CN115479276A

CN115479276A - Control device, waste incineration facility, control method, and program

Info

Publication number: CN115479276A
Application number: CN202210388412.1A
Authority: CN
Inventors: 广江隆治; 佐濑辽; 森山慧
Original assignee: Mitsubishi Heavy Industries Ltd
Current assignee: Mitsubishi Heavy Industries Ltd
Priority date: 2021-05-31
Filing date: 2022-04-14
Publication date: 2022-12-16
Also published as: JP2022183710A

Abstract

[ problem ] to provide a control device capable of suppressing the variation of combustion in a waste incineration facility. [ solution ] A control device is provided with: a data acquisition unit that acquires a measurement value measured by a sensor provided in the waste incineration facility; a combustion speed estimating unit that estimates a combustion speed in a furnace of the waste incineration facility using the measurement value; and a control unit that controls the amount of garbage supplied or the flow rate of combustion air supplied to the incinerator based on the combustion speed.

Description

Control device, waste incineration facility, control method, and program

Technical Field

The present invention relates to a control device for a waste incineration facility, a control method, and a program.

Background

In the garbage power generation in which a boiler is installed in a garbage incineration facility, heat generated during garbage incineration is recovered, and generated steam is used to generate power, it is economically important to generate additional value as fuel from garbage, rather than simply using garbage as waste. In order to increase the added value of refuse as fuel, it is most effective to stabilize the amount of steam generated and to generate electricity as planned.

In general, an incinerator for incinerating municipal waste, industrial waste, or the like is provided with a hopper, and garbage or the like is lifted by a crane and charged into the hopper, and the garbage in the hopper is sequentially supplied to the incinerator through a chute and a garbage feeding device (recovery facility) disposed at the lower portion thereof. As the garbage feeding device, there are various types, and a pusher type garbage feeding device that pushes garbage toward an incinerator by a reciprocating motion is often used. The pusher is located below the hopper and chute and when extended pushes the refuse around it out towards the incinerator. The pusher has a limited stroke and cannot push the waste further out when fully extended. Therefore, after the pusher is fully extended, it is temporarily retracted and then extended.

There are various forms of feeding waste to an incinerator by a pusher type. For example, patent document 1 discloses a control method for adjusting the amount of garbage supplied to an incinerator per unit time by the number of reciprocating motions of a pusher per unit time. In the control method described in patent document 1, the number of reciprocating operations of the pusher per unit time is increased or decreased in accordance with the change in the moisture content of the waste, thereby suppressing the change in the steam flow rate. The steam flow rate varies according to the amount of heat generated per unit volume of waste supplied. The method of patent document 1 focuses on moisture of garbage which is a cause of fluctuation of a calorific value, but actually changes not only the moisture but also the calorific value. For example, the content of synthetic resin in the garbage affects the amount of heat generation as well as the moisture.

In addition, in the method of patent document 1, a sensor for measuring moisture is required. In the case of the method described in patent document 1, when garbage containing a large amount of water is detected, it is predicted that the supply of garbage to the incinerator causes activation or inactivation of combustion, and feed forward compensation is performed. However, since the time required for detecting moisture until the moisture is actually supplied to the furnace cannot be accurately managed, the feed-forward compensation has an error.

Patent document 2 discloses a waste combustion control method for calculating an estimated heat generation amount per unit waste amount. In the case of the combustion control method of patent document 2, the boiler evaporation amount is calculated from the estimation of the amount of heat generated per unit supply amount of waste. However, as described below, in order to estimate the amount of heat generated per unit supply amount of waste, data of several hours is required, and the estimated value is a value obtained by averaging several hours, and therefore, particularly when the property of waste temporally fluctuates, it is not possible to estimate "the amount of heat generated per unit time of waste" at the current time point in time. Therefore, the estimated boiler evaporation amount used for the garbage transport and the adjustment of the primary combustion air is not accurate, and the variation of the boiler evaporation amount is unavoidable. Further, paragraph 0013 of patent document 3 describes: assuming that the waste is composed of water, combustible components and ash, the ash ratio and the combustible component composition ratio of the waste are fixed, only the lower calorific value of the combustible components is obtained based on the long-term material balance, and the material-heat balance is calculated using an average value of about several minutes to 60 minutes for other required process values, so as to estimate the lower calorific value of the waste. However, it is difficult to estimate the higher calorific value or the lower calorific value in a short time of, for example, about 1 minute. The lower calorific value and the upper calorific value are the calorific values [ J/kg ] per unit mass, and are calculated by the following equation (1) in principle with respect to the supplied garbage. Since the following description is common to the lower calorific value and the upper calorific value, the lower calorific value is unified.

[ number formula 1]

The denominator of equation (1) is at time t ₁ To time t ₂ Mass of waste [ kg ] supplied therebetween]. Numerator represents the time t ₁ To time t ₂ Heat value of garbage supplied in between [ J]. Integral interval of denominator, starting point t ₁ And end point t ₂ The time difference of (a) may be, for example, 1 minute or less. However, the integration interval of the molecule, the starting point t ₁ And end point t ₃ The time difference of (2) does not have to be dealt with as such. For pulverized coal, petroleum, combustible gas, the pair of furnace feeds burn off immediately, so the end point t of the integration interval of the molecules ₃ May be compared with t as the end point of the integration interval of the denominator ₂ Since the amounts are the same, the lower calorific value can be calculated within 1 minute, for example, without delay. If the supply is immediately burnt out, it is not important in the calculation of the numerator to distinguish when the heating of the supplied refuse is achieved, so it is possible to allow an assumption t ₃ ＝t ₂ Simply will time t ₁ To time t ₂ The total heat generation of (2) is a heat generation amount achieved by the garbage supplied at the same timing. However, unlike coal dust and the like, since garbage requires 1 hour or more until it is burned out, t is an end point of the integral of the amount of heat generation ₃ Must be set to the ratio t ₂ At least about 1 hour long. Therefore, in the calculation of the molecule of the formula (1), long-term data of at least the time (for example, about 1 hour) until the molecule is burned out is required. However, it is the lower calorific value of the garbage supplied 1 hour ago that is known by calculation. Even if the lower calorific value of 1 hour ago is known, the real-time control is not so effective.

