JP7841808B2 - Incineration system - Google Patents

Description

This invention relates to an incineration system.

For example, a technology has been proposed that utilizes waste heat from an incinerator that burns sewage sludge (hereinafter also simply referred to as sludge or treated material) to induce exhaust gas from the incinerator (see Patent Document 1).

Japanese Patent Publication No. 2015-194307

In incineration systems that utilize waste heat from incinerators as described above, it is desirable to appropriately control the internal pressure of the incinerator, even when, for example, the amount of waste heat discharged from the incinerator changes.

The incineration system of the present invention comprises an incinerator for incinerating materials to be processed; a first supercharger having a first compressor for drawing in exhaust gas discharged from the incinerator and a first turbine for driving the first compressor; a blower for drawing in and blowing the exhaust gas; and a supply unit capable of supplying the exhaust gas blown from the blower to at least one of the first compressor and the chimney, supplying the air supplied to the incinerator to a heat exchanger that raises the temperature of the air supplied to the incinerator using the waste heat of the incinerator, and supplying a portion of the heated gas raised by the heat exchanger to at least one of the first turbine and the chimney.

The incineration system of this invention makes it possible to appropriately control the internal pressure of the incinerator.

Figure 1 is a diagram illustrating an example of the configuration of the incineration system 100 in the first embodiment. Figure 2 is a diagram illustrating a detailed configuration example of a part of the incineration system 100 in the first embodiment. Figure 3 illustrates the control of the internal pressure of the incinerator 1. Figure 4 illustrates the control of the internal pressure in the incinerator 1. Figure 5 illustrates the control of the internal pressure of the incinerator 1. Figure 6 illustrates a specific example of incinerator 1's internal pressure control. Figure 7 illustrates a specific example of furnace pressure control in incinerator 1. Figure 8 illustrates a specific example of incinerator 1's internal pressure control. Figure 9 illustrates a specific example of incinerator 1 internal pressure control. Figure 10 illustrates a specific example of furnace pressure control in incinerator 1. Figure 11 illustrates a specific example of furnace pressure control in incinerator 1. Figure 12 illustrates a specific example of pressure control within the incinerator 1. Figure 13 illustrates a specific example of pressure control within the incinerator 1. Figure 14 is a diagram illustrating an example of the configuration of the incineration system 200 in the second embodiment. Figure 15 illustrates a specific example of opening and closing control of valves V6 and V31. Figure 16 is a diagram illustrating an example of the configuration of the incineration system 300 in the third embodiment. Figure 17 illustrates the stopping of the supercharger 6.

The embodiments of the present invention will be described below with reference to the drawings. However, these embodiments do not limit the technical scope of the present invention.

[Incineration system 100 in the first embodiment]
First, the incineration system 100 in the first embodiment will be described. Figure 1 is a diagram illustrating an example of the configuration of the incineration system 100 in the first embodiment. Figure 2 is a diagram illustrating a detailed example of a part of the incineration system 100 in the first embodiment. Note that the arrangement and number of lines (piping) and valves shown below are examples only and are not limited to these.

As shown in Figure 1, the incineration system 100 includes, for example, an incinerator 1, a heat exchanger 2, a dust collector 3, a smoke scrubbing tower 4, a chimney 5, a turbocharger 6 (hereinafter also referred to as the first turbocharger 6 or induced turbocharger 6), a turbocharger 7 (hereinafter also referred to as the second turbocharger 7 or fluidized supercharger 7), a blower B1, and a blower B2. Blower B1 and blower B2 are, for example, devices that have the function of blowing air, such as fans or blowers.

The incinerator 1 is a fluidized bed incinerator that incinerates sludge (dewatered cake) supplied via line L41, and has a so-called fluidized bed 1a. Line L41 is, for example, piping connecting the incinerator 1 to upstream equipment (e.g., a sludge dryer not shown). The following description will assume that the incinerator 1 is a fluidized bed incinerator, but the incinerator 1 may be various other types of incinerators. Furthermore, the air supplied to the incinerator 1 will also be referred to as combustion air.

The supercharger 7 includes, for example, a compressor 7a (hereinafter also referred to as the second compressor 7a) and a turbine 7b (hereinafter also referred to as the second turbine 7b) connected via a rotating shaft 7c.

The blower B1 supplies air to the compressor 7a, for example, via line L14. Line L14 is, for example, piping connecting the outlet side (secondary side) of the blower B1 and the inlet side (primary side) of the compressor 7a. The configuration surrounding the supercharger 7 will be described below.

As shown in Figure 2, the compressor 7a compresses air supplied from the blower B1 via line L14 or air supplied via line L51 (outside air). Line L51 is a pipe that communicates with the area between the downstream outlet of the blower B1 and the upstream inlet of the compressor 7a in line L14, and is capable of supplying air (outside air) to the inlet side of the compressor 7a. Specifically, in the incineration system 100, air (outside air) is supplied to the compressor 7a by controlling the opening of valve V21 provided in line L51 (controlling the valve opening). In the example shown in Figure 1, line L51 communicates with line L14 upstream of the connection point between line L14 and line L52 (in other words, the point where line L52 branches off from line L14). Hereafter, the air compressed by the compressor 7a will also be referred to as compressed gas.

The compressor 7a then supplies compressed gas to the heat exchanger 2, for example, via line L11. Line L11 is, for example, a pipe connecting the outlet side of the compressor 7a to the air inlet side of the heat exchanger 2.

The heat exchanger 2 performs heat exchange between, for example, the exhaust gas G1 (hereinafter also referred to as the first exhaust gas G1) discharged from the incinerator 1 and the air supplied via line L11.

Specifically, the heat exchanger 2 uses, for example, the heat contained in the exhaust gas G1 supplied from the incinerator 1 via line L1 (i.e., the waste heat from the incinerator 1) to heat the air supplied via line L11 (for example, compressed gas supplied from the compressor 7a), and then supplies the heated air to the turbine 7b via line L12. Line L12 is, for example, a pipe connecting the air outlet side of the heat exchanger 2 to the inlet side of the turbine 7b. Hereinafter, the air heated by the heat exchanger 2 will also be referred to as heated gas G3.

The turbine 7b rotates its rotating shaft 7c using, for example, the energy (thermal energy) of the heated gas G3 supplied from the heat exchanger 2. The compressor 7a generates compressed gas by being driven in conjunction with the rotation of the rotating shaft 7c by the turbine 7b, and supplies the generated compressed gas to the heat exchanger 2.

The turbine 7b then supplies the heated gas G3 as combustion air to the incinerator 1 (the fluidized bed 1a in the incinerator 1) via, for example, line L13. Line L13 is, for example, a pipe connecting the outlet side of the turbine 7b to the air inlet side of the incinerator 1.

Furthermore, a line L52 is provided between line L14 and line L11. Line L52 is a pipe connecting, for example, the section between the downstream outlet of the blower B1 and the upstream inlet of the compressor 7a in line L14, and the section between the downstream outlet of the compressor 7a and the upstream air inlet of the heat exchanger 2 in line L11. Specifically, in the incineration system 100, for example, by controlling the opening of a valve V22 provided in line L52, air supplied from the blower B1 via line L14 or air supplied via line L51 (outside air) is directly supplied to the heat exchanger 2.

In other words, line L52 is piping used when, for example, air supplied from blower B1 via line L14 or air supplied via line L51 (outside air) is directly supplied to the heat exchanger 2 without passing through compressor 7a (bypassing compressor 7a).

Furthermore, between line L12 and line L13, for example, line L53 and bypass L15 are provided. Line L53 and bypass L15 are piping that connects the section of line L12 between the downstream side of the air outlet in the heat exchanger 2 and the upstream side of the inlet of the turbine 7b, and the section of line L13 between the downstream side of the outlet of the turbine 7b and the air inlet of the incinerator 1. In the example shown in Figure 1, bypass L15 connects to lines L12 and L13 at a point closer to the turbine 7b than line L53; however, bypass L15 may also connect to lines L12 and L13 at a point further from the turbine 7b than line L53. Line L53 and bypass L15, for example, supply the heated gas G3 supplied from the heat exchanger 2 directly to the incinerator 1, bypassing the turbine 7b.

In other words, line L53 is a piping used, for example, to directly supply the heated gas G3 supplied from the heat exchanger 2 to the incinerator 1 without passing through the turbine 7b (bypassing the turbine 7b). Specifically, in the incineration system 100, for example, by controlling the opening of valve V23 provided in line L53, the heated gas G3 supplied from the heat exchanger 2 is directly supplied to the incinerator 1 as combustion air.

