JP2003329225A - Melting furnace apparatus, its operating method and gasifying melting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a melting furnace apparatus, its operating method and gasifying melting system, for which a large quantity of slag cooling water for replacement of the slag cooling water to prevent corrosion at liquid contact part of the slag cooling water of a water-granulated slag producing mechanism due to acidification of the slag cooling water or a large quantity of caustic soda for adjusting pH is not required, at a low running and initial cost. <P>SOLUTION: The melting furnace apparatus having a melting furnace 10 obtaining molten slag 18 by melting ash and the water-granulated slag producing mechanism 30 producing water-granulated slag 18' by contacting the molten slag 18 discharged from the melting furnace 10 with the slag cooling water is provided with a flocculated and settled water supplying mechanism 40 supplying flocculated and settled water 46 by means of iron salt for supplying the flocculated and settled water 46 as a whole or part of the slag cooling water to the water-granulated slag producing mechanism. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a melting furnace apparatus for producing water granulated slag by contacting molten slag discharged from a melting furnace which melts ash into molten slag with slag cooling water, and a method of operating the melting furnace apparatus. And a gasification melting system.

[0002]

2. Description of the Related Art It is desired to incinerate and reduce the amount of municipal solid waste, industrial waste, medical waste, shredder dust, old tires, and the like, and to effectively utilize the incineration heat. Since the incineration ash of waste usually contains harmful heavy metals, in order to treat the incineration ash by landfill,
It is necessary to take measures to solidify the heavy metal components. Furthermore, downscaling of the entire facility is also required. As equipment that can cope with such a problem, while recovering various metals, ash is formed by melting ash, the slag can be recovered, and energy such as heat and electric power can be recovered, In recent years, a gasification and melting furnace that enables material recycling, not just incineration, has been receiving attention.

This gasification and melting furnace gasifies the waste in the gasification furnace and contains unburned carbon and ash at a temperature of 500 ° C.
After producing unburned gas of about 600 ° C, the produced gas (including unburned carbon content and ash) is introduced into the melting furnace and secondary air introduced in the melting furnace produces a low air ratio (1.3- 1.
5) to burn at a high temperature to a temperature above the melting point of ash (1300 ° C or higher, preferably about 1350 ° C). In this high temperature state, the ash is collected on the wall surface of the furnace to generate a molten slag flow.
This molten slag is put into a granulated slag generation mechanism and brought into contact with slag cooling water to generate and collect granulated slag.

FIG. 1 is a diagram showing a configuration example of a conventional melting furnace and a melting furnace apparatus having a granulated slag generating mechanism. In the figure, 10 is a melting furnace and 30 is a granulated slag generation mechanism. The melting furnace 10 includes a primary combustion chamber 11 and a secondary combustion chamber 1
The secondary combustion chamber 13 is provided. Unburned gas containing unburned carbon and ash gasified in a gasification furnace (not shown) 14
Is introduced into the upper part of the primary combustion chamber 11 of the melting furnace 10 in the tangential direction of the furnace wall, and the combustion air 1 introduced into the primary combustion chamber 11 is introduced.
5 is mixed with 5 and burns at a high temperature (temperature of 1350 ° C.) to the secondary combustion chamber 12 and moves to the combustion gas 16 and is further mixed with the combustion air 15 in the tertiary combustion chamber 13 and burned to generate the exhaust gas 1
6'is discharged to a waste heat boiler or the like (not shown). In addition, in FIG. 1, reference numerals 21 and 22 are temperature rising / assisting combustion burners.

