Combustion control device and combustion control method

Abstract

This reduces the amount of unburned material in the incinerator, maintains the combustion temperature within a specified range, and minimizes the generation of harmful substances from waste incineration. [Solution] A combustion control device for controlling an incinerator equipped with a grate for moving waste, comprising: an image acquisition unit that acquires image data of waste on the grate; a measurement value acquisition unit that acquires measurement values ​​from a sensor that measures exhaust gas generated by the combustion of waste in the incinerator; a determination unit that outputs the amount of unburned material in the incinerator as an evaluation value based on the image data; an operation amount calculation unit that calculates a standard operation amount based on the measurement value; an operation amount correction unit that corrects the standard operation amount based on the evaluation value and outputs it as an operation amount; and an operation end control unit that controls the operation end of the incinerator based on the operation amount.

Description

Technical Field

[0001] The present invention relates to a combustion control device and a combustion control method.

Background Art

[0002] When burning waste in an incinerator, an operator observes the combustion state inside the furnace, and if unburned waste exists, the waste is completely combusted by manual control by the operator. Automation of such control by operators is being advanced. As automation technologies, for example, there is the technology disclosed in Patent Document 1 and the technology disclosed in Non-Patent Document 1.

[0003] The combustion control device disclosed in Patent Document 1 captures an image of waste incinerated on a stoker mechanism, and determines the presence or absence of combustible lumps from the image information. When determining that there are combustible lumps, the combustion control device reduces the conveying speed of the stoker mechanism and secures combustion time for the lumps, thereby completely combusting the lumps.

[0004] The system described in Non-Patent Document 1 applies deep learning technology to combustion videos inside the furnace, thereby digitizing and outputting various indicators that operators pay attention to when judging the quality of the combustion state inside the furnace. In determining the quality of the combustion state inside the furnace, this system uses the amount of unburned waste as an indicator, adds annotations (labels) related to the indicator to the combustion videos inside the furnace, and uses a model trained by supervised learning to output an inferred value of the amount of unburned waste. Then, based on the inferred value, the feed speed of the stoker mechanism and the primary combustion air volume are adjusted to stably burn the waste.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Non-Patent Documents

[0006]

Non-Patent Document 1

[0007] From the perspective of stable operation of the incinerator, it is necessary to maintain the combustion temperature within a specified range. Furthermore, it is necessary to minimize the generation of harmful substances from the incineration of waste.

[0008] The present invention has been made in view of the above, and aims to provide a combustion control device and a combustion control method that suppress the amount of unburned material in an incinerator, maintain the combustion temperature within a predetermined range, and suppress the generation of harmful substances due to the incineration of waste. [Means for solving the problem]

[0009] A combustion control device according to an embodiment of the present invention is a combustion control device for controlling an incinerator equipped with a grate for moving waste, comprising: an image acquisition unit that acquires image data of waste on the grate; a measurement value acquisition unit that acquires measurement values ​​from a sensor that measures exhaust gas generated by the combustion of waste in the incinerator; a determination unit that outputs the amount of unburned material in the incinerator as an evaluation value based on the image data; an operation amount calculation unit that calculates a standard operation amount based on the measurement value; an operation amount correction unit that corrects the standard operation amount based on the evaluation value and outputs it as an operation amount; and an operation end control unit that controls the operation end of the incinerator based on the operation amount.

[0010] A combustion control method according to an embodiment of the present invention is a combustion control method for controlling an incinerator equipped with a grate for moving waste, which acquires image data of waste on the grate, acquires measurement values ​​from a sensor that measures exhaust gas generated by the combustion of waste in the incinerator, outputs the amount of unburned material in the incinerator as an evaluation value based on the image data, calculates a reference control amount based on the measurement value, corrects the reference control amount based on the evaluation value and outputs it as an operation amount, and controls the operation end based on the operation amount. [Effects of the Invention]

[0011] According to the present invention, it is possible to suppress the amount of unburned material in the incinerator, maintain the combustion temperature within a predetermined range, and suppress the generation of harmful substances from the incineration of waste. [Brief explanation of the drawing]

[0012] [Figure 1] This is a diagram showing a waste incineration facility according to an embodiment of the facility. [Figure 2] This is a side view showing the waste in an incinerator, the waste supply section onto the grate, and the imaging section. [Figure 3] This is a block diagram showing the configuration of a combustion control device according to this embodiment. [Figure 4] This flowchart shows the procedure for calculating the manipulated variable, which is performed by the control unit according to the embodiment. [Figure 5] This flowchart shows the procedure for the correction amount calculation process performed by the control unit according to the embodiment. [Figure 6] This diagram shows a waste incineration facility equipped with partitions that supply exhaust gas to a post-combustion grate. [Figure 7] This diagram shows a waste incineration facility that supplies exhaust gas to a post-combustion grate and does not have partitions. [Figure 8] This diagram shows a waste incineration facility that supplies combustion air to a post-combustion grate and does not have partitions. [Modes for carrying out the invention]

[0013] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Note that the present invention is not limited to the embodiments described below. In the description of the drawings, the same or corresponding elements are appropriately denoted by the same reference numerals. Furthermore, the dimensional relationships and ratios of each element in the drawings may differ from those in reality. The drawings may also include portions where the mutual dimensional relationships and ratios differ from each other.

