JP2002035538A - Method and equipment for cleaning waste gas - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for cleaning a waste gas by which harmful substances such as matter that remains not combusted can be effectively removed from a waste gas such as a combustion exhaust gas by means of simple equipment and to provide equipment for cleaning. SOLUTION: There are provided a method for cleaning a waste gas comprising passing a waste gas through a layer, desirably a fixed, moving, or a fluidized one, of a carbonized carbide of a refuse solid fuel and equipment for cleaning a waste gas having a moving layer type adsorptive collector 20 packed with a carbonized carbide of a refuse solid fuel; a waste gas feed pipe 8 and a cleaned gas discharge pipe 9 connected to the bottom and the top of the collector 20; a feeder 11 and a discharger 13 for the carbonized carbide provided at the top and the bottom of the collector 20; a device 21 for measuring the gas pressure loss across the collector 20; a level meter 23 for the carbonized carbide; a control unit 22A that controls the discharge rate of the discharger 13 according to the measurements sent from the device 21; and a controller 22B that controls the rate of feed from the feeder 11 according to the measurements sent from the meter 23.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a device for purifying exhaust gas generated in various processes such as flue gas, and more particularly to a method for effectively removing harmful substances in flue gas such as unburned components in flue gas. In addition, the present invention relates to an exhaust gas cleaning method and a cleaning facility capable of effectively utilizing industrial waste.

[0002]

2. Description of the Related Art Various combustion furnaces such as waste (garbage) incinerators, boilers, iron scrap melting furnaces, kilns, metal melting and smelting furnaces, and firing furnaces provide unburned substances, submicron-order particulate matter, An exhaust gas containing a chlorinated hydrocarbon compound is generated. For this reason, from the viewpoint of environmental protection, methods for preventing generation of harmful substances contained in these exhaust gases and methods for removing harmful substances have been studied and put to practical use.

However, for example, in case of suppressing the generation of unburned requires hot combustion with improved air ratio of the combustion air, secondary pollution is generated, such as NO _x, these removal device Installation is required. In addition, in an iron scrap melting furnace, complicated equipment such as an exhaust gas quenching device and a dust collector is required to prevent the generation of chlorine-based hydrocarbon compounds and to collect metal fine particles.

[0004] For this reason, there is a demand for the development of a method and a facility for purifying exhaust gas which can effectively remove the above-mentioned harmful substances with a simple facility.

[0005]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art and effectively removes harmful substances in exhaust gas such as unburned components in combustion exhaust gas with simple equipment. It is an object of the present invention to provide an exhaust gas purifying method and a purifying equipment capable of performing the method.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, have arrived at the present invention in which carbonized carbonization of refuse solid fuel is used as an agent for adsorbing and collecting harmful substances. . That is, the first invention is a method for purifying exhaust gas, which comprises causing exhaust gas to flow through a dry-distilled carbide layer of refuse solid fuel.

In the first aspect of the present invention, it is preferable that the dry-distilled carbide layer of the solid waste fuel is a fixed bed, a moving bed or a fluidized bed (a preferred embodiment of the first invention). The second invention includes a moving bed type adsorption / collector 20 filled with dry distillation carbide of refuse solid fuel, an exhaust gas supply pipe 8 connected to a lower part of the adsorption / collector 20, A clean gas discharge pipe 9 connected to an upper portion of the collector 20; a supply device 11 for dry-distilled carbide of refuse solid fuel disposed at an upper portion of the adsorber / collector 20; A discharge device 13 for dry-distilled carbides of refuse solid fuel disposed at the bottom,
A gas pressure loss measuring device 21 on the gas inlet side and gas outlet side of the collector 20, a level meter 23 of dry-distilled carbide of refuse solid fuel in the adsorption / collector 20, and a gas pressure loss measuring device
A control device 22A for controlling the discharge speed of the discharge device 13 based on the measurement result of 21 and a control device 22B for controlling the supply speed of the supply device 11 based on the measurement result of the level meter 23. This is an exhaust gas purification facility.

In the first invention, the preferred embodiment of the first invention and the second invention, the dry-distilled carbide of the solid refuse fuel is a dry-distilled carbide produced by dry-distilling a molded product of waste. Is not particularly limited,
Combustible materials selected from refuse, crushed, dried, dry-carbonized carbonized fuel produced by refrigerated solid fuel obtained by molding, or combustible materials selected from refuse, crushed,
It is more preferable to use a dry-distilled carbide produced by dry-distilling and carbonizing the refuse solid fuel obtained by molding and drying, or a mixture of the dry-distilled carbides produced in the above.

Further, the moving bed in the preferred embodiment of the first invention and the moving invention in the second invention is not limited to a continuous moving bed in which the dry-distilled carbide continuously moves with time. It may be an intermittent moving bed in which the carbonized carbide moves intermittently with time.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. The present inventors have conducted intensive studies in order to solve the above-mentioned problems of the prior art, and as a result, have obtained the following findings (1) to (3), and have reached the present invention. (1) Utilization of refuse solid fuel as carbon adsorbent, fuel, and reducing agent: Refuse carbon from refuse solid fuel has a large specific surface area and porosity, and has the ability to adsorb unburned components in combustion exhaust gas. Industrial waste is used as both a cleansing agent for exhaust gas and various fuels and a reducing agent by using the carbonized carbonized material of the refuse solid fuel as an adsorbent and using the carbonized carbonized material after use as a fuel and a reducing agent. It can be used effectively.