In practice, the lag is more than 1 hour. This time lag will be explained below. At time t ₁ To time t ₃ The heat generation amount of (a) includes: time t ₁ The calorific value of the waste previously fed and already located inside the furnace; and time t ₂ Since the amount of heat generated by garbage supplied later, the calculation of the numerator of equation (1) is essentialWill only be controlled at time t ₁ And time t ₂ It is difficult to calculate the heat generation by the garbage supplied in between separately from the heat generation of the garbage. Therefore, simply integrating the heat generation amount, the heat generation amount of the denominator is time t ₁ To time t ₃ The total amount of heat generation, and the amount of supply of molecules is not limited to the time t ₁ To t ₂ The lower heating value is too large. For example, when setting t ₁ ＝0、t ₂ =1 minute, assuming that it takes 60 minutes until it is burnt out, t ₃ If the calorific value is simply integrated in 61 minutes, the lower calorific value is about 60 times the actual value. To prevent this, the integral interval of the denominator is set to be several times as long as the time from the garbage to the burnout, and t is set to be ₂ And t ₃ The value of (b) is close to being valid. For example, if t ₁ ＝0、t ₂ =300 min, t ₃ If =360 minutes, the lower calorific value may be 1.2 times the actual value, which may be a good approximation. However, the lower calorific value obtained by this method is further delayed in time, and is obtained by averaging the calorific values over a long period of time, rather than the timely calorific values at that time. In this way, the estimated value of the lower calorific value is basically accompanied by a delay and an averaging of several hours, and does not contribute to the operation when the combustion state rapidly changes.

Documents of the prior art

Patent literature

Patent document 1: japanese patent laid-open publication No. 2019-178850

Patent document 2: japanese patent No. 5996762

Patent document 3: japanese patent No. 3822328

Patent document 4: japanese Kokai publication Sho 63-61621

Disclosure of Invention

Problems to be solved by the invention

Provided is a control method for detecting a fluctuation in combustion of a waste incinerator at an early stage and suppressing the fluctuation.

The present invention provides a control device, a waste incineration apparatus, a control method, and a program that can solve the above-described problems.

Technical scheme

The control device of the present invention includes: a data acquisition unit that acquires a measurement value measured by a sensor provided in the waste incineration facility; a combustion speed estimating unit that estimates a combustion speed in an incinerator of the waste incineration facility using the measurement value; and a control unit that controls the amount of garbage supplied or the flow rate of combustion air supplied to the incinerator based on the combustion speed.

Further, the control method of the present invention includes: a step of acquiring a measurement value measured by a sensor provided in the waste incineration apparatus; estimating a combustion speed in an incinerator of the refuse incineration facility using the measurement value; and controlling the amount of garbage supplied or the flow rate of combustion air supplied to the incinerator based on the combustion speed.

Further, a waste incineration apparatus of the present invention includes: an incinerator for incinerating garbage; a garbage feeding device for supplying garbage to the incinerator; a blower for supplying combustion air to the incinerator; a combustion air valve for controlling the flow rate of the combustion air supplied from the blower to the incinerator; and the control device.

Further, the program of the present invention causes a computer to execute: a step of acquiring a measurement value measured by a sensor provided in the waste incineration facility; estimating a combustion speed in an incinerator of the waste incineration facility using the measurement value; and controlling the amount of garbage supplied or the flow rate of combustion air supplied to the incinerator based on the combustion speed.

Effects of the invention

According to the control device, the waste incineration facility, the control method, and the program, the variation in combustion of the waste incineration facility can be suppressed.

Drawings

Fig. 1 is a diagram showing an example of a waste incineration facility according to each embodiment.

Fig. 2 is a diagram showing an example of a functional configuration of a main part of the control device according to the first embodiment.

Fig. 3 is a diagram showing an example of the operation of the control device according to the first embodiment.

Fig. 4 is a diagram showing an example of a functional configuration of a main part of the control device according to the second embodiment.

Fig. 5 is a diagram showing an example of the operation of the control device according to the second embodiment.

Fig. 6 is a diagram showing an example of a functional configuration of a main part of the control device of the third embodiment.

Fig. 7 is a diagram showing an example of the operation of the control device according to the third embodiment.

Fig. 8 is a diagram showing an example of a functional configuration of a main part of a control device according to the fourth embodiment.

Fig. 9 is a diagram showing an example of a functional configuration of a main part of a control device according to a fifth embodiment.

Fig. 10 is a diagram showing an example of the operation of the control device according to the fifth embodiment.

Fig. 11 is a diagram showing an example of a functional configuration of a main part of a control device according to a sixth embodiment.

Fig. 12 is a diagram showing an example of the operation of the control device according to the sixth embodiment.

Fig. 13 is a diagram showing an example of a hardware configuration of the control device according to each embodiment.

Detailed Description

Hereinafter, a refuse incineration facility according to an embodiment will be described with reference to the drawings. In the following description, the same reference numerals are given to components having the same or similar functions. Moreover, a repetitive description of the configuration may be omitted. "XX or YY" is not limited to either XX or YY, but may include both XX and YY. The same applies to the case where the number of selective elements is three or more. "XX" and "YY" are arbitrary elements (e.g., arbitrary information).

(System constitution)

The waste incineration facility 100 includes: a hopper 1 into which garbage is fed; a chute 2 for guiding the garbage put into the hopper 1 to a lower portion; a pusher 10 for feeding the refuse fed through the chute 2 into the combustion chamber 6; a grate 3 for receiving the garbage supplied from the pusher 10, drying and burning the garbage while transferring the garbage; a combustion chamber 6 for burning garbage; an ash outlet 7 for discharging ash; a blower 4 for supplying air; a plurality of wind boxes 5A to 5E for guiding the air supplied from the blower 4 to each part of the grate 3; a duct 14 for directly supplying the air supplied from the blower 4 to the combustion chamber 6; and a boiler 9.

The pusher 10 is a garbage feeding device, and moves in the direction of arrow α to push out the garbage supplied through the chute 2, thereby supplying the garbage to the grate 3. The fire grate 3 is arranged at the bottom of the chute 2 and the combustion chamber 6 and conveys garbage. The grate 3 includes: a drying zone 3A for evaporating and drying the moisture of the garbage supplied from the pusher 10; a combustion zone 3B located downstream of the drying zone 3A for combusting the dried waste; and a post-combustion zone 3C located downstream of the combustion zone 3B and configured to burn unburned components such as fixed carbon components passing through without combustion to ash. Receives a control signal from the control device 20 to control the operating speed of the grate 3.