As described above, the unburned gas 14 containing unburned carbon and ash introduced into the upper portion of the primary combustion chamber 11 forms a swirling flow and moves to the secondary combustion chamber 12 while burning. Due to the centrifugal force of this swirling flow, the ash is collected on the furnace wall and melted at a high temperature to become the molten slag 18, which falls from the molten slag discharge part 17 into the granulated trough 31 of the granulated slag generation mechanism 30. The granulated trough 31 is supplied with the slag cooling water 19,
The slag cooling water 19 flows through the bottom of the granulation trough 31. The molten slag 18 that has fallen is the slag cooling water 19
And falls into a granulated slag 18 ′ and is transferred to the slag separation conveyor 32. The granulated slag 18 ′ is scraped out by the scraper 33 on the slag separating conveyor 32 and discharged from the granulated slag discharge port 34.

The slag cooling water 19 in the slag separation conveyor 32 is supplied to the water granulation trough 31 by the pump 35, flows from the water granulation trough 31 into the slag separation conveyor 32, and is circulated. The molten slag 18 discharged from the molten slag discharge part 17 of the melting furnace 10 comes into contact with the slag cooling water 19 to become granulated slag 18 ′. At this time, the slag discharge part 17 and the granulated trough 31 are separated from each other. Therefore, the combustion gas 16 having a low temperature exists inside the water granulation trough 31, and the hydrogen chloride content in the combustion gas 16 moves to the slag cooling water side to acidify the slag cooling water 19. When the slag cooling water 19 is acidified, the dissolved chlorine content produces dilute hydrochloric acid, which causes corrosion of the slag separation conveyor 32 and the like. Therefore, in order to prevent corrosion, the slag cooling water 19 is replaced or a part thereof is withdrawn to maintain the water quality, or the pH is adjusted using caustic soda. Therefore, a large amount of slag cooling water 19 is used, a large amount of caustic soda is required for pH adjustment, the running cost increases, and the cost becomes high because the conveyor or the like is made of a material having corrosion resistance. was there.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and in order to prevent corrosion of the slag cooling water contact portion of the granulated slag generation mechanism due to acidification of the slag cooling water, the slag is used. No need for large amount of slag cooling water by exchanging or withdrawing cooling water, and no need for large amount of caustic soda for pH adjustment, low running cost and initial cost, and quality of water granulated slag It is an object of the present invention to provide a melting furnace device, an operating method thereof, and a gasification melting system that do not reduce the temperature.

[0008]

In order to solve the above-mentioned problems, the invention according to claim 1 relates to a melting furnace for melting ash into molten slag, and a molten slag discharged from the melting furnace for cooling slag. In a melting furnace device equipped with a water granulation slag generation mechanism that is contacted with a water granulation slag, a coagulation sedimentation treated water supply mechanism for supplying coagulation sedimentation treated water with iron salt is provided,
The coagulation-sedimentation-treated water is supplied from the coagulation-sedimentation-treated water supply mechanism to the granulated slag generation mechanism as all or part of the slag cooling water.

By providing the coagulation-sedimentation-treated water supply mechanism as described above and supplying the coagulation-sedimentation-treated water as all or part of the slag cooling water, the coagulation-sedimentation-treated water by the iron salt (ferric chloride, etc.) pH is alkaline (eg pH 9-1)
Since it is 1), the pH changes in the direction of being neutralized by coming into contact with the molten slag. Therefore, by controlling the flow rate of the coagulation-sedimentation-treated water so that the slag cooling water does not become acidic, it is possible to prevent corrosion of the slag cooling water contact portion of the granulated slag generation mechanism. Therefore, unlike the conventional case, caustic soda is not required for exchanging / withdrawing slag cooling water and adjusting pH, or it is possible to reduce the amounts of slag cooling water and caustic soda used.

According to the second aspect of the present invention, a melting furnace that melts ash to form molten slag, and a granulated slag that produces water granulated slag by contacting the molten slag discharged from the melting furnace with slag cooling water. In a method for operating a melting furnace device having a production mechanism, the coagulation sedimentation treatment water with iron salt is supplied as all or part of the slag cooling water of the granulated slag production mechanism.

