JP2007271205A - Furnace situation monitoring/controlling method for melting furnace and its device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a furnace situation monitoring/controlling method for a melting furnace capable of properly grasping a furnace situation and performing proper control for a stable operation. <P>SOLUTION: In this furnace situation monitoring/controlling method of the melting furnace having a furnace main body 2 provided with a water-cooled wall 3, communicated with a secondary combustion chamber 26 at its upper portion, provided with a slag cinder notch 6 at its lower portion, introducing a thermal decomposition gas 43 generated by thermally decomposing wastes, from a thermal decomposition gas burner 4 disposed on a furnace wall, and melting ash content in the gas by combustion heat of the thermal decomposition gas, three cooling blocks composed of one or plural adjacent cooling water passages exist at an upper portion, an intermediate portion and a lower portion, and a combustion exhaust gas generating situation is monitored at the upper block 8, an auxiliary fuel supplying situation is monitored at the intermediate block 9, and a slag discharging situation is monitored at the lower block 10 on the basis of a cooling water flow rate of each cooling block, and heat absorption quantity calculated from temperature difference at an inlet and an outlet of cooling water. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a melting furnace in a gasification melting system in which waste is pyrolyzed to generate pyrolysis gas, and ash is melted by the combustion heat of the pyrolysis gas. Furthermore, the present invention relates to a method and apparatus for monitoring and controlling the in-furnace condition of a melting furnace, which enables appropriate control for stable operation of the melting furnace.

  Conventionally, a gasification and melting system is known as a technology capable of processing a wide range of wastes such as municipal waste, non-combustible waste, incineration residue, sludge, landfill waste, and the like. The gasification and melting system includes a gasification furnace that thermally decomposes and gasifies waste, and a pyrolysis gas that is provided downstream of the gasification furnace and that is generated in the gasification furnace at high temperature. It has a melting furnace that melts ash content into slag, and a secondary combustion chamber that burns exhaust gas discharged from the melting furnace. In order to reduce the waste resources, reduce the volume and make them harmless, The slag is taken out from the furnace and reused as a civil engineering material such as a roadbed material, or the waste heat is recovered from the exhaust gas discharged from the secondary combustion chamber to generate electric power (Patent Document 1, etc.).

  The melting furnace of the gasification melting system is provided with a pyrolysis gas burner for blowing the pyrolysis gas generated in the gasification furnace into the melting furnace and a combustion air supply nozzle for introducing the combustion air. Yes. The furnace body is coated on the outside with an iron skin, and the inner wall is formed of a refractory material. Since the inside of the melting furnace has a high temperature atmosphere of 1300 to 1500 ° C., a cooling water pipe or a cooling jacket is provided in the furnace wall, and the furnace wall is cooled by flowing cooling water. Then, a self-coating layer of slag cooled and solidified by this water cooling structure is formed on the inner wall surface of the furnace to prevent the refractory material from being eroded. Patent Document 2 (Japanese Patent Application Laid-Open No. 2003-161419) discloses a cooling system for a melting furnace provided with a water cooling jacket, and a plurality of blocks whose flow rates are adjusted independently by a water cooling jacket covering the outer wall of the melting furnace. A plurality of partition chambers through which cooling water flows are provided in series in each block, and the melting furnace is cooled by flowing cooling water for each of the water cooling jackets that are made into blocks. The flow rate of the cooling water is adjusted so that the outer wall of the melting furnace is cooled evenly and without excess or deficiency.

The temperature distribution in the melting furnace is not uniform, and changes depending on operating conditions such as the supply status of pyrolysis gas, auxiliary fuel or combustion air, and the amount of waste supplied. Therefore, in order to properly operate the melting furnace, it is necessary to monitor the in-furnace situation sequentially and control each operation end in accordance with this.
Therefore, a technique has been proposed in which the temperature in the furnace is measured and an operation corresponding to this is performed. For example, in Patent Document 3 (Japanese Patent Laid-Open No. 10-89653), when the furnace temperature of the melting furnace rises above a predetermined value, the combustion temperature in the melting furnace is excessively supplied by supplying low-temperature combustion air. A configuration for lowering is disclosed. A temperature sensor is used to detect the furnace temperature.

