JP4323726B2 - Apparatus and method for separating pyrolysis residue - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a pyrolysis residue separation apparatus, and more particularly, to a detection method and a separation apparatus for a large incombustible material suitable for separating large incombustible materials from waste pyrolysis residue.
[0002]
[Prior art]
A waste treatment apparatus described in Japanese Patent Publication No. 6-56253 is known as one of the treatment systems for industrial waste including general waste such as municipal waste and combustibles such as waste plastic.
[0003]
In this example, the waste is put into a pyrolysis reactor and heated in a low oxygen atmosphere below atmospheric pressure for pyrolysis to produce dry distillation gas and pyrolysis residue mainly composed of non-volatile components. After the cracking residue is cooled, the combustible material mainly composed of pyrolytic carbon is separated, the separated combustible material and the dry distillation gas are introduced into a combustion melting furnace and subjected to combustion treatment, and the resulting combustion ash is molten slag. No, this molten slag is discharged and solidified by cooling.
[0004]
At this time, the pyrolysis residue discharged from the pyrolysis reactor includes, for example, rubble such as metals, ceramics, gravel or concrete pieces, or 100 mm or more in addition to the above combustible material mainly composed of pyrolytic carbon. A relatively large incombustible material is mixed.
[0005]
If such a large incombustible material is to be treated by equipment devices arranged at the subsequent stage of the pyrolysis reactor, there is a disadvantage that these devices become large. Therefore, it is necessary to remove this large incombustible material at an early stage, and the present applicants disclosed a large incombustible material separation apparatus in Japanese Patent Application Laid-Open No. 11-325422.
[0006]
In order to separate large incombustibles from small incombustibles, a cantilever spiral sieve is connected to the rear stage of the horizontal rotary drum, which is a thermal decomposition reactor, and the pyrolysis residue discharged from the horizontal rotary drum The small one of the spiral sieves falls from the gap (pitch) of the spiral, and the large incombustible material is transferred to the spiral tip as the spiral rotates, and is discharged from the large incombustible material discharge port. It is like that.
[0007]
[Problems to be solved by the invention]
The environment in which the spiral sieve is installed is about 400 to 500 ° C. and is filled with combustible powders such as carbon and tar. Therefore, it is necessary to block air and the water concentration is 10%. It is in an inferior environment of more than%.
[0008]
Also, since leakage of carbon and pyrolysis residue leads to energy loss, in the above example, a damper is installed at the large incombustible discharge port, and the damper is opened only when large incombustible is discharged. It has become.
[0009]
Therefore, a transmitter and a receiver are arranged at a fixed height on both sides of the spiral sieve, microwaves are emitted from one side so as to cross the rotation axis of the spiral sieve, and the obstruction becomes a transmitter and a receiver. By opening and closing the damper, a large incombustible material with a certain height or more is sensed by a reaction across the space.
[0010]
However, the rotating spiral member of the spiral sieve blocks microwaves, and the atmosphere around the spiral sieve is filled with powder such as carbon and tar as described above, and this is the sensor surface or front surface. A malfunction occurred in which a detection signal was transmitted even though there was no large incombustible between the sensor transmission and reception. As a result, the damper opens unnecessarily, resulting in problems such as air mixing and energy loss.
[0011]
The object of the present invention is to solve the above-mentioned problems and reliably detect large incombustibles in the pyrolysis residue discharged from the pyrolysis drum in a waste treatment system or the like in a poor environment. It is to sort.
[0012]
In order to solve the above-mentioned problem, the present invention uses a reflection type microwave sensor in a waste treatment system, and a spiral rotating shaft toward a pyrolysis residue transferred from the tip of the spiral sieve. When a large incombustible material was detected by emitting microwaves in parallel and detecting a reflected wave, the open / close damper was opened to drop the large incombustible material onto the large incombustible material discharge chute.
[0013]
The microwaves emitted in the direction parallel to the rotation axis go straight without being blocked by the spiral member. Therefore, a large incombustible material can be reliably detected by the reflected wave. In addition, since the sensor is installed in a reflection type, one place is sufficient, and a conventional malfunction can be eliminated with a simple configuration.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic sectional side view of a thermal decomposition residue separation device connected to the latter stage of the thermal decomposition reactor, and FIG. 2 is a view taken along the line AA in FIG.
[0015]
As shown in FIG. 1, in the separation apparatus 51 connected to the rear stage of the thermal decomposition reaction drum 50, a discharge cylinder 52 for discharging the thermal decomposition residue is provided in the horizontal rotary drum that is the thermal decomposition reactor, and the discharge is performed. A spiral sieve 53 is installed extending from the cylindrical body 52.
