Sintering control device, sewage treatment equipment, sintering control method, and program

Abstract

This method predicts the degree of sintering based on the combination of dewatered sludge composition and incineration temperature. [Solution] The system includes an acquisition unit that acquires information indicating the composition of the dewatered sludge to be incinerated and the incineration temperature for incinerating the dewatered sludge; a prediction unit that predicts the degree of sintering when the dewatered sludge to be incinerated is incinerated at the incineration temperature, based on the liquid phase ratio predicted based on the combination of composition and temperature acquired by the acquisition unit and table information that associates the degree of sintering with the combination of composition and incineration temperature; and an output unit that outputs the degree of sintering predicted by the prediction unit.

Description

Technical Field

[0001] The present invention relates to a sintering control device, a sewage treatment facility, a sintering control method, and a program.

Background Art

[0002] Conventionally, in the operation of an incinerator, a phenomenon in which the incinerator becomes blocked has occurred. For example, in a fluidized incinerator, when exhaust gas and incineration ash generated during incineration flow into equipment such as an air preheater while remaining at a high temperature, the molten incineration ash adheres to the flue, preventing the flow of exhaust gas, or clogging occurs, for example, in the header portion of the air preheater, which may cause the incinerator to become blocked. In that case, it becomes difficult to continue stable continuous operation, and there is a possibility that problems such as thermal damage to the equipment may occur.

[0003] Therefore, attempts have been made to evaluate the risk of blockage of the incinerator and suppress the blockage. For example, when incinerating sewage sludge, depending on the balance of the abundance of phosphorus, a specific substance contained in the sewage sludge introduced into the incinerator, and metals, a phosphorus compound having a melting point lower than the combustion temperature of the incinerator is formed. It is presumed that the incinerator becomes blocked when the incineration ash containing such a low-melting-point phosphorus compound melts and adheres to the flue. Patent Document 1 discloses a blockage suppression index that is the ratio of the amount of phosphorus that can bind a plurality of high-melting-point metal elements capable of forming a phosphorus compound having a melting point higher than the combustion temperature of the incinerator to the amount of phosphorus contained in the suspected incineration ash, and a technique for evaluating the risk of blockage of the incinerator based on the correlation between the RGB value as color data of the incineration ash and the blockage suppression index.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, conventional evaluation formulas, such as the blockage suppression index mentioned above, had room for improvement. For example, in recent years, in consideration of global warming, there has been a demand to reduce the amount of nitrous oxide contained in the exhaust gas produced during incineration. For example, in fluidized bed incinerators, exhaust gas is produced during incineration, and this exhaust gas contains nitrous oxide (N2O), a type of greenhouse gas. In order to reduce the amount of nitrous oxide emitted, fluidized bed incinerators are now operated at higher temperatures. However, conventional evaluation formulas assume that the incineration temperature is fixed, making it difficult to evaluate the relationship between the incineration temperature and the degree to which the incinerated ash melts. Furthermore, in recent years, the concentration of phosphorus in dewatered sludge has been increasing, and as the phosphorus concentration increases, the melting point of the incinerated ash tends to decrease. However, conventional evaluation formulas were derived based on actual results and adhesion tests, making it difficult to adapt to changes in the phosphorus concentration in dewatered sludge.

[0006] In view of the above-mentioned problems, the object of the present invention is to provide a sintering control device, a sewage treatment facility, a sintering control method, and a program that can predict the degree of sintering according to the combination of the composition of dewatered sludge and the incineration temperature. [Means for solving the problem]

[0007] To solve the above-mentioned problems, one aspect of the present invention is a sintering control device comprising: an acquisition unit that acquires information indicating the composition of the dewatered sludge to be incinerated and the incineration temperature for incinerating the dewatered sludge; a prediction unit that predicts the degree of sintering when the dewatered sludge to be incinerated is incinerated at the incineration temperature, based on the liquid phase ratio predicted based on the combination of composition and temperature acquired by the acquisition unit and table information relating the degree of sintering to the combination of composition and incineration temperature; and an output unit that outputs the degree of sintering predicted by the prediction unit.

[0008] To solve the above-mentioned problems, one aspect of the present invention is a sewage treatment facility equipped with the sintering control device described above.

[0009] One aspect of the present invention is a sintering control method performed by a computer which is a sintering control device, wherein an acquisition unit acquires information indicating the composition of the dewatered sludge to be incinerated and the incineration temperature for incinerating the dewatered sludge; a prediction unit predicts the degree of sintering when the dewatered sludge to be incinerated is incinerated at the incineration temperature, based on the liquid phase ratio predicted based on the combination of composition and temperature acquired by the acquisition unit and table information relating the degree of sintering to the combination of composition and incineration temperature; and an output unit outputs the degree of sintering predicted by the prediction unit.

[0010] One aspect of the present invention is a program for causing a computer, which is a sintering control device, to function as an acquisition means for acquiring information indicating the composition of the dewatered sludge to be incinerated and the incineration temperature for incinerating the dewatered sludge; a prediction means for predicting the degree of sintering when the dewatered sludge to be incinerated is incinerated at the incineration temperature, based on the liquid phase ratio predicted based on the combination of composition and temperature acquired, and table information relating the degree of sintering to the combination of composition and incineration temperature; and an output means for outputting the predicted degree of sintering. [Effects of the Invention]

[0011] According to the present invention, the degree of sintering can be predicted according to the combination of the composition of dewatered sludge and the incineration temperature. [Brief explanation of the drawing]

[0012] [Figure 1] This figure shows the system configuration of the sintering control system 400 according to the embodiment. [Figure 2] This diagram illustrates the flow of wastewater treatment performed by the sewage treatment facility SB. [Figure 3] This diagram illustrates the configuration of the sewage treatment performed by the sewage treatment facility SB. [Figure 4] This is a flowchart showing the processing flow performed by the sintering control device 100. [Figure 5] This figure shows an example of liquid phase information. [Figure 6] This figure shows an example of visualizing liquid phase information. [Figure 7] This figure shows an example of information stored in the table information storage unit 106. [Figure 8] This is a diagram illustrating the processes performed by the sintering control device 100. [Figure 9] This is a flowchart showing the processing flow performed by the sintering control device 100. [Figure 10] This figure shows the system configuration of a sintering control system 400 according to a modified embodiment. [Modes for carrying out the invention]

[0013] The following describes a sintering control device 100 and a sewage treatment facility SB according to one embodiment of the present invention with reference to the drawings.

[0014] Figure 1 shows the system configuration of the sintering control system 400 according to the embodiment. The sintering control system 400 includes, for example, a sewage treatment facility SB, a sintering control device 100, a computing device 200, and a learning device 300.

[0015] The sewage treatment facility SB is a facility that treats sewage. In the sewage treatment facility SB, the dewatered sludge, which is obtained by dewatering the sludge contained in the sewage, is incinerated. During the incineration of dewatered sludge, the incinerated ash may adhere to and accumulate in the flue and air preheater at the outlet of the fluidized bed incinerator. This is thought to be because at least a portion of the incinerated ash melts and becomes sticky inside the fluidized bed incinerator, and this sticky ash adheres to the exhaust gas flow path walls at the outlet of the fluidized bed incinerator, and the ash particles then stick together and accumulate. In this specification, the cooling and solidification of the melted and sticky incinerated ash may be referred to as "sintering." In addition, the degree to which the incinerated ash is sintered during the incineration of dewatered sludge may be referred to as the "degree of sintering."

