JP2021173496A - Waste supply abnormality detection method, waste supply control method, waste supply abnormality detection device and waste supply control device - Google Patents

Abstract

To detect abnormality of waste supply to a combustion chamber at an early stage.SOLUTION: A waste supply abnormality detection device comprises: a learning part 45 which allows learning of a prediction model using a partial least squares regression using at least one of a measurement value relating to a waste combustion state and an operation condition of a waste combustion furnace as a predictor for predicting stagnation of waste supply, using the predictor in a predetermined period from a past time before a reference time until the reference time as an explanatory variable, and using a prediction steam generation amount which is a steam generation amount at a future prediction time after the reference time as an objective variable, by using actual values of the explanatory variable and the objective variable; a prediction part 41a which inputs data on the explanatory variable to the learned prediction model by using a current time as reference time, and obtains a prediction steam generation amount; a difference calculation part 41b which calculates a difference in the steam generation amount by subtracting the prediction steam generation amount from the steam generation amount at a past time before the prediction time; and a detection part 41c which detects the presence/absence of waste supply abnormality on the basis of the difference.SELECTED DRAWING: Figure 2

Description

The present invention relates to a waste supply abnormality detection method, a waste supply control method, a waste supply abnormality detection device, and a waste supply control device.

As a waste incinerator that burns waste in a combustion chamber and generates steam in a boiler, a grate (stoker) type incinerator of Patent Document 1 is known. In this incinerator (combustion furnace), a camera is provided at the upper part of the combustion chamber as an image pickup device for imaging the combustion state of waste in the combustion chamber. This imaging device is connected to the in-core state quantity estimation device.

The in-core state quantity estimation device has an estimation model creation unit that creates an estimation model for estimating the in-core state quantity. The estimation model creation unit performs machine learning of learning data in which the past image information obtained from the past image captured by the imaging device and the state amount corresponding to the combustion state indicated by the past image information are associated with each other for estimation. Create a model. The furnace state quantity estimation device has an input image information acquisition unit and an estimated quantity calculation unit in addition to the estimation model creation unit. The input image information acquisition unit acquires the input image information that is the input of the estimation model from the image captured by the image pickup apparatus in real time. The estimator calculation unit calculates the estimated state amount according to the combustion state indicated by the input image information based on the estimation model.

JP-A-2019-074240

By the way, since the properties of the waste supplied to the waste incinerator are non-uniform, it is not easy to supply the waste to the combustion chamber at a constant speed, and in particular, the waste is stuck and clogged in the chute. In that case, the supply of waste to the combustion chamber is stagnant and the amount of waste in the combustion chamber is temporarily insufficient, a phenomenon called "garbage withering" occurs, and after that, a large amount of waste stuck. A phenomenon called "doka dropping" occurs in which the waste is supplied to the combustion chamber at once, and the amount of waste in the combustion chamber becomes excessive. When this dust withering or dropping of dust occurs, the amount of waste supplied to the combustion chamber becomes unstable, and the combustion state of the waste changes abruptly, which makes stable combustion control extremely difficult. That is, in the automatic combustion control of the waste incinerator, it is important to detect the abnormality of the waste supply (supply abnormality) due to the withering of dust and the dropping of debris at an early stage and perform the combustion control accordingly.

However, in the technique disclosed in Patent Document 1, since the estimated state amount is calculated by inputting the input image information acquired in real time from the image captured by the imaging device into the estimation model, dust withering and doka Abnormal waste supply due to dropping will be detected after the fact. That is, since the waste supply abnormality cannot be detected at an early stage, the countermeasure against the waste supply abnormality becomes ex post facto, and the combustion control may become unstable.

In view of such circumstances, the present invention provides a waste supply abnormality detection method, a waste supply control method, a waste supply abnormality detection device, and a waste supply control that can detect an abnormality in the supply of waste to the combustion chamber at an early stage. The subject is to provide the device.

According to the present invention, the above-mentioned problems are the waste supply abnormality detection method according to the first invention, the waste supply control method according to the second invention, the waste supply abnormality detection device according to the third invention, and the fourth. It is solved by the waste supply control device according to the invention.

<First invention>
The waste supply abnormality detection method according to the first invention is a waste supply abnormality detection method for detecting an abnormality in the waste supply to the combustion chamber in a waste incinerator that burns waste in a combustion chamber and generates steam in a boiler. In the method, at least one of the measured value related to the combustion state of waste and the operating condition of the waste combustion furnace is used as a predictive factor for predicting the stagnation of waste supply, and the measurement is performed from a time past the reference time. A prediction model using partial minimum-square regression with the predictive factor for a predetermined period up to the reference time as an explanatory variable and the predicted steam generation amount, which is the amount of steam generated at the predicted time in the future from the reference time, as the objective variable. A learning step of learning using the actual values of the explanatory variable and the objective variable, and a prediction step of inputting the data of the explanatory variable into the trained prediction model with the current time as a reference time to obtain the predicted steam generation amount. A difference calculation step for calculating the difference in the amount of steam generated by subtracting the predicted amount of steam generated from the amount of steam generated in the past time from the predicted time, and a detection step for detecting the presence or absence of an abnormality in waste supply based on the difference. And.

In the first invention, the detection step detects the occurrence of an abnormality in the waste supply due to the stagnation of the waste supply in the normal supply amount to the combustion chamber when the difference is larger than a predetermined set value. It may be.