(2) A method for purifying exhaust gas using a packed bed of dry-distilled carbide of refuse solid fuel: The use of a fixed bed, a moving bed and a fluidized bed filled with dry-distilled carbide of refuse solid fuel has the following advantages. The effect is obtained. (2-1) Purification method of exhaust gas using fixed bed filled with dry-distilled carbide of refuse solid fuel: By using fixed bed filled with dry-distilled carbide of refuse solid fuel, dry-distilled carbide layer of refuse solid fuel is adsorbed By exhibiting the functions of both the agent and the filter, harmful substances in the exhaust gas such as unburned components in the combustion exhaust gas can be effectively removed with simple equipment.

(2-2) Method and apparatus for purifying exhaust gas using a moving bed filled with dry-distilled carbide of refuse solid fuel: By using a moving bed filled with dry-distilled carbide of refuse solid fuel, solid waste can be solidified. The dry carbonized carbon layer of the fuel functions as both an adsorbent and a filter, not only effectively removing harmful substances in the exhaust gas such as unburned components in the combustion exhaust gas, but also supplying new dry carbonized carbon sequentially. Therefore, harmful substances in the exhaust gas can be more effectively removed.

Further, in the case of the moving bed system, the above-mentioned excellent effects can be obtained, and the equipment can be continuously operated with simple and small equipment without complicating the equipment. (2-3) Purification method of exhaust gas using fluidized bed filled with dry-distilled carbide of refuse solid fuel: By using fluidized bed filled with dry-distilled carbide of refuse solid fuel, dry-distilled carbide layer of refuse solid fuel is adsorbed Not only can it function effectively to remove harmful substances in exhaust gas such as unburned components in combustion exhaust gas, but also, as will be described later, it is possible to selectively remove carbonized charcoal that has reduced its performance by adsorbing harmful substances. The carbonized waste of the solid fuel is efficiently used as an adsorbent, and continuous operation is possible.

Hereinafter, the present invention relates to I. Dry carbonization of refuse solid fuel, II. A method of purifying exhaust gas using a fixed bed filled with dry carburetion of refuse solid fuel, and III. Of exhaust gas using a moving bed and its purification equipment, and IV. Purification method of exhaust gas using a fluidized bed filled with dry-distilled carbide of refuse solid fuel.

I. Carbonized carbonized refuse solid fuel: In recent years, refuse disposal has attracted public interest. In other words, due to the location problem when constructing a waste incineration facility, only combustible waste is sorted, crushed, dried, molded, and solid waste recycling technology for environmentally friendly waste is actively used as fuel. Development is underway.

Refuse-derived fuel (RDF)
Or WDF: Waste Derived Fuel) is a solid fuel produced by crushing, drying, and molding combustible materials selected from municipal waste, household waste, industrial waste, general waste, etc., or the above combustible materials. It is a solid fuel produced by crushing, forming and drying. The refuse solid fuel obtained above is burned in conventional stoker incinerators or fluidized bed incinerators, heat is recovered by a waste heat boiler, and a refuse treatment system that uses the obtained hot water for hot water supply and cooling / heating is being realized. is there.

However, the refuse solid fuel described above has poor flammability, and must be burned in the above-mentioned special incinerator, and there is a problem that its use is limited. On the other hand, when carbonized waste (refuse solid fuel) is formed, carbonized carbon dioxide and carbonized gas are generated. The calorific value (lower calorific value) of the solid waste fuel is about 14700kJ / kg, and it has excellent combustibility and can be used as various fuels. Can be effectively used as a heat source for carbonization.

In the present invention, the carbonized carbonized waste (hereinafter, also referred to as RDF carbonized carbide) of the refuse solid fuel is:
It is used as a purifying agent for exhaust gas by making use of its property of having a large specific surface area and a high porosity and having a performance of adsorbing harmful substances in exhaust gas such as unburned components in combustion exhaust gas. The dry-distilled carbide of the refuse solid fuel in the present invention (: RDF dry-distilled carbide) is not particularly limited as long as it is a dry-distilled carbide produced by dry-distilling and carbonizing a molded article of garbage. It is preferably used.

Combustible materials selected from general waste such as municipal waste, household waste, industrial waste, general waste, and shredder dust obtained by crushing home electric appliances, automobile parts, and the like, or garbage that is a mixture thereof. Crush things,
A dry-distilled carbide produced by dry-distilling and carbonizing the refuse solid fuel obtained by drying and molding (: dry-distilled carbon of refuse solid fuel). A dry-distilled carbide produced by crushing, shaping, and drying the combustible material described above to obtain a refuse solid fuel, which is obtained by dry-distillation and carbonization (: dry-distilled carbide of refuse solid fuel).

A mixture of the carbonized carbonized materials produced in the above ((Carbonized carbonized solid waste fuel)). The carbonization temperature of the refuse solid fuel is preferably 300 to 1200 ° C.
More preferably, the temperature is from 400 to 900 ° C. If the carbonization temperature of the refuse solid fuel is less than 300 ℃ and more than 1200 ℃,
In any case, the adsorption capacity of the dry-distilled carbide of the refuse solid fuel decreases.

II. Method for Purifying Exhaust Gas Using Fixed Bed Filled with Dry Distilled Carbide (: RDF Dry Distilled Carbide) of Garbage Solid Fuel: FIG. 1 shows a fixed bed suitably used in the exhaust gas cleaning method of the present invention. An example of a system for purifying exhaust gas (hereinafter also referred to as an exhaust gas cleaning device) is shown in a longitudinal sectional view.