[0016] FIG. 2 is a diagram for explaining the flow of sewage treatment performed by the sewage treatment facility SB. As shown in FIG. 2, the overall sewage treatment method performed by the sewage treatment facility SB includes a water treatment step 1, a sludge treatment step 3, a sludge incineration step 5, a sintering control step 2, a sampling and analysis step 7, and a base substance addition step 8. A phosphorus recovery step may be provided after the sludge incineration step 5.

[0017] The water treatment step 1 is a treatment step for purifying sewage and separating and removing sludge from the sewage. The sludge treatment step 3 is a treatment step for concentrating and dewatering the sludge separated and removed in the water treatment step 1 to obtain dewatered sludge. The sludge incineration step 5 is a step for incinerating the dewatered sludge in an incinerator. In this embodiment, the case of using a fluidized incinerator as the incinerator will be described as an example, but any incinerator, such as a stoker-type incinerator, may be used. When a phosphorus recovery step is provided after the sludge incineration step 5, in the phosphorus recovery step, the phosphorus component in the incineration ash is recovered. The recovered phosphorus component can be used for fertilizers and the like.

[0018] The sampling and analysis step 7, the base substance addition step 8, and the sintering control step 2 are steps for adjusting the composition of the dewatered sludge supplied to the incinerator. By adjusting the composition of the dewatered sludge, the occurrence of sintering can be suppressed. Specifically, by increasing in advance the amount of the base substance with respect to the phosphorus (phosphoric acid) contained in the sludge incinerated in the fluidized incinerator, the generation of a phosphorus compound having a melting point lower than the incineration temperature (for example, the temperature of the freeboard, the temperature of the high-temperature part in the incinerator) is suppressed. Thereby, it is considered that the adhesion of the sintered ash particles is increased due to the melting of the phosphorus compound having a low melting point, making it easier to adhere to the flue and the like, and also making it easier for the sintered ash particles to bind to each other, suppressing the progress of deposition.

[0019] The term "basic substance" here refers specifically to basic substances containing ions of Na (sodium), K (potassium), Ca (calcium), Mg (magnesium), Al (aluminum), Fe (iron), and other ions such as Cu (copper), Zn (zinc), and Ba (barium), for example, K2O, Na2O, CaO, MgO, Al2O3, and Fe2O3, or in addition to these, CuO, ZnO, BaO, etc.

[0020] Figure 3 is a diagram illustrating the configuration of the sewage treatment performed by the sewage treatment facility SB. In the example in Figure 3, in water treatment process 1, the inflowing sewage 10 from the outside first flows into the grit tank 11, where large debris and sediment are removed, and then flows into the primary sedimentation tank 12, where it is physically separated into primary sludge (corresponding to the raw sludge described later) and supernatant water. The supernatant water (wastewater) then flows into the reaction tank 13, where it is purified using the activated sludge method. That is, activated sludge containing microorganisms is mixed with the wastewater by aeration using air from the blower 14, and organic matter in the wastewater is decomposed. Furthermore, the wastewater mixed with the activated sludge from the reaction tank 13 flows into the final sedimentation tank 15, where the activated sludge and wastewater are physically separated, the activated sludge is returned to the reaction tank, and a portion of it is withdrawn as excess sludge. The supernatant water from the final sedimentation tank 15 is then discharged as purified water 16, or it is discharged after undergoing further advanced treatment.

[0021] In sludge treatment step 3, the primary sedimentation sludge (raw sludge) withdrawn from the primary sedimentation tank 12 is settled in a gravity thickening tank 31, for example, as a raw sludge thickening means. The settled material (concentrated raw sludge) in the gravity thickening tank 31 is then sent to a mixing point 33, described later, via a raw sludge receiving tank 32. Meanwhile, a portion of the activated sludge settled in the final sedimentation tank 15 is withdrawn from the final sedimentation tank 15 as excess sludge, and sent to a centrifugal thickener 35, for example, as an excess sludge thickening means, via an excess sludge storage tank 34. The concentrated excess sludge separated from water in the centrifugal thickener 35 is then sent to the mixing point 33. At the mixing point 33, the concentrated raw sludge and the concentrated excess sludge are mixed, and the mixed concentrated sludge is then supplied to a dewatering machine 38, such as a belt press dewatering machine, via a mixed sludge storage tank 36 and a coagulation mixing tank 37, for example. The sludge is then dewatered by the dewatering machine 38 and, in a somewhat solidified state, such as a cake-like form, is sent as dewatered sludge to the next sludge incineration process 5 by a supply device 39 such as a pressure pump or conveyor belt.

[0022] The sludge incineration process 5 is equipped with a fluidized bed incinerator 51 that forms a fluidized bed by blowing combustion air into a fluidized medium such as sand, and heats and incinerates dewatered sludge in the fluidized bed. This fluidized bed incinerator 51 is configured so that high-temperature air (combustion air) heated by an air preheater 53 is blown in from the bottom (below the fluidized bed) via a blower 52. Then, dewatered sludge supplied from the supply device 39 of the sludge treatment process 3 is supplied into the fluidized bed incinerator 51 by a supply machine 55 such as a quantitative feeder, input conveyor, and input pump, and incinerated. At this time, incineration ash (incineration residue; dust) is discharged from the top of the fluidized bed incinerator 51 along with the exhaust gas and is guided to the air preheater 53 through a flue 56. The air preheater 53 preheats the air from the blower 52 by exchanging heat between the air from the blower 52 and the exhaust gas from the fluidized bed incinerator 51. Meanwhile, the exhaust gas from the fluidized bed incinerator 51 that has passed through the air preheater 53 is led to a dust collector 57 where dust (incinerated ash) is removed, and then, if necessary, released into the atmosphere via a cooling absorption tower or other means (not shown). The incinerated ash collected by the dust collector 57 is also supplied to a phosphorus recovery facility 58 as needed.

[0023] In the sampling and analysis step 7, between the sludge treatment step 3 and the sludge incineration step 5, the dewatered sludge is sampled before being supplied to the fluidized bed incinerator, and the composition of the sampled dewatered sludge is analyzed, specifically the amounts of Na, Cl, K, Ca, Mg, Al, Mn, Ti, Si, S, Fe, P (phosphorus), or in addition to these, the amounts of Cu, Zn, and Ba. The sampling and analysis step 7 is equipped with a sampling means 71 for sampling an analytical sample from the dewatered sludge, an analytical device 72 for analyzing the components of the sampled sample, and a calculation device 73 for calculating an evaluation index value X of the composition of the dewatered sludge from the amounts of each component analyzed by the analytical device 72.

