JP2005024126A - Combustion control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform combustion control coping with a variation in the properties of treated material by predicting, in real time, the variation in the properties of the treated material beforehand. <P>SOLUTION: The water content of the treated material in a hopper 2, i.e., the treated material before being supplied into an incinerator 1 is measured by using a neutron moisture gauge 22. On the basis of the measured results, the heating value of the treated material is calculated. Then, on the basis of the heating value and various actually measured data, the supplied amount of the treated material, supplied amount of a primary combustion air, a distribution ratio, and an air temperature are calculated. On the basis of the calculated results, the moving speeds of a pusher 8 and stokers 5a, 5b, and 5c are controlled to open/close air volume regulating dampers 17a to 17g and air temperature control dampers 18a to 18g. Thereby the supplied amount of the treated material, the distributedly supply control of the primary combustion air, and the control of temperature can be performed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a combustion control method in an incinerator.
[0002]
[Prior art]
Conventionally, in an incinerator that combusts waste, etc., it is difficult to grasp the properties of the object to be treated before being supplied into the furnace, so the upstream side based on data detected downstream of the incinerator The various devices are feedback-controlled. As such feedback control, an oxygen concentration sensor installed in the flue between the exhaust gas treatment facility and the chimney is used, and residual O in the exhaust gas passing through the flue is measured. ₂ Concentration is detected and this residual O ₂ O for controlling the supply amount of secondary air for combustion so that the concentration is substantially constant ₂ Control. In an incinerator equipped with an exhaust heat recovery boiler, the amount of steam generated in the boiler (referred to as boiler evaporation) is detected using a steam amount detector installed in the boiler, and the amount of boiler evaporation is constant. Therefore, boiler evaporation amount control for controlling the supply amount of the object to be processed and the supply amount of the combustion primary air is also performed. O ₂ Control is extremely important for completely burning the object to be processed and suppressing the generation of harmful substances such as dioxins. Boiler evaporation control is important for maintaining a constant amount of combustion and for the stable supply of steam to steam-using equipment, and for the stable supply of power when generating power with a steam turbine generator. It is.
[0003]
In addition, in a dry stoker of a stoker-type incinerator, an infrared camera is provided on the ceiling wall to detect the radiation temperature of the object to be treated in the ignition start area, and the properties of the object on the dry stoker are determined based on the detection result of the infrared camera. Combustion control is also known in which determination is made and the conveyance speed of the workpiece and the supply amount of combustion gas are controlled based on the determination result (for example, Patent Document 1).
[0004]
[Patent Document 1]
Japanese Patent No. 3356946
[0005]
[Problems to be solved by the invention]
However, in the combustion control method based on feedback control based on data obtained on the downstream side of the incinerator, a time lag occurs between the detection of the data and the actual control. Therefore, there is a problem in that combustion air less than the required amount is supplied, or a too small or excessive object to be processed is supplied into the furnace. As a result, incomplete combustion due to air shortage may occur, which may lead to generation of harmful substances such as CO and dioxins. In addition, the combustion state in the furnace may become unstable, leading to unstable steam supply to the steam utilization facility due to boiler instability, and unstable power generation when a steam turbine generator is used. There is also.
[0006]
On the other hand, in the method for detecting the temperature of an object to be processed on a dry stoker, since infrared detection is performed in a severe environment filled with fume and dust, abnormalities in sensors are likely to occur, and accurate coverage is required. There is a problem that it is difficult to grasp and control the properties of the processed material.
[0007]
The present invention has been made to solve such problems, and detects changes in properties of the workpieces supplied into the furnace in real time in advance, and matches the properties of the workpieces. An object of the present invention is to provide a combustion control method that achieves optimum combustion conditions.
[0008]
[Means for solving the problems and actions / effects]
In order to achieve the above object, a combustion control method according to the present invention comprises:
Supplyed to the incinerator in an incinerator having a dust supplying means for supplying a workpiece to the incinerator, an air supplying means for supplying combustion air into the incinerator, and an air preheating means for preheating the combustion air. The moisture of the object to be processed in the previous stage is detected, the calorific value is estimated from the correlation between the detection result and the moisture obtained in advance and the calorific value of the object to be processed, and the supply of the water is based on the estimated calorific value. Feedforward control of at least one of the supply amount of the workpiece supplied by the dust means, the supply amount of the combustion air supplied by the air supply means, and the temperature of the combustion air preheated by the air preheating means It is characterized by doing.