As described above, by supplying the coagulation-sedimentation-treated water with the iron salt as all or a part of the slag cooling water of the water granulated slag generating mechanism, the slag cooling water contact portion of the water granulated slag generating mechanism is the same as above. Therefore, it is possible to prevent the use of caustic soda for exchanging / withdrawing slag cooling water and adjusting pH as in the conventional case, or to reduce the amount of slag cooling water and caustic soda used.

The invention according to claim 3 is a gasification apparatus comprising a gasification furnace for gasifying waste, and melting of ash in the gas discharged from the gasification furnace to form molten slag. In a gasification melting system equipped with a furnace and a granulated slag generating mechanism for contacting molten slag discharged from the melting furnace with slag cooling water to generate granulated slag, coagulation precipitation for supplying treated water with coagulation precipitation with iron salt A feature is that a treated water supply mechanism is provided, and the aggregated and precipitated treated water is supplied from the agglomerated and precipitated treated water supply mechanism to the granulated slag generation mechanism as all or part of the slag cooling water.

By providing the coagulation-sedimentation-treated water supply mechanism as described above and supplying the coagulation-sedimentation-treated water as all or part of the slag cooling water, the slag cooling water contact part of the granulated slag producing mechanism is the same as above. Therefore, it is possible to prevent the use of caustic soda for exchanging / withdrawing slag cooling water and adjusting pH as in the conventional case, or it is possible to reduce the amounts of slag cooling water and caustic soda used. In particular, when the coagulation-sedimentation treated water generated by the gasification and melting system is used, the running cost and initial cost for producing the granulated slag can be significantly reduced.

The invention according to claim 4 is a gasification apparatus comprising a gasification furnace for gasifying waste, and melting of ash in the gas discharged from the gasification furnace to form molten slag. Furnace, a water granulation slag generation mechanism for contacting molten slag discharged from the melting furnace with slag cooling water to generate water granulated slag, and for treating exhaust gas discharged from the melting furnace installed in the latter stage of the melting furnace A gasification and melting system including a cleaning tower is characterized in that water supply means for supplying all or part of the slag cooling water of the granulated slag generation mechanism to the cleaning tower as supplementary water is provided.

When all or part of the slag cooling water of the water granulated slag generating mechanism is supplied to the cleaning tower as makeup water by the water supply means as described above, if the wastewater treatment capacity of the entire equipment is made constant, the cleaning tower As the amount of slag cooling water withdrawn corresponding to the amount of makeup water can be increased, the concentration of corrosive substances in the slag cooling water can be controlled, and the wetted slag generation mechanism's wetted parts can be controlled, as described in detail later. Prevent corrosion of parts,
Longer service life (life). Further, it is possible to prevent deterioration of the quality of the granulated slag produced. In addition, the environmental load can be reduced by reusing the slag cooling water as makeup water for the washing tower. Further, since the amount of slag cooling water supplied can be increased with respect to the amount of water equivalent to the amount of makeup water supplied to the cleaning tower, it is possible to suppress the temperature rise of the slag cooling water by adding new water separately.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is a diagram showing an example of the configuration of a melting furnace apparatus including a melting furnace and a granulated slag generation mechanism according to the present invention. The melting furnace apparatus includes a melting furnace 10 and a water granulated slag generation mechanism 30, and the melting furnace 10 includes a primary combustion chamber 11,
It has a secondary combustion chamber 12 and a tertiary combustion chamber 13, and an unburned gas 14 containing unburned carbon and ash is introduced into the upper part of the primary combustion chamber 11 and combustion air 15 introduced into the primary combustion chamber 11 While mixing and burning at a high temperature (temperature of about 1350 ° C.), the combustion gas 16 moves to the secondary combustion chamber 12, and the tertiary combustion chamber 1 further moves.
3 is similar to the conventional example shown in FIG. 1 in that it is mixed with the combustion air 15 and burned to form an exhaust gas 16 'which is discharged to a waste heat boiler or the like (not shown).

