JPH11230519A - Waste direct melting furnace and operation method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a waste direct melting furnace which keeps a combustion support gas supply port from being partially closed by a molten slag solidified. SOLUTION: Burners 12... are provided to simultaneously blow out a combustion support gas and a fuel separately to a plurality of combustion support as ports 10... formed at a moving bed furnace 1. The burners 12 is each provided with a fuel supply device unit 20 to supply the fuel to the burner 12 and a combustion support gas supply device unit 33 to supply to supply the combustion support gas to the burner 12. The combustion support gas supply devices 33 and the fuel supply device 22 supply the combustion support gas and the fuel the burners so that a flame is blown out of the burners 12 to block the combustion support gas supply ports 10 from being partially or wholly closed by a molten slag dropping down from a combustion melting zone 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waste melting furnace for treating waste by drying, pyrolysis, burning and melting, and a method for operating a waste melting furnace.

[0002]

2. Description of the Related Art Waste and other wastes are directly melted without burning, and then converted into molten slag and flammable decomposition gas to process the wastes. Melting furnaces were developed in the United States more than 30 years ago, and with respect to this technology and direct waste melting furnaces, see US Pat. No. 3,511,194;
JP-B-51-42434, JP-B-52-24790, JP-B-57-10348, JP-B-61-4
No. 9565 and the like.

[0003] In this direct waste melting furnace, a moving bed type furnace includes a drying region where the waste is dried, a pyrolysis region where the dried waste is thermally decomposed, and a combustion melting region where the pyrolyzed waste is burned and melted. Are formed in order from the upper side to the lower side inside. Further, from the furnace bottom side of the moving bed type furnace, a combustion supporting gas composed of an oxygen-enriched gas or preheated air is supplied to the combustion melting region. As disclosed in Japanese Patent Publication No. 52-24790 and the like, a plurality of combustion supporting gas supply ports for supplying a combustion supporting gas into the moving bed type furnace are provided with waste formed in the moving bed type furnace. A portion of the peripheral wall portion located below the combustion and melting region that burns and melts is provided at a predetermined interval in the circumferential direction. The combustion supporting gas contains oxygen less than the theoretical amount of oxygen necessary for complete combustion of the waste. And the molten slag that fell from the combustion melting area,
The combustible cracked gas that is temporarily stored at the bottom of the furnace and then discharged (generally continuously discharged) and stored in the space formed above the drying area of the moving bed type furnace is discharged outside the furnace.

[0004]

However, in the conventional waste direct melting furnace, the molten slag flowing down from the combustion melting zone is cooled and solidified by the combustion supporting gas blown from the combustion supporting gas supply port, and the combustion supporting gas supply port. There was a problem of partially or totally plugging. If the combustion support gas supply port is partially blocked, the supply amount of the combustion support gas, that is, the amount of gas ejected changes, so that the amount of gas flowing in the moving bed furnace greatly fluctuates, and the melting treatment of waste is not possible. The problem of becoming stable occurs.

It is an object of the present invention to provide a waste direct melting furnace and a method of operating a waste direct melting furnace in which a combustion supporting gas supply port is not partially blocked by solidified molten slag. .

Another object of the present invention is to provide a waste direct melting furnace and a method of operating a waste direct melting furnace which can stably perform a melting treatment of a waste even if the load fluctuates. .

Still another object of the present invention is to provide a waste direct melting furnace and a method of operating a waste direct melting furnace which do not cause large fluctuations in the furnace temperature and the furnace pressure even when the load fluctuates. To provide.

It is still another object of the present invention to provide a direct waste melting furnace and a method of operating a direct waste melting furnace, which can reduce the operating cost at low load.

It is another object of the present invention to provide a waste direct melting furnace in which the calorific value and supply amount of fuel supplied to a burner provided at a combustion supporting gas supply port can be easily adjusted.

[0010]

SUMMARY OF THE INVENTION In the present invention, a moving bed type furnace is used as a waste direct melting furnace to be improved. This moving bed furnace has a waste inlet in an upper wall portion or an upper portion of the peripheral wall portion, and a peripheral portion of the peripheral wall portion located in a lower portion of the combustion and melting region where the waste is burned and melted. A plurality of combustion supporting gas supply ports are provided at predetermined intervals. The direct waste melting furnace has a waste loading device that feeds waste into the moving bed furnace through a waste loading port, and a combustion supporting gas that flows into the moving bed furnace through multiple combustion supporting gas supply ports. And a combustion supporting gas supply device for supplying.