[0016]
The spiral sieve 53 and the discharge cylinder 52 are rotated on a coaxial core according to the rotation of the thermal decomposition reaction drum 50. In the present example, the spiral sieve 53 is a cantilever type.
[0017]
Of the pyrolysis residue discharged from the pyrolysis reaction drum 50, combustible materials, ash, and small incombustible materials fall from the gaps of the spiral sieve 53, and the large incombustible material 54 rotates at the tip of the spiral as the spiral rotates. Be transported. A damper 55 is provided at the tip of the spiral sieve 53, and a large incombustible material discharge chute 56 is installed through the damper 55.
[0018]
In the present embodiment, a sensor 57 that transmits and receives microwaves is arranged in the direction of the tip of the spiral sieve 53. A large incombustible material was confirmed by emitting a microwave from the sensor 57 substantially parallel to the rotational axis of the spiral sieve and receiving a reflected wave from the large incombustible material 54.
[0019]
FIG. 2 is a view of the inside of the spiral sieve 53 as seen from the sensor 57. It is assumed that the spiral sieve 53 is rotating in the direction of the arrow 58 in the drawing. In this case, the direction in which the microwave is emitted is within the area 59 indicated by the dotted line in the drawing. This is because the large incombustible material shifts in the rotational direction due to the rotation of the spiral.
[0020]
In the present invention, since microwaves are emitted from the direction of the rotation axis of the spiral sieve toward the inside of the spiral sieve, the microwaves are not blocked by the spiral. Therefore, reliable sensing is possible and malfunctions are prevented.
[0021]
Next, with reference to FIGS. 3 to 5, some embodiments of the microwave sensor integrated with transmission and reception applied to the sorting apparatus of the present invention will be described. These sensors 60 have a double tube structure including an inner tube 61 formed of a transmission / reception type microwave sensor and an outer tube 62 protecting the inner tube 61.
[0022]
As described above, the inside 63 of the separation device is a poor environment in which a high dust atmosphere is filled with a combustible gas, the temperature is 300 to 500 ° C., the water concentration is 10% or more, and the tar content is mixed with a high concentration. ing. Therefore, there is a problem that carbon, water, tar and the like adhere to the sensor surface and cause malfunction.
[0023]
FIG. 3 is a cross-sectional configuration diagram of the transmission / reception integrated sensor 60. The sensor 60 of this example blows the purge gas 64 flowing between the inner tube 61 and the outer tube 62 from the periphery of the transmission / reception surface 65 of the transmission / reception type microwave sensor to the transmission / reception surface 65 so as to maintain a clean state. I made it.
[0024]
As the purge gas, an inert gas such as nitrogen (N ₂ ) gas is used, and a flow rate of 10 to 30 (m / S) is appropriate. Further, it is preferable that the purge gas 64 is continuously blown during operation of the sorting apparatus. Further, steam (superheated steam) can be used as the purge gas.
[0025]
The example shown in FIG. 4 is an example in which the purge gas outflow opening provided around the sensor transmission / reception surface 65 has a slit shape. 4A is a cross-sectional configuration diagram of the sensor, and FIG. 4B is a BB arrow view.
[0026]
In this example, a slit ring 66 is attached around the transmission / reception surface 65 of the sensor 60. The slit ring 66 is formed by forming a slit hole 67 in a ring-shaped metal piece. Compared to the example of FIG. 3, the outflow opening of the purge gas 64 is a pore, so the outflow rate is high and the purge gas amount is also economical.
[0027]
The example shown in FIG. 5 is an example in which the slit ring 66 in the example of FIG. Fig.5 (a) is a cross-sectional block diagram of a sensor, FIG.5 (b) is the CC arrow directional view.
[0028]
In this example, the arc-shaped slit ring 68 is installed on the upper part of the transmission / reception surface 64, and the lower part is processed so that there is no portion protruding from the transmission / reception surface 64. By doing so, there is no dust accumulation in which carbon or the like accumulates, which is extremely advantageous in terms of maintenance such as cleaning. The upper part may be any of an arc shape, a half shape, a half circumference shape, and the like.
[0029]
Next, still another embodiment of the transmission / reception integrated microsensor will be described with reference to FIG. In the transmission / reception type microwave sensor 70 of this example, the gaps and cavities of the transmission / reception unit 71 are filled with ceramics 72 that transmits microwaves. The ceramic 72 is a ceramic having good heat resistance, corrosion resistance, and insulating properties, and examples thereof include Al ₂ O ₃ , MgO, and SiN.
[0030]
FIG. 6B shows an embodiment of the present invention, in which the transmitter / receiver 71 of the sensor is filled with ceramics 72 without a gap. The transmission / reception surface 73 is also configured with the filled ceramic as it is, without attaching another member. In this example, a stainless steel case 74 filled with ceramics is used, but ceramics may be used without a case.