In FIG. 1, reference numerals 1A and 1B denote adsorption / collectors of a fixed-bed type, and 2 denotes a dry-distilled carbide (: R) of refuse solid fuel.
DF carbonized carbonized), 3 is exhaust gas, 4 is clean gas, 5A and 5B are
A hopper for supplying RDF carbonized carbide, 6A, 6B and 6C are belt conveyors, 7 is a hopper for storing RDF carbonized carbide after use, 8 is an exhaust gas supply pipe, 9 is a clean gas discharge pipe, 10 is a blower, 11 Is a rotary valve (rotary feeder)
RDF carbonized carbide feeder, 12A and 12B are valves, 1
3,14 Emission device, f ₁ of RDF carbonization carbide which is a rotary valve (rotary feeder) indicates the direction of movement of the RDF carbonization carbide.

In FIG. 1, the belt conveyor 6B
Is a belt conveyor that can move in the direction perpendicular to the paper surface of FIG. 1, and FIG. 1 illustrates a state where the belt conveyor is retracted to the opposite side to the paper surface in the direction perpendicular to the paper surface. In other words, the exhaust gas cleaning equipment shown in Fig. 1 is a fixed-bed processing equipment with a two-tower switching system in which the adsorption / collector 1A and 1B are filled with RDF dry-distilled carbide, and the exhaust gas is purified by the following procedure. You.

The exhaust gas 3 is adsorbed and discharged from an exhaust gas supply pipe 8.
Hazardous substances such as unburned substances in the exhaust gas are adsorbed and collected in the process of being supplied to the collector 1B and passing through the packed bed (fixed bed) of the RDF dry-carbonized carbide 2 in the adsorber / collector 1B, and purified. The gas 4 is discharged out of the system via the clean gas discharge pipe 9 and the blower 10. On the other hand, in the adsorber / collector 1A where the adsorber / collector has been completed, the used RDF dry-distilled carbide is extracted and then adsorbed via the belt conveyor 6A, the hopper 5A, and the rotary valve 11, as shown in FIG. -Fill the collector 1A with new RDF carbonized char.

When the adsorption / collector 1B is filled with new RDF dry carbonized carbide, the belt conveyor 6B is moved to the same position as the belt conveyor 6A in the direction perpendicular to the plane of FIG. Conveyor 6B, hopper 5B,
New RD for adsorption / collector 1B via rotary valve 11
F Fill with carbonized char. According to the fixed bed type exhaust gas cleaning equipment illustrated in FIG. 1 described above, the dry-distilled carbide layer of the refuse solid fuel functions as both an adsorbent and a filter, and the gaseous unburned matter in the exhaust gas, The particulate unburned matter, metal fine particles and metal oxide fine particles are adsorbed and collected,
Exhaust gas can be purified.

Further, according to the fixed bed type exhaust gas cleaning equipment illustrated in FIG. 1, gaseous unburned components, particulate unburned components, metal fine particles and metal oxide fine particles in the exhaust gas are treated in the same processing equipment. Since it is possible to adsorb and collect the exhaust gas, the exhaust gas can be purified by a simple exhaust gas treatment facility. III. Exhaust gas purification method and equipment using a moving bed filled with dry-distilled carbide (: RDF dry-distilled carbide) of refuse solid fuel: Fig. 2 shows a transfer method preferably used in the exhaust gas purification method of the present invention. An example of a bed-type exhaust gas cleaning facility (: exhaust gas cleaning facility) is shown in a longitudinal sectional view.

In FIG. 2, 5 is a hopper for supplying RDF dry-distilled carbide, 12 is a valve, 20 is an adsorber / collector of a moving bed type, 21 is a gas inlet side and a gas outlet of the adsorber / collector 20. Side gas pressure loss measuring device (hereinafter referred to as gas pressure loss measuring device), 22A is a control device for controlling the discharge amount of discharge device 13 which is a rotary valve rotation speed control device (hereinafter referred to as discharge amount control device). , 22B is a control device for controlling the supply amount of the supply device 11, which is a rotary valve rotation speed control device (hereinafter referred to as a supply amount control device), 23 is an RDF dry distillation carbide level meter, and 24A is an adsorption / collection device 20. An exhaust gas analyzer at the inlet, 24B is a clean gas analyzer at the outlet of the adsorption / collector 20, 25 is an exhaust gas purification rate calculator, 26 ₁ , 26 ₂ , 26 ₃ ,
26 ₄ measurement, analysis, calculation results of the signal, 26 ₅ denotes a control signal, other reference numerals indicate the same contents as FIG.

Further, the level meter 23 of RDF carbonized carbonized
This is a level meter on the upper surface of the DF carbonized carbide packed layer, and a laser distance meter, an ultrasonic distance meter, or the like can be used.
That is, in the exhaust gas cleaning equipment shown in FIG. 2, the adsorption / collector 20 is a moving bed type treatment equipment, and the moving bed type adsorption / collector 20 filled with dry distillation carbide of refuse solid fuel and the adsorption / collector 20 An exhaust gas supply pipe 8 connected to the lower part of the collector 20,
Clean gas discharge pipe 9 connected to the upper part of adsorption / collector 20
And a supply device 11 for dry-distilled carbide of refuse solid fuel disposed at the upper part of the adsorber / collector 20 and a discharge device 13 for dry-distilled carbide of refuse solid fuel disposed at the lower part of the adsorber / collector 20 A gas pressure loss measuring device 21 on the gas inlet side and the gas outlet side of the adsorbing / collecting device 20, a level meter 23 for dry distillation char of solid fuel in the adsorbing / collecting device 20, and a gas pressure loss measuring device A control device 22A that controls the discharge speed of the discharge device 13 based on the measurement result of the
This is an exhaust gas cleaning facility having a control device 22B for controlling the supply speed of the exhaust gas.