In addition, unburned gas containing unburned carbon and ash 14
As a result of the swirling flow, ash is collected on the furnace wall and melted at a high temperature to form molten slag 18, which falls from the molten slag discharge part 17 into the granulated trough 31 of the granulated slag generation mechanism 30 and the slag inside the granulated trough 31. Contact with cooling water 19 and granulated slag 1
8'is transferred to the slag separation conveyor 32, scraped out by the scraper 33 on the slag separation conveyor 32, and discharged from the water granulated slag discharge port 34, similarly to the conventional example shown in FIG.

Reference numeral 40 denotes a coagulation-sedimentation-treated water supply mechanism for supplying coagulation-sedimentation-treated water 46 to the granulated slag generation mechanism 30 as the whole or a part of the slag cooling water 19, and the coagulation-sedimentation-treated water supply mechanism 40 causes the coagulation-sedimentation treatment. The water supply line 41 is provided with a flow rate control valve 42. The flow rate control valve 42 is controlled by the control of the control unit 43, and the coagulation sedimentation treated water 46
Is supplied to the slag separation conveyor 32 of the granulated slag generation mechanism 30 as all or part of the slag cooling water 19. Further, the control unit 43 includes a water level sensor 44 for detecting the water level of the slag cooling water 19, and a pH for detecting the pH value.
The output of the sensor 45 is input.

The coagulation-precipitation treated water 46 is used for coagulating and precipitating lead and mercury by using an iron salt (ferric chloride) as a coagulant, and has an alkaline pH. By using the coagulation / sedimentation treated water 46 as the slag cooling water 19, the molten slag 18 discharged from the molten slag discharge part 17 comes into contact with the alkaline slag cooling water 19 flowing at the bottom of the granulation trough 31. Granulated trough 3 at this time
Since the combustion gas 16 having a low temperature exists inside 1, the hydrogen chloride content in the gas shifts to the slag cooling water side, and the pH value is changed to neutralize and acidify the slag cooling water 19. The pH sensor 45 detects the pH value of the slag-treated water 19 and outputs the detected value to the control unit 43.

When the pH value of the slag-treated water 19 becomes "7" (neutral) or less, the controller 43 replenishes the slag-treated water 19 with a predetermined flow rate of the coagulation-sedimented water 46 through the flow control valve 42. Increase the pH value of (make it alkaline). Thereby, the pH value of the slag-treated water 19 can be maintained in a desired range. Since the water level detection output of the water level sensor 44 is also input to the control unit 43, when the water level of the slag cooling water 19 becomes equal to or lower than a predetermined water level, a coagulation sedimentation process of a predetermined flow rate is performed via the flow rate control valve 42. Water 46 is replenished, or a predetermined flow rate of slag cooling water is replenished via a slag cooling water supply mechanism (not shown). In addition, surplus water generated by the supply of treated water or makeup water is sent to wastewater treatment.

In the above example, the granulated slag generation mechanism 30 is used.
Is provided with a granulated trough 31, and the molten slag 18 discharged from the molten slag discharge part 17 and the slag cooling water 19 are brought into contact with each other in the granulated trough 31 to generate a granulated slag 18 '. For example, as shown in FIG. 3, the molten slag 18 discharged from the molten slag discharge unit 17 is directly charged into the slag separation conveyor 32, and the generated water granulated slag 18 ′ is scraped by the scraper 33. It may be scraped out and discharged from the granulated slag discharge port 34. In short, the molten slag discharged from the melting furnace is contacted with the slag cooling water of the water granulated slag generation mechanism to generate water granulated slag, and iron salt as a coagulant is added to all or part of the slag cooling water. Any structure may be used as long as the coagulation-precipitated water to be used is used.

In the melting furnace apparatus of FIG. 3, the secondary combustion chamber 1
Since there is no partition between the slag discharge part 17 and the slag discharge part 17, there is no partition between the slag discharge part 17 and the slag discharge part 17.
Is full. Therefore, the pollutants contained in the combustion gas 16 are directly absorbed (dissolved or suspended) in the slag cooling water, and the slag cooling water 19 is contaminated and acidified (pH value becomes excessively low). Bring about a phenomenon.

