JPH1054540A - Combustion melting furnace with slag removal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily remove solidified slag by providing a slag removal device comprising a slag removal head having a shape such that the head can be inserted into a slag discharge port and a drive means. SOLUTION: Exhaust gas near a slag discharge port 5 has a temperature equal to or higher than the melting point of slag. However, water in a water tank 7 has a low temperature of, for example, 60-70 deg.C, and hence the temperature of molten slags 16, 19 reaching the edge 17 of the port 5 falls by radiational cooling and fluidity of the surface of a slag flow decreases so that the slags are solidified. And the solidified slags 18, 18 grow, and hence the port 5 is easily closed. Hence, when solidified slags 18, 18 grow, a cylinder is driven to extend a cylinder axis 13 so that a slag removal head 15 is lowered to insert it into the port 5, whereby the slags 18, 18 solidified on the edge 17 of the port 5 are pushed down by the head 15 and broken or separated from the edge 17 so as to be dropped into the tank 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion melting furnace for burning a pyrolysis gas obtained by pyrolyzing wastes and the like, and more particularly to an apparatus for scraping off slag solidified at a slag discharge port of the combustion melting furnace. About. Wastes here include combustible materials such as general waste such as municipal waste from homes and offices, waste plastic, car shredder dust, waste office equipment, electronic equipment, and industrial waste such as chemical products. Including.

[0002]

2. Description of the Related Art Various types of waste treatment apparatuses for treating various wastes such as general waste such as municipal waste and industrial waste such as waste plastic by incineration and the like have been proposed. I have. For example, according to the waste treatment apparatus described in Japanese Patent Publication No. 6-56253, first, waste is thermally decomposed by heating it in a low oxygen atmosphere, and then gas and solid (hereinafter, referred to as pyrolysis residue). The pyrolysis gas is led to a combustion melting furnace for combustion treatment, and the combustion waste heat is recovered by a waste heat boiler. On the other hand, the pyrolysis residue is appropriately separated into components according to the size, such as fine fine-grained components, slightly fine coarse-grained components, and slightly coarse coarse-grained components, by a separation device such as a sieve. Then, the pyrolysis residue composed of the fine-grained component and the slightly fine-grained component is sent to the above-mentioned combustion melting furnace and incinerated with the pyrolysis gas. Most of the combustion residues generated in this incineration process, that is, most of the non-combustible components such as ash, are melted by combustion heat to become molten slag. Most of the incombustible fly ash carried along with the pyrolysis gas is also melted by the heat of combustion in the combustion melting furnace to become molten slag. This molten slag is discharged from the bottom of the combustion melting furnace and solidified by cooling. On the other hand, fine incombustible components (hereinafter referred to as dust) such as fly ash which are not melted in the combustion melting furnace and are discharged together with the combustion exhaust gas are, for example, waste heat disposed in the latter stage of the combustion melting furnace. The collected dust is collected in a boiler, an exhaust gas cooling tower, an exhaust gas filtering device, or the like, and the collected dust is returned to the combustion melting furnace, mixed with the molten slag, and solidified. In other words, the fine component or relatively fine coarse component of the pyrolysis residue, and dust such as fly ash collected by an exhaust gas filtration device are melted in a combustion melting furnace, and then cooled and solidified. By this, it is formed into a shape that can be easily handled.

[0003]

However, in the above-mentioned waste treatment apparatus, the molten slag discharged from the combustion melting furnace (having a melting temperature of about 1300 ° C.) is supplied from the slag discharge port provided at the furnace bottom to the water tank. The temperature near the slag outlet is the water tank temperature (about 60 to 8).
0 ° C), the temperature is lower than in the furnace. Therefore, the temperature of the molten slag that has reached the slag discharge port is reduced by radiant cooling, and solidified slag may grow at the edge of the slag discharge port, thereby causing a problem that the slag discharge port is blocked.

As a method of removing the solidified slag generated at the edge of the slag discharge port, a maintenance hole is provided on a side wall of a discharge nozzle extending downward at the slag discharge port, and an iron rod or the like is formed through the hole. It is conceivable that the solidified slag formed at the edge of the slag discharge port is removed from below by peeling or smashing the solidified slag formed at the edge of the slag discharge port.

[0005] However, there is a problem that it is labor intensive to beat and break it by hand, and there is a problem that workability is poor, such as a large lump of slag falling into a water tank, which produces severely water vapor.

An object of the present invention is to improve the operation of removing solidified slag at a slag outlet of a combustion melting furnace.