In the first invention, the waste incinerator transports the waste supplied to the combustion chamber by the dust supply device to the downstream side by the grate, and mixes gas with the outlet side of the combustion chamber. has a section, sign factors as the explanatory variable, as a measure related to the combustion state of wastes, steam generation amount of the boiler, O ₂ concentration in the boiler outlet, a lower portion of the gas mixing unit Temperature, flow rate of exhaust gas in the chimney, NOx concentration at the chimney inlet, position of the temperature center of gravity of the waste layer, oxygen consumption, combustion pattern, average temperature of the surface of the waste layer in the combustion chamber, and the waste combustion furnace. The operating conditions may be at least two of the flow rate of air blown into the gas mixing portion, the amount of air blown to the combustion chamber, the dust supply speed by the dust supply device, and the speed of the grate.

<Second invention>
The waste supply control method according to the second invention controls the amount of operation at the operation end of the waste incinerator based on each step of the waste supply abnormality detection method according to the first invention and the detection result in the detection step. It includes a control step.

<Third invention>
The waste supply abnormality detection device according to the third invention detects a waste supply abnormality detection in a waste incinerator that burns waste in a combustion chamber and generates steam in a boiler. In the device, at least one of the measured value related to the combustion state of waste and the operating condition of the waste combustion furnace is used as a predictive factor for predicting the stagnation of waste supply, and the measurement is performed from a time past the reference time. A prediction model using partial least-squared regression with the predictive factor for a predetermined period up to the reference time as the explanatory variable and the predicted steam generation amount, which is the amount of steam generated at the predicted time in the future from the reference time, as the objective variable. It is the amount of steam generated at the future predicted time by inputting the data of the explanatory variable with the current time as the reference time into the learning unit to be trained using the actual values of the explanatory variable and the objective variable and the trained prediction model. A prediction unit that obtains the predicted steam generation amount, a difference calculation unit that calculates the difference in the steam generation amount by subtracting the predicted steam generation amount from the steam generation amount at a time earlier than the predicted time, and a waste based on the difference. It is provided with a detection unit that detects the presence or absence of a supply abnormality.

<Fourth invention>
The waste supply control device according to the fourth invention includes the prediction unit, the difference calculation unit, and the control unit having the detection unit of the waste supply abnormality detection device according to the third invention, and the control unit is the detection unit. The amount of operation at the operation end of the waste incinerator is controlled based on the detection result in.

According to the present invention, it is possible to detect an abnormality in the supply of waste to the combustion chamber at an early stage.

FIG. 1 is an overall configuration diagram schematically showing an incinerator to which the waste supply control device according to the embodiment of the present invention is applied. FIG. 2 is a block diagram showing a configuration of a combustion control device and a monitoring center according to an embodiment of the present invention. FIG. 3 is a flowchart for explaining a waste supply control method according to an embodiment of the present invention. FIG. 4 is a flowchart for explaining an intervention operation in the waste supply control method according to the embodiment of the present invention.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In all the drawings of the following embodiment, the same or corresponding parts are designated by the same reference numerals. Further, the present invention is not limited to one embodiment described below.

FIG. 1 shows a grate-type waste incinerator to which the waste supply control device according to the embodiment of the present invention is applied. As shown in FIG. 1, a waste incinerator, which is a waste incinerator, includes a furnace 1 as a combustion chamber in which waste is burned, a waste inlet 2 for charging waste, and a boiler 9. The boiler 9 includes a heat exchanger 9a and a steam drum 9b installed on the downstream side of the furnace outlet 7 of the furnace 1.

The garbage thrown in from the garbage inlet 2 is conveyed to the grate 4 by the garbage supply device 3. The reciprocating motion of the grate 4 causes the dust to be agitated and moved. Combustion air is supplied from the combustion air blower 6 to the air box below the grate 4, and the dust on the grate 4 is burned while being dried by blowing the supplied combustion air, and exhaust gas and ash are generated. Will be done. The generated ash falls through the ash drop port 5 and is discharged to the outside of the furnace 1.

The total amount of combustion air supplied from under the grate 4 to the inside of the furnace 1 is adjusted by the combustion air damper 14 provided in the immediate vicinity of the combustion air blower 6. The flow rate of the combustion air supplied to each air box is adjusted by the sub-grate combustion air dampers 14a, 14b, 14c, 14d provided in the pipes that supply the combustion air to each air box. NS. That is, the ratio of the flow rates of the combustion air supplied to each of the air boxes is adjusted by the combustion air dampers 14a to 14d under the grate. In FIG. 1, the bottom of the grate 4 is divided into four air boxes along the direction of transporting the waste, and combustion air is supplied through each air box. However, the air damper for combustion under the grate is used. The number of 14a to 14d and the number of air boxes is not necessarily limited to four, and can be appropriately changed according to the scale and purpose of the waste incinerator.

Cooling air is blown into the furnace 1 by the cooling air blower 11 from the cooling air blowing port 10 provided on the furnace wall. When the cooling air is blown into the furnace 1, the unburned components in the combustion gas are further burned, and the temperature of the furnace wall is suppressed from rising excessively. The flow rate of the cooling air supplied from the cooling air inlet 10 into the furnace 1 is adjusted by the cooling air damper 15 provided in the immediate vicinity of the cooling air blower 11.

