JP3852193B2 - Combustion control method and apparatus for rotary grate furnace - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a rotary grate furnace in which the amount of dust supplied is adjusted so that the combustion state in the furnace is controlled so as to stabilize the waste combustion state of the rotary grate furnace that incinerates municipal waste in a certain range. The present invention relates to a combustion control method and apparatus.
[0002]
[Prior art]
In the rotary grate furnace, as schematically shown in FIG. 25, a large number of water pipes 4 are arranged at regular intervals in the circumferential direction between the inlet side header pipes 2 and the outlet side header pipes 3. Both ends are connected to and communicated with the inlet-side header pipe 2 and the outlet-side header pipe 3, and a furnace wall plate provided with a large number of air holes is attached between the water pipes 4. 1, the grate furnace main body 1 is rotatably accommodated in a cover casing 5, and is inclined and placed so that the outlet side header pipe 3 is lower, and the grate furnace main body 1. The tire 6 is attached to the outer periphery of the inlet side and the outlet side of each of the tires, the tires 6 are respectively placed on the turning rollers 7, and one turning roller 7 is rotated by the motor 8 to thereby adjust the grate furnace body 1 Rotate, and further Garbage to be introduced from an introduction hopper 10 connected to the upstream side by installing a wind box 9 in the lower part of the grate furnace body 1 and introducing air from the wind box 9 through the wall of the grate furnace body 1 11 is put into the grate furnace main body 1 by the pusher device 12, and the garbage 11 is incinerated while rotating the grate furnace main body 1.
[0003]
13 is a post-combustion device, 14 is a secondary combustion chamber, and 15 is a universal joint connected to the outlet side header pipe 3 so as to circulate and circulate boiler water in the water pipe 4.
[0004]
When incineration of garbage is performed in a rotary grate furnace having such a configuration, if the incineration temperature of the garbage is unstable and incomplete combustion occurs, harmful dioxins may be generated.
[0005]
For this reason, incineration of garbage has been devised to ensure that garbage is burned reliably and stably.
[0006]
Conventionally, in the incineration of garbage in the grate furnace main body 1 of the rotary grate furnace, a method of measuring the burning point has been adopted as one of the measures for knowing the combustion state of the garbage. Has been proposed to control the position of the burn-out point by using fuzzy theory so as to stabilize the position of the burnout point.
[0007]
That is, as shown in FIG. 26, in the incineration of the garbage 11 in the grate furnace main body 1, when the location where the flame 16 is generated is in the range shown by the oblique lines, the position of the burnout point 16a which is the lowest point of the flame 16 Is measured in the longitudinal direction (upstream / downstream direction) in the grate furnace body 1, and the rotary grate furnace is used by using fuzzy theory so that the position of the burnout point 16a is stabilized in a certain part. The number of revolutions is controlled, the amount of dust 11 supplied to the rotary grate furnace is controlled, and the like.
[0008]
On the other hand, the amount of waste 11 supplied (rotation amount) to the rotary grate furnace for incineration must be more than a day, or the amount of steam generated by incineration must be constant. There is a standard, and conventionally, the amount of generated steam is adjusted by adjusting the amount of supplied dust according to the set value of the supplied amount, or by introducing it to the water pipe of the boiler or the water pipe 4 of the grate furnace main body 1 to make it constant. In addition, the amount of dust supplied was manually adjusted to stabilize the combustion state in the furnace.
[0009]
[Problems to be solved by the invention]
However, with the former fuzzy inference that controls the rotational speed and feed rate of the rotary grate furnace, the measurement of the burn-off point 16a shown in FIG. 26 indicates that the waste quality and the waste layer are uniform. In fact, due to the effects of non-uniformity of the dust layer and high quality of waste, the change in the spread of dust in the dust layer and the furnace occurs, as shown in FIG. However, even if the distance in the longitudinal direction of the furnace of the burnout point 16a is the same as in FIG. 26, it moves to the right in the circumferential direction, so only the distance in the longitudinal direction of the furnace was measured as the burnout point. However, there is a problem with the detection accuracy of burnout points and the usage range (the stability range of burnout points is narrow), and it is not possible to accurately grasp the combustion status, and conventional combustion pass / fail information based on burnout points is used as a control system. There is a problem that it cannot be reflected.
[0010]
Also, in the latter case where the amount of dust supply is adjusted manually according to the amount of evaporation, the amount of evaporation may vary greatly depending on the quality of the waste such as the calories of the garbage. There is a problem in that the combustion state in the furnace becomes unstable because the amount of dust supplied is adjusted without looking at the combustion index in the furnace.
[0011]
Therefore, in the present invention, instead of measuring the burn-out point, which is the lowest point of the flame, a burning method index and garbage calorie based on the longitudinal and circumferential burning index measured from the position of the center of gravity of the flame By adjusting the supply amount from the evaporation amount based on the fluctuation of the supply amount and controlling the combustion, the accuracy of combustion is improved, and the control accuracy is improved and long-term automatic control of the combustion is achieved. is there.
[0012]
[Means for Solving the Problems]
In order to solve the above problems, the present invention relates to the position of the center of gravity of the flame when the dust supplied into the rotary grate furnace is burned while rotating the grate furnace body, and the circumferential direction of the grate furnace body. Fuzzy rules determine the values of the membership functions of the circumferential and longitudinal burning index by fuzzy calculation so that the center of gravity position is stable within a certain range. All are shown in the membership function of the rotary grate furnace rotation speed and inferred, and the center of gravity of the inference result obtained by synthesizing the membership function of the rotary grate furnace rotation speed is obtained by the centroid method. The Rotary grate furnace As rotational speed correction amount To obtain the rotational speed correction amount of the rotary grate furnace and the rotational speed set value of the rotary grate furnace. While adjusting the rotational speed of the rotary grate furnace, For each flame center of gravity position Rotary grate furnace According to the fuzzy rule when the amount of rotation speed correction is calculated Control result Furnace Then, the values of each of the membership functions of waste calories and feed amount are inferred from the membership function of evaporation for all the fuzzy rules by fuzzy calculation, and the membership function of the evaporation is calculated. The center of gravity of the inference result obtained by combining Obtain the value as the evaporation index, then The value of the membership function of the evaporation index and the burn-up index in the furnace is inferred by showing the membership function of the feed pusher period for all fuzzy rules by fuzzy calculation, and the membership function of the feed pusher period is calculated. The center of gravity of the inference result obtained by synthesis is obtained by the center of gravity method, and the value of this center of gravity is used as the amount of correction for the pusher period. And add the feed pusher cycle correction amount and the feed pusher cycle reference value together. A combustion control method and apparatus for controlling combustion by adjusting the amount of dust supplied to the grate furnace body.
