Incineration system and supply control method

Abstract

To provide an incineration system and a supply control method capable of reducing a greenhouse gas emission amount derived from a supplemental fuel such as a fossil fuel, and suppressing an emission amount of nitrogen oxide.SOLUTION: An incineration system comprises: an incineration furnace for incinerating a material to be incinerated; and a supply unit for supplying ammonia to each of a first position at which the material to be incinerated is incinerated in the incineration furnace and a second position through which a gas generated accompanied by the incineration of the material to be incinerated flows.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to incineration systems and feed control methods. [Background technology]

[0002] In an incineration system (hereinafter simply referred to as an incineration system) that includes an incinerator (hereinafter simply referred to as an incinerator) that incinerates materials to be incinerated, for example, the incineration of the materials to be incinerated may be performed using auxiliary fuel. On the other hand, if a fossil fuel is used as the auxiliary fuel in an incineration system, the amount of greenhouse gas emissions such as carbon dioxide (CO2) increases.

[0003] Therefore, in order to reduce greenhouse gas emissions in the incineration systems described above, efforts are being made to use carbon-free fuels as auxiliary fuels, for example, instead of fossil fuels, etc. Specifically, in incineration systems, for example, ammonia, which is a carbon-free fuel, is sometimes used as auxiliary fuel (see Non-Patent Document 1).

[0004] In the incineration system, for example, when combustion is performed using carbon-free fuel as an auxiliary fuel, nitrogen oxides (e.g., NO x NO is produced. x N2O is an air pollutant and emission standards have been established, so if emissions are high, they must be reduced.N2O is also a greenhouse gas with a greenhouse effect 298 times greater than CO2, so emissions must be reduced in order to combat global warming.

[0005] Therefore, in incineration systems, for example, when carbon-free fuel is used as an auxiliary fuel, a method of raising the temperature inside the incinerator (high-temperature incineration) is widely used in order to reduce the amount of NO emitted during combustion.

[0006] However, in incineration systems, the higher the combustion temperature, the lower the NO xTherefore, in an incineration system, for example, if high-temperature incineration measures are implemented to reduce N2O, it is possible to reduce N2O emissions, but at the same time, NO x The increase in emissions cannot be contained. [Prior art documents] [Non-patent literature]

[0007] [Non-Patent Document 1] Daichi Tanaka, Ryo Yoshiie, Ichiro Naruse, Yasuaki Ueki, Masato Endo, and Takuya Kawai, "Co-combustion of digested sludge and ammonia in a fluidized bed," Presentation manuscript for the 33rd Research Conference of the Japan Society of Material Cycles and Waste Management, 2022, pp. 305-306 Summary of the Invention [Problem to be solved by the invention]

[0008] In the incineration system described above, for example, greenhouse gas emissions from auxiliary fuels such as fossil fuels are reduced, and various nitrogen oxides (e.g., NO) generated during the combustion of the incineration material are reduced. x It is hoped that both reductions in CO2 and N2O emissions will be achieved. [Means for solving the problem]

[0009] The incineration system of the present disclosure includes an incinerator that incinerates materials to be incinerated, and a supply unit that supplies ammonia to a first position within the incinerator where the materials to be incinerated are incinerated and to a second position through which gas generated by the incineration of the materials to be incinerated flows. [Effects of the Invention]

[0010] The incineration system and supply control method disclosed herein make it possible to reduce greenhouse gas emissions and suppress nitrogen oxide emissions derived from auxiliary fuels such as fossil fuels. [Brief explanation of the drawings]

[0011] [Figure 1]FIG. 1 is a diagram illustrating an example of the configuration of an incineration system 100 according to the first embodiment. [Figure 2] FIG. 2 is a diagram illustrating an example of the configuration of the incineration system 100 according to the first embodiment. [Figure 3] FIG. 3 is a graph showing the relationship between the incineration temperature of sludge in the incinerator 1 and the conversion rate of nitrogen components contained in the sludge etc. to nitrogen oxides (NOx and N2O). [Figure 4] FIG. 4 is a diagram illustrating the hardware configuration of the control device 10. As shown in FIG. [Figure 5] FIG. 5 is a flowchart illustrating supply control in the first embodiment. [Figure 6] FIG. 6 is a flowchart illustrating the details of S13 in FIG. [Figure 7] FIG. 7 is a diagram illustrating an example of the configuration of an incineration system 100 in a first modified example. [Figure 8] FIG. 8 is a diagram illustrating an example of the configuration of an incineration system 200 according to the second embodiment. [Figure 9] FIG. 9 is a flowchart illustrating supply control in the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. However, such descriptions should not be interpreted in a limiting sense, and do not limit the subject matter described in the claims. Furthermore, various changes, substitutions, and modifications can be made without departing from the spirit and scope of the present disclosure. Furthermore, different embodiments can be combined as appropriate.

