may be burned to heat the carbon residue to be activated in the carbon residue storage case 111.

More specifically, the carbon residue storage case 111
The exhaust gas recovery pipe 118 is branched from the exhaust pipe 40 that guides the exhaust gas from the exhaust gas to the high-temperature combustion melting furnace 13, and the activation furnace 35
Is connected in communication with the carbon residue combustion chamber 114, and a baking soda packed tower 100 as a neutralization processing unit for neutralizing the recovered exhaust gas with sodium bicarbonate is connected to an intermediate part of the exhaust gas recovery pipe 118,
A gas suction fan 103 is provided in the branch pipe portion on the downstream side of the baking soda packed column 100.

With the above structure, the exhaust gas from the carbon residue storage case 111 is collected in the exhaust gas recovery pipe 118 by driving the gas suction fan 103, neutralized through the baking soda packed column 100, and the carbon residue combustion chamber 114 of the activation furnace 35. It is supplied back to and burned.

In place of this structure, only the exhaust gas discharged from the carbon residue storage case 111 is burned in the carbon residue combustion chamber 114, and the carbon residue storage case 111.
The carbon residue to be activated may be heated.

The present invention can be applied to a waste treatment plant provided with a fluidized bed type pyrolysis furnace for pyrolyzing waste, instead of the pyrolysis drum 12. The fluidized bed type pyrolysis furnace is generally called a pyrolysis reactor.

The present invention can also be applied to the case where steam is used as the activation gas. The collected exhaust gas may be neutralized with a substance other than baking soda. The numerical values mentioned in the above embodiment are examples and may be different numerical values.

[Brief description of drawings]

FIG. 1 Schematic of waste treatment plant

FIG. 2 is a schematic diagram of a waste treatment plant according to another embodiment.

[Explanation of symbols] 6 Exhaust gas treatment section 12 Pyrolysis reactor 13 Combustion melting furnace 17 Bug Filter 30 activation means 31 Activated carbon residue supply means 100 Neutralization processing section 111 Carbon residue storage case

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) C07B 35/06 F23G 5/00 115Z 4D004 37/06 5/16 B 4H006 F23G 5/00 115 5/44 Z 5/16 B09B 3/00 303Z 5/44 B01D 53/34 134E F23J 15/00 F23J 15/00 Z F-term (reference) 3K061 AA24 AB02 AB03 AC01 BA05 CA07 DA02 DA12 DA18 DA19 FA02 FA09 FA17 FA21 FA28 3K065 AA24 AB02 AB03 AC01 AC19 BA05 HA03 3K070 DA32.

Claims (2)

[Claims] 1. A combustion melting system in which a thermal decomposition reactor for thermally decomposing waste into thermal decomposition residue and thermal decomposition gas is provided, and the thermal decomposition gas and carbon residue selected from the thermal decomposition residue are received and burned. A waste treatment plant in which a furnace is provided and an exhaust gas treatment unit for treating exhaust gas with a bag filter is provided, wherein a part of the carbon residue of the carbon residue is carbonized without being directed to the combustion melting furnace side. Along with
An activating means for heating and activating in a state of being accommodated in the carbon residue accommodating case, and an activating carbon residue supplying means for supplying the activated carbon residue to the bag filter are provided,
The activation means burns at least one of the carbon residue of another part of the carbon residue selected from the thermal decomposition residue and the exhaust gas discharged from the carbon residue housing case to burn the carbon residue housing case. A waste treatment plant configured to heat the carbon residue to be activated within. 2. The waste according to claim 1, further comprising a neutralization processing unit for neutralizing the exhaust gas discharged from the carbon residue containing case so as to neutralize and burn the exhaust gas. Processing plant.