JP4097595B2 - Combustion accelerator - Google Patents

Description

  The present invention relates to a combustion accelerating device for accelerating combustion of an object to be treated such as municipal waste used in a garbage incineration plant or the like. More specifically, the present invention relates to a combustion promoting device (stoker-type waste incinerator) for stably burning low-heat generation waste with a lot of moisture.

  Most of the municipal waste discharged in daily social life is collected in a garbage incineration plant and incinerated. The heat generated when garbage is incinerated may be used as a heat source for heating or as an energy source for power generation.

  However, municipal garbage is difficult to burn stably because its properties and components are not constant, and it is generally difficult to use such municipal garbage as a regular energy source. For example, there is a tendency for large amounts of low calorific value garbage such as household waste with a lot of moisture to be generated in the summer, and if such low calorific value garbage is mixed in a large amount of ordinary general garbage, it may cause combustibility deterioration. . If the flammability of garbage deteriorates, facilities that use waste heat of combustion as an energy source cannot obtain a sufficient amount of heat due to combustion, which causes problems in equipment operation. There is a fear. Moreover, if the combustion of waste is insufficient, unburned waste will remain as impurities in the incineration ash generated after waste incineration, and such impurities will adversely affect post-treatment such as landfill disposal. Effect. Therefore, a technology for stably burning municipal waste without being affected by the properties and components of the waste is desired from the waste treatment industry.

  By the way, a typical incinerator used in a garbage incinerator or the like is a stoker type incinerator. A stoker-type incinerator generally includes a dust supply device that supplies garbage, a dry stoker that dries the garbage, a combustion stoker that burns the dried garbage, and the like. In a conventional stoker-type incinerator, in order to control the combustion state of garbage, the temperature in the furnace, the amount of steam generated, etc. are measured, or the combustion state of garbage is monitored as an image with a monitoring camera. Measures such as adjusting the amount of dust supplied from the dust supply device, or changing the dust carrying capacity by changing the operating stroke length of the stalker, have been executed.

  For example, in the stoker type garbage incinerator disclosed in Patent Document 1, when it is determined that an excessive amount of dust is supplied onto the combustion stoker, the combustion state becomes insufficient and the predetermined combustion temperature has not been reached. The working length of the combustion stoker is shortened, and the dust conveying force is reduced while maintaining the dust stirring action to some extent. Specifically, in the stoker-type garbage incinerator of Patent Document 1, when an appropriate amount or less of garbage is supplied onto the combustion stoker and these are maintaining a sufficient combustion state, the operation stroke length of the combustion stoker is increased. However, if the dust is excessively supplied onto the combustion stoker and the combustion state becomes insufficient and a sufficient combustion temperature cannot be achieved, the operating stroke length of the combustion stoker is increased. By shortening it, the transporting power of garbage is reduced, and the burning time of garbage is being secured for a long time.

  Further, in the stoker type garbage incinerator disclosed in Patent Document 2, when the amount of dust on the combustion stoker becomes excessive, the dust carrying speed of the dry stoker is reduced, and the movement of the dust from the dry stoker to the combustion stoker is limited. In this way, the combustion state of garbage is recovered. Specifically, the stoker-type garbage incinerator of Patent Document 2 increases the operating speed of the dry stoker when a proper amount of garbage is supplied onto the combustion stoker and maintains a sufficient combustion state. However, if there is an excessive amount of dust on the combustion stalker and sufficient combustion cannot be ensured, the operating speed of the dry stalker can be reduced. In this way, the movement of garbage to the combustion stalker is restricted, and the combustion capacity of the combustion stalker is given a margin so that the garbage is not unburned.

  On the other hand, Patent Document 3 discloses a stoker-type incinerator in which a dry stoker and a combustion stoker are integrated. In the stoker-type incinerator of Patent Document 3, the amount of evaporation during garbage combustion is monitored. If it is determined from the amount of evaporation that the dust on the stoker is low-calorific value dust, a feeder and The stalker is stopped at the same time, and the garbage burning time on the stalker is secured. Then, after a certain time has elapsed since the stop, the operation of the feeder and the stoker is restored.