[0013] [Incineration system 100 in the first embodiment] First, an incineration system 100 according to the first embodiment will be described. FIGS. 1 and 2 are diagrams illustrating an example of the configuration of the incineration system 100 according to the first embodiment. FIG. 3 shows the relationship between the incineration temperature of sludge in the incinerator 1 and nitrogen oxides (NO ) of nitrogen components contained in the sludge. x 1 is a graph showing the relationship between the conversion rate from CO to N2O and N2O. Note that the arrangement positions, lengths, and numbers of pipes shown below are examples and are not limited to these.

[0014] 1, the incineration system 100 includes, for example, an incinerator 1, an ammonia storage tank 2, a vaporizer 3, a blower B1, a pressure regulator P1, and a pressure regulator P2. Below, we will explain the case where the material to be incinerated is sewage sludge (hereinafter simply referred to as sludge).

[0015] The incinerator 1 is, for example, a furnace that incinerates sludge (dewatered sludge) supplied via a pipe L11. The pipe L11 is, for example, a pipe that connects the incinerator 1 to a upstream equipment (for example, a dryer). Specifically, the incinerator 1 is, for example, a fluidized bed incinerator, and has a so-called fluidized bed 1a. The exhaust gas G1 (hereinafter also simply referred to as exhaust gas G1) discharged from the incinerator 1 is supplied to a downstream equipment (for example, a fluidized air preheater) of the incinerator 1 via the pipe L1. The pipe L1 is, for example, a pipe that connects the outlet side of the incinerator 1 for the exhaust gas G1 with the inlet side of the downstream equipment of the incinerator 1 for the exhaust gas G1.

[0016] The following description will be given assuming that the incinerator 1 is a fluidized bed incinerator, but the present invention is not limited to this. Specifically, the incinerator 1 may be, for example, various types of incinerators other than a fluidized bed incinerator (for example, a stoker-type incinerator).

[0017] The blower B1 supplies combustion air to the incinerator 1 via, for example, a pipe L21. The pipe L21 is, for example, a pipe that connects the outlet side of the blower B1 with the inlet side of the incinerator 1 for combustion air.

[0018] The ammonia storage tank 2 is, for example, a tank that stores liquid ammonia (hereinafter also referred to as liquefied ammonia). The liquefied ammonia is supplied to the vaporizer 3 via a pipe L2 by, for example, a pump (not shown). The pipe L2 is, for example, a pipe that connects the ammonia storage tank 2 and the vaporizer 3.

[0019] The vaporizer 3 generates gaseous ammonia (hereinafter also referred to as ammonia gas G2) by vaporizing liquefied ammonia supplied from the ammonia storage tank 2 via, for example, pipe L2. A portion of the ammonia gas G2 is supplied from the vaporizer 3 via, for example, pipe L3 to a position in the incinerator 1 where sludge is incinerated (for example, a sand layer or a freeboard layer in the incinerator 1). The pipe L3 is, for example, a pipe connecting the outlet side of the ammonia gas G2 in the vaporizer 3 with the inlet side of the ammonia gas G2 in the incinerator 1. Another portion of the ammonia gas G2 is supplied to the pipe L1 via, for example, a portion of the pipe L3 and pipe L4. The pipe L4 is, for example, a pipe branched from the pipe L3 and connected to the pipe L1. Hereinafter, the ammonia gas G2 will also be simply referred to as ammonia.

[0020] The pressure regulator P1 is provided, for example, in the rear stage (incinerator 1 side) of the branching position of the pipe L3 with the pipe L4, and regulates (depressurizes) the pressure of the ammonia gas G2 supplied from the vaporizer 3. Then, the ammonia gas G2 whose pressure has been regulated by the pressure regulator P1 is supplied to the incinerator 1, for example, when a valve V1 provided in the pipe L3 is open.

[0021] The pressure regulator P2 is provided, for example, in the pipe L4, and regulates (depressurizes) the pressure of the ammonia gas G2 supplied from the vaporizer 3. Then, the ammonia gas G2 whose pressure has been regulated in the pressure regulator P2 is supplied to the pipe L1, for example, when a valve V2 provided in the pipe L4 is open.

[0022] The ammonia gas G2 generated in the vaporizer 3 is, for example, a high-pressure gas. Therefore, the ammonia gas G2 is supplied to the incinerator 1 via a pressure regulator P1 without using a pump or the like, and is also supplied to the pipe L1 via a pressure regulator P2.

[0023] That is, in the incineration system 100, for example, a part of the ammonia gas G2 stored in the ammonia storage tank 2 is supplied to the incinerator 1, and the part of the ammonia gas G2 is made to function as an auxiliary fuel that assists in the incineration of sludge in the incinerator 1. Also, in the incineration system 100, for example, another part of the ammonia gas G2 stored in the ammonia storage tank 2 is supplied to the pipe L1, and the other part of the ammonia gas G2 is made to function as an auxiliary fuel that assists in the incineration of sludge in the incinerator 1. x It functions as a reducing agent that reduces

[0024] Furthermore, the incineration system 100 has, for example, a thermometer T1 that measures the incineration temperature of sludge in the incinerator 1, as shown in FIG.