[0024] The evaluation index value X can be any index that can evaluate the degree of sintering during the incineration of dewatered sludge from the perspective of the composition of the dewatered sludge. For example, an index showing the ratio of phosphorus components to basic substance components (Ca, Fe, etc.) contained in the dewatered sludge can be used. More specifically, as the evaluation index value X, for example, any of the evaluation index values ​​X1 to X2 shown in equations (1) to (2) below can be used. The unit of each component (substance) amount in equations (1) to (2) is [mol]. X1={Na+K+(Ca×2)+(Mg×2)+(Al×3)+(Fe×3)} / (P×3)…(1) formula X2={Na+K+(Ca×2)+(Mg×2)+(Al×3)+(Fe×3)+Cu+Zn+(Ba×2)} / (P×3)…Equation (2)

[0025] In the basic substance addition step 8, basic substances are added to the sludge if it is determined that increasing the amount of basic substances in the dewatered sludge is desirable from the viewpoint of suppressing sintering. Specifically, in the composition of the dewatered sludge, if the content of each component (Na, K, Ca, Mg, Al, Fe, or other components such as Cu, Zn, Ba) is low relative to the content of P, one or more basic substances selected from among Al2O3, Fe2O3, CaO, CaCO3, MgO, etc. are added to the sludge.

[0026] The form of the basic substance when it is added is not particularly limited; it may be added in liquid form, such as a slurry or aqueous solution suspended in a dispersion medium such as water, or in powder form. However, except when it is added into the furnace in a fluidized bed incinerator, it is preferable to add it in liquid form so that it can be easily added to the sludge. The location where the basic substance is added is not particularly limited; it can be added at any stage from the start of sewage treatment until the dewatered sludge is supplied to the fluidized bed incinerator. In other words, it can be added at one or more locations, such as any tank between the water treatment process and the sludge treatment process, in the middle of the sludge piping, along the transport route of dewatered sludge (dewatered sludge cake) from the sludge treatment process to the fluidized bed incinerator, or in the fluidized bed incinerator itself, by selecting a location where the basic substance can be retained in the sludge as effectively as possible.

[0027] Figure 3 illustrates the locations where the base substance is added (addition points Q1 to Q8). However, addition points Q1 to Q8 merely indicate suitable locations for adding the base substance. In other words, it is not necessary to add the base substance at all of these addition points Q1 to Q8; as will be explained later, it is sufficient to select one or more addition points from these to add the base substance. To put it another way, in terms of equipment, it is sufficient to have a device for adding the base substance (addition device) at one or more of these addition points Q1 to Q8.

[0028] Addition point Q1 is the point in the sludge treatment process 3 where a basic substance is added to the gravity thickening tank 31. Adding a basic substance such as polyferric iron (polyferric sulfate) to the gravity thickening tank 31 has been done conventionally for the purpose of deodorization. When adding a basic substance to suppress sintering, it is sufficient to add the amount of basic substance added to the gravity thickening tank 31 for the purpose of deodorization, in addition to the amount of basic substance added for sintering suppression. Addition point Q2 is the point in the sludge treatment process 3 where a basic substance is added to the raw sludge receiving tank 32. Adding a basic substance such as polyferrous iron to the raw sludge receiving tank 32 has been done conventionally for the purpose of deodorization. When adding a basic substance to suppress sintering, the amount of basic substance added to the raw sludge receiving tank 32 for deodorization should be increased to include the amount of basic substance added for sintering suppression. Addition point Q3 is the point in the water treatment process 1 where a basic substance is added to the reaction tank 13. Adding a basic substance such as PAC (polyaluminum chloride) to the reaction tank 13 is a common practice for improving phosphorus recovery efficiency. When adding a basic substance to suppress sintering, the amount of basic substance added to the raw sludge receiving tank 32 for deodorization purposes should be increased to include the amount of basic substance added for sintering suppression. Addition point Q4 is the point in sludge treatment process 3 where a basic substance is added to the excess sludge storage tank 34. Addition point Q5 is the point in sludge treatment process 3 where a basic substance is added to the mixed sludge storage tank 36. Addition point Q6 is the point in sludge treatment process 3 where a basic substance is added to the coagulation and mixing tank 37. Addition point Q7 is the point in sludge treatment process 3 where a basic substance is added to the dewatered sludge in the feeding device 39. Addition point Q8 is the point in sludge incineration process 5 where dewatered sludge is supplied to the fluidized bed incinerator 51, and at the same time, a basic substance is blown into the fluidized bed incinerator 51. Blowing powder of a basic substance containing Ca ions, such as slaked lime, into the fluidized bed incinerator 51 has been done conventionally for the purpose of reducing the sulfur component in the exhaust gas. When adding a basic substance to suppress sintering, it is sufficient to add a basic substance for suppressing sintering in addition to the amount of basic substance added to the fluidized bed incinerator for the purpose of reducing the sulfur component.

[0029] Conventionally, in the base substance addition step 8, a base substance was added so that the evaluation index value X would be equal to or greater than a threshold (for example, 1.0 or 1.05). However, conventional methods assumed that the incineration temperature was within a certain range, for example, between 840 and 900°C, preferably between 850 and 900°C, and set a uniform value (e.g., 1.0 or 1.05) independent of the incineration temperature as the threshold for the evaluation index value X. Therefore, it was difficult to apply this method to incineration at higher temperatures. Furthermore, the threshold for the evaluation index value X was derived based on actual data such as the degree of adhesion to the flue and the flow state, or the results of adhesion tests. This made it difficult to accommodate changes in the composition of dewatered sludge (e.g., an increase in phosphorus content) or changes in the incineration temperature (e.g., higher-temperature incineration operations to mitigate global warming).

[0030] As a countermeasure, this embodiment makes it possible to predict the degree of sintering according to the combination of the composition of dewatered sludge and the incineration temperature. This makes it possible to accurately predict the possibility of sintered ash adhering to and clogging the incinerator, even when incineration is performed at temperatures for which there is insufficient experience, or when dewatered sludge containing a higher concentration of phosphorus than conventional methods is incinerated.

[0031] Specifically, in this embodiment, as a mechanism for controlling the degree of sintering in the incineration process of dewatered sludge, a sintering control device 100, a computing device 200, and a learning device 300 are provided in addition to the sewage treatment equipment SB, as shown in Figure 1.

[0032] As mentioned above, sintering occurs when molten incinerated ash adheres to flues and other structures. Therefore, if the incinerated ash does not melt, or if the proportion of melting is small, sintering is less likely to occur. Based on this property, it was found that the liquid phase ratio of the dewatered sludge correlates with the degree of sintering of the incinerated ash in the dewatered sludge. Here, the liquid phase fraction is the proportion of liquid in a substance. The liquid phase fraction can be calculated, for example, using software that predicts the thermodynamic equilibrium state of a substance containing multiple components (thermodynamic equilibrium calculation software). Therefore, in this embodiment, the liquid phase ratio is predicted when the composition and temperature of the dewatered sludge are changed, and this liquid phase ratio can be used as an indicator for predicting the degree of sintering.