This phenomenon not only deteriorates the quality of the water granulated slag 18 ', but also causes corrosion of the material of the piping system of the slag separating conveyor 32 and the pump 35. In order to avoid this problem, it is important to prevent deterioration of the water quality of the slag cooling water 19 or to alleviate the deterioration of the water quality of the slag cooling water 19 as much as possible. Therefore, from this point of view, a more preferable embodiment example capable of maintaining the water quality of the slag cooling water 19 will be described here.

FIG. 4 is a diagram showing an example in which part or all of the slag cooling water 19 is used as makeup water for the wet exhaust gas treatment in the latter stage of the melting furnace. As shown in the figure, the exhaust gas 16 ′ generated in the melting furnace 10 is a boiler 51, an economizer 52,
Cooling tower 53, bag filter 54, IDF 55, cleaning tower 5
6. It is discharged from the chimney 59 into the atmosphere through the reheater 57 and the catalyst tower 58. In the cleaning tower 56, which is a wet exhaust gas treatment device, high-temperature exhaust gas is cleaned by water spraying, and therefore it is necessary to constantly replenish the decrease in cleaning water due to evaporation. If a part or all of the slag cooling water 19 is used as the makeup water 60 used in the washing tower 56, the makeup water 60
Is greater than the amount of slag cooling water 19 extracted, it is possible to increase the amount of slag cooling water 19 extracted.

Conventionally, the polluted and acidified slag cooling water 19 of the granulated slag generating mechanism 30 was separately sent to a wastewater treatment facility, but here, part or all of the slag cooling water 19 is continuously treated. By supplying the cleaning tower 56 either intermittently or intermittently, it is possible to greatly increase the amount of slag cooling water withdrawn, which was conventionally limited by the capacity of the wastewater treatment facility. That is, since the makeup water 60 of the cleaning tower 56 is used as the slag cooling water 19 and then supplied to the cleaning tower 56, the amount of the slag cooling water 19 extracted can be increased to a considerable amount of the makeup water 60. As a result, it becomes possible to increase the amount of makeup water of the slag cooling water 19 without restrictions on the wastewater treatment capacity and without increasing the amount of water used. As a result, the slag cooling water 19
Is diluted, and it becomes possible to reduce the concentration of pollutants contained therein or maintain the pH at a constant value. By using the slag cooling water 19 for makeup water in the washing tower 56 in this manner, the amount of makeup water of the slag cooling water 19 can be increased and the quality of the water can be maintained. The blow water 61 from the washing tower 56 is sent to the wastewater treatment facility 62. This method has the following advantages.

Since the concentration of corrosive substances (corrosion source substances) in the slag cooling water 19 can be controlled, it is possible to prevent corrosion of the separation conveyor 32 and increase the service life (years).

By improving the quality of the slag cooling water that adheres to the surface of the granulated slag 18 ', it is possible to prevent the quality of the slag from deteriorating (prevention of heavy metal elution).

Further, from the viewpoint of reducing the environmental load so that the waste is not emitted from the treatment facility as much as possible, it is advantageous to reuse the slag cooling water 19.

Conventionally, water was newly brought from outside as makeup water for the washing tower 56, but the amount of water used from outside can be reduced by the amount filled with the slag cooling water 19.

By reusing the water extracted from the slag cooling water 19, the load on the wastewater treatment facility can be reduced.

Since the slag cooling water 19 comes into contact with the high temperature molten slag 18, it is important to always cool it.
Here, since the amount of makeup water for the slag cooling water 19 can be increased, new water can be added separately,
The temperature rise of the slag cooling water 19 can be suppressed.

Although not shown, the gasification and melting system according to the present invention includes a gasification apparatus having a gasification furnace for gasifying waste, a melting furnace and a water granulator having the configuration shown in FIG. 2 or 3. The gasification furnace of the gasification apparatus may be a fluidized bed gasification furnace, a kiln furnace, an external circulation type fluidized bed gasification furnace, or the like. Further, the gasification furnace may be of a type in which unburned carbon and gas are once separated and then separately introduced into a melting furnace.