  Patent Document 4 (Japanese Patent Application Laid-Open No. 2004-183914) discloses a temperature compensation method for maintaining the temperature in the melting furnace at a temperature suitable for ashing into slag, and a temperature sensor or a television is disclosed. The temperature in the furnace is detected by a temperature monitoring means comprising a camera, and the temperature control means is controlled based on the temperature to maintain the furnace temperature at a predetermined temperature. As temperature control means, means for controlling the ratio of the amount of secondary air supplied to the melting furnace and the amount of oxygen supplied has been proposed. The TV camera performs image processing on the output and monitors the furnace temperature from the slag state in the furnace.

JP 2004-144402 A JP 2003-161419 A Japanese Patent Laid-Open No. 10-89653 JP 2004-183914 A

As described above, as one of means for monitoring the in-furnace condition of the melting furnace, a temperature sensor for measuring the in-furnace temperature is provided as described in Patent Documents 3 and 4, and the in-furnace condition is monitored based on this. There is a means to do. Conventionally, thermocouples and radiation thermometers have been used as temperature sensors. However, thermocouples can measure temperature with high accuracy, but are easily deteriorated by the atmosphere in the furnace, and particularly in a high temperature atmosphere of about 1300 ° C. to 1500 ° C., the life is shortened and is not suitable for use in a melting furnace. Although the radiation thermometer can be used even in a high temperature atmosphere, there is a problem that the reliability is low and the accuracy is lacking. Similarly, monitoring of the furnace temperature with a TV camera is also very unreliable because it is largely visually observed. In addition, the method described in Patent Document 2 aims to uniformly cool the outer wall of the melting furnace, and is configured to change the cooling flow rate based on the temperature distribution in the furnace. Not done.
Therefore, in view of the above-mentioned problems of the prior art, the present invention can accurately grasp the in-furnace condition in the melting furnace in the gasification melting system, and further, appropriate control for stable operation of the melting furnace. It is an object of the present invention to propose a method and apparatus for monitoring and controlling the state of a melting furnace in a gasification melting furnace that enables the above.

Therefore, in order to solve this problem, the present invention provides:
Pyrolysis gas generated by pyrolyzing waste, having a furnace body with a water-cooled wall outside the refractory wall, the upper part communicating with the secondary combustion chamber, the lower part with a slag outlet In a melting furnace in-furnace situation monitoring and control method for introducing ash from the pyrolysis gas burner provided on the furnace wall and melting the ash in the gas by the combustion heat of the pyrolysis gas,
The cooling water passage of the water cooling wall is divided into a plurality in the vertical direction, and there are a plurality of cooling blocks composed of one or a plurality of the cooling water passages adjacent to each other,
It is characterized in that the in-furnace situation of the part corresponding to each block is monitored based on the temporal change of the endothermic amount calculated from the cooling water flow rate in each cooling block and the temperature difference between the inlet side and the outlet side of the cooling water. .

According to the present invention, the temperature change in the furnace can be grasped accurately and in real time by obtaining the transition of the heat absorption amount from the product of the cooling water flow rate and the temperature difference for each cooling block. Furthermore, since the temperature change can be detected for each of the plurality of cooling blocks arranged in the vertical direction, the situation in each part of the melting furnace can be appropriately monitored.
In addition, as the wall thickness of the fire wall decreases, the endotherm of the cooling water increases, so erosion of the fire wall can be detected and the amount of heat absorbed is measured for each block. Wall repair and maintenance become easy.

It also has a furnace body with a water-cooled wall on the outside of the refractory wall, the upper part communicates with the secondary combustion chamber, the lower part has a slag outlet, and heat generated by pyrolyzing waste In the method for monitoring and controlling the in-furnace situation of a melting furnace in which cracked gas is introduced from a pyrolysis gas burner provided on the furnace wall, and the ash content in the gas is melted by the combustion heat of the pyrolysis gas,
The cooling water passage of the water cooling wall is divided into a plurality in the vertical direction, and there are three cooling blocks composed of one or a plurality of adjacent cooling water passages in the upper part, the middle part, and the lower part,
Calculate the endothermic amount in each cooling block from the cooling water flow rate in each cooling block and the temperature difference between the inlet side and the outlet side of the cooling water, and based on the calculated endothermic amount, in the upper block, the state of combustion exhaust gas generation, In the middle block, the auxiliary fuel supply status is monitored, and in the lower block, the slag output status is monitored.