[0007]

SUMMARY OF THE INVENTION The present invention provides a slag removing apparatus comprising a slag removing head which can be inserted into a slag discharge port, and a driving means for inserting and removing the slag removal head from above into the slag discharge port. With the provision, the above-mentioned problem is solved. That is, when the solidified slag has grown in the slag discharge port, the solidified slag can be easily removed by operating the driving means and inserting the slag removal head into the slag discharge port.

In this case, the slag discharge port is provided at the bottom of the flue drawn laterally from the bottom of the combustion melting furnace, and the space for accommodating the slag removal head at the upper surface position facing the slag discharge port of the flue. Is preferably provided. It is preferable that a drive cylinder is arranged outside the top of the space, the shaft of the drive cylinder is inserted into the flue, and the slag removing head is attached to the tip, thereby forming a drive device. By the way, since the exhaust gas temperature in the flue near the slag discharge port is about 1300 ° C. or more, it is desirable to provide a cooling water passage through which cooling water is circulated in the slag removing head and the cylinder shaft to cool.

In addition, instead of the driving means using a cylinder, a drum is rotatably mounted inside the top of the space,
A chain may be wound around the drum, a weight serving as a slag removing head may be attached to the end of the chain, and operating means for rotating and stopping the drum from outside may be provided. According to this, the solidified slag can be easily removed by the weight of the slag removing weight.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a sectional view of a combustion melting furnace of one embodiment provided with a slag removing device of the present invention. As shown in the figure, in the combustion melting furnace 1, a burner 3 is attached to the furnace top of a hollow furnace body 2, and a flue 4 of the combustion exhaust gas is drawn out from the furnace bottom in a lateral direction. A slag discharge port 5 is provided, a slag discharge cylinder 6 extends downward from the slag discharge port 5, and a tip of the slag discharge cylinder 6 is disposed so as to be submerged below a water surface 8 of a water tank 7. A heat-resistant material 9 is provided on the inner surfaces of the furnace body 2, the flue 4, the slag discharge cylinder 6, and the like.

A single pipe 10 having a substantially same opening shape as the slag discharge port 5 and forming a space having a predetermined depth is attached to an upper surface position of the flue 4 facing the slag discharge port 5.
A cylinder mounting seat 11 is mounted on the upper end of the single pipe 10 via a flange. A hydraulic or pneumatic cylinder 12 is fixed by inserting a cylinder shaft 13 into a through hole formed in the center of the mounting seat 11. The through hole of the cylinder shaft 13 is hermetically sealed by a sealing means 14, and a slag removal head 15 is attached to the tip of the cylinder shaft 13. The slag removal head 15 is connected to the slag discharge port 5.
The slag outlet 5 is formed in a shape that is equal to or slightly smaller than the shape of the opening of the slag discharge port 5, and particularly, the side surface of the edge is an inclined surface that is reduced downward. These cylinders 1
2 and the slag removing head 15 and the like form a slag removing device.

Next, the operation of the combustion-melting furnace thus configured will be described focusing on the slag removing device. The pyrolysis gas G supplied to the burner 3 is mixed with the primary air A and blown into the furnace, where it is ignited by a pilot burner (not shown). The pyrolysis gas G usually contains flammable and non-combustible powders generated by pyrolysis, and the flammable powders are burned together with the pyrolysis gas to form the non-flammable powders ( Ash, etc.) are melted by the heat of combustion.
The combustion exhaust gas generated in the combustion melting furnace 1 is discharged through the flue 4. Although not shown, combustible residues and non-combustible residues generated in the course of the thermal decomposition treatment can be put into the combustion melting furnace 1 and burned or melted. Is also melted. The incombustible material thus melted adheres to the furnace inner wall of the combustion and melting furnace 1 to become molten slag 16, flows down the furnace inner wall, reaches the slag discharge port 5 as shown in FIG. It flows down from the edge 17 of the discharge port 5 in the slag discharge cylinder 6 and reaches the water surface 8 of the water tank 7, is rapidly cooled, is appropriately finely divided by the impact of cooling, and is accumulated at the bottom.

Here, the bottom of the flue 4 near the slag discharge port 5 is formed by melting the molten slag 16 with the opening edge 17 of the slag discharge port 5.
Is formed with a change in the height of the bottom surface so as to flow down from one location (preferably the edge on the side of the combustion melting furnace 1) into the water tank. For example, as shown in FIG. 3, a weir 20 is provided around the opening of the slag discharge port 5, a part of the weir 20 on the side of the combustion melting furnace 1 is cut out, and the cutout portion is connected to the slag discharge port 5. A groove 21 having a V-shaped cross section is provided, and the molten slag can flow down from one location into the water tank along the groove 21.