[0014] [Embodiment] (Waste treatment system) Figure 1 is a configuration diagram showing a waste incineration facility 1 according to an embodiment of the present invention. The waste incineration facility 1 includes a waste incinerator 100, a flue 11, a dust removal device 12, a chemical supply device 13, an induced draft fan 14, a chimney 15, and a combustion control device 3.

[0015] (Waste incinerator) The waste incinerator 100 is a grate-type incinerator that incinerates waste 50. The waste incinerator 100 includes a combustion chamber 101, a waste input port 102, a waste supply device 103, and grates 1041 to 104 n , wind boxes 105a to 105c, an ash drop port 106, a furnace outlet 107, a boiler 109, a heat exchanger 109a, a steam drum 109b, a partition 113, a recirculated gas injection port 114, a secondary combustion air injection port 115, a combustion air blower 121, a combustion air supply line 122, under-grate combustion air dampers 122a to 122c, a secondary combustion air blower 123, a secondary combustion air supply line 124, a secondary combustion air damper 124a, a recirculated gas blower 125, a recirculated gas supply line 126, a recirculated gas damper 126a, a combustion chamber gas temperature sensor 131a, a main flue gas temperature sensor 131b, a furnace outlet gas temperature sensor 131c, a boiler outlet gas temperature sensor 131d, a gas concentration sensor 132, an exhaust gas flow rate sensor 133, and an imaging unit 134.

[0016] The combustion chamber 101 is a chamber in which the waste 50 is combusted.

[0017] The waste input port 102 is an input port through which the waste 50 is introduced.

[0018] The waste supply device 103 is a device that supplies the waste 50 that has been put into the waste input port 102 to the combustion chamber 101.

[0019] Fire grates 1041-104 n These are components that make up the floor of the combustion chamber 101. (Grate 1041-104) n The grates are arranged in the following order from the waste supply device 103 side, which is the upstream side of the transport of waste 50, to the ash outlet 106 side, which is the downstream side: drying grate, combustion grate, and post-combustion grate. The drying grate is a grate placed in the area where the waste 50 in the combustion chamber 101 is dried. The combustion grate is a grate placed in the area where the waste 50 in the combustion chamber 101 is burned. The post-combustion grate is a grate placed in the area where the waste 50 in the combustion chamber 101 is completely burned. Note that grates 1041-104 n Since their configurations are the same, if there is no need to distinguish between them, the subscript is omitted and they are referred to as fire grate 104.

[0020] The wind boxes 105a, 105b, and 105c are devices that supply combustion air to the grate 104. The combustion air is used to burn the waste 50 on the grate 104. Wind box 105a is located below the drying grate. Wind box 105b is located below the combustion grate. Wind box 105c is located below the post-combustion grate. The number of wind boxes located below the grate 104 can be changed as appropriate depending on the size of the waste incinerator 100.

[0021] The ash outlet 106 is the exit for the ash produced when the waste 50 is burned.

[0022] The furnace outlet 107 is the outlet for exhaust gas generated in the combustion chamber 101 by the combustion of waste 50.

[0023] Boiler 109 is a device that recovers the thermal energy of exhaust gas generated by the combustion of waste 50. Boiler 109 is equipped with a heat exchanger 109a and a steam drum 109b. Heat exchanger 109a is a device that transfers the heat of the exhaust gas flowing through boiler 109 to water. Steam drum 109b is a device that separates the steam and water generated in boiler 109.

[0024] The partition 113 is a structure that branches the flow of gas generated in the combustion chamber 101. The partition 113 is located at an upper position along the height direction of the combustion chamber 101.

[0025] The recirculation gas inlet 114 is the outlet for the recirculated gas sent to the combustion chamber 101. The recirculated gas is the exhaust gas returned to the combustion chamber 101 from the recirculation gas supply line 126, which will be described later. The recirculation gas inlet 114 is installed on the ceiling or side wall of the combustion chamber 101, and if installed on the side wall, it is installed on both side walls. In addition, one or more recirculation gas inlets 114 may be installed.

[0026] The secondary combustion air inlet 115 is the outlet for secondary combustion air. The secondary combustion air inlet 115 is located in the furnace wall at the furnace outlet 107. The secondary combustion air is air used to completely combust the combustible gas released from the waste 50.

[0027] The combustion air blower 121 is a blower that supplies combustion air. The combustion air supply line 122 is connected to the combustion air blower 121.

[0028] The combustion air supply line 122 is a pipe through which combustion air sent from the combustion air blower 121 flows. The combustion air supply line 122 is connected to the combustion air dampers 122a, 122b, and 122c below the grate.

[0029] The under-grille combustion air dampers 122a, 122b, and 122c are devices that adjust the flow rate of combustion air. Changing the opening of under-grille combustion air damper 122a changes the area of ​​the flow path connected to wind box 105a, and thus changes the flow rate of combustion air sent to wind box 105a. Changing the opening of under-grille combustion air damper 122b changes the area of ​​the flow path connected to wind box 105b, and thus changes the flow rate of combustion air sent to wind box 105b. Changing the opening of under-grille combustion air damper 122c changes the area of ​​the flow path connected to wind box 105c, and thus changes the flow rate of combustion air sent to wind box 105c. The under-grille combustion air dampers 122a, 122b, and 122c adjust the ratio of the flow rates of combustion air supplied to wind boxes 105a, 105b, and 105c, respectively.