In the exhaust gas cleaning equipment shown in FIG.
Exhaust gas is purified by the following procedure. That is, the exhaust gas 3 is supplied from the exhaust gas supply pipe 8 to the adsorber / collector 20, and passes through the moving bed of the RDF dry carbonized carbide 2 in the adsorber / collector 20, and emits harmful substances such as unburned components in the exhaust gas. But adsorption
The clean gas 4 is collected and the clean gas exhaust pipe 9 and the exhaust fan 10
It is discharged out of the system via.

On the other hand, the RDF dry-distilled carbide 2 that has adsorbed and trapped harmful substances such as unburned components in the exhaust gas descends in the adsorber / collector 20 and discharges the exhaust device (rotary valve) 13 and the belt conveyor 6C. And is stored in the storage hopper 7, and new RDF carbonized charcoal is transferred to the belt conveyor.
6A, the hopper 5, and the supply device (rotary valve) 11 are sequentially charged into the suction / collector 20.

In the exhaust gas cleaning equipment shown in FIG. 2, the moving (falling) speed of the RDF dry distillation carbide 2 in the adsorber / collector 20 is controlled by the following method. That is,
Exhaust gas analyzer 24A on the inlet side of adsorption / collector 20
A component corresponding to the type of exhaust gas is analyzed by the clean gas analyzer 24B at the outlet side of the collector 20, and a signal 2 of the analysis result is obtained.
6 _2, 26 ₃ is transmitted to the exhaust gas purification ratio calculating unit 25.

Next, the exhaust emission reduction rate calculation unit 25, the signal 26 ₄ of the exhaust gas purification ratio is transmitted to the control device (rotary valve speed control system) 22A, and lower than the exhaust gas purification rate exhaust gas purification rate is predetermined case, the control device control signal 26 ₅ (rotary valve speed control system) 22A is transmitted to the discharge device 13, such as by an increase in the rotational speed of the rotary valve motor, to increase the discharge rate.

By the above-described control, the RDF dry-distilled carbide in the lower portion of the adsorber / collector 20 that adsorbs and collects unburned components in the exhaust gas is sequentially discharged. On the other hand, a signal from the level meter 23 is transmitted to a control device (rotary valve rotation speed control device) 22B.
And the level of the upper surface of the packed bed of the RDF carbonized carbide in the adsorber 20 is maintained at a constant level by the supply of the carbonized carbonized RDF 2 from the hopper 5.

In the exhaust gas cleaning equipment shown in FIG. 2, the RDF in the adsorber / collector 20 is combined with the control described above.
Filtration of particulate unburned components in the exhaust gas by the carbonized carbonized bed, and the increase in gas pressure loss in the adsorption / collector 20 due to the adhesion of unburned gaseous components in the exhaust gas to the RDF carbonized carbide as follows: Perform control. That is, a gas pressure loss measuring device
Signal 26 ₁ from 21, is transmitted to the control device 22A, the adsorbent-
The discharge speed of the discharge device 13 (the number of rotations of the rotary valve) is controlled so that the pressure loss of the gas in the collector 20 becomes equal to or less than a certain value over time.

In the above control method, in addition to the above control, a signal of the result of the analysis of the clean gas at the outlet side by the clean gas analyzer 24B at the outlet side of the adsorption / collector 20 is used.
26 ₃ directly, also transmitted to the control unit 22A, in conjunction with the exhaust gas purification rate can also be controlled absolute value of the analytical values of the outlet side of the clean gas. In the exhaust gas cleaning equipment shown in FIG. 2, when processing exhaust gas containing components that cannot be applied to continuous instrument analysis such as dioxins, the pressure loss of the gas in the adsorption / collector 20 and the exhaust gas purification A calibration curve, which is a relational equation with the rate, is created.Based on the obtained calibration curve, the control based on the gas pressure loss described above is performed, and the level control of the upper surface of the RDF carbonized carbonized packed bed using the level meter 23 described above is performed. I do.

In this case, it is preferable that control is performed by sequentially updating the above-mentioned calibration curve. According to the control method described above, the adsorption / collector 20 is controlled by the level meter 23.
The amount of the RDF carbonized carbonized in the RDF can be maintained at a predetermined amount, and the adsorption capability of the RDF carbonized carbonized in the adsorber / collector 20 can be ensured. According to the moving bed type exhaust gas cleaning equipment illustrated in FIG. 2 described above, the dry-distilled carbide layer of the refuse solid fuel functions as both an adsorbent and a filter, and the gaseous unburned matter and fine particles in the exhaust gas Not only can effectively remove particulate unburned matter, metal fine particles and metal oxide fine particles, but also because new dry-distilled carbides are successively supplied, harmful substances in exhaust gas can be more effectively adsorbed and removed. , And continuous operation becomes possible.

Further, according to the moving bed type exhaust gas cleaning equipment illustrated in FIG. 2, the gaseous unburned portion, the particulate unburned portion, the metal fine particles and the metal oxide fine particles in the exhaust gas are treated in the same processing equipment. , The exhaust gas can be purified with a simple exhaust gas treatment facility, and the exhaust gas treatment facility can be downsized because only one adsorption / collection device is required.

In the exhaust gas cleaning equipment shown in FIG. 2, depending on the control method employed, the moving form of the moving bed is a continuous moving bed in which RDF carbonized carbide continuously moves with time, and a carbonized carbonized bed. The intermittent moving layer which moves intermittently with time becomes a moving layer or a combination of the two. IV. Purification method of exhaust gas using fluidized bed filled with carbonized carbonized waste fuel (RDF carbonized carbonized: RDF):
An example of a fluidized bed type exhaust gas cleaning apparatus suitably used in the exhaust gas cleaning method of the present invention is shown by a longitudinal sectional view.