Next, the slag removing operation which is a feature of the present invention will be described. The combustion temperature in the combustion melting furnace 1 is maintained at or above the slag melting temperature (about 1300 ° C.), and the exhaust gas temperature near the slag discharge port 5 is also at or above the slag melting temperature. However, since the temperature of the water in the water tank 7 is a low temperature of, for example, 60 to 80 ° C., the temperature of the molten slag 16 reaching the edge 17 of the slag discharge port 5 is reduced by radiant cooling, and the temperature of the slag flow is reduced. The fluidity may decrease and eventually solidify. In particular, the slag flow tends to solidify when the flow rate of the slag flow is small, and a layer of the solidified slag 18 grows on the edge portion 17, and the slag discharge port 5 may be closed if left unattended. The main stream of the molten slag 16 is:
There is a molten slag 19 flowing down from the furnace side edge of the slag discharge port 5, and a molten slag 19 flowing down from the side surface of the flue 4 at the position of the slag discharge port 5 and the downstream side of the flue 4. 18 may grow and promote the blockage of the slag discharge port 5.

When the solidified slag 18 is formed, the cylinder 12 is driven to extend the cylinder shaft 13,
When the slag removal head 15 is lowered and inserted into the slag discharge port 5, the solidified slag 18 that has grown on the edge 17 of the slag discharge port 5 is pushed down by the slag removal head 15, thereby being broken or removed from the edge 17. It is peeled and falls into the water tank 7. If the slag head 15 cannot be removed at one time, the vertical operation of the slag head 15 is repeated. In this way, by driving the slag removing device periodically or at an appropriate frequency, the solidified slag can be removed and the slag discharge port 5 can be prevented from being blocked.

As shown in the embodiment of FIG. 1, since the slag removing device is provided above the slag discharge port 5, the structure is simpler than when the slag removing device is provided in the discharge cylinder 6 below the slag discharge port 5. Can be In other words, in the case where the slag flow is provided in the discharge cylinder 6, the slag flow is normally retracted to a position where the slag flow is not applied, and moved to a position facing the opening of the slag discharge port 5 in use in order to avoid the slag flow. Is required.

In FIG. 1, when the slag removing head 15 is not used, the flow of the combustion exhaust gas is not hindered by storing the slag removing head 15 in the space formed by the single pipe 10. Further, the slag removal head 15 and the cylinder shaft 13 are provided with the temperature (1
(300 ° C. or higher), for example, SUS301
It is formed using S. Further, as shown in FIG. 4, the slag removing head 15 and the cylinder shaft 13 are integrally formed in a double pipe structure, and as shown by an arrow in the figure, the inner cooling passage 2 is formed.
It is preferable that the cooling water is supplied to the cooling water passage 3 so that the cooling water flows through the hole 24 provided in the head portion to the outside cooling passage 25 to perform circulating cooling.

Further, a timer or the like may be provided in the control device of the cylinder 12 so that the cylinder 12 is driven at regular intervals to automatically remove solidified slag. Alternatively, T is defined as a view range near the edge of the slag discharge port 5.
A solidified slag sensor consisting of a V-camera is attached, image processing is performed to monitor the growth of the solidified slag, and when it is determined that a fixed amount of solidified slag has been formed, the cylinder 12 is automatically driven to remove the solidified slag. can do.

Next, FIG. 5 shows another embodiment of the slag removing apparatus of the present invention. This example is different from the example of FIG.
Weight 3 having sufficient weight in place of slag removal head 15
0 (for example, 20 kg), which is suspended by a chain 31, the chain 31 is connected to a winding drum 32, and the rotation of the winding drum 32 is stopped by a handle 33 provided outside. Then, the slag is inserted into or removed from the slag discharge port 5 to remove the solidified slag. Winding drum 32
Are hermetically and rotatably supported by a seal bearing 34. In addition, it can be stopped at an arbitrary rotation position by a not-shown locking means. Therefore, according to this, the configuration can be simplified as compared with the embodiment of FIG.