[0033] The computing device 200 is a computer that calculates the liquid phase ratio. The computing device 200 has a liquid phase ratio calculation unit 201. The liquid phase ratio calculation unit 201 calculates the liquid phase ratio by executing thermodynamic equilibrium calculation software. Thermodynamic equilibrium calculation software is software that predicts the thermodynamic equilibrium state of a multi-component substance, which is a substance having multiple components. The memory unit (not shown) of the computing device 200 stores the thermodynamic equilibrium calculation software. The functionality of the liquid phase ratio calculation unit 201 is realized when a hardware processor such as a CPU (Central Processing Unit) provided in the computing device 200 executes the thermodynamic equilibrium calculation software program stored in the memory unit.

[0034] The learning device 300 is a computer that trains a learning model (for example, a regression model) with training data. The learning device 300 has a regression model 301. The regression model 301 is a model that predicts the liquid phase fraction (liquid phase fraction prediction model) by learning training data according to the control of the sintering control device 100. The regression model 301 is trained to predict the liquid phase fraction according to the input composition and temperature by learning training data that associates composition, temperature, and liquid phase fraction. The process by which the sintering control device 100 trains the regression model 301 will be explained in detail later.

[0035] The sintering control device 100 is a computer that controls the degree of sintering in the incineration process of dewatered sludge. A personal computer (PC), server device, or cloud computer can be used as the sintering control device 100.

[0036] As shown in Figure 1, the sintering control device 100 includes an acquisition unit 101, a sintering degree prediction unit 102, an additive amount calculation unit 103, an output unit 104, a liquid phase fraction prediction model storage unit 105, a table information storage unit 106, a learning data generation unit 107, a prediction model generation unit 108, and a learning data storage unit 109.

[0037] First, the process by which the sintering control device 100 trains the regression model 301 will be described. In this embodiment, the learning data generation unit 107 generates learning data, and the prediction model generation unit 108 trains the regression model 301 with the learning data to generate a prediction model (liquid phase fraction prediction model). The learning data generation unit 107 generates learning data to be trained on the regression model 301 of the learning device 300. In this embodiment, the liquid phase fraction corresponding to the combination of composition and temperature calculated by the liquid phase fraction calculation unit 201 of the computing device 200 is used as learning data to be trained on the regression model 301 of the learning device 300. First, the learning data generation unit 107 sets numerical ranges for composition and temperature, respectively, as the range for predicting the liquidus fraction. For example, the sintering control device 100 sets the range of values ​​D1 to D5 as the numerical range for composition and the range of 600[°C] to 1200[°C] as the numerical range for temperature, as the range for predicting the liquidus fraction. Then, the sintering control device 100 extracts several representative points from the numerical ranges. For example, from the numerical range of values ​​D1 to D5, which are the evaluation index values ​​for composition, it extracts values ​​D1, D2, D3, D4, and D5 as representative points. Also, from the numerical range of temperature 600[°C] to 1200[°C], it extracts 600[°C], 750[°C], 900[°C], 1050[°C], and 1200[°C] as representative points. Next, the learning data generation unit 107 generates combinations (grid points) of representative points for composition and temperature. The sintering control device 100 notifies the computing device 200 of the coordinates of the grid points as combinations of composition and temperature, and requests that it calculate the liquid phase fraction corresponding to the coordinates of the notified grid points. In response to the request from the sintering control device 100, the computing device 200 calculates the liquid phase fraction using thermodynamic equilibrium calculation software and notifies the sintering control device 100 of the calculated liquid phase fraction. The sintering control device 100 stores the liquid phase fraction notified by the computing device 200 in the learning data storage unit 109. The sintering control device 100 causes the computing device 200 to calculate the liquid phase fraction corresponding to each of the possible combinations of representative points for composition and temperature, and stores the liquid phase fraction calculated by the computing device 200 in the learning data storage unit 109.

[0038] The prediction model generation unit 108 generates a liquid phase ratio prediction model, which is a prediction model that predicts the liquid phase ratio according to the combination of composition and temperature. The prediction model generation unit 108 notifies the learning device 300 of the learning data and requests that the regression model 301 be trained with the notified learning data. The learning data notified here is data that associates the liquid phase ratio calculated by the computing device 200 with the coordinates of the grid points (combination of composition and temperature), and is learning data stored in the learning data storage unit 109. The learning device 300 trains the regression model 301 with the learning data in response to the request from the prediction model generation unit 108.

[0039] Here, the regression model 301 can be any regression model, as long as it is a model that predicts at least a numerical value. For example, generalized additive models (GAMs) and generalized linear models (GLMs) can be used as regression model 301. Multivariate models such as Gaussian regression models, SVMs (Support Vector Machines), random forests, and decision trees may also be used as regression model 301. Furthermore, models using deep learning or neural networks may also be used as regression model 301. Furthermore, it is desirable to select a regression model 301 that can ensure the desired prediction accuracy with as little training data as possible. Among the arbitrary regression models mentioned above, some highly flexible regression models such as random forests exhibited overfitting, where prediction accuracy improved on training data but decreased on empirical data. This is thought to be due to a decrease in prediction accuracy for inputs (combinations of composition and temperature) that were outside the range of data that had not been trained, caused by the small amount of training data. From this perspective, it is desirable to use a regression model that can interpolate between different training data even when using a small amount of training data. In particular, it is desirable to use a regression model 301 that predicts the liquid phase fraction, which is the output, according to the combination of composition and temperature, which is the input, using a continuous function; a so-called white-box (glass-box) model. Since the prediction model is a function that can be expressed by a mathematical formula with composition and temperature as variables, it is also possible to calculate the degree to which each basic substance included in the composition contributes to the liquid phase fraction (contribution). Furthermore, in the case of regression models represented by complex combinations of nodes and edges, such as deep learning and neural networks, where weight coefficients and bias values ​​are set for each edge, a huge amount of computation is required to predict the predicted values, resulting in a high processing load. In contrast, when the prediction model is represented by a relatively simple function such as a linear or quadratic function, the number of computations required to predict the predicted values ​​can be reduced. Therefore, the computational load can be reduced compared to using thermodynamic equilibrium calculation software or pre-trained models such as deep learning and neural networks. In this embodiment, it is desirable to use a regression model 301 that predicts the liquid phase fraction, which is the output, according to the combination of composition and temperature, which is the input, using a function with continuity. Specifically, a generalized additive model (GAM), a generalized linear model (GLM), etc., is preferred. Furthermore, when generating training data, the representative points extracted from the respective numerical ranges of composition and temperature may be arbitrarily selected within the numerical range. However, from the perspective of ensuring the desired prediction accuracy with as little training data as possible, it is desirable that the points be extracted without bias between the upper and lower limits of the numerical range.

[0040] The learning device 300 notifies the sintering control device 100 of information necessary for constructing a regression model 301 that has learned from the learning data (for example, information indicating mathematical formulas corresponding to the regression model). The prediction model generation unit 108 stores the information notified by the learning device 300 in the liquid phase rate prediction model storage unit 105 as information for constructing a liquid phase rate prediction model.