In the present invention, a plurality of burners for simultaneously blowing out the combustion support gas and the fuel are provided at the plurality of combustion support gas supply ports, respectively, and a fuel supply device for supplying the fuel to these burners is provided. And a combustion support gas supply device and a fuel supply device for blowing out a flame from the plurality of burners for preventing the plurality of combustion support gas supply ports from being partially or wholly blocked by the molten slag flowing down from the combustion melting region. Supply combustion support gas and fuel to a plurality of burners. By providing a plurality of burners for simultaneously blowing out the combustion support gas and the fuel at the combustion support gas supply port, and raising the temperature of the combustion support gas blown from the combustion support gas supply port by the flame of the burner, the combustion from the combustion melting region It is possible to prevent the falling molten slag from solidifying in the vicinity of the combustion supporting gas supply port and partially blocking the combustion supporting gas supply port by the solidified molten slag. As a result, it is possible to suppress a change in the amount of gas supplied from the combustion supporting gas supply port, and to obtain an advantage that the melting treatment of the waste is stabilized.

The combustion supporting gas supply apparatus uses high-concentration oxygen having an oxygen purity or concentration of 90% or more to obtain a combustion supporting gas. However, high-concentration oxygen is expensive, and it is necessary to reduce the usage of high-concentration oxygen as much as possible in order to reduce operating costs. To achieve this, the amount of waste (load) in the direct waste melting furnace must be adjusted in accordance with the fluctuations in the amount of waste that differs depending on the season and season.
And it is preferable to adjust the concentration and the supply amount of the combustion supporting gas according to the load. However, most of the currently operating waste direct melting furnaces hardly control the concentration and supply amount of the combustion supporting gas. In the direct waste melting furnace, in order to perform stable melting treatment of waste,
It is necessary to put the waste into the moving bed furnace from the waste charging device so that the upper surface level of the waste in the moving bed furnace is within a certain level range as much as possible. Therefore, if the supply amount of combustion support gas is not adjusted, if the amount of waste input per unit time fluctuates in the season when the amount of waste decreases, the upper surface level of the waste in the moving bed furnace will fluctuate. In addition to the problem that the melting treatment of waste becomes unstable, the operating cost does not decrease despite the reduction of waste treatment volume because the use of high-concentration oxygen does not decrease The problem also arises.

[0013] In the apparatus of the present invention, the combustion supporting gas supply device is configured so that the oxygen concentration and the combustion supporting gas supply amount can be adjusted, and the fuel supply device adjusts the calorific value of the supplied fuel and the fuel supply amount. It is configured to be possible. By the combustion supporting gas supply device and the fuel supply device, the temperature of the flame blown out from the burner falls within the flame temperature range where the molten slag does not adhere and the furnace wall of the moving bed type furnace is not damaged, and the gas flows through the moving bed type furnace. To ensure that the amount of the gas does not fluctuate significantly (so that the furnace temperature of the moving bed furnace falls within the allowable furnace temperature range).
If the oxygen concentration and the amount of combustion support gas supplied and the calorific value and the fuel supply amount are adjusted, or if the oxygen concentration and the combustion support gas supply amount are adjusted without adjusting the heat value and the fuel supply amount, the load may fluctuate. However, the waste can be stably melted.

In order to adjust the oxygen concentration and the supply amount of the combustion supporting gas, for example, a combustion supporting gas supply device is used to adjust the supply amount of high-concentration oxygen having an oxygen concentration of 90% or more. A high-concentration oxygen supply device, an air supply device for supplying preheated air or compressed air having a lower oxygen concentration than the high-concentration oxygen by adjusting the supply amount, a high-concentration oxygen supply device, and a high-concentration oxygen supplied from the air supply device And a mixer for mixing preheated air or compressed air. The use of preheated air can suppress a decrease in the temperature of the burner flame even when the oxygen concentration is adjusted by mixing the air. In addition, in order to adjust the calorific value of the fuel and the fuel supply amount, for example, a fuel supply device is provided with a high calorific value fuel supply device that supplies a high calorific value fuel by adjusting the supply amount, and a high calorific value fuel supply device. A low calorific value fuel supply device that supplies a low calorific value fuel with a low calorific value and supplies a high calorific value fuel and a low calorific value fuel supplied from the high calorific value fuel supply device and the low calorific value fuel supply device And a mixer for mixing the fuel. In this device, the amount of heat generated and the amount of fuel supplied can be adjusted by changing the amount of mixture of the high calorific value fuel and the low calorific value fuel.