Further, along the direction of transporting the waste in the grate 4, the combustible gas generated in the waste drying process and the main combustion process on the upstream side and the flue gas generated in the post-combustion process on the downstream side are the furnace of the furnace 1. They merge at the gas mixing section provided on the outlet 7 side. The combustible gas and the flue gas that have merged in the gas mixing section are agitated and mixed again, and then secondary combustion is performed by supplying air for secondary combustion. The boiler 9 is installed on the downstream side along the waste transport direction with respect to the portion where the secondary combustion is performed (hereinafter, the secondary combustion portion). The combustion gas subjected to the secondary combustion is exhausted to the outside from the chimney 8 after the heat energy is recovered by the heat exchanger 9a of the boiler 9.

In the furnace 1, an intermediate ceiling 16 is provided at an upper position along the height direction of the furnace 1. The gas flowing in the furnace 1 is divided into a gas containing a large amount of flammable gas generated in the waste drying process and the main combustion process on the upstream side and a combustion exhaust gas generated in the post-combustion process on the downstream side by the intermediate ceiling 16. Can be divided and discharged. Specifically, the combustion exhaust gas flows through the flue below the intermediate ceiling 16 (main flue), while the gas containing a large amount of flammable gas flows through the flue above the intermediate ceiling 16 (secondary flue). .. The merging of the combustion exhaust gas and the gas containing a large amount of combustible gas in the gas mixing section further promotes the stirring and mixing of the gas in the gas mixing section. As a result, the combustion in the secondary combustion section becomes more stable, the generation of dioxins in the combustion process can be suppressed, and the generation of unburned waste can be suppressed. The intermediate ceiling 16 may not be provided in the furnace 1.

Further, thermometers as sensors for measuring the gas temperature in the furnace 1 are provided at a plurality of positions in the furnace 1. Specifically, a combustion chamber gas thermometer 17 is provided at an intermediate position between the grate 4 and the cooling air inlet 10 along the height direction of the furnace 1. A main flue gas thermometer 18 is provided at a position below the furnace outlet 7 along the height direction of the furnace 1. A furnace outlet lower gas thermometer 19 is provided at a lower position of the furnace outlet 7 along the height direction of the furnace 1. A furnace outlet central gas thermometer 20 is provided at a central position of the furnace outlet 7 along the height direction of the furnace 1. A furnace outlet gas thermometer 21 for measuring the combustion control temperature is provided at a position downstream of the furnace outlet 7 along the height direction of the furnace 1. The measured values of the temperature measured by the combustion chamber gas thermometer 17, the main flue gas thermometer 18, the furnace outlet lower gas thermometer 19, the furnace outlet middle gas thermometer 20, and the furnace outlet gas thermometer 21 are the combustion process. As a measured value, it is stored in the storage unit 34 (see FIG. 2) of the combustion control device 30. The measured temperature value stored in the storage unit 34 is transmitted from the combustion control device 30 to the monitoring center 40 and stored in the storage unit 44.

The boiler 9 is provided with a boiler outlet oxygen concentration meter 22 for measuring the concentration _{of oxygen (O 2} ) in the exhaust gas on the outlet side. At the inlet of the chimney 8, a gas concentration meter 23 for measuring the concentrations of carbon monoxide (CO) and nitrogen oxides (NO _{X) in the exhaust gas is provided.} An exhaust gas flow meter 24 for measuring the amount of exhaust gas is provided in the pipe connecting the outlet of the boiler 9 and the chimney 8. The measured values of the gas concentration and the flow rate measured by the boiler outlet oxygen concentration meter 22, the gas concentration meter 23, and the exhaust gas flow meter 24 are stored in the storage unit 34 of the combustion control device 30 as the combustion process measurement values. The measured values of the measured gas concentration and flow rate are transmitted from the combustion control device 30 to the monitoring center 40 and stored in the storage unit 44.

A combustion image capturing unit 25 is provided on the downstream side in the waste transport direction inside the furnace 1. The combustion image imaging unit 25 images the combustion state of the dust on the grate 4, and stores the captured combustion image data in the storage unit 34 of the combustion control device 30. The combustion image data stored in the storage unit 34 is transmitted from the combustion control device 30 to the monitoring center 40 at predetermined time intervals.

The combustion control device 30 includes, for example, a private line, a public communication network such as the Internet, for example, a LAN (Local Area Network), a WAN (Wide Area Network), a telephone communication network such as a mobile phone, a public line, or a VPN (Virtual Private Network). ) And the like (not shown), the monitoring center 40 is connected to the monitoring center 40 via a network (not shown).

FIG. 2 is a block diagram showing the configurations of the combustion control device 30 and the monitoring center 40. As shown in FIG. 2, the combustion control device 30 as an automatic combustion control device includes a waste quality calculation unit 31, an operation amount reference value adjustment unit 32, an operation amount reference value correction unit 33, a storage unit 34, and an operation amount adjustment unit. 35 is provided. The waste quality calculation unit 31, the operation amount reference value adjustment unit 32, the operation amount reference value correction unit 33, and the operation amount adjustment unit 35 specifically include a CPU (Central Processing Unit), a DSP (Digital Signal Processor), and an FPGA ( It is equipped with a processor such as a Field-Programmable Gate Array (Field-Programmable Gate Array) and a main storage unit (none of which is shown) such as a RAM (Random Access Memory) or a ROM (Read Only Memory). The storage unit 34 is composed of a storage medium selected from a volatile memory such as RAM, a non-volatile memory such as ROM, an EPROM (Erasable Programmable ROM), a hard disk drive (HDD, Hard Disk Drive), and a removable medium. .. The removable media is, for example, a USB (Universal Serial Bus) memory or a disc recording medium such as a CD (Compact Disc), a DVD (Digital Versatile Disc), or a BD (Blu-ray (registered trademark) Disc). be. Further, the storage unit 34 may be configured by using a computer-readable recording medium such as a memory card that can be mounted from the outside.