[0013]
When the position of the center of gravity of the flame is measured, the rotational grate furnace rotational speed correction amount is obtained from the circumferential burning index and the longitudinal burning index at that position, and the burning index is obtained from the fuzzy rules at this time. In addition, since the evaporation amount index is obtained from the waste calorie and the supplied amount, the correction amount of the supplied pusher period is obtained by fuzzy calculation from the evaporated amount index and the burning method index. The rotational speed of the rotary grate furnace is adjusted at the same time as the amount of dust supplied to the main body is adjusted, and combustion control can be automatically performed.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0016]
FIG. 1 shows an embodiment of the present invention. In the rotary grate furnace having the same configuration as the rotary grate furnace shown in FIG. An ITV camera 17 that captures an image from the downstream side to the upstream side is installed, an image processing device 18 that processes an image signal of the combustion state of the dust in the grate furnace body 1 captured by the camera 17 is installed, The highest brightness of the flame 16 processed by the image processing device 18 is regarded as the barycentric point 16b, and the circumferential burning index a and the longitudinal burning index b at the position of the barycentric point 16b of the flame 16 are processed data 20 Fuzzy reasoning that inputs the waste calorie (Kcal / kg) and the amount of feed (kg / h) as process data and stabilizes the position of the center of gravity 16b of the flame 16 within a certain range. Control performance A device 19 is provided, and the fuzzy control arithmetic device 19 issues a rotational grate furnace rotation speed correction command to the motor 8 and at the same time a pusher cycle correction command is issued to the pusher device 12 to supply the grate furnace body 1 Allow the amount to be adjusted.
[0017]
In FIG. 1, the same components as those in FIG. 25 are denoted by the same reference numerals.
[0018]
The image processing device 18 regards the point where the brightness of the flame 16 is the highest as the center of gravity point 16 b, and determines the center of gravity point 16 b of the flame in the longitudinal direction and the circumferential direction from the area of the flame 16 and the center of the grate furnace body 1. It is obtained from the coordinates, and the position detection at the circumferential coordinate and the position detection at the longitudinal coordinate of the gravity center point 16b are performed to measure the circumferential burning index a and the longitudinal burning index b.
[0019]
In addition, as shown in the block diagram of FIG. 2, the fuzzy control arithmetic unit 19 is provided with the circumferential direction and longitudinal direction burning direction indicators a and b measured by the image processing unit 18 and the barycentric point 16b. 9 items for each detected value of the addition point 21 for obtaining the deviation between the reference value (burning index setting value) as a range in the circumferential direction and the longitudinal direction for calming the flame, and the position of the center of gravity 16b of the flame 16 A fuzzy rule unit 23 for performing fuzzy calculation according to fuzzy rules, and a center of gravity of an inference result obtained by synthesizing the rotational grate furnace rotational speed calculated by the fuzzy rule unit 23 to obtain a rotational speed correction amount. A first fuzzy computing unit 22 that infers the rotational speed of the rotary grate furnace, and the rotational correction amount and rotational speed of the rotary grate furnace obtained by the first fuzzy computing unit 22. An addition point 26 for adding the grid furnace rotational speed set value 25, a rotational grate furnace rotational speed controller 27, and a control target (rotary grate furnace) 28, which are obtained by the first fuzzy computing unit 22 The rotational correction amount of the rotary grate furnace and the rotational speed setting value 25 of the rotary grate furnace are added together, and a control command is sent as control information to the motor 8 of the controlled object 28 via the controller 27, so that the rotary grate furnace At the same time, the burn-up index d of overburning or overburning obtained from the control result by the fuzzy rule when the rotation speed correction amount of the rotary grate furnace is obtained is taken out A burning method fuzzy rule part 29 is provided.
[0020]
The fuzzy control arithmetic unit 19 takes in the waste calorie value (Kcal / kg) e and the feed amount (kg / h) f as the process data 20, and first, the waste calorie e and the waste calorie set value and 9 items for each of the addition points 30 for obtaining the deviation, the addition points 31 for obtaining the deviation between the feed amount f and the feed amount set value, and for each of the obtained waste calorie values and the obtained feed amount. The fuzzy rule unit 33 for performing fuzzy calculation with a wide range of fuzzy rules and the center of gravity of the inference result obtained by synthesizing the evaporation amount calculated by the fuzzy rule unit 33 are obtained, and the evaporation amount correction amount (index) (whether the evaporation amount is to be increased) The second fuzzy calculation comprising the fuzzy synthesis unit 34 for obtaining h), i.e., an indicator of whether or not the evaporation amount of the dust contained in the furnace is sufficient. 32 and further burns for each fuzzy rule based on the evaporation amount index h obtained by the second fuzzy computing unit 32 and the longitudinal and circumferential burning method indexes a and b from the burning method fuzzy rule unit 29. A fuzzy rule unit 36 for performing fuzzy calculation by fuzzy rules over nine items from the direction index d, and the center of gravity of the inference result obtained by synthesizing the pusher period for feeding supplied by the fuzzy rule unit 36, A third fuzzy calculator 35 comprising a fuzzy synthesizer 37 for determining the period correction amount, and a supply pusher period correction amount and a supply pusher period reference value 38 determined by the third fuzzy calculator 35. An addition point 39 to be added and a dust supply controller 40 are provided, and control information input to the controller 40 is sent to the pusher device 12 As a control command, the amount of supply is adjusted in accordance with the amount of steam so that the combustion state can be changed.