[0025] Furthermore, as shown in FIG. 2, the incineration system 100 includes, for example, a control device 10 that controls the supply of ammonia gas G2 to at least one of the incinerator 1 and the pipe L1.

[0026] The thermometer T1 is provided, for example, at a position in the incinerator 1 where sludge is incinerated, and measures the temperature inside the incinerator 1.

[0027] The control device 10 is, for example, an electronic device having an electronic circuit. Specifically, the control device 10 is, for example, one or more physical machines or one or more virtual machines having a CPU (Central Processing Unit) and a memory.

[0028] 2, the control device 10 controls the supply of ammonia gas G2 to at least one of the incinerator 1 and the pipe L1 (hereinafter also referred to as supply control) by controlling the opening and closing of at least one of the valves V1 and V2. Hereinafter, the valves V1 and V2 will be collectively referred to as the supply unit 20. In other words, the supply unit 20 is a mechanism capable of supplying ammonia gas G2 to at least one of the incinerator 1 and the pipe L1, for example.

[0029] Here, as shown in FIG. 3, the inventors have calculated the amount of N2O generated during the incineration of sludge in the incinerator 1 and the amount of NO x It was found that there is a trade-off between the amount of CO2 generated and the amount of CO2 generated.

[0030] Specifically, the inventors have found that, for example, as shown in graph GR1 in Fig. 3, the conversion rate of nitrogen components contained in sludge supplied to the incinerator 1 to N2O increases as the incineration temperature of the sludge in the incinerator 1 decreases. Also, as shown in graph GR2 in Fig. 3, the inventors have found that, for example, the conversion rate of nitrogen components contained in ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1 to N2O increases as the incineration temperature of the sludge in the incinerator 1 decreases. Also, as shown in graph GR3 in Fig. 3, the inventors have found that, for example, the conversion rate of nitrogen components contained in ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1 to N2O increases as the incineration temperature of the sludge in the incinerator 1 decreases. x The inventors have found that the conversion rate of NO to NH3 increases with an increase in the incineration temperature of the sludge in the incinerator 1. Furthermore, as shown in the graph GR4 in FIG. 3, the inventors have found that the conversion rate of NO to NH3 increases with an increase in the incineration temperature of the sludge in the incinerator 1. x It was found that the conversion rate to CO₂ was almost constant regardless of the incineration temperature of the sludge in the incinerator 1.

[0031] In other words, the inventors have found that, for example, when the incineration temperature of sludge in the incinerator 1 tends to increase, the amount of N2O generated in the incinerator 1 tends to decrease, and the amount of NO xFurthermore, the inventors have found that, for example, when the incineration temperature of sludge in the incinerator 1 tends to decrease, the amount of N2O generated in the incinerator 1 tends to increase, and the amount of NO generated in the incinerator 1 tends to decrease. x It was found that the amount of generated water tends to decrease.

[0032] Therefore, the control device 10 in this embodiment raises the incineration temperature of the sludge in the incinerator 1 by, for example, supplying a necessary amount of ammonia gas G2 (auxiliary fuel) to the incinerator 1, thereby suppressing the amount of N2O emitted from the incinerator 1. In addition, the control device 10 in this embodiment reduces the amount of NO2O that has increased with the rise in the incineration temperature of the sludge in the incinerator 1 by, for example, supplying a necessary amount of ammonia gas G2 (reducing agent) to the pipe L1. x and reduces NO from incinerator 1. x Reduce emissions.

[0033] Specifically, the control device 10 controls, for example, depending on the incineration status in the incinerator 1, at least one of the supply of ammonia gas G2 (auxiliary fuel) to a position within the incinerator 1 where sludge is incinerated (hereinafter also referred to as the first position), and the supply of ammonia gas G2 (reducing agent) to a position within the pipe L1 (hereinafter also referred to as the second position).

[0034] More specifically, for example, when the incineration temperature of the sludge in the incinerator 1 (the incineration temperature measured by the thermometer T1) is equal to or higher than a predetermined threshold value (hereinafter also referred to as the first threshold value), the control device 10 controls the supply unit 20 so that at least one of the following is performed: a decrease in the amount of ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1, or an increase in the amount of ammonia gas G2 (reducing agent) supplied to the pipe L1.

[0035] That is, when the incineration temperature of the sludge in the incinerator 1 is equal to or higher than the first threshold, it can be determined that, for example, there is sufficient heat in the incinerator 1 and it is possible to sufficiently suppress the amount of N2O contained in the exhaust gas G1 discharged from the incinerator 1. Therefore, in this case, the control device 10 controls the supply unit 20, for example, to reduce the amount of ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1. Specifically, in this case, the control device 10 reduces the amount of ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1 by, for example, controlling the valve V1 to be smaller. Note that the control device 10 may also control the supply unit 20 in this case, for example, to stop the supply of ammonia gas G2 (auxiliary fuel) to the incinerator 1.