If the combustion supporting gas supply apparatus as described above is used, an appropriate oxygen concentration and a suitable amount of combustion supporting gas (corresponding to a change in the amount of waste input per unit time) according to a change in load (movement). It is possible to select the oxygen concentration and the combustion supporting gas supply amount that can suppress the fluctuation of the upper surface level of the waste in the bed furnace. When the load is low, the melt processing speed of the waste is reduced to suppress the fluctuation of the upper surface level of the waste in the moving bed type furnace, so that the oxygen concentration in the combustion supporting gas is reduced. From the viewpoint of the burner, a decrease in the oxygen concentration means that the air ratio approaches 1, and that the temperature of the flame increases if the calorific value of the fuel is the same. If the temperature of the flame is too high, the wall of the moving bed furnace will be damaged by heat. Therefore, when reducing the oxygen concentration in the combustion supporting gas, the temperature of the flame from the burner is adjusted to a flame temperature range (specifically, 1200 ° C. to 18
(00 ° C). It is conceivable to lower the flame temperature by simply reducing the supply amount when supplying the same fuel with the same calorific value. However, if the amount of gas (combustion exhaust gas + combustion support gas) flowing in the moving bed type furnace changes, Not only does the amount of transfer of the waste to the lower side differ, but the contact and heat exchange between the gas and the waste become insufficient, causing a problem that the melting treatment of the waste becomes unstable. Therefore, it is not appropriate to adjust the flame temperature only by adjusting the fuel supply amount. According to the present invention, the calorific value of the fuel can be adjusted, and the supply amount of the combustion supporting gas and the fuel supply amount can also be adjusted. It is possible to prevent the gas from rising, and to suppress the fluctuation of the gas amount flowing in the moving bed furnace.

A high calorific value fuel supply device for supplying a high calorific value fuel to the fuel supply device by adjusting the supply amount, and a low calorific value fuel having a lower calorific value than the high calorific value fuel are supplied by adjusting the supply amount. A low calorific value fuel supply device that has the function of receiving the high calorific value fuel and the low calorific value fuel from the high calorific value fuel supply device and the low calorific value fuel supply device as a burner and mixing them. The need for a separate mixer is eliminated by using.

Also, a high-concentration oxygen supply apparatus for supplying a high-concentration oxygen having an oxygen concentration of 90% or more by adjusting the supply amount, a preheated air or compressed air having a lower oxygen concentration than the high-concentration oxygen. It is composed of an air supply device that regulates the supply amount of air and supplies high concentration oxygen and preheated air or compressed air from the high concentration oxygen supply device and the air supply device as a burner. With the use of such a mixer, there is no need to provide a separate mixer.

In the method for operating a waste direct melting furnace according to the present invention, a plurality of flames for preventing the plurality of combustion supporting gas supply ports from being partially or wholly blocked by molten slag flowing down from the combustion melting region are provided. The oxygen concentration and the combustion support gas supply amount of the combustion support gas supplied to the plurality of burners from the combustion support gas supply device and the calorific value and the fuel supply amount of the fuel supplied to the plurality of burners from the fuel supply device so as to blow out from the burner. Set.

In order to cope with the fluctuation of the load, the load state of the moving bed furnace is determined from the operation state of the waste input device. Then, depending on the load state of the moving bed furnace determined, the temperature of the flame blown out from the plurality of burners enters a flame temperature range that does not fix the molten slag and damage the furnace wall of the moving bed furnace, Oxygen concentration and supply of combustion support gas, and calorific value and fuel supply so that the amount of gas flowing through the furnace does not fluctuate significantly (so that the furnace temperature of the moving bed furnace falls within the allowable furnace temperature range). Adjust

More specifically, when the supply amount of the waste supplied from the waste input device to the moving bed type furnace becomes 80% or less of the design amount, it is determined that the load is low, and the supply amount of the waste is reduced. When it is larger than 80% of the design amount, it is determined as a steady load. When it is determined that the load is low, the injection energy from the plurality of burners is set to 80% or more of the injection energy from the plurality of burners at the steady load, and the flame temperature is set to a flame temperature range of 1200 ° C to 1800 ° C. It is preferable to adjust the oxygen concentration, the combustion support gas supply amount, the heat generation amount, and the fuel supply amount so as to be able to enter. In this way, even when the load is low, it is possible to prevent the combustion supporting gas supply port from being blocked by the partially or totally solidified molten slag, and there is an advantage that a stable melting process can be performed. .