In the gasification and melting system, in order to remove lead and mercury in the waste liquid, an iron salt (ferric chloride etc.) is used as a coagulant.
In many cases, there is coagulation-sedimentation-treated water obtained by coagulation-sedimentation treatment of lead or mercury using a treatment liquid containing. By using this coagulation-sedimentation-treated water together with slag cooling water, it is possible to generate granulated slag at extremely low running cost and initial cost while preventing corrosion of the slag cooling water contact part of the granulated slag generation mechanism.

In any of the above-mentioned embodiments, it goes without saying that a small amount of pH adjusting agent (caustic soda, etc.) can be used.

[0035]

As described above, according to the invention described in each claim, the following excellent effects can be obtained.

According to the first aspect of the present invention, a coagulation-sedimentation-treated water supply mechanism is provided, and the coagulation-sedimentation-treated water is supplied as all or a part of the slag cooling water, whereby an iron salt (ferric chloride, etc.) is supplied. Since the pH of the coagulation-precipitation treated water according to (4) is alkaline, the pH changes toward neutralization by contact with combustion gas. Therefore, by controlling the flow rate of the coagulation-sedimentation-treated water so that the slag cooling water does not become acidic, it is possible to prevent corrosion of the slag cooling water contact portion of the granulated slag generation mechanism. Therefore, unlike the conventional case, caustic soda is not required for exchanging slag cooling water or adjusting pH, or the amounts of slag cooling water and caustic soda used can be reduced.

According to the second aspect of the present invention, by supplying coagulation-sedimentation-treated water with an iron salt as all or part of the slag cooling water of the granulated slag generating mechanism, the granulated slag generating mechanism is the same as above. Corrosion of the slag cooling water contact part can be prevented, and therefore caustic soda is not required for replacing / withdrawing slag cooling water and adjusting pH as in the past, or reducing the amount of slag cooling water and caustic soda used. You can

According to the third aspect of the present invention, a coagulation-sedimentation-treated water supply mechanism is provided, and the coagulation-sedimentation-treated water is supplied as all or a part of the slag cooling water, so that the same granulated slag generation mechanism as described above is provided. Corrosion of the slag cooling water contact part can be prevented, and therefore caustic soda is not required for replacing / withdrawing slag cooling water and adjusting pH as in the past, or reducing the amount of slag cooling water and caustic soda used. You can In particular, when the coagulation-sedimentation treated water generated by the gasification and melting system is used, the running cost and initial cost for producing the granulated slag can be significantly reduced.

According to the fourth aspect of the present invention, by supplying all or part of the slag cooling water of the granulated slag generation mechanism to the cleaning tower as makeup water by the water supply means, the amount of makeup water in the cleaning tower is increased. Since the amount of slag cooling water supplied (the amount of extracted water) can be increased, the concentration of corrosive substances in the slag cooling water can be reduced, the corrosion of the wetted part of the granulated slag generation mechanism can be prevented, and the service life ( Longer life). Further, it is possible to prevent the quality of the generated water granulated slag from being deteriorated, and by reusing the slag cooling water as makeup water for the washing tower, it is possible to reduce the load on the wastewater treatment facility. Further, since the amount of slag cooling water supplied can be increased, it is possible to suppress the temperature rise of the slag cooling water by adding new water separately.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration example of a conventional melting furnace device.

FIG. 2 is a diagram showing a configuration example of a melting furnace device according to the present invention.

FIG. 3 is a diagram showing another configuration example of the melting furnace apparatus according to the present invention.

FIG. 4 is a diagram showing a configuration example of a system that uses slag cooling water of the melting furnace apparatus according to the present invention as makeup water.