[0036] In addition, the case where the incineration temperature of the sludge in the incinerator 1 is equal to or higher than the first threshold value means, for example, that the NO 2 contained in the exhaust gas G1 discharged from the incinerator 1 is x It can be determined that this is the case where the amount of ammonia gas G2 (reducing agent) supplied to the pipe L1 (exhaust gas G1 flowing through the pipe L1) is increasing. Therefore, in this case, the control device 10 controls the supply unit 20, for example, to increase the supply amount of ammonia gas G2 (reducing agent) supplied to the pipe L1 (exhaust gas G1 flowing through the pipe L1). Specifically, in this case, the control device 10 increases the supply amount of ammonia gas G2 (reducing agent) supplied to the pipe L1 by, for example, controlling the valve V2 to increase the opening degree.

[0037] This allows the control device 10 to, for example, prevent ammonia gas G2 (auxiliary fuel) from being supplied more than necessary to the incinerator 1. In addition, the control device 10 can, for example, monitor not only the amount of N2O contained in the exhaust gas G1 discharged from the incinerator 1 but also the amount of NO x It is possible to suppress the amount of

[0038] In addition, for example, when the incineration temperature of the sludge in the incinerator 1 is less than a predetermined threshold value (hereinafter also referred to as the second threshold value) which is smaller than the first threshold value, the control device 10 controls the supply unit 20 so that at least one of an increase in the amount of ammonia gas G2 (auxiliary fuel) to the incinerator 1 and a decrease in the amount of ammonia gas G2 (reducing agent) to the pipe L1 is performed.

[0039] That is, when the incineration temperature of the sludge in the incinerator 1 is lower than the second threshold, it can be determined that, for example, the amount of heat in the incinerator 1 is insufficient and the amount of N2O contained in the exhaust gas G1 discharged from the incinerator 1 cannot be sufficiently suppressed. Therefore, in this case, the control device 10 controls the supply unit 20 so as to increase the supply amount of ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1. Specifically, in this case, the control device 10 increases the supply amount of ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1, for example, by controlling the valve V1 to increase the opening degree.

[0040] In addition, the case where the incineration temperature of the sludge in the incinerator 1 is lower than the second threshold value means, for example, that the NO 2 contained in the exhaust gas G1 discharged from the incinerator 1 is x It can be determined that this is the case where the amount of ammonia gas G2 (reducing agent) supplied to the pipe L1 is decreasing. Therefore, in this case, the control device 10 controls the supply unit 20, for example, to reduce the supply amount of ammonia gas G2 (reducing agent) supplied to the pipe L1 (exhaust gas G1 flowing through the pipe L1). Specifically, in this case, the control device 10 reduces the supply amount of ammonia gas G2 (reducing agent) supplied to the pipe L1 by, for example, controlling the valve V2 to be smaller. Note that in this case, the control device 10 may also control the supply unit 20, for example, to stop the supply of ammonia gas G2 (reducing agent) to the pipe L1.

[0041] As a result, the control device 10 detects, for example, NO contained in the exhaust gas G1 discharged from the incinerator 1. xIt is possible to suppress not only the amount of N2O but also the amount of N2O contained in the exhaust gas G1 discharged from the incinerator 1. Furthermore, the control device 10 can prevent, for example, ammonia gas G2 (reducing agent) from being supplied to the pipe L1 more than necessary.

[0042] In addition, the control device 10 may control the supply unit 20 so that, for example, when the incineration temperature of the sludge in the incinerator 1 is less than a first threshold value, at least one of increasing the amount of ammonia gas G2 (auxiliary fuel) to the incinerator 1 and decreasing the amount of ammonia gas G2 (reducing agent) to the pipe L1 is performed.

[0043] [Control device 10 in the first embodiment] Next, the hardware configuration of the control device 10 in the first embodiment will be described. FIG.

[0044] 4, the control device 10 is a computer device having, for example, a CPU 101 which is a processor, a memory 102, a communication device 103, and a storage medium 104. Each unit is connected to each other via, for example, a bus 105.

[0045] The storage medium 104 has, for example, a program storage area (not shown) that stores a program 110 for performing supply control. The storage medium 104 also has, for example, an information storage area 130 that stores information used when performing supply control. The storage medium 104 may be, for example, a hard disk drive (HDD) or a solid state drive (SSD).

[0046] The CPU 101 performs supply control by executing a program 110 loaded into the memory 102 from the storage medium 104, for example.

[0047] The communication device 103 accesses an operation terminal (not shown) through which the administrator of the incineration system 100 inputs necessary information, for example, via a network (not shown) such as the Internet.

[0048] The control device 10 may include, for example, a field programmable gate array (FPGA) or an application specific integrated circuit (ASIC), and the supply control may be performed by, for example, the FPGA or the ASIC.

[0049] In addition, the following description will be given assuming that the incineration system 100 has one control device 10, but this is not limiting. Specifically, the incineration system 100 may have, for example, multiple control devices 10. Furthermore, supply control may be distributed among, for example, the multiple control devices 10.

[0050] [Supply Control in the First Embodiment] Next, supply control in the first embodiment will be described below with reference to a flow chart diagram of Fig. 5, which explains supply control in the first embodiment.