[0041] Here, we will explain the process by which the sintering control device 100 generates a liquid phase fraction prediction model using Figure 4. Figure 4 is a flowchart showing the flow of the process performed by the sintering control device 100 in this embodiment. As shown in Figure 4, in the process of generating a liquid phase fraction prediction model, the learning data generation unit 107 of the sintering control device 100 sets a numerical range for the incineration temperature for incinerating the dewatered sludge to be incinerated (step S101). The learning data generation unit 107 sets a numerical range for evaluation index values ​​of the composition that the dewatered sludge to be incinerated can take (step S102). The learning data generation unit 107 generates multiple grid points by combining representative points of temperature and index values ​​(step S103). The learning data generation unit 107 calculates the liquid phase fraction of the grid points using a thermodynamic equilibrium calculation method, i.e., the liquid phase fraction calculation unit 201 (step S104). The learning data generation unit 107 stores the liquid phase fraction of the grid points as learning data in the learning data storage unit 109 (step S105). The prediction model generation unit 108 of the sintering control device 100 generates a liquid phase fraction prediction model by having the regression model 301 learn from the learning data stored in the learning data storage unit 109 (step S106). The prediction model generation unit 108 stores the information necessary to construct the generated liquid phase fraction prediction model in the liquid phase fraction prediction model storage unit 105.

[0042] Next, the process by which the sintering control device 100 predicts the degree of sintering will be described. In this embodiment, a series of processes for predicting the degree of sintering are performed using the acquisition unit 101, the degree of sintering prediction unit 102, the additive amount calculation unit 103, and the output unit 104.

[0043] The acquisition unit 101 acquires various types of information. For example, the acquisition unit 101 acquires information indicating the composition of the dewatered sludge to be incinerated. As information indicating the composition of the dewatered sludge to be incinerated, a composition evaluation index value X can be used. In this case, the acquisition unit 101 acquires the evaluation index value X calculated by the calculation device 73 in the sampling and analysis process 7 of the sewage treatment facility SB. For example, the calculation device 73 calculates the evaluation index value X as information indicating the composition of the dewatered sludge and transmits the calculated evaluation index value X to the sintering control device 100. The sintering control device 100 receives the evaluation index value X notified from the calculation device 73 and outputs the received evaluation index value X to the acquisition unit 101. As a result, the acquisition unit 101 acquires the evaluation index value X. Furthermore, the acquisition unit 101 acquires the incineration temperature for burning the dewatered sludge (the temperature of the freeboard in the fluidized bed incinerator). This incineration temperature may be a value that has been set and stored in advance, a value that has been input by the user, or a value that has been actually measured in the fluidized bed incinerator. Alternatively, if the incineration temperature is stored in advance in the storage unit (not shown) of the sintering control device 100, the acquisition unit 101 may read the incineration temperature from the storage unit and acquire it.

[0044] The sintering degree prediction unit 102 predicts the degree of sintering when the dewatered sludge to be incinerated is incinerated at the incineration temperature. First, the sintering degree prediction unit 102 predicts the liquidus fraction according to the combination of composition and temperature acquired by the acquisition unit 101. The sintering degree prediction unit 102 uses a liquidus fraction prediction model to predict the liquidus fraction according to the combination of composition and temperature. The sintering degree prediction unit 102 reads information for constructing the liquidus fraction prediction model from the liquidus fraction prediction model storage unit 105 and constructs the liquidus fraction prediction model using the read information. The sintering degree prediction unit 102 uses the constructed liquidus fraction prediction model to predict the liquidus fraction corresponding to the combination of composition and temperature acquired by the acquisition unit 101.

[0045] The sintering degree prediction unit 102 may also obtain the liquidus ratio by having the liquidus ratio calculation unit 201 calculate the liquidus ratio according to the combination of composition and temperature. Alternatively, if the learning data storage unit 109 stores the liquidus ratio according to the combination of composition and temperature obtained by the acquisition unit 101, the sintering degree prediction unit 102 may obtain the liquidus ratio by reading the liquidus ratio corresponding to the combination of composition and temperature from the learning data storage unit 109.

[0046] Figure 5 shows an example of liquid phase information. Liquid phase information is information indicating the liquid phase ratio corresponding to the combination of composition and temperature predicted by the sintering degree prediction unit 102 using the liquid phase ratio prediction model. As shown in this figure, the liquid phase information is information that associates the composition evaluation index value, temperature, and liquid phase ratio with the dewatered sludge of the material to be incinerated. The composition evaluation index value is information indicating the composition of the dewatered sludge to be incinerated, and for example, the evaluation index value X described above can be used. The temperature is information indicating the incineration temperature of the material (in this case, dewatered sludge having the composition corresponding to the evaluation index value). The liquid phase ratio is information indicating the liquid phase ratio when the material (in this case, dewatered sludge having the composition corresponding to the evaluation index value) is in a thermodynamic equilibrium state at a given temperature. This figure shows that the liquid phase ratio tends to decrease as the evaluation index value X changes from value D1 to D5. Here, as the value changes from D1 to D5, the value of the evaluation index X increases, that is, the ratio of the basic substance component to the phosphorus component increases. For example, when the evaluation index value X is value D1, the liquid phase ratio at a temperature of 900°C is shown to be 65%. When the evaluation index value X is value D2, the liquid phase ratio at a temperature of 900°C is shown to be 60%. When the evaluation index value X is value D4, the liquid phase ratio at a temperature of 900°C is shown to be 20%. Thus, Figure 5 shows that the liquid phase ratio tends to decrease as the ratio of the basic substance component to the phosphorus component increases.

[0047] Figure 6 shows an example of visualizing liquid phase information by plotting it on a three-dimensional graph. In Figure 6, the x-axis represents the evaluation index value X, which indicates the composition of dewatered sludge. The y-axis represents temperature. The z-axis represents the liquid phase ratio. The xyz relationship corresponding to a temperature of 900 [°C] on the y-axis of this figure corresponds to the example of liquid phase information shown in Figure 5. As shown in this figure, the liquid phase ratio tends to differ depending on the composition, even at the same temperature. Furthermore, the liquid phase ratio tends to differ depending on the temperature, even at the same composition.

[0048] Next, the sintering degree prediction unit 102 predicts the degree of sintering based on the liquidus ratio. The sintering degree prediction unit 102 predicts the degree of sintering, for example, using the table information storage unit 106.

[0049] The table information storage unit 106 stores table information that associates the degree of sintering with a combination of composition and temperature. The table information is created, for example, based on the results of adhesion experiments. In adhesion experiments, the state of deposits adhering to flues such as combustion exhaust gas ducts in actual fluidized bed incinerators is evaluated, or the state of deposits is evaluated through melting experiments. In evaluating the state of deposits, for each combination of incineration temperature and dewatered sludge composition, the presence or absence of deposits, and if deposits are present, the degree of solidification and amount of deposits are comprehensively considered to determine which of several adhesion levels, depending on the degree of sintering, applies, such as "no deposits," "deposits present," or "obvious deposits." The condition of the adhering material may be evaluated by a person in charge through visual inspection, or it may be evaluated quantitatively using an evaluation test device. In this case, the evaluation test device may be used to apply a constant pressure to the adhering material (residual material from incineration) using a digital force gauge, for example, and measure the force required to break the adhering material. The greater the bonding force of the particles constituting the residual material, that is, the more advanced the sintering, the greater the force required to break the material (the force required to break the residual material). Therefore, the condition of the adhering material can be evaluated quantitatively.

