JP6947608B2 - How to operate waste treatment equipment and waste treatment equipment - Google Patents

Description

The present invention relates to a waste treatment facility equipped with a heat treatment furnace for incinerating waste such as sludge, and a method for operating the waste treatment facility.

Various sewage is purified by biological treatment using microorganisms and then discharged into rivers or reused. A large amount of sludge generated by such biological treatment is dehydrated and then buried in a final disposal site, or incinerated in a heat treatment furnace including a fluidized bed furnace and a shaft furnace.

In such a heat treatment furnace, it is necessary to supply a sufficient amount of combustion air to the inside of the furnace by using a push-in blower, and to attract exhaust gas by using an induction blower to maintain the inside of the furnace at a negative pressure. The power cost, that is, the electric power cost, required for the blower and the attracting blower is very high.

Patent Document 1 proposes a waste treatment facility capable of operating a furnace while suppressing the power cost required for a push-in blower. The waste treatment facility is a waste treatment facility equipped with a heat treatment furnace including a fluidized bed furnace and a shaft furnace for incinerating waste such as sludge, and the combustion heat and / or flue in the heat treatment furnace. A heat exchanger that preheats the combustion air by the retained heat of the exhaust gas guided to, a turbine that rotates by the combustion air preheated by the heat exchanger, and a compressor that supplies the combustion air to the heat exchanger by the rotation of the turbine. It is equipped with a supercharger including the above and a push-in blower that precompresses and supplies combustion air to the compressor.

In such a waste treatment facility, the compression work by the indentation blower is increased to the compression work by the compressor, so even if the loss such as the ventilation pressure loss generated when supplying the combustion air to the heat treatment furnace is subtracted, it is sufficient. The combustion air can be supplied, and the power of the push-in blower required for that purpose can be sufficiently suppressed by providing the supercharger and the first heat exchanger, and the power cost can be reduced as a whole.

Japanese Unexamined Patent Publication No. 2016-180528

In the above-mentioned waste treatment equipment, the air pressure to be supplied by the push-in blower decreases as the amount of waste heat recovered by the heat exchanger increases, and as a result, the power required for the push-in blower is suppressed. If the push blower is stopped in a situation where the blower by the push blower is practically unnecessary, the push blower is restarted or restarted with a slight fluctuation after that, and the state is repeated at intervals of several minutes and becomes stable. There wasn't.

In addition, large indentation blowers of tens to hundreds of kilowatts need to reduce excessive starting current, so the Star Delta starting method and Condorfa starting method are adopted, and it is not possible to start so quickly. Therefore, there is a possibility that the degree of fluctuation of the required air flow amount will be further increased due to the response delay. Therefore, the push-in blower could not be stopped easily.

An object of the present invention is to provide a waste treatment facility and a method for operating the waste treatment facility, which can avoid frequent start and stop of a large indentation blower even if the required air amount fluctuates.

In order to achieve the above object, the first characteristic configuration of the waste treatment facility according to the present invention is a heat treatment furnace for incinerating waste such as sludge, as described in claim 1 of the document in the scope of the patent claim. It is rotated by the first heat exchanger that preheats the combustion air by the combustion heat in the heat treatment furnace and / or the retained heat of the exhaust gas guided to the flue, and the combustion air preheated by the first heat exchanger. A waste treatment facility including a supercharger including a turbine and a compressor that supplies combustion air to the first heat exchanger by rotation of the turbine, and a push blower that supplies combustion air to the compressor. The point is that it is provided with an auxiliary push blower that supplies air to the air supply path from the push blower to the compressor with a lower power than the push blower.

When it is necessary to start the push-in blower quickly or repeatedly start and stop it frequently, by driving an auxiliary push-in blower with a lower power than the push blower, the required amount of air can be blown quickly. In addition, even if the auxiliary indentation blower is repeatedly started or stopped, it is possible to avoid the generation of an excessive starting current.

In the second characteristic configuration, as described in claim 2, in addition to the first characteristic configuration described above, the required air volume to be supplied to the compressor by the indentation blower is set to a preset lower limit air flow amount. In that case, it is provided with a control unit for stopping the compressor.

When the required amount of air blown by the push-in blower reaches a preset lower limit blower amount, the control unit promptly stops the push-in blower, and wasteful power consumption and pressure loss caused by the blower are avoided.

As described in claim 3, in addition to the above-mentioned second feature configuration, the control unit has the required air flow amount as the lower limit air flow amount while the push-in blower is stopped. The point is that the auxiliary push-in blower is activated when the value exceeds.