  In the present invention, three cooling blocks, upper, middle, and lower, are arranged in the vertical direction, and by obtaining the endothermic amount obtained from each cooling block, monitoring of gas amount fluctuation in the melting furnace, detection of overload of auxiliary fuel, It becomes possible to simultaneously monitor the blockage of the slag outlet.

The auxiliary fuel supply amount is mainly controlled when the endothermic amount shows an abnormal value in the intermediate block.
The intermediate block corresponds to a combustion zone in the furnace, and when the endothermic amount shows an abnormal value, it can be determined that the combustion state is not good. For example, when the endothermic amount shows an abnormally high value, it can be determined that the combustion temperature is too high due to an excessive supply amount of auxiliary fuel.
Therefore, by adjusting the auxiliary fuel supply amount as in the present invention, it is possible to maintain a good combustion state, and it is possible to optimize the auxiliary fuel supply amount, thereby enabling economical operation. .

Furthermore, when the endothermic amount shows an abnormal value in the upper block, at least one of the combustion air amount, the waste supply amount, and the auxiliary fuel supply amount is controlled.
The upper block corresponds to the exhaust gas outlet side of the melting furnace, and when this endothermic value shows an abnormal value, for example, when the endothermic amount shows a high value, the combustion zone exists on the exhaust gas outlet side, so the amount of exhaust gas is It is estimated that it has increased. This can be determined that the amount of combustion exhaust gas has increased because the amount of combustion air, the amount of waste supplied, or the auxiliary fuel is supplied in excess of a predetermined amount. When the amount of exhaust gas increases, the gas residence time in the melting furnace and the secondary combustion chamber is short, and sufficient combustion time cannot be obtained, resulting in incomplete combustion, which causes generation of CO and DXNs.
Accordingly, as in the present invention, it is possible to stably operate the melting furnace by controlling at least one of the combustion air amount, the waste supply amount, and the auxiliary fuel and returning the exhaust gas amount to a predetermined amount.

Furthermore, when the endothermic amount shows an abnormal value in the lower block, at least one of a combustion air amount, a waste supply amount, and a burner output for heating the slag outlet is controlled. It is characterized by.
The lower block corresponds to the slag outlet of the melting furnace, and when the endothermic amount shows an abnormal value, for example, when the endothermic amount is low, the slag outlet is clogged or tends to be clogged. It can be judged. Therefore, as in the present invention, by controlling at least one of the combustion air amount, waste supply amount, and oxygen burner output, it is possible to increase the temperature near the slag outlet and prevent clogging due to slag solidification It becomes.

It also has a furnace body with a water-cooled wall on the outside of the refractory wall, the upper part communicates with the secondary combustion chamber, the lower part has a slag outlet, and it is generated by pyrolyzing waste on the furnace wall In the in-furnace situation monitoring / control device of the melting furnace, in which a pyrolysis gas burner for introducing the pyrolysis gas is provided, and the ash content in the gas is melted by the combustion heat of the pyrolysis gas,
The cooling water passage of the water cooling wall is divided into a plurality in the vertical direction, and there are three cooling blocks composed of one or a plurality of adjacent cooling water passages in the upper part, the middle part, and the lower part,
Flow rate measuring means for measuring the cooling water flow rate in each cooling block, temperature measuring means for measuring the temperatures of the inlet side and the outlet side of the cooling water, the measured cooling water flow rate and the temperature obtained from the temperature measuring means. A control means for calculating an endothermic amount from the difference,
On the basis of the heat absorption amount, combustion exhaust gas generation status is monitored in the upper block, auxiliary fuel supply status is monitored in the intermediate block, and slag outflow status is monitored in the lower block.

Further, the control means mainly controls the auxiliary fuel supply amount when the endothermic amount of the intermediate block shows an abnormal value.
Further, the control means controls at least one of a combustion air amount, a waste supply amount, and an auxiliary fuel supply amount when the endothermic amount shows an abnormal value in the upper block. To do.
Furthermore, the control means may be configured to output at least one of a combustion air amount, a waste supply amount, and a burner output for heating the slag outlet when the endothermic amount shows an abnormal value in the lower block. It is characterized by controlling one.

As described above, according to the present invention, in the melting furnace in the gasification melting system, the state in the furnace can be accurately grasped, and further, appropriate control for stable operation of the melting furnace becomes possible. .
That is, by obtaining the transition of the endothermic amount from the product of the coolant flow rate and the temperature difference for each cooling block, the temperature change in the furnace can be grasped accurately and in real time. Furthermore, since the temperature change can be detected for each of the plurality of cooling blocks arranged in the vertical direction, the situation in each part of the melting furnace can be appropriately monitored.