[0051] The control device 10 waits, for example, until a first timing occurs. The first timing may be a regular timing, for example, every minute.

[0052] Then, for example, when the first timing arrives, the control device 10 determines whether or not the incineration state in the incinerator 1 satisfies a predetermined condition (hereinafter also referred to as the first condition) as shown in Figure 5 (Step S11 in Figure 5). The first condition is, for example, that the incineration temperature in the incinerator 1 is equal to or higher than a first threshold value, or that the incineration temperature in the incinerator 1 is lower than a second threshold value.

[0053] Specifically, the control device 10 acquires the incineration temperature (the incineration temperature of the sludge in the incinerator 1) measured by, for example, the thermometer T1, and determines whether the acquired incineration temperature satisfies the first condition.

[0054] As a result, when it is determined in step S11 that the incineration state in the incinerator 1 satisfies the first condition (YES in step S12 in FIG. 5), the control device 10 controls, for example, the supply unit 20 (step S13 in FIG. 5).

[0055] Specifically, for example, when the control device 10 determines that the incineration temperature measured by the thermometer T1 is equal to or higher than the first threshold, it controls the valve V1 to decrease the opening degree, thereby reducing the supply amount of ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1. In this case, the control device 10 also controls the valve V2 to increase the opening degree, thereby increasing the supply amount of ammonia gas G2 (reducing agent) supplied to the pipe L1.

[0056] Furthermore, for example, when it is determined that the incineration temperature measured by the thermometer T1 is less than the second threshold value, the control device 10 increases the supply amount of ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1, for example, by controlling the valve V1 to be larger. In this case, the control device 10 also decreases the supply amount of ammonia gas G2 (reducing agent) supplied to the pipe L1, for example, by controlling the valve V2 to be smaller.

[0057] Returning to FIG. 5, if it is determined in step S11 that the incineration state in the incinerator 1 does not satisfy the first condition (NO in step S12 in FIG. 5), the control device 10 may not perform step S13, for example.

[0058] Thus, the incineration system 100 in this embodiment includes, for example, an incinerator 1 that incinerates the materials to be incinerated, and a supply unit 20 that supplies ammonia gas G2 to a first position within the incinerator 1 where the materials to be incinerated are incinerated and a second position through which gas (exhaust gas G1) generated in conjunction with the incineration of the materials to be incinerated flows.

[0059] Furthermore, the incineration system 100 in this embodiment has, for example, a control device 10 that controls at least one of the supply of ammonia gas G2 to the first position and the supply of ammonia gas G2 to the second position. The control device 10 controls at least one of the supply of ammonia gas G2 to the first position and the supply of ammonia gas G2 to the second position, for example, depending on the incineration status in the incinerator 1.

[0060] Specifically, for example, when the incineration temperature of the material to be incinerated in the incinerator 1 becomes equal to or higher than a first threshold value, the control device 10 performs at least one of control to reduce the amount of ammonia gas G2 supplied to the first position and control to increase the amount of ammonia gas G2 supplied to the second position.

[0061] In addition, for example, when the incineration temperature of the material to be incinerated in the incinerator 1 becomes lower than a first threshold value or a second threshold value lower than the first threshold value, the control device 10 performs at least one of control to increase the amount of ammonia gas G2 supplied to the first position and control to decrease the amount of ammonia gas G2 supplied to the second position.

[0062] As a result, the incineration system 100 in this embodiment can, for example, compare the amount of N2O emitted from the incinerator 1 and the amount of NO emitted from the incinerator 1. x This will make it possible to reduce both carbon dioxide emissions and CO2 emissions.

[0063] Furthermore, in the incineration system 100 of this embodiment, for example, by supplying ammonia gas G2 stored in an ammonia storage tank 2 (for example, a single tank) to both the incinerator 1 and the piping L1, it becomes unnecessary to separately manage the ammonia gas G2 used as auxiliary fuel and the ammonia gas G2 used as a reducing agent. Therefore, in the incineration system 100 of this embodiment, for example, it becomes possible to reduce the workload and costs required to supply ammonia gas G2 to both the incinerator 1 and the piping L1.

[0064] In addition, the incineration system 100 in this embodiment can measure, for example, the concentration of N2O emitted from the incinerator 1 and the concentration of NO2O emitted from the incinerator 1. x Therefore, the incineration system 100 in this embodiment can control at least one of the amount of ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1 and the amount of ammonia gas G2 (reducing agent) supplied to the pipe L1 without measuring the concentration of N2O emitted from the incinerator 1. x This makes it possible to start the control of the amount of ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1 and the control of the amount of ammonia gas G2 (reducing agent) supplied to the pipe L1 earlier than when control is performed using the measurement results of the concentration of ammonia gas G2 (auxiliary fuel). In other words, the incineration system 100 in this embodiment makes it possible to prevent delays in the control of the amount of ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1 and the control of the amount of ammonia gas G2 (reducing agent) supplied to the pipe L1, for example.