Japanese Patent No. 2624912 JP-A-9-273731 JP-A-7-260126

  However, in the stoker type garbage incinerator disclosed in Patent Document 1, the stroke length of the combustion stoker is shortened as a measure when the dust is excessively supplied onto the combustion stoker and the combustion state becomes insufficient. Therefore, there is a problem that the stirring action of dust cannot be increased so much and it takes time to recover the combustion state. In such a method, even if the operating speed of the stalker is increased, the stroke length remains small, so that a significant improvement in the stirring effect cannot be expected. Therefore, the stoker-type garbage incinerator disclosed in Patent Document 1 has not completely solved the problem of improving the combustion state of garbage.

  Further, in the stoker type garbage incinerator disclosed in Patent Document 2, the combustion stoker always repeats the same operation, so even if the amount of movement of dust from the dry stoker to the combustion stoker increases, The agitation action of the dust does not improve, and in particular, when there is a lot of dust with a lot of water or dust with poor air permeability, early recovery of the combustion state of the dust cannot be expected so much.

  On the other hand, in the stoker-type garbage incinerator disclosed in Patent Document 3, since the dry stoker and the combustion stoker are integrated as described above, the stoker-type waste incinerator still exists on the dry stoker when the operation of the stoker is restored. There is a possibility that unburned garbage that has not been sufficiently dried moves and accumulates on the garbage on the combustion stalker, and the combustion of the garbage in the combustion stalker is hindered.

  As described above, the conventional stoker-type garbage incinerator cannot perform sufficient combustion when garbage with different properties and components (especially garbage with a large amount of water) is mixed, and in addition, it takes time to recover the garbage combustion state. I have a big problem of hanging.

  Accordingly, the present invention has been made in view of the above-mentioned problems, and the object of the present invention is to provide a sufficient amount of dust even when dust with a low calorific value with a large amount of moisture is mixed during the waste incineration process. It is an object of the present invention to provide a combustion acceleration device for a stoker-type garbage incinerator capable of performing the combustion of the above.

  A first characteristic configuration of a combustion promoting device according to the present invention is a combustion promoting device that promotes combustion of an object to be processed, a dust supply unit that supplies the object to be processed onto a dry stoker, and the dry stoker. Drive means for reciprocating a combustion stalker located at the subsequent stage of the dry stalker, detection means for detecting the combustion state of the object to be processed, and the dust supply means and the drive based on the detection result of the detection means Control means for controlling the means, and when the control means determines that there is an excessive amount of unburned material on the combustion stoker, the control means stops the dust supply means and the drive means for a predetermined time. Thereafter, the driving means is controlled so that only the combustion stalker reciprocates at a speed larger than the speed before stopping.

  In the combustion promoting device having the first characteristic configuration, when the control means determines that the unburned material is excessively present on the combustion stalker based on the detection result of the detection means, the control means is the dust supply means. And the driving means is stopped for a predetermined time, and then only the combustion stalker is reciprocated at a speed larger than the speed before the stop, so that when both the drying stalker and the combustion stalker are stopped, It is possible to promote the combustion of garbage on the combustion stoker. And when only the combustion stalker resumes operation, there is no problem that the dust on the dry stalker is deposited on the burning trash on the combustion stalker at once and the combustion of the trash on the combustion stalker is inhibited. It becomes possible to continue stable garbage combustion. When the combustion stalker is switched from the stopped state to the activated state, the combustion stalker operates at a speed higher than the speed before the stop, so that the effect that the dust on the combustion stalker is sufficiently stirred is obtained. Further, it becomes possible to further promote the combustion of garbage on the combustion stoker. In addition, in the combustion promoting device 100 of the present invention, the stable combustion of garbage is possible, so that the burnout point of the garbage on the stoker does not retreat greatly, and a large amount of garbage with undefined properties and components is mixed. Even so, the balance between waste supply and discharge is kept optimal, and as a result, it is possible to stably treat municipal waste.

  In the second characteristic configuration of the combustion promoting device according to the present invention, the number of reciprocating operations of the combustion stalker at a speed larger than the speed before stopping can be arbitrarily set.