[0021]
The relationship between the circumferential burn-up index a and the longitudinal burn-up index b based on the flame center of gravity position incorporated in the fuzzy rule unit 23 of the first fuzzy calculation unit 22 and the rotational speed c of the rotary grate furnace associated therewith is as follows. The 9-item fuzzy rule shown is as follows. (1) If a is large (PB) and b is large (PB), c is the current status (NN)
(2) If a is large (PB) and b is medium (NN), c is lowered (NB)
(3) If a is large (PB) and b is small (NB), c is lowered (NB)
(4) If a is medium (NN) and b is large (PB), c is increased (PB)
(5) If a is medium (NN) and b is medium (NN), c is the current status (NN)
(6) If a is medium (NN) and b is small (NB), c is lowered (NB)
(7) If a is small (NB) and b is large (PB), c is increased (PB)
(8) If a is small (NB) and b is medium (NN), c is increased (PB)
(9) If a is small (NB) and b is small (NB), c is the current status (NN)
When the fuzzy rules (1) to (9) are replaced with the fuzzy rule table, the matrix table shown in FIG. 3 is obtained, and the result of the rotational grate furnace rotational speed is as shown in FIG.
[0022]
In the rule part 23, all the fuzzy rules of the above nine items are calculated finely for every deviation between the measured value of the position of the center of gravity 16b of the flame 16 and the reference value, and fuzzy calculation is performed. The fuzzy synthesizing unit 24 performs processing such that the value of the membership function and the value of the membership function of the longitudinal direction index b are indicated in the membership function of the rotary grate furnace rotational speed c by the max-min method. Then, the inference result of the membership function of the rotary grate furnace rotational speed c indicated by the rule unit 23 is obtained by the center of gravity method as an actual rotational speed correction amount.
[0023]
Now, as shown in FIG. 4, the gravity center point 16b of the flame 16 is an X position (a = 0.15m, b = 2.25m) as an example from the X position (a = 0.0m, b = 2.0m). As shown in FIG. 4, when the position of the center of gravity 16b is moved from the X position to the γ position as shown in FIG. 4, it corresponds to the above-mentioned fuzzy rule (2) and it is said that it is not burned. Therefore, control is performed to lower the rotational speed of the rotary grate furnace. In this case, the following operation is performed.
[0024]
First, the membership function of the burning index a is as shown in FIG. 5 (a), the membership function of the burning index b is as shown in FIG. 5 (b), and the rotation of the rotary grate furnace The membership function of the number c is as shown in FIG.
[0025]
In each membership function shown in FIGS. 5 (a) and 5 (b), large, medium and small ranges are determined based on the intersections A and B. In the burning index a in FIG. > 0.1 for large, -0.1 ≦ a ≦ 0.1 for medium, a <−0.1 for small, and b> 2.25 for the burning index b in FIG. Large, 1.75 ≦ b ≦ 2.25, medium, and b <1.75, small.
[0026]
In FIG. 4, when the position of the center of gravity 16b of the flame 16 is moved from X to γ, the positions of γ are a = 0.15 and b = 2.25. Since 0.15 exceeds the numerical value 0.1, it is set as large (PB), and b is in the range of 1.75 ≦ b ≦ 2.25 in FIG. , Medium (NN), and this is calculated in detail with the membership function for nine items from fuzzy rules (1) to (9) based on the rules of FIG.
[0027]
FIG. 6 shows the membership function values calculated for the fuzzy rules (1) to (9) above, and FIG. 6 (a) shows the membership function values according to the fuzzy rule (1) at the position of γ. 6 (b) also shows the values of membership functions according to fuzzy rule (2). Similarly, FIG. 6 (c) (d) (d) (e) (e) (f) (g) The membership function values according to fuzzy rules (3), (4), (5), (6), (7), (8), and (9) are shown.
[0028]
In the fuzzy rule (1), since a is large and b is large, the value of the membership function of a is 0.7 at a = 0.15, and the value of the membership function of b is b Although 0.5 at the point of 2.25, 0.5 is applied by applying the min method. When this is shown in the membership function of the rotational speed c of the rotary grate furnace, it becomes a value as shown in the figure.
[0029]
Similarly, in the fuzzy rule (2), since a is large and b is medium, the value of the membership function of a is 0.7, the value of the membership function of b is 0.5, and the min method A smaller value of 0.5 is taken for this and is shown in the membership function of the rotational speed c of the rotary grate furnace.
[0030]
In this way, with respect to the measured flame center-of-gravity point position γ, the value of the membership function of a and the value of the membership function of b are small by applying the min method over all of the fuzzy rules (1) to (9). This value is shown in the membership function of the rotational speed c of the rotary grate furnace, and the result shown in the membership function of the rotational speed c of the rotary grate furnace in FIGS. Then, the inference result is expressed as a graphic as shown in FIG. 7 by the fuzzy synthesis unit 23, the barycentric position x of the graphic is obtained by the barycentric method, and the value of that point is taken out as the rotation speed adjustment amount.
[0031]
FIG. 7 shows the rotational speed c of the rotary grate furnace by applying the min method to all of the fuzzy rules {circle around (1)} to {circle around (9)} when the flame center of gravity moves from X to γ as shown in FIG. The position of γ corresponds to the range shown in (2) of fuzzy rules (1) to (9), and the fuzzy rule (2) is shown. , The rotational speed c of the rotary grate furnace is selected as NB in FIG. 3 showing the result of the rotational speed c, and the rotational speed is “decreased”, and the center of gravity of the figure of FIG. Is obtained by the centroid method, and the value 0.032 rpm of the centroid position x is obtained as the rotation speed (adjustment amount) to be corrected.
