JP4096013B2 - Granulated slag treatment equipment - Google Patents

Description

  In the ash melting furnace in which the incineration ash such as waste is melted and the incinerated ash converted into slag is recycled or reduced in volume, when the molten slag is granulated, the soil of the granulated granulated slag It is related with the processing apparatus of the granulated slag which can remove.

  The ash melting furnace is intended for effective use of refuse incineration ash, and the incineration ash melted by the ash melting furnace is made harmless by separating it into low boiling point volatilized materials and slag of metals and other components. , We are trying to recycle it. The need for incinerator ash melting furnaces is increasing. FIG. 3 shows a conventional plasma arc ash melting furnace 51 and a granulated slag treatment device 61. The ash melting furnace 51 is provided with a main electrode 52 of a plasma electrode on the furnace chamber side and a furnace bottom electrode 53 on the furnace bottom side. Further, the ash melting furnace 51 is provided with a tap outlet 54 which is a discharge port for molten slag, and a tap tap 55 is connected to the tap outlet 54.

  FIG. 4 shows the vicinity of the tap outlet 54 of the ash melting furnace 51. On the side wall 56 of the ash melting furnace 51, the above-described tap outlet 54 is disposed at a position slightly higher than the furnace bottom wall 57. In the furnace bottom wall 57, slag 70 heated by melting the incineration ash and metal 69 in which the metal components in the incineration ash are melted are accumulated, and the slag 70 accumulated in the bottom of the outlet 54 overflows. This serves to discharge the slag 70. A granulation tank 62 for performing water granulation (water cooling) treatment of the molten slag is disposed below the tip of the brewery 55, and the granulation slag 65 is subjected to the granulation slag treatment from the granulation tank 62 to the granulation tank 62. A granulating conveyor 63 to be transferred to the outside of the apparatus 61 is arranged, and a slag discharge port 64 is arranged on the upper end side of the granulating conveyor 63.

  With such a configuration, when incineration ash is put into the furnace chamber of the ash melting furnace 51 and a voltage is applied to the plasma electrodes 52 and 53, a plasma arc is generated between the electrodes 52 and 53, and the incineration ash is heated. When the molten slag 70 is accumulated at the bottom of the furnace and reaches the height of the outlet 54, the slag overflows from the outlet 54 and flows down to the granulating tank 62 through the outlet 55. A granular granulated slag 65 is obtained. The granulated slag 65 is transferred upward along with the rotation of the granulated conveyor 63 and discharged from the discharge port 64 of the granulated slag 65. At this time, when the cooling water 66 flows down to the molten slag 70, the cooling water 66 evaporates due to the heat of the molten slag 70, and therefore, a water supply port 67 for supplying the cooling water 66 is disposed in the granulating tank 62. ing. On the other hand, the gas generated during the work is discharged from the exhaust port 58 and made harmless by the exhaust gas treatment device provided in the next process.

  As shown in FIG. 4, the upper wall 59 and the exhaust port 58 of the tap 55 in the ash melting furnace 51 are in an environment where the temperature is hardly affected by the plasma heat. Therefore, when the combustion gas comes into contact with these wall portions, the combustion gas reacts to generate a dissolved salt of NaCl and KCl, and heavy metal is transferred from the upper portion of the outlet 54 to the upper wall 59 and the exhaust outlet 58 of the outlet 55. The dissolved salt 71 containing may adhere. The dissolved salt 71 is peeled off from the side wall portion 60 and falls into the cooling water 66, or combustion gas containing heavy metal contacts the cooling water 66 in the granulating tank 62 through the exhaust port 58, and the cooling water 66 is contaminated. May be. The dissolved salt mixed in the cooling water 66 of the granulating tank 62 does not evaporate, and if the operation of the ash melting furnace 51 is continued as it is, the salt concentration in the water rises and adheres to the surface of the granulated slag 65. To do.