[0065] [Details of S13 in Figure 5] Next, details of S13 in Fig. 5 will be described. Fig. 6 is a diagram for explaining details of S13 in Fig. 5. Specifically, Fig. 6 is a flowchart for explaining details of S13 in Fig. 5.

[0066] In S13, the control device 10 calculates the supply amount of ammonia gas G2 (reducing agent) to the pipe L1 by using, for example, the supply amount of sludge to the incinerator 1 (e.g., the supply amount per unit time), the incineration temperature of the sludge in the incinerator 1, and the supply amount of ammonia gas G2 (auxiliary fuel) to the incinerator 1 (e.g., the supply amount per unit time).

[0067] Specifically, as shown in Fig. 6, the control device 10 acquires, for example, the incineration temperature (the incineration temperature of sludge in the incinerator 1) measured by a thermometer T1. Then, for example, if the acquired incineration temperature is equal to or higher than a first threshold, the control device 10 reduces the amount of ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1. Furthermore, for example, if the acquired incineration temperature is lower than a second threshold, the control device 10 increases the amount of ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1. Thereafter, the control device 10 identifies (acquires) the supply amount (hereinafter also referred to as the first supply amount) of ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1, for example, from the opening degree of valve V1 or the like (step S21 in Fig. 6).

[0068] Next, the control device 10 converts the conversion rate corresponding to the incineration temperature acquired in step S21 into the NO of the nitrogen component contained in the sludge supplied to the incinerator 1, for example, by referring to the graph GR3 in FIG. x (hereinafter, also referred to as a first conversion rate) (step S22 in FIG. 6).

[0069] Then, the control device 10 acquires the amount of sludge supplied (the amount of sludge supplied to the incinerator 1) measured by, for example, a flow meter (not shown) provided in the pipe L11. Furthermore, the control device 10 calculates the NOx generated from the sludge supplied to the incinerator 1 by, for example, multiplying the acquired amount of sludge supplied, the proportion of nitrogen components contained in the acquired sludge, and the first conversion rate specified in step S22. x The amount of is calculated (predicted) (step S23 in FIG. 6).

[0070] Subsequently, the control device 10 calculates the conversion rate corresponding to the incineration temperature acquired in step S21 by referring to, for example, the graph GR4 in FIG. 3, as the NO of the nitrogen component contained in the ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1. x (hereinafter, also referred to as a second conversion rate) (step S24 in FIG. 6).

[0071] Then, the control device 10 calculates the NO 2 generated from the ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1 by, for example, multiplying the first supply amount determined in step S21 by the second conversion rate determined in step S24. x The amount of is calculated (predicted) (step S25 in FIG. 6).

[0072] Thereafter, the control device 10, for example, x and the amount of NO calculated in S25 x The amount of ammonia gas G2 required to reduce the total amount of ammonia and ammonium is calculated as the supply amount of ammonia gas G2 (reducing agent) to the second position (hereinafter also referred to as the second supply amount) (step S26 in FIG. 6).

[0073] Then, the control device 10 controls the opening and closing of at least one of the valves V1 and V2 so that the first supply amount of ammonia gas G2 (auxiliary fuel) calculated in step S21 is supplied to the incinerator 1, and the second supply amount of ammonia gas G2 (reducing agent) calculated in step S26 is supplied to the pipe L1 (step S27 in Figure 6).

[0074] That is, in S13, the control device 10 performs control to open or close at least one of the valves V1 and V2 based on, for example, the first supply amount identified in step S21 and the second supply amount calculated in step S26.

[0075] [Supply Control in the First Modification] Next, supply control in the first modified example will be explained. Figure 7 is a diagram explaining a specific example of supply control in the first modified example. Specifically, Figure 7 is a diagram explaining an example of the configuration of the incineration system 100 in the first modified example.

[0076] 7, the pipe L4 may be in communication with, for example, a position above the position where sludge incineration is performed in the incinerator 1 (for example, above the freeboard layer in the incinerator 1). In other words, the pipe L4 may be in communication with, for example, a position within the incinerator 1 through which the exhaust gas G1 flows after complete combustion. A portion of the ammonia gas G2 stored in the ammonia storage tank 2 may be supplied to, for example, a position above the position where sludge incineration is performed in the incinerator 1 via a portion of the pipe L3 and the pipe L4.

[0077] That is, a portion of the ammonia gas G2 stored in the ammonia storage tank 2 may be supplied to the incinerator 1, for example, as long as it is supplied to the exhaust gas G1 after complete combustion.

[0078] As a result, in the incineration system 100 of this modification, similar to the incineration system 100 of the first embodiment, for example, the amount of N2O emitted from the incinerator 1 and the amount of NO emitted from the incinerator 1 can be calculated. x This will make it possible to reduce both carbon dioxide emissions and CO2 emissions.

[0079] [Incineration system 200 according to the second embodiment] Next, an incineration system 200 according to the second embodiment will be described. Figure 8 is a diagram illustrating an example of the configuration of the incineration system 200 according to the second embodiment.