[0032]
When the position of the flame center of gravity 16b moves from X to a position different from γ shown in FIG. 4, the fuzzy rules a and b of all the fuzzy rules {circle around (1)} to {circle around (9)} are set in the same manner as described above. The result corresponding to FIG. 7 is obtained by calculating by each membership function, applying the min method, indicating the membership function of the rotational g of the rotating grate furnace c, and obtaining the centroid of the inference result by the centroid method. The adjustment value of the rotational speed c of the rotary grate furnace is obtained based on the fuzzy rule to which the obtained and moved position is applied.
[0033]
In this way, the value obtained by the fuzzy computing unit 22 is output as the rotational speed adjustment amount of the rotary grate furnace, and the rotational speed set value 25 of the rotary grate furnace is added at the addition point 26 as control information. The rotation grate furnace rotation controller 26 inputs the control command to the motor 8 of the controlled object 28 to control the rotation speed of the grate furnace body. In the present invention, the fuzzy calculation is performed. When the rotational speed correction amount of the rotary grate furnace is determined by the unit 22, the combustion method index d, which indicates whether the combustion state in the furnace is in an overburning state or in an overburning state, is displayed in the burning method fuzzy rule unit 29. The matrix table of 3 is used. That is, when the flame center-of-gravity point position 16b is at the position γ, it corresponds to (2) of the fuzzy rules (1) to (9) as described above from FIGS. In the matrix table of FIG. 3, the rotational speed of the rotary grate furnace is set to be lowered (NB), and a combustion index d indicating that the combustion state in the furnace is on the overburning side from the optimum state is obtained.
[0034]
Next, nine items of fuzzy rules indicating the relationship between the waste calorie value e, the amount of feed f, and the amount of evaporation h associated therewith incorporated in the fuzzy rule unit 33 of the second fuzzy operation unit 32 are as follows. It is.
(1a) If e is large (PB) and f is large (PB), lower g (NB)
(2a) If e is large (PB) and f is medium (NN), decrease g (NB)
(3a) If e is large (PB) and f is small (NB), keep g unchanged (NN)
(4a) If e is medium (NN) and f is large (PB), lower g (NB)
(5a) If e is medium (NN) and f is medium (NN), keep g as it is (NN)
(6a) If e is medium (NN) and f is small (NB), increase g (PB)
(7a) If e is small (NB) and f is large (PB), keep g unchanged (NN)
(8a) If e is small (NB) and f is medium (NN), increase g (PB)
(9a) If e is small (NB) and f is small (NB), increase g (PB)
When the fuzzy rules (1a) to (9a) are replaced with the fuzzy rule table, the matrix table in FIG. 8 is obtained, and the evaporation amount results as shown in FIG.
[0035]
The fuzzy rule unit 33 of the second fuzzy computing unit 32 details the fuzzy rules of the above nine items for each deviation between the waste calorie e and the waste calorie set value and for each deviation between the feed amount f and the feed amount set value. A process in which the fuzzy calculation is performed and the membership function value of the waste calorie e and the membership function value of the feed amount f are respectively shown in the membership function of the evaporation amount g by the max-min method. The fuzzy synthesis unit 34 synthesizes the membership function of the evaporation amount g, obtains the center of gravity by the center of gravity method, and sets the value as the evaporation amount index h.
[0036]
As shown in FIG. 9, it is assumed that the waste calorie e is 2150 Kcal / kg with respect to the reference value of 2100 Kcal / kg, and as shown in FIG. On the other hand, when it is 3900 kg / h, the membership function of the waste calorie e is as shown in FIG. 11 (a), and the membership function of the feed amount f is as shown in FIG. 11 (b). The membership function of the evaporation amount g is as shown in FIG.
[0037]
In each membership function shown in FIGS. 11A and 11B, the ranges of large (PB), medium (NN), and small (NB) are determined based on the intersections A and B, and FIG. ) Waste calories e, e> 2175 is large, 2025 ≦ e ≦ 2175 is medium, and e <2025 is small, and in FIG. 11 (b), f> 4060 is large, 3960 ≦ Assuming that f ≦ 4060 is medium and f <3960 is small, when the waste calorie e is 2150 Kcal / kg as described above and the amount of feed f is 3900 Kcal / h, e is as shown in FIG. ) Medium (NN) and f is small (NB), so it corresponds to (6a) of the fuzzy rule, and the control is to increase the evaporation amount, but in the actual operation, the waste calorie e is medium ( NN), and the amount of feed f is small (NB), which is based on the rules of FIG. 8 and the fuzzy rules (1a) to (9a) It will be so finely calculated by the membership function.
[0038]
FIG. 12 shows the values of membership functions calculated for the fuzzy rules (1a) to (9a) when e and f are the above values. FIG. 12 (a) shows the fuzzy rules (1a). In the same way, the values of the membership function are shown in Fig. 12 (b), (c), (d), (e), (f), (f), (t), (c), and (f). (5a) (6a) (7a) (8a) (9a) The membership function values are shown.
[0039]
In the fuzzy rule (1a), since e is large and f is large, the value of the membership function of e is 0.3 at e = 2150, and the value of the membership function of f is f = 3900. However, it is 0 by applying the min method.
[0040]
In the fuzzy rule (2a), since e is large and f is medium, the membership function value of e is 0.3 at e = 2150, and the membership function value of f is f = 3900. However, it is 0 by applying the min method.
[0041]
On the other hand, in the fuzzy rule (3a), since e is large and f is small, the membership function value of e is 0.3 at e = 2150 as in the above, and the membership function of f is The value is 0.7 at f = 3900, but when the min method is applied to take 0.3 and this is shown in the membership function of the evaporation amount g, the value is as shown in FIG. .
[0042]
Similarly, for the fuzzy rules (4a) to (9a), the value of the membership function of e and the value of the membership function of f are applied to the membership function of the evaporation amount g by applying the min method. However, in the fuzzy rule (6a), since e is medium and f is small, the value of the membership function of e is 0.7 at e = 2150, and the value of the membership function of f is f = 3900 is 0.7, and both are 0.7. Therefore, when 0.7 is taken and this is shown in the membership function of the evaporation amount g, the value is as shown in FIG.