In FIG. 3, reference numeral 30 denotes a fluidized bed type adsorber / collector, 31 denotes a dispersion plate (a perforated plate), and 32 denotes a fine RDF.
Carbonized carbonized, 33 is cyclone, 34 is RDF carbonized carbonized circulation pipe, 35 is valve of RDF carbonized carbonized supply pipe 37, 36 is opening control device of valve 35, 37 is RDF carbonized carbonized supply pipe, 38 ₁ , 38
_2, 38 _3, 38 ₄ measurement, analysis, calculation results of the signal, 38 ₅ denotes a control signal, other reference numerals indicate the same contents as FIG. 1, FIG.

That is, in the exhaust gas purifying equipment shown in FIG. 3, the adsorbing / collecting unit 30 is a fluidized bed processing apparatus, and the exhaust gas is purified in the following procedure. The exhaust gas 3 is supplied from the exhaust gas supply pipe 8 to the adsorber / collector 30, and in the process of passing through the fluidized bed of the RDF carbonized carbonized carbon dioxide 2 of the adsorber / collector 30, harmful substances such as unburned components in the exhaust gas are removed. Adsorbed and collected by RDF carbonized carbonized and purified.

The clean gas is discharged to the outside of the system via the clean gas discharge pipe 9 and the exhaust fan 10 after the fine RDF dry carbonized carbon partially entrained in the gas is removed and recovered by the cyclone 33. On the other hand, particles of RDF carbonized carbonized carbon, which have increased in density by adsorbing and collecting unburned substances such as unburned matter in the exhaust gas, are dispersed into a dispersion plate (: perforated plate) 31 and a discharge device (rotary valve) 13
Is discharged from the adsorber / collector 30 through the belt conveyor
It is stored in the storage hopper 7 via 6C.

Further, a new fine RDF carbonized carbonized substance 32 is
The air is supplied to the adsorber / collector 30 from the RDF dry distillation carbide supply pipe 37 by pneumatic transportation. In the exhaust gas cleaning equipment shown in FIG. 3, a new R
The DF carbonized carbide is supplied into the adsorber / collector 30. That is, a component according to the type of exhaust gas is analyzed by the exhaust gas analyzer 24A on the inlet side of the adsorption / collector 30 and the clean gas analyzer 24B on the outlet side of the adsorption / collector 30, and a signal 38 of the analysis result is obtained. _2, 38 ₃ is transmitted to the exhaust gas purification ratio calculating unit 25.

Next, the exhaust emission reduction rate calculation unit 25, the signal 38 ₄ of the exhaust gas purification ratio is transmitted to the opening control unit 36 of the valve 35, if it falls below the exhaust gas purification rate exhaust gas purification rate is predetermined, control signal 38 ₅ from the opening control unit 36 of the valve 35 is transmitted to the valve 35 increases the opening degree of the valve 35. On the other hand, the RDF dry-distilled carbide that has settled to the bottom in the adsorber / collector 30 due to the increase in density by adsorbing and collecting unburned components in the exhaust gas is sequentially discharged by the discharge device (rotary valve) 13.

In the exhaust gas cleaning equipment shown in FIG. 3, the RDF inside the adsorber / collector 30 is combined with the above control.
The following control is performed to keep the filling amount of the carbonized carbide constant. That is, when the filling amount of the RDF dry-distilled carbide in the adsorber / collector 30 is smaller than a predetermined amount and the pressure loss of the gas in the adsorber / collector 30 is reduced, the signal 38 from the gas pressure loss measuring device 21 ₁ is transmitted to the opening control device 36 of the valve 35, and the opening of the valve 35 is controlled so that the pressure loss of the gas in the adsorption / collection device 30 becomes equal to or more than a certain value with time.

By the above-described control, the filling amount of the RDF dry-distilled carbide in the adsorption / collection unit 30 is maintained at a predetermined amount. This is because, in the case of a fluidized bed, there is no increase in pressure loss of the gas in the packed bed due to the capture of fine particles in the exhaust gas.
This is because by measuring the change in the pressure loss of the gas in the collector 30, it is possible to detect the change in the filling amount of the RDF dry-distilled carbide in the adsorption / collector 30.

In the control method described above, in addition to the control described above, the signal of the result of the analysis of the clean gas on the outlet side by the clean gas analyzer 24B on the outlet side of the adsorption / collector 30 is used.
38 ₃ directly, also transmitted to the opening control unit 36 of the valve 35, in conjunction with the exhaust gas purification rate can also be controlled absolute value of the analytical values of the outlet side of the clean gas. According to the fluidized-bed type exhaust gas cleaning equipment illustrated in FIG. 3 described above, the dry-distilled carbide layer of the refuse solid fuel functions as an adsorbent, and effectively removes harmful substances such as unburned components in the exhaust gas. Can be removed.

Further, according to the fluidized-bed type exhaust gas purifying equipment shown in FIG. 3, the particles of the carbonized carbonized matter, which adsorb harmful substances and deteriorate in performance, are selectively adsorbed and collected by the increase in their density. It moves to the bottom inside the vessel 30 and
Since it is discharged from the collector 30, the RDF carbonized carbonized carbon can be used very efficiently as an adsorbent, and continuous operation is possible.