[0080] The control device 10 in this embodiment differs from the control device 10 in the first embodiment in that, for example, depending on the sludge supply situation to the incinerator 1, it controls at least one of the supply of ammonia gas G2 (auxiliary fuel) to a position (first position) where sludge is incinerated in the incinerator 1, and the supply of ammonia gas G2 (reducing agent) to a position (second position) within the pipe L1.

[0081] Specifically, for example, when the amount of sludge supplied to the incinerator 1 (e.g., the amount of sludge supplied per unit time) is equal to or greater than a predetermined threshold value (hereinafter also referred to as the third threshold value), the control device 10 controls the supply unit 20 so that at least one of the following is performed: a decrease in the amount of ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1; or an increase in the amount of ammonia gas G2 (reducing agent) supplied to the pipe L1.

[0082] That is, when the amount of sludge supplied to the incinerator 1 is equal to or greater than the third threshold, it can be determined that, for example, there is a sufficient amount of heat in the incinerator 1 and it is possible to sufficiently suppress the amount of N2O contained in the exhaust gas G1 discharged from the incinerator 1. Therefore, in this case, the control device 10 controls the supply unit 20, for example, to reduce the amount of ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1. Specifically, in this case, the control device 10 reduces the amount of ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1 by, for example, controlling the valve V1 to be smaller. Note that the control device 10 may also control the supply unit 20 in this case to stop the supply of ammonia gas G2 (auxiliary fuel) to the incinerator 1.

[0083] In addition, the case where the amount of sludge supplied to the incinerator 1 is equal to or greater than the third threshold value is, for example, when NO 2 contained in the exhaust gas G1 discharged from the incinerator 1 is xIt can be determined that there is a possibility that the amount of ammonia gas G2 (reducing agent) supplied to the pipe L1 (exhaust gas G1 flowing through the pipe L1) is increasing. Therefore, in this case, the control device 10 controls the supply unit 20 so as to increase the supply amount of ammonia gas G2 (reducing agent) supplied to the pipe L1, for example. Specifically, in this case, the control device 10 increases the supply amount of ammonia gas G2 (reducing agent) supplied to the pipe L1 by controlling the valve V2 to increase the opening degree, for example.

[0084] In addition, for example, when the amount of sludge supplied to the incinerator 1 (for example, the amount of sludge supplied per unit time) is less than a predetermined threshold value that is smaller than the third threshold value (hereinafter also referred to as the fourth threshold value), the control device 10 controls the supply unit 20 so that at least one of an increase in the amount of ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1 and a decrease in the amount of ammonia gas G2 (reducing agent) supplied to the pipe L1 is performed.

[0085] That is, when the amount of sludge supplied to the incinerator 1 is less than the fourth threshold, it can be determined that, for example, the amount of heat in the incinerator 1 is insufficient and the amount of N2O contained in the exhaust gas G1 discharged from the incinerator 1 cannot be sufficiently suppressed. Therefore, in this case, the control device 10 controls the supply unit 20 so as to increase the amount of ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1. Specifically, in this case, the control device 10 increases the amount of ammonia gas G2 (auxiliary fuel) supplied to the incinerator 1 by, for example, controlling the valve V1 to increase the opening degree.

[0086] In addition, the case where the amount of sludge supplied to the incinerator 1 is less than the fourth threshold value is, for example, when NO 2 contained in the exhaust gas G1 discharged from the incinerator 1 is less than the fourth threshold value. xIt can be determined that this is a case where there is a possibility that the amount of ammonia gas G2 (reducing agent) being supplied to the pipe L1 (exhaust gas G1 flowing through the pipe L1) is decreasing. Therefore, in this case, the control device 10 controls the supply unit 20, for example, to reduce the supply amount of ammonia gas G2 (reducing agent) supplied to the pipe L1. Specifically, in this case, the control device 10 reduces the supply amount of ammonia gas G2 (reducing agent) being supplied to the pipe L1, for example, by performing control to reduce the opening degree of the valve V2. Note that in this case, the control device 10 may also control the supply unit 20, for example, to stop the supply of ammonia gas G2 (reducing agent) to the pipe L1.

[0087] As a result, in the incineration system 200 of this embodiment, similar to the incineration system 100 of the first embodiment, for example, the amount of N2O emitted from the incinerator 1 and the amount of NO x This will make it possible to reduce both carbon dioxide emissions and CO2 emissions.

[0088] In addition, the control device 10 may control the supply unit 20 so that, for example, when the amount of sludge supplied to the incinerator 1 is less than a third threshold, at least one of increasing the amount of ammonia gas G2 (auxiliary fuel) to the incinerator 1 and decreasing the amount of ammonia gas G2 (reducing agent) to the pipe L1 is performed.

[0089] In addition, the control device 10 may be configured to stop the supply of ammonia gas G2 (auxiliary fuel) to the incinerator 1, for example, when the moisture content of the sludge supplied to the incinerator 1 is below a predetermined threshold value, regardless of the amount of sludge supplied to the incinerator 1.

[0090] [Supply Control in the Second Embodiment] Next, supply control in the second embodiment will be described with reference to a flow chart of FIG.