When the required amount of air blows exceeds the lower limit amount of air while the indentation blower is stopped, the control unit operates the auxiliary indentation blower instead of the indentation blower, and as a result, the amount of combustion air supplied to the heat treatment furnace is responsively targeted. The heat treatment furnace can be controlled to a stable combustion state.

As described in claim 4, the fourth feature configuration is, in addition to the third feature configuration described above, until the required air flow reaches a start air volume larger than the lower limit air flow. During the period, the auxiliary push-in blower is operated, and when the required blower amount exceeds the start-up blower amount, the push-in blower is operated in place of the auxiliary push-blower.

The control unit stops the push-in blower when the required blower amount required for the push-in blower reaches the lower limit blower amount, and even if the required blower amount exceeds the lower limit blower amount in the stopped state, the push-in blower is not immediately operated and the lower limit blower is blown. By providing a hysteresis characteristic that activates the push-in blower when the start-up blower volume exceeds the air volume, frequent start and stop of the push-in blower is avoided, and the start-up characteristic is used instead of the push-in blower until the start-up blower volume is reached. By operating an excellent auxiliary push-in blower, it responds quickly to fluctuations in the amount of air blown.

As described in claim 5, the fifth characteristic configuration is, in addition to any of the first to fourth characteristic configurations described above, an input that adjusts the amount of heat input of the combustion air supplied to the turbine. The points 1 to 4 are provided with a calorific value adjusting mechanism.

When the amount of waste heat recovered by the first heat exchanger becomes excessive and the amount of air supplied to the compressor, that is, the amount of suction air from the compressor exceeds the required amount, the heat input to the turbine is adjusted by the heat input adjustment mechanism. NS. As a result, the amount of air supplied to the compressor can be adjusted to the target amount of air.

As described in claim 6, the sixth feature configuration is, in addition to the fifth feature configuration described above, the heat input amount adjusting mechanism is a flow rate adjusting mechanism provided in the air supply path to the compressor. It is in the point that it is composed.

Air supply path to the compressor when the amount of waste heat recovered by the first heat exchanger becomes excessive with the push-in blower stopped and the amount of air supplied to the compressor, that is, the amount of suction air supplied by the compressor exceeds the required amount. The heat input to the turbine is adjusted by operating the flow rate adjusting mechanism provided in the above to reduce the amount of suction air.

As described in claim 7, the seventh feature configuration is that, in addition to the sixth feature configuration described above, the flow rate adjusting mechanism is provided in a bypass path that bypasses the push-in blower. ..

If the air supply path to the compressor includes the air passage of the push blower, the fan becomes a resistance and pressure loss occurs when the push blower is stopped. If a bypass path is provided, such pressure is generated. No loss occurs. When the amount of suction air by the compressor exceeds the required amount, the amount of suction air can be quickly adjusted by the flow rate adjusting mechanism provided in the bypass path.

As described in claim 8, the eighth characteristic configuration is, in addition to the above-mentioned first to seventh characteristic configuration, the temperature of the preheated air sent from the turbine is used as the heat possessed by the exhaust gas. The point is that it is equipped with a second heat exchanger that is adjusted by.

When the heat input amount adjusting mechanism is activated, the temperature of the preheated air sent from the turbine and guided to the heat treatment furnace as combustion air fluctuates, which may hinder the stable operation of the heat treatment furnace. Even in such a case, by providing the second heat exchanger, the temperature of the preheated air sent from the turbine and guided to the heat treatment furnace can be adjusted to an appropriate temperature.

As described in claim 9, the first characteristic configuration of the operation method of the waste treatment facility according to the present invention is the heat treatment furnace for incinerating waste such as sludge, and the heat of combustion in the heat treatment furnace and /. Alternatively, the first heat exchanger that preheats the combustion air by the retained heat of the exhaust gas guided to the flue, the turbine that rotates by the combustion air preheated by the first heat exchanger, and the first by the rotation of the turbine. A supercharger including a compressor that supplies combustion air to a heat exchanger, a push blower that supplies combustion air to the compressor, and a push blower that is connected in parallel with the push blower and supplies air to the compressor. It is a method of operating a waste treatment facility equipped with an auxiliary indentation blower having a lower power than that of the indentation blower in a state where the supply amount of combustion air to the heat treatment furnace is maintained at a predetermined amount. When the required air blower to be supplied to the compressor reaches the preset lower limit air flow amount, the push blower is stopped, and when the required air blower exceeds the lower limit air blower while the push blower is stopped, the auxiliary push blower is used. Is at the point of operating.