[0030] The secondary combustion air blower 123 is a blower that supplies secondary combustion air. The secondary combustion air blower 123 supplies secondary combustion air to the secondary combustion air damper 124a.

[0031] The secondary combustion air supply line 124 is a pipe through which secondary combustion air that has passed through the secondary combustion air damper 124a flows.

[0032] The secondary combustion air damper 124a is a device that adjusts the flow rate of secondary combustion air. The secondary combustion air damper 124a is installed in the secondary combustion air supply line 124. The secondary combustion air that has passed through the secondary combustion air damper 124a flows through the secondary combustion air supply line 124 to the secondary combustion air inlet 115. Changing the opening of the secondary combustion air damper 124a changes the area of ​​the flow path in the secondary combustion air supply line 124, and thus changes the flow rate of combustion air sent to the wind box 105a.

[0033] The recirculating gas blower 125 is a blower that delivers recirculating gas. The recirculating gas blower 125 delivers the recirculating gas to the recirculating gas supply line 126.

[0034] The recirculating gas supply line 126 is a piping system that supplies recirculating gas from the recirculating gas blower 125 to the combustion chamber 101 via the recirculating gas inlet 114.

[0035] The recirculation gas damper 126a is a device that adjusts the flow rate of recirculated gas. The recirculation gas damper 126a is installed in the recirculation gas supply line 126. Changing the opening degree of the recirculation gas damper 126a changes the area of ​​the flow path in the recirculation gas supply line 126, and thus changes the flow rate of recirculated gas. Therefore, the flow rate of recirculated gas can be adjusted by adjusting the opening degree of the recirculation gas damper 126a.

[0036] The combustion chamber gas temperature sensor 131a is a temperature sensor that measures the temperature of the gas inside the combustion chamber 101. The combustion chamber gas temperature sensor 131a is located above the grate 104.

[0037] The main flue gas temperature sensor 131b is a sensor that measures the temperature of the gas flowing through the main flue below the partition 113. The main flue gas temperature sensor 131b is located below the furnace outlet 107, along the height direction of the combustion chamber 101.

[0038] The furnace outlet gas temperature sensor 131c is a sensor that measures the temperature of the exhaust gas flowing from the furnace outlet 107 to the boiler 109. The furnace outlet gas temperature sensor 131c is installed downstream of the furnace outlet 107, along the height direction of the combustion chamber 101.

[0039] The boiler outlet gas temperature sensor 131d is a sensor that measures the temperature of the exhaust gas coming out of the boiler 109. The boiler outlet gas temperature sensor 131d is installed at the outlet of the boiler 109.

[0040] The gas concentration sensor 132 is a sensor that measures the concentrations of oxygen, carbon dioxide, carbon monoxide, nitrogen oxides, and other gases contained in the exhaust gas emitted from the boiler 109. The gas concentration sensor 132 is installed at the outlet of the boiler 109.

[0041] The exhaust gas flow sensor 133 is a sensor that measures the flow rate of exhaust gas coming out of the boiler 109. The exhaust gas flow sensor 133 is installed at the outlet of the boiler 109.

[0042] The imaging unit 134 is a camera that photographs the inside of the combustion chamber 101. The imaging unit 134 is located downstream of the direction in which the waste 50 on the grate 104 is transported in the combustion chamber 101. The imaging unit 134 includes, for example, an ITV camera for imaging the waste 50 on the grate 104 for furnace monitoring, a flame-transmitting camera consisting of an infrared camera, and an image processing unit for processing the captured image data. The imaging unit 134 captures the combustion state of the waste 50 on the grate 104 and transmits the image data generated from the captured image information to the combustion control device 3.

[0043] Flue 11 is a pipe through which exhaust gas from the boiler 109 flows. A chemical supply device 13 and a dust removal device 12 are connected to flue 11.

[0044] The dust removal device 12 is a device that removes fine particles such as ash and dust contained in the exhaust gas. The dust removal device 12 collects ash and dust that are formed by the combination of pollutants contained in the exhaust gas that has flowed through the flue 11.

[0045] The chemical supply device 13 is a device that supplies chemicals to remove harmful components from exhaust gas. The chemical supply device 13 blows chemicals such as slaked lime and activated carbon into the flue 11 along with carbon dioxide.

[0046] The induced draft fan 14 is a fan that draws in exhaust gas. The induced draft fan 14 draws in exhaust gas that has been dust-removed by the dust removal device 12. The exhaust gas drawn in by the induced draft fan 14 is sent to the chimney 15.

[0047] Chimney 15 is a device that discharges exhaust gas, which has been dust-removed and had harmful substances removed with chemicals, into the air.

[0048] The waste 50 introduced from the waste input port 102 is sent into the combustion chamber 101 by a reciprocating waste supply device 103 and falls onto the grate 104. The waste 50 that falls onto the grate 104 is agitated by the reciprocating motion of the grate 104 and moves forward toward the imaging unit 134.