[0050] Figure 7 shows an example of information (table information) stored in the table information storage unit 106. As shown in this figure, the table information storage unit 106 stores information corresponding to the following items as liquid phase information: composition evaluation index value, temperature (incineration temperature), and degree of sintering. The composition evaluation index value is information indicating the composition of the dewatered sludge to be incinerated, and for example, similar to the liquid phase information, an evaluation index value X can be used. The temperature is information indicating the incineration temperature of the substance (in this case, dewatered sludge having a composition corresponding to the evaluation index value). The degree of sintering is information indicating the degree of sintering in the residue when the substance (in this case, dewatered sludge having a composition corresponding to the evaluation index value) is incinerated at the incineration temperature. This figure shows that when dewatered sludge with an evaluation index value X of E1 is incinerated at a temperature of 900°C, the degree of incineration is high, indicating "obvious adhesion." Furthermore, when dewatered sludge with an evaluation index value X of E3 is incinerated at a temperature of 900°C, the degree of incineration is "adhesion occurred." Finally, when dewatered sludge with an evaluation index value X of E4 is incinerated at a temperature of 900°C, the degree of incineration is "no adhesion."

[0051] Here, the method by which the sintering degree prediction unit 102 predicts the degree of sintering using the table information storage unit 106 will be explained with reference to Figure 8. Figure 8 is a diagram illustrating the process by which the sintering degree prediction unit 102 of the sintering control device 100 predicts the degree of sintering.

[0052] The sintering degree prediction unit 102 plots points P (points P1 to P3 in this figure) corresponding to the combination of composition and temperature in the table information stored in the table information storage unit 106 on a graph that visualizes the liquidus fraction as shown in Figure 6. In this figure, point P1 corresponds to the conditions of index value E1 and incineration temperature of 900 [°C] in the table information storage unit 106, and indicates that the actual degree of incineration relative to the liquid phase ratio at point P1 is "clear adhesion present". Point P2 corresponds to the conditions of index value E3 and incineration temperature of 900 [°C] in the table information storage unit 106, and indicates that the actual degree of incineration relative to the liquid phase ratio at point P2 is "adhesion occurring". Point P3 corresponds to the conditions of index value E4 and incineration temperature of 900 [°C] in the table information storage unit 106, and indicates that the actual degree of incineration relative to the liquid phase ratio at point P3 is "no adhesion".

[0053] In this way, the sintering degree prediction unit 102 associates the liquid phase ratio with the sintering degree by superimposing liquid phase information and table information according to the combination of composition and temperature. The sintering degree prediction unit 102 predicts the sintering degree of dewatered sludge to be one that has a liquid phase ratio within a predetermined range from the reference liquid phase ratio, for example, using the liquid phase ratio corresponding to the sintering degree shown in the table information as a reference. The predetermined range here is a range set in relation to the liquid phase ratio (first liquid phase ratio) associated with a certain sintering degree (first sintering degree) and the liquid phase ratio (second liquid phase ratio) associated with another sintering degree (second sintering degree). For example, the intermediate liquid phase ratio in the range from the first liquid phase ratio to the second sintering degree is the boundary between the first and second sintering degrees.

[0054] For example, if the result of overlaying table information onto liquid phase information is as shown in Figure 8, then at an incineration temperature of 900°C, the sintering degree prediction unit 102 sets the standard liquid phase ratio corresponding to a sintering degree of "no adhesion" to approximately 5%. The standard liquid phase ratio corresponding to a sintering degree of "adhesion occurring" to approximately 15%. The standard liquid phase ratio corresponding to a sintering degree of "clearly present" to approximately 60%. The sintering degree prediction unit 102 sets the midpoint (approximately 10%) between the standard liquidus ratio (approximately 5%) corresponding to the sintering degree "no adhesion" and the standard liquidus ratio (approximately 15%) corresponding to the sintering degree "adhesion occurred" as the boundary between the sintering degree "no adhesion" and the sintering degree "adhesion occurred". The sintering degree prediction unit 102 also sets the midpoint (approximately 37.5%) between the standard liquidus ratio (approximately 15%) corresponding to the sintering degree "adhesion occurred" and the standard liquidus ratio (approximately 60%) corresponding to the sintering degree "obvious adhesion present" as the boundary between the sintering degree "no adhesion" and the sintering degree "obvious adhesion present". In this case, the sintering degree prediction unit 102 predicts that the sintering degree is "no adhesion" if the liquid phase ratio of the dewatered sludge to be incinerated is 0% or more and less than 10%. The sintering degree prediction unit 102 also predicts that the sintering degree is "adhesion occurring" if the liquid phase ratio of the dewatered sludge to be incinerated is 10% or more and less than 37.5%. The sintering degree prediction unit 102 also predicts that the sintering degree is "clear adhesion present" if the liquid phase ratio of the dewatered sludge to be incinerated is 37.5% or more.

[0055] The addition amount calculation unit 103 calculates the amount of basic substance to be added to the dewatered sludge. If the degree of sintering predicted by the degree of sintering prediction unit 102 for the dewatered sludge to be incinerated is greater than a threshold, for example, a degree of sintering of "no adhesion", the addition amount calculation unit 103 calculates the amount of basic substance to be added in order to reduce the degree of sintering to the threshold of "no adhesion".

[0056] For example, if the degree of sintering predicted by the degree of sintering prediction unit 102 is "adhesion occurring," and the corresponding liquidus ratio is 20%, and the composition evaluation index value is value E4, the addition amount calculation unit 103 calculates the amount to be added to bring the composition evaluation index value to E1, which corresponds to the standard liquidus ratio of 5%, corresponding to a degree of sintering "no adhesion." Here, the addition amount calculation unit 103 calculates the amount to be added according to the base substance to be added. For example, when adding Ca (calcium) as the base substance, the addition amount calculation unit 103 derives a relationship between the evaluation index value X and Ca, where the amounts of phosphorus and base substances other than Ca are fixed, and Ca is a variable, in the calculation formula (for example, any of formulas (1) to (2)) used in the prediction of the degree of sintering prediction unit 102. Using the derived relationship, the addition amount calculation unit 103 calculates the amount of Ca to be added so that the evaluation index value X becomes the target value E1.

[0057] By adding the amount of base substance calculated by the addition amount calculation unit 103, the ratio of base substance component to phosphorus component increases, and the evaluation index value X increases. By increasing the evaluation index value X, the liquid phase ratio is reduced when incinerated at the same incineration temperature as before the addition, thereby reducing the degree of sintering which correlates with the liquid phase ratio, and mitigating the possibility of sintering occurring.