Furthermore, the bypass L15 is a piping used, for example, to adjust the amount of heated gas G3 supplied from the heat exchanger 2 to the turbine 7b. Specifically, in the incineration system 100, for example, by controlling the opening and closing of the valve V10 provided in the bypass L15 (controlling the valve opening), a portion of the heated gas G3 supplied from the heat exchanger 2 is controlled to pass through the bypass L15, thereby adjusting the amount of heated gas G3 supplied from the heat exchanger 2 to the turbine 7b.

Furthermore, the capacity of valve V10 installed in bypass L15 may be smaller than, for example, the capacity of valve V23 installed in line L53 or valve V22 installed in line L52. In the incineration system 100, for example, by reducing the capacity of valve V10, it becomes possible to adjust the supply amount of the heated gas G3 supplied from the heat exchanger 2 to the turbine 7b with high precision.

Furthermore, between line L14 and line L13, a line L54 is provided, for example, to directly supply air supplied from blower B1 via line L14 to the incinerator 1. Line L54 connects, for example, the point between the downstream outlet of blower B1 and the upstream inlet of compressor 7a in line L14, and the point between the downstream outlet of turbine 7b and the upstream air inlet of incinerator 1 in line L13. Specifically, in the incineration system 100, for example, by controlling the opening of valve V24 provided in line L54, air supplied from blower B1 via line L14 is directly supplied to the incinerator 1. In the example shown in Figure 2, line L54 communicates with the area between the downstream side of the connection point between line L14 and line L51 (in other words, the point where line L51 merges with line L14) and the upstream side of the connection point between line L14 and line L52 (in other words, the point where line L52 branches off from line L14). Furthermore, it communicates with the downstream side of the connection point between line L13 and line L53 (in other words, the point where line L53 merges with line L13).

In other words, line L54 is a piping used, for example, when supplying air from blower B1 via line L14 directly to the incinerator 1 without passing through both the supercharger 7 and the heat exchanger 2 (bypassing the supercharger 7 and the heat exchanger 2).

Returning to Figure 1, the dust collector 3 is installed, for example, downstream of the heat exchanger 2 and removes impurities from the exhaust gas G1 supplied from the heat exchanger 2 via line L2. Line L2 is, for example, piping connecting the outlet side of the exhaust gas G1 from the heat exchanger 2 to the inlet side of the dust collector 3. The incineration system 100 may also include, for example, a cooling tower (not shown) upstream of the dust collector 3 to cool the exhaust gas G1 supplied from the heat exchanger 2.

The scrubbing tower 4 is, for example, located downstream of the dust collector 3. Exhaust gas G1 supplied from the dust collector 3 via line L3 is introduced from the bottom of the tower and brought into contact with scrubbing water sprayed from a water spray nozzle (not shown) at the top, thereby removing components such as _SOx from the exhaust gas G1 by incorporating them into the scrubbing water. Line L3 is, for example, piping that connects the outlet side of the dust collector 3 to the inlet side of the exhaust gas G1 in the scrubbing tower 4.

The chimney 5 is installed, for example, at the top of the smoke scrubbing tower 4. The chimney 5 then discharges, for example, the exhaust gas G2 (hereinafter also referred to as the second exhaust gas G2) that has been cleaned in the smoke scrubbing tower 4 to the outside.

Blower B2 is, for example, an induced draft fan that draws in exhaust gas G1 discharged from the incinerator 1. Specifically, blower B2 draws in exhaust gas G1 (exhaust gas G2) via lines L1, L2, L3, and L21. Line L21 is, for example, a pipe connecting the outlet side of exhaust gas G2 from the scrubbing tower 4 to the inlet side of blower B2. Blower B2 then supplies the exhaust gas G2 supplied from the scrubbing tower 4 via line L21 to the chimney 5 or turbocharger 6.

The supercharger 6 includes, for example, a compressor 6a (hereinafter also referred to as the first compressor 6a) and a turbine 6b (hereinafter also referred to as the first turbine 6b) connected via a rotating shaft 6c.

The compressor 6a compresses exhaust gas G2 supplied from the blower B2 via line L22, for example. The compressor 6a also compresses exhaust gas G2 supplied directly from the scrub tower 4 via line L24, for example. Line L22 is, for example, piping that connects the outlet side of the blower B2 and the inlet side of the compressor 6a. Specifically, line L22 supplies exhaust gas G2 supplied from the blower B2 to the compressor 6a by, for example, controlling the opening of a valve V2 provided in line L22. Line L24 is, for example, piping that connects the point between the downstream side of the outlet of the scrub tower 4 and the upstream side of the inlet of the blower B2 in line L21, and the point between the downstream side of the outlet of the blower B2 and the upstream side of the inlet of the compressor 6a in line L22. In other words, line L24 is piping used, for example, to supply exhaust gas G2 from the scrubbing tower 4 directly to the compressor 6a, bypassing the blower B2. Specifically, in the incineration system 100, for example, by controlling the opening of valve V4 provided in line L24, exhaust gas G2 supplied from the scrubbing tower 4 is supplied directly to the compressor 6a.

Furthermore, the compressor 6a compresses air (outside air) supplied via line L25, for example. Line L25 is a pipe that communicates with a point between the downstream outlet of blower B2 in line L22 and the upstream inlet of compressor 6a, and is capable of supplying air (outside air) to the inlet side of compressor 6a. Specifically, in the incineration system 100, air (outside air) is supplied to the compressor 6a by controlling the opening of a valve V3 provided in line L25, for example. In the example shown in Figure 1, line L25 communicates with a point between the upstream inlet of compressor 6a and the downstream side of the connection point between line L22 and line L29 (in other words, the point where line L29 branches off from line L22). Furthermore, line L29 is a pipe that connects, for example, the area between the downstream outlet of blower B2 and the upstream inlet of compressor 6a to the inlet of chimney 5. In other words, line L29 is a pipe used, for example, when exhaust gas G2 supplied from the scrubbing tower 4 (blower B2) is directly supplied to chimney 5, bypassing the turbocharger 6. Specifically, in the incineration system 100, for example, by controlling the opening of valve V1 provided in line L29, exhaust gas G2 supplied from the scrubbing tower 4 (blower B2) is directly supplied to chimney 5. Hereinafter, the air or exhaust gas G2 compressed by compressor 6a will also be referred to as compressed gas.

The compressor 6a then supplies compressed gas to the chimney 5, for example, via line L30. Line L30 is, for example, a pipe connecting the outlet side of the compressor 6a to the inlet side of the chimney 5. Specifically, in the incineration system 100, compressed gas is supplied to the chimney 5 by, for example, controlling the opening of valve V9 provided in line L30.

The turbine 6b rotates its rotating shaft 6c using the energy (thermal energy) of the air (heated gas G3) supplied from the heat exchanger 2 via line L26. Line L26 is, for example, a pipe connecting the section between the downstream outlet of the heat exchanger 2 and the turbine 7b in line L12 to the turbine 6b. Specifically, in the incineration system 100, the heated gas G3 supplied from the heat exchanger 2 via line L12 is supplied to the turbine 6b by controlling the opening of a valve V5 provided in line L26. In the example shown in Figure 2, line L26 communicates with line L12 upstream of the connection point between line L12 and line L53 (in other words, the point where line L53 branches off from line L12). The compressor 6a compresses air or exhaust gas G2 by being driven in conjunction with the rotation of the rotating shaft 6c by the turbine 6b.

The turbine 6b then supplies heated gas G3 to the chimney 5, for example, via line L23. Line L23 is, for example, a pipe connecting the outlet side of the turbine 6b to the inlet side of the chimney 5.

Furthermore, between line L26 and line L23, for example, line L27 and bypass L28 are provided. Line L27 and bypass L28 are, for example, pipes connecting the downstream side of the connection point with line L12 in line L26 and the upstream side of the turbine 6b inlet, and the downstream side of the turbine 6b outlet in line L23 and the inlet side of the chimney 5. Line L27 and bypass L28, for example, supply exhaust gas G2 from the heat exchanger 2 directly to the chimney 5, bypassing the turbine 6b.

In other words, line L27 is a piping used, for example, when the heated gas G3 supplied from the heat exchanger 2 via line L26 is directly supplied to the chimney 5, bypassing the turbine 6b. Specifically, in the incineration system 100, for example, by controlling the opening of valve V7 provided in line L27, the heated gas G3 supplied from the heat exchanger 2 via line L26 is directly supplied to the chimney 5.

Furthermore, the bypass L28 is a pipe used, for example, to adjust the amount of heated gas G3 supplied from the heat exchanger 2 via line L26 to the turbine 6b. Specifically, in the incineration system 100, for example, by controlling the opening and closing of valve V6 provided in the bypass L28, a portion of the heated gas G3 supplied from the heat exchanger 2 via line L26 is controlled to pass through the bypass L28, thereby adjusting the amount of heated gas G3 supplied from the heat exchanger 2 via line L26 to the turbine 6b.