[0009]
According to the present invention, the calorific value of the object to be treated is calculated based on the moisture of the object to be treated at the previous stage supplied to the incinerator, and based on the calorific value, the supply amount of the object to be treated and the supply of combustion air are calculated. Because it is configured to feed-forward control at least one of the quantity and the temperature of combustion air, it is possible to detect in advance real-time fluctuations in the properties of the object to be processed and respond appropriately to the fluctuations be able to. Therefore, it is possible to stabilize the combustion of the processed material by absorbing fluctuations in the properties of the processed material, thereby suppressing the generation of unburned materials such as CO and harmful substances such as dioxins, and the amount of boiler evaporation The boiler can be operated stably by minimizing the fluctuation of the boiler.
[0010]
In this invention, it is preferable that the water | moisture content of the said to-be-processed object is detected with a neutron moisture meter. By doing so, it is possible to accurately measure the water content of the object to be processed before being supplied to the incinerator.
[0011]
The incinerator is a stoker-type incinerator that distributes and supplies the combustion air into the furnace through a plurality of air supply passages each provided with an air amount adjusting means for adjusting the air amount. Each of the supply to each air supply path is based on the correlation between the heat generation amount of the processed object and the distribution ratio of the combustion air to each air supply path, the supply amount of the combustion air, and the heat generation amount of the process target. It is preferable that the air amount of the combustion air is calculated and the air amount adjusting means is feedforward controlled so as to satisfy the calculation result. By doing so, the distribution control of the combustion air to the dry stoker, the combustion stoker and the like in the stoker type incinerator can be effectively performed, so that the combustion control can be performed satisfactorily.
[0012]
Further, parameters relating to combustion fluctuations of the object to be processed are detected downstream of the incinerator, and the supply means and the air supply means are controlled so that the detected values coincide with preset values. It is preferable to use feedback control together. In this way, for example, parameters related to combustion fluctuations downstream of the incinerator, such as the amount of evaporation generated in the boiler, can always be grasped, and the detected values of these parameters reliably deviate from the allowable range. Therefore, more reliable combustion control can be realized.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Next, specific embodiments of the combustion control method according to the present invention will be described with reference to the drawings.
[0014]
FIG. 1 is a schematic configuration diagram of a combustion control apparatus according to an embodiment of the present invention, and FIG. 2 is a partially enlarged view of FIG.
[0015]
In this embodiment, a stoker-type incinerator 1 that incinerates an object to be processed is provided with a hopper 2 for storing the object to be processed adjacent to the upstream side. Further, on the downstream side of the incinerator 1, an exhaust heat recovery boiler (hereinafter simply referred to as “boiler”) 3 that performs heat recovery of the high-temperature exhaust gas generated by the incineration processing of the object to be processed is provided. The boiler 3 is provided with a generator (not shown) that performs boiler power generation using steam generated by heat recovery of the boiler 3. Further, an exhaust gas treatment facility 4 for performing a temperature reduction treatment / cleaning of the exhaust gas is provided downstream of the boiler 3, and this exhaust gas treatment facility 4 is connected to a downstream chimney ( (Not shown).
[0016]
A dust supply device 6 is installed at the lowermost portion of the hopper 2 and at the most upstream portion of the stoker 5. Here, the stoker 5 includes a drying stoker 5a that dries the object to be processed and also serves as a delivery means for the object to be processed, a combustion stoker 5b that burns the object to be processed, and a post-combustion stoker 5c. . The dust feeder 6 is a pusher type, and includes a pusher 8 reciprocated along the upper surface of the flat step 7 and a control mechanism 9 for controlling the movement of the pusher 8. Further, the dry stalker 5a and the combustion stalker 5b are provided with a control mechanism (not shown) for controlling the motion speed of both the stalkers 5a and 5b.
[0017]
A first wind box 11a and a second wind box 11b are provided below the dry stoker 5a, and third to sixth wind boxes 11c to 11f are located upstream of the combustion stoker 5b. In order. Further, a seventh wind box 11g is arranged below the post combustion stoker 5c.