[0043]
In this way, the result inferred by the fuzzy synthesizer 34 from the result shown in the membership function of the evaporation amount g in FIGS. 12 (a) to 12 (i) is represented as a figure as shown in FIG. The centroid position y of the figure is obtained by the centroid method, and the value at that point is taken out as an evaporation amount correction amount (evaporation amount index) h.
[0044]
When the waste calorie e and the feed amount f fluctuate, the fluctuating values are calculated by the respective membership functions of the waste calorie e and the feed amount f for all of the fuzzy rules (1a) to (9a) as described above. The min method is applied to indicate the membership function of the evaporation amount g, the center of gravity position of the figure of the inference result is obtained by the center of gravity method, and the value of that point is obtained as the correction amount.
[0045]
When the evaporation amount index h is extracted from the second fuzzy operation unit 32 as described above, the combustion method index obtained by conversion from the rotational speed correction amount of the rotary grate furnace extracted from the first fuzzy operation unit 22 The fuzzy calculation unit 35 obtains the amount of correction of the pusher period from d and h.
[0046]
In this case, nine items indicating the relationship between the evaporation amount index h and the combustion method index d incorporated in the fuzzy rule unit 36 of the third fuzzy calculation unit 35 and the accompanying fuel supply pusher cycle (sec / cyc) i. The fuzzy rules are as follows:
(1b) If h is large (PB) and d is large (PB), i is shortened (increase the amount of waste input) (2b) If h is large (PB) and d is medium (NN) I should be shorter
(3b) If h is large (PB) and d is small (NB), i remains unchanged
(4b) If h is medium (NN) and d is large (PB), i remains unchanged
(5b) If h is medium (NN) and d is medium (NN), i remains the same
(6b) If h is medium (NN) and d is small (NB), i is lengthened (the amount of waste input is reduced).
(7b) If h is small (NB) and d is large (PB), i is lengthened.
(8b) If h is small (NB) and d is medium (NN), i is lengthened
(9b) If h is small (NB) and d is small (NB), i is lengthened.
When the fuzzy rules (1b) to (9b) are replaced with the fuzzy rule table, the matrix table shown in FIG. 14 is obtained, and the result of the feed pusher cycle is shown in FIG.
[0047]
Similar to the fuzzy rule units 23 and 33 of the first and second fuzzy calculation units 22 and 32, the fuzzy rule unit 36 performs fine calculation and performs fuzzy calculation for all the fuzzy rules of the above nine items, and the evaporation amount index. The value of the membership function of h and the value of the membership function of the burning index d are indicated in the membership function of each feed pusher period i by the max-min method, and the fuzzy rule unit 37 The inference result of the membership function of the duster pusher period i shown at 33 is obtained by the center of gravity method as the actual duster pusher period correction amount.
[0048]
Now, assuming that the evaporation index h is +0.7 and the burning index d is -0.4, the membership function of the evaporation index h is as shown in FIG. The ship function is as shown in FIG. 15 (b), and the membership function of the feed pusher period i is as shown in FIG. 15 (c). Also in the membership function shown in FIGS. 15 (a) and 15 (b), the large, medium, and small ranges are determined based on the intersections A and B. With the evaporation amount index h in FIG. It is determined that 0.4 is large, −0.4 ≦ h ≦ 0.4, medium, h <−0.4, small, and the burning index d in FIG. 15B is large when d> 0.35. , −0.35 ≦ d ≦ 0.35, medium, and d <−0.35, small.
[0049]
In FIG. 15 (a), h is 0.7 (greater than PB) since 0.7 exceeds the numerical value 0.4, d is -0.4 and smaller than the numerical value -0.35, so small (NB), This is calculated in detail with the membership function for the nine items from the fuzzy rules (1b) to (9b) described above.
[0050]
FIG. 16 shows the membership function values calculated for the nine fuzzy rules (1b) to (9b) described above. FIG. 16 (a) shows the membership function values according to the fuzzy rules (1b). FIG. 16 (b) shows the value of the membership function according to the fuzzy rule (2b). Similarly, FIG. 16 (c) (d) (d) (e) (e) (f) (g) (f) The values of membership function according to rules (3b) (4b) (5b) (6b) (7b) (8b) (9b) are shown. In fuzzy rule (2b), the evaporation index h is large and the burning index Since d is medium, the membership function value of h is 0.6 at h = 0.7, but the membership function value of d is 0.2 at d = −0.4. Therefore, 0.2 is applied by applying the min method, and this is shown in the membership function of the feed pusher period i as shown in FIG. So as to such value shown. Similarly, for each fuzzy rule, the value of the membership function of h and the value of the membership function of d are applied to the membership function of the pusher period i by taking the smaller value by applying the min method. The results inferred by the fuzzy synthesizer 37 from the results shown in the membership function of the fuel supply pusher period i in FIGS. 16 (a) to 16 (i) are represented as a figure as shown in FIG. The center of gravity position z of the figure is obtained by the method, the value at that point is taken out as a feed pusher cycle correction amount, and after the feed pusher cycle reference value 39 is added at the addition point 38, the rotary grate is supplied from the dust feed controller 40. It is sent as a control command to the pusher device 12 of the furnace, and the amount of waste input is adjusted. Incidentally, in the case of FIG. 17, the center of gravity position z is located in the center, and if the value of 400 sec / cyc is positioned as a good value, it matches this, so the current state is maintained.
[0051]
When the value of the evaporation index h or the value of the burning index d changes, the values of the fuzzy rules (1b) to (9b) are calculated with the membership functions of h and d in the same manner as described above. This is shown in the membership function of the dusting pusher period i, and the center of gravity of the figure created by synthesizing it is obtained by the center of gravity method.
[0052]
When the correction amount of the dusting pusher period obtained as described above is output from the fuzzy calculation unit 35, the dusting pusher period reference value is added at the addition point 39 and is input to the dust supply controller 40 as control information. From here, a control command is sent to the pusher device 12 of the controlled object 28, and the dust supply amount is automatically controlled, and the combustion state of the dust 11 in the grate furnace body 1 is changed.