The storage unit 34 can store an operating system (OS), various programs, various tables, various databases, and the like for executing the operation of the combustion control device 30. Here, the various programs also include an automatic combustion control program that realizes processing based on the trained model according to the present embodiment. These various programs can also be recorded on a computer-readable recording medium such as a hard disk, flash memory, CD-ROM, DVD-ROM, or flexible disk and widely distributed.

The combustion control device 30 has, as the operation amount of each operation end, the combustion air amount, the cooling air amount, the waste supply device feed rate, and the operation amount based on the conventionally known predetermined operation amount reference value setting relational expression. Control the grate feed rate. The combustion control device 30 also controls the stop and operation of the waste supply device feed rate and the grate feed speed. The operation amount reference value setting relational expression is a relational expression between the waste incineration amount setting value or the waste quality setting value and the operation amount reference value (the operation amount target value), and includes a control parameter as a correction coefficient. The control parameter is adjusted by the operation amount reference value adjusting unit 32 so as to match the waste incinerator amount set value and the waste quality set value. When at least one of the waste incinerator set value and the waste quality set value is changed, the adjusted control parameter is set by the operation amount reference value adjusting unit 32 in response to the changed set value. Be changed. By changing the control parameter, the preset operation amount reference value is corrected.

The waste quality calculation unit 31 calculates the waste quality (low calorific value of waste) according to the set value of the incinerator amount of waste. The operation amount reference value adjusting unit 32 adjusts the operation amount reference value by adjusting the control parameters included in the operation amount reference value setting relational expression. The operation amount reference value correction unit 33 corrects the operation amount reference value adjusted by the operation amount reference value adjustment unit 32 based on a predetermined control algorithm (PID control, fuzzy operation, etc.). The storage unit 34 stores the data referred to by the waste quality calculation unit 31, the operation amount reference value adjustment unit 32, and the operation amount reference value correction unit 33. The storage unit 34 stores the preset incineration amount set value and the combustion process measurement value acquired as the combustion state amount in the furnace, in addition to the predetermined operation amount reference value setting relational expression and control algorithm. There is.

The operation amount adjusting unit 35 adjusts each operation amount of each operation end so as to follow the operation amount reference value. Specifically, the operation amount adjusting unit 35 includes a combustion air amount adjusting unit 36, an air amount ratio adjusting unit 36A, a cooling air amount adjusting unit 37, a waste supply device feed speed adjusting unit 38, and a grate feed speed adjusting unit 39. Has. The combustion air amount adjusting unit 36 adjusts the operation amount so that the combustion air amount follows the operation amount reference value (hereinafter, corrected operation amount reference value) corrected by the operation amount reference value correction unit 33. The air amount ratio adjusting unit 36A controls each of the subgrate combustion air dampers 14a to 14d to adjust the mutual ratio of the flow rates in the respective air boxes. The cooling air amount adjusting unit 37 adjusts the operation amount so that the cooling air amount follows the correction operation amount reference value. Here, the amount of combustion air and the amount of cooling air are adjusted by controlling the opening degrees of the combustion air damper 14, the subgrate combustion air dampers 14a to 14d, and the cooling air damper 15. .. The waste supply device feed speed adjusting unit 38 adjusts the operation amount so that the waste supply device feed speed follows the correction operation amount reference value. The grate feed speed adjusting unit 39 adjusts the operation amount so that the grate feed speed follows the correction operation amount reference value. When the operation amount reference value is not corrected by the operation amount reference value correction unit 33, the operation amount adjustment unit 35 adjusts each operation amount based on the uncorrected operation amount reference value.

The monitoring center 40 includes a control unit 41, an output unit 42, an input unit 43, a storage unit 44, and a learning unit 45. Specifically, the control unit 41 includes a processor such as a CPU, DSP, and FPGA, and a main storage unit (none of which is shown) such as RAM and ROM. The output unit 42 displays a combustion image in the furnace 1 on the display monitor, displays characters and figures on the screen of the touch panel display, and outputs sound from the speaker according to the control by the control unit 41. Therefore, it is possible to notify the predetermined information to the outside. The input unit 43 is configured by using a user interface such as a keyboard, input buttons, levers, a touch panel for manual input provided superimposed on a display such as a liquid crystal display, or a microphone for voice recognition. .. By operating the input unit 43, a user or the like can input predetermined information to the control unit 41. The output unit 42 and the input unit 43 may be integrated into an input / output unit, and the input / output unit may be composed of a touch panel display, a speaker microphone, or the like. The monitoring center 40 can be configured in various forms, and may be configured by, for example, a personal computer (PC), a mobile terminal, or the like.

In the present embodiment, the monitoring center 40 is configured as a device separate from the combustion control device 30, but it is not essential that the monitoring center 40 is separate from the combustion control device 30. The monitoring center 40 may be configured as a device integrated with the combustion control device 30, for example, or may be configured to be included in the combustion control device 30.