  In addition, there are three cooling blocks, an upper block, an intermediate block, and a lower block. By determining the amount of heat absorbed by each block, monitoring of gas amount fluctuations, detection of overload of auxiliary fuel, and monitoring of the slag outlet closure status Can be performed simultaneously. Furthermore, by performing the control corresponding to each cooling block, it is possible to optimize the auxiliary fuel supply amount, optimize the combustion position, and prevent the slag outlet from being blocked, thereby enabling economical and stable operation. .

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention unless otherwise specified, but are merely illustrative examples. Not too much.
FIG. 1 is a configuration diagram of a melting furnace provided with an in-furnace monitoring / control device according to an embodiment of the present invention, and FIG. 2 is an overall configuration diagram showing an outline of a gasification melting system.

First, the schematic configuration of the gasification and melting system according to the present embodiment will be described with reference to FIG.
The waste 40 input from the waste input hopper 21 is crushed and dried as necessary, and then quantitatively supplied to the fluidized bed gasifier 23 through the dust feeder 22. In the fluidized bed gasification furnace 23, combustion air 41 having a temperature of about 120 to 230 ° C. and an air ratio of about 0.2 to 0.7 is blown into the furnace through the wind box 24 from the lower part of the furnace, and the fluidized bed temperature is 500. It is maintained at about ~ 600 ° C.
The waste 40 is pyrolyzed and gasified in the fluidized bed gasification furnace 23 and decomposed into gas, tar, and char (carbide). Tar is a component that becomes liquid at room temperature, but is present in a gaseous state in the gasification furnace.
The char is gradually pulverized in the fluidized bed and is introduced into the swirl melting furnace 1 along with gas and tar. Hereinafter, these components introduced into the swirl melting furnace 1 are collectively referred to as a pyrolysis gas 43.

The pyrolysis gas 43 discharged from the top of the fluidized bed gasification furnace 23 is introduced into the pyrolysis gas burner of the swirl melting furnace 1 through a lining duct. In the pyrolysis gas burner, pyrolysis gas 43 is mixed with combustion air 44 and introduced into the furnace to form a swirling flow. At this time, the combustion air 44 may have an air ratio of 0.9 to 1.1, preferably about 1.0.
In the swirl melting furnace 1, the mixed gas of the pyrolysis gas 43 and the combustion air 44 is combusted so that the furnace temperature is maintained at 1300 to 1500 ° C., and the ash content in the pyrolysis gas 43 is melted and slagged. The molten slag adheres and flows down on the inner wall surface of the swirl melting furnace 1 and is discharged from the slag outlet at the bottom of the furnace. The slag discharged from the slewing melting furnace 1 is rapidly cooled in the granulated water tank 28, carried out by the slag conveyor 29, and collected as granulated slag. The recovered granulated slag can be effectively used for roadbed materials and the like.

On the other hand, the combustion exhaust gas discharged from the swirl melting furnace 1 is introduced into the secondary combustion chamber 26. In the secondary combustion chamber 26, the combustion air 47 is supplied so as to have an air ratio of 1.2 to 1.5, and unburned components in the combustion exhaust gas are completely burned here.
The combustion exhaust gas is heat recovered by the boiler unit 27 and cooled to about 200 to 250 ° C. The combustion exhaust gas discharged from the boiler unit 27 is introduced into the temperature reducing tower 30 and cooled to about 150 ° C. by direct water spray. The combustion exhaust gas discharged from the temperature reducing tower 30 is sprayed with slaked lime and activated carbon in the flue as necessary, and introduced into the reaction dust collector 31. In the reaction dust collector 31, dust, acid gas, DXNs, etc. in the combustion exhaust gas are removed. The dust ash discharged from the reaction dust collector 31 is treated with chemicals and disposed of in landfill. The combustion exhaust gas is reheated by the steam heater 32 and NO _x is removed by the catalyst reactor 33, and then the attracting fan 34. Through the chimney 35 through the atmosphere.