[0053]
Next, FIG. 18 shows another embodiment of the present invention. From the fuzzy rule when the rotational speed correction amount of the rotary grate furnace is obtained in the same configuration as the block diagram shown in FIG. The burning method fuzzy rule unit 29 for obtaining the burning method index is a burning method fuzzy rule unit 41 that subdivides the fuzzy rules by the burning method indexes a and b, and the other configuration is shown in FIG. The same components are denoted by the same reference numerals.
[0054]
In the burning method fuzzy rule unit 41, nine items of fuzzy rules indicating the relationship between the circumferential burning index a and the longitudinal burning index b shown in FIG. 3 and the rotational speed c of the rotary grate furnace associated therewith are shown. In the matrix table, NB is subdivided into two stages, NS (slightly small) and NB (small), and PB is subdivided into two stages, PS (slightly large) and PB (large). As shown in FIG. 3, it is divided into three equal parts to five equal parts, and the membership function is divided into five parts as shown in FIG. 20, and the ranges of large, slightly large, medium, slightly small and small are determined.
[0055]
The evaporation amount index h is also divided into 5 parts corresponding to the 5 way divided combustion method index d obtained from the combustion method fuzzy rule unit 41, and the combustion method index d, the evaporation amount index h, and the accompanying supply. FIG. 21 shows fuzzy rules indicating the relationship of the dust pusher period i in a matrix table.
[0056]
Assuming that the evaporation index h is +0.7 and the combustion index d is −0.4, the fuzzy rules of the following four items are used to obtain the dusting pusher period i.
(1c) If h is large (PB) and d is a little small (NS), i is a little short
(2c) If h is large (PB) and d is small (NB), i remains unchanged
(3c) If h is a little large (PS) and d is a little small (NS), i remains the same
(4c) If h is a little large (PS) and d is small (NB), i will be a little longer
The results of the feed pusher period i according to the fuzzy rules (1c) to (4c) are as shown in the matrix table of FIG.
[0057]
As described above, the membership function of the evaporation index h when the evaporation index h is +0.7 and the burning index d is −0.4 is as shown in FIG. The membership function of the direction index d is as shown in FIG. 22 (b), and the membership function of the feed pusher period i is as shown in FIG. 22 (c).
[0058]
FIG. 23 shows the values of membership functions calculated for the fuzzy rules (1c) to (4c) above. FIG. 23 (a) shows the values of membership functions based on the fuzzy rules (1c). (B) is the membership function value according to fuzzy rule (2c), FIG. 23 (c) is the membership function value according to fuzzy rule (3c), and FIG. 23 (d) is the member according to fuzzy rule (4c). The values of the ship function are shown respectively. For all of the fuzzy rules (1c), (2c), (3c), and (4c), the value of the membership function of the evaporation index h and the value of the membership function of the burning index d Is applied to the membership function of the duster pusher period i by applying the min method, and the result is similar to the membership function of the duster pusher period shown in FIGS. 23 (a), (b), (c) and (d). Next The result is synthesized by the fuzzy synthesis unit 37 and inferred, and the inference result is represented as a figure as shown in FIG. 24. The centroid position z 'of the figure is obtained by the centroid method, and the value of the point is -2%. As a correction amount for the dusting pusher period. This is sent as a control command from the dust supply controller 40 to the pusher device 12 of the rotary grate furnace in the same manner as described above to adjust the amount of dust input, but the correction amount is -2% in FIG. Therefore, the dusting pusher cycle is slightly shorter than the current situation, and the amount of dust input is slightly increased, and fine control can be performed as compared with the case of the above three divisions.
[0059]
In the above-described embodiment, the case where the fuzzy rules are nine items is shown. However, the number of fuzzy rules is arbitrary, and various changes can be made without departing from the scope of the present invention. It is.
[0060]
【The invention's effect】
As described above, according to the combustion control method and apparatus of the rotary grate furnace of the present invention, the position of the center of gravity of the flame due to the dust combustion in the rotary grate furnace is measured in the circumferential direction and the longitudinal direction of the furnace, and the center of gravity is measured. In order to stabilize the point position within a certain range, for each fuzzy rule stored in advance in the fuzzy rule part of the first fuzzy calculation part, the circumferential burning index and the longitudinal direction index for the flame center of gravity point position are described. Calculating with each membership function of burning index and showing it in the membership function of the rotational grate furnace rotation speed for each fuzzy rule, synthesizing it with the fuzzy composition part and finding the center of gravity by the center of gravity method and rotating The amount of rotation correction of the grate furnace is used, and the rotation number of the rotation grate furnace is adjusted. , Rotational speed of rotary grate furnace Obtained from the control result by the fuzzy rule when the correction amount is obtained The combustion index in the furnace is obtained from the matrix table of fuzzy rules, while the waste calorie and the amount of feed are calculated by membership function for each fuzzy rule of the fuzzy rule part of the second fuzzy calculation part, and the membership of evaporation amount This is shown in the function, and this is synthesized by the fuzzy synthesis unit, the center of gravity is obtained by the center of gravity method, the index for whether the evaporation amount should be increased or decreased, the evaporation amount index and the rotational speed of the rotary grate furnace are obtained The burn-up index in the furnace when trying to adjust the fuzzy rule is calculated with the membership function for each fuzzy rule in the fuzzy rule part of the third fuzzy calculation part, and shown in the membership function of the dusting pusher period. The fuzzy synthesis unit synthesizes the center of gravity by the center of gravity method to determine the amount of correction of the pusher period, and controls the rotary grate furnace pusher device to control the amount of waste input. Therefore, the rotational speed of the rotary grate furnace is adjusted so that the measured flame center-of-gravity position is stabilized within a certain range by measuring the center-of-gravity position of the flame from the circumferential direction and the longitudinal direction. At the same time, the amount of feed is automatically adjusted based on the evaporation index obtained from the waste calorie and the amount of feed at that time, and the combustion index in the furnace, and the combustion status in the furnace is accurately adjusted. In addition, by using a fuzzy rule in which the evaporation amount index and the burning index are multi-divided, it is possible to achieve excellent effects such as higher accuracy control.