As described in claim 10, the second feature configuration is, in addition to the first feature configuration described above, the auxiliary air volume until the required air flow amount reaches a start air flow amount larger than the lower limit air flow amount. The point is to operate the push-in blower, and when the required blower amount exceeds the start-up blower amount, the push-in blower is operated in place of the auxiliary push-blower.

As described in claim 11, the third feature configuration is, in addition to the first or second feature configuration described above, a heat input adjusting mechanism for adjusting the heat input amount of the combustion air supplied to the turbine. Is further provided in the waste treatment facility, and the amount of heat input of the combustion air supplied to the turbine via the heat input amount adjusting mechanism is adjusted so that the amount of combustion air supplied to the compressor becomes the target amount of air. There is a point to adjust.

As described above, according to the present invention, it is possible to provide a waste treatment facility and an operation method of the waste treatment facility that can avoid frequent start and stop of a large push-in blower even if the required air amount fluctuates. It became so.

Explanatory drawing of waste treatment equipment and operation method of waste treatment equipment by this invention (A), (b), and (c) are diagrams explaining the Brayton cycle of the turbocharger, and (d) is a characteristic diagram showing the correlation between the blower power and the amount of waste heat recovered. An explanatory diagram of a waste treatment facility and an operation method of the waste treatment facility according to the present invention, showing another embodiment. An explanatory diagram of a waste treatment facility and an operation method of the waste treatment facility according to the present invention, showing another embodiment. An explanatory diagram of a waste treatment facility and an operation method of the waste treatment facility according to the present invention, showing another embodiment. An explanatory diagram of a waste treatment facility and an operation method of the waste treatment facility according to the present invention, showing another embodiment. An explanatory diagram of a waste treatment facility and an operation method of the waste treatment facility according to the present invention, showing another embodiment.

Hereinafter, embodiments of the waste treatment equipment and the operation method of the waste treatment equipment according to the present invention will be described.

FIG. 1 shows a waste treatment facility 100 that incinerates waste such as sludge. The waste treatment facility 100 includes a sludge storage tank 1 in which sludge to be incinerated is stored, a sludge input mechanism 11, a fluidized bed incinerator 2 which is an example of a heat treatment furnace, an exhaust gas treatment facility, and the like. There is.

In the fluidized bed incinerator 2, the sludge supplied from the sludge charging mechanism 11 is charged into the fluidized bed formed by the high temperature air supplied from the air supply mechanism 3 and heated, and the gasified sludge is discharged to the free board section. It is a heat treatment furnace that burns at 20. Below the freeboard section 20, a heating burner 21 that heats the inside of the furnace at the time of startup is arranged, and an auxiliary burner 22 that supplements the amount of heat required for burning sludge after the temperature of the furnace has risen is provided.

Along the flue 10 of the fluidized bed incinerator 2, the first heat exchanger 5 that preheats the combustion air by the retained heat of the exhaust gas, the dust collector 6 that collects soot and dust, and the exhaust gas by spraying an alkaline agent. A flue gas treatment tower 7 or the like that neutralizes the acidic gas component inside is arranged.

An attracting blower 8 is provided on the downstream side of the smoke exhaust treatment tower 7 to attract the exhaust gas of the flue 10 and maintain the inside of the furnace at a negative pressure, and the exhaust gas attracted by the attracting blower 8 is purified by each exhaust gas treatment facility. After that, it is exhausted from the chimney 9.

The air supply mechanism 3 described above includes turbofan type push blowers 30, 30a, a supercharger 40, and a first heat exchanger 5. The turbocharger 40 includes a compressor 40c and a turbine 40t that are integrally rotatably connected by a drive shaft 40a.

Combustion air precompressed to about 5 kPa by the indentation blower 30 is supplied to the air supply port of the compressor 40c constituting the supercharger 40, compressed to about 100 to 300 kPa, and then supplied to the first heat exchanger 5. NS.

The combustion air that has been heat-exchanged with the exhaust gas of 800 to 1000 ° C. in the first heat exchanger 5 and preheated to 500 to 750 ° C. is supplied to the turbine 40t in the subsequent stage, the turbine 40t is rotationally driven, and the drive shaft 40a The connected compressor 40c is rotationally driven.

Compressed air at 400 to 650 ° C. and about 30 to 40 kPa discharged from the turbine 40t is supplied to the fluidized bed incinerator 2 as fluidized and combustion air to form a fluidized bed. The pressure described in this specification is a gauge pressure.

Since the combustion air precompressed by the push blower 30 is supplied to the compressor 40c of the supercharger 40, the air compressed not only by the compressor 40c but also by the push blower 30 is preheated by the heat exchanger 5. become. As a result, the expansion work of the turbine 40t becomes equal to or greater than the compression work of the compressor 40c, and the drive of the supercharger 40 is maintained. It is configured to be able to supply combustion air at a high pressure.