The blower 4 is disposed below the grate 3, and supplies air to each part of the grate 3 through air boxes 5A to 5E. Branch pipes respectively connecting the duct 8F and the windboxes 5A to 5E are connected to a duct 8F for guiding the air sent from the blower 4 to the windboxes 5A to 5E, and valves 8A to 8E are provided in the branch pipes, respectively, so that the flow rate of the combustion air supplied to the windboxes 5A to 5E can be adjusted by adjusting the opening degrees of the valves 8A to 8E. Receives a control signal from the control device 20, and controls the air volume of the blower 4 and the opening of the valves 8A to 8E. Sometimes collectively referred to as valves 8A-8E are described as primary combustion air valves.

The combustion chamber 6 is composed of a primary combustion chamber 6A and a secondary combustion chamber 6B above the grate 3, and the boiler 9 is disposed downstream of the combustion chamber 6. The primary combustion chamber 6A is arranged above the fire grate 3, and a secondary combustion chamber 6B is arranged above the primary combustion chamber 6A. The thermally decomposed gas generated from the garbage is combusted in the primary combustion chamber 6A, and the thermally decomposed gas that has combusted the remaining unburned components in the primary combustion chamber 6A is sent to the secondary combustion chamber 6B, and is mixed with the secondary combustion air in the secondary combustion chamber to combust the unburned components. A duct 14 connecting the blower 4 and the secondary combustion chamber 6B is connected to the secondary combustion chamber 6B of the combustion chamber 6, and air can be supplied to the combustion chamber 6 by opening and closing a valve 14A provided in the duct 14. The opening degree of the valve 14A is controlled by a control signal from the control device 20. Valve 14A may be referred to as a secondary combustion air valve. The boiler 9 generates steam by exchanging heat between the exhaust gas sent from the combustion chamber 6 and water circulating in the boiler 9. The steam is supplied to a turbine for power generation, not shown, through a pipe 13. A steam flow sensor 11 for detecting the flow rate of steam is provided in the pipe line 13. The steam flow sensor 11 is connected to the control device 20, and transmits the measurement value measured by the steam flow sensor 11 to the control device 20.

A flue 12 is connected to an exhaust gas outlet of the boiler 9, and the exhaust gas subjected to heat recovery by the boiler 9 passes through the flue 12, passes through an exhaust gas treatment facility, not shown, and is then discharged to the outside.

An oxygen concentration sensor 15 that detects the oxygen concentration of the exhaust gas is provided in the flue 12. The oxygen concentration sensor 15 is connected to the control device 20, and the measurement value measured by the oxygen concentration sensor 15 is transmitted to the control device 20. A temperature sensor 17A for measuring the temperature of the second path is provided in the second path of the boiler, and the flue 12 is provided with: a CO concentration sensor 17B for measuring the CO concentration of the exhaust gas; and a NOx concentration sensor 17C that detects the NOx concentration of the exhaust gas. Each of these sensors 17A to 17C is connected to the control device 20, and the measurement values measured by the sensors 17A to 17C are transmitted to the control device 20. Further, the pipe line 8F is provided with a flow rate sensor 17D for detecting the flow rate of the primary combustion air supplied to the primary combustion chamber 6A through the windboxes 5A to 5E, and the pipe line 14 is provided with a flow rate sensor 17E for detecting the flow rate of the secondary combustion air supplied to the secondary combustion chamber 6B. These sensors 17D to 17E are connected to the control device 20, and the measurement values measured by the flow rate sensors 17D to 17E are transmitted to the control device 20. The combustion chamber 6 is provided with a temperature sensor 16 for measuring the temperature in the combustion chamber 6. The temperature sensor 16 is connected to the control device 20, and the measurement value measured by the temperature sensor 16 is transmitted to the control device 20. These sensors are those provided in a general waste incineration power plant.

The control device 20 includes a data acquisition unit 21, a combustion speed estimation unit 22, a control unit 23, and a storage unit 24.

The data acquisition unit 21 acquires various data such as measurement values measured by the

sensors

11, 15, 16, and 17A to 17D and user instruction values. For example, the data acquisition unit 21 acquires a measurement value of the steam flow rate measured by the steam flow rate sensor 11.

The combustion speed estimating unit 22 calculates a combustion speed of the garbage in the combustion chamber 6 (hereinafter, may be referred to as a furnace). As disclosed in patent document 4, the following causes are contradictory among the causes of the decrease in the heat generation amount of the furnace: (a) A situation where the amount of garbage burned in the furnace is reduced (fuel shortage); and (b) a case where the flame is extinguished due to the supplied garbage (excessive fuel). When the amount of heat generation decreases, the steam flow rate measured by the steam flow rate sensor 11 also decreases, and therefore the decrease in the steam flow rate is also caused by the opposite of (a) and (b). In the conventional combustion control, the continuous garbage supply may cause (b) to compensate for the fuel deficiency in (a), and the amount of heat generation may be decreased (reverse response). Therefore, in the conventional mechanical equipment, when the time for which the heat generation amount is reduced continues for a long period of time to some extent, an alarm is issued, and the cause is estimated by the operator and a recovery operation for removing the cause is performed. In contrast, in the present invention, the combustion speed estimating unit 22 estimates in real time the difficulty of combustion of the garbage in the entire furnace, that is, the combustion per unit time occurring in the furnace, that is, the combustion speed, based on the "already-installed" sensors (the steam flow rate sensor 11, the temperature sensor 16, and the oxygen concentration sensor 15 in this order) such as the steam flow rate, the combustion chamber temperature, and the oxygen concentration in the exhaust gas, and uses the estimated combustion speed for the calculation of the supply amount of the combustion air and the supply amount of the garbage. As will be described later, in the control of the garbage supply amount according to the present invention, the garbage supply amount is determined so as to suppress variation in the steam flow rate by feedback control. At this time, the set value of the feedback controller for commanding the garbage supply amount is adapted to the estimated combustion speed. Specifically, for example, since the case (combustion speed is low) where garbage is difficult to burn corresponds to (b), the feedback gain is reduced to avoid the overfeeding. Otherwise, since (a) corresponds to the case (a), the feedback gain is set to a normal value. This can appropriately cope with the reduction in the respective amounts of heat generation of (a) and (b).