[0049] The waste 50 on the grate 104 is dried and burned by the blowing of combustion air supplied from wind boxes 105a, 105b, and 105c located below the grate 104. The total amount of combustion air supplied from below the grate 104 into the combustion chamber 101 is controlled by a combustion air blower 121. The flow rate of combustion air supplied to each of the wind boxes 105a, 105b, and 105c is controlled by grate-under combustion air dampers 122a, 122b, and 122c, which are installed in the piping that supplies combustion air to the wind boxes 105a, 105b, and 105c, respectively. In addition, recirculated gas is blown into the combustion chamber 101 from a recirculated gas inlet 114. By using this recirculated gas for low-air ratio combustion, the oxygen concentration in the combustion chamber 101 is reduced, thereby suppressing the generation of nitrogen oxides when the waste 50 is burned.

[0050] The gas generated by the combustion of the waste 50 is divided into two by the partition 113. Specifically, it is divided into a gas containing a large amount of combustible gas generated during the waste drying process and the main combustion process upstream of the waste 50 in the direction of transport in the grate 104, and combustion exhaust gas generated during the post-combustion process downstream. The combustion exhaust gas flows below the partition 113 (main flue), while the gas containing a large amount of combustible gas flows above the partition 113 (secondary flue). The combustion exhaust gas and the gas containing a large amount of combustible gas merge at the furnace outlet 107 of the combustion chamber 101. At the furnace outlet 107, the merging of the combustion exhaust gas and the gas containing a large amount of combustible gas further promotes gas agitation and mixing. The agitated and mixed gas undergoes secondary combustion by the supply of secondary combustion air from the secondary combustion air inlet 115. This further stabilizes the combustion of the gas at the furnace outlet 107 and suppresses the generation of dioxins during the combustion process.

[0051] The waste 50 on the grate 104 is transported while burning on the grate 104, ultimately leaving behind non-combustible ash and unburned material. The unburned material refers to the combustible waste 50 that remains unburned. The ash and unburned material remaining on the grate 104 fall through the ash outlet 106 and are discharged outside the combustion chamber 101.

[0052] The exhaust gas flowing from the furnace outlet 107 to the boiler 109 flows into the flue 11 after its thermal energy is recovered by the heat exchanger 109a of the boiler 109. Steam is generated in the boiler 109 using the heat recovered by the heat exchanger 109a. Chemicals such as slaked lime and activated carbon are blown into the flue 11 from the chemical supply device 13. When chemicals are blown into the exhaust gas, they combine with pollutants such as hydrogen chloride and sulfur oxides contained in the exhaust gas. The exhaust gas containing chemicals combined with pollutants is then collected by the dust removal device 12, which removes the chemicals, ash, and dust. After dust removal, the exhaust gas branches off, with some flowing to the recirculating gas blower 125 and the rest to the induced draft fan 14. The exhaust gas from the induced draft fan 14 is sent to the chimney 15. The exhaust gas that has passed through the chimney 15 is exhausted to the outside of the waste incineration facility 1. The exhaust gas sent to the recirculating gas blower 125 is supplied to the combustion chamber 101 from the recirculating gas supply line 126, and is then discharged from the combustion chamber 101 and circulated again. Therefore, the exhaust gas supplied to the combustion chamber 101 is called recirculating gas.

[0053] Figure 2 is a side view showing the installation state of the imaging unit 134. The imaging unit 134 is installed, for example, in a position approximately directly opposite the waste supply unit 111 and the stepped wall 112 that supply waste 50 into the combustion chamber 101. The imaging unit 134 can be installed in various positions as long as it can image at least the waste 50 on the grate 104 and the boundary portion between other objects, in this case the stepped wall 112 and the grate 104. The imaging unit 134 may be installed outside the furnace in close proximity to a window provided in the furnace wall 101a, or it may be installed inside the combustion chamber 101 with a water-cooled structure. The waste 50 introduced from the waste input port 102 is sent into the combustion chamber 101 by a reciprocating waste supply device 103. The imaging unit 134 images the waste 50 as it moves on the grate 104.

[0054] (Combustion control device) The combustion control device 3 is configured to control the waste incinerator 100. The combustion control device 3 includes a control unit 31, a storage unit 32, an interface 33, an input unit 34, and an output unit 35.

[0055] The control unit 31 is a central processing unit that integrates arithmetic and control functions. The control unit 31 includes a processor (not shown) with hardware such as a CPU (Central Processing Unit), DSP (Digital Signal Processor), and FPGA (Field-Programmable Gate Array), and a main memory unit (not shown) such as RAM (Random Access Memory) and ROM (Read Only Memory).

[0056] The memory unit 32 is a storage device that stores information. The memory unit 32 is composed of a storage medium selected from volatile memory such as RAM, non-volatile memory such as ROM, EPROM (Erasable Programmable ROM), hard disk drive (HDD), and removable media. Removable media include, for example, USB (Universal Serial Bus) memory, or disk recording media such as CD (Compact Disc), DVD (Digital Versatile Disc), or BD (Blu-ray® Disc). Alternatively, the memory unit 32 may be configured using a computer-readable recording medium such as an externally insertable memory card. The memory unit 32 can store an operating system (OS), various programs, various tables, various databases, etc., for executing the operation of the combustion control device 3. These various programs can also be recorded on computer-readable recording media such as hard disks, flash memory, CD-ROMs, DVD-ROMs, and flexible disks and widely distributed. The various programs stored in the memory unit 32 also include programs that realize processing based on a learning model. The memory unit 32 stores the unburned material determination model 32a.