As shown in FIG. 2A, the gas turbine and the supercharger are devices that operate according to the Brayton cycle, and the compression process in the compressor (1 → 2 in the figure) and the supply in the combustor or heat exchanger. It consists of a thermal process (2 → 3 in the figure) and an expansion process in the turbine (3 → 4 in the figure). Rotation is maintained when the expansion work in the turbine exceeds the compression work in the compressor.

However, as shown in FIG. 2B, if a configuration is adopted in which the air supply port of the compressor 40c is opened to the atmosphere and the outside air is directly sucked, the expansion work amount x in the turbine 40t is the air pressure loss to the fluidized bed. When constrained by x1 and the ventilation resistance x2, the expansion work amount x in the turbine 40t becomes less than the compression work amount y in the compressor 40c (x <y), and the drive of the turbocharger 40 cannot be maintained.

Therefore, it is configured to supply air from the push-in blower 30 to the compressor 40c via the air passage.

As shown in FIG. 2C, the combustion air precompressed by the indentation blower 30 is supplied to the air supply port of the compressor 40c, so that the amount of compression work y in the compressor 40c is substantially equal to the precompression amount y1. (X> y), and even if there is a ventilation pressure loss x1 and a ventilation resistance x2 to the fluidized bed, the drive of the supercharger 40 can be maintained.

Further, since the discharge pressure by the push-in blower 30 can be reduced as compared with the case where the supercharger 40 is not used, the power consumption of the push-in blower 30 can be reduced. However, at the initial stage of starting up the fluidized bed incinerator 2, it is necessary to increase the blowing pressure in order to form the fluidized bed exclusively with the indentation blower 30, but the ventilation resistance of the turbocharger 40 is small, and by starting up. As the temperature rises, the effect of reducing the power cost of the supercharger 40 can be obtained.

The waste treatment facility 100 is provided with a control unit 70. The control unit 70 is suitable for the fluidized bed incinerator 2 by controlling the rotation speed of the push blower 30 based on the oxygen concentration of the exhaust gas detected by the oxygen gas sensor Sg provided at the outlet of the free board unit 20. It is configured to regulate the supply of combustion air so that it is maintained in a combustion state.

The control unit 70 calculates the target air amount to be supplied to the furnace by performing a predetermined control calculation based on the deviation between the oxygen concentration of the exhaust gas detected by the oxygen gas sensor Sg and the target oxygen concentration.

The amount of air required for complete combustion is set based on the theoretical amount of air assumed in advance, and the reference oxygen concentration remaining in the exhaust gas at that time is calculated. A feedback calculation is performed so that the target air amount is reduced when the oxygen concentration of the exhaust gas detected by the oxygen gas sensor Sg is higher than the reference oxygen concentration, and the target air amount is increased when the oxygen concentration of the exhaust gas is lower than the reference oxygen concentration. Is done.

The control unit 70 calculates the target rotation speed of the push blower 30 based on the deviation between the air amount detected by the flow meter Sq installed between the push blower 30 and the compressor 40c and the target air amount, and the push blower 30. The inverter 75 is controlled so that 30 becomes the target rotation speed.

By using the oxygen concentration in the exhaust gas as an index, the appropriate amount of combustion air for the organic components of the sludge burned in the fluidized bed incinerator 2 can be grasped, and the target amount is set based on the index. Therefore, it becomes possible to supply combustion air without a large excess or deficiency with respect to the required amount.

FIG. 2D shows the relationship between the amount of waste heat recovered by the first heat exchanger 5 and the power required for the push-in blower 30 on the premise that the amount of combustion air is kept constant. Since the rotation speed of the turbocharger 40 increases as the amount of waste heat recovered increases, the amount of air to be supplied to the compressor 40C by the push-in blower 30, that is, the required amount of blown air decreases, and the push-in blower 30 is required accordingly. It has been shown that power is reduced. When the amount of waste heat recovered by the first heat exchanger 5 increases, a sufficient amount of compressed air is obtained by the amount of compressed air drawn by the compressor 40c, and the amount of air blown by the push-in blower 30 becomes unnecessary, so that the push-in blower 30 is stopped.

If the amount of waste heat recovered by the first heat exchanger 5 decreases in such a state, the amount of heat input to the turbine 40t of the supercharger 40 decreases. Therefore, the control unit 70 reduces the amount of combustion required for the fluidized bed incinerator 2. It is necessary to restart the push-in blower 30 so that the amount of air is sufficient, but when starting a large push-in blower 30 of several tens of kilowatts or more, a starting circuit for suppressing the starting current is provided. , I can't launch it so suddenly. Therefore, there is a possibility that the control characteristics deteriorate due to the delay and the amount of air blown by the indentation blower 30 fluctuates, so that stable equipment operation cannot be performed.