Although the present invention has been described above, the adsorbent / collecting agent used in the present invention is a dry-distilled carbide of refuse solid fuel, such as activated carbon, which does not involve any special treatment such as steam activation, and is therefore easy to manufacture. Therefore, the present invention can be easily applied as an industrial exhaust gas cleaning method and cleaning equipment. In addition, the carbonized carbonized waste solid fuel used in the present invention can be effectively used as various fuels, reducing agents for various metal oxide-containing substances such as iron ore, etc., and according to the present invention, industrial waste can be used for environmental protection. It can be effectively used for both energy saving and resource saving.

It is to be noted that the dry-distilled carbide after use has its adsorption and
The use of either a fuel or a reducing agent depending on the components of the trapping substance makes the adsorption / trapping substance harmless.

[0050]

EXAMPLES The present invention will be described below more specifically based on examples. (Example 1) Using a simulated flue gas, an experiment of adsorption and collection of various unburned carbides and graphitized substances in the flue gas was conducted.

FIG. 4 is a longitudinal sectional view of the adsorption / collection experiment apparatus used in this embodiment. In FIG. 4,
40 is a sample, 41 is a cage made of wire mesh for holding the sample, 42 is an incense stick which is a simulated fuel, 43 is an electric heater, 44 is a support, 44a is a pillar of the support, 45 is a fishing line, 46a and 46b are High sensitivity balance, 47 is a rubber seal member, 48 is an acrylic adsorption / collection chamber,
49 a combustion chamber, 50 is the suction pump, 51 is an air supply pipe for combustion, 52 combustion exhaust gas feed pipe, 53 anti-vibration table, the 54 casing, f ₂ is the flue gas flow direction, f ₃ is for combustion Indicates the direction of air flow.

That is, in the present embodiment, the incense stick (: simulated fuel) was burned using the adsorption / collection experiment apparatus shown in FIG. An experiment of adsorbing and collecting with sample 40 was performed. Basket 41
Is a highly sensitive balance with a fishing line 45 (repeatability: 0.1mg
), The weight increase of the sample 40 that adsorbed and collected unburned components and the like was continuously measured, and the adsorption and collection performance of the sample 40 was evaluated from the obtained measurement results.

In this experiment, the high-sensitivity balance 46b was used.
The combustion speed of the incense stick (: simulated fuel) was also measured. The experimental conditions were as follows. (Experimental conditions :) Sample filling amount: 5 g Sample type: Six types of samples A to F shown below.

Sample A: Carbonized carbonized solid waste fuel (: R
DF dry-distilled carbide) Dry-distilled carbide produced by crushing, drying, and shaping combustible materials selected from municipal solid waste at 700 ° C. Sample B: pitch coke Sample C: blast furnace coke Sample D: coke for electric furnace Sample E: charcoal Sample F: graphite Burning rate of incense stick (: simulated fuel): 2.7 g / h Supply amount of combustion air: 60 l / h Adsorption / collection time: 7 hours The above experiment In addition, the specific surface area and the porosity of each sample before the experiment were measured by the BET method (nitrogen adsorption) and the mercury porosimeter, respectively.

FIGS. 5 and 6 show the obtained experimental results in comparison with the specific surface area and porosity of each sample. 5 and 6
As shown in the figure, there was no correlation between the porosity of the sample and the amount of adsorption and collection, but there was a correlation between the specific surface area of the sample and the amount of adsorption and collection. .

From these results, the following findings (1) and (2) were obtained regarding the adsorption and collection of unburned components in the combustion exhaust gas. (1) Carbonized carbonized waste solid fuel (RDF carbonized carbonized)
Has much better adsorption and collection performance for other carbides and graphitized materials. (2) Carbonized char of solid fuel with large specific surface area (: R
DF dry-distilled carbide) had excellent adsorption and collection performance, and a correlation was found between the specific surface area of various carbides and graphitized materials and the amount of adsorption and collection.

From the above results, including RDF carbonized carbonized,
It is considered that the adsorption and collection of unburned components in the combustion exhaust gas by these carbides and graphitized materials is mainly due to the adsorption of unburned components on the surfaces of the carbides and graphitized products. However, since other carbides and graphitized materials with a small specific surface area also have adsorption / collection performance, these carbides and graphitized materials, including RDF carbonized charcoal, can absorb and combust unburned components in the combustion exhaust gas.
It is considered that the collection depends not only on the adsorption but also on the adhesion of unburned matter to the surface of the carbide and the graphitized material and / or the filtration of the particulate unburned matter by these packed beds.

(Example 2) Using the combustion exhaust gas from a refuse incinerator, dry-distilled carbide of refuse solid fuel (RDF dry-distilled carbide)
The adsorption and collection experiments of chlorine-based hydrocarbon compounds in the combustion exhaust gas were carried out. In addition, dry distillation charcoal (::
(RDF carbonized carbonized) is the refuse solid fuel obtained by crushing, shaping, and drying combustible materials selected from municipal waste.
A dry-distilled carbide produced by dry-distilling at 700 ° C. was used.

FIG. 7 is a longitudinal sectional view of the adsorption / collection experiment apparatus used in this embodiment. In FIG. 7,
2. Carbonized carbonized waste solid fuel (RDF carbonized carbonized),
4 is a clean gas, 12 is a valve, 60 is a moving bed type adsorption / collector, 61 is a flue of a refuse incinerator, 62 is a suction pump, 63 is a water column manometer, 64A and 64B are gas sampling nozzles, 65
Is a hopper for supplying RDF dry-distilled carbide, 66 is a gas meter (gas flow meter), 67 is a hopper for extracting RDF dry-distilled carbide, 68
A, 68B are sluice valve (sluice valve), f ₄ indicate the flow direction of the combustion exhaust gas.