[0057] Interface 33 is a device that outputs signals to control the aforementioned blowers, dampers, the drive unit for the grate 104, and the waste supply device 103, and acquires image data output by the imaging unit 134 and measurement results from the aforementioned sensors. Interface 33 receives measurement results sent from various sensors and image data transmitted from the imaging unit 134 and outputs them to the control unit 31. Interface 33 also outputs the amount of operation of the control terminals controlled by the combustion control device 3 to the control terminals. The control terminals include the drive unit for the waste supply device 103 (not shown), the drive unit for the grate 104 (not shown), various dampers, various blowers, etc.

[0058] The input unit 34 is a user interface, such as a keyboard, input buttons, or levers for operating the combustion control device 3, a touch panel for manual input superimposed on the liquid crystal display, or a microphone for voice recognition. Various types of information can be input to the control unit 31 by operating the input unit 34.

[0059] The output unit 35 is, for example, a display monitor, a touch panel display, or a speaker. The output unit 35 displays images acquired from the imaging unit 134, displays a screen for operating the combustion control device 3, or outputs sound, according to the control unit 31. In other words, the output unit 35 is configured to notify predetermined information to the outside. Alternatively, the input unit 34 and the output unit 35 may be combined into an input / output unit, and the input / output unit may consist of a touch panel display, a speaker microphone, or the like.

[0060] The unburned material detection model 32a is a trained model that determines the amount of incompletely burned lumps. For the sake of explanation, incompletely burned lumps may be referred to as unburned material. When image data is input to the unburned material detection model 32a, it outputs an evaluation value indicating the amount of unburned material. The unburned material detection model 32a is generated by machine learning, such as deep learning using a neural network such as a CNN (Convolutional Neural Network). The unburned material detection model 32a uses an input / output dataset as training data, where image data labeled to indicate the amount of unburned material is the input parameter, and an evaluation value indicating the amount of unburned material is the output parameter. The image data used as the input parameter during machine learning is, for example, the image data output from the imaging unit 134. When there is no unburned material in the image or it can be ignored, a lower limit label (e.g., 0) is assigned, and when there is unburned material in the image that exceeds a predetermined tolerance range, an upper limit label (e.g., 100) is assigned. During the operation of the waste incinerator 100, the amount of unburned material varies, so the unburned material determination model 32a may output an evaluation value between the upper and lower limits. The range of possible evaluation values ​​may be between 0 and 1, or other ranges.

[0061] By using a pre-trained model that determines the amount of unburned material, it is expected that the accuracy of determining from image data whether control is necessary to burn the unburned material will improve. When an operator determines the presence or absence of unburned material, it is thought that they make a comprehensive judgment by considering not only the size of the bright and dark parts of the flame, but also information such as the shape of the flame and its positional relationship with the grate 104. Since it is difficult to explicitly incorporate all such tacit knowledge as features into the judgment conditions, it is expected that by using the pre-trained model proposed in this invention, which is trained to label the presence or absence of unburned material, it will be possible to mimic the operator's judgment based on tacit knowledge.

[0062] The control unit 31 loads the program stored in the storage unit 32 into the working area of ​​the main memory and executes it, thereby realizing functions that are in line with the objectives of the present invention. In this embodiment, the execution of the program loaded by the control unit 31 realizes the functions of the image acquisition unit 31a, the measurement value acquisition unit 31b, the determination unit 31c, the correction amount calculation unit 31d, the manipulated amount calculation unit 31e, the manipulated amount correction unit 31f, and the operation end control unit 31g.

[0063] The image acquisition unit 31a acquires image data transmitted from the imaging unit 134.

[0064] The measurement value acquisition unit 31b acquires measurement values ​​from the combustion chamber gas temperature sensor 131a, the main flue gas temperature sensor 131b, the furnace outlet gas temperature sensor 131c, the boiler outlet gas temperature sensor 131d, the gas concentration sensor 132, and the exhaust gas flow rate sensor 133.

[0065] The determination unit 31c takes the image data acquired by the image acquisition unit 31a as input parameters and inputs them to the unburned material determination model 32a. The determination unit 31c outputs the output parameters of the unburned material determination model 32a as evaluation values ​​to the correction amount calculation unit 31d.

[0066] If the evaluation value output from the determination unit 31c is greater than or equal to a predetermined threshold, the correction amount calculation unit 31d calculates a correction amount based on the evaluation value and a predetermined control variable correction formula. Specifically, the correction amount calculation unit 31d calculates the following as correction amounts: combustion air correction amount, secondary combustion air correction amount, recirculation gas correction amount, damper opening correction amount, waste supply rate correction amount, and grate feed rate correction amount. If the evaluation value output from the determination unit 31c is less than the threshold, the correction amount calculation unit 31d calculates 0 as the correction amount. The correction amount is calculated for each of the multiple control terminals.

[0067] The control variable calculation unit 31e calculates a reference control variable based on the various measurement values ​​acquired by the measurement value acquisition unit 31b, using input parameters and predetermined control variable relational formulas. The reference control variables are the amount of combustion air, the amount of secondary combustion air, the amount of recirculated gas, the damper opening, the waste supply rate, and the grate feed rate. The control variable relational formula is a formula used to calculate the reference control variable. The reference control variable is a value that serves as the basis for the control variable, calculated based on the design conditions of the incinerator. The reference control variable is calculated for each of the multiple control ends.