[0021]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic configuration diagram of an example of an embodiment of a waste direct melting furnace of the present invention. In FIG. 1, reference numeral 1 denotes a moving bed type furnace generally called a shaft furnace. Inside the moving bed type furnace 1, a drying area 2 where waste (generally, garbage) dries, a dried waste In the moving bed furnace 1, a pyrolysis region 3 where pyrolysis is performed and a combustion melting region 4 where the pyrolyzed waste is burned and melted are formed in order from top to bottom. The reason why the drying zone 2, the pyrolysis zone 3 and the combustion melting zone 4 are formed, and the phenomena occurring in each zone are described in Japanese Patent Publication Nos. Sho 51-42434 and Sho 52-24790. It is explained in detail in the literature. Further, a waste supply port 5 for supplying waste into the furnace is formed in an upper portion of the peripheral wall portion 1a of the moving bed type furnace 1, and the waste supply port 6 passes through the waste supply port 5 from the waste input device 6. Waste is supplied into the furnace as appropriate.

On the bottom wall 7 of the moving bed type furnace 1, there is formed a storage section 8 for temporarily storing the molten slag flowing down from the combustion and melting area 4, and the molten slag is supplied to a molten slag outlet (not shown). Through the furnace. The molten slag discharged outside the furnace is cooled by a known method and processed as a molten solid. Regarding solidification technology of molten slag, for example, Japanese Patent Publication No. Sho 51-42434, Japanese Patent Publication No. 52-24790, and Japanese Patent Publication No. 57-10348
And Japanese Patent Publication No. 61-49565.

An annular constriction 9 is formed in a portion of the peripheral wall 1a near the bottom wall 7. The constricted portion 9 is formed with an annular inclined wall 9a that opens upward and an annular inclined wall 9b that opens downward. The upper inclined wall 9a constitutes a shelf, and the lower inclined wall 9a.
b, a plurality of combustion support gas supply ports 10 are formed at predetermined intervals in the circumferential direction. Combustion support gas supply port 1
Although the number of 0 is arbitrary, in this example, eight combustion supporting gas supply ports 10 are formed at equal intervals. In FIG. 1, two combustion supporting gas supply ports 9 are illustrated by way of example. At the center of the constricted portion 9, the combustion melting region 4 is provided.
The molten slag flowing down from the combustion support gas supply port 10 ...
An annular guide member 11 for minimizing inflow to the side is disposed.

In this example, burners 12 for simultaneously blowing out the combustion supporting gas and the fuel are inserted into the combustion supporting gas supply ports 10 and fixed. This burner 12
Has a structure in which the fuel supply pipe and the combustion support gas supply pipe are concentrically arranged with the fuel supply pipe inside, and the fuel and the combustion support gas are mixed at the tip of the burner 12. It has become. A part of the combustion supporting gas is used for combustion in the burners 12. In this example, burner 1
Are arranged so as to blow out the flame toward the molten slag in the storage section 8, and the function of the flame of the burner 12 to prevent the molten slag from adhering to the combustion supporting gas supply ports 10 and solidifying. And a function of preventing the molten slag in the storage section 8 from being solidified.

In this example, one burner 12 has one
The fuel supply unit 22 and the combustion support gas supply unit 33 are individually provided for each unit. The fuel supply device unit 22 is capable of adjusting and supplying a high calorific value fuel such as a high calorific value gas such as LPG and LNG and a high calorific value fuel such as kerosene and heavy oil. An apparatus 13 is provided. The high calorific value fuel supply device 13 of this example includes a fuel tank 14 filled with high calorific value fuel and a flow control valve 15. Further, the fuel supply unit 22 controls the low calorific value fuel supply device 16 to supply a low calorific value fuel having a lower calorific value than the high calorific value fuel such as a pyrolysis gas or a combustion exhaust gas. Have. The low calorific value fuel supply device 16 of this example includes a fuel tank 17 filled with a low calorific value fuel and a flow control valve 18. As the combustion exhaust gas used as the low calorific value fuel, purified exhaust gas discharged from the moving bed furnace 1 can be used. Note that the low calorific value fuel has a calorific value of 1000 kcal / Nm ³ or more that can be self-burned by air. High calorific value fuel supply device 1
The high calorific value fuel output from 3 and the low calorific value fuel output from the low calorific value fuel supply device 16 are mixed by a mixer 19. Even if the mixer 19 is provided, it is a matter of course that only the high calorific value fuel or the low calorific value fuel may be supplied to the burner 12 through the mixer 19. 20 and 30 are flow meters, respectively.