The storage unit 44 is composed of a storage medium selected from volatile memory such as RAM, non-volatile memory such as ROM, EPROM, HDD, and removable media. The removable media is, for example, a USB memory or a disc recording medium such as a CD, DVD, or BD. Further, the storage unit 44 may be configured by using a computer-readable recording medium such as a memory card that can be mounted from the outside. The storage unit 44 can store an OS, various programs, various tables, various databases, etc. for executing the operation of the monitoring center 40. Here, for various programs, a waste supply abnormality detection program using the trained prediction model according to the present embodiment, an automatic combustion control program that realizes control using the operation-learned model, and a combustion image-learned model are used. An automatic judgment processing program that realizes the judgment processing that has been performed is also included. Specifically, the storage unit 44 stores the past data 44a, the set value 44b, the prediction model 44c, the operation-learned model 44d, and the combustion image-learned model 44e. Here, the past data 44a is the data of the process value in the past from the present time. The set value 44b is a predetermined reference value used when detecting the presence or absence of an abnormality in the waste supply. The set value 44b is set to a value corresponding to, for example, the difference between the amount of steam generated when garbage is supplied into the furnace 1 with a normal supply amount and the amount of steam generated when so-called dust withering occurs. NS. The prediction model 44c is a trained prediction model generated by the learning unit 45 up to the current time. The storage unit 44 may be provided in another server capable of communicating via various networks, or may be provided in the combustion control device 30. Further, these various programs can be recorded on a computer-readable recording medium such as a hard disk, a flash memory, a CD-ROM, a DVD-ROM, or a flexible disk and widely distributed.

The control unit 41 loads the program stored in the storage unit 44 into the work area of the main storage unit and executes it, and controls each component or the like through the execution of the program to realize a function that meets a predetermined purpose. can. In the present embodiment, the execution of the program by the control unit 41 executes the processing of the prediction model 44c, the operation-learned model 44d, and the combustion image-learned model 44e, which are the programs.

The learning unit 45 uses a predictive factor, which will be described later, for a predetermined period from the current time (reference time) to the current time as an explanatory variable, and sets the predicted steam generation amount, which is the amount of steam generated at the predicted time in the future from the current time. A prediction model 44c using machine learning as an objective variable is trained using the explanatory variables and the actual values of the objective variables to generate a trained prediction model. The machine learning used in the prediction model is partial least squares regression. As the actual value of the explanatory variable, among the past data 44a stored in the storage unit 44, a predictive factor for a predetermined period is used. The predictive factor is a factor for predicting the stagnation of the supply of waste to the furnace 1. In this embodiment, at least one of the measured value related to the combustion state of waste and the operating condition of the waste combustion furnace is used as a predictive factor. The measurements associated with the combustion state of wastes, for example, steam generation amount of the boiler, O ₂ concentration at the boiler outlet temperature in the lower part of the gas mixing portion, of the exhaust gas at the chimney flow, NOx concentration in the chimney inlet, The position of the temperature center of gravity of the waste layer, the amount of oxygen consumed, the combustion pattern, the average temperature of the surface of the waste layer in the furnace 1, and the like can be mentioned. The operating conditions of the waste combustion furnace include, for example, the flow rate of air blown into the gas mixing section, the amount of air blown to the furnace 1, the dust supply speed by the dust supply device, the speed of the grate, and the like. In this embodiment, at least two of the various measured values and various operating conditions listed here are used as predictors.

Here, the "air blowing amount to the furnace 1" is the amount of various gases blown into the furnace 1, but if the furnace 1 is provided with a high-temperature air blowing port for blowing high-temperature air, The amount of high-temperature air blown is also included in the "amount of air blown to the furnace 1." The "combustion pattern" is the difference between the pressure of the blower that pushes the air into the furnace and the pressure inside the furnace that pushes the air, in other words, the air pressure that is lost when the air is blown from the grate. It is a value calculated in consideration of the influence from the air flow rate and the cross-sectional area of the air inlet. This "burning pattern" reflects the weight of the waste on the grate.

As will be described later, the generated learned prediction model is used for detecting the waste supply abnormality executed by the control unit 41. The trained prediction model is stored in the storage unit 44 as the prediction model 44c. In addition, the trained prediction model may be generated (updated) on a regular basis. In this case, the prediction model 44c will be updated according to the newly generated trained prediction model.

The control unit 41 includes a prediction unit 41a for detecting a waste supply abnormality, a difference calculation unit 41b, and a detection unit 41c. The prediction unit 41a inputs explanatory variable data using the current time as a reference time into the prediction model 44c (learned prediction model) trained by the learning unit 45, and predicts the amount of steam generated at the predicted time in the future from the current time. Ask for. The difference calculation unit 41b calculates the difference in the amount of steam generated by subtracting the predicted amount of steam generated from the amount of steam generated at the current time. Here, the "current time" and the "predicted time" are times having no time width, but instead of these, a predetermined period including the time may be used. In this case, the "steam generation amount at the current time" can be obtained, for example, as a weighted average value of the steam generation amount in a predetermined period including the current time. Further, the "steam generation amount at the predicted time" can be obtained as, for example, a weighted average value of the steam generation amount in a predetermined period including the predicted time. When the difference calculated by the difference calculation unit 41b is larger than the predetermined set value 44b, the detection unit 41c causes a waste supply abnormality due to a stagnation of the waste supply to the furnace 1 with a normal supply amount. Detects the presence. When a waste supply abnormality is detected, the output unit 42 may notify the operator that the supply abnormality has occurred, such as by displaying it on a display.

As will be described later, when the detection unit 41c detects a waste supply abnormality, the control unit 41 operates the incinerator based on the operation-learned model 44d from the automatic combustion control (ACC) by the combustion control device 30. Switch to control. Here, a method of generating the operation-learned model 44d, which is a program stored in the storage unit 44, will be described. That is, the operation-learned model 44d returns to the automatic combustion control from the judgment condition for performing the intervention operation, the operation amount at the time of the intervention operation, and the intervention operation in the intervention operation control obtained from the experience of the operator in the operation management work of the incinerator. It is generated by deriving the return conditions at the time of operation by cluster analysis. For example, the points at which the speed of the grate 4 is increased or decreased by the operation of the operator can be extracted by cluster analysis from the relationship between the combustion control temperature and the combustion chamber temperature, or the combustion control temperature and the NO _x concentration. Extract from relationships by cluster analysis.