In order to cause the estimation result of the combustion speed to function as intended, it is important to estimate the combustion speed of the refuse as soon as possible. As described with reference to patent documents 2 and 3, the estimation of the amount of heat generation per unit supply amount of garbage (lower-order heat generation amount) has a problem in principle. Therefore, in the present invention, the combustion speed is used as an index instead of the lower heat generation amount. The lower calorific value is the calorific value per unit mass of the supplied refuse, and the combustion rate indicates the heat generation of the entire furnace regardless of the mass of the refuse located in the furnace. Further, the combustion speed is not limited to the combustion of the garbage in the furnace but includes the combustion of the thermal decomposition gas. As described above, in the waste incineration facility 100, since it takes time for waste to be put into combustion, a large amount of waste is accumulated in the furnace. The accumulated combustion rate varies with time, though it is almost a fixed value as a whole, and as a result, the steam flow rate measured by the steam flow rate sensor 11 varies. The reasons for the variation in the combustion speed are various: the newly supplied garbage contains a large amount of water and interferes with the surrounding combustion, and the supply of combustion air is changed due to the breakdown of the garbage layer or the like. The variation in the combustion speed is also expressed in the measured values (the combustion room temperature, the oxygen concentration in the exhaust gas, and the like) of the waste incineration facility 100 in addition to the steam flow rate. In the present invention, the combustion speed in the furnace is estimated in real time from the measurement values obtained by the conventional sensors.

(order of estimating Combustion speed)

In the waste incineration apparatus 100, the combustion speed of the waste constantly fluctuates, which is unavoidable. In the waste incineration facility 100, even if a part of the supplied waste is instantaneously burned, most of the waste is accumulated as combustible on the grate 3 of the furnace and is burned in order from the dried part. For example, suppose there is a block of dried waste, the surface of which is burning. At this time, when the grate 3 operates to break the lump of the garbage and a new surface is generated which contacts with the combustion air, new combustion starts at this point, and the combustion speed of the entire furnace increases. On the other hand, when the surface is covered with garbage containing much moisture, the temperature is lowered, or when the supply of combustion air is interrupted, the combustion is inhibited, and the combustion speed of the entire furnace is reduced. In the waste incineration facility 100, such a variation in the combustion speed constantly occurs. In contrast, in the case of combustion of pulverized coal, oil, or natural gas, the pair of furnace supplies burn out instantaneously, and therefore, if the supply flow rate is fixed, the combustion speed is also fixed.

The measured value y of the waste incineration facility 100 fluctuates due to the fluctuation of the combustion speed q. The variation of both is approximated to equation (2) by a linear equation.

y＝c ₁ ×q···(2)

Hereinafter, the measured value y will be described specifically assuming that it is the steam flow rate, the combustion chamber temperature, and the oxygen concentration of the exhaust gas. These are examples, and the second channel temperature of the boiler, the NOx concentration of the exhaust gas, the CO concentration of the exhaust gas, the primary combustion air flow rate, the secondary combustion air flow rate, and the like may be used. C of equation (2) ₁ Is a coefficient vector of 3 rows and 1 column. c. C ₁ The measured values y indicating the increase in the combustion speed, i.e., the changes in the steam flow rate, the combustion chamber temperature, and the oxygen concentration of the exhaust gas. If the combustion amount increases, the steam flow rate increases, the combustion chamber temperature increases, and the oxygen concentration of the exhaust gas decreases. c. C ₁ Is a vector of coefficients that increases and decreases in quantization.

The formula (2) gives a fluctuation to the measured value y in accordance with the fluctuation of the combustion speed q, but cannot directly calculate the combustion speed q upside down. Hereinafter, a method of estimating the combustion speed from the variation of the measured value y will be described. First, a measurement vector y having measurement values such as a steam flow rate, a combustion chamber temperature, and an oxygen concentration of exhaust gas as column elements is formed, and a variance covariance matrix Q is obtained as shown in equation (3) ₀ . Var (y) represents the variance covariance matrix of vector y。

Q ₀ ＝Var(y)···(3)

Then, the covariance matrix Q ₀ Singular value decomposition is carried out to obtain singular vector u of formula (4) _i (i =1, 2, 3) and singular value σ ² _i (i =1, 2, 3). Here, the singular values are sorted in order of magnitude, as is customary for singular value decomposition. I.e. sigma ² ₁ Is the maximum singular value, σ ² ₃ Is the smallest singular value. The notation T of the right shoulder denotes the transpose of the matrix or vector.

[ numerical formula 2]

Next, assuming that the unknown disturbance ρ is present, the fluctuation of the measurement value y is expressed by a singular vector u and the unknown disturbance ρ as in the following equation (5). The unknown disturbance ρ includes the combustion speed variation q of equation (2) as a component, but the actual situation is not clear. The relationship between the two will be described below. The value of u is determined by the variance covariance matrix Q of the measurement vector y ₀ Singular value decomposition is performed. Assuming that the measurement vector y fluctuates due to the unknown disturbance ρ, the measurement vector y is expressed by a linear combination of ρ as in equation (5). The elements of ρ are denoted ρ i (i =1, 2, 3).

[ numerical formula 3]

Due to the covariance matrix Q ₀ And therefore the singular vector u has the property of equation (6).

[ numerical formula 4]

Therefore, the value of ρ is directly determined as in equation (5A) from equations (5) and (6).

[ numerical formula 5]

The variance-covariance matrix of ρ is equation (7).

[ number 6]

As shown in equation (7), ρ is the first element of unknown external disturbance ₁ Is the maximum singular value σ ₁ ² Therefore, the variation of the measured value vector y is mainly determined by ρ ₁ And (3) causing. This is because depending on the nature of the singular values,

Var(y1)+Var(y2)+Var(y3)＝σ ₁ ² +σ ₂ ² +σ ₃ ² _μ ···(8)

it holds in particular when σ ₁ ² >>σ ₂ ² +σ ₃ ² Then, the equation is approximated by the following equation (8A).

[ number formula 7]

Equation (8A) shows how the measurement vector y fluctuates by ρ ₁ And (4) leading. On the other hand, since it is known that the fluctuation of the measured value of the refuse incineration facility 100 is caused by the fluctuation of the combustion speed, ρ is calculated ₁ It is reasonable to set the estimated value of the combustion speed q. If the value is extracted from equation (5A) with respect to ρ ₁ The part of calculation of (2) obtains equation (9) as an estimation equation of the variation of the combustion speed. According to the equation (9), the estimated value of the combustion speed q can be quickly calculated with a small amount of calculation based on the measured value y.

[ number 8]

As described above, the estimation of the combustion speed q may use the boiler second channel temperature, the CO concentration of the exhaust gas, the NOx concentration of the exhaust gas, the primary combustion air flow rate, the secondary combustion air flow rate, or the like instead of or in addition to the combustion chamber temperature, the oxygen concentration of the exhaust gas, and the steam flow rate.