The combustion supporting gas supply device unit 33 includes a high-concentration oxygen supply device 23 for supplying a high-concentration oxygen having an oxygen concentration of 90% or more by adjusting the supply amount, and a preheated air having a lower oxygen concentration than the high-concentration oxygen. Further, an air supply device 26 for supplying compressed air at a regulated supply amount and a high-concentration oxygen supply device 23
And a mixer 29 for mixing high-concentration oxygen supplied from the air supply device 26 and preheated air or compressed air. The high-concentration oxygen supply device 23 has an oxygen concentration of 90.
It is composed of an oxygen tank 24 filled with high-concentration oxygen of at least% (specifically, about 93%) and a flow control valve 25. The air supply device 26 includes an air tank 27 filled with preheated air or compressed air, and a flow control valve 28. 30 and 31 are flow meters, respectively;
A thermometer 32 measures the temperature of the air supplied to the mixer 29.

The allowable range of the oxygen content of the combustion supporting gas is described in detail in Japanese Patent Publication No. 52-24790. That is, the weight ratio of oxygen in the combustion supporting gas to the input amount of waste is from 1.0: 0.15 to 1.0: 0.
This is an allowable range of 40. Therefore, also in this example, the oxygen content in the combustion supporting gas is adjusted within this allowable range.

In this example, a fuel supply device is constituted by a plurality of fuel supply units 22 provided individually for each burner 12, and a plurality of combustion supporting gases provided individually for each burner 12. The supply device unit 33 constitutes a combustion supporting gas supply device.

Numeral 34 denotes flow meters 20, 21, 30, 31 of the fuel supply unit 22 and the combustion support gas supply unit 33 provided individually for each burner 12.
And calculation based on the data from the thermometer 32 and the data on the supply amount of the waste supplied from the waste input device 6 to the moving bed type furnace 1, that is, the input amount, and based on the result, Fuel supply unit 22
And the flow control valve 1 of the combustion supporting gas supply unit 33
This is a control device for giving control commands to 5, 18, 25, and 28. The control unit 34 controls the waste direct melting furnace based on data on the supply amount of the waste to be supplied to the moving bed furnace 1 obtained from the waste input device 6, that is, the input amount (for example, the number of inputs per unit time). Is determined. In general, the design amount is determined based on a large amount of waste treatment. For example, the supply amount of waste supplied from the waste input device 6 to the moving bed furnace 1 is 80% or less of the design amount. Is determined to be a low load, and when the supply amount of waste is larger than 80% of the design amount, it is determined to be a steady load. Needless to say, the load criterion may be further refined. If the control device 34 determines that the load state is low, the control device 34 determines whether the injection energy from the plurality of burners 12 (total injection energy of the combustion support gas and fuel injected from the burners) is equal to the plurality of burners 12 at the steady load. Each of the combustion supporting gas supply units 33 is set so as to be at least 80% of the injection energy from the burners 12 and so that the temperature of the flame emitted from each burner 12 falls within the flame temperature range of 1200 ° C. to 1800 ° C.
The control command for adjusting the oxygen concentration of the combustion supporting gas supplied from the fuel supply unit to the burner 12 and the supply amount of the combustion supporting gas and the calorific value and the fuel supply amount of the fuel supplied from the fuel supply unit 22 to the burner 12 are controlled by each flow rate control. Valves 15, 18, 2
Output to 5, 28. Here, the injection energy is defined as the product of the mass flow rate and the square of the velocity. Flow meters 20, 21,
Numerals 30 and 31 detect data relating to the mass flow rate and the velocity used for calculating the injection energy.

The condition that the injection energy from the plurality of burners 12 at a low load is 80% or more of the injection energy from the plurality of burners 12 at a steady load (at a high load) is satisfied regardless of the load variation. This is a condition for preventing the amount of gas flowing in the moving bed furnace 1 from fluctuating greatly. This is because if the amount of gas (combustion support gas + combustion exhaust gas) flowing in the moving bed furnace 1 fluctuates greatly, the furnace temperature and the furnace pressure fluctuate greatly, and the melting of waste in the moving bed furnace 1 This is to prevent the treatment from becoming unstable and preventing the upper surface level of the waste in the moving bed furnace 1 from being maintained within a predetermined range. This condition is satisfied if the combustion support gas supply amount and the fuel supply amount are always constant. When the supply amount of combustion support gas increases, the supply amount of fuel may be reduced, and when the supply amount of fuel increases, the supply amount of combustion support gas may be reduced.

The temperature of the flame emitted from each burner 12... Is set to fall within the flame temperature range of 1200 ° C. to 1800 ° C. for the following reason. When the temperature of the flame falls below 1200 ° C., the combustion supporting gas supply port 11 (in this example, the outlet of the burner 12) is partially or entirely blocked by the molten slag flowing down from the combustion and melting area 4. The lower limit of the flame temperature is 1200 ° C
That is all. In addition, when the flame temperature rises above 1800 ° C. when the oxygen content of the combustion supporting gas is adjusted according to the load variation, the flame may damage the furnace wall of the moving bed furnace 1. The upper limit of the flame temperature is set to 1800 ° C.