Here, the capacity of valve V6 installed in bypass L28 may be smaller than, for example, the capacity of valve V7 installed in line L27. This allows the incineration system 100 to precisely adjust the supply amount of heated gas G3 supplied from the heat exchanger 2 via line L26 to the turbine 6b by adjusting the capacity of valve V6.

Furthermore, the incineration system 100 may, for example, install other heat exchangers (not shown) in line L23. These other heat exchangers may, for example, recover waste heat exceeding the thermal energy used in the white smoke prevention treatment at the chimney 5.

Furthermore, as shown in Figures 1 and 2 below, the section including lines L11, L12, L13, L14, bypass L15, L21, L22, L23, L24, L25, L26, L27, bypass L28, L29, L30, L51, L52, L53, L54, valves V1, V2, V3, V4, V5, V6, V7, V8, V9, V10, V21, V22, V23, and V24 is collectively referred to as the supply section 20.

In other words, the supply unit 20 can, for example, supply air supplied from the blower B1 or air taken in from the outside (outside air) to the compressor 7a, supply the compressed gas compressed by the compressor 7a to the heat exchanger 2, supply the heated gas G3 heated by the heat exchanger 2 to the turbine 7b, and supply the heated gas G3 discharged from the turbine 7b to the incinerator 1 as combustion air. The supply unit 20 can also, for example, supply the heated gas G3 heated by the heat exchanger 2 to the chimney 5. The supply unit 20 can also, for example, supply the heated gas G3 heated by the heat exchanger 2 to the turbine 6b, and supply the heated gas G3 discharged from the turbine 6b to the chimney 5. The supply unit 20 can also, for example, supply exhaust gas G2 supplied from the scrubbing tower 4 to the chimney 5 via the blower B2. Furthermore, the supply unit 20 can, for example, supply air (outside air) taken in from the outside to the compressor 6a, and supply the compressed gas compressed by the compressor 6a to the chimney 5. Also, the supply unit 20 can, for example, supply exhaust gas G2 supplied from the scrubbing tower 4 to the compressor 6a via the blower B2, and supply the compressed gas compressed by the compressor 6a to the chimney 5. Moreover, the supply unit 20 can, for example, supply exhaust gas G2 supplied from the scrubbing tower 4 to the compressor 6a by bypassing the blower B2, and supply the compressed gas compressed by the compressor 6a to the chimney 5.

Thus, the incineration system 100 in this embodiment includes, for example, an incinerator 1 for incinerating sludge (material to be treated), a supercharger 6 having a compressor 6a for drawing in exhaust gas G2 discharged from the incinerator 1 and a turbine 6b for driving the compressor 6a, and a supply unit 20 that supplies air supplied to the incinerator 1 to a heat exchanger 2 that raises the temperature using the waste heat of the incinerator 1, and can supply the heated gas G3 raised by the heat exchanger 2 to at least one of the turbine 6b and the chimney 5.

As a result, the incineration system 100 in this embodiment can, for example, control the operation of the turbocharger 6 and the blower B2, as described later, to ensure that the internal pressure of the incinerator 1 reaches the target pressure, even when the amount of waste heat in the exhaust gas G1 discharged from the incinerator 1 changes.

[Control of internal pressure in incinerator 1]
Next, we will explain the internal pressure control of incinerator 1. Figures 3 to 5 illustrate the internal pressure control of incinerator 1.

The following explains the technical reasons for implementing this furnace pressure control. The turbocharger 6 operates using, for example, the thermal energy of waste heat from the incinerator 1. Furthermore, the thermal energy of waste heat from the incinerator 1 changes due to various factors, such as changes in the amount of sludge to be incinerated and changes in the properties of the sludge. Therefore, the incineration system 100 controls the furnace pressure of the incinerator 1 in response to changes in the thermal energy of waste heat. Specifically, the incineration system 100 controls the furnace pressure of the incinerator 1 to be maintained at a predetermined target pressure.

As shown in Figures 3 and 4, the incineration system 100 includes, for example, a control device 10 that controls the internal pressure in the incinerator 1.

Specifically, the control device 10 controls the opening and closing of valves V1, V2, V3, V4, V5, V6, V7, V8, and V9. Furthermore, the control device 10 controls the starting and stopping of the blower B2. More specifically, the control device 10 performs these controls based on various measurements from instruments (e.g., thermometers, pressure gauges, and flow meters) installed in each line such as lines L22, L23, L26, and L30, and from rotational measuring instruments attached to the rotating shaft 6c.

The control device 10 is, for example, a computer having a CPU (Central Computing Unit) and memory. The control device 10 may also include, for example, a PIC (Peripheral Interface Controller). The control device 10 controls the internal pressure of the incinerator 1 through the cooperation of the CPU and a program stored in a storage medium (not shown).

Specifically, as shown in Figure 5, the control device 10 controls the internal pressure of the incinerator 1 according to the amount of waste heat recovered from the exhaust gas G1 in the heat exchanger 2. In other words, the control device 10 controls the internal pressure of the incinerator 1 according to the energy of the heated gas G3 supplied from the heat exchanger 2 to the turbine 6b via lines L12 and L26 (in other words, the amount of waste heat discharged from the incinerator 1).

Then, if the control device 10 determines, for example, from the measured values described above that the energy of the heating gas G3 supplied to the turbine 6b is sufficient to operate the turbocharger 6 (large waste heat amount in step S1 of Figure 5), it performs furnace pressure control of the incinerator 1 by inducing exhaust gas G2 with the turbocharger 6, without inducing exhaust gas G2 with the blower B2 (hereinafter also referred to as autonomous operation control or turbocharger autonomous operation control) (step S2 of Figure 5). The measured values referenced in the above determination are, for example, the flow rate of the heating gas G3 measured by the flow meter installed in the bypass L28, and the temperature of the heating gas G3 measured by the thermometer installed in line L26.

In other words, the control device 10 determines that, in this case, the internal pressure of the incinerator 1 can be controlled to reach the target pressure by only inducing exhaust gas G2 with the turbocharger 6, and selects to execute autonomous operation control.

Specifically, as shown in Figures 3 and 4, the control device 10, for example, controls the opening of valve V4 located in line L24, thereby supplying exhaust gas G2 from the scrubbing tower 4 to the turbocharger 6, bypassing the blower B2. Furthermore, the control device 10 controls the stopping of blower B2, for example, if blower B2 is running.

Furthermore, in this case, the control device 10 controls the internal pressure of the incinerator 1 by appropriately adjusting, for example, the opening degree of valve V6 provided in the bypass L28. Specifically, the control device 10, for example, refers to the measured value from a pressure gauge (not shown) installed inside the incinerator 1, and if it determines that the internal pressure of the incinerator 1 is lower than a predetermined target pressure, it increases the opening degree of valve V6 to reduce the amount of heat input to the turbine 6b (reduces the rotational speed of the compressor 6a), thereby controlling the amount of exhaust gas G2 induced by the turbocharger 6. This makes it possible for the control device 10 to increase the internal pressure of the incinerator 1, and to control the system so that the difference between the internal pressure of the incinerator 1 and the target pressure becomes smaller.

On the other hand, the control device 10, for example, refers to the measurement value from a pressure gauge installed inside the incinerator 1, and if it determines that the internal pressure of the incinerator 1 is higher than the target pressure, it controls the system by reducing the opening of valve V6 to increase the heat input to turbine 6b (increasing the rotational speed of compressor 6a), thereby increasing the amount of exhaust gas G2 induced by the turbocharger 6. This allows the control device 10 to, for example, lower the internal pressure of the incinerator 1, and control the system to reduce the difference between the internal pressure of the incinerator 1 and the target pressure.

Furthermore, in this case, the control device 10 controls the pressure on the outlet side of the compressor 6a by appropriately adjusting, for example, the opening degree of the valve V9 provided in line L30.

Returning to Figure 5, the control device 10, for example, if it determines from the measured values of various instruments such as thermometers installed in each line that the energy of the heating gas G3 supplied to the turbine 6b is insufficient to operate the turbocharger 6, and that the amount of exhaust gas G2 induced by the turbocharger 6 is insufficient (as shown in the waste heat amount in step S1 of Figure 5), then performs furnace pressure control of the incinerator 1 (hereinafter also referred to as assist operation control) by induced exhaust gas G2 by the blower B2 in addition to the induction of exhaust gas G2 by the turbocharger 6 (step S3 of Figure 5). The measured values referenced in the above determination are, for example, the flow rate of the heating gas G3 measured by the flow meter installed in the bypass L28, and the temperature of the heating gas G3 measured by the thermometer installed in line L26.

In other words, the control device 10 determines that, in this case, unless exhaust gas G2 is induced by both the turbocharger 6 and the blower B2, it cannot control the internal pressure of the incinerator 1 to reach the target pressure, and therefore selects to execute the assist operation control.