The above-described method of estimating the combustion speed q is an example, and is not limited thereto. For example, an estimation model for estimating the combustion speed q may be created using a neural network, deep learning, or the like.

The control unit 23 controls the operation of the waste incineration apparatus 100. For example, the amount of garbage supplied to the combustion chamber 6 and the amount of combustion air supplied to the combustion chamber 6 are calculated while monitoring the steam flow rate or the like measured by the steam flow rate sensor 11, and combustion control of garbage is performed by adjusting these amounts. Specifically, the control unit 23 supplies a desired amount of combustion air to the combustion chamber 6 by controlling the rotation speed of the blower 4, the opening degrees of the valves 8A to 8E, and the opening degree of the valve 14A, and supplies a desired amount of garbage to the combustion chamber 6 by controlling the pusher 10. For example, the amount of garbage supplied is calculated based on the deviation between the measured value of the steam flow rate and a set value, and the amount of combustion air supplied is calculated based on the set value of the steam flow rate. In the present invention, in addition to this, the amount of garbage supplied and the amount of combustion air supplied are calculated in consideration of the real-time combustion speed q estimated by the combustion speed estimation unit 22 (the first to sixth embodiments).

The storage unit 24 stores information acquired by the data acquisition unit 21 and information necessary for control, for example, the steam flow rate set value SV.

< first embodiment >

The control of the waste incineration facility 100 according to the first embodiment will be described with reference to fig. 2.

(constitution)

Fig. 2 shows the configuration of the main portions of the combustion speed estimating unit 22 and the control unit 23 in the control device 20. The combustion speed estimation unit 22 estimates the combustion speed q by the above-described procedure. The control unit 23 includes a coefficient calculation table 231 and a PI controller 232. The storage unit 24 records a set value SV of the steam flow rate. The refuse incineration facility 100 is operated so that the steam flow rate measured by the steam flow rate sensor 11 is a set value SV.

The control portion 23 changes the intensity of the feed control in accordance with the combustion speed q. For example, if the PI controller is used to adjust the garbage supply amount, the value of the proportional gain is changed in accordance with the combustion speed q. As shown in the coefficient calculation table 231 of fig. 2, the gain variable coefficient β is set in advance as a function of the combustion speed q. The control unit 23 acquires the coefficient β corresponding to the combustion speed q by referring to the coefficient calculation table 231 based on the combustion speed q. The PI controller 232 receives, for example, a set value (target value) SV of the steam flow rate (t/h) and a measured value PV by the steam flow rate sensor 11, performs PI calculation (proportional integral calculation) on the deviation thereof, and outputs the garbage supply amount (m) ³ H) as MV. In this case, the proportional gain K controlled by PI is expressed by the following equation (10) _P Multiplied by a gain variation coefficient beta.

[ numerical formula 9]

As a modification, when the combustion speed q is small, that is, when the combustion is difficult to burn (the above (b)), the garbage remains without being burned in the furnace, and therefore, it is not necessary to further add garbage. Therefore, for example, the proportional gain for increasing the garbage supply amount in proportion to the steam flow rate deviation is set to be half of the normal gain. When the proportional gain of the PI controller 232 is changed during operation, the controller is usually implemented by a speed-type algorithm. As far as the PI controller 232 is concerned,in addition to the proportional gain, the integration time constant T _I Is also the tuning constant. For integral time constant T _I Similarly to the proportional gain, the proportional gain may be changed in accordance with the combustion speed q. The control unit 23 controls the pushed amount of the pusher 10 based on the MV output from the PI controller 232.

(act)

Next, a flow of processing (waste supply amount control) in the first embodiment will be described with reference to fig. 3.

The data acquisition unit 21, the combustion speed estimation unit 22, and the control unit 23 execute the following processing at predetermined time intervals.

The data acquisition unit 21 acquires: a steam flow PV measured by the steam flow sensor 11; o measured by the oxygen concentration sensor 15 ₂ Concentration; the temperature of the combustion chamber 6 measured by the temperature sensor 16; the temperature of the second channel of the boiler measured by the temperature sensor 17A; the CO concentration of the exhaust gas measured by the CO concentration sensor 17B; the NOx concentration of the exhaust gas measured by the NOx concentration sensor 17C; the primary combustion air flow rate measured by the flow sensor 17D; the flow rate sensor 17E measures the flow rate of the post-combustion air (step S1), and outputs the values to the combustion speed estimating unit 22 and the control unit 23.

The combustion speed estimation unit 22 estimates the combustion speed q by using the equation (9) using the measurement value y of a preferable plurality of (one of) the steam flow rate PV, the oxygen concentration, the combustion chamber temperature, the temperature of the second boiler duct, the CO concentration sensor, the NOx concentration, the primary combustion air flow rate, and the secondary combustion air flow rate (step S2). The combustion speed estimation unit 22 outputs the combustion speed q to the control unit 23.

Next, the control unit 23 calculates the coefficient β based on the combustion speed q and the coefficient calculation table 231. Next, the control unit 23 reads the set value SV of the steam flow rate stored in the storage unit 24, and calculates the garbage supply amount MV based on the calculated coefficient β, the set value SV of the steam flow rate, the steam flow rate PV acquired by the data acquisition unit 21, and the equation (10) (step S3). The controller 23 controls the movement amount (pushed amount) of the pusher 10 so that the garbage feed amount MV can be fed into the furnace.

According to the present embodiment, the combustion speed of refuse in the entire furnace is estimated based on the measured values of the sensors already provided in the refuse incineration facility 100, such as the steam flow rate, the combustion chamber temperature, and the oxygen concentration of the exhaust gas, and the set value (gain) of the PI controller 232 that feeds back the deviation between the set value of the steam flow rate and the measured values to the refuse supply is changed. This makes it possible to equalize the flow rate of steam to the turbine, increase the amount of power generation, and stabilize the amount of power generation. Further, the stabilization of combustion in the combustion chamber 6 can suppress the emission of NOx, CO, and the like.

Further, according to the present embodiment, (E1) the combustion speed q of refuse is estimated from the measured values of the sensors (sensors reflecting the fluctuation of the combustion speed) already provided in the refuse incineration facility 100, such as the steam flow rate, the combustion chamber temperature, and the oxygen concentration of the exhaust gas, so that it is not necessary to add a new sensor. (E2) By using the amount of heat generation depending on the amount of garbage supplied as an index and not paying attention to a specific element such as moisture of garbage which is a cause of variation in the amount of heat generation, but using the combustion rate independent of the amount of garbage supplied as an index, the effect is not limited to the specific element paid attention to, and even when the combustion state varies due to various factors, the variation can be detected and combined with the control (the effect is not limited). (E3) If the index of control is the amount of heat generation corresponding to the amount of garbage supplied, an error occurs in the estimation of the amount of heat generation due to the time difference from garbage supply to combustion. The calorific value is a calorific value per unit mass of supplied garbage, and the combustion rate indicates heat generation of the entire furnace and does not depend on the mass of the garbage located in the furnace. This prevents the occurrence of an error when the amount of heat generation is used as a control target. The effect is obtained.

