JP3907514B2 - Waste heat detection device and waste supply control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention mainly relates to a waste heat detection device for detecting the amount of heat stored in a hopper attached to an incinerator for incinerating municipal waste, industrial waste, etc., and a waste supply control device using the waste heat detection device. It is about.
[0002]
[Prior art]
In general, incinerators that incinerate municipal waste and industrial waste are equipped with hoppers, and dust etc. are picked up by a crane, put into the hopper, and then a dust feeder installed at the bottom of the hopper By this, it is supplied to the incinerator sequentially. Here, there is a pusher type as a type often used as a dust feeding device, and a stoker furnace as a type often used as an incinerator.
[0003]
By the way, the combustion state in an incinerator changes greatly with the amount of heat of the waste supplied to this incinerator, especially the amount of water contained in the waste. For example, if waste with a lot of moisture is supplied into the incinerator, the temperature of the furnace will drop rapidly, leading to an increase in the generation of dioxins, CO, and unburned materials. In this case, the temperature of the furnace rises, causing an increase in the generation of NOx and the like and damage to the furnace.
[0004]
Therefore, in order to suppress the generation of dioxins, CO, NOx, and unburned substances and prevent damage to the incinerator, the temperature in the furnace, CO, The generation of NOx, dioxin, etc. is detected, and based on this information, the amount of primary combustion air blown in the incinerator, the distribution of primary combustion air to each stoker stage (in the case of a stoker-type incinerator), or secondary combustion air A method is adopted in which combustion control such as adjusting the amount of blow is performed to achieve stable combustion inside the incinerator.
[0005]
Also, a method is known in which a load cell is provided in the lower part of the hopper, the weight of the dust in the hopper is measured, and the dust feeder is controlled so that the supplied weight is constant to achieve stable combustion in the incinerator. Yes.
[0006]
[Problems to be solved by the invention]
However, the temperature inside the incinerator or the generation of CO, NOx, dioxin, etc. is detected by a sensor or the like provided in the apparatus on the downstream side of the incinerator, and based on these information, the inside of the incinerator is detected. By controlling the combustion in the furnace and realizing stable combustion in the furnace, it grasps all the many factors such as the temperature in the furnace, the generation of CO, NOx, dioxin, etc., and comprehensively collects such information It is extremely complicated and difficult to control a large number of devices and adjust the amount of primary combustion air blown in, the distribution of this primary combustion air to each combustion stage, or the amount of secondary combustion air blown in, etc. Need to do.
[0007]
In addition, such combustion control is data that cannot be used as an index, such as furnace temperature detected by various sensors provided in an incinerator or a device downstream thereof, information indicating the generation of CO, NOx, dioxin, etc. Therefore, it is extremely difficult to adapt to the quality of the waste stored in the hopper (located upstream of the stoker furnace). As a result, in some cases, combustion control that is not suitable for the quality of the supplied waste may be performed, and there is a problem that reliable stable combustion cannot be realized in the incinerator.
[0008]
Further, according to a method in which a load cell is provided at the lower part of the hopper, the weight of dust in the hopper is measured by this load cell, and the dust feeding device is controlled so that the supply weight becomes constant, the hopper is supported at several places. Therefore, there is a problem that the overall size of the apparatus is inevitably increased, leading to an increase in cost.
[0009]
The present invention has been made to solve such problems, and can detect the amount of heat of dust stored in a hopper serving as an index for downstream control without causing an increase in the size of the apparatus. Providing a debris calorific value detection device and realizing stable combustion with excellent reliability in an incinerator by a simple method to prevent the generation of dioxins and CO in the furnace and the increase of unburned substances An object of the present invention is to provide a waste supply control device that can perform the above.
[0010]
[Means for solving the problems and actions / effects]
In order to achieve the above object, a waste heat quantity detection device according to the first invention comprises:
Waste pressure detection means for detecting the pressure of the waste in the hopper by detecting the lateral pressure of the waste stored in the hopper or the amount of distortion of the hopper wall caused by the waste stored in the hopper;
Level detecting means for detecting the level of dust stored in the hopper;
The apparatus further comprises waste heat amount calculating means for calculating the amount of waste heat based on the pressure of the dust detected by the dust pressure detecting means and the level of dust detected by the level detecting means.