The adsorber / collector 60 was made of a transparent acrylic resin so that the position of the upper end surface of the RDF dry-distilled carbide 2 filled therein could be visually confirmed. In the present embodiment, the combustion exhaust gas was extracted from the flue 61 by the suction pump 62 and circulated to the adsorption / collector 60. Further, after the combustion exhaust gas flows through the adsorption / collection unit 60, when the gas pressure difference between the gas inlet side and the gas outlet side of the adsorption / collection unit 60 read by the water column manometer 63 increases by 10 mm, the suction pump 62 Stopped.

Next, the gate valve 68B is opened, and the adsorber / collector is opened.
After extracting half of 60 RDF carbonized carbonized carbides, gate valve 68B
Was closed, the gate valve 68A was opened, and new RDF carbonized carbide was supplied from the hopper 65 so that the position of the upper end surface of the RDF carbonized carbonized material 2 of the adsorption / collector 60 was the same as the position before extraction. On the other hand, when the combustion exhaust gas flows through the adsorption / collection unit 60, the gas is continuously sampled from the gas sampling nozzles 64A and 64B on the inlet side and the exit side of the adsorption / collection unit 60 by the following method. The dioxin content in the gas was measured.

[Gas sampling method, measuring method of dioxins content:] (Gas sampling method :)
The gas fraction was collected by the "filtration collection method" according to 8808, and the gas part was collected by the "adsorption collection method" after connecting the adsorption column after collecting dust. (Measurement method of dioxin content :) A gas sample is obtained by subjecting the sample (filtering material, adsorbent, washing solution in the collecting device) obtained above to an acid treatment and a solvent extraction, and then performing a cleanup treatment to obtain a liquid sample. Analysis was performed by mass spectrometry (GC-MS).

The dioxins to be analyzed include PCDD (polychlorodibenzoparadioxin) and PCDD.
All isomers for quantification of DF (polychlorodibenzofuran) and co-PCB (coplanar PCB) were used. As a result,
When the content of dioxins (isomers to be quantified) in the gas at the inlet side of the adsorption / collection unit 60 is 100, the adsorption / collection unit 60
The content of dioxins (isomers to be quantified) in the gas at the outlet side was 5.

That is, according to the present invention, it was found that dioxins in exhaust gas can be removed with high efficiency. As described above, the examples have been described.According to the present invention, boilers, kilns, refuse incinerators, harmful substances such as dioxins in unburned gas in exhaust gas generated in iron scrap melting furnaces such as electric furnaces, By effectively removing and using the carbonized carbonized solid fuel after use as a reducing agent for various fuels or metal oxide-containing substances such as iron ore,
Industrial waste can be effectively used for both environmental conservation and energy and resource conservation.

Further, according to the present invention, the following excellent effects can be further obtained by forming the dry-distilled carbide layer of the solid waste fuel into a fixed bed, a moving bed and a fluidized bed. (1) In the case of the fixed bed: The dry-distilled carbide layer of the refuse solid fuel has the function of both an adsorbent and a filter, and has a gaseous unburned portion, a particulate unburned portion,
Since the metal fine particles and the metal oxide fine particles can be removed by the same processing equipment, the exhaust gas cleaning equipment can be simplified.

Since the filter function can also collect non-adsorptive particulate unburned components in the exhaust gas, by using the dry-distilled carbide of the used refuse solid fuel containing the particulate unburned components as a fuel or a reducing agent. And further energy and resource savings can be achieved. (2) In the case of a moving bed: The same operation and effect as in the case of the fixed bed described above can simplify the exhaust gas cleaning equipment.

Since new dry-distilled carbides are successively supplied, harmful substances in the exhaust gas can be more effectively adsorbed and removed, and continuous operation becomes possible. Since only one adsorption / collection device is required, the exhaust gas cleaning equipment can be downsized. Non-adsorbable particulate unburned components in exhaust gas can also be collected by the filter function, so further energy savings can be achieved by using dry-distilled carbonized solid waste fuel containing particulate unburned components as fuel or reducing agent.・ Resource saving can be achieved.

(3) In the case of a fluidized bed: the particles of the carbonized carbonized carbon that have adsorbed harmful substances and have deteriorated performance are selectively moved to the bottom in the adsorber / collector due to the increase in their density, and are selectively carried out. Since it is discharged from the adsorber / collector, the RDF carbonized carbonized carbon can be used very efficiently as an adsorbent, and continuous operation is possible.

Further, the adsorbing / collecting agent used in the present invention is:
Because it is a dry-distilled carbide of refuse solid fuel that does not involve special treatment such as activated carbon such as steam activation, it is easy to manufacture, and the present invention is easy to apply as an industrial exhaust gas purification method and purification equipment. is there.

[0070]

According to the present invention, harmful substances in exhaust gas such as unburned components in combustion exhaust gas are effectively removed,
Industrial waste can be effectively used for both environmental conservation and energy and resource conservation. Further, according to the present invention, the following excellent effects can be further obtained by forming the dry-distilled carbide layer of the refuse solid fuel into a fixed bed, a moving bed, and a fluidized bed.

(1) In the case of a fixed bed: Exhaust gas cleaning equipment can be simplified. Non-adsorbable particulate unburned components in exhaust gas can also be collected by the filter function, so further energy savings can be achieved by using dry-distilled carbonized solid waste fuel containing particulate unburned components as fuel or reducing agent.・ Resource saving can be achieved.

(2) In the case of a moving bed: The exhaust gas cleaning equipment can be simplified. The harmful substances in the exhaust gas can be more effectively adsorbed and removed, and continuous operation is possible. Exhaust gas cleaning equipment can be downsized.