[0058] The output unit 104 outputs various information. For example, the output unit 104 outputs the degree of sintering predicted by the degree of sintering prediction unit 102. The output unit 104 may also output the base substance to be added and the amount to be added, which are calculated by the addition amount calculation unit 103. The output unit 104 displays the output information by outputting various information to a display (not shown) connected to the sintering control device 100, for example. The output unit 104 may also display a three-dimensional graph visualizing the liquid phase ratio, as shown in Figure 6, or a three-dimensional graph associating liquid phase information with table information, as shown in Figure 8. Furthermore, the output unit 104 may transmit various information to the sewage treatment facility SB by outputting various information to the sewage treatment facility SB. For example, the output unit 104 notifies the additive device of the basic substance to be added and the amount to be added in the basic substance addition step 8. The additive device adds the amount of basic substance notified by the output unit 104 to the sludge or dewatered sludge. This allows for control so that an appropriate amount of basic substance is added to the sludge from the viewpoint of suppressing sintering.

[0059] Here, the process by which the sintering control device 100 predicts the degree of sintering of the dewatered sludge to be incinerated will be explained using Figure 9. Figure 9 is a flowchart showing the flow of the process performed by the sintering control device 100 in this embodiment.

[0060] As shown in Figure 9, in the process of predicting the degree of sintering of dewatered sludge to be incinerated, the acquisition unit 101 of the sintering control device 100 acquires the incineration temperature of the fluidized bed incinerator from the sewage treatment facility SB, etc. (step S201). The acquisition unit 101 of the sintering control device 100 acquires the composition evaluation index value X for the dewatered sludge to be incinerated from the calculation unit 73 of the sampling and analysis process 7 (step S202). The degree of sintering prediction unit 102 of the sintering control device 100 predicts the liquid phase ratio corresponding to the temperature acquired in step S101 and the composition acquired in step S102 using a liquid phase ratio prediction model (step S203). The degree of sintering prediction unit 102 of the sintering control device 100 predicts the degree of sintering of the dewatered sludge to be incinerated by associating the liquid phase ratio predicted in step S103 with the table information storage unit 106 (step S204). The additive amount calculation unit 103 of the sintering control device 100 calculates the amount of basic substance to be added to suppress sintering (step S205). The output unit 104 of the sintering control device 100 outputs the degree of sintering predicted in step S104 and the amount of additive calculated in step S105 (step S206).

[0061] The sintering control device 100 of the embodiment described above comprises an acquisition unit 101, a sintering degree prediction unit 102, and an output unit 104. The acquisition unit 101 acquires information indicating the composition of the dewatered sludge to be incinerated, and the incineration temperature at which the dewatered sludge is incinerated. The sintering degree prediction unit 102 predicts the degree of sintering when the dewatered sludge to be incinerated is incinerated at the incineration temperature, based on the liquid phase ratio predicted based on the combination of composition and temperature acquired by the acquisition unit 101, and table information that associates the degree of sintering with the combination of composition and incineration temperature. The output unit 104 outputs the degree of sintering predicted by the sintering degree prediction unit 102. As a result, the sintering control device 100 of the embodiment can quantitatively predict the risk of sintering occurring due to the incineration of dewatered sludge. In particular, by focusing on the correlation between the liquidus fraction and the degree of sintering, the liquidus fraction is calculated using thermodynamic equilibrium calculations. By correlating the calculated liquidus fraction with the degree of sintering observed in actual adhesion conditions evaluated in adhesion experiments, it is possible to predict the degree of sintering for compositions with limited incineration experience, such as dewatered sludge with increased phosphorus concentration. Furthermore, the degree of sintering can be predicted not only based on composition but also on combinations of composition and temperature, allowing for accurate prediction of the degree of sintering even when incineration is performed at higher temperatures in consideration of global warming.

[0062] Furthermore, in the sintering control device 100 of the embodiment, the sintering degree prediction unit 102 uses a liquid phase ratio prediction model that has learned the correspondence between the combination of composition and temperature of dewatered sludge and the liquid phase ratio to predict the liquid phase ratio corresponding to the combination of composition and temperature acquired by the acquisition unit, and predicts the sintering degree, which is associated with the combination of composition and temperature corresponding to the predicted liquid phase ratio in the table information, as the sintering degree when the dewatered sludge to be incinerated is incinerated at the incineration temperature.

[0063] Furthermore, the sintering control device 100 of this embodiment is further equipped with an additive amount calculation unit 103. The additive amount calculation unit 103 calculates the amount of basic substance to be added to the dewatered sludge to be incinerated based on the degree of sintering predicted by the degree of sintering prediction unit 102. The output unit 104 outputs the amount of additive calculated by the additive amount calculation unit 103. As a result, the sintering control device 100 of this embodiment can quantitatively predict the risk of sintering occurring due to the incineration of dewatered sludge and then calculate an appropriate amount of basic substance to be added to suppress the occurrence of sintering. Therefore, it is possible to suppress the addition of excessive amounts of basic substance unnecessarily in incineration operations at higher temperatures that take global warming into consideration, thereby enjoying economic benefits while suppressing the risk of sintering occurring, and enabling economical and stable sludge incineration.

[0064] Furthermore, the sintering control device 100 of this embodiment further includes a learning data generation unit 107 and a prediction model generation unit 108. The learning data generation unit 107 calculates learning data. The learning data is learning data to be trained on the regression model 301, and is data in which the liquid phase ratio corresponding to the combination of composition and temperature is associated. The learning data generation unit 107 calculates the learning data using a thermodynamic equilibrium calculation method (liquid phase ratio calculation unit 201). The prediction model generation unit 108 generates a liquid phase ratio prediction model by training the regression model 301 with the learning data generated by the learning data generation unit 107. As a result, in the sintering control device 100 of this embodiment, it is not necessary for the acquisition unit 101 to calculate the liquid phase ratio using thermodynamic equilibrium calculation software each time it acquires composition and temperature, and the liquid phase ratio can be predicted using the prediction model. In addition, by using data calculated using thermodynamic equilibrium calculation software as learning data, the liquid phase ratio can be predicted with the same accuracy as when thermodynamic equilibrium calculation software is used.

[0065] Furthermore, in the sintering control device 100 of this embodiment, the learning data storage unit 109 generates a liquid phase fraction prediction model by training a regression model that predicts the liquid phase fraction, which is the output, according to the combination of composition and temperature, which is the input, using a function that has continuity. As a result, the sintering control device 100 of this embodiment can use a function that can be expressed by a mathematical formula in the liquid phase fraction prediction model, and the processing load of calculations can be reduced compared to when thermodynamic equilibrium calculation software is used or when a trained model such as deep learning or a neural network is used.

[0066] Now, a modified example of this embodiment will be described. In this modified example, the functions of the sintering control device 100 are provided in the sewage treatment facility SB. In the following description, the configurations that differ from the embodiment described above will be mainly described, and the same reference numerals will be used for configurations equivalent to those in the embodiment described above, and their descriptions will be omitted.