Specifically, as shown in Figures 3 and 4, the control device 10, for example, when the blower B2 is stopped, initiates the induction of exhaust gas G2 by the blower B2 by controlling its startup. Then, after controlling the startup of the blower B2, the control device 10 controls the closing of valve V4 located in line L24. Furthermore, if valve V2 is closed, the control device 10 controls its opening. Also, if valves V1 and V3 are open, the control device 10 controls their closing. Finally, if valve V7 is open, the control device 10 controls its closing in stages.

Furthermore, in this case, the control device 10 controls the rotational speed of the blower B2 using an inverter (not shown) according to the amount of exhaust gas G2 induced in the turbocharger 6.

Specifically, the control device 10, for example, refers to the measurement value from a pressure gauge installed inside the incinerator 1. If it determines that the internal pressure of the incinerator 1 is lower than the target pressure, it controls the blower B2 by reducing its rotational speed using an inverter, thereby reducing the amount of exhaust gas G2 drawn in by the blower B2. This allows the control device 10 to, for example, increase the internal pressure of the incinerator 1, and control the system to reduce the difference between the internal pressure of the incinerator 1 and the target pressure.

On the other hand, the control device 10, for example, refers to the measurement value from a pressure gauge installed inside the incinerator 1, and if it determines that the internal pressure of the incinerator 1 is higher than the target pressure, it controls the system by increasing the rotation speed of the blower B2 using an inverter, thereby increasing the amount of exhaust gas G2 induced by the blower B2. This allows the control device 10 to, for example, lower the internal pressure of the incinerator 1, and control the system to reduce the difference between the internal pressure of the incinerator 1 and the target pressure.

Returning to Figure 5, if the control device 10 determines, for example, from the measured values of various instruments such as thermometers installed in each line, that the energy of the heating gas G3 supplied to the turbine 6b is insufficient to operate the turbocharger 6 (small waste heat amount in step S1 of Figure 5), it will perform furnace pressure control of the incinerator 1 by inducing exhaust gas G2 with the blower B2 (hereinafter also referred to as offline operation control) without inducing exhaust gas G2 with the turbocharger 6 (step S4 of Figure 5).

In other words, the control device 10 determines that, in this case, it is necessary to control the incinerator 1 so that the internal pressure reaches the target pressure by only inducing exhaust gas G2 with the blower B2, and selects to execute offline operation control.

Specifically, as shown in Figures 3 and 4, the control device 10, for example, stops the induction of exhaust gas G2 by the turbocharger 6 by controlling its shutdown when the turbocharger 6 is running. Furthermore, the control device 10 controls the opening of valve V7 when it is closed, for example. Also, the control device 10 controls the opening of valves V1 and V3 when they are closed, for example. Finally, the control device 10 controls the closing of valve V2 when it is open, for example.

Thus, the incineration system 100 in this embodiment includes, for example, a control device 10 that controls the supply unit 20. The control device 10, by controlling the supply unit 20, appropriately switches between autonomous operation control, assisted operation control, and offline operation control.

As a result, the incineration system 100 in this embodiment can control the internal pressure of the incinerator 1 to reach the target pressure, even when, for example, the amount of waste heat in the exhaust gas G1 discharged from the incinerator 1 changes.

Here, during the execution of autonomous operation control, if, for example, the amount of waste heat in the exhaust gas G1 discharged from the incinerator 1 decreases, and the energy of the heated gas G3 supplied from the heat exchanger 2 via line L26 decreases, the control device 10 controls the opening of valve V6 provided in the bypass L28 to gradually reduce the amount of heated gas G3 passing through the bypass L28, thereby suppressing the decrease in the amount of heated gas G3 (amount of thermal energy of heated gas G3) supplied to the turbine 6b. Then, for example, if the energy of the heated gas G3 supplied from the heat exchanger 2 decreases further after the opening of valve V6 has reached its minimum (for example, 0), the control device 10 controls the start of the blower B2 in order to switch from autonomous operation control to assisted operation control.

However, for example, if it takes time to start up the blower B2, the incineration system 100 may not switch quickly from autonomous operation control to assisted operation control, which may temporarily reduce the accuracy of the internal pressure control in the incinerator 1.

Therefore, the control device 10 may, for example, refer to a flow meter (not shown) that measures the flow rate of the heating gas G3 flowing through the bypass L28, and acquire the flow rate of the heating gas G3 flowing through the bypass L28 (hereinafter also referred to as the first flow rate). Then, if the control device 10 determines, for example, that the acquired first flow rate satisfies predetermined conditions, it may initiate switching to assist operation control by adjusting the amount of exhaust gas G2 supplied from the blower B2 to the compressor 6a (for example, by starting the blower B2).

Specifically, the control device 10 may, for example, initiate switching to assist operation control when the first flow rate of the heating gas G3 flowing through the bypass L28 satisfies a predetermined condition (hereinafter also referred to as the first condition). The first condition is, for example, that the first flow rate of the heating gas G3 flowing through the bypass L28 falls below a predetermined threshold (hereinafter also referred to as the first threshold).

Furthermore, the control device 10 may, for example, in addition to acquiring the first flow rate, refer to a flow meter (not shown) that measures the flow rate of the heating gas G3 flowing through line L26, and acquire the flow rate of the heating gas G3 flowing through line L26 (hereinafter also referred to as the second flow rate). The control device 10 may, for example, initiate switching to assist operation control when the ratio of the first flow rate to the second flow rate satisfies a predetermined condition (hereinafter also referred to as the second condition). The second condition is, for example, that the ratio of the first flow rate to the second flow rate falls below a predetermined threshold (hereinafter also referred to as the second threshold).

In other words, the incineration system 100 in this embodiment may initiate switching to assist operation control at a timing prior to the point when the valve V6 opening degree becomes minimum due to a decrease in the energy of the heating gas G3 supplied from the heat exchanger 2 via line L26.

As a result, the incineration system 100 in this embodiment can complete the startup of the blower B2 before the opening degree of the valve V6 provided in the bypass L28 reaches its minimum, and can complete the switch to assisted operation control. Therefore, the incineration system 100 can smoothly switch from autonomous operation control to assisted operation control.

Furthermore, the control device 10 may, for example, initiate switching to assist operation control when the opening degree of valve V6 provided in the bypass L28 falls below a predetermined level.

Furthermore, the control device 10 may, for example, in addition to acquiring the first flow rate, refer to a flow meter (not shown) that measures the flow rate of exhaust gas G2 flowing through line L30, and acquire the flow rate of exhaust gas G2 flowing through line L30. The control device 10 may, for example, initiate switching to assist operation control when the ratio of the first flow rate to the flow rate of exhaust gas G2 flowing through line L30 satisfies a predetermined condition.

[Modified version of the incineration system 100 in the first embodiment]
Next, a modified example of the incineration system 100 in the first embodiment will be described.

The control device 10 may, during the execution of assisted operation control, refer to a pressure gauge (not shown) that measures the pressure in line L22 and acquire the pressure in line L22 (i.e., the inlet pressure of the compressor 6a). The control device 10 may then, for example, initiate a switch to independent operation control when the pressure in line L22 falls below a predetermined pressure, which is a condition for transitioning to independent operation. Specifically, in this case, the control device 10 may, for example, switch to independent operation control by opening valve V4 and then stopping the blower B2.

In other words, after switching from assisted operation control to autonomous operation control, if the amount of waste heat from the incinerator 1 increases and the rotational speed of the compressor 6a in the supercharger 6 increases, the amount of compressed gas generated by the compressor 6a increases, and the pressure on the inlet side of the compressor 6a (for example, the pressure in line L22) becomes the predetermined pressure. Therefore, the control device 10 in this embodiment may, for example, switch from assisted operation control to autonomous operation control by performing valve opening control and blower B2 stopping control in response to the pressure in line L22 becoming the predetermined pressure.

This enables the incineration system 100 in this embodiment to smoothly switch from assisted operation control to autonomous operation control.

Furthermore, the incineration system 100 can prevent exhaust gas G2 that has passed through the stopped blower B2 from being supplied to the compressor 6a by, for example, controlling the opening of valve V4 when switching from assisted operation control to autonomous operation control. Therefore, the incineration system 100 can prevent a decrease in the supply efficiency of exhaust gas G2 due to air resistance generated in the blower B2 (for example, the fan in blower B2), and can prevent a decrease in energy efficiency when switching from assisted operation control to autonomous operation control.

[Modification of the incineration system 100 in the first embodiment (2)]
Next, other modifications of the incineration system 100 in the first embodiment will be described.

The control device 10 may, for example, control the opening of the valve V6 provided in the bypass L28 so that a portion of the heating gas G3 supplied from the heat exchanger 2 (for example, a certain amount of heating gas G3) is supplied to the bypass L28 when switching from autonomous operation control to assisted operation control.