[0068] The manipulated variable correction unit 31f corrects the reference manipulated variable based on the correction amount output by the correction amount calculation unit 31d and outputs it as the manipulated variable. If the correction amount output by the correction amount calculation unit 31d is 0, the manipulated variable correction unit 31f outputs the reference manipulated variable as the manipulated variable.

[0069] The operating end control unit 31g controls each operating end based on the operating amount output by the operating amount correction unit 31f. Specifically, the operating end control unit 31g controls the combustion air blower 121 based on the combustion air amount, which is the operating amount output by the operating amount correction unit 31f. The operating end control unit 31g also controls the secondary combustion air blower 123 based on the secondary combustion air amount, which is the operating amount output by the operating amount correction unit 31f. The operating end control unit 31g also controls the recirculation gas blower 125 based on the recirculation gas amount, which is the operating amount output by the operating amount correction unit 31f. Furthermore, the operating end control unit 31g controls the opening degrees of the under-grille combustion air dampers 122a, 122b, and 122c based on the damper opening degree, which is the operating amount output by the operating amount correction unit 31f. Finally, the operating end control unit 31g controls the drive unit of the waste supply device 103 based on the waste supply speed, which is the operating amount output by the operating amount correction unit 31f. Furthermore, the control end control unit 31g controls the grate feed speed, which is the manipulated amount output by the manipulated amount correction unit 31f, to control the drive device of the grate 104.

[0070] Next, the procedure for the processing performed by the control unit 31 will be described. Figure 4 is a flowchart showing the procedure for the manipulated variable calculation process performed by the control unit 31. The manipulated variable calculation process is the process of calculating the manipulated variable at the control terminal. The control unit 31 performs the process shown in Figure 4 at a predetermined period. This period is, for example, several seconds to tens of seconds.

[0071] The control unit 31 acquires image data transmitted from the imaging unit 134 and measurement values ​​from various sensors (S101).

[0072] The control unit 31 calculates a reference control variable for each of the multiple control terminals based on the acquired measurement values ​​and a predetermined control variable relation formula (S102).

[0073] The control unit 31 determines the amount of unburned material (S103). The control unit 31 uses the acquired image data as an input parameter and inputs it to the unburned material determination model 32a. The unburned material determination model 32a then outputs an evaluation value indicating the amount of unburned material.

[0074] The control unit 31 determines whether the evaluation value exceeds a predetermined threshold (S104).

[0075] If the evaluation value is below the threshold (S104: NO), the control unit 31 sets the correction amount to 0 (S106).

[0076] If the evaluation value exceeds the threshold (S104: YES), the control unit 31 calculates the correction amount according to the procedure shown in Figure 5 (S105).

[0077] The control unit 31 corrects the calculated manipulated variable with the calculated correction amount (S107).

[0078] The control unit 31 controls the operating end with the corrected operating amount (S108). After the process in S108, the flow in Figure 4 ends (end).

[0079] Figure 5 is a flowchart showing the procedure for the correction amount calculation process performed by the control unit 31. The correction amount calculation process is the process of calculating the correction amount for the operating end.

[0080] The control unit 31 determines whether the measured value of nitrogen oxide concentration obtained from the gas concentration sensor 132 exceeds a predetermined threshold (S201).

[0081] If the measured nitrogen oxide concentration exceeds a predetermined threshold (S201: YES), the control unit 31 calculates the grate feed speed correction amount, the combustion air correction amount, and the recirculation gas correction amount (S205). Specifically, for the grate feed speed correction amount, the control unit 31 calculates a correction amount to slow down the grate feed speed. Alternatively, the control unit 31 may calculate a correction amount to set the grate feed speed to 0, i.e., a correction amount to stop the grate 104. The control unit 31 also calculates a correction amount to increase the combustion air for the combustion air correction amount. The control unit 31 also calculates a correction amount to increase the recirculation gas for the recirculation gas correction amount. For correction amounts other than the grate feed speed correction amount, combustion air correction amount, and recirculation gas correction amount, the control unit 31 calculates 0 as the correction amount. After processing in S205, the flow in Figure 5 ends (end).

[0082] If the measured nitrogen oxide concentration does not exceed a predetermined threshold (S201:NO), the control unit 31 determines whether the measured exhaust gas flow rate obtained from the exhaust gas flow rate sensor 133 exceeds a predetermined threshold (S202).

[0083] If the measured exhaust gas flow rate exceeds a threshold (S202: YES), the control unit 31 calculates a correction amount for the grate feed speed, a correction amount for the damper opening, and a correction amount for the waste supply speed (S204). Specifically, for the grate feed speed correction amount, the control unit 31 calculates a correction amount that slows down the grate feed speed. Alternatively, the control unit 31 may calculate a correction amount that sets the grate feed speed to 0, i.e., a correction amount that stops the grate 104. The control unit 31 also calculates a correction amount for the damper opening that decreases the opening of the under-grate combustion air damper 122a that supplies combustion air to the wind box 105a, and a correction amount that increases the opening of the under-grate combustion air damper 122b that supplies combustion air to the wind box 105b. The control unit 31 also calculates a correction amount for the waste supply speed correction amount that slows down the supply speed of the waste 50. At this point, the control unit 31 calculates 0 as the correction amount for all correction amounts other than the grate feed speed correction amount, damper opening correction amount, and waste supply speed correction amount. After processing in S204, the flow in Figure 5 ends (end).