When the temperature of the air used for diluting the oxygen concentration is high, combustion can be performed with low-concentration oxygen. Therefore, the controller 34 also uses the temperature of the air measured by the thermometer 32 as basic data for generating control commands. ing.

Next, a specific example of the simplest operation method using this device will be described. For example, when the above-described steady load (high load) state is determined, the flow control valve 25 is opened, the flow control valve 28 is completely closed, and only high-concentration oxygen is supplied to the burner 12. At this time, the flow control valve 1
5 is opened, the flow control valve 18 is closed, and only the high calorific value fuel is supplied to the burner 12. At this time, the fuel supply amount and the combustion supporting gas supply amount are determined so that the temperature of the flame of the burner 12 does not become 1200 ° C. or less. When the low load state is determined, the flow control valve 25 is opened,
The flow control valve 28 is also opened to mix the high-concentration oxygen and air with the mixer 29.
And a combustion supporting gas having a predetermined oxygen concentration is supplied to the burner 1.
Feed to 2. In consideration of efficient thermal decomposition of waste, the limit value of this oxygen concentration is 40% at present.
It is considered above. At this time, the flow control valve 15 is closed and the flow control valve 18 is opened to supply only the low calorific value fuel to the burner 12. At this time, the opening degree of each flow control valve is, as described above, the injection energy from the plurality of burners 12.
2 may be appropriately determined so as to be 80% or more of the injection energy from. In this case, as well known, the weight ratio of oxygen in the combustion supporting gas to the amount of waste input is 1.
Of course, it must be within the allowable range of 0: 0.15 to 1.0: 0.40.

By operating as described above, when the load is low,
As the oxygen concentration decreases and the calorific value of the fuel decreases,
It is possible to prevent the temperature of the flame of the burner from becoming higher than 1800 ° C. When preheated air is used as the air, the oxygen concentration can be reduced as compared with the case where compressed air at normal temperature is used. When the oxygen concentration is reduced at such a low load,
Since the amount of high-concentration oxygen used is reduced, operating costs can be significantly reduced.

The above example is an example of responding to a load change in two stages. However, in a case of responding to a load change in multiple stages, the high calorific value fuel output from the high calorific value fuel supply device 13 and the low calorific value The fuel produced by mixing the low calorific value fuel output from the fuel supply device 16 with the mixer 19 is used. In this case, the control device 34 determines the opening of each flow control valve so as to satisfy the various conditions described above.

In the above example, the fuel supply unit 22 and the combustion support gas supply unit 33 are individually provided for each burner 12, but one fuel supply unit and a plurality of burners 12 are provided. A combustion support gas supply device may be provided, and the fuel and the combustion support gas may be supplied to the plurality of burners 12 from the fuel supply device and the combustion support gas supply device. In that case, as shown in FIG. 2, the above-described fuel supply unit 22 and combustion support gas supply unit 33 may be used as a fuel supply unit and a combustion support gas supply unit.

In the above example, the fuel supply unit 2
2, the burner itself has a function of receiving the high calorific value fuel and the low calorific value fuel from the high calorific value fuel supply unit and the low calorific value fuel supply unit and mixing them. If so, it is not necessary to provide the mixer 19 in the fuel supply unit 22.
Similarly, in the above example, the combustion supporting gas supply unit 3
In the case where the burner itself has the function of receiving the supply of high-concentration oxygen and preheated air or compressed air to mix the two, the combustion support gas supply unit 33 There is no need to provide the mixer 29.

Further, when the fuel having a high calorific value and the fuel having a low calorific value are completely switched and used as in the above-described specific example,
Since there is no need to provide the mixer 19 in the fuel supply unit 22, the output of the high calorific value fuel supply device 13 and the output of the low calorific value fuel supply device 16 are connected to the fuel supply pipe of the burner 12 via branch pipes. do it.

In the above example, both the oxygen concentration and the supply amount of the combustion support gas, and the calorific value and the fuel supply amount are adjusted. However, the oxygen concentration and the combustion support gas are adjusted without adjusting the heat generation amount and the fuel supply amount. Just by adjusting the supply amount, the temperature of the flame blown out of the burner is set within a flame temperature range that does not fix the molten slag and damage the furnace wall of the moving bed furnace 1. Of course, the amount may not be changed significantly.