In other words, immediately after switching from autonomous operation control to assisted operation control, the pressure in line L22 may fall below a predetermined pressure, which is the condition for transitioning to autonomous operation. Specifically, for example, if the amount of waste heat temporarily increases due to a change in sludge properties, and the rotational speed of the compressor 6a in the turbocharger 6 increases, the pressure in line L22 will reach the predetermined pressure. When the pressure in line L22 reaches this predetermined pressure, the incineration system 100 will switch back from assisted operation control to autonomous operation control, even immediately after a switch from autonomous operation control to assisted operation control has occurred. As a result, the incineration system 100 will repeatedly switch between autonomous operation control and assisted operation control, potentially causing failure or deterioration of the blower B2.

Therefore, the control device 10 in this embodiment may, for example, adjust the supply amount of heated gas G3 that bypasses the turbine 6b and is supplied to the chimney 5 (the supply amount of heated gas G3 flowing through the bypass L28) according to the amount of exhaust gas G2 supplied from the blower B2 to the compressor 6a. Specifically, when switching from autonomous operation control to assisted operation control, the control device 10 may control the opening of a valve V6 provided in the bypass L28 so that a predetermined amount of heated gas G3 flows through the bypass L28.

As a result, in the incineration system 100 of this embodiment, when assist operation control is executed, for example, by reducing the heat input to the turbine 6b and lowering the rotation speed of the compressor 6a, it is possible to suppress the pressure in line L22 from reaching the predetermined pressure. Therefore, in the incineration system 100, for example, immediately after switching from autonomous operation control to assist operation control, it is possible to prevent the pressure in line L22 from reaching the predetermined pressure. Consequently, in the incineration system 100, for example, it is possible to prevent repeated switching between autonomous operation control and assist operation control, thereby preventing failure and deterioration of the blower B2.

[Specific example of incinerator 1 internal pressure control]
Next, we will explain a specific example of furnace pressure control in incinerator 1. Figures 6 to 14 illustrate a specific example of furnace pressure control in incinerator 1. The dashed lines in Figures 6 to 14 indicate that the valves provided on each line are closed.

First, we will explain the incineration system 100 at the start timing of the incinerator 1's internal pressure control (the start timing of the incineration system 100). Figure 6 is a diagram illustrating the incineration system 100 at the start timing of the incinerator 1's internal pressure control.

As shown in Figure 6, the control device 10, for example, controls the opening of valve V1 and controls the closing of valves V2, V3, V4, V5, V6, V7, V8, and V9. Then, the control device 10, for example, controls the start of the blower B2 and begins controlling the internal pressure of the incinerator 1.

Next, the control device 10, for example as shown in Figure 7, controls the opening of valves V22 and V23, and controls the closing of valves V10, V21, and V24. Then, the control device 10 controls the start of the blower B1 and begins controlling the supply of air to the incinerator 1. Specifically, the air supplied by the blower B1 is supplied to the incinerator 1 via a portion of line L14, line L22, a portion of line L11, a portion of line L12, line L53, and a portion of line L13, as shown in Figure 7.

Furthermore, the control device 10 initiates, for example, the feeding of fuel using a fuel gun (not shown) and the heating of the incinerator 1 using a heating burner (not shown). In addition, the control device 10 initiates the feeding of sludge into the incinerator 1 via line L41, for example, and begins the incineration of the sludge in the incinerator 1.

Subsequently, the exhaust gas G1 (exhaust gas G2) discharged from the incinerator 1 as a result of sludge incineration is supplied to the scrubbing tower 4 via lines L1, L2, and L3, as shown in Figure 6. It is then supplied to the chimney 5 via line L21, blower B2, part of line L22, and line L29, and discharged to the outside from the chimney 5.

Thus, the incineration system 100 in this embodiment includes, for example, a control device 10 that controls the supply unit 20. The control device 10, for example, controls the supply unit 20 to supply the exhaust gas G2 blown from the blower B2 to the chimney 5.

In other words, for example, when the incineration system 100 is started and the internal pressure control of the incinerator 1 is initiated, the control device 10 starts executing offline operation control by inducing exhaust gas G2 into the blower B2.

As a result, the control device 10 in this embodiment can start controlling the internal pressure of the incinerator 1 even when, for example, the amount of waste heat in the exhaust gas G1 discharged from the incinerator 1 is insufficient.

Next, we will explain the incineration system 100 at the start-up timing of the turbocharger 7. Figures 8 to 10 illustrate the incineration system 100 at the start-up timing of the turbocharger 7. Note that the start-up timing of the turbocharger 7 may be, for example, the timing when the temperature of the heating gas G3 flowing through line L26 rises to a predetermined temperature (hereinafter also referred to as the first temperature).

For example, if the control device 10 determines, based on measurements from various instruments installed in each line, that the temperature of the heating gas G3 flowing through line L26 has risen to the first temperature (the timing for starting the turbocharger 7 has arrived), the control device 10, as shown in Figure 8, controls the closing of valves V22 and V23 to supply air (heating gas G3) to the turbine 7b, thereby rotating the turbine 7b. Then, in this case, the compressor 7a begins drawing in air supplied from, for example, the blower B1.

Next, for example, if the control device 10 determines, based on measurements from various instruments installed in each line, that the temperature of the heating gas G3 flowing through line L26 is higher than the first temperature and has risen to a predetermined temperature (hereinafter also referred to as the second temperature), or if it determines that the inlet pressure of the compressor 7a has fallen below a predetermined pressure, the control device 10 will, as shown in Figure 9, for example, open valve V21 and stop blower B1. In other words, in this case, the control device 10 determines that the energy of the heating gas G3 supplied from the heat exchanger 2 is sufficient to operate the supercharger 7, and controls blower B1 to stop.

Subsequently, for example, if the control device 10 determines, based on measurements from various instruments installed in each line, that the temperature of the heating gas G3 flowing through line L26 is higher than the second temperature and has risen to a predetermined temperature (hereinafter also referred to as the third temperature), or if it determines that the inlet pressure of the compressor 7a has fallen below a predetermined pressure, the control device 10 will, for example, control the opening of valve V10, as shown in Figure 9. That is, in this case, the control device 10 determines that the energy of the heating gas G3 supplied from the heat exchanger 2 exceeds the energy required to operate the supercharger 7, and controls the system so that a portion of the energy of the heating gas G3 supplied from the heat exchanger 2 bypasses the turbine 7b.

Furthermore, for example, if the control device 10 determines, based on measurements from various instruments installed in each line, that the temperature of the heating gas G3 flowing through line L26 is higher than the third temperature and has risen to a predetermined temperature (hereinafter also referred to as the fourth temperature), or if it determines that the opening degree of valve V10 has reached a predetermined opening degree or greater, the control device 10 will, as shown in Figures 9 and 10, perform, for example, valve opening control of valves V5 and V7. That is, in this case, the control device 10 determines that it is now possible to operate not only the turbocharger 7 but also the turbocharger 6 using the energy of the heating gas G3 supplied from the heat exchanger 2, and controls the system so that a portion of the energy of the heating gas G3 supplied from the heat exchanger 2 is supplied to line L26.

Furthermore, the control device 10 may, for example, start adjusting the opening degree of valve V7 after controlling the opening of valve V5.

Thus, the incineration system 100 in this embodiment includes a supercharger 7 having, for example, a compressor 7a that compresses air to generate compressed gas and a turbine 7b that drives the compressor 7a. Furthermore, the supply unit 20 in this embodiment can, for example, supply compressed gas to the heat exchanger 2, supply the heated gas G3 heated by the heat exchanger 2 to the turbine 7b, and supply the heated gas G3 discharged from the turbine 7b to the incinerator 1. The control device 10 in this embodiment controls the supply unit 20 according to the amount of waste heat from the incinerator 1, and supplies a portion of the heated gas G3 supplied from the heat exchanger 2 to at least one of the turbine 6b and the chimney 5.

As a result, the control device 10 in this embodiment can, for example, start the turbocharger 7 in response to an increase in the amount of waste heat from the exhaust gas G1 discharged from the incinerator 1. Furthermore, the control device 10 in this embodiment can, for example, utilize a portion of the waste heat from the exhaust gas G1 discharged from the incinerator 1 to start the turbocharger 6. Therefore, the incineration system 100 in this embodiment can, for example, start both the turbocharger 6 and the turbocharger 7 using the energy of air (heat-boosting gas G3) supplied from a single heat exchanger (heat exchanger 2).

Furthermore, the control device 10 may, for example, continue to operate the blower B1 even when the temperature of the heating gas G3 flowing through line L26 reaches a second temperature or higher.