[0091] The control device 10 waits, for example, until a first timing occurs. The first timing may be a regular timing, for example, every minute.

[0092] Then, for example, when the first timing arrives, the control device 10 determines whether or not the state of sludge supply to the incinerator 1 satisfies a predetermined condition (hereinafter also referred to as the second condition) as shown in Fig. 9 (step S31 in Fig. 9). The second condition is, for example, that the amount of sludge supplied to the incinerator 1 (for example, the amount supplied per unit time) is equal to or greater than a third threshold, or that the amount of sludge supplied to the incinerator 1 (for example, the amount supplied per unit time) is less than a fourth threshold.

[0093] Specifically, the control device 10 acquires the supply amount of sludge measured by, for example, a flow meter (not shown) provided in the pipe L11, and determines whether or not the acquired supply amount satisfies the second condition.

[0094] As a result, when it is determined in step S31 that the supply state of sludge to the incinerator 1 satisfies the second condition (YES in step S32 in FIG. 9), the control device 10 controls, for example, the supply unit 20 (step S33 in FIG. 9).

[0095] On the other hand, if it is determined in step S31 that the state of sludge supply to the incinerator 1 does not satisfy the second condition (NO in step S32 in FIG. 9), the control device 10 may not perform step S33, for example.

[0096] The control device 10 may perform supply control by, for example, referring to the incineration temperature of the material to be incinerated in the incinerator 1 in addition to the supply status of sludge to the incinerator 1. In step S33, the control device 10 may perform control similar to that in step S13 described with reference to FIG. 6, etc.

[0097] Thus, in the incineration system 100 of this embodiment, the control device 10 controls, for example, at least one of the supply of ammonia gas G2 to the first position and the supply of ammonia gas G2 to the second position. Specifically, the control device 10 controls, for example, at least one of the supply of ammonia gas G2 to the first position and the supply of ammonia gas G2 to the second position depending on the supply status of the material to be incinerated to the incinerator 1.

[0098] As a result, in the incineration system 200 of this embodiment, similar to the incineration system 100 of the first embodiment, for example, the amount of N2O emitted from the incinerator 1 and the amount of NO x This will make it possible to reduce both carbon dioxide emissions and CO2 emissions.

[0099] The control device 10 may calculate the amount of heat generated by the incineration of the sludge supplied to the incinerator 1, for example, by using the composition of the sludge supplied to the incinerator 1 in addition to the amount of sludge supplied to the incinerator 1. The control device 10 may then determine the state of sludge supply to the incinerator 1, for example, by using the calculated amount of heat.

[0100] Furthermore, the supply control in this embodiment may be performed in the incineration system 100 in the first modified example, for example. [Explanation of symbols]

[0101] 1: Incinerator 2: Ammonia storage tank 3: Vaporizer 10: Control device 20: Supply section 100: Incineration system 101:CPU 102:Memory 103: Communication device 104: Storage medium 105: Bus 110: Program 130: Information storage area 200: Incineration system B1: Blower G1: Exhaust gas G2: Ammonia gas L1: Piping L2: Piping L3: Piping L4: Piping L11: Piping L21: Piping P1: Pressure regulator P2: Pressure regulator T1: Thermometer V1: Valve V2: Valve

Claims

1. an incinerator for incinerating materials to be incinerated; An incineration system comprising: a supply unit that supplies ammonia to each of a first position within the incinerator where the incineration of the material to be incinerated is carried out and a second position through which gas generated by the incineration of the material to be incinerated flows.

2. a control device that controls at least one of the supply of the ammonia to the first position and the supply of the ammonia to the second position; 2. The incineration system according to claim 1, wherein the control device controls at least one of the supply of ammonia to the first position and the supply of ammonia to the second position depending on the incineration status in the incinerator.

3. 3. The incineration system of claim 2, wherein when the incineration temperature of the material to be incinerated in the incinerator becomes equal to or higher than a first threshold, the control device performs at least one of control to reduce the amount of ammonia supplied to the first position and control to increase the amount of ammonia supplied to the second position.

4. The incineration system described in claim 2, wherein the control device performs at least one of control to increase the amount of ammonia supplied to the first position and control to decrease the amount of ammonia supplied to the second position when the incineration temperature of the material to be incinerated in the incinerator becomes lower than a first threshold value or a second threshold value lower than the first threshold value.

5. a control device that controls at least one of the supply of the ammonia to the first position and the supply of the ammonia to the second position; The incineration system according to claim 1, wherein the control device controls at least one of the supply of ammonia to the first position and the supply of ammonia to the second position depending on the supply status of the material to be incinerated to the incinerator.

6. A supply control method for an incineration system comprising: an incinerator for incinerating materials to be incinerated; and a supply unit for supplying ammonia to a first position in the incinerator where the materials to be incinerated are incinerated, and a second position through which gas generated by the incineration of the materials to be incinerated flows, A supply control method for controlling at least one of the supply of ammonia to the first position and the supply of ammonia to the second position depending on the incineration status in the incinerator.

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