Therefore, in response to the former problem, the waste treatment facility 100 is provided with an auxiliary push blower 30a that supplies air to the air supply path 34 from the push blower 30 to the compressor 40c with a lower power than the push blower 30. In response to the latter problem, a heat input adjusting mechanism 50 for adjusting the heat input to the turbine 40t is provided so that the air supply amount to the compressor 40c becomes the target air amount with the push-in blower 30 stopped. ing. The auxiliary push blower 30a, which has a lower power than the push blower 30, can secure the same amount of air as the push blower 30 when the required air flow is small, and the discharge pressure required at that time is low. Therefore, it is a blower that can be operated with low power.

As the auxiliary push-in blower 30a, a turbofan blower of about 10 kW can be preferably adopted. With such an auxiliary push-in blower 30a, good rise characteristics can be obtained while suppressing the starting current.

The control unit 70 is, for example, in a state where the supply amount of combustion air to the fluidized bed incinerator 2 is maintained at a predetermined amount, and when the required air flow amount by the push-in blower 30 reaches a preset lower limit blower amount, the push-in blower When the required air amount exceeds the lower limit air amount while the incinerator 30 is stopped and the incinerator 30 is stopped, the auxiliary incinerator 30a is controlled to operate instead of the incinerator 30. The specific value of the lower limit blower amount is not particularly limited, but for example, a value that becomes the blower power in the vicinity of the intersection of the characteristic line of FIG. 2D and the x-axis may be appropriately set.

Then, the control unit 70 operates the auxiliary push-in blower 30a until the required blower reaches a starter blower amount larger than the lower limit blower amount, and when the required blower amount exceeds the start-up blower amount, the control unit 70 replaces the auxiliary push-in blower 30a. It is configured to operate the push-in blower 30.

It has a hysteresis characteristic that activates the push-in blower 30 when the start-up blower amount exceeds the lower limit blower without immediately operating the push-in blower 30 even if the required blower amount exceeds the lower limit blower amount with the push-in blower 30 stopped. By doing so, the frequent start and stop of the push blower 30 is avoided, and the auxiliary push blower 30a having excellent starting characteristics is operated instead of the push blower 30 until the start air volume is reached. With such a configuration, it is possible to quickly respond to fluctuations in the amount of air blown and adjust the amount of combustion air supplied to the fluidized bed incinerator 2 to a target amount with good responsiveness. Can be controlled to a stable combustion state.

Specifically, when the push-in blower 30 is operated, the dampers 32 and 33 as flow rate adjusting mechanisms provided in the bypass path 35 guided to the air supply path 34 to the compressor 40c and the auxiliary air supply path 36 provided with the auxiliary push-blower 30a. When the push blower 30 is stopped, the damper 31 as a flow rate adjusting mechanism provided at the outlet of the push blower 30 is closed, and the damper 32 provided in the bypass path 35 for supplying air by the compressor 40c is opened. As will be described later, these flow rate adjusting mechanisms function as the heat input adjusting mechanism 50 for adjusting the heat input to the turbine 40t.

When transient air blowing is required in this state, the damper 33 provided in the auxiliary air supply path 36 is opened and the auxiliary indentation blower 30a is operated. The upstream side of the air supply path 34, the bypass path 35, and the auxiliary air supply path 36 is connected to an odor gas collecting unit provided in a water treatment facility or a sludge storage facility, which is a source of sludge, and is a fluidized bed incinerator. It is configured to be burned and deodorized in 2.

The above-mentioned heat input amount adjusting mechanism 50 will be described. When the amount of waste heat recovered by the first heat exchanger 5 becomes excessive and the amount of air supplied to the compressor 40c, that is, the amount of suction air taken by the compressor 40c exceeds the required amount, the heat input adjusting mechanism 50 sends the turbine 40t to the turbine 40t. The amount of heat input is adjusted. As a result, the rotation speed of the compressor 40c is reduced, and the air supply amount can be adjusted to the target air amount.

As shown in FIG. 1, the heat input adjusting mechanism 50 has a bypass path 51 and a bypass path 51 that directly guide a part of the air sent from the compressor 40c and guided to the first heat exchanger 5 to the introduction port side of the turbine 40t. It is composed of a damper mechanism as a flow rate adjusting mechanism 52 provided in the above.