Furthermore, while the above example described a case where the temperature of the heated gas G3 flowing through line L26 is used to determine whether the turbocharger 7 has reached the start-up timing or other timings, this is not limited to this. The control device 10 may also use other indicators, such as the temperature of the exhaust gas in line L2, to determine whether the turbocharger 7 has reached the start-up timing or other timings.

Next, the incineration system 100 at the start-up timing of the turbocharger 6 will be explained. Figure 11 is a diagram illustrating the incineration system 100 at the start-up timing of the turbocharger 6. Note that the start-up timing of the turbocharger 6 may, for example, be the timing when the temperature of the heating gas G3 flowing through line L26 is higher than the fourth temperature and has risen to a predetermined temperature (hereinafter also referred to as the fifth temperature). Alternatively, the start-up timing of the turbocharger 6 may also be the timing when the flow rate of the heating gas G3 flowing through line L26 exceeds a predetermined flow rate.

The control device 10, for example, if it determines from the measured values of various instruments installed in each line that the temperature of the heating gas G3 flowing through line L26 has risen to the fifth temperature (the timing for starting the supercharger 6 has arrived), will, as shown in Figure 11, for example, control the opening of valve V9, and also control the opening of valves V3 and V8, thereby supplying the heating gas G3 to the turbine 6b and rotating the turbine 6b. Specifically, in this case, the air supplied by the blower B1 is supplied to the turbine 6b via, for example, line L51, part of line L14, compressor 7a, line L11, heat exchanger 2, part of line L12, and line L26, as shown in Figures 9 and 11. Then, the compressor 6a starts drawing in outside air (outside air) in conjunction with the opening control of valve V3.

Furthermore, in this case, the control device 10 adjusts the amount of heated gas G3 supplied to the turbine 6b by, for example, adjusting the opening degree of valve V6 as needed. In addition, in this case, the control device 10 adjusts the pressure on the outlet side of the compressor 6a by, for example, adjusting the opening degree of valve V9 as needed.

Furthermore, the control device 10 may, for example, perform the opening control of valve V3 and valve V8 in that order, and then begin adjusting the opening degrees of valves V6 and V9.

Thus, in this embodiment, the control device 10 controls the supply unit 20 according to the amount of waste heat from the incinerator 1, for example, and increases the amount of heated gas G3 supplied from the heat exchanger 2 to the turbine 6b.

As a result, the control device 10 in this embodiment can start the turbocharger 6 by using, for example, a portion of the waste heat from the exhaust gas G1 discharged from the incinerator 1.

Next, we will describe the incineration system 100 at the timing when the incinerator 1's internal pressure control is transitioned from offline operation control to assisted operation control (hereinafter also referred to as the first transition timing). Figure 12 is a diagram illustrating the incineration system 100 at the first transition timing. The first transition timing may, for example, be the timing when the temperature of the heating gas G3 flowing through line L26 is higher than the fifth temperature and has risen to a predetermined temperature (hereinafter also referred to as the sixth temperature). Furthermore, the first transition timing may also be the timing when the flow rate of the heating gas G3 flowing through line L26 exceeds a predetermined flow rate. Additionally, the first transition timing may also be the timing when the flow rate of the exhaust gas G2 flowing through line L30 exceeds a predetermined flow rate.

The control device 10, for example, if it determines from the measured values of various instruments installed in each line that the temperature of the heating gas G3 flowing through line L26 has risen to the sixth temperature (the first transition timing has been reached), will, as shown in Figure 12, for example, control the opening of valve V2 to supply the exhaust gas G2 blown from blower B2 to compressor 6a. Specifically, in this case, the exhaust gas G2 supplied from the scrubbing tower 4 is supplied to the chimney 5 via line L21, blower B2, and line L30, and discharged to the outside from the chimney 5. Furthermore, in this case, the control device 10 also controls the closing of valves V1 and V3. In addition, in this case, the control device 10 increases the amount of heating gas G3 supplied to the turbine 6b by controlling the gradual closing of valve V7.

The control device 10 may, for example, perform the opening control of valve V2, the closing control of valve V3, and the closing control of valve V1 in this order. Alternatively, the control device 10 may, for example, perform the stepwise closing control of valve V7 in parallel with the opening control of valve V2, the closing control of valve V3, and the closing control of valve V1.

Thus, in this embodiment, the supply unit 20 can supply at least a portion of the exhaust gas G2 blown from the blower B2 to the compressor 6a. The control device 10 in this embodiment controls the supply unit 20 according to the amount of waste heat from the incinerator 1, for example, causing the exhaust gas G2 supplied from the blower B2 to be supplied to the compressor 6a.

This allows the control device 10 in this embodiment to, for example, switch the incinerator 1's internal pressure control from offline operation control to assisted operation control.

Next, we will describe the incineration system 100 at the timing when the incinerator 1's internal pressure control is transitioned from assisted operation control to autonomous operation control (hereinafter also referred to as the second transition timing). Figure 13 is a diagram illustrating the incineration system 100 at the second transition timing. Note that the second transition timing may be, for example, the timing when the pressure on the inlet side of the compressor 6a in line L22 reaches the predetermined pressure.

The control device 10, for example, if it determines from the measured values of various instruments installed in each line that the pressure on the inlet side of the compressor 6a in line L22 has reached the predetermined pressure (the second transition timing has been reached), then, as shown in Figure 13, it controls the opening of valve V4, for example, to supply the exhaust gas G2 supplied from the scrubbing tower 4 to the turbocharger 6, bypassing the blower B2. Then, the control device 10 controls the stopping of blower B2, for example. In other words, in this case, the control device 10 determines that the amount of exhaust gas G2 induced by the turbocharger 6 is sufficient, and begins induced exhaust gas G2 solely by the turbocharger 6.

Furthermore, the control device 10, for example, controls the opening and closing of the valve V6 provided in the bypass L28 as needed. That is, in this case, the control device 10 controls the internal pressure of the incinerator 1 using the valve V6, instead of the blower B2 which has been stopped.

Subsequently, the exhaust gas G2 supplied from the smoke treatment tower 4 is supplied to the chimney 5 via, for example, a portion of line L21, line L24, a portion of line L22, compressor 6a, and line L30, as shown in Figure 13, and is then discharged to the outside from the chimney 5.

Furthermore, the air (heated gas G3) supplied by the blower B1 is supplied to the chimney 5 via, for example, line L51, part of line L14, compressor 7a, line L11, heat exchanger 2, part of line L12 and line L26, turbine 6b and line L23, as shown in Figures 9 and 13, and is discharged to the outside from the chimney 5. In addition, a portion of the air (heated gas G3) flowing through line L26 flows through a portion of line L26, then passes through bypass L28 and merges with the air flowing through line L23.

Thus, the control device 10 in this embodiment controls, for example, the blower B2. Furthermore, the supply unit 20 in this embodiment can supply, for example, exhaust gas G2 from the incinerator 1 to the compressor 6a, bypassing the blower B2. The control device 10 in this embodiment, for example, controls the blower B2 to stop and the supply unit 20 according to the amount of waste heat from the incinerator 1, causing the exhaust gas G2 from the incinerator 1 to be supplied to the compressor 6a, bypassing the blower B2.

In other words, the control device 10 starts performing autonomous operation control by controlling the supply unit 20 in response to a further increase in the amount of waste heat from the exhaust gas G1 discharged from the incinerator 1.

As a result, the control device 10 in this embodiment can control the internal pressure of the incinerator 1 by, for example, only inducing exhaust gas G2 using the turbocharger 6.

On the other hand, during autonomous operation control, if the energy of the heating gas G3 supplied from the heat exchanger 2 via line L26 decreases, for example, the control device 10 gradually reduces the opening of the valve V6 provided in the bypass L28, thereby suppressing the amount of heating gas G3 passing through the bypass L28 and preventing a decrease in the amount of heating gas G3 (thermal energy of the heating gas G3) supplied to the turbine 6b. Furthermore, if the control device 10 determines, for example, that the flow rate of the heating gas G3 flowing through the bypass L28 (first flow rate) satisfies the above-mentioned first condition, it initiates switching to assist operation control. Also, if the control device 10 determines, for example, that the ratio of the first flow rate to the flow rate of the heating gas G3 flowing through line L26 (second flow rate) satisfies the above-mentioned second condition, it initiates switching to assist operation control.

In other words, in this case, the control device 10 performs control to reverse each step (each step explained in Figure 13) that was taken when switching from assisted operation control to autonomous operation control, and controls the valves so that their open/closed states are as explained in Figure 12.

Furthermore, if the control device 10 determines, for example, that the temperature of the heating gas G3 flowing through line L26 has dropped to the fifth temperature during the execution of assist operation control, it will stop the turbocharger 6 and switch to offline operation.