Next, with reference to FIG. 6, an embodiment of a waste treatment apparatus to which the above-described combustion melting furnace provided with the slag removing apparatus of the present invention is applied will be described. Waste is, for example, 15
It is pulverized to 0 mm or less, introduced into a rotary drum type pyrolysis reactor 52 by a screw feeder 51, and heated by a heat medium flowing through a plurality of heating tubes provided on the inner wall.
It is heated to about 0 ° C. to 600 ° C. (usually 450 ° C.), thereby being thermally decomposed in a low oxygen atmosphere. Pyrolysis reactor 5
The pyrolysis gas and pyrolysis residue generated in 2
3, the pyrolysis gas is supplied to the burner 3 of the combustion melting furnace 1 through a pipe. After the pyrolysis residue is cooled to about 80 ° C. in the cooling device 54, it is sent to the separation device 55. As the separation device 55, for example, a known separation device such as a sieve, a magnetic separation type, an eddy current type, a centrifugal type or a wind separation type is used, and a flammable powder such as pyrolytic carbon and a non-combustible component are used. Separates into metal components and non-metal components.
The flammable powder contains non-combustible components such as fine ash in addition to the pyrolytic carbon, and is discharged to the hopper 56. Other separated components are discharged to a container or a hopper as appropriate. The powder in the hopper 56 is supplied to the burner 3 of the combustion melting furnace 1 through a pipe.

The structure and operation around the combustion melting furnace 1 are as described with reference to FIG. The high-temperature combustion exhaust gas generated in the combustion melting furnace 1 heats the heating air flowing through the heating pipe of the thermal decomposition reactor 52 by a heat exchanger (high-temperature air heater) (not shown), and then passes through the pipe. And supplied to the waste heat boiler 60. The waste heat boiler 60 generates steam by the heat of the combustion exhaust gas, thereby rotating the steam turbine generator 61 to recover power. The combustion exhaust gas discharged from the waste heat boiler 60 is guided to a dust collector 62 for dust removal and further processed by a gas purification device 63 such as a dechlorination device.
The air is released from the chimney 65 to the atmosphere through the air 4. A part of the combustion exhaust gas is supplied as a cooling medium to the cooling device 54 via a pipe 66.

Although the present invention has been described in detail with reference to the illustrated embodiments, the present invention is not limited to only those embodiments, and various modifications may be made without departing from the spirit of the present invention. It goes without saying that various modifications can be made.

[0023]

As described above, according to the slag removing apparatus of the present invention, the solidified slag formed at the slag discharge port of the combustion melting furnace can be easily removed, and workability can be improved. .

[Brief description of the drawings]

FIG. 1 is a configuration diagram of one embodiment of a combustion melting furnace provided with a slag removing device of the present invention.

FIG. 2 is a diagram illustrating the operation of the slag removing device shown in FIG.

FIG. 3 is a diagram showing an example in which a molten slag weir and a flow-down groove are provided near a slag discharge port.

FIG. 4 is a conceptual diagram illustrating a water cooling structure of a slag removal head.

FIG. 5 is a view showing a configuration of a combustion melting furnace provided with another embodiment of the slag removing device of the present invention.

FIG. 6 is a system configuration diagram of a waste disposal apparatus to which a combustion melting furnace provided with the slag removal apparatus of the present invention is applied.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Combustion melting furnace 3 Burner 4 Flue 5 Slag discharge port 7 Water tank 12 Cylinder 13 Cylinder shaft 15 Slag removal head 16 Melted slag 17 Edge 18 Solidified slag 30 Weight 31 Chain 32 Winding drum 33 Handle

Claims (4)

[Claims] 1. A pyrolysis gas obtained by thermally decomposing waste is burned, and molten slag of incombustible substances generated by the combustion heat is guided to a furnace bottom, and is discharged from a slag discharge port provided at the furnace bottom to the outside. A slag removal device comprising a slag removal head having a shape insertable into the slag discharge port and a driving means for inserting and removing the slag removal head from above in the slag discharge port in a combustion melting furnace formed to discharge the slag. A combustion melting furnace comprising: 2. The combustion melting furnace according to claim 1, wherein
The slag discharge port is provided on a bottom surface of a flue drawn laterally from the bottom of the combustion melting furnace, and a space for accommodating the slag removal head is provided at an upper surface position of the flue facing the slag discharge port. Wherein the driving means has a driving cylinder disposed outside the top of the space, and a shaft of the driving cylinder is inserted into a flue, and the slag removing head is attached to a tip end of the driving cylinder. . 3. The combustion melting furnace according to claim 2, wherein
The slag removing head and a shaft of the cylinder are provided with a cooling water passage through which cooling water is circulated. 4. The combustion melting furnace according to claim 1, wherein
The slag discharge port is provided on a bottom surface of a flue that is laterally drawn from the bottom of the combustion melting furnace, and the slag removal head and the driving unit are housed at an upper surface position of the flue facing the slag discharge port. A space portion is provided, and the driving means includes a drum rotatably mounted inside the top of the space portion, a chain wound around the drum and having the slag removal head mounted at the tip thereof, and A combustion-melting furnace comprising operating means for rotating and stopping.