[0018]
The incinerator 1 is provided with a first blower 12 for supplying combustion primary air into the furnace, and a first duct 13 is connected to the first blower 12. The first duct 13 is branched into a combustion primary air duct 13 ′ and a preheating air duct 13 ″ for supplying combustion primary air. The preheating air duct 13 ″ includes A steam preheater 14 is arranged, and the steam preheater 14 is heated by heat energy from a steam source (not shown), thereby heating the air in the preheated air duct 13 ″ ( The air in the heated air duct 13 ″ is referred to as preheated air).
[0019]
The combustion primary air supply duct 13 'is branched into first to seventh branch ducts 13a' to 13g ', and these branch ducts 13a' to 13g 'are respectively connected to the first to seventh winds. Each of the boxes 11a to 11g is connected to the bottom. On the other hand, the preheated air duct 13 "is branched into first to seventh preheated air branch ducts 13a" to 13g ", and these preheated air branch ducts 13a" to 13g "are connected to the respective branches. This is connected to the ducts 13a 'to 13g' so that preheated air is supplied to the branch ducts 13a 'to 13g' so that the primary combustion air in the branch ducts 13a 'to 13g' can be preheated. 2, in the middle of the first branch duct 13a ′ and closer to the wind box 11a than the junction with the preheated air branch duct 13a ″, A temperature sensor 15a for detecting the air temperature of the combustion primary air in the branch duct 13a ', an air flow rate sensor 16a for detecting the air amount thereof, and an air amount of the combustion primary air in the first branch damper 13a'. Air volume adjustment The dampers 17a are arranged in order from the upstream side (the first blower 12 side), and temperature sensors 15b to 15g, air flow sensors 16b to 16g, and second to seventh branch ducts 13b 'to 13g', The air amount adjusting dampers 17b to 17g are similarly arranged. On the other hand, in each of the preheating air branch ducts 13a "to 13g", the amount of preheated air supplied to each of the branch ducts 13a 'to 13g' is adjusted, thereby adjusting the air temperature of the combustion primary air. Air temperature adjusting dampers 18a to 18g are arranged respectively. The air amount adjusting dampers 17a to 17g and the air temperature adjusting dampers 18a to 18g are controlled to be opened and closed by a control mechanism (not shown).
[0020]
The incinerator 1 is provided with a second blower 19 for supplying combustion secondary air for secondary combustion into the furnace, and the second blower 19 has a damper 20 on the way. Are connected to the incinerator 1 through the duct 21. The damper 20 is controlled to be opened and closed by a control mechanism (not shown).
[0021]
A neutron moisture meter 22 for detecting the moisture of the object to be processed stored in the hopper 2 is attached to the outer surface of the hopper 2 (the attachment position is not limited). The neutron moisture meter 22 is a phenomenon in which when fast neutrons irradiated from radioactive materials collide with hydrogen atoms of the same size as neutrons, they interfere with each other and decay to become slow thermal neutrons (Fig. 3), which is a publicly known moisture meter, irradiates the object to be processed in the hopper 2 from the radioactive material in the neutron moisture meter 22 and measures the number of thermal neutrons generated at that time. By comparing this measurement result with a calibration curve of a thermal neutron beam and moisture obtained in advance, the moisture of the actual workpiece can be measured.
[0022]
The neutron moisture meter 22 is connected to a calorific value calculator 23. The calorific value calculator 23 includes a storage unit for recording correlation data between the moisture and the calorific value of the object to be processed, which is obtained in advance based on actual measurement, and the moisture-calorific value correlation data and the neutron moisture meter. The calorific value of the object to be processed in the hopper 2 is calculated based on the measured value (moisture) measured in step (1). Here, the moisture-calorific value correlation data is data unique to each plant, and is given as a straight line with a downward slope in the present embodiment (see FIG. 4).
[0023]
The boiler 3 is provided with a boiler steam flow meter 24 for detecting the amount of boiler evaporation. In addition, although illustration is omitted, residual O contained in the exhaust gas passing through the flue 4 ′. ₂ O to detect concentration ₂ Various sensors for detecting various operation data such as a sensor and a temperature sensor for detecting the temperature in the furnace are provided.