In other words, in this case, the control device 10 performs control to reverse each step performed when switching from offline operation control to assisted operation control (each step described in Figures 11 and 12), and controls the open/closed state of each valve to the state described in Figure 10.

Thus, in this embodiment, for example, in autonomous operation control, when the amount of waste heat from the incinerator 1 falls below a predetermined threshold, the control device 10 stops the autonomous operation control, starts the blower B2, and controls the supply unit 20 to supply exhaust gas G2 from the incinerator 1 to the blower B2, and supplies the exhaust gas G2 blown from the blower B2 to the compressor 6a. The predetermined threshold here can be any value predetermined in advance (a so-called reference value) corresponding to the amount of waste heat from the incinerator 1. For example, it could be a temperature predetermined based on the temperature of the heating gas G3 flowing through line L26, or a rotational speed predetermined based on the rotational speed of the rotating shaft 6c of the turbocharger 6.

In other words, the control device 10 in this embodiment performs operational control according to the amount of waste heat in the exhaust gas G1 discharged from the incinerator 1, for example, even when the amount of waste heat in the exhaust gas G1 decreases, by controlling the supply unit 20.

As a result, the control device 10 in this embodiment can continue to control the internal pressure of the incinerator 1 even when, for example, the amount of waste heat in the exhaust gas G1 discharged from the incinerator 1 decreases.

[Incineration system 200 in the second embodiment]
Next, the incineration system 200 in the second embodiment will be described. Figures 14 and 15 illustrate an example of the configuration of the incineration system 200 in the second embodiment. The differences from the incineration system 100 in the first embodiment will be described below.

As shown in Figure 14, the incineration system 200 includes, for example, a bypass L31 between line L26 and line L23.

Bypass L31, like bypass L28, is a pipe that, for example, supplies heated gas G3 supplied from the heat exchanger 2 directly to the chimney 5, bypassing the turbine 6b. Specifically, bypass L31 connects, for example, the section between the downstream side of the connection point with line L12 in line L26 and the upstream side of the inlet of turbine 6b, and the section between the downstream side of the outlet of turbine 6b in line L23 and the upstream side of the inlet of chimney 5. In the example shown in Figure 14, bypass L31 connects to lines L26 and L23 at a point further from the turbine 6b than bypass L28, but bypass L31 may also connect to lines L26 and L23 at a point closer to the turbine 6b than bypass L28. The valve V6 provided in bypass L28 and the valve V31 provided in bypass L31 are, for example, valves with different capacities. Hereafter, the explanation will be based on the assumption that the capacity of valve V31 is smaller than the capacity of valve V6. Furthermore, the supply unit 20 is assumed to include the bypass L31 and the valve V31.

Furthermore, while Figure 14 shows valves V6 and V31 installed in parallel, they may also be installed in series. For example, a larger capacity valve could be installed upstream, and a smaller capacity valve downstream. Here, if we let P1 be the upstream pressure of the larger valve, P2 be the pressure between the two valves, and P3 be the downstream pressure of the smaller valve, then as the opening of the larger valve increases, P2 rises. Therefore, the pressure difference between P2 and P3 widens, increasing the flow rate even if the opening of the smaller valve remains the same.

The control device 10 adjusts the supply amount of the heated gas G3 supplied to the turbine 6b by, for example, controlling the opening and closing of valves V6 and V31.

This allows the incineration system 200 to stabilize the supply of heating gas G3 to the turbine 6b, even when there are large fluctuations in the amount of waste heat in the exhaust gas G1 discharged from the incinerator 1. Specifically, the control device 10 finely adjusts the amount of air supplied to the turbine 6b by, for example, adjusting the opening degree of valve V31 (the valve with the smaller capacity). Specific examples of the opening and closing control of valves V6 and V31 will be described below.

[Specific examples of opening and closing control of valves V6 and V31]
Figure 15 illustrates specific examples of opening and closing control of valves V6 and V31. Specifically, Figure 15(A) is a graph illustrating a specific example of opening and closing control of valve V31 (the valve with the smaller capacity), and Figure 15(B) is a graph illustrating a specific example of opening and closing control of valve V6 (the valve with the larger capacity). In each graph shown in Figure 15, the horizontal and vertical axes represent time and valve opening degree, respectively. The following explanation will focus on the case where the optimal opening degree range for valve V31 (hereinafter also referred to as the predetermined range) is between A1 and B1. The optimal opening degree of the valve refers to the valve opening degree range in which flow rate adjustment can be performed with the accuracy (so-called high precision) desired by the designer of the incineration system 200. Specifically, in the example in Figure 15, when the opening degree of valve V31 is between A1 and B1, high-precision flow rate adjustment becomes possible with valve V31.

The control device 10, for example, controls the opening and closing of valves V6 and V31 so that the opening degree of valve V31 falls between A1 and B1.

Furthermore, if the opening degree of valve V31 falls outside the range between A1 and B1, the control device 10 adjusts, for example, the opening degree of valve V6. The control device 10 also adjusts the opening degree of valve V6, for example, so that the opening degree of valve V31 remains constant.

Specifically, for example, as shown at time T1 in Figure 15(A), if the opening degree of valve V31 becomes greater than A1 (the upper limit of the optimal opening degree of valve V31), the control device 10 adjusts the valve opening degree of valve V6 by gradually increasing it by a predetermined amount while simultaneously decreasing the opening degree of valve V31, as shown in the time period between time T1 and time T2 in Figures 15(A) and 15(B). As a result, for example, as shown at time T2 in Figure 15(A), when the opening degree of valve V31 decreases to A2, the control device 10 terminates the adjustment to increase the opening degree of valve V6, as shown at time T2 in Figure 15(B).

Furthermore, for example, as shown at time T3 in Figure 15(A), if the opening degree of valve V31 becomes smaller than B1 (the lower limit of the optimal opening degree of valve V31), the control device 10 adjusts the valve opening degree of valve V6 by gradually decreasing it by a predetermined amount while increasing the opening degree of valve V31, as shown in the time period between time T3 and time T4 in Figures 15(A) and 15(B). As a result, for example, as shown at time T4 in Figure 15(A), if the opening degree of valve V9 increases to B2, the control device 10 terminates the adjustment to decrease the opening degree of valve V6, as shown at time T4 in Figure 15(B).

In other words, if the capacity of valve V31 is smaller than that of valve V6, valve V31 allows for finer adjustment of the supply amount of heating gas G3 than valve V6. Therefore, the control device 10 adjusts the amount of heating gas G3 flowing through bypass L28 and bypass L31 by adjusting (fine-tuning) the opening degree of valve V31. For example, if the amount of heating gas G3 supplied from the heat exchanger 2 via line L26 increases, making it impossible to adjust valve V31 within the optimal range, the control device 10 increases the opening degree of valve V6, thereby enabling the adjustment of valve V31 within the optimal range again. Similarly, if the amount of heating gas G3 supplied from the heat exchanger 2 via line L26 decreases, making it impossible to adjust valve V31 within the optimal range, the control device 10 decreases the opening degree of valve V6, thereby enabling the adjustment of valve V31 within the optimal range again.

This allows the control device 10 to control the supply amount of heating gas G3 supplied to the turbine 6b, for example, by fine-tuning the valve V31, which allows for precise adjustments.

In this case, the control device 10 may, for example, continuously adjust the opening degree of valve V6 so that the opening degree of valve V31 remains constant.

Furthermore, while the above example described a case where two bypasses (bypass L28 and bypass L31) are provided between line L26 and line L23, it is also possible to provide three or more bypasses between line L26 and line L23, each having a valve with a different capacity. That is, the control device 10 may, for example, adjust the opening degree of valve V31, which is one of three or more valves with different capacities, and the opening degree of valve V6, which is one of three or more valves with different capacities and has a larger capacity than valve V31, thereby adjusting the opening degree of valve V6 according to the opening degree of valve V31.

[Incineration system 300 in the third embodiment]
Next, the incineration system 300 in the third embodiment will be described. Figures 16 and 17 are diagrams illustrating an example configuration of the incineration system 300 in the third embodiment. The differences from the incineration system 100 in the first embodiment and the incineration system 200 in the second embodiment will be described below.

In the first embodiment (incineration system 100) and the second embodiment (incineration system 200), the case where the system switches to offline operation control and stops the turbocharger 6 due to a decrease in waste heat output preventing the turbocharger 6 from performing assist operation control was described. In contrast, the third embodiment describes a case where, for example, even when the waste heat output has not decreased, the turbocharger 6 is forcibly stopped while sludge incineration in the incinerator 1 continues. Two such cases for stopping the turbocharger 6 are envisioned, for example:

The first scenario is when it is necessary to induce more exhaust gas G2 than the amount that the turbocharger 6 can induce. There is a performance limit on the amount of exhaust gas G2 that the turbocharger 6 can induce. Therefore, for example, if exhaust gas G2 exceeding the turbocharger 6's limit is supplied to the turbocharger 6, a malfunction of the turbocharger 6 may occur.