Next, the melting furnace in the present embodiment will be specifically described with reference to FIG.
As shown in the figure, the swirl melting furnace 1 has a furnace body 2 having a circular cross section, and one or more pyrolysis gas burners 4 for blowing a pyrolysis gas 43 are provided on the side wall of the furnace body 2. The pyrolysis gas burner 4 is provided with a combustion air supply nozzle 5 for introducing combustion air (primary air) 44. Further, an auxiliary burner 12 is disposed in the vicinity of the pyrolysis gas burner 4. Further, the upper part of the furnace body 2 communicates with the secondary combustion chamber 26, and the combustion exhaust gas generated in the melting furnace 1 is sent to the secondary combustion chamber 26. A slag outlet 6 is provided at the bottom of the furnace body 2. An oxygen burner 7 is provided at the slag outlet 6 so that the molten slag does not solidify and close. Although the oxygen burner 7 is not normally used, it is ignited when the slag outlet 6 is closed or has a tendency to close. Prevent clogging due to solidification.
The furnace body 2 is covered with an iron skin 20 on the outside, and the inner wall is formed of a refractory material. A water cooling wall 3 in which a plurality of cooling pipes are embedded is formed in the furnace wall protected by the refractory material so as to cool the furnace wall. Then, a self-coating layer of slag cooled and solidified by this water cooling structure is formed on the inner wall surface of the furnace to prevent erosion of the refractory material. As the refractory material, as the refractory material, a refractory brick, an irregular refractory, or the like is appropriately used.

Further, as a characteristic configuration of the present embodiment, in the water cooling wall 3 provided in the furnace body 2, the cooling water passage through which the cooling water circulates is divided into a plurality of systems in the vertical direction, and one or a plurality of adjacent cooling A plurality of cooling blocks including water passages are formed. In this embodiment, the water cooling wall 3 is divided into three cooling blocks.
Of the three cooling blocks, the upper block 8 is located in the diffuser portion of the throttle structure leading to the secondary combustion chamber 26 of the furnace body 2, the intermediate block 9 is located in the straight body portion of the furnace body 2, and the lower block 10 is Located at the bottom of the furnace. At this time, the upper, middle, and lower cooling blocks may be provided separately (with other cooling water passages between them) or may be provided adjacent to each other. It is preferable that the water cooling pipe which is a cooling water channel | path is arrange | positioned along the circumference of a furnace wall.

The cooling water path may be branched into three systems on the cooling water inlet side as shown in the figure, and the branched cooling waters 11a to 11c may be supplied to the respective cooling blocks, or completely independent from the inlet side. The three circulation systems may be used.
Each of the cooling water passages is provided with a detector for detecting the cooling water flow rate and the temperature difference. A thermometer 11A that measures the temperature of the cooling water 11 is provided on the inlet side. The upper block 8 is provided with a thermometer 13 for measuring the outlet side temperature of the cooling water 11a ′ and a flow meter 14 for measuring the cooling water flow rate. Similarly, in the intermediate block 9, a thermometer 15, a flow meter 16, and a lower part are provided. In the block 10, a thermometer 17 and a flow meter 18 are provided.

  The coolant flow rate and temperature information from each cooling block are sent to the control device 19. Then, the controller 19 calculates an endothermic amount from the cooling water flow rate and the inlet / outlet temperature difference for each cooling block. That is, in the upper block 8, the difference ΔT (T′−T) between the temperature T measured by the inlet side thermometer 11 </ b> A and the temperature T ′ detected by the outlet side thermometer 13 and the flow meter 14 measured. The amount of heat absorption Q is obtained from the product of the cooling water flow rate F. Similarly, the endothermic amount is obtained for the intermediate block 9 and the lower block 10. Then, the in-furnace situation at the in-furnace portion corresponding to each cooling block is monitored based on the amount of heat absorbed. At this time, it is preferable to determine an abnormality in the furnace based on a temporal change in the endothermic amount. Further, an appropriate range of the endothermic amount may be set in advance, and an abnormality in the furnace may be determined when the endothermic amount deviates from the appropriate range.

As described above, according to this configuration, the temperature change in the furnace can be grasped accurately and in real time by obtaining the transition of the heat absorption amount from the product of the cooling water flow rate and the temperature difference for each cooling block. Furthermore, since the temperature change can be detected for each of the plurality of cooling blocks arranged in the vertical direction, the situation in each part of the melting furnace 1 can be appropriately monitored.
In addition, as the wall thickness of the fire wall decreases, the endotherm of the cooling water increases, so erosion of the fire wall can be detected and the amount of heat absorbed is measured for each block. Wall repair and maintenance become easy.