[0040]

According to the present invention, a plurality of burners for simultaneously blowing out the combustion support gas and the fuel are provided at the combustion support gas supply port, and the temperature of the combustion support gas blown from the combustion support gas supply port by the flame of the burner. When the temperature is increased, the molten slag flowing down from the combustion melting region solidifies in the vicinity of the combustion supporting gas supply port, and it is possible to prevent the combustion supporting gas supply port from being partially blocked by the solidified molten slag.
As a result, the amount of gas supplied from the combustion supporting gas supply port can be suppressed from fluctuating, and the effect of stabilizing the melting treatment of waste can be obtained.

Further, according to the present invention, since the calorific value of the fuel can be adjusted, and the supply amount of the combustion supporting gas and the fuel supply amount can be adjusted, the calorific value of the fuel can be reduced at a low load. It is possible to prevent an increase in the temperature of the flame of the burner and to suppress a fluctuation in the amount of gas flowing in the moving bed type furnace.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an example of an embodiment of a waste direct melting furnace of the present invention.

FIG. 2 is a diagram showing a connection relationship between a fuel supply device and a combustion supporting gas supply device used in another embodiment of the waste direct melting furnace of the present invention and a plurality of burners.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Moving bed type furnace 4 Combustion melting area 5 Waste supply port 10 Combustion support gas supply port 12 Burner 13 High calorific value fuel supply device 16 Low calorific value fuel supply device 22 Fuel supply device unit 23 High concentration oxygen supply device 26 Air supply Apparatus 33 Combustion support gas supply unit 34 Control unit

Claims (13)