[0067] Figure 10 is a diagram showing the system configuration of a modified sintering control system 400 according to the embodiment. As shown in Figure 10, in this modified embodiment, the sewage treatment facility SB is equipped with a sintering control device 100A. The sintering control device 100A has the functions related to the sampling and analysis process 7 of the embodiment described above, and the functions related to the sintering control device 100. The sintering control device 100A includes, for example, a composition evaluation index calculation unit 110, an acquisition unit 101, a sintering degree prediction unit 102, an additive amount calculation unit 103, an output unit 104, a liquid phase fraction prediction model storage unit 105, a table information storage unit 106, a learning data generation unit 107, a prediction model generation unit 108, and a learning data storage unit 109. The composition evaluation index calculation unit 110 has functions corresponding to the sampling means 71, the analysis device 72, and the calculation device 73, respectively. The composition evaluation index calculation unit 110 samples an analytical sample from the dewatered sludge, analyzes the components contained in the sampled sample, and calculates a composition evaluation index value X in the dewatered sludge from the amount of each analyzed component. The composition evaluation index calculation unit 110 outputs the value of the evaluation index value X, which is information indicating the composition of the dewatered sludge, to the acquisition unit 101. The acquisition unit 101 acquires the evaluation index value X output from the calculation device 73. The output unit 104 outputs the amount of additive calculated by the addition amount calculation unit 103 to the addition device of the basic substance addition step 8.

[0068] As described above, the wastewater treatment equipment SB according to the modified embodiment is equipped with a sintering control device 100A. This makes it possible to incorporate into the existing wastewater treatment equipment SB a function that predicts the degree of sintering according to the combination of composition and temperature, as well as the composition alone.

[0069] Furthermore, the sewage treatment facility SB according to the modified embodiment includes an additive device. The additive device is a device for adding a basic substance to the dewatered sludge to be incinerated or to the sludge before dewatering. The sintering control device 100A is connected to the additive device in a communicative manner. The sintering control device 100A has an additive amount calculation unit 103. The additive amount calculation unit 103 calculates the amount of basic substance to be added to the dewatered sludge to be incinerated based on the degree of sintering predicted by the degree of sintering prediction unit 102. The output unit 104 outputs the amount of additive calculated by the additive amount calculation unit 103 to the additive device. As a result, the sewage treatment facility SB according to the modified embodiment can suppress the unnecessary addition of large amounts of basic substance during incineration operation at higher temperatures that take global warming into consideration, thereby enjoying economic benefits while suppressing the risk of sintering occurring, and enabling economical and stable sludge incineration.

[0070] The sewage treatment equipment SB, sintering control device 100, and sintering control system 400 in the above-described embodiment may be implemented using a computer. In that case, the program for implementing this function may be recorded on a computer-readable recording medium, and the program recorded on this recording medium may be loaded into a computer system and executed. Here, "computer system" includes hardware such as an OS and peripheral devices. Furthermore, "computer-readable recording medium" refers to portable media such as flexible disks, magneto-optical disks, ROMs, CD-ROMs, and storage devices such as hard disks built into a computer system. Moreover, "computer-readable recording medium" may also include those that dynamically hold programs for a short period of time, such as communication lines used when transmitting programs via networks such as the Internet or communication lines such as telephone lines, and those that hold programs for a certain period of time, such as volatile memory inside a computer system that acts as a server or client in such cases. Furthermore, the above-mentioned program may be for implementing a part of the above-mentioned function, or it may be a program that can implement the above-mentioned function in combination with a program already recorded in the computer system, or it may be implemented using a programmable logic device such as an FPGA (Field Programmable Gate Array).

[0071] While embodiments of this invention have been described in detail above with reference to the drawings, the specific configuration is not limited to these embodiments and includes designs and the like that do not depart from the spirit of this invention. [Explanation of Symbols]

[0072] 100...Sintering control device, 101...Acquisition unit, 102...Sintering degree prediction unit (prediction unit), 103...Addition amount calculation unit, 104...Output unit, 200...Calculation device, 300...Learning device, 400...Sintering control system, SB...Wastewater treatment equipment

Claims

1. An acquisition unit that acquires information indicating the composition of the dewatered sludge to be incinerated, and the incineration temperature for incinerating the dewatered sludge, A prediction unit predicts the degree of sintering when the dewatered sludge to be incinerated is incinerated at the incineration temperature, based on the liquid phase ratio predicted based on the combination of composition and temperature obtained by the acquisition unit, and table information that associates the degree of sintering with the combination of composition and incineration temperature. An output unit that outputs the degree of sintering predicted by the prediction unit, A sintering control device equipped with the following:

2. The prediction unit uses a liquid phase ratio prediction model that has learned the correspondence between the composition and temperature combinations of dewatered sludge and the incineration temperature and the liquid phase ratio to predict the liquid phase ratio corresponding to the composition and temperature combinations obtained by the acquisition unit, and predicts the degree of sintering, which is associated in the table information with the composition and temperature combinations corresponding to the predicted liquid phase ratio, as the degree of sintering when the dewatered sludge to be incinerated is incinerated at the incineration temperature. The sintering control device according to claim 1.

3. The system further includes an additive amount calculation unit that calculates the amount of basic substance to be added to the dewatered sludge to be incinerated based on the degree of sintering predicted by the prediction unit. The output unit outputs the amount of additive calculated by the additive amount calculation unit. The sintering control device according to claim 1.

4. A learning data generation unit generates liquid phase fractions as learning data, calculated using a thermodynamic equilibrium calculation method that predicts the state of the substance in a thermodynamic equilibrium state according to the composition and temperature of the substance, and corresponding to the combination of composition and temperature. A prediction model generation unit generates the liquid phase fraction prediction model by training a regression model with the learning data generated by the learning data generation unit, The sintering control device according to claim 2, further comprising:

5. The prediction model generation unit generates the liquid phase fraction prediction model by training a regression model, which predicts the liquid phase fraction as an output according to the combination of composition and temperature inputs, using a continuous function, with training data. The sintering control device according to claim 4.

6. A sewage treatment facility comprising the sintering control device described in claim 1.

7. It has an additive device for adding basic substances to dewatered sludge or sludge before dewatering that is to be incinerated, The sintering control device is The additive device is connected in a manner that allows it to communicate with the additive device, The system includes an additive amount calculation unit that calculates the amount of basic substance to be added to the dewatered sludge to be incinerated based on the degree of sintering predicted by the prediction unit, The output unit outputs the amount of additive calculated by the additive amount calculation unit to the additive device. The wastewater treatment facility according to claim 6.

8. A sintering control method performed by a computer, which is a sintering control device, The acquisition unit acquires information indicating the composition of the dewatered sludge to be incinerated, and the incineration temperature at which the dewatered sludge is incinerated. The prediction unit predicts the degree of sintering when the dewatered sludge to be incinerated is incinerated at the incineration temperature, based on the liquid phase ratio predicted based on the combination of composition and temperature obtained by the acquisition unit, and table information that associates the degree of sintering with the combination of composition and incineration temperature. The output unit outputs the degree of sintering predicted by the prediction unit. Sintering control method.

9. The computer, which is a sintering control device, An acquisition means for obtaining information indicating the composition of the dewatered sludge to be incinerated, and the incineration temperature for incinerating the dewatered sludge, A prediction means for predicting the degree of sintering when dewatered sludge to be incinerated is incinerated at the incineration temperature, based on the liquid phase ratio predicted based on the acquired combination of composition and temperature, and table information that associates the degree of sintering with the combination of composition and incineration temperature. An output means for outputting the predicted degree of sintering, A program designed to function as such.

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