  In addition, as shown in FIG. 4, in the ash melting furnace 51, when incinerated ash is supplied onto the molten slag 70, it is not melted on the surface of the molten slag 70 due to fluctuations in the amount of ash supplied and the properties of the ash. The molten incineration ash 72 may float and be discharged from the spout 54. The unmelted incinerated ash 72 is not detoxified, and if it is mixed into the cooling water 66 of the granulating tank 62, the cooling water 66 is contaminated and contaminants adhere to the surface of the granulated slag 65. There is. Therefore, the granulated slag 65 may not clear the elution standard.

  This invention is made | formed in view of such a situation, and when the molten slag of incinerated ash is subjected to a water granulation process to make a granulated slag, the granulated slag can be prevented from being contaminated. An object is to provide a processing apparatus.

In order to achieve the above object, the apparatus for treating granulated slag according to the present invention uses the cooling water in the granulation tank to cool the molten slag discharged from the outlet of the plasma arc ash melting furnace. In the processing apparatus of the granulated slag which crushes and produces | generates granulated slag, and discharges this granulated slag out of the said granulation tank with a conveyor, the said conveyor follows an inclined surface from the bottom part of the said granulation tank. comprises a number of scraping claws moving, the water砕槽bottom can transfer the precipitated granulated slag to a discharge portion positioned at the upper portion of the inclined surface in der Rutotomoni, of the water砕槽in said discharge portion A cleaning spray that injects cleaning water between the upper part of the inclined surface and the conveyor is provided , the granulated slag between the scraping claws can be cleaned, and the cleaning water flows into the granulated tank. I did it.

  As mentioned above, according to the processing apparatus of the granulated slag of this invention, the molten slag discharged | emitted from the slag discharge | emission part of an ash melting furnace is granulated with the cooling water in a granulation tank, and granulated slag is processed. In the processing apparatus of the granulated slag which produces | generates and discharge | emits this granulated slag out of the said granulation tank with a conveyor, the washing spray which wash | cleans this granulated slag with water in the discharge part of the said granulated slag of the said conveyor Since the water of the cleaning spray is supplied into the above-mentioned granulation tank, the granulated slag contaminated in the granulation tank can be washed. Also, a detector for detecting the amount of cooling water in the water tank is provided in the water tank, and the water of the cleaning spray is put into the water tank according to the amount of cooling water in the water tank. Since it was made to replenish, the cooling water in the granulation tank which evaporates when the molten slag is granulated can be supplemented.

  Hereinafter, the processing apparatus of the granulated slag by embodiment of this invention is demonstrated, referring drawings. FIG. 1 shows a plasma arc ash melting furnace 1 according to the present invention. The ash melting furnace 1 is provided with a furnace chamber 6 surrounded by a furnace side wall 11 formed of refractory bricks, on the main electrode 4 disposed on the furnace chamber 6 side, on the furnace bottom wall 5 side of the furnace chamber 6. A plasma apparatus including a furnace bottom electrode 7 to be disposed and a DC power source 8 for supplying electricity to these is provided. The main electrode 4 penetrates the ceiling wall 3 of the melting furnace body 2 and is configured to be able to move up and down the furnace chamber 6 by being supported by the lifting device 15.

  The main electrode 4 is made of metal or graphite and has a cylindrical shape in which a passage for generating plasma gas is formed. At the lower end of the main electrode 4, a furnace bottom electrode 7 is installed on the furnace bottom wall 5 facing the tip, and a DC power source 8 for plasma generation is connected between these electrodes 4, 7. The DC power source 8 is connected to + on the furnace bottom electrode 7 side and connected to-on the main electrode 4 side. The melting furnace main body 2 is provided with a cooling jacket (not shown) for cooling the refractory bricks on the furnace side wall 11, and the periphery thereof is covered with the iron skin 10. On the lower wall portion of the melting furnace main body 2, a tap hole 18 that is a discharge port for the molten slag 23 is disposed, and a tap bar 19 is connected to the tap hole 18. On the furnace side wall 11 of the ash melting furnace 1, an ash supply device 21 for introducing the incinerated ash supplied from the hopper 20 into the furnace chamber 6 is disposed.