[0024]
The incinerator 1 is provided with an automatic combustion control device 30 having a data input / output unit, a storage unit, a calculation unit for performing calculations described later, and the like. The input of the automatic combustion control device 30 includes calculation data from the calorific value calculator 23, detection data from the temperature sensors 15a to 15g, air flow sensors 16a to 16g, boiler steam flow meter 24, and the like. And the supply amount etc. of the to-be-processed object supplied to the incinerator 1 are each input. Here, the supply amount of the object to be processed includes, for example, measuring the fluctuation of the level in the hopper 2 when the object to be processed is supplied into the incinerator 1 using, for example, a level meter, sensors, etc. It can be obtained by a technique.
[0025]
Further, the storage unit of the automatic combustion control device 30 includes parameters such as a set value of the boiler evaporation amount, a delay time and the like, a supply amount (per unit time) of a workpiece, a calorific value, and a boiler that are obtained in advance by actual measurement. Correlation data with evaporation, correlation data between calorific value and theoretical combustion air volume (the amount of air required to completely burn a unit mass of the object to be processed), correlation data between calorific value and air ratio, calorific value And the correlation data between the distribution ratio of the combustion primary air and the calorific value and the temperature of the combustion primary air passing through the branch ducts 13a 'to 13g' are stored in advance.
[0026]
Here, the set value of the boiler evaporation amount means that when a predetermined amount of material to be treated is supplied into the incinerator 1 and the planned boiler efficiency can be obtained, the boiler 3 This is the value of the amount of steam generated (referred to as the amount of boiler evaporation). The amount of heat input to the object to be processed is multiplied by the amount of heat generated to determine the amount of heat input to the object to be processed, and this heat input is multiplied by the boiler efficiency. Can be obtained. The delay time is the time taken from the measurement of moisture in the hopper 2 of the object to be processed until the object is actually supplied to the incinerator 1 and can be obtained based on the actual measurement. . Each correlation data is an operation mode set in advance for each calorific value of the object to be processed, and is obtained based on theoretical calculation or actual measurement data.
[0027]
The output signal of the automatic combustion control device 30 includes a control mechanism for the drying stoker 5a, a control mechanism 9 for the pusher 8, a control mechanism for the air amount adjustment dampers 17a to 17g, and a control mechanism for the air temperature adjustment dampers 18a to 18g. To be supplied. Thus, based on the calculation result in the automatic combustion control device 30 according to the flow to be described later, the supply amount control of the workpiece (speed control of the pusher 8 and each stalker 5a, 5b, 5c), the temperature control of the combustion primary air ( Air temperature adjustment dampers 18a to 18g are controlled to open and close, and combustion primary air distribution and supply control (opening and closing control of the air amount adjustment dampers 17a to 17g) is performed.
[0028]
In this embodiment, the object to be processed that has been thrown in from above the hopper 2 and dropped onto the step 7 is sequentially supplied into the incinerator 1 by the reciprocating motion of the pusher 8 and the driving of the drying stalker 5a. After primary combustion such as drying on the top, combustion on the combustion stoker 5b, and post-combustion on the post-combustion stoker 5c, it is discharged out of the system from the ash discharge section disposed below the post-combustion stoker 5c. The The exhaust gas generated by the primary combustion is raised by complete combustion upon receiving the supply of the combustion secondary air, and the exhaust heat recovery by the boiler 3 is performed, and the exhaust gas treatment facility 4 reduces the temperature and cleans the smoke. It is discharged out of the system through the road 4 'and the chimney (not shown).
[0029]
Next, combustion control according to the present embodiment will be described with reference to the flow shown in FIG.
[0030]
FIG. 5 shows a flowchart of combustion control.
[0031]
A1: The moisture of the workpiece stored in the hopper 2, that is, the workpiece of the previous stage supplied to the incinerator 1 is measured using the neutron moisture meter 22, and the measurement result is calculated as the calorific value calculator. 23.
[0032]
A2: The correlation data between the moisture and the heat generation amount of the object to be processed is called from the storage unit of the heat generation amount calculator 23, and the hopper is based on the correlation data and the measurement result (the water content of the object to be processed) in the previous step A1. 2, that is, the amount of heat generated by the previous-stage workpiece to be supplied to the incinerator 1, and the calculation result is transmitted to the automatic combustion control device 30.