The data used to generate the operation-learned model 44d includes not only the speed of the grate 4, but also the process value obtained from the sensor related to combustion control as learning sensor information, and the operation management calculated from the process value. Includes values used in the control of, combustion quantification data, etc. The combustion quantification data is combustion quantification data in which the combustion state obtained by the combustion image-learned model 44e is quantified from the combustion image periodically obtained by the combustion image imaging unit 25. The data used to generate the operation-learned model 44d further includes a control value by the combustion control device 30 as a learning control value. These learning sensor information and learning control values serve as learning input parameters when the operation-learned model 44d is generated.

The learning output parameter when the operation-learned model 44d is generated is a correction amount obtained from the control value operated by the operator. Further, the learning output parameters are determined by the start timing of switching the control mode between the automatic combustion control by the combustion control device 30 and the control by the monitoring center 40 when the operator performs the intervention operation, and by the monitoring center 40 after the control mode is switched. It includes parameters for the duration of control and the end timing of control by the monitoring center 40.

Further, the learning unit 45 of the monitoring center 40 derives the correlation of data when the operator performs an intervention operation from the above-mentioned learning input parameters and learning output parameters by machine learning such as cluster analysis. As a result, a driving operation pattern in which the operator performs an intervention operation is generated as an operation-learned model 44d. The generated operation-learned model 44d is stored in the storage unit 44. The control unit 41 executes control of various intervention operations according to the driving operation pattern by the operation-learned model 44d generated by the learning unit 45. It should be noted that the operation-learned model 44d may be generated by deriving the correlation of the data when the operator performs the intervention operation by performing machine learning such as cluster analysis on another computer or the like. In this case, the generated operation-learned model 44d is supplied to the learning unit 45 from the computer that has performed machine learning, and is stored in the storage unit 44. In addition to machine learning, the correlation may be derived by a statistical method such as an average, a quartile, or a correlation analysis to generate an operation-learned model 44d. That is, the points of judgment of the start and end of intervention operations performed by multiple operators by analyzing multiple conditions related to complex intervention operations in which judgment is different for each operator by at least one of machine learning and statistical methods, and It is possible to extract the correction amount of each operation end set by the operator.

Further, the combustion image learned model 44e described above uses a plurality of learning combustion image data captured by the combustion image imaging unit 25 as learning input parameters. In addition, the combustion image trained model 44e quantifies the strength and weakness of the combustion state as learning output parameters, the data quantifying the position of the combustion cutoff point, and the degree of generation of unburned matter. Use the data. The combustion image trained model 44e is generated by machine learning such as deep learning, using the above-mentioned learning input parameters and learning output parameters as training data. When the combustion image is input, the combustion image trained model 44e digitizes the combustion state based on the input combustion image. Specifically, the combustion image trained model 44e classifies the combustion state into a plurality of types, for example, eight types, determines the certainty for each of the eight types, and quantifies the combustion state based on each type. I do. In addition, it may be classified into 7 types or less and more than 8 types.

Here, Table 1 shows an example of the measurement target and the operation target used in the operation-learned model 44d described above, and the parameters used.

In Table 1, the instantaneous value is a measured value at a predetermined time point, and the 1-hour average value is the value of the 1-hour moving average from the instantaneous value to 1 hour before. The difference from the target value is the difference from the instantaneous value with respect to the preset target value. A slope of a few minutes to a few tens of minutes means a slope of any of a few minutes to a few tens of minutes of an instantaneous value. The average value of several minutes to several tens of minutes means the average value of the instantaneous value in several minutes to the average value in several tens of minutes. Here, the number of minutes may be any value of 1 to 9 minutes, and the number of tens of minutes may be any value of 10 minutes to 60 minutes. The one-hour average value, the slope of several minutes to several tens of minutes, and the average value of several minutes to several tens of minutes are indicators of the fluctuation tendency in a predetermined time. The control value is a control value for each type of operating end controlled by the combustion control device 30, and the operating value is an actual value for the type of operating end being operated.

Next, a waste supply control method according to an embodiment of the present invention will be described. FIG. 3 is a flowchart showing a control operation by the combustion control device 30 and the monitoring center 40 for explaining the waste supply control method according to the present embodiment. In the flowchart shown in FIG. 3, steps ST1 to ST3 and ST5 are executed by the combustion control device 30, and step ST4 is executed by the monitoring center 40.

As shown in FIG. 3, in step ST1 executed by the combustion control device 30, the operator sets a target waste incinerator amount as an incinerator amount set value. Instead of the incinerator amount set value, the operator may set the target waste incinerator amount as the evaporation amount set value. The set incinerator amount set value is stored in the storage unit 34. As a result, automatic combustion control for the incinerator is started.

Next, in step ST2, the waste quality calculation unit 31 determines the input heat amount other than the waste such as the heat amount of the heating air for combustion, and the furnace 1 according to the waste incineration amount set value stored in the storage unit 34. Based on the planned value of the amount of heat discharged from the waste and the amount of heat recovered and recovered as steam, the waste quality, which is the lower calorific value of the waste, is calculated and set as the waste quality set value. The waste quality set value is stored in the storage unit 34.