  FIG. 2 shows a granulated slag treatment device 25 according to the present invention, and this treatment device 25 includes a granulation tank 26 and a granulation conveyor 27. The water granulating tank 26 is disposed immediately below the tip of the tap 19 and communicates with the exhaust port 16 of the combustion gas provided above the tip of the tap 19. Cooling water 28 is stored in the granulating tank 26, and a horizontal portion 27 a located on the lower end side of the granulating conveyor 27 is disposed along a horizontal plane 26 a that is a bottom portion on one end side of the granulating tank 26. Yes. In addition, an inclined surface 26b is formed on the other end side of the granulating tank 26, and an inclined portion 27b located on the upper end side of the granulating conveyor 27 is disposed along the inclined surface 26a. The granulating conveyor 27 includes a driving wheel 27c on the inclined portion 27b side, a driven wheel 27d on the horizontal portion 27a side, and an endless belt 27e is wound around these peripheral portions. A large number of scraping claws 27f are attached to the outer periphery of the endless belt 27e, and the endless belt 27e can rotate in the direction of arrow a by the driving force of the driving wheel 27c.

  A granulated slag discharge port 29 is formed at the upper part of the inclined surface 26 b of the granulating tank 26 and at the upper and lower surface of the granulating conveyor 27. The wall 30 facing the falling part of the granulated slag at the discharge port 29 is provided with a cleaning spray 31, and the spray angle of the cleaning spray 31 is controlled by the control unit 36 so that the spray angle can be adjusted up and down. Between the inclined surface 26b and the lower surface of the granulating conveyor 27, it is arrange | positioned so that washing water can be sprayed. An opening / closing valve 32 is connected to the cleaning spray 31 via a pipe line, and the opening / closing valve 32 is connected to a supply source 33 of distilled water or tap water. The water crushing tank 26 is provided with a detector 35 that detects the amount of water stored in the cooling water 28. The detector 35 is connected to a control unit 36, and the control unit 36 can adjust the opening degree of the opening / closing valve 32. It is configured as follows. The ash melting furnace 1 is provided with a number of control devices (not shown) for controlling plasma and the like, a gas supply facility for generating plasma, and other devices. Similarly, the pulverized slag treatment device 25 has other devices. However, detailed description thereof will be omitted.

  Next, the operation of the embodiment of the present invention will be described. As shown in FIG. 1, incinerated ash is sequentially put on the furnace bottom wall 5 from the hopper 20 through the ash supply device 21 into the furnace chamber 6 of the ash melting furnace 1. In the furnace chamber 6 of the ash melting furnace 1, a voltage is applied between the plasma electrodes 4 and 7 by the DC power supply 8 with the inside of the furnace chamber 6 in a reducing atmosphere. Then, a plasma arc is generated between the electrodes 4 and 7, the atmosphere in the furnace chamber 6 becomes 1000 ° C. or higher, and melting of the incineration ash is started.

In the incineration ash melting operation, the incineration ash is heated and melted by the heat of the plasma arc to form the molten slag 23. Similarly, the metal component contained in the incineration ash is melted to form the molten metal 24, and the slag having a low specific gravity is obtained. 23 floats to the upper part, and the metal 24 having a higher specific gravity sinks to the lower part of the slag 23. When the slag 23 accumulates in the furnace bottom and reaches the height of the tap 18, the slag 23 overflows from the tap 18, passes through the tap 19, and flows down to the cooling water 28 of the granulating tank 26. Hot molten slag 23, by being rapidly cooled by the cooling water 28, the granulated slag 34 is a particle-like mass. Granulated slag 23, by being placed between the scraping claws 27f of granulated conveyor 27, from the horizontal plane 26a of the water砕槽26 are transported on the inclined surface 26b by the rotation of the endless belt 27e, discharged from the discharge port 29 Is done. The granulated slag 34 is washed at the discharge port 29 with atomized distilled water ejected by the washing spray 31. At this time, even if the cooling water 28 in the granulating tank 26 is contaminated with the above-described dissolved salt, unmelted incinerated ash, combustion gas, etc. in the column of the prior art and adheres to the surface of the granulated slag 34, distillation is performed. Can be washed with water.