[0031]
FIG. 6A is a perspective view of a comparative example of the present invention, in which a funnel-shaped transmission / reception unit 71 is a hollow sensor formed of stainless steel, and a ceramic plate 74 is attached to the transmission / reception surface 73. . In this comparative example, there is a possibility that dust or moisture may enter the cavity of the transmission / reception unit from the gap of the ceramic plate mounting portion and cause malfunction.
[0032]
The spiral sieve is selected according to the size and properties of the pyrolysis residue to be separated, and is formed in a spiral shape at a constant interval or an appropriate pitch interval (100 to 500 mm in this example) changed in the longitudinal direction. . Moreover, it is formed in the helical shape with the same diameter toward the tip or gradually increasing in diameter.
[0033]
Next, a waste disposal system provided with a sorting device according to the present invention will be described. FIG. 7 is a system diagram showing an example of a waste treatment system. Waste a including combustibles such as municipal waste is supplied to the thermal decomposition reactor 2 via the waste supply device 1.
[0034]
The inside of the thermal decomposition reactor 2 is maintained in a low oxygen atmosphere, and heated air b heated to 500 to 550 ° C. by a high-temperature air heater disposed on the downstream side of the combustion melting furnace 17 is converted into a line L1. To the heat transfer tube of the pyrolysis reactor 2.
[0035]
The waste supplied into the pyrolysis reactor 2 by this high-temperature heated air is heated to 300 to 600 ° C., usually about 450 ° C., and pyrolyzed to produce mainly non-volatile pyrolysis residue. A pyrolysis gas (dry distillation gas) G1 is generated. The pyrolysis gas G1 is supplied to the combustion melting furnace 17 via a line L2.
[0036]
By the way, the pyrolysis residue discharged from the pyrolysis reactor varies depending on the type of waste, but in the case of municipal waste in Japan, according to the knowledge of the present inventors,
Most combustibles with relatively fine particles 10-60%
5-40% relatively fine ash
Coarse-grained metal component 7-50%
Coarse-grained rubble, pottery, concrete, etc. 10-60%
It has been found that it is composed.
[0037]
In order to reliably remove relatively large incombustible materials of 100 mm or more, such as debris such as metal, ceramics, gravel, or concrete pieces, from the pyrolysis residue of the present invention, Special devices were applied to the separation device 6 connected to the subsequent stage.
[0038]
That is, as shown by A in FIG. 7, the sorting device 6 of the present system includes a spiral sieve 7 and a transmission / reception integrated microsensor 9, and large incombustible materials detected by the sensor 9 are discharged via a damper 8 to a discharge chute 10. To discharge from.
[0039]
As described above, from the large pyrolysis residue transferred to the large incombustible material discharge chute 10 side, combustible material that has been pyrolyzed and pulverized in the pyrolysis reactor 2 is already present in the spiral sieve 7. Since it has been removed, it is mostly composed of non-combustible materials such as metal and rubble.
[0040]
On the other hand, the pyrolysis residue composed of fine particles or relatively small-diameter particles falls from the pitch gap of the spiral sieve 7, and the fallen pyrolysis residue c1 is a combustible substance, ash, and small size in the waste a. It consists of nonflammable materials such as rubble.
[0041]
The fallen pyrolysis residue c1 is supplied to the cooling device 19, where it is cooled to a temperature at which there is no risk of oxidation, for example, about 80 ° C., and then separated into small incombustible material d and combustible material e in the separation device 20. Separated.
[0042]
The combustible material e is pulverized to a fine powder of, for example, 1 mm or less in the pulverizer 21, and the pulverized combustible component e1 is supplied to the burner 18 of the melting furnace 17 via a line L3. The melting furnace 17 is further supplied with the dry distillation gas G1 from the line L2 and the combustion air f from the line L4 by the forced blower 22 via the burner 18.
[0043]
The combustible component e1 is combusted in the high temperature range of about 1,300 ° C. in the melting furnace 17 by the dry distillation gas G1 and the combustion air f, and is mixed in the combustion ash generated at this time and the combustible component e1. The ash content is melted and becomes molten slag g which falls into the water tank 23 and is cooled and solidified.
[0044]
The combustion gas G2 in the melting furnace 17 is recovered from the line L5 by an air heater (not shown) and a waste heat boiler 24, removed by a dust collector 25, and cleaned by a gas cleaning device 26. Most of the exhaust gas G3 is discharged from the chimney 27 as clean low-temperature exhaust gas G3.