A part of the air sent from the compressor 40c and guided to the first heat exchanger 5 is guided to the introduction port side of the turbine 40t via the bypass path 51. The amount of heat input to the turbine 40t is adjusted by merging the air preheated by the first heat exchanger 5 and the air guided to the bypass path 51 via the flow rate adjusting mechanism 52 and introducing the air into the turbine 40t. ..

More specifically, in the control unit 70, when the amount of heat exchanged in the first heat exchanger 5 increases and the amount of air detected by the flow meter Sq rises above the target amount, the air bypassed in the bypass path 51 By adjusting the flow rate adjusting mechanism 52 so as to increase the amount, the amount of heat input to the turbine 40t is reduced, and conversely, the amount of heat exchanged by the first heat exchanger 5 is reduced and detected by the flowmeter Sq. When the amount of air collected is lower than the target amount, the flow rate adjusting mechanism 52 is adjusted so as to increase the amount of air bypassed in the bypass path 51, so that the amount of heat input to the turbine 40t is controlled to increase. It is configured. Needless to say, the heat input adjusting mechanism 50 may be operated regardless of the state of the push-in blower 30.

It is also possible to exert the function as the flow rate adjusting mechanism 52 by the damper 32 provided in the bypass path 35 that bypasses the push-in blower 30. For example, when the amount of heat exchanged in the first heat exchanger 5 increases and the amount of air detected by the flow meter Sq rises above the target amount, the opening degree of the damper 32 is narrowed down and the air supply path from the bypass path 35 By limiting the amount of air supplied to 34, the amount of combustion air supplied to the fluidized bed incinerator 2 can be stabilized. That is, the bypass passage 35 and the damper 32 serve as a heat input amount adjusting mechanism 50 that adjusts the heat input amount to the turbine 40t so that the air supply amount to the compressor 40c becomes the target air amount while the push-in blower 30 is stopped. Function.

On the contrary, when the amount of heat exchange in the first heat exchanger 5 decreases and the amount of air detected by the flow meter Sq decreases below the target amount, the opening degree of the damper 32 is increased and air is supplied from the bypass path 35. It is also possible to increase the amount of air supplied to the road 34. It may be configured to control both the damper 32 and the damper 52 at the same time.

When the amount of heat exchanged by the first heat exchanger 5 decreases and the amount of air detected by the flow meter Sq decreases below the target amount, the control unit 70 determines the amount of air blown by the auxiliary push-in blower 30a described above. By simultaneously performing the increase control and the suppression control of the bypass amount with respect to the first heat exchanger 5 by the heat input amount adjusting mechanism 50, the responsiveness of the control can be further improved.

Further, when the amount of heat exchanged by the first heat exchanger 5 increases and the amount of air detected by the flow meter Sq rises above the target amount, the amount of air blown by reducing the opening degree of the damper 32 described above. By simultaneously performing the reduction control of the above and the increase control of the bypass amount with respect to the first heat exchanger 5 by the heat input amount adjusting mechanism 50, the responsiveness of the control can be further improved.

As described above, the operation method of the waste treatment facility according to the present invention is executed by the control unit 70, and the push blower 30 is maintained in a state where the supply amount of combustion air to the fluidized bed incinerator 2 is maintained at a predetermined amount. When the required air volume reaches the preset lower limit air volume, the push blower 30 is stopped, and when the required air flow exceeds the lower limit air volume while the push blower 30 is stopped, the auxiliary push blower 30a is used instead of the push blower 30. It is configured to operate.

Specifically, the auxiliary push-in blower 30a is operated until the required blower amount reaches the start-up blower amount larger than the lower limit blower amount, and when the required blower amount exceeds the start-up blower amount, the push-in blower 30a is replaced with the auxiliary push-in blower 30a. To operate.

Further, the amount of heat input to the turbine 40t is adjusted via the heat amount adjusting mechanism 50 so that the amount of air supplied to the compressor 40c becomes the target amount of air.

Hereinafter, another embodiment of the waste treatment equipment and the operation method thereof according to the present invention will be described. In the above-described embodiment, an example in which both the air blower amount adjusting mechanism and the heat input amount adjusting mechanism 50 by the auxiliary push-in blower 30a have been described has been described. The adjusting mechanism 50 may not be provided.

When the heat input adjusting mechanism 50 is provided, as shown in FIG. 3, a second heat exchanger 4 that adjusts the temperature of the preheated air sent from the turbine 40t when the heat input adjusting mechanism 50 is operated is provided. It is preferable to have.