[0084] If the measured exhaust gas flow rate obtained from the exhaust gas flow rate sensor 133 does not exceed the threshold (S202: NO), the control unit 31 calculates the grate feed speed correction amount and the combustion air correction amount (S203). Specifically, for the grate feed speed correction amount, the control unit 31 calculates a correction amount that slows down the grate feed speed. Alternatively, the control unit 31 may calculate a correction amount that sets the grate feed speed to 0, i.e., a correction amount that stops the grate 104. The control unit 31 also calculates a correction amount that increases the combustion air for the combustion air correction amount. For correction amounts other than the grate feed speed correction amount and the combustion air correction amount, the control unit 31 calculates 0 as the correction amount. After processing in S203, the flow in Figure 5 ends (end).

[0085] According to the aforementioned calculation of the manipulated amount and the correction amount, for example, if the amount of unburned material exceeds a threshold, the feed speed of the grate 104 slows down, so that the unburned material stays on the grate 104 for a longer time, allowing it to burn. Also, according to the aforementioned calculation of the manipulated amount and the correction amount, if the concentration of nitrogen oxides in the exhaust gas of the flue 11 exceeds a threshold, the amount of combustion air supplied to the combustion chamber 101 increases, and the amount of recirculated gas supplied to the combustion chamber 101 increases, thus suppressing the generation of nitrogen oxides. Furthermore, according to the aforementioned calculation of the manipulated amount and the correction amount, if the flow rate of the exhaust gas of the flue 11 exceeds a threshold, the supply speed of the waste 50 supplied into the combustion chamber 101 slows down, the amount of combustion air supplied to the drying stage decreases, and the amount of combustion air supplied to the combustion stage increases. As a result, the flow rate of the exhaust gas can be suppressed. Furthermore, according to the aforementioned calculation of the manipulated amount and the calculation of the correction amount, the grate feed speed, waste supply speed, damper opening, combustion air volume, and recirculated gas volume are controlled according to the amount of unburned material in the combustion chamber 101. As a result, the temperature inside the combustion chamber 101 can be maintained within a predetermined range, and the waste 52 on the grate can be burned while suppressing the generation of harmful substances.

[0086] [Differentiation] Although embodiments of the present invention have been described above, the present invention can be implemented in various other forms. For example, the present invention may be implemented by modifying the above embodiments as follows. Furthermore, the present invention is also included in configurations that appropriately combine the components of each of the above embodiments and each of the modified forms. Further effects and modifications can be easily derived by those skilled in the art.

[0087] In the embodiment described above, combustion air is supplied to the wind box 105c, but recirculated exhaust gas may also be supplied to the wind box 105c. Figure 6 is a configuration diagram showing a waste incineration facility 1A that supplies exhaust gas as recirculated gas to the wind box 105c. Note that in Figure 6, the same reference numerals are used for components that are the same as those in waste incineration facility 1, and their explanations are omitted. The waste incinerator 100 of waste incineration facility 1A is equipped with a grate recirculation gas blower 127, a grate recirculation gas damper 128a, and a grate recirculation gas supply line 128 for supplying grate recirculation gas from the grate 104 into the combustion chamber 101. The grate recirculation gas is recirculated gas supplied to the region where post-combustion takes place. The grate recirculation gas blower 127 is a blower that sends out grate recirculation gas. The grate recirculation gas damper 128a is a device that adjusts the flow rate of grate recirculation gas. The grate recirculation gas damper 128a is installed in the grate recirculation gas supply line 128. The grate recirculation gas supply line 128 is a pipe through which the grate recirculation gas flows.

[0088] In this configuration, the ash content of the burnt waste 50 is carbonized by the recirculated gas supplied from the wind box 105c. In this configuration, in S205, a correction amount may be calculated to correct the amount of recirculated gas supplied by the recirculated gas blower 127, and the standard operating amount of recirculated gas supplied by the recirculated gas blower 127 may be corrected based on the calculated correction amount.

[0089] In the embodiment described above, a partition 113 is provided in the combustion chamber 101, but a configuration without a partition 113 is also possible. Figure 7 is a diagram showing a waste incineration facility 1B in which a partition 113 is not provided in the combustion chamber 101. Note that the same reference numerals are used for components that are the same as those in waste incineration facilities 1 and 1A, and their descriptions are omitted. In the waste incinerator 100 of waste incineration facility 1B, a partition 113 is not provided, and a recirculation gas inlet 114 is provided at the top of the combustion chamber 101. Recirculation gas is injected into the combustion chamber 101 from these multiple recirculation gas inlets 114.

[0090] In waste incineration facility 1B, which does not have a partition 113, recirculated gas is supplied to the wind box 105c. However, in the configuration without a partition 113, combustion air may be supplied to the wind box 105c. Figure 8 is a diagram showing the configuration of waste incineration facility 1C, in which a partition 113 is not provided in the combustion chamber 101 and combustion air is supplied to the wind box 105c. In the waste incinerator 100 of waste incineration facility 1C, there is no grate-under recirculation gas blower 127 and grate-under recirculation gas damper 128a, and combustion air is supplied to the wind box 105c via the grate-under combustion air damper 122c.