< second embodiment >

The control of the waste incineration facility 100 according to the second embodiment will be described with reference to fig. 4 and 5.

(constitution)

Fig. 4 is a diagram showing an example of a functional configuration of a main part of the control device of the second embodiment.

Fig. 4 shows the configuration of the main portions of the combustion speed estimating unit 22 and the control unit 23A in the control device 20. The combustion speed estimation unit 22 estimates the combustion speed q by the above-described procedure. The control unit 23A includes a primary combustion air valve adjustment amount calculation table 233 and an adder 234. The storage unit 24 stores a set value SV of the steam flow rate and the opening degrees of the valves 8A to 8E and the valve 14A as references with respect to the set value SV.

The second embodiment is effective mainly when the combustion in the furnace is excessively active, that is, when the combustion speed q is high. The waste incineration facility 100 is supplied with combustion air by the blower 4. A part of the air passes through the waste layer deposited on the grate 3 from bottom to top through the air boxes 5A to 5E as primary combustion air, and then flows into the combustion chamber 6. When the primary combustion air passes through the refuse layer, a part of the primary combustion air is used for combustion in the refuse layer, and combustible pyrolysis gas generated in the refuse layer due to heat generation thereof is sent to the combustion chamber 6 together with the primary combustion air and is combusted in the combustion chamber 6. In this way, the primary combustion air refuse layer is supplied to function as a generator of thermal decomposition gas. Therefore, if the primary combustion air is restricted, the generation of thermal decomposition gas is reduced, and the combustion speed in the furnace can be reduced. The heat generation regulation in the furnace by the regulation of the primary combustion air is effective particularly when the combustion speed q is large. In such a situation, a sufficient amount of refuse is present in the furnace, and the supply and combustion of refuse may be excessively stopped. At this time, it is necessary to restrict the combustion of the garbage present in the furnace. Therefore, the restriction of the primary combustion air is effective. On the contrary, when the combustion in the furnace is insufficient, i.e., the combustion speed q is small, it is effective to increase the generation of the thermal decomposition gas by increasing the primary combustion air. As a result, the supply of the thermally decomposed gas to the combustion chamber 6 increases, and the combustion speed q increases. The control according to the second embodiment functions to suppress the variation in the combustion speed q in this manner.

The opening of the primary combustion air valve determines a reference value according to a set value SV of the steam flow and the like. As shown in fig. 4, the adjustment amount calculation table 233 for the primary combustion air valve specifies the relationship between the combustion speed q and the correction amount Δ γ 1 with respect to the reference value of the primary combustion air valve opening from the set value SV. The control unit 23 calculates an adjustment amount Δ γ 1 of the valve opening of the primary combustion air based on the combustion speed q and the adjustment amount calculation table 233. The value of the adjustment amount Δ γ 1 is set to be large when the value of the combustion speed q is small and small when the value of the combustion speed q is large. The control unit 23 adds the adjustment amount Δ γ 1 to the reference value of the opening degree of the primary combustion air valve by using the adder 244, thereby adjusting the opening degree of the primary combustion air valve. The control unit 23 controls the valves 8A to 8E based on the adjusted primary combustion air valve opening.

(action)

Next, a flow of processing (flow rate control of primary combustion air) in the second embodiment will be described with reference to fig. 5.

The data acquisition unit 21, the combustion speed estimation unit 22, and the control unit 23A execute the following processing at predetermined time intervals.

The data acquisition unit 21 acquires: steam flow PV, O ₂ The concentration, the combustion chamber temperature, the temperature of the second boiler duct, the CO concentration, the NOx concentration, the primary combustion air flow rate, and the secondary combustion air flow rate (step S1), and these measured values are output to the combustion speed estimating unit 22 and the control unit 23A.

The combustion speed estimator 22 uses the steam flow rates PV and O ₂ The combustion speed q is estimated by the equation (9) from a plurality of measured values y of the concentration, the combustion chamber temperature, the temperature of the second path of the boiler, the CO concentration sensor, the NOx concentration, the primary combustion air flow rate, and the secondary combustion air flow rate (step S2). The combustion speed estimation unit 22 outputs the estimated combustion speed q to the control unit 23A.

Next, the controller 23A calculates the adjustment amount Δ γ 1 of the valve opening of the primary combustion air based on the combustion speed q and the adjustment amount calculation table 233. Next, the controller 23A adds the reference value of the valve opening of the primary combustion air corresponding to the set value SV of the steam flow rate stored in the storage unit 24 and the adjustment amount Δ γ 1 by using the adder 234, and calculates the valve opening of the primary combustion air (step S4). The controller 23A controls the valves 8A to 8E so that the opening degrees thereof become the adjusted valve opening degrees of the primary combustion air.

According to the present embodiment, the combustion speed q of refuse is estimated based on the measurement values measured by the sensors already provided in the refuse incineration facility 100, such as the steam flow rate, the combustion chamber temperature, and the oxygen concentration of the exhaust gas, and the primary combustion air flow rate is adjusted based on the combustion speed q. This can suppress the fluctuation of the combustion speed q. Further, the effects (E1) to (E3) can be obtained as in the first embodiment. The second embodiment can be combined with the first embodiment.

In fig. 4, the primary combustion air is adjusted by adjusting the valve opening of the primary combustion air as an example, but as another method, the command value of the primary combustion air flow rate may be adjusted by controlling the flow rate of the primary combustion air flow rate with the command value. Alternatively, the original pressure (upstream pressure) of the primary combustion air may be adjusted.

< third embodiment >

The control of the waste incineration facility 100 according to the third embodiment will be described with reference to fig. 6 and 7.

(constitution)

Fig. 6 shows the configuration of the main portions of the combustion speed estimating unit 22 and the control unit 23B in the control device 20. The combustion speed estimation unit 22 estimates the combustion speed q by the above-described procedure. The control unit 23B includes a primary combustion air valve adjustment amount calculation table 233, an adder 234, a secondary combustion air valve adjustment amount calculation table 235, and an adder 236. The set value SV of the steam flow rate and the opening degrees of the valves 8A to 8E and the valve 14A, which are references to the set value SV, are recorded in the storage unit 24.