Then, a bypass path 61 is provided in the flow path for guiding the preheated air sent from the turbine 40t to the second heat exchanger 4, and the bypass path 61 is provided with a temperature adjusting mechanism 60 provided with a damper mechanism as the flow rate adjusting mechanism 62. It is preferable that the combustion air obtained by merging the air heated by the second heat exchanger 4 and the air passing through the bypass path 61 is supplied to the fluidized bed incinerator 2.

In this case, a temperature sensor St is provided in the supply unit of combustion air to the fluidized bed incinerator 2, and the control unit 70 controls the flow rate adjusting mechanism 62 so that the temperature detected by the temperature sensor St becomes the target temperature. It is preferable that the structure is as follows.

The heat input adjusting mechanism 50 operates, and the temperature of the preheated air sent from the turbine 40t and guided to the fluidized bed incinerator 2 as combustion air fluctuates, which hinders the stable operation of the fluidized bed incinerator 2. Even if there is a risk of this, the provision of the second heat exchanger 4 makes it possible to adjust the temperature of the preheated air sent out from the turbine 40t and guided to the fluidized bed incinerator 2 to an appropriate temperature.

Further, as shown in FIG. 4, in order to adjust the temperature of the combustion air supplied to the fluidized bed incinerator 2, the most downstream along the flow direction of the exhaust gas flowing through the heat transfer tube arranged in the second heat exchanger 4. Air inflow portions 4a and 4b for supplying combustion air are provided at two locations on the side and on the upstream side of the most downstream side, and in the flow path 71 for guiding the air sent from the turbine 40t to the second heat exchanger 4. , A damper mechanism as a flow rate adjusting mechanism 72 for adjusting the amount of air flowing in from the air inflow portion 4a and the air inflow portion 4b may be provided.

Also in this case, the temperature sensor St is provided in the supply unit of the combustion air to the fluidized bed incinerator 2, and the control unit 70 controls the flow rate adjusting mechanism 72 so that the temperature detected by the temperature sensor St becomes the target temperature. It may be configured to do so.

As shown in FIG. 5, the configuration of the heat input adjusting mechanism 50 is not limited to the configuration shown in FIG. 1, and a part of the air sent from the compressor 40c and guided to the first heat exchanger 5 is directly transferred to the turbine 40t. It may be composed of a bypass path 51 leading to the transmission port side of the above and a damper mechanism as a flow rate adjusting mechanism 52 provided in the bypass path 51.

As a result of indirectly adjusting the amount of air guided to the first heat exchanger 5 by the flow rate adjusting mechanism 52 provided in the bypass path 51, the amount of heat input to the turbine 40t is adjusted. The preheated air sent from the turbine 40t and the air guided to the bypass path 51 merge and are supplied to the fluidized bed incinerator 2 as combustion air.

As shown in FIG. 6, the heat input adjusting mechanism 50 includes a bypass path 51 that directly guides a part of the preheated air sent from the first heat exchanger 5 to the introduction port of the turbine 40t to the delivery port side of the turbine 40t. , The damper mechanism as the flow rate adjusting mechanism 52 provided in the bypass path 51 may be configured.

It should be noted that any flow rate adjusting mechanism is not limited to the example of adopting the damper mechanism, and it goes without saying that a known flow rate adjusting mechanism such as a valve mechanism can be appropriately adopted.

The entire amount of air sent out from the compressor 40c is guided to the first heat exchanger 5, and a part of the air preheated by the first heat exchanger 5 is guided to the bypass path 51 via the flow rate adjusting mechanism 52. As a result of the residue being guided to the turbine 40t, the amount of heat input to the turbine 40t is adjusted. The preheated air sent from the turbine 40t and the preheated air guided to the bypass path 51 merge and are supplied to the fluidized bed incinerator 2 as combustion air.

In the embodiment shown in FIGS. 3 and 4, an example in which the second heat exchanger 4 is arranged on the upstream side along the flue 10 and the first heat exchanger 5 is arranged on the downstream side thereof has been described. , As shown in FIG. 7, the second heat exchanger 4 and the first heat exchanger 5 arranged in the flue 10 may be arranged so as to be arranged in parallel along the flow direction of the exhaust gas.

In the above-described embodiment, an example in which the first heat exchanger 5 is arranged in the flue 10 and is configured to preheat the combustion air by the retained heat of the exhaust gas guided to the flue has been described. The exchanger 5 may be provided in the flue type incinerator 2 and may be configured to preheat the combustion air by the combustion heat in the furnace.