[0091] In the present invention, the control unit 31 may, for example, determine YES in S104 if the evaluation value output by the unburned material determination model 32a exceeds a threshold multiple times in a row.

[0092] In the embodiments described above, the operating ends on which the amount of operation is corrected may be one or more of the operating ends of the grate 104 drive unit, waste supply unit 103, grate recirculation gas blower 127, combustion air blower 121, and grate combustion air dampers 122a and 122b. [Explanation of Symbols]

[0093] 1, 1A, 1B, 1C Waste Incineration Facilities 3. Combustion control device 11 Flue 12 Dust removal equipment 13. Drug supply device 14. Induced draft ventilation fan 15 Chimney 31 Control Unit 31a Image acquisition section 31b Measurement acquisition unit 31c Judgment part 31d Correction amount calculation section 31e Manipulated amount calculation section 31f Operation amount correction section 31g Operating end control unit 32 Storage section 32a Model for determining unburned material 33 Interfaces 34 Input section 35 Output section 50 waste 100 waste incinerators 101 Combustion chamber 101a Furnace wall 102 Waste Inlet 103 Waste supply device 104, 1041~104 n Fire grate 105a, 105b, 105c wind box 106 Ash fall hole 107 Furnace outlet 109 Boiler 109a heat exchanger 109b Steam Drum 111 Waste Supply Department 112 Step wall 113 partitions 114 Recirculation gas inlet 115 Secondary combustion air inlet 121 Combustion air blower 122 Combustion air supply line 122a, 122b, 122c Air damper for combustion below the grate 123 Secondary combustion air blower 124 Secondary combustion air supply line 124a Secondary combustion air damper 125 Recirculating Gas Blower 126 Recirculating gas supply line 126a Recirculating Gas Damper 127 Recirculating gas blower under the grate 128 Recirculating gas supply line below the grate 128a Recirculating gas damper below the grate 131a Combustion chamber gas temperature sensor 131b Main flue gas temperature sensor 131c Furnace Outlet Gas Temperature Sensor 131d Boiler outlet gas temperature sensor 132 Gas concentration sensor 133 Exhaust gas flow sensor 134 Imaging Unit

Claims

1. A combustion control device for controlling an incinerator equipped with a grate for moving waste, An image acquisition unit that acquires image data of the waste on the aforementioned grate, A measurement value acquisition unit that acquires measurement values ​​from a sensor that measures exhaust gas generated by the combustion of the waste in the incinerator, A determination unit that outputs the amount of unburned material in the incinerator as an evaluation value based on the image data, An operating variable calculation unit that calculates a reference operating variable based on the measured values, An operating variable correction unit corrects the reference operating variable based on the evaluation value and outputs it as an operating variable, An operating end control unit that controls the operating end of the incinerator based on the aforementioned operating amount, A combustion control device equipped with the following features.

2. The combustion control device according to claim 1, wherein the range of the evaluation value is defined as the lower limit of the evaluation value when a predetermined amount of unburned material is present on the grate, and the upper limit of the evaluation value when another predetermined amount greater than or equal to the predetermined amount of unburned material is present on the grate.

3. The combustion control device according to claim 1, wherein the operating end is one of the following: a drive device for the grate, a waste supply device for supplying the waste to the grate, a recirculating gas blower for supplying exhaust gas to the incinerator, an air blower for supplying air to the incinerator, or a damper provided in each of a plurality of flow paths for supplying the air to the grate, for adjusting the flow rate of the air in the said flow path.

4. The combustion control device according to claim 3, wherein if the evaluation value exceeds a predetermined threshold, a correction amount is calculated, and the reference operating amount is corrected by the calculated correction amount.

5. The combustion control device according to claim 3, wherein if the evaluation value is less than a predetermined threshold, the correction amount is set to 0, and the reference operating amount is corrected by the set correction amount.

6. The combustion control device according to claim 4, wherein if the concentration of nitrogen oxides in the exhaust gas measured by the sensor exceeds a predetermined threshold, the device calculates a correction amount for the grate drive unit, a correction amount for the air blower, and a correction amount for the recirculating gas blower.

7. The combustion control device according to claim 4, wherein if the concentration of nitrogen oxides in the exhaust gas measured by the sensor is below a predetermined threshold, and the flow rate of the exhaust gas measured by the sensor exceeds a predetermined threshold, the correction amount for the grate drive device, the correction amount for the damper, and the correction amount for the waste supply device are calculated.

8. The combustion control device according to claim 4, wherein if the concentration of nitrogen oxides in the exhaust gas measured by the sensor is below a predetermined threshold, and the flow rate of the exhaust gas measured by the sensor is below a predetermined threshold, the correction amount for the grate drive device and the correction amount for the air blower are calculated.

9. A combustion control method for controlling an incinerator equipped with a grate for moving waste, Image data of the waste on the aforementioned grate is acquired, A sensor that measures exhaust gas generated by the combustion of the waste in the incinerator acquires measurement values. Based on the aforementioned image data, the amount of unburned material in the incinerator is output as an evaluation value. Based on the above measured values, the standard manipulated variable is calculated. Based on the evaluation value, the reference manipulated variable is corrected and output as the manipulated variable. The operating end of the incinerator is controlled based on the aforementioned operating amount. Combustion control method.

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