[Explanation of symbols]

10 melting furnace 11 Primary combustion chamber 12 Secondary combustion chamber 13 tertiary combustion chamber 14 unburned gas 15 Combustion air 16 Combustion gas 16 'exhaust gas 17 Molten slag discharge part 18 Molten slag 18 'granulated slag 19 Slag cooling water 21 Temperature rising / burning burner 22 Temperature rising / burning burner 30 Granulated slag generation mechanism 31 granulated trough 32 slag separation conveyor 33 scraper 34 Granulated slag discharge port 35 pumps 40 Aggregation and sedimentation treatment water supply mechanism 41 Coagulation sedimentation treated water supply line 42 Flow control valve 43 Control unit 44 Water level sensor 45 pH sensor 46 Coagulation sedimentation treated water 51 Boiler 52 Economizer 53 Cooling tower 54 Bug Filter 55 IDF 56 Washing tower 57 Reheater 58 catalyst tower 59 chimney 60 makeup water

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C02F 1/52 B09B 3/00 303L F23G 5/027 ZAB B01D 53/34 134B 5/44 (72) Inventor Kaneko Mitsuyoshi 11-11 Haneda-Asahi-cho, Ota-ku, Tokyo (72) Inventor Masaaki Irie 11-11 Haneda-Asahi-cho, Ota-ku, Tokyo E-term Co., Ltd. F-term (reference) 3K061 AA23 AB02 AB03 AC03 BA03 CA01 DA13 DB12 DB16 FA25 3K065 AA23 AB02 AB03 AC03 BA03 4D002 AA19 AB01 AC04 BA02 BA13 BA14 DA35 DA70 4D004 AA11 AA28 AA36 AA46 AA48 AB03 AB06 BA05 CA27 CA29 CA32 CA35 CB34 CB45 4D015 CA13 CA20 DA15 BA19 BA22 DA22 BB05

Claims (4)

[Claims] 1. A melting furnace comprising a melting furnace for melting ash to form molten slag, and a granulated slag generation mechanism for contacting the molten slag discharged from the melting furnace with slag cooling water to generate granulated slag. In the apparatus, a coagulation-sedimentation-treated water supply mechanism for supplying coagulation-sedimentation-treated water with an iron salt is provided, and the coagulation-sedimentation-treated water is supplied from the coagulation-sedimentation-treated water supply mechanism to the granulated slag generation mechanism as all or part of slag cooling water. And a melting furnace device. 2. A melting furnace comprising a melting furnace for melting ash to form molten slag, and a water granulation slag generation mechanism for contacting the molten slag discharged from the melting furnace with slag cooling water to generate water granulated slag. A method of operating a melting furnace apparatus, comprising supplying coagulation / sedimentation treated water with iron salt as all or part of the slag cooling water of the granulated slag generation mechanism. 3. A gasification apparatus having a gasification furnace for gasifying waste, a melting furnace for melting ash in the gas discharged from the gasification furnace to form molten slag, and a discharge for the melting furnace. In a gasification and melting system equipped with a water granulation slag generation mechanism for generating water granulation slag by bringing molten slag into contact with slag cooling water, a coagulation sedimentation treatment water supply mechanism for supplying coagulation sedimentation treatment water with iron salt is provided, A melting furnace apparatus characterized in that coagulation-sedimentation-treated water is supplied from the coagulation-sedimentation-treated water supply mechanism to the granulated slag generation mechanism as all or part of slag cooling water. 4. A gasifier equipped with a gasification furnace for gasifying waste, a melting furnace for melting ash in the gas discharged from the gasification furnace to form molten slag, and discharge from the melting furnace. A gas comprising a water granulation slag generation mechanism for contacting molten slag with slag cooling water to generate water granulation slag, and a washing tower installed at a subsequent stage of the melting furnace for treating exhaust gas discharged from the melting furnace A gasification and melting system in which a water supply means for supplying all or part of the slag cooling water of the granulated slag generation mechanism to the cleaning tower as makeup water for the cleaning tower is provided.