  With the combustion promoting device having this second characteristic configuration, the optimum number of reciprocating operations of the combustion stalker can be set according to the combustion state or agitation state of the dust on the combustion stoker, so that the waste can be efficiently burned. And a good combustion state can be maintained.

  In the third characteristic configuration of the combustion promoting device according to the present invention, the speed larger than the speed before the stop may be the maximum reciprocating speed of the combustion stoker.

  With the combustion promoting device having the third characteristic configuration, the combustion stalker can be operated at the maximum reciprocating speed, so that the dust on the combustion stalker is strongly agitated, and the combustion of the dust can be further promoted. It becomes.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, this invention is not limited to the structure described in the following embodiment and drawing.

  FIG. 1 is a schematic view showing a combustion promoting device 100 of the present embodiment in a stoker type garbage incinerator. The combustion promoting apparatus 100 is an apparatus for accelerating the combustion of a combusted object, for example, to-be-treated object such as city garbage or industrial waste. In the present specification, as an object to be processed of the combustion promoting device 100, municipal waste that contains a lot of moisture and whose properties and components are not constant is described as an example. However, the present invention is particularly limited to this. It is not a thing.

  As shown in FIG. 1, the combustion promoting device 100 includes, for example, a dry stoker 1 for drying garbage, a combustion stocker 2 for burning dried garbage, and a post-combustion stoker 3 for burning garbage. A divided stoker type garbage incinerator is constituted, and is provided with a dust supply means 4, a drive means 5, a detection means 7, and a control means 9. Each means constituting the combustion promoting device 100 will be described below.

  The dust supply means 4 is means for supplying the dust put into the hopper 6 onto the dry stalker 1, and for example, a pusher can be used. In the present embodiment, the dust supply means 4 reciprocates with a stroke set by the operator, and dust is pushed out from the bottom of the hopper 6 toward the dry stalker 1 by this action. Further, if the setting of the operation stroke of the dust supply means 4 is changed, the amount of pushing out (supply amount) of dust from the hopper 6 can be changed.

  Of course, the dust supplying means 4 may have a configuration other than the pusher exemplified in the present embodiment. For example, a general-purpose rotary feeder, a vibration feeder or the like can be adopted as the other dust supply means 4.

  The driving means 5 reciprocates the dry stoker 1, the combustion stoker 2 in the subsequent stage, and further the post-combustion stoker 3 in the final stage. For example, as shown in FIG. 2, each stalker is configured to include a plurality of movable grate 20 and fixed grate 21 so that these movable grate 20 and fixed grate 21 are alternately adjacent to each other. Has been placed. Since the movable grate 20 and the fixed grate 21 are made of a material such as heat-resistant steel, for example, the movable grate 20 and the fixed grate 21 can sufficiently withstand the combustion heat of dust. The conveyance of the dust is realized by causing the driving means 5 to drive the movable grate 20 and causing the movable grate 20 to slide between the fixed grate 21 to generate a conveying action on the upper surface of the stoker. When a transport action occurs on the top surface of the stalker, the dust on the top moves to the downstream side of the stalker.

  The drive means 5 may have a configuration in which one dedicated drive means is provided for each stalker so that the dry stalker 1, the combustion stalker 2, and the post-combustion stalker 3 can be driven independently. it can. Alternatively, a common driving unit may be provided for the three stalkers, and a driving force may be distributed from one driving unit to each stalker. As the drive means 5, for example, a mechanism such as a hydraulic cylinder 10 that can extend and contract in the longitudinal direction can be employed.

The detection means 7 is installed in the furnace of the combustion promoting device 100, and can monitor dust burning on the combustion stalker 2 and detect the combustion state. For example, detection of the combustion state of garbage is performed by, for example, furnace outlet temperature, exhaust gas flow rate, exhaust gas O ₂ concentration, flame end position (burn-off point) in the combustion stoker 2, dust layer thickness on the stoker, and air pressure in each zone below the furnace. This is based on parameters such as loss. In the case of the parameters shown here, while the detection means 7 is burning dust, the temperature at the furnace outlet, the exhaust gas flow rate is decreased, the exhaust gas O ₂ concentration is increased, the fuel cut point is decreased, and the dust on the dry stoker 1 or combustion zone stoker 2 is detected. When at least one of the increase in the layer thickness and the increase in the air pressure loss under the furnace is detected, the control means 9 to be described later indicates that the combustion state of the dust is insufficient even though the dust is not insufficient in the furnace. judge.