Next, in step ST3, the operation amount reference value adjusting unit 32 is stored in the storage unit 34 based on the set value including the incineration amount set value and the waste quality set value stored in the storage unit 34. The reference value of each operation amount is calculated by referring to the operation amount reference value setting relational expression. In this way, after the operation amount reference value is set, the operation amount of each operation end is controlled so as to follow the operation amount reference value, and the waste incinerator is operated.

Next, the process proceeds to step ST4 executed by the monitoring center 40. In step ST4, the instantaneous value of the measurement target shown in Table 1 is input to the monitoring center 40 as sensor information while the furnace 1 is operating. The sensor information is the sensor information measured in the internal state of the furnace 1 and the facility related to the furnace 1, specifically, in a power generation facility for generating electric power, for example. The input sensor information is stored in the storage unit 44 as a parameter. The control unit 41 of the monitoring center 40 monitors the fluctuation of the instantaneous value of the measurement target stored in the storage unit 44, and from the instantaneous value of each measurement target input from the combustion control device 30 and read from the storage unit 44. , Calculate the parameters used.

FIG. 4 is a flowchart for explaining the determination of the intervention operation by the monitoring center 40 and the derivation of the correction amount in step ST4 of FIG. The control step is executed according to the flowchart shown in FIG. As shown in FIG. 4, first, in step ST41, the prediction unit 41a of the control unit 41 inputs the data of the explanatory variables with the current time as the reference time into the trained prediction model, and obtains the predicted steam generation amount. Next, in step ST42, the difference calculation unit 41b of the control unit 41 calculates the difference in the steam generation amount by subtracting the predicted steam generation amount from the steam generation amount at the current time. In step ST43, the detection unit 41c of the control unit 41 compares the difference calculated by the difference calculation unit 41b with the predetermined set value 44b. In step ST43, when the difference is larger than the predetermined set value 44b (step ST43: Yes), in step ST44, the detection unit 41c causes the dust supply to the furnace 1 to be stagnant at a normal supply amount, that is, so-called dust withering. Detects the occurrence of abnormal waste supply due to the problem. When the detection unit 41c detects a dust supply abnormality in step ST44, the process proceeds to step ST45. On the other hand, in step ST43, when the difference is equal to or less than the predetermined set value 44b (step ST43: No), the process returns to step ST41.

In step ST45, the control unit 41 of the monitoring center 40 switches the operation of the incinerator from the automatic combustion control (ACC) by the combustion control device 30 to the control based on the operation-learned model 44d. The control unit 41 derives a correction amount (correction operation amount reference value) for correcting the operation amount reference value based on the usage parameter.

In step ST46, the control unit 41 outputs the correction operation amount reference value. In step ST47, as shown in FIG. 2, the derived correction operation amount reference value is used in the combustion air amount adjusting unit 36, the cooling air amount adjusting unit 37, the waste supply device feed speed adjusting unit 38, and It is supplied to the operation amount adjusting unit 35 including the grate feed speed adjusting unit 39. As a result, the control unit 41 controls the combustion air damper 14, the cooling air damper 15, the sub-grate combustion air dampers 14a to 14d, the waste supply device 3, and the grate 4, which are the operation ends.

As shown in FIG. 4, when the control unit 41 reaches the upper limit of the time for ending the intervention operation based on the operation-learned model 44d (step ST48A), or the use parameter becomes a condition for ending the intervention. If (step ST48B), the process proceeds to step ST49. In step ST49, the control unit 41 switches the operation control of the incinerator from the control based on the operation-learned model 44d to the automatic combustion control (ACC) by the combustion control device 30 by ending the intervention operation.

When the processing of the monitoring center 40 is switched to the automatic combustion control by the combustion control device 30 in step ST49, the process returns to FIG. 3 and proceeds to step ST5. In step ST5, the waste quality calculation unit 31 of the combustion control device 30 determines whether or not the waste is charged. When the waste quality calculation unit 31 determines that there is waste input (step ST5: Yes), the process returns to step ST2. When the waste quality calculation unit 31 determines that no waste is thrown in (step ST5: No), the process returns to step ST4. As described above, the automatic combustion control of the incinerator using the trained model by machine learning is executed.

According to the present embodiment described above, the amount of steam generated (predicted steam generation amount) at a predicted time in the future from the current time is predicted, and the predicted amount of steam generated and the amount of steam generated at a time past the current time Based on the difference, it is possible to detect the occurrence of a waste supply abnormality due to withering of dust or the like in advance, that is, at an early stage. Therefore, when an abnormality in the supply of dust is detected, the control is immediately switched to the intervention operation, and the operation end operation is corrected by correcting the operation amount reference value at the operation end in preparation for dust withering and dropping of dust that may occur in the future. By appropriately controlling the amount, a stable combustion state can be realized.

Further, in the present embodiment, the difference calculation unit 41b of the control unit 41 calculates the difference between the steam generation amount at the current time and the predicted steam generation amount at the future predicted time. The amount of steam generated for calculating the difference from the above may be any amount of steam generated at a time earlier than the predicted time, and is not limited to the amount of steam generated at the current time. Here, the "time past the predicted time" may be a time having no time width or a predetermined period including the time. Further, when the "time past the predicted time" is the above-mentioned predetermined period, the weighted average value of the amount of steam generated in the predetermined period may be set as the "amount of steam generated at a time past the predicted time".