[0033]
A3: Recalling the set value of the boiler evaporation amount and the correlation data of the heating value-supply amount-boiler evaporation amount from the storage unit of the automatic combustion control device 30, and the correlation data and the set value of the boiler evaporation amount After calculating the supply amount of the object to be processed from the calorific value of the object to be processed calculated in the previous step A2, and measuring the moisture content of the object to be processed (see step A1), the set delay time is calculated. It is set as a reference target value (feed forward target value) of the supply amount of the object to be processed at the time when elapses.
A4: The correlation data between the calorific value and the theoretical combustion air amount is called from the storage unit of the automatic combustion control device 30, and based on the correlation data and the calorific value of the workpiece, the theory corresponding to the properties of the workpiece The amount of combustion air (the amount of air necessary to completely burn 1 kg of the object to be treated) is calculated. At the same time, the correlation data of the calorific value and the air ratio is called from the storage unit, and the air ratio necessary for burning the workpiece is calculated from the correlation data and the calorific value of the workpiece obtained in the previous step A2. Ask. And the supply amount of a to-be-processed object, theoretical combustion air, and an air ratio are multiplied, and the total supply amount of combustion primary air is obtained.
A5: Next, the correlation data between the calorific value and the distribution ratio of the combustion primary air to the branch ducts 13a ′ to 13g ′ is called from the storage unit of the automatic combustion control device 30, and from this correlation data and the calorific value, Then, a distribution ratio corresponding to the heat generation amount of the object to be processed is obtained, and based on this distribution ratio and the total supply amount of the combustion primary air calculated in the previous step A4, the first to seventh branch ducts 13a ′ to The air quantity of each combustion primary air that passes through each of the 13g 'is calculated, and the air quantity of each combustion primary air when the set delay time has elapsed after measuring the moisture content (see step A1) is calculated. The feed forward target value is used.
[0034]
A6: Recall the correlation data between the calorific value of the object to be processed and the temperature of the combustion primary air passing through the branch ducts 13a ′ to 13g ′ from the storage unit of the automatic combustion control device 30. The temperature of each combustion primary air passing through each of the branch ducts 13a ′ to 13g ′ is calculated based on the calorific value of the object to be processed calculated in step A2, and the calculation result is subjected to moisture measurement. To the feedforward target value of the air temperature of the combustion primary air when the set delay time has elapsed.
[0035]
Each feedforward target value obtained as described above is used to execute feedforward control based on the moisture content of the workpiece detected upstream (the hopper 2) from the combustion area (combustion stalker 5b) of the workpiece. Since it is a target value, it changes in real time according to the fluctuation | variation of the property (water | moisture content, calorific value) of a to-be-processed object (refer A1, A2, A3 of FIG. 6). Therefore, by adjusting the supply amount of the object to be processed, the supply amount of the combustion primary air, and the air temperature so as to reach the respective feedforward target values, the fluctuations in the properties of the object to be processed can be accurately detected in real time. Corresponding control can be performed.
[0036]
However, in various types of combustion control based only on the feedforward target value, it is difficult to completely suppress fluctuations in combustion and boiler evaporation due to the delay time setting of the object to be processed, moisture measurement errors, and the like. Therefore, parameters related to combustion fluctuations (boiler evaporation amount, etc.) are detected, and based on the current parameters, the feed amount of the object to be processed, the combustion primary air amount, and the feedback correction amount of the combustion primary air temperature are obtained, and this correction is performed. The feedforward target value is corrected using an amount.
[0037]
A7: The amount of change in the supply amount of the object to be processed so that the boiler evaporation amount detected by the boiler steam flow meter 24 matches the set value of the above-described boiler evaporation amount, and the branch ducts 13a ′ to 13g ′. The amount of change of the passing combustion primary air is obtained based on the actual measurement, and each change amount is set as the feedback correction amount of the supply amount of the workpiece and the feedback correction amount of the air amount of the combustion primary air.