  As the detection means 7, various sensors, measuring devices, measuring devices, and the like can be appropriately selected according to the structure and scale of the combustion promoting device 100. For example, a temperature sensor, a flow meter, a level meter, a pressure gauge, or the like can be used as the detection means 7. Further, the detection means may be a television camera 11 capable of photographing burning dust, and the photographed video may be analyzed by image processing or the like. The television camera 11 in this case can be used in combination with a garbage incinerator when a monitoring camera for in-furnace monitoring is originally installed.

  The control means 9 controls the dust supply means 4 and the drive means 5 based on the detection result of the dust combustion state by the detection means 7. Specifically, when the control unit 9 receives information on the combustion state of dust from the detection unit 7 and determines that there is an excess of unburned dust on the combustion stalker 2, the control unit 9 stops the dust supply unit 4 and the drive unit 5. Further, the supply of dust from the dust supply means 4 onto the dry stalker 1 and the movement of the dust from the dry stalker 1 onto the combustion stalker 2 are suppressed, the drying time of the trash on the dry stalker 1, and the combustion stalker 2 The burning time of the upper garbage is secured. After the predetermined time has passed and the combustion state of the dust has recovered to some extent, the control means 9 thereafter controls the speed of the combustion stalker 2 alone (for example, 70 to 90 cycles / hour) greater than the speed before the stop (for example, 10 cycles / hour). A control command is transmitted to the driving means 5 so as to reciprocate at the time. At this time, since the combustion stoker 2 performs a strong reciprocating motion, a large dust stirring action is generated on the upper surface of the combustion stoker 2. Thereby, the air permeability of the dust on the combustion stoker 2 is improved, and the dust combustibility is further promoted.

  The control means 9 may be dedicated hardware designed for controlling the dust combustion state, but a personal computer or the like into which a program for performing the above control is installed can also be used.

  Next, a method for controlling the combustion of dust using the combustion promoting device 100 of the present embodiment will be described in more detail.

  FIG. 3 is a flowchart showing a process for controlling the combustion of dust on the combustion stalker 2 by the combustion promoting apparatus 100 of the present embodiment. When the combustion of dust starts, the combustion promoting device 100 enters a state in which the detection means 7 can detect the combustion state of the dust on the combustion stalker 2 (S1). When it is determined that there is no excessive amount of unburned garbage on the combustion stalker 2 in response to the detection result from the detection means 7 (S2: No), the detection state (S1) continues. If it is determined that there is an excessive amount of unburned garbage on the combustion stalker 2 (S2: Yes), the control means 9 stops the dust supply means 4 and the drive means 5 (S3), Burning waste is burned for a predetermined time (S4: Yes). When the predetermined time has not elapsed (S4: No), the combustion is continued as it is. After burning the dust for a predetermined time, the control means 9 operates the driving means 5 to reciprocate only the combustion stalker 2 at a speed larger than the speed before stopping (S5), and stirs the dust on the combustion stalker 2. When the dust is agitated and the combustion state is recovered, the state returns to the detectable state (S1) which is a normal control state.

  When the combustion of dust is performed using the combustion promoting device 100 of the present embodiment through the above-described steps, the following advantages are obtained.

  That is, in the combustion promoting device 100 of the present embodiment, when the control means 9 determines that there is an excess of unburned garbage on the combustion stalker 2 based on the detection result of the detection means 7, the control means 9 The means 4 and the drive means 5 are stopped for a predetermined time. Thereafter, the control means 9 reciprocates only the combustion stalker 2 at a speed higher than the speed before stopping. As a result, when the dust supplying means 4 and the driving means 5 are stopped and both the dry stalker 1 and the combustion stalker 2 are in a stopped state, the dust on the dry stalker 1 is dried and the dust on the combustion stalker 2 is burned. Promoted. Thereafter, only the combustion stalker 2 resumes operation, so that the dust on the dry stalker 1 accumulates on the burning trash on the combustion stalker 2 at once, and the combustion of the trash on the combustion stalker 2 is hindered. Does not happen. In this way, the operation of resuming only the operation of the combustion stalker 2 can prevent the combustion of the dust on the combustion stalker 2 from being inhibited. Therefore, if the dust on the dry stalker 1 is not yet sufficiently dried, the combustion is performed. This is particularly effective because it prevents inflow of undried dust into the stalker 2. Thus, in the combustion promoting apparatus 100 of the present embodiment, it is possible to continue the combustion of dust stably.