The filter function can also collect non-adsorbable particulate unburned components in the exhaust gas. Therefore, by using the dry-distilled carbide of the used solid fuel containing the particulate unburned components as a fuel or a reducing agent. And further energy and resource savings can be achieved. (3) In the case of a fluidized bed: the carbonized carbonized solid fuel is efficiently used as an adsorbent, and continuous operation is possible.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an example of a fixed bed type exhaust gas cleaning equipment according to the present invention.

FIG. 2 is a longitudinal sectional view showing an example of a moving bed type exhaust gas cleaning equipment of the present invention.

FIG. 3 is a longitudinal sectional view showing an example of a fluidized bed type exhaust gas cleaning equipment according to the present invention.

FIG. 4 is a longitudinal sectional view showing an adsorption / collection experiment apparatus.

FIG. 5 is a graph showing the relationship between the specific surface area of various carbides and graphitized materials and the amounts of adsorption and collection.

FIG. 6 is a graph showing the relationship between the porosity of various carbides and graphitized materials and the amount of adsorption and collection.

FIG. 7 is a longitudinal sectional view showing an adsorption / collection experiment apparatus (moving bed type).

[Explanation of symbols]

1A, 1B Fixed bed type adsorption / collector 2 Dry carbonized char of refuse solid fuel (: RDF dry carbonized) 3 Exhaust gas 4 Clean gas 5, 5A, 5B Hopper 6A, 6B, 6C belt conveyor 7 for supplying RDF dry carbonized char Hopper for storing RDF dry-distilled carbide after use 8 Exhaust gas supply pipe 9 Clean gas discharge pipe 10 Exhaust air 11 Supply device (rotary valve) for dry-distilled carbide (RDF dry-distilled carbide) of garbage solid fuel 12, 12, 12A, 12B valve 13 , 14 Dry distillation char (RDF dry distillation carbide) of solid fuel from refuse (Rotary valve) 20 Adsorber / collector of moving bed type 21 Gas pressure loss measuring device 22A Control device (Emission control device) 22B Control device ( Supply amount control device) 23 RDF dry carbonized carbon level meter 24A Analyzer for exhaust gas on the inlet side of adsorption / collector 24B Analyzer for clean gas on the outlet side of adsorption / collector 25 Exhaust gas purification rate calculator 26 ₁ , 26 ₂ , 26 ₃ , 26 ₄ , 3 8 _1, 38 _2, 38 _3, 38 ₄ measurement, analysis, calculation result of the signal 26 _5, 38 ₅ control signal 30 adsorbent-collector 31 the dispersion plate in the fluidized bed method (: perforated plate) 32 fine of RDF carbonization carbide 33 Cyclone 34 RDF carbonized carbide circulation pipe 35 RDF carbonized carbide supply pipe valve 36 Valve opening control device 37 RDF carbonized carbide supply pipe 40 Sample 41 Wire mesh basket for holding sample 42 Incense stick (: simulated fuel) 43 Electric heater 44 Support 44a Support pedestal 45 Fishing line 46a, 46b High-sensitivity balance 47 Rubber seal member 48 Suction / collection chamber 49 Combustion chamber 50, 62 Suction pump 51 Combustion air supply pipe 52 Combustion exhaust gas supply pipe 53 Vibration isolator 54 Casing 60 Adsorber / collector (moving bed type) 61 Flue of refuse incinerator 63 Water column manometer 64A, 64B Gas sampling nozzle 65 Hopper for supply of RDF carbonized charcoal 66 Gas meter 67 For extraction of RDF carbonized charcoal Hopper 68A, 68B Gate valve (Sluice valve F ₁ Direction of movement of RDF dry distillation carbide f ₂ , f ₄ Flow direction of flue gas f ₃ Flow direction of combustion air

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Hiroyuki Uesugi 2-3-2 Uchisaiwai-cho, Chiyoda-ku, Tokyo Kawasaki Steel Corporation (72) Inventor Yutaka Yamauchi 1-chome Mizushima Kawasaki-dori, Kurashiki-shi, Okayama Prefecture F) Term in Mizushima Works of Kawasaki Steel Corporation (reference) 4D002 AA21 AC01 AC04 BA04 BA14 CA07 CA08 CA09 DA41 HA01 4H012 HA00 4H015 AA01 AA02 BA13 CB01

Claims (3)

[Claims] 1. A method for purifying exhaust gas, comprising flowing the exhaust gas to a dry distillation carbide layer of refuse solid fuel. 2. The method according to claim 1, wherein the dry-distilled carbide layer of the solid waste fuel is a fixed bed, a moving bed or a fluidized bed. 3. A moving bed type adsorber / collector (20) filled with dry distillation char of refuse solid fuel, and an exhaust gas supply pipe (8) connected to a lower part of the adsorber / collector (20). A clean gas discharge pipe (9) connected to the upper part of the adsorption / collector (20);
A device (11) for supplying a dry-distilled carbide of refuse solid fuel disposed above the adsorption / collection device (20), and the adsorption / collection device (20)
An exhaust device (13) for dry-distilled carbides of refuse solid fuel disposed at the lower part of the device, a gas pressure loss measuring device (21) on the gas inlet side and gas outlet side of the adsorption / collector (20), Level meter (23) for carbonized carbonized solid fuel in garbage in the adsorber / collector (20)
And a control device (22A) that controls the discharge speed of the discharge device (13) based on the measurement result of the gas pressure loss measurement device (21).
And the supply device based on the measurement result of the level meter (23)
An exhaust gas purifying facility comprising a control device (22B) for controlling the supply speed of (11).