Further, according to the present embodiment, in the waste incinerator, the intervention operation performed by a skilled or experienced operator (hereinafter referred to as a skilled operator) at his / her own discretion is performed by, for example, cluster analysis on behalf of the skilled operator. By executing the control unit 41 based on the operation-learned model 44d, which is a program generated by machine learning, stable combustion control by the control unit 41 of the monitoring center 40 becomes possible, so that the intervention operation by the operator is greatly performed. It can be reduced to, and the operation management of the waste incinerator can be automated.

That is, while the conventional automatic combustion control is performed based only on the numerical value of the process, in the automatic combustion control according to one embodiment, the control incorporating the judgment of the combustion state similar to the judgment of the skilled operator is added. can do. As a result, it is possible to establish a technique in which the judgment of the combustion state by the human eye and skillful technique is replaced by artificial intelligence using a learned model. Therefore, combustion control including the combustion state in addition to the process signal becomes possible.

According to the present invention, the intervention condition can be determined by analyzing a large amount of actual data to determine the start of the driving intervention, the correction value of the manipulated variable reference value in the driving intervention, the end of the driving intervention, or the setting of the average intervention time.

Although one embodiment of the present invention has been specifically described above, the present invention is not limited to the above-mentioned one embodiment, and various modifications based on the technical idea of the present invention are possible. For example, the numerical values given in the above-described embodiment are merely examples, and different numerical values may be used if necessary. The invention is not limited.

For example, the input parameters and output parameters given in the above-described embodiment are merely examples, and different input parameters and output parameters may be used as necessary.

1 Reactor (combustion chamber)
3 Garbage supply device (operation end)
4 Grate (operation end)
14 Combustion air damper (operation end)
14a, 14b, 14c, 14d Air damper for combustion under the grate (operating end)
15 Cooling air damper (operation end)
41 Control unit 41a Prediction unit 41b Difference calculation unit 41c Detection unit 45 Learning unit

Claims (6)

A waste supply abnormality detection method for detecting an abnormality in the waste supply to the combustion chamber in a waste incinerator that burns waste in a combustion chamber and generates steam in a boiler.
At least one of the measured value related to the combustion state of waste and the operating condition of the waste combustion furnace is used as a predictive factor for predicting the stagnation of waste supply, and is determined from the time past the reference time to the reference time. A prediction model using the partial minimum squared regression with the predictive factor of the period as the explanatory variable and the predicted steam generation amount, which is the steam generation amount at the predicted time in the future from the reference time, as the objective variable, is obtained with the explanatory variable and the above. Learning steps to learn using the actual value of the objective variable,
A prediction step in which the data of the explanatory variables are input to the trained prediction model with the current time as the reference time to obtain the predicted steam generation amount, and
A difference calculation step of calculating the difference in the amount of steam generated by subtracting the predicted amount of steam generated from the amount of steam generated in the past time from the predicted time, and
A detection step that detects the presence or absence of an abnormality in waste supply based on the difference, and
Waste supply anomaly detection method. The claim is characterized in that when the difference is larger than a predetermined set value, the detection step detects the occurrence of an abnormality in the waste supply due to the stagnation of the waste supply in the normal supply amount to the combustion chamber. Item 1. The waste supply abnormality detection method according to item 1. The waste incinerator is designed to convey the waste supplied to the combustion chamber by a dust supply device to the downstream side by a grate, and has a gas mixing portion on the outlet side of the combustion chamber. Cage,
The predictive factors as the explanatory variables are the amount of steam generated in the boiler, the O ₂ concentration at the boiler outlet, the temperature at the lower part of the gas mixing portion, and the exhaust gas in the chimney as measured values related to the combustion state of waste. Flow rate, NOx concentration at the chimney inlet, position of the temperature center of waste layer, oxygen consumption, combustion pattern, average temperature of the surface of the waste layer in the combustion chamber, and the gas as an operating condition of the waste combustion furnace. The first or second claim, wherein the flow rate of air blown into the mixing portion, the amount of air blown to the combustion chamber, the dust supply speed by the dust supply device, and the speed of the grate are at least two. Waste supply abnormality detection method. Each step of the waste supply abnormality detection method according to any one of claims 1 to 3 and
A control step that controls the amount of operation at the operation end of the waste incinerator based on the detection result in the detection step, and
Waste supply control method. A waste supply abnormality detection device that detects an abnormality in the waste supply to the combustion chamber in a waste incinerator that burns waste in a combustion chamber and generates steam in a boiler.
At least one of the measured value related to the combustion state of waste and the operating condition of the waste combustion furnace is used as a predictive factor for predicting the stagnation of waste supply, and is determined from the time past the reference time to the reference time. A prediction model using the partial minimum-squared regression with the predictive factor of the period as the explanatory variable and the predicted steam generation amount, which is the steam generation amount at the predicted time in the future from the reference time, as the objective variable, is used as the explanatory variable and the above. A learning unit that trains using the actual value of the objective variable,
A prediction unit that inputs the data of the explanatory variables with the current time as the reference time into the trained prediction model and obtains the predicted steam generation amount, which is the steam generation amount at the future prediction time.
A difference calculation unit that calculates the difference in steam generation amount by subtracting the predicted steam generation amount from the steam generation amount in the past time from the predicted time.
A detector that detects the presence or absence of an abnormality in waste supply based on the difference,
Waste supply abnormality detection device equipped with. The waste supply abnormality detection device according to claim 5 includes the prediction unit, the difference calculation unit, and a control unit having the detection unit.
A waste supply control device in which the control unit controls the amount of operation at the operation end of the waste incinerator based on the detection result of the detection unit.

Images