Third embodiment except for the first time explained in the second embodimentIn addition to the opening control of the combustion air valve, the opening control of the secondary combustion air valve is also performed. The combustion speed q of the garbage is temporarily set to be excessively high. At this time, the generation of the thermally decomposed gas in the furnace is temporarily excessive, and as a result, O of the exhaust gas of the waste incineration facility 100 is temporarily excessive ₂ The concentration is temporarily insufficient. If O of exhaust gas ₂ If the concentration is insufficient, the risk of discharging harmful substances such as CO increases. Therefore, in the third embodiment, while the primary combustion air is adjusted based on the combustion speed q, the secondary combustion air is also adjusted to supplement O ₂ The concentration is insufficient. For example, the primary combustion air is reduced to suppress the generation of thermal decomposition gas when the combustion speed q is excessively large, and the secondary combustion air is increased for burning the excessively generated thermal decomposition gas. On the contrary, when the combustion speed q is too small, the generation of the thermal decomposition gas is promoted by adding the primary combustion air. The amount of secondary combustion air generated is excessive relative to the amount of thermal decomposition gas, and therefore, is reduced. This is also useful to avoid the production of NOx.

As shown in fig. 6, the adjustment amount calculation table 235 for the secondary combustion air valve determines the relationship between the combustion speed q and the correction amount Δ γ 2 with respect to the reference value of the secondary combustion air valve opening amount. The control unit 23B calculates an adjustment amount Δ γ 2 of the valve opening of the secondary combustion air based on the combustion speed q and the adjustment amount calculation table 235. The value of the adjustment amount Δ γ 2 is set to be small when the value of the combustion speed q is small and large when the value of the combustion speed q is large. The control section 23B adds the adjustment amount Δ γ 2 to the reference value of the secondary combustion air valve opening using the adder 245 to adjust the secondary combustion air valve opening. The control unit 23B controls the valve 14A based on the adjusted opening degree of the post-combustion air valve.

(action)

Next, a flow of processing (flow rate control of the primary combustion air and the secondary combustion air) in the third embodiment will be described with reference to fig. 7.

The data acquisition unit 21, the combustion speed estimation unit 22, and the control unit 23B execute the following processing at predetermined time intervals.

The data acquisition unit 21 acquires a measurement value such as the steam flow rate PV (step S1), and outputs the measurement value to the combustion speed estimation unit 22 and the control unit 23B. Next, the combustion speed estimation unit 22 estimates the combustion speed q (step S2). Combustion speed estimation unit 22 outputs combustion speed q to control unit 23B.

Next, the control unit 23B calculates the adjustment amount Δ γ 1 of the opening degree of the primary combustion air valve based on the combustion speed q and the adjustment amount calculation table 233. Next, the control unit 23 adds the reference value of the primary combustion air valve opening corresponding to the set value SV of the steam flow rate stored in the storage unit 24 and the adjustment amount Δ γ 1 by using the adder 234, and calculates the primary combustion air valve opening (step S4). The controller 23 controls the valves 8A to 8E so that the opening degrees thereof become the adjusted valve opening degrees of the primary combustion air.

Further, the control portion 23B calculates an adjustment amount Δ γ 2 of the secondary combustion air valve opening degree based on the combustion speed q and the adjustment amount calculation table 235. Next, the control unit 23 adds the reference value of the secondary combustion air valve opening corresponding to the set value SV of the steam flow rate stored in the storage unit 24 and the adjustment amount Δ γ 2 by using the adder 236, and calculates the valve opening of the secondary combustion air (step S5). The controller 23 controls the valve 14A so that the opening degree thereof becomes the adjusted valve opening degree of the secondary combustion air. The processing sequence of steps S4 to S5 may be arbitrary, and for example, the control unit 23B may execute the processing of steps S4 to S5 in parallel at the same time.

According to the present embodiment, the combustion speed q of refuse is estimated based on the measured values of the sensors already provided in the refuse incineration facility 100, such as the steam flow rate, the combustion chamber temperature, and the oxygen concentration of the exhaust gas, and the primary combustion air flow rate and the secondary combustion air flow rate are adjusted based on the combustion speed q of refuse. Thus, the secondary combustion air is adjusted according to the amount of the generated thermal decomposition gas, thereby helping complete combustion of the thermal decomposition gas and suppressing discharge of harmful substances such as CO and NOx. Further, the effects (E1) to (E3) can be obtained as in the first embodiment. The third embodiment can be combined with the first embodiment.

< fourth embodiment >

The control of the refuse incineration power generation plant 100 according to the fourth embodiment will be described with reference to fig. 8.

(constitution)

Fig. 8 is a diagram showing an example of a functional configuration of a main part of a control device according to a fourth embodiment.

Fig. 8 shows the configuration of the main portions of the combustion speed estimating unit 22 and the control unit 23C in the control device 20. The combustion speed estimation unit 22 estimates the combustion speed q by the above-described procedure. The control unit 23C includes a wind box distribution adjustment opening degree calculation table 237, an adder 238, and a subtractor 239. The opening degrees of the valves 8A to 8E, which are references to the set value SV of the steam flow rate, are recorded in the storage unit 24.

In the fourth embodiment, in order to suppress the variation in the combustion speed q, the amount of combustion air supplied to the windboxes 5A to 5E is set to be different in the opening degree control of the primary combustion air valve in consideration of the combustion tendency of the refuse in the combustion chamber 6. The waste layer has an aspect as a generator of thermal decomposition gas. The amount of the generation capacity of the thermally decomposed gas depends on the positions of the windboxes 5A to 5E. Since the

bellows

5A and 5B close to the pusher 10 have a large thickness of the waste layer before thermal decomposition, the generating ability of the thermal decomposition gas is high. On the other hand, as the

wind boxes

5C, 5D, 5E and the garbage advance on the grate 3, the proportion of the thermally decomposed garbage and the burned dust increases, and the generating capacity of the thermally decomposed gas decreases. Therefore, when the estimated combustion speed q is small, that is, when the combustion of the refuse is difficult, more primary combustion air is distributed to the wind box 5A or the like close to the pusher 10 having a high ability to generate the thermal decomposition gas, whereas when the estimated value q of the combustion speed is large, that is, when the refuse is inflammable, the distribution of the primary combustion air to the wind box 5A or the like having a high ability to generate the thermal decomposition gas is reduced, and the combustion is suppressed.