In the above-described embodiment, the case where the fluidized bed incinerator 2 is adopted as the heat treatment furnace has been described, but the incinerator to which the present invention is applied is not limited to the fluidized bed incinerator 2, and is not limited to the fluidized bed incinerator 2. Similarly, it can be applied to other types of industrial furnaces such as shaft furnaces having a large ventilation pressure loss. For example, a heat treatment furnace or scrap that melts by throwing sludge from above a shaft furnace having a coke bed formed at the bottom and a tuyere for supplying combustion air to the coke bed is thrown in and melted. The present invention can be applied even to a cupola or the like.

The plurality of embodiments described above may be combined as appropriate. For example, the waste treatment facility may be configured by combining the heat input amount adjusting mechanism 50 shown in FIGS. 5 and 6 and the second heat exchanger 4 shown in FIGS. 3 and 4.

Each of the above-described embodiments is an example of the present invention, and the present invention is not limited by the description thereof. Needless to say, it may be appropriately modified and designed within the range in which the action and effect are exhibited.

100: Waste treatment equipment 2: Fluidized bed incinerator (heat treatment furnace)
3: Air supply mechanism 4: Second heat exchanger 5: First heat exchanger 10: Flue 30: Push-in blower 30a: Auxiliary push-in blower 31, 32, 33: Damper 40: Supercharger 40c: Compressor 40t: Turbine 50: Heat input adjusting mechanism 51: Bypass path 52: Flow rate adjusting mechanism (damper mechanism)
70: Control unit 75: Inverter

Claims (11)

A heat treatment furnace that incinerates waste such as sludge,
A first heat exchanger that preheats the combustion air by the combustion heat in the furnace and / or the retained heat of the exhaust gas guided to the flue.
A supercharger including a turbine rotated by combustion air preheated by the first heat exchanger and a compressor that supplies combustion air to the first heat exchanger by rotation of the turbine.
A push-in blower that supplies combustion air to the compressor,
It is a waste treatment facility equipped with
A waste treatment facility including an auxiliary push blower that supplies air to an air supply path from the push blower to the compressor with a lower power than the push blower. The waste treatment facility according to claim 1, further comprising a control unit that stops the push blower when the required blow rate to be supplied to the compressor by the push blower reaches a preset lower limit blower. The waste treatment equipment according to claim 2, wherein the control unit operates the auxiliary push-in blower when the required blower amount exceeds the lower limit blower amount while the push-in blower is stopped. The control unit operates the auxiliary push-in blower until the required blower reaches a start air amount larger than the lower limit blower, and when the required blower exceeds the start-up blower, the auxiliary push-in blower is used. The waste treatment facility according to claim 3, wherein the push-in blower is operated instead. The waste treatment facility according to any one of claims 1 to 4, further comprising an heat input adjusting mechanism for adjusting the heat input of combustion air supplied to the turbine. The waste treatment facility according to claim 5, wherein the heat input adjusting mechanism is composed of a flow rate adjusting mechanism provided in an air supply path to the compressor. The waste treatment facility according to claim 6, wherein the flow rate adjusting mechanism is provided in a bypass path that bypasses the indentation blower. The waste treatment facility according to any one of claims 1 to 7, further comprising a second heat exchanger that adjusts the temperature of the preheated air sent from the turbine by the retained heat of the exhaust gas. A heat treatment furnace that incinerates waste such as sludge,
A first heat exchanger that preheats the combustion air by the combustion heat in the furnace and / or the retained heat of the exhaust gas guided to the flue.
A supercharger including a turbine rotated by combustion air preheated by the first heat exchanger and a compressor that supplies combustion air to the first heat exchanger by rotation of the turbine.
A push-in blower that supplies combustion air to the compressor,
An auxiliary push blower that is connected in parallel with the push blower and has a lower power than the push blower that supplies air to the compressor.
It is a method of operating a waste treatment facility equipped with
When the required amount of air to be supplied to the compressor by the indentation blower reaches a preset lower limit air amount while the amount of combustion air supplied to the heat treatment furnace is maintained at a predetermined amount, the indentation blower is stopped. A method of operating a waste treatment facility that operates the auxiliary indentation blower when the required air amount exceeds the lower limit air amount in a state where the indentation blower is stopped. The auxiliary push-in blower is operated until the required blower amount reaches a start air amount larger than the lower limit blower amount, and when the required blower amount exceeds the start-up blower amount, the push-in blower is replaced with the auxiliary push-blower. 9. The method of operating the waste treatment facility according to claim 9. The waste treatment facility is further equipped with a heat input amount adjusting mechanism for adjusting the heat input amount of the combustion air supplied to the turbine.
The disposal according to claim 9 or 10, wherein the heat input amount of the combustion air supplied to the turbine is adjusted via the heat input amount adjusting mechanism so that the combustion air amount supplied to the compressor becomes the target air amount. How to operate the material processing equipment.

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