The second case is when the turbocharger 6 is stopped for the purpose of periodic inspection of the turbocharger 6, or when the turbocharger 6 is stopped due to a malfunction in the turbocharger 6.

In this case, the control device 10 responds, for example, to a signal instructing the turbocharger 6 to stop (hereinafter also referred to as a stop signal) and controls the supply of heated gas G3 in the supply unit 20 to stop the supply of heated gas G3, heated by the heat exchanger 2, to the turbine 6b. To stop the turbocharger 6 in this way, the control device 10 reduces the amount of heated gas G3 supplied to the turbine 6b and transitions from autonomous operation control to assisted operation control.

Furthermore, even when the turbocharger 6 is stopped, the control device 10 continues to control the internal pressure of the incinerator 1 and continue sludge combustion. In response to this stop signal, the control device 10 controls the supply of exhaust gas G2 in the supply unit 20, supplying the heated gas G3 from the heat exchanger 2 to the chimney 5, bypassing the turbocharger 6.

Next, we will explain the stopping of the supercharger 6, referring to the flowchart in Figure 16. Figure 17 is a diagram illustrating the stopping of the supercharger 6.

The control device 10 executes the processing from step S11 onwards in Figure 16 in response to a stop signal instructing the turbocharger 6 to stop. The stop signal may be, for example, a stop instruction signal transmitted from the control panel when an operator presses the stop instruction button (not shown) on the control panel of the incineration system 300. Alternatively, the stop signal may be, for example, an alarm signal detected by the turbocharger 6's fault detection system (not shown). Furthermore, the stop signal may be a signal generated by the control device 10 itself when, for example, it is necessary to induce more exhaust gas G2 than the turbocharger 6 can induce.

Specifically, the control device 10, for example, in response to a stop signal instructing the turbocharger 6 to stop, determines the current operation control being performed in the incineration system 300 (step S11 in Figure 16). The control device 10's memory (not shown) may store information indicating, for example, that one of the following is currently being performed as the operation control: autonomous operation control, assisted operation control, or offline operation control (hereinafter also referred to as execution control information). The control device 10 may then perform step S11 by, for example, referring to the execution control information.

Then, if the control device 10 determines that the current operation control is autonomous operation control (autonomous operation control in step S11 of Figure 16), it switches to, for example, assisted operation control (step S12 of Figure 16). Specifically, when the control device 10 switches to assisted operation control, it reduces the amount of heating gas G3 supplied to the turbine 6b by, for example, increasing the opening degree of valve V7 provided in line L27, thereby switching to assisted operation control.

In this switching control, the control device 10 determines, for example, from the measured values of various instruments installed in each line, that the energy of the heated gas G3 supplied to the turbine 6b is not insufficient to operate the supercharger 6, and then starts supplying exhaust gas G2 to the compressor 6a using the blower B2. The measured values referenced in the aforementioned determination are, for example, the flow rate of the heated gas G3 measured by the flow meter installed in the bypass L28, and the temperature of the heated gas G3 measured by the thermometer installed in line L26.

Then, for example, after step S12, the control device 10 switches to offline operation control (step S13 in Figure 16). When switching to offline operation control, for example, the control device 10 controls the opening of valve V1 located in line L29 and the closing of valve V2 located in line L22, thereby stopping the supply of exhaust gas G2 from the blower B2 to the compressor 6a and starting the supply of exhaust gas G2 from the blower B2 to the chimney 5.

On the other hand, if the control device 10 determines that the current driving control is assisted driving control (assisted driving control in step S11 of Figure 16), it switches to, for example, offline driving control (step S13 of Figure 16).

Furthermore, the control device 10 may, for example, detect the rotational speed of the turbocharger 6's rotating shaft 6c after transitioning to offline operation control, and if it determines that the rotational speed has reached a predetermined number of rotational speeds (e.g., 0), it may notify the operator that the turbocharger 6 has stopped.

Thus, in this embodiment, the control device 10, for example, responds to a signal instructing the turbocharger 6 to stop, controls the supply unit 20 to stop the supply of the heated gas G3, heated by the heat exchanger 2, to the turbine 6b, and supplies the exhaust gas G2 blown from the blower B2 to the chimney 5, bypassing the compressor 6a.

This allows the control device 10 in this embodiment to, for example, spontaneously stop the turbocharger 6. In other words, the control device 10 in this embodiment can stop the turbocharger 6 while continuing sludge incineration in the incinerator 1, even when the waste heat output has not decreased.

1: Incinerator 1a: Fluidized bed 2: Heat exchanger 3: Dust collector 4: Scrubbing tower 5: Chimney 6: Supercharger 6a: Compressor 6b: Turbine 6c: Rotating shaft 7: Supercharger 7a: Compressor 7b: Turbine 7c: Rotating shaft 10: Control device 20: Supply unit 100: Incineration system B1: Blower B2: Blower L1: Line L2: Line L3: Line L11: Line L12: Line L13: Line L14: Line L15: Line L21: Line L22: Line L23: Line L24: Line L25: Line L26: Line L27: Line L28: Bypass L29: Line L30: Line L31: Bypass L41: Line L51: Line L52: Line L53: Line L54: Line V1: Valve V2: Valve V3: Valve V4: Valve V5: Valve V6: Valve V7: Valve V8: Valve V9: Valve V10: Valve V21: Valve V22: Valve V23: Valve V24: Valve V31: Valve

Claims (8)

An incinerator for burning the materials to be processed,
A first supercharger having a first compressor for drawing in exhaust gas discharged from the incinerator and a first turbine for driving the first compressor,
A blower that draws in the exhaust gas and blows it out,
A supply unit that supplies the exhaust gas blown from the blower to at least one of the first compressor and the chimney, supplies the air supplied to the incinerator to a heat exchanger that raises the temperature using the waste heat of the incinerator, and supplies a portion of the heated gas raised by the heat exchanger to at least one of the first turbine and the chimney,
The system includes a control device for controlling the supply unit ,
The control device controls the supply unit according to the amount of waste heat from the incinerator, and supplies the exhaust gas blown from the blower to the chimney , in an incineration system. The system includes a second supercharger having a second compressor that compresses the aforementioned air to generate compressed gas, and a second turbine that drives the second compressor.
The supply unit is capable of supplying the compressed gas to the heat exchanger, supplying the heated gas heated by the heat exchanger to the second turbine, and further supplying the heated gas discharged from the second turbine to the incinerator.
The incineration system according to claim 1, wherein the control device controls the supply unit according to the amount of waste heat from the incinerator, and causes a portion of the heated gas supplied from the heat exchanger to be supplied to at least one of the first turbine and the chimney. The incineration system according to claim 2 , wherein the control device controls the supply unit according to the amount of waste heat from the incinerator and increases the amount of heated gas supplied from the heat exchanger to the first turbine. The supply unit is capable of supplying at least a portion of the exhaust gas blown from the blower to the first compressor.
The incineration system according to claim 3 , wherein the control device controls the supply unit according to the amount of waste heat from the incinerator and causes the exhaust gas supplied from the blower to be supplied to the first compressor. The control device controls the blower,
The supply unit is capable of supplying the exhaust gas from the incinerator to the first compressor, bypassing the blower.
The incineration system according to claim 4, wherein the control device controls the blower to stop and the supply unit in accordance with the amount of waste heat from the incinerator, and switches to a supercharger autonomous operation control that supplies the exhaust gas discharged from the incinerator to the first compressor, bypassing the blower. The incineration system according to claim 5, wherein, in the supercharger autonomous operation control, when the amount of waste heat from the incinerator falls below a predetermined threshold, the control device stops the supercharger autonomous operation control, starts the blower and controls the supply unit to supply the exhaust gas from the incinerator to the blower, and supplies the exhaust gas blown from the blower to the first compressor. The control device, in response to a signal instructing the first supercharger to stop, controls the supply unit to stop the supply of the heated gas, which has been heated by the heat exchanger, to the first turbine.
The incineration system according to claim 1 , wherein the exhaust gas blown from the blower is supplied to the chimney, bypassing the first compressor. An incinerator for burning the materials to be processed,
A first supercharger having a first compressor for drawing in exhaust gas discharged from the incinerator and a first turbine for driving the first compressor,
A blower that draws in the exhaust gas and blows it out,
An incineration system comprising: a supply unit that supplies the exhaust gas blown from the blower to at least one of the first compressor and the chimney; supplies the air supplied to the incinerator to a heat exchanger that raises the temperature of the air supplied to the incinerator using the waste heat of the incinerator; and a supply unit that can supply a portion of the heated gas raised by the heat exchanger to the first turbine and the chimney, respectively.