[0045]
The steam S obtained by the waste heat boiler 24 is used for power generation by the power generator 28. An induction blower 29 is installed on the front side of the chimney 27. Moreover, the sealing mechanisms 30 and 31 for maintaining the low oxygen atmosphere in the sorting apparatus 6 are configured by, for example, a double gate valve.
[0046]
As described above, according to the present embodiment, by irradiating the transmission / reception integrated microsensor from the direction of the spiral rotation axis, the microwave is not blocked by the rotating spiral member, and even in a poor environment, Large incombustibles can be detected reliably. In the above example, microwaves are used, but light, ultrasonic waves, or lasers can also be used.
[0047]
【The invention's effect】
As described above, according to the present invention, in the separation apparatus connected to the rear stage of the pyrolysis rotary drum such as a waste treatment system, the transmission / reception integrated microsensor is arranged in the direction of the tip of the spiral sieve, and the spiral rotation shaft and Large incombustibles can be reliably taken out by emitting microwaves in the spiral substantially in parallel and detecting the reflected waves.
[0048]
Therefore, it is possible to prevent air leakage and pyrolysis gas from leaking due to malfunction, and to prevent the large incombustible material from being removed and staying in the waste treatment system.
[Brief description of the drawings]
FIG. 1 is a cross-sectional configuration diagram showing an embodiment of a sorting apparatus according to the present invention.
FIG. 2 is a view taken in the direction of arrows AA in FIG.
FIG. 3 is a cross-sectional configuration diagram showing a first example of a transmission / reception integrated microsensor according to the present invention.
FIG. 4 is a cross-sectional configuration diagram illustrating a second example of a transmission / reception integrated microsensor according to the present invention.
FIG. 5 is a cross-sectional configuration diagram showing a third example of a transmission / reception integrated microsensor according to the present invention.
FIG. 6 is a perspective view showing another example of a transmission / reception integrated microsensor according to the present invention.
FIG. 7 is a system diagram of a waste treatment system including a sorting device according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Waste supply apparatus 2 Pyrolysis reactor 6 Separation apparatus 7 Spiral sieve 8 Damper 9 Transmission / reception integrated microsensor 10 Discharge chute 17 Melting furnace 50 Pyrolysis rotary drum 51 Separation apparatus 52 Discharge cylinder 53 Spiral sieve 54 Large incombustible material 55 Damper 56 Discharge chute 57, 60 Transmission / reception integrated microsensor 63 Inside of sorting apparatus 64 Transmission / reception surface 66 Slit ring 68 Arc-shaped slit ring 70 Transmission / reception type microwave sensor 71 Transmission / reception unit 72 Ceramics 73 Transmission / reception surface

Claims (5)

It is connected to the rear stage of the pyrolysis reactor that thermally decomposes waste to produce dry distillation gas and pyrolysis residue, and rotates to drop combustibles, ash, and small incombustibles. A spiral sieve that transfers a large incombustible material to the tip, and a microwave that is disposed at the tip of the spiral sieve, emits microwaves in the direction of the transferred large incombustible material, and receives the reflected wave to remove the large incombustible material. A sensor for detecting, and a large incombustible discharge chute installed through an open / close damper for discharging the large incombustible transferred to the tip of the spiral sieve, wherein the large incombustible is detected by the sensor. A device for separating pyrolysis residue, wherein the open / close damper is opened when the open / close damper is opened .   The sensor includes an inner tube composed of a transmission / reception type microwave sensor and an outer tube that protects the inner tube, and purge gas is applied to the transmission / reception surface of the transmission / reception type microwave sensor from between the inner tube and the outer tube. The sorting device according to claim 1, wherein the sorting device is made to flow.   The sorting device according to claim 1, wherein the sensor is formed by filling a cavity or a gap in a transmission / reception unit of a transmission / reception type microwave sensor with ceramics through which microwaves are transmitted. Pyrolysis residue obtained by pyrolyzing waste is sent to a rotating spiral sieve installed almost horizontally to drop combustibles, ash and small incombustibles, and large incombustibles to the tip of the spiral sieve. In the method for separating pyrolysis residues to be dropped onto a large incombustible discharge chute installed via an open / close damper for discharging and discharging a large incombustible, the large incombustible transferred from the tip of the spiral sieve A method for separating pyrolysis residues by receiving a reflected wave of a microwave emitted in the direction of and opening the open / close damper when the large incombustible material is detected.   A pyrolysis reactor for heating and decomposing waste to produce pyrolysis gas and a pyrolysis residue mainly composed of non-volatile components, and a non-combustible component of the pyrolysis residue, And a combustion melting furnace for combusting a combustible component of the pyrolysis residue and the pyrolysis gas to generate molten slag and combustion exhaust gas. A waste treatment system, wherein the sorting device is the sorting device according to any one of claims 1 to 3.

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