[Claims] 1. A waste inlet in an upper portion of an upper wall portion or a peripheral wall portion, and a peripheral portion of the peripheral wall portion located in a lower portion of a combustion and melting region where the waste is burned and melted. A moving bed type furnace having a plurality of combustion supporting gas supply ports at predetermined intervals; a waste input device for feeding the waste into the moving bed type furnace from the waste input port; And a combustion support gas supply device for supplying a combustion support gas into the moving bed type furnace from the combustion support gas supply port of the waste direct melting furnace, provided in each of the plurality of combustion support gas supply ports. A plurality of burners for simultaneously blowing out the combustion support gas and the fuel, and a fuel supply device for supplying fuel to the plurality of burners, wherein the plurality of combustion support gas supply ports are formed by molten slag flowing down from the combustion melting region. Partially Or the combustion support gas supply device and the fuel supply device supply the combustion support gas and the fuel to the plurality of burners so as to blow out a flame from the plurality of burners that prevents the burners from being totally blocked. A waste direct melting furnace, characterized in that: 2. The combustion support gas supply device is configured such that an oxygen concentration and a combustion support gas supply amount are adjustable, and the fuel supply device is configured to control a calorific value and a fuel supply amount of the supplied fuel. The direct waste melting furnace according to claim 1, wherein the furnace is adjustable. 3. The combustion supporting gas supply device and the fuel supply device may have a flame temperature range in which the temperature of the flame blown out from the burner does not fix the molten slag and does not damage the furnace wall of the moving bed type furnace. The oxygen concentration and the supply amount of the combustion supporting gas and the heat generation amount and the fuel supply amount are adjusted or the heat generation amount is adjusted so that the amount of the gas flowing into the moving bed type furnace does not fluctuate significantly. 3. The direct waste melting furnace according to claim 2, wherein the oxygen concentration and the combustion support gas supply amount are adjusted without adjusting the fuel supply amount. 4. A high-concentration oxygen supply device for supplying a high-concentration oxygen having an oxygen concentration of 90% or more by adjusting a supply amount, and a preheating device having an oxygen concentration lower than the high-concentration oxygen. An air supply device for supplying air or compressed air by adjusting the supply amount, a mixer for mixing the high concentration oxygen supply device and the high concentration oxygen supplied from the air supply device and the preheated air or compressed air, The waste direct melting furnace according to claim 2 or 3, wherein the furnace comprises: 5. The fuel supply device according to claim 1, wherein the fuel supply device comprises a high calorific value fuel supply device for supplying a high calorific value fuel at a controlled supply amount, and a low calorific value fuel having a lower calorific value than the high calorific value fuel. A low calorific value fuel supply device that adjusts and supplies a high calorific value fuel supply device and a mixer that mixes the high calorific value fuel and the low calorific value fuel supplied from the low calorific value fuel supply device. The waste direct melting furnace according to claim 2 or 3, wherein the furnace comprises: 6. A high calorific value fuel supply device for supplying a high calorific value fuel by adjusting a supply amount, and supplying a low calorific value fuel having a lower calorific value than the high calorific value fuel. The burner controls the supply of the high heating value fuel and the low heating value fuel from the high heating value fuel supply device and the low heating value fuel supply device. The waste direct melting furnace according to claim 2 or 3, having a function of receiving and mixing the two. 7. A high-concentration oxygen supply device for supplying a high-concentration oxygen having an oxygen concentration of 90% or more by adjusting a supply amount, and a preheating device having an oxygen concentration lower than the high-concentration oxygen. An air supply device for supplying air or compressed air by adjusting the supply amount, wherein the burner supplies the high concentration oxygen and the preheated air or compressed air from the high concentration oxygen supply device and the air supply device. The waste direct melting furnace according to claim 2 or 3, having a function of receiving and mixing the two. 8. A high-concentration oxygen supply device for supplying a high-concentration oxygen having an oxygen concentration of 90% or more by adjusting a supply amount, and a preheating device having an oxygen concentration lower than the high-concentration oxygen. An air supply device for supplying air or compressed air at a regulated supply amount, and a first for mixing the high-concentration oxygen supplied from the high-concentration oxygen supply device and the air supply device and the preheated air or compressed air. A high calorific value fuel supply device for supplying a high calorific value fuel by adjusting the supply amount, and a low calorific value fuel having a lower calorific value than the high calorific value fuel. A low calorific value fuel supply device that adjusts and supplies a supply amount; and a high calorific value fuel and a low calorific value fuel supplied from the high calorific value fuel supply device and the low calorific value fuel supply device. Consisting of two mixers 4. The method according to claim 2, wherein the combustion supporting gas is supplied to the plurality of burners from the first mixer, and the fuel is supplied to the plurality of burners from the second mixer. 5. Waste direct melting furnace. 9. A waste inlet in an upper portion of the upper wall portion or the peripheral wall portion, and a circumferentially extending portion of the peripheral wall portion located below the combustion and melting region where the waste is burned and melted. A moving bed type furnace having a plurality of combustion supporting gas supply ports at predetermined intervals; a waste input device for feeding the waste into the moving bed type furnace from the waste input port; A combustion support gas supply device for supplying a combustion support gas from the combustion support gas supply port into the moving bed type furnace, and the combustion support gas and the fuel provided at each of the plurality of combustion support gas supply ports to simultaneously blow out the combustion support gas and the fuel A plurality of burners; and a fuel supply device for supplying fuel to the plurality of burners, wherein the combustion support gas supply device is configured such that an oxygen concentration and a combustion support gas supply amount are adjustable, and the fuel supply device supplies Of the fuel A method of operating a waste direct melting furnace in which a heat amount and a fuel supply amount are configured to be adjustable, wherein the plurality of combustion supporting gas supply ports are partially or entirely formed by molten slag flowing down from the combustion melting region. The combustion support gas supply device supplies the combustion support gas to the plurality of burners with the oxygen concentration, the combustion support gas supply amount, and the fuel so as to blow out a flame that blocks the combustion support from the plurality of burners. A method for operating a direct waste melting furnace, wherein the calorific value and the fuel supply amount of the fuel supplied to the plurality of burners from a supply device are set. 10. The temperature of the flame blown out from the plurality of burners according to the load state of the moving bed furnace determined from the operating state of the waste input device. The oxygen concentration and the oxygen concentration are adjusted so that the molten slag does not adhere to the furnace and does not damage the furnace wall of the moving bed type furnace, and the amount of gas flowing in the moving bed type furnace does not fluctuate significantly. Adjusting the supply amount of the combustion support gas and the heat generation amount and the fuel supply amount, or adjusting the oxygen concentration and the combustion support gas supply amount without adjusting the heat generation amount and the fuel supply amount. The method for operating a waste direct melting furnace according to claim 9. 11. The flame temperature range is 1200 ° C. to 180 °.
The method for operating a waste direct melting furnace according to claim 10, wherein the temperature is 0 ° C. 12. When the supply amount of the waste supplied from the waste input device to the moving bed type furnace becomes 80% or less of a design amount, it is determined that the load is low, and the supply amount of the waste is determined. Is greater than 80% of the design amount is determined to be a steady load, and when the load is determined to be low, the injection energy from the plurality of burners is determined by the injection energy of the plurality of burners at the steady load. Adjusting the oxygen concentration, the supply amount of the combustion supporting gas, and the heat generation amount and the fuel supply amount so as to be 80% or more and that the temperature of the flame falls within the flame temperature range of 1200 ° C. to 1800 ° C. The method for operating a waste direct melting furnace according to claim 9. 13. The direct waste according to claim 12, wherein when it is determined that the load is low, the oxygen concentration of the combustion supporting gas is reduced and the calorific value of the fuel is reduced as compared with the case of the steady load. How to operate the melting furnace.