A8: After the set delay time has elapsed, the feedforward target value of the supply amount of the workpiece obtained in the previous step A3 is corrected using the feedback correction amount of the workpiece (Δ1 in FIG. 6). , Δ2, and Δ3), and the corrected target value is set as the final target value of the supply amount of the workpiece. Similarly, the feedforward target value of the air amount of the combustion primary air obtained in the previous step A5 is corrected using the feedback correction amount of the air amount of the combustion primary air, and the corrected target value is combusted. The final target value of the primary air supply amount is used. Moreover, in this embodiment, about the air temperature of the said combustion primary air, the feedforward target value of the air temperature calculated | required by previous step A6 is made into the final target value of the air temperature of combustion primary air as it is.
[0038]
A9: The supply amount of the workpiece to be supplied from the hopper 2 to the incinerator 1 is detected, and this detected value matches the final target value of the supply amount of the workpiece obtained in the previous step A8. The supply speed of the object to be processed is controlled by adjusting the movement speeds of the dust supply device 8 and the stokers 5a, 5b, and 5c.
[0039]
At the same time, the amount of air and the temperature of each combustion primary air passing through each branch duct 13a 'to 13g' detected by the air flow sensors 16a to 16g and the temperature sensors 15a to 15g are the same as the combustion primary air. The air amount adjusting dampers 17a to 17g and the air temperature adjusting dampers 18a to 18g are opened and closed so as to coincide with the final target values (see Step A8) of the air amount and air temperature, and the branch ducts 13a 'to 13g' are opened and closed. The amount of air and the air temperature of each combustion primary air that passes through are controlled.
[0040]
As described above, in the present embodiment, the feedforward target value is obtained from the moisture of the object to be processed before being supplied to the incinerator 1, and this target value can be obtained from the parameter (boiler evaporation amount) related to combustion fluctuation. Correction is performed using the feedback correction amount, and various combustion controls are performed using the corrected target value (final target value). Therefore, the change in the property of the object to be processed in the hopper 2 can be detected in advance and in real time, and the change in the property of the object to be processed can be absorbed appropriately in response to the change. This stabilizes the combustion state, suppresses the generation of harmful substances such as CO and dioxins, and stabilizes the boiler 3 while minimizing fluctuations in the amount of boiler evaporation. In addition, since the final target value includes information on the downstream side of the stoker 5, it is possible to reliably withstand fluctuations in combustion and boiler evaporation due to delay time setting values, moisture measurement errors, etc. of the feedforward target values. In response to this, it is possible to prevent the combustion state from fluctuating and to reliably prevent the boiler evaporation amount from deviating from the allowable range.
[0041]
In addition, since the neutron moisture meter 22 uses neutrons and thermal neutrons with excellent permeability as detection media, the moisture content of the object to be processed in the hopper 2 can be accurately measured while being attached to the outer wall of the hopper 2. It can be carried out. Moreover, since it is not exposed to a harsh environment, failure is unlikely to occur.
[0042]
In the present embodiment, the case where the supply control of the object to be processed and the supply / temperature control of the combustion primary air have been described. However, the air amount of the combustion secondary air can also be controlled. For this purpose, the residual O in the exhaust gas when the object to be treated having ideal properties is ideally burned in the incinerator 1. ₂ Concentrate the remaining O ₂ The concentration is stored in the storage unit of the automatic combustion control device 30 as the set value of the concentration, and the above-described O ₂ Residual O in the exhaust gas in the flue 4 'detected by the sensor ₂ The concentration is transmitted to the automatic combustion control device 30. And O ₂ Residual O in exhaust gas detected by sensor ₂ The concentration is O ₂ The damper 20 is opened and closed so as to match the set value of the concentration, and feedback control of the air amount of the combustion secondary air is performed. By doing so, the exhaust gas generated with the incineration of the object to be treated can be surely completely burned, and the generation of harmful substances such as CO and dioxins can be suppressed.