  When the molten slag 23 is solidified as the granulated slag 34, 60 g of cooling water per kg evaporates with respect to the slag 23, and the amount of evaporation (if it is drained for other reasons, the decrease is also However, in this embodiment, when the water of the cleaning spray 31 is sprayed onto the granulated slag 34, the inclined surface 26b and the granulated conveyor are required. Since the water is sprayed between the cooling water and the water 27, the cooling water can be replenished by entering the granulating tank 26. Since the detector 35 can detect the amount of water stored or the liquid level in the granulation tank 26, the controller 36 can adjust the opening of the open / close valve 32 in order to adjust the amount of cooling water. Alternatively, when the spray amount of the cleaning spray 31 is larger than the evaporation amount of the cooling water 28, the cleaning water does not enter the granulating tank 26 with the inclination angle of the cleaning spray 31 slightly downward according to a command from the control unit 36. It can also be. Conventionally, the water supply port 67 for replenishing the evaporation of the cooling water has been provided, but in the present embodiment, it can be omitted or the water supply port 67 can be supplemented.

The embodiment of the present invention has been described above. Of course, the present invention is not limited to this, and various modifications can be made based on the technical idea of the present invention. For example, in the above embodiment, the supply distilled water or tap water from the washing spray so as to correspond to the decrease amount of the cooling water in the water砕槽, not supply the entire decrease amount, a portion of the decrease amount You may make it replenish.

It is a schematic sectional drawing of the plasma arc type ash melting furnace in embodiment of this invention. It is a schematic sectional drawing of the processing apparatus of the granulated slag arrange | positioned under the ash melting furnace in the same embodiment. It is a schematic sectional drawing of the processing apparatus of the granulated slag arrange | positioned in the lower part of the conventional ash melting furnace. It is an expanded sectional view of the tap opening part of the ash melting furnace of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Plasma arc type ash melting furnace 2 Melting furnace main body 3 Ceiling wall 4 Main electrode 5 Furnace bottom wall 6 Furnace room 7 Furnace bottom electrode 8 DC power supply 10 Iron skin 11 Furnace side wall 15 Lifting device 16 Exhaust port 18 Outlet 19 Outlet樋 20 Hopper 21 Ash supply device 23 Molten slag 24 Molten metal 25 Granulated slag processing device 26 Granulating tank 26a Horizontal surface 26b Inclined surface 27 Granulating conveyor 28 Cooling water 29 Discharge port 30 Wall 31 Cleaning spray 32 Opening and closing valve 33 Distillation Water supply source 34 Granulated slag 35 Detector 36 Control unit

Claims (1)

The molten slag discharged from the tap outlet of the plasma arc ash melting furnace is granulated with cooling water in the granulation tank to produce granulated slag, and the granulated slag is transferred to the above by a conveyor. In the processing apparatus for the granulated slag discharged outside the granulating tank, the conveyor includes a plurality of scraping claws that move along the inclined surface from the bottom of the granulating tank, and the water settled on the bottom of the granulating tank transportable der Rutotomoni the granulated slag to a discharge portion positioned at the upper portion of the inclined surface, the cleaning spray for injecting wash water between the upper and the conveyor of the inclined surface of the water砕槽in said discharge portion An apparatus for treating granulated slag, comprising the granulated slag between the scratching claws , wherein the granulated slag can be washed, and the washing water flows into the granulation tank.

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