FIG. 8 shows the configuration of the case where the wind boxes A and B are classified into a group having a high thermal decomposition gas generating ability, and the wind boxes C and D are classified into a group having a low thermal decomposition gas generating ability. As shown in FIG. 8, the windbox distribution adjustment opening calculation table 237 specifies the combustion speed q and the correction amount Deltay relative to the reference value of the valve openings of the windboxes 5A to 5B and the windboxes 5C to 5E _ABCDE Is onIs described. The control unit 23C calculates adjustment amounts Δ γ of the opening degrees of the valves 8A to 8E based on the combustion speed q and the bellows distribution adjustment opening degree calculation table 237 _ABCDE . Adjustment quantity delta gamma _ABCDE The value of (b) is set to be large when the combustion speed q is small and small when the combustion speed q is large. The control unit 23C uses the adder 238 to adjust the adjustment amount Δ γ _ABCDE To the reference value of the opening degree of the valves 8A to 8B. The control unit 23C uses the subtractor 239 to adjust the adjustment amount Δ γ _ABCDE The opening degree of the valves 8C to 8E is subtracted from a reference value. The controller 23B controls the valves 8A to 8E based on the adjusted valve opening degrees.

In fig. 8, the air boxes 5A to 5B are set as one set, and the air boxes 5C to 5E are set as one set, but this is merely an example. Instead of grouping the windboxes 5A to 5E, the windbox distribution adjustment opening degree calculation table 237 may be provided for each of the windboxes to adjust the opening degrees of the valves 8A to 8E, or the grouping method may be changed to, for example, the windboxes 5A to 5C and the windboxes 5D to 5E. The number of groups to be classified may be three, and for example, the groups may be classified into the wind boxes 5A to 5B, 5C to 5D, and 5E.

(action)

The flow of the processing of the fourth embodiment will be described with reference to fig. 5 of the second embodiment.

The data acquisition unit 21, the combustion speed estimation unit 22, and the control unit 23C execute the following processing at predetermined time intervals.

The data acquisition unit 21 acquires a measurement value such as the steam flow rate PV (step S1), and outputs the measurement value to the combustion speed estimation unit 22 and the control unit 23C. Next, the combustion speed estimation unit 22 estimates the combustion speed q (step S2). The combustion speed estimation unit 22 outputs the combustion speed q to the control unit 23C.

Subsequently, the control unit 23C calculates the adjustment amount Δ γ based on the combustion speed q and the bellows distribution adjustment opening degree calculation table 237 _ABCDE . Next, the control unit 23 compares the reference value of the valve opening degree of the valves 8A to 8E corresponding to the set value SV of the steam flow stored in the storage unit 24 with the adjustment amount Δ γ _ABCDE Addition and subtraction calculation is performed to calculate the valve opening of the primary combustion air (step S4). In the case of the configuration example of fig. 8, the control unit23 adjust the amount of opening of the valves 8A to 8B by Δ γ _ABCDE Added to the reference value. The control unit 23 subtracts the adjustment amount Δ γ from the reference value for the opening degrees of the valves 8C to 8E _ABCDE . The controller 23 controls the valve openings of the valves 8A to 8E so that the adjusted valve openings are obtained.

According to the fourth embodiment, the combustion speed q of the refuse is estimated based on the measured values of the sensors already provided in the refuse incineration facility 100, such as the steam flow rate, the combustion chamber temperature, and the oxygen concentration of the exhaust gas, and the ratio of the flow rate at which the primary combustion air is distributed to the wind boxes is adjusted based on the estimated combustion speed q of the refuse. This can suppress the variation in the combustion speed q with high accuracy. Further, the effects (E1) to (E3) can be obtained as in the first embodiment. The fourth embodiment can be combined with the first and third embodiments.

< fifth embodiment >

The control of the waste incineration power generation plant 100 according to the fifth embodiment will be described with reference to fig. 9 and 10.

(constitution)

Fig. 9 shows the configuration of the main portions of the combustion speed estimating unit 22 and the control unit 23D in the control device 20.

The combustion speed estimation unit 22 estimates the combustion speed q by the above-described procedure. The control unit 23D includes a variance calculator 240, an oxygen concentration adjustment amount calculation table 241, an oxygen concentration controller 242, adders 243 to 245, and a subtractor 246. The opening degrees O, which are references of the valves 8A to 8E and the valve 14A with respect to the set value SV of the steam flow rate, are recorded in the storage unit 24 ₂ Set value of concentration SV _ O ₂ 。

In the third embodiment described above, the flow rate of the secondary combustion air is adjusted while adjusting the flow rate of the primary combustion air based on the combustion speed q of the refuse. One of the reasons for adjusting the secondary combustion air is to reduce the CO concentration in the combustion chamber 6. For example, in the case of regulation in such a way that the primary combustion air is reduced, there is a lack of combustion in the refuse layerThe CO concentration in the thermally decomposed gas increases by burning air. Thus, the secondary combustion air is increased to completely combust CO in the combustion chamber 6, thereby reducing the CO concentration. However, if the combustion speed of the garbage is increased rapidly with time, there is a possibility that the adjustment of the primary combustion air and the secondary combustion air is delayed in time and the CO is discharged temporarily. Such a rapid increase in the combustion speed is considered to depend on the nature of the supplied waste. It is empirically known that a rapid increase in combustion speed, once generated, is concentrated over a short period of time. Therefore, in the fifth embodiment, when the combustion speed q varies, the flow rate of the secondary combustion air or the primary combustion air is increased in advance to maintain the exhaust gas O ₂ The concentration is high, and shortage of combustion air can be avoided even if the combustion speed q is increased to prevent discharge of CO.

The variance calculator 240 calculates a variance σ of a predetermined time immediately before the combustion speed q estimated by the combustion speed estimation unit 22 _q ² . As shown in FIG. 9, the variance σ is determined in the oxygen concentration adjustment amount calculation table 241 _q ² And oxygen concentration adjustment amount DeltaGamma _SVO2 The relationship (c) in (c). Adjustment quantity delta gamma _SVO2 The values of (A) are set as: when variance σ _q ² Is 0 when the value of (b) is less than the threshold value, and is 0 when the variance σ is smaller than the threshold value _q ² When the value of (A) is equal to or greater than the threshold value, the predetermined value is set as the upper limit, and the variance σ is increased _q ² Becomes larger up to its upper limit value. Oxygen concentration controller 242 based on adjusted O ₂ Concentration set value SV _