Furthermore, specific examples of in-furnace monitoring and control in each cooling block are shown below.
The intermediate block 9 corresponds to a combustion zone in the furnace, and when the endothermic amount at this portion shows an abnormal value, it can be determined that the combustion state is not good because the supply state of the auxiliary fuel 45 is not appropriate. For example, when the endothermic amount shows an abnormally high value, it can be determined that the combustion temperature is too high due to an excessive supply amount of the auxiliary fuel 45.
Thus, the intermediate block 9 monitors the supply status of the auxiliary fuel 45 based on the amount of absorbed heat. A temporal change in the heat absorption amount in the intermediate block 9 is measured, and based on this, the quality of the auxiliary fuel supply status is judged. In addition, an appropriate range of the endothermic amount during normal operation may be set in advance, and when the endothermic amount is not within the appropriate range, it may be determined that the supply amount of the auxiliary fuel 45 is not appropriate.
When the endothermic amount shows an abnormal value, if the heat absorption amount is larger than the normal range, the supply amount of the auxiliary fuel 45 is excessive. On the other hand, if the heat absorption amount is smaller than the normal range, the supply amount of the auxiliary fuel 45 is insufficient. It can be judged that.
Furthermore, it is preferable to control the auxiliary fuel supply amount according to the heat absorption amount of the intermediate block 9. When the heat absorption amount is large, the auxiliary fuel supply amount is reduced, and when the heat absorption amount is small, the auxiliary fuel supply amount is increased. As described above, by adjusting the auxiliary fuel supply amount, it is possible to maintain a good combustion state, and it is possible to optimize the auxiliary fuel supply amount, which enables economical operation.

The upper block 8 corresponds to the exhaust gas outlet side of the melting furnace 1, and when the endothermic amount of this part shows an abnormal value, for example, when the endothermic amount shows a high value, the combustion zone exists on the exhaust gas outlet side. Therefore, it is estimated that the amount of combustion exhaust gas generated has increased. This can be determined that the amount of combustion exhaust gas has increased because the amount of combustion air, the amount of waste supplied, or the auxiliary fuel is supplied in excess of a predetermined amount. When the amount of exhaust gas increases, the gas residence time in the melting furnace and the secondary combustion chamber is short, and sufficient combustion time cannot be obtained, resulting in incomplete combustion, which causes generation of CO and DXNs.
Thus, the upper block 8 monitors the combustion exhaust gas generation status based on the heat absorption amount. As in the intermediate block 9, this may detect an abnormal state from a temporal change in the endothermic amount, or may detect an abnormal state from a preset appropriate range of the endothermic amount.
More preferably, at least one of the combustion air amount, the waste supply amount, and the auxiliary fuel supply amount is controlled so that the exhaust gas amount becomes appropriate according to the heat absorption amount of the upper block 8. Thereby, the amount of exhaust gas can be returned to a predetermined amount, and stable operation of the melting furnace becomes possible.

In the lower block 10, it corresponds to the slag outlet 6 of the melting furnace 1, and when the endothermic amount of this part shows an abnormal value, for example, when the endothermic amount is low, the slag outlet 6 is closed. It can be determined that the device has a tendency to block or is obstructed.
As described above, the lower block 10 monitors the slag outflow condition based on the endothermic amount. As with the intermediate block 9 and the upper block 8, this may detect an abnormal state from a temporal change in the endothermic amount, or may detect an abnormal state from a preset appropriate range of the endothermic amount.
More preferably, at least one of the combustion air amount, the waste supply amount, and the oxygen burner 7 output is controlled according to the heat absorption amount of the lower block 10. As a result, the temperature in the vicinity of the slag outlet is increased, and blockage due to slag solidification can be prevented.