[Brief description of the drawings]
FIG. 1 shows an embodiment of a combustion control method and apparatus for a rotary grate furnace according to the present invention. FIG. 1 (a) is a schematic diagram, and FIG. FIG.
2 is a block diagram showing a configuration of a fuzzy control arithmetic device in FIG. 1. FIG.
FIG. 3 is a matrix table showing the control result of the rotational grate furnace rotation speed by nine fuzzy rules stored in advance in the fuzzy rule part of the fuzzy operation part in FIG. 2;
FIG. 4 is a schematic diagram showing each value of a circumferential burning index and a longitudinal burning index when the inside of the grate furnace main body is viewed in a plan view, and a case where the flame center of gravity shifts from the X position to the γ position. It is.
FIG. 5 shows the membership functions of the circumferential burning index, the longitudinal burning index, and the rotational grate furnace rotation speed. (A) is a criterion for judging large, medium and small with respect to the circumferential burning index. (B) is a diagram showing large, medium, and small judgment criteria for the longitudinal burning index, and (C) is a diagram showing large, medium, and small judgment criteria for the rotational grate furnace rotation speed. .
6 shows the values of the membership functions of the circumferential burning index a and the longitudinal burning index b according to fuzzy rules {circle around (1)} to {9} for the γ position in FIG. The states shown in the membership function of the number c are shown, and (i) to (ri) correspond to the fuzzy rules {circle around (1)} to {circle around (9)}.
7 is a view in which a rotational speed correction amount is obtained by a center of gravity method from an inference result obtained by synthesizing the rotational grate furnace rotational speed shown in FIG. 6;
FIG. 8 is a matrix table of fuzzy rules stored in advance in the fuzzy rule part of the second fuzzy operation part of FIG. 2 in order to obtain the control result of the evaporation amount based on the waste calorie and the supplied amount.
FIG. 9 is a diagram showing garbage calorie values.
FIG. 10 is a diagram illustrating a value of a dust supply amount.
FIG. 11 shows each membership function of waste calorie, supply amount, and evaporation amount. (A) is a diagram showing judgment criteria of large, medium, and small with respect to waste calorie. The figure which shows the judgment criterion of large, medium, and small, (c) is a figure which shows the judgment standard of large, medium, and small with respect to the evaporation amount.
FIG. 12 shows the values of the waste calorie and supply amount membership functions according to fuzzy rules (1a) to (9a), and the state in which these values are shown in the evaporation amount membership functions for FIGS. (I) to (ri) are diagrams corresponding to the fuzzy rules (1a) to (9a).
13 is a diagram in which an evaporation amount index is obtained by a centroid method from an inference result obtained by combining the evaporation amounts shown in FIG.
14 is a matrix table of fuzzy rules stored in advance in the third fuzzy operation unit of FIG. 2 in order to obtain a control result of the dusting pusher cycle based on the evaporation amount index and the burning method index.
FIG. 15 shows the membership function of the evaporation index, the burning index, and the feed pusher cycle. (A) is a diagram showing judgment criteria of large, medium and small with respect to the evaporation index, and (b) is burning. The figure which shows the big, medium, and small judgment criteria with respect to a direction index, (c) is a figure which shows the big, middle, and small judgment criteria with respect to a feed pusher period.
FIG. 16 shows the membership function values of the evaporation index and the combustion index according to fuzzy rules (1b) to (9b) when the evaporation index is +0.7 and the burning index is -0.4. The values are shown in the membership function of the feed pusher period, and (i) to (ri) correspond to the fuzzy rules (1b) to (9b).
FIG. 17 is a diagram in which the amount of correction of the feed-pusher cycle is obtained by the center of gravity method from the inference result obtained by synthesizing the feed-pusher cycle shown in FIG.
FIG. 18 is a block diagram showing another embodiment of the present invention.
FIG. 19 is a matrix table in which PB is divided into two stages of PS and PB and NB is divided into two stages of NS and NB in the matrix table of fuzzy rules (1) to (9).
FIG. 20 is a diagram showing a state where the membership function is divided into five based on FIG.
FIG. 21 is a matrix table showing a control result of a dusting pusher period by dividing an evaporation amount index and a burning index into five.
FIG. 22 shows each membership function of an evaporation amount index, a combustion method index, and a feed pusher period divided into five parts. (A) is a judgment of large, slightly large, medium, slightly small, and small with respect to the evaporation amount index. Figure showing the criteria, (b) is a diagram showing the judgment criteria of large, slightly large, medium, slightly small and small for the burning method index, (c) is large, slightly large, medium, slightly small for the feed pusher cycle, It is a figure which shows a small criterion.
FIG. 23 shows the values of the membership function of the evaporation index and the burning index according to fuzzy rules (1c) to (4c) when the evaporation index is +0.7 and the burning index is −0.4. (B) (b) (c) (d) corresponds to fuzzy rules (1c) (2c) (3c) (4c) It is a figure to do.
FIG. 24 is a diagram in which the amount of correction for the feed-pusher cycle is obtained by the center-of-gravity method from the inference result obtained by synthesizing the feed-pusher cycle shown in FIG.
FIG. 25 is a schematic view showing an example of a rotary grate furnace.
FIG. 26 is a diagram for performing a burnout point measurement of a flame generation point in a conventional grate furnace body.
FIG. 27 is a diagram showing a flame generation location when a dust layer changes in a conventional grate furnace main body.