  Further, when the combustion stoker 2 is switched from the stopped state to the activated state, the combustion stoker 2 temporarily operates at a speed higher than the speed before the stop for a certain period of time, so that excessive movement of dust to the post-combustion stoker occurs. Therefore, the effect that the dust on the combustion stoker 2 is sufficiently stirred is obtained, and as a result, the combustion of the dust on the combustion stoker 2 can be further promoted.

  Furthermore, in the combustion promoting device 100 of the present invention, stable combustion of dust is possible, so that the burnout point of the dust on the stoker does not retreat greatly, and a large amount of dust with undefined properties and components is mixed. However, the balance between waste supply and discharge is optimally maintained, and as a result, city waste can be treated stably.

  In the above-described dust combustion control process, the number of times of reciprocating operation at a speed larger than the speed before stopping the combustion stalker 2 performed in step 5 can be arbitrarily set. The number of times of setting is sufficient if it is necessary for sufficient air to be mixed in the dust. For example, the dust on the combustion stalker 2 is greatly agitated and burned by a reciprocating operation of about 2 to 3 times. It is possible to sufficiently mix the air required for the trash.

  In the present embodiment, since the optimum number of reciprocating operations of the combustion stalker 2 can be set according to the combustion state or agitation state of the dust on the combustion stoker 2, it is possible to efficiently burn the dust, The combustion state can be maintained.

  The speed larger than the speed before the combustion stoker 2 stops is preferably the maximum reciprocating speed of the combustion stoker 2. Since the degree of dust agitation generally has a correlation with the reciprocating speed of the combustion stalker 2, if the combustion stalker 2 is operated at the maximum reciprocating speed, the dust on the combustion stalker 2 is strongly agitated and the combustion of the garbage is more This can be further promoted.

<< Another Embodiment >>
In the above embodiment, a configuration has been described in which the detection unit detects the dust combustion state, and the control unit controls the dust supply unit and the driving unit based on the detection result. However, the control performed by this control means may be performed directly by a person. That is, the person can recognize the detection result from the detection means by visual observation or the like, and adjust the combustion state of the dust manually by the human hand.

Schematic showing the combustion promoting device of the present invention A perspective view showing the configuration of a stoker including a movable grate and a fixed grate The flowchart which showed the process of the combustion control of the garbage on the combustion stalker by the combustion promotion apparatus of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Dry stalker 2 Combustion stalker 3 Post combustion stalker 4 Dust supply means 5 Drive means 6 Hopper 7 Detection means 8 Blower 9 Control means 10 Hydraulic cylinder 11 Television camera 100 Combustion acceleration device

Claims (3)

A combustion accelerating device for accelerating combustion of a workpiece,
Dust supplying means for supplying the object to be processed onto a dry stoker;
Drive means for reciprocating the dry stalker and a combustion stalker located downstream of the dry stalker;
Detecting means for detecting a combustion state of the workpiece;
And a control means for controlling the dust supply means and the drive means based on the detection result of the detection means, and when the control means determines that an unburned object is excessively present on the combustion stalker, The combustion accelerating device that controls the driving means so that only the combustion stalker reciprocates at a speed larger than the speed before the stop after the control means stops the dust supply means and the driving means for a predetermined time.   The combustion promoting device according to claim 1, wherein the number of reciprocating operations of the combustion stoker at a speed larger than the speed before the stop can be arbitrarily set.   The combustion acceleration device according to claim 1 or 2, wherein a speed larger than the speed before the stop is a maximum reciprocating speed of the combustion stoker.

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