[0011]
According to the waste heat amount detection device of the present invention, the waste pressure detection means detects the pressing force of the waste stored in the hopper as the side pressure or the distortion amount of the hopper wall. At the same time, the level of the dust stored in the hopper is detected by the level detection means provided above the hopper. Next, based on the pressure and level of the dust in the hopper detected in this way, the waste heat amount calculating means calculates the waste heat amount.
[0012]
Since the data indicating the amount of waste heat calculated as described above is calculated based on information inside the hopper, information related to the amount of waste heat can be obtained in real time. Therefore, for example, when used as an index in various controls performed downstream from the inside of the hopper, such as supply control performed by a dust feeder provided in the lower part of the hopper and combustion control performed in the incinerator, And the stable combustion in an incinerator can be implement | achieved reliably.
[0013]
In addition, the dust pressure detecting means can be easily applied to existing equipment such as a method of making a hole in the wall portion of the hopper and attaching a side pressure sensor to the hole, or a method of attaching a conventionally known strain gauge to the outer wall portion of the hopper. Therefore, the entire incineration facility is not increased in size and is excellent in cost.
[0014]
Next, a waste supply control apparatus according to the second invention is:
A waste supply control device configured to supply the waste introduced into the hopper into the incinerator from the lower part of the hopper by means of feeding.
Waste pressure detection means for detecting the pressure of the waste in the hopper by detecting the side pressure of the waste stored in the hopper or the amount of strain in the hopper wall caused by the waste stored in the hopper;
Level detecting means for detecting the level of dust stored in the hopper;
Based on the pressing force of the dust detected by the dust pressure detecting means and the level of the dust detected by the level detecting means, the specific gravity of the waste stored in the hopper is calculated, and based on this specific gravity, per unit time Control means for controlling the dust supply means is provided so that the amount of waste heat supplied into the incinerator is constant.
[0015]
According to the waste supply control apparatus of the second aspect of the invention, the waste pressure detection means detects the pressing force of the dust inside the hopper as a side pressure or a distortion amount of the hopper wall, and at the same time, a level detection means provided above the hopper. Thus, the level of dust stored in the hopper is detected. Next, the specific gravity of the waste is calculated based on the pressure and level of the waste by the control means, and based on the specific gravity of the waste, the amount of waste heat actually stored in the hopper is detected, and per unit time. The dust supplying means is controlled so that the amount of waste heat supplied into the incinerator is constant.
[0016]
That is, according to the waste supply control device of the second invention, the amount of waste heat is detected in real time, and the dust supply means provided downstream from the inside of the hopper is controlled based on the detected value, so that the amount of waste heat is fluctuated. In contrast, waste supply control and combustion control can be realized in real time, and generation of CO, dioxin, NOx, and the like can be suppressed.
[0017]
In addition, according to the supply control device according to the second aspect of the present invention, since the only control means such as the dust supply means is controlled based on the single information such as the amount of waste heat, a large amount of conventional information is comprehensively processed. However, stable combustion in the incinerator can be easily realized as compared with a method of controlling combustion by adjusting a large number of devices.
[0018]
In the second aspect of the invention, the dust supply means includes a pusher that pushes out dust by reciprocating motion, and the control means controls the supply amount of dust by controlling either the speed or the stroke of the pusher. It is preferable (third invention). In this way, when a device using a pusher is employed as the dust supply means, the waste supply control can be performed by controlling either one or both of the operation speed and the stroke of the pusher device.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Next, specific embodiments of the waste heat detection device and the waste supply control device according to the present invention will be described with reference to the drawings.
[0020]
FIG. 1 is a schematic configuration diagram of a waste heat amount control device according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of a side pressure sensor attached to a hopper, and FIG. The flowchart which shows the control flow of the dust feeder which concerns is shown, respectively.
[0021]
In the present embodiment, a stoker-type incinerator 1 for incinerating garbage and the like is provided, and the incinerator 1 is provided with a hopper 2 for storing garbage. In addition, a dust supply device 4 is installed at the uppermost stream portion of the stepped stalker 3 including a dry stalker 3a, a combustion stalker 3b, and a post-combustion stalker 3c.
[0022]
The dust supply device 4 is a pusher type (reciprocating type) device, and a pusher (dust supply device) 6 reciprocated along the flat upper surface of the step 5 and a drive for reciprocating the pusher 6. And a mechanism 7. In this way, garbage thrown from above the hopper 2 by a crane (not shown) is sequentially dropped onto the step 5, and the dust on the step 5 is sequentially cut out onto the drying stoker 3 a by the reciprocating motion of the pusher 6.
[0023]
A plurality of holes are formed in the side surface of the hopper 2, and the pressing force generated by the dust stored in the hopper 2 is detected in the form of a lateral pressure for each hole, and the side pressure of the dust is detected. A side pressure sensor (corresponding to the dust pressure detecting means in the present invention) 8 for continuously transmitting the corresponding electrical signal is attached (only two locations are shown in the figure). On the other hand, above the hopper 2, the distance to the surface of the trash is measured by projecting a laser beam onto the surface of the trash and receiving the reflected light, and from this distance and the shape of the hopper 2 into the hopper. A plurality of laser type level meters 9 having a function of detecting the level of stored dust and transmitting an electric signal corresponding to the detected level of dust are arranged.
[0024]
Outside the hopper 2, there is provided a control means (controller) 10 that is electrically connected to the drive mechanism 7, the side pressure sensors 8, 8, 8... And the level meters 9, 9, 9. In the control means 10, electrical signals transmitted from the side pressure sensors 8, 8, 8... And the level meters 9, 9, 9... Are received, and based on these signals, data processing is performed according to the flow described later, and the dust feeder 4 The control signal for the drive mechanism 7 is calculated and the control signal is output to the drive device 7.
[0025]
As shown in FIG. 2, the side pressure sensor 8 transmits a pressure sensing unit 11 that senses the side pressure and an electric signal corresponding to the side pressure detected by the pressure sensing unit 11 to the control unit 10. It is comprised with the transmission part 12. FIG.
[0026]
The pressure-sensitive part 11 includes a ring-shaped base plate 13, a holding ring 14 disposed on the inner peripheral surface of the base plate 13, a diaphragm 15 attached by the base plate 13 and the holding ring 14, A back cover 16 that is screwed to the base plate 13 and is attached so as to cover the diaphragm 15, a pressure receiving rod 17 that is pivotally attached to an attachment portion that protrudes inside the back cover 16, and the pressure receiving rod A disc-shaped pressure receiving plate 18 attached to the other end of the cylinder 17; a cylinder 19 having one end attached to the pressure receiving rod 17 and the other end attached to the transmitting portion 12 so as to pass through the opening provided in the back cover 16; The pressure receiving rod 17 and the pressure receiving plate 18 are constituted by a return spring 20 attached to the back cover 16 so as to apply an urging force in the direction of the diaphragm 15. The urging force of the return spring 20 is adjusted so that the surface of the pressure receiving plate 18 is in close contact with the diaphragm 15.
[0027]
On the other hand, the transmitter 12 to which the other end of the cylinder 19 is attached continuously transmits a steady electric signal. When the cylinder 19 expands and contracts, the transmitter 19 immediately senses the degree of expansion and contraction and sends an electric signal corresponding to the degree of expansion and contraction. An electric signal transmitter 21 for transmitting and a casing (not shown) that covers and fixes the electric signal transmitter 21 are provided, and in this casing, an output portion of an electric signal transmitted from the electric signal transmitter 21 (see FIG. Not shown). The output unit (not shown) is connected to the control means 10 via an electric line.
[0028]
The side pressure sensor 8 configured as described above is fixed by being screwed from the outside of the hopper so that the diaphragm 15 protrudes slightly inside the hopper 2 in each hole formed in the hopper 2. ing.
[0029]
The side pressure sensors 8, 8, 8... Attached to the hopper 2 in this way have no urging force in the hopper 2, that is, the urging force due to the side pressure of the trash is applied to the diaphragm 15 and the pressure receiving plate 18 that is in close contact therewith. When it does not act, a stationary electrical signal is output from the electrical signal transmitter 21 to the control means 10.
[0030]
From this state, when the diaphragm 15 and the pressure receiving plate 18 are pressed by the biasing force due to the side pressure, and the cylinder 19 is pressed accordingly, the degree of expansion / contraction of the cylinder 19 is immediately detected by the electric signal transmitter 21. An electric signal corresponding to the degree of expansion / contraction is output to the control means 10. In this way, an electric signal corresponding to the side pressure in the hopper 2 is continuously transmitted to the control means 10.
[0031]
On the other hand, also in the level meter 9, an electric signal corresponding to the level of the dust in the hopper 2 detected based on the distance to the surface of the dust measured by projecting and receiving the laser beam and the shape of the hopper is controlled. 10 is continuously transmitted.
[0032]
The control means 10 performs data processing according to the flow described later, based on the electrical signal indicating the side pressure received from the side pressure sensors 8, 8, 8... And the electrical signal indicating the level received from the level meters 9, 9, 9. Then, the amount of waste heat in the hopper is calculated, and a control signal for the drive mechanism 7 of the dust feeder 4 is calculated so that the amount of waste heat supplied per unit time is constant, and this control signal is calculated as the drive device 7. Is output. The driving device 7 adjusts the feeding speed of the pusher 6 based on this control signal, and controls the amount of dust supplied from the pusher 6 to the dry stoker 3a.
[0033]
Next, the control flow of the dust feeder 4 in this embodiment will be described in detail with reference to the flow shown in FIG.
[0034]
S1: In each of the side pressure sensors 8, 8, 8,... Attached to the side surface of the hopper 2, the pressing force of the dust stored in the hopper 2 is detected in the form of a side pressure, and an electric signal corresponding to the pressure is detected. It transmits to the control means 10. At the same time, in each of level meters 9, 9, 9... Provided above the hopper 2, the level of dust stored in the hopper 2 is detected, and an electric signal corresponding to the measurement result is detected by the control means. 10 to send.
S2: In the control means 10, the average side pressure of the garbage is calculated based on the electric signal corresponding to the side pressure received from each of the side pressure sensors 8, 8, 8... The average level of waste is calculated based on the corresponding electrical signal.
S3: In the control means 10, the correlation between the average side pressure of the garbage stored in the hopper 2 obtained in the previous step S2 and the side pressure and weight of the garbage input to the control means 10 in advance is obtained. Based on the indicated data (actual measurement data), the weight of the waste stored in the hopper 2 is calculated.
S4: Based on the average level of the waste stored in the hopper 2 obtained in step S2 and the data indicating the shape of the hopper input in advance, the volume of the waste stored in the hopper 2 is calculated. To do.
S5: The specific gravity of the waste stored in the hopper 2 is calculated based on the weight and volume of the waste stored in the hopper 2 calculated in steps S3 and S4, respectively.
[0035]
S6: Based on the specific gravity of the dust calculated in the previous step S5 and the actual measurement data indicating the correlation between the specific gravity of the dust and the amount of waste heat input to the control means 10 in advance, the waste is actually stored in the hopper 2. Calculate the amount of heat in the garbage.
S7: Based on the amount of dust supplied by one stroke of the pusher 6, the number of reciprocations (powder supply speed) of the pusher 6 such that the amount of dust heat supplied into the stalker 3 per unit time is constant is calculated. .
S8: A control signal is output to the drive mechanism 7 of the pusher 6 based on the calculated feed speed.
[0036]
By executing such control, the amount of heat of the waste supplied to the incinerator 1 per unit time can be made constant, and thus stable combustion can be realized in the incinerator 1. In this way, it is possible to reduce the generation of CO, prevent the generation of unburned substances, and further suppress the generation of dioxins.
[0037]
Further, in the present embodiment, stable combustion of the incinerator is realized by controlling only one supply control means such as a dust supply device based on the only information of the amount of heat detected in the hopper 2. . Therefore, based on various factors such as furnace temperature, CO, dioxin, NOx, etc., various devices are controlled to blow the primary combustion air, distribute the primary combustion air to each stoker stage, or secondary Combustion control can be performed by an extremely simple method as compared with the conventional method in which the amount of combustion air blown in is adjusted to achieve stable combustion in the incinerator.
[0038]
Moreover, in this embodiment, the information used for control (the amount of waste heat stored in the hopper 2) is detected upstream of the means for supplying control (the dust supply device). Information is used as an indicator of supply control. Therefore, the supply control apparatus according to the present embodiment can realize stable combustion in the combustion furnace more reliably than the conventional method of performing the upstream combustion control based on the downstream information. .
[0039]
In the present embodiment, this can be realized by making a hole in the existing hopper 2 and attaching a side pressure sensor to the hole, so that the device itself does not increase in size, and can be reliably and inexpensively disposed of in the hopper. The amount of heat can be calculated.
[0040]
In the present embodiment, the contact-type side pressure sensor 8 is used to detect the pressing force of the dust inside the hopper 2 as the side pressure, but instead of using the side pressure sensor 8, the attached portion is used. Alternatively, a conventionally known strain gauge using a piezoresistive effect in which the resistance value changes due to the occurrence of strain may be used. In such a case, a plurality of strain gauges are bonded to the outside of the hopper 2, the strain amount of the hopper 2 itself due to the dust stored therein is detected by the strain gauge, and the detected strain amount is used as an electric signal to control means. 10 is transmitted continuously. Then, the control means 10 calculates the average value of the strain amount, and based on the average value of the strain amount, the average value of the dust level (detected from the level meter 9), and the measured data, the hopper 2 Try to find the specific gravity of the waste inside.
[0041]
Even in such a case, from the specific gravity of the waste stored in the hopper, the number of reciprocations of the pusher 6 that makes the amount of heat of the waste and the amount of waste heat supplied into the stalker 3 per unit time constant ( (Feeding speed) can be calculated. In this way, stable combustion can be realized in the incinerator 1. Since this strain gauge does not directly contact the dust inside the hopper, there is an advantage that it is not easily damaged. Further, by attaching to the outer wall of the hopper 2, it is possible to detect the pressing force (strain amount) of the dust, so that the strain gauge can be easily exchanged, and there is an advantage in terms of maintenance. Moreover, since the existing hopper can be used as it is, it is advantageous in terms of cost.
[0042]
In each of the above embodiments, the operation speed of the pusher 6 is controlled to control the supply amount, but the stroke of the pusher 6 may be controlled.
[0043]
In each of the above embodiments, the pusher type feeding means has been described. However, the concept of the present invention can be applied to those using other dusting means (for example, a screw type feeding device). be able to.
[0044]
In each of the above embodiments, the supply control based on the amount of heat of the waste stored in the hopper 2 has been described. However, in conjunction with this, even if the combustion control is performed on the stalker 3 or downstream thereof, good. In such a case, since the amount of heat of the waste supplied from the dust feeder arranged upstream is detected in advance, combustion control may be performed using the amount of waste heat as an index, and more reliable and stable combustion can be easily performed. Can be realized.
[Brief description of the drawings]
FIG. 1 is a schematic explanatory diagram of a waste supply control apparatus according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of a side pressure sensor according to an embodiment.
FIG. 3 is a flowchart showing a control flow of the dust feeder in one embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Incinerator 2 Hopper 3 Stair type stalker 4 Dust feeder 6 Pusher 7 Drive mechanism 8 Side pressure sensor 9 Level meter 10 Control means

Claims (3)

Waste pressure detection means for detecting the pressure of the waste in the hopper by detecting the lateral pressure of the waste stored in the hopper or the amount of distortion of the hopper wall caused by the waste stored in the hopper;
Level detecting means for detecting the level of dust stored in the hopper;
A waste heat amount detecting device, comprising: a waste heat amount calculating means for calculating a waste heat amount based on a pressing force of the waste detected by the waste pressure detecting means and a level of the waste detected by the level detecting means. . A waste supply control device configured to supply the waste introduced into the hopper into the incinerator from the lower part of the hopper by means of feeding.
Waste pressure detection means for detecting the pressure of the waste in the hopper by detecting the side pressure of the waste stored in the hopper or the amount of strain in the hopper wall caused by the waste stored in the hopper;
Level detecting means for detecting the level of dust stored in the hopper;
Based on the pressing force of the dust detected by the dust pressure detecting means and the level of the dust detected by the level detecting means, the specific gravity of the waste stored in the hopper is calculated, and based on this specific gravity, per unit time A waste supply control device comprising a control means for controlling the dust supply means so that the amount of waste heat supplied into the incinerator is constant. 3. The dust supply means includes a pusher that pushes out dust by reciprocating motion, and the control means controls a supply amount of dust by controlling either a speed or a stroke of the pusher. The garbage supply control device described in 1.

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