[0043]
In the present embodiment, the description has been given of the case where the air amount of the combustion primary air is uniformly controlled regardless of the position of the object to be processed. However, the feedforward target is obtained using the weight function shown in FIG. It is preferable to calculate the final target value by changing the weighting of the value and the weighting of the feedback correction amount in accordance with the position (the pusher 8 part, each stalker 5a, 5b, 5c part). Here, the weighting function increases the weight of feedforward control at a position close to the pusher 8 and the dry stoker 5a (see the solid line in FIG. 7), and feedback control at a position close to the combustion stoker 5b. It is preferable to install so as to increase the weight (see the broken line in FIG. 7). This is because, at a position close to the pusher 8 and the dry stalker 5a, the supply amount of the target object to be processed is ensured after a lapse of a certain time following the change in the property (moisture) of the object to be processed. Priority is given to ensuring the state (dryness), and in the position close to the combustion stalker 5b, priority is given to stabilizing the current combustion state and reliably preventing the boiler evaporation from deviating from the allowable range. Because. By using the final target value weighted in this way, it becomes possible to perform combustion control with higher accuracy.
[0044]
In the present embodiment, the supply control of the object to be processed and the supply control / temperature control of the combustion primary air are performed. Of these, it is possible to cope with the properties of the object to be processed by performing any one type of control or a combination of any two types.
[0045]
In the present embodiment, the combustion control method in the stoker type incinerator has been described, but the concept of the present invention can also be applied to other types of incinerators such as a fluidized furnace.
[0046]
In each of the above embodiments, the dust supply device 6 and the drying stoker 5a correspond to the dust supply means of the present invention, and the first blower 12, the first duct 13, the branch ducts 13a ′ to 13g ′, the wind box. 11a-11g respond | corresponds to the air supply means of this invention. The preheating air branch ducts 13a "to 13g" and the steam preheater 14 correspond to the air preheating means, and the air amount adjusting dampers 17a to 17g correspond to the air amount adjusting means of the present invention.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram according to an embodiment of the present invention.
FIG. 2 is a partially enlarged view of FIG. 1;
FIG. 3 is an explanatory diagram for explaining a phenomenon that occurs when a neutron collides with an H atom.
FIG. 4 is an example of correlation data between moisture and heat generation amount of an object to be processed.
FIG. 5 is a flowchart of combustion control according to an embodiment of the present invention.
FIG. 6 is an explanatory diagram for explaining a feedforward target value that changes and correction of the target value;
FIG. 7 is a diagram illustrating a weighting function.
[Explanation of symbols]
1 Stoker-type incinerator
2 Hoppers
3 boiler
4 Exhaust gas treatment equipment
5a Dried stoker
5b Combustion stoker
5c After-burning stoker
6 Dust feeder
8 Pusher
9 Control mechanism
12 First blower
13a 'to 13g' branch duct
14 Steam preheater
17a-17g Air quantity adjustment damper
18a-18g Air temperature adjustment damper
19 Second blower
20 damper
22 Neutron moisture meter
23 Calorific value calculator
24 boiler steam flow meter
30 Automatic combustion control device

Claims (4)

Supplyed to the incinerator in an incinerator having a dust supply means for supplying a workpiece to the incinerator, an air supply means for supplying combustion air into the incinerator, and an air preheating means for preheating the combustion air. The moisture of the object to be processed in the previous stage is detected, the calorific value is estimated from the correlation between the detection result and the moisture obtained in advance and the calorific value of the object to be processed, and the supply of the water is based on the estimated calorific value. Feedforward control of at least one of the supply amount of the workpiece supplied by the dusting means, the supply amount of the combustion air supplied by the air supply means, and the temperature of the combustion air preheated by the air preheating means And a combustion control method. The combustion control method according to claim 1, wherein moisture of the workpiece is detected by a neutron moisture meter. The incinerator is a stoker-type incinerator that distributes and supplies the combustion air into the furnace through a plurality of air supply passages each provided with an air amount adjusting means for adjusting the air amount. Each of the supply to each air supply path is based on the correlation between the calorific value of the processed object and the distribution ratio of the combustion air to each air supply path, the supply amount of the combustion air, and the calorific value of the process object. The combustion control method according to claim 1 or 2, wherein an air amount of the combustion air is calculated, and each air amount adjusting means is feedforward controlled so as to satisfy the calculation result. Further, parameters relating to combustion fluctuations of the object to be processed are detected downstream of the incinerator, and the supply means and the air supply means are controlled so that the detected values coincide with preset values. The combustion control method according to any one of claims 1 to 3, wherein feedback control is performed in combination.

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