[Explanation of symbols]
1 Grate furnace body
8 Motor
11 Garbage
12 Pusher device
16 flame
16b Center of gravity
17 ITV TV
18 Image processing device
19 Fuzzy control arithmetic unit
20 Process data
21 Additional points
22 1st fuzzy operation part
23 Fuzzy rule part
24 Fuzzy synthesis unit
26 Additional points
27 Rotary controller for rotary grate furnace
28 Control target
29 How to Burn Fuzzy Rules
30 Additional points
31 Additional points
32 Second Fuzzy Operation Unit
33 Fuzzy rule part
34 Fuzzy synthesis unit
35 Third Fuzzy Operation Unit
36 Fuzzy rule part
37 Fuzzy composition unit
39 Adding part
40 Dust supply controller
41 How to burn fuzzy rules
a Circumferential Burning Index
b Longitudinal burning index
c Rotary grate furnace rotation speed
d Burning index
e Garbage Calories
f Dust supply amount
g Evaporation
h Evaporation amount index

Claims (6)

The position of the center of gravity of the flame when the garbage supplied into the rotary grate furnace is burned while rotating the grate furnace body is measured from the circumferential direction and the longitudinal direction of the grate furnace body, and the position of the center of gravity point Is a stable combustion within a certain range, the values of the membership functions of the circumferential burn direction index and the longitudinal burn direction index are calculated by fuzzy calculation for all fuzzy rules. The center of gravity of the inference result obtained by synthesizing the membership function of the rotary grate furnace rotational speed is obtained by the center of gravity method, and the value of this center of gravity is obtained as the rotational speed correction amount of the rotary grate furnace. And adjusting the rotational speed of the rotary grate furnace by adding the rotational speed correction amount of the rotary grate furnace and the rotational speed setting value of the rotary grate furnace, and at the same time, the rotational grate furnace for each flame center-of-gravity point position. Rotational speed correction amount is Seeking burning how indication of control results or al furnace by Fuzzy rules for was because, then, the membership function of all the fuzzy rules the value of each membership function refuse calories a paper dust quantity by fuzzy computation evaporation The center of gravity of the inference result obtained by synthesizing the membership function of the evaporation amount is obtained by the center of gravity method, and the value of this center of gravity is obtained as the evaporation amount index. It is obtained by inferring the membership function value of the burn-up indicator in the furnace by showing the membership function of the feed pusher period for all fuzzy rules by fuzzy calculation, and synthesizing the membership function of the feed pusher period. determined by centroid method the center of gravity of the inference result, the value of center of gravity obtained as paper dust pusher cycle correction amount, and the fed-dust pusher cycle correction amount Combustion control method for rotating grate furnace and performing combined addition of the dust pusher cycle reference value by adjusting the feed dust amount of the grate furnace body combustion control. The fuzzy rules are divided into three parts: large, medium, and small for the circumferential burn index and longitudinal burn index, the waste calorie and feed rate, the evaporation index and the burn index in the furnace for each flame center of gravity. The combustion control method for a rotary grate furnace according to claim 1, wherein nine items are made, fuzzy calculation is performed for all of the fuzzy rules of each of the nine items, and the rotational grate furnace rotation speed, the evaporation amount, and the feed pusher period are inferred. . Circumferential direction and the longitudinal direction of the rotating grate furnace grate furnace dust image signal processing to the grate furnace body the center of gravity position of the flame of the combustion conditions in the grate furnace body that captures the body with a camera for imaging An image processing device for measuring a circumferential burning index and a longitudinal burning index determined from the coordinates from the above, and each circumferential and longitudinal burning index measured by the image processing device and these a first fuzzy computation unit to determine a rotational speed correction amount of the rotation grate furnace and a calculation of the membership function for fuzzy rule all for each deviation between the reference value, the rotational grate in the first fuzzy computation unit and burning how fuzzy rule section to make out taking the burning way indication in the resulting furnace from the control result by the fuzzy rule when the rotation speed correction amount of the furnace is obtained, the fuzzy rules for each value of the waste calories a paper dust amount A second fuzzy computation unit to seek evaporation amount index by performing the calculation of membership functions for all the circumferential direction and from the evaporation index and said burning how fuzzy rule area obtained by the second fuzzy computation unit A third fuzzy operation unit that calculates a membership pusher period correction amount by calculating a membership function for all the fuzzy rules from the fuzzy rules for each fuzzy rule based on the longitudinal burning index, and The rotational grate furnace rotational speed correction amount from the first fuzzy arithmetic unit is adjusted with the rotational grate furnace rotational speed correction amount, and at the same time, the feed gland pusher period correction amount from the third fuzzy arithmetic unit is entered into the grate furnace body. A combustion control device for a rotary grate furnace, characterized in that it has a configuration provided with a fuzzy control arithmetic device configured to adjust the amount of dust supply. The first fuzzy operation unit calculates the membership function of the rotational grate furnace speed from the values of the membership function of the circumferential burning index and the membership function of the longitudinal burning index for all the previously stored fuzzy rules. A fuzzy rule unit that performs the processing shown in FIG. 2 and a fuzzy synthesis unit that obtains the center of gravity of the inference result of the membership function of the rotary grate furnace rotational speed indicated by the fuzzy rule part as a rotational speed correction amount. The combustion control device for a rotary grate furnace according to claim 3 , wherein the combustion control device is configured as follows. The second fuzzy computation unit performs fuzzy computation for all the fuzzy rules stored in advance for each waste calorie value and feed amount for which the deviation between the waste calorie set value and the feed amount set value is obtained. The fuzzy rule part for performing the processing shown in the membership function of the evaporation amount from the value of the membership function of the waste calories and the value of the membership function of the feed amount, and the evaporation amount indicated by the fuzzy rule part 4. The combustion control device for a rotary grate furnace according to claim 3 , wherein the combustion control device comprises a fuzzy composition unit that obtains the center of gravity of the inference result of the membership function as an evaporation amount index. The third fuzzy calculation unit is stored in advance from the evaporation index obtained by the second fuzzy calculation unit and the burning index for each fuzzy rule based on the circumferential and longitudinal burning index from the burning fuzzy rule unit. Fuzzy operation is performed for all the fuzzy rules that have been set, and the processing shown in the membership function of the feed pusher cycle from the membership function value of the evaporation index and the membership function value of the burning index is performed. 4. The configuration according to claim 3, comprising a rule part and a fuzzy composition part for obtaining the center of gravity of the inference result of the membership function of the feed pusher period indicated by the fuzzy rule part as a feed pusher period correction amount. Combustion control device for rotary grate furnace.

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