It is a block diagram of the melting furnace provided with the in-furnace monitoring and control apparatus which concerns on the Example of this invention. It is a whole lineblock diagram showing the outline of a gasification fusion system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Melting furnace 2 Furnace main body 3 Water cooling wall 4 Pyrolysis gas burner 5 Combustion air nozzle 6 Slag outlet 7 Oxygen burner 8 Upper block 9 Middle block 10 Lower block 12 Auxiliary burner 11A, 13, 15, 17 Thermometer 14, 16, 17 Flow meter 19 Control device 23 Gasification furnace 26 Secondary combustion chamber

Claims (9)

Pyrolysis gas generated by pyrolyzing waste, having a furnace body with a water-cooled wall outside the refractory wall, the upper part communicating with the secondary combustion chamber, the lower part with a slag outlet In a melting furnace in-furnace situation monitoring and control method for introducing ash from the pyrolysis gas burner provided on the furnace wall and melting the ash in the gas by the combustion heat of the pyrolysis gas,
The cooling water passage of the water cooling wall is divided into a plurality in the vertical direction, and there are a plurality of cooling blocks composed of one or a plurality of the cooling water passages adjacent to each other,
It is characterized in that the in-furnace situation of the part corresponding to each block is monitored based on the temporal change of the endothermic amount calculated from the cooling water flow rate in each cooling block and the temperature difference between the inlet side and the outlet side of the cooling water. In-furnace condition monitoring and control method for melting furnaces. Pyrolysis gas generated by pyrolyzing waste, having a furnace body with a water-cooled wall outside the refractory wall, the upper part communicating with the secondary combustion chamber, the lower part with a slag outlet In a melting furnace in-furnace situation monitoring and control method for introducing ash from the pyrolysis gas burner provided on the furnace wall and melting the ash in the gas by the combustion heat of the pyrolysis gas,
The cooling water passage of the water cooling wall is divided into a plurality in the vertical direction, and there are three cooling blocks composed of one or a plurality of adjacent cooling water passages in the upper part, the middle part, and the lower part,
Calculate the endothermic amount in each cooling block from the cooling water flow rate in each cooling block and the temperature difference between the inlet side and the outlet side of the cooling water, and based on the calculated endothermic amount, in the upper block, the state of combustion exhaust gas generation, A method for monitoring and controlling the in-furnace situation of a melting furnace, characterized by monitoring the auxiliary fuel supply status in the intermediate block and the slag outflow status in the lower block.   The method for monitoring and controlling the in-furnace situation of a melting furnace according to claim 2, wherein the auxiliary fuel supply amount is mainly controlled when the endothermic amount shows an abnormal value in the intermediate block.   3. The melting according to claim 2, wherein when the endothermic amount shows an abnormal value in the upper block, at least one of combustion air amount, waste supply amount, and auxiliary fuel supply amount is controlled. In-furnace situation monitoring and control method.   Controlling at least one of a combustion air amount, a waste supply amount, and a burner output for heating the slag outlet when the endothermic amount shows an abnormal value in the lower block, The in-furnace condition monitoring / control method for a melting furnace according to claim 2. It has a furnace body with a water-cooled wall on the outside of the refractory wall, the upper part communicates with the secondary combustion chamber, the lower part has a slag outlet, and waste is pyrolyzed on the furnace wall. In the in-furnace situation monitoring / control device of a melting furnace provided with a pyrolysis gas burner for introducing pyrolysis gas and melting the ash in the gas by the combustion heat of the pyrolysis gas,
The cooling water passage of the water cooling wall is divided into a plurality in the vertical direction, and there are three cooling blocks composed of one or a plurality of adjacent cooling water passages in the upper part, the middle part, and the lower part,
Flow rate measuring means for measuring the cooling water flow rate in each cooling block, temperature measuring means for measuring the temperatures of the inlet side and the outlet side of the cooling water, the measured cooling water flow rate and the temperature obtained from the temperature measuring means. A control means for calculating an endothermic amount from the difference,
An in-furnace situation monitoring / control apparatus for a melting furnace, which monitors a combustion exhaust gas generation status in an upper block, an auxiliary fuel supply status in an intermediate block, and a slag discharge status in a lower block based on the heat absorption amount.   The apparatus for monitoring and controlling the in-furnace condition of a melting furnace according to claim 6, wherein said control means mainly controls the auxiliary fuel supply amount when the endothermic amount of said intermediate block shows an abnormal value.   The control means controls at least one of a combustion air amount, a waste supply amount, and an auxiliary fuel supply amount when the heat absorption amount shows an abnormal value in the upper block. Item 7. A melting furnace in-furnace condition monitoring and control device according to Item 6. The control means controls at least one of a combustion air amount, a waste supply amount, and a burner output for heating the slag outlet when the endothermic amount shows an abnormal value in the lower block. An in-furnace situation monitoring / control device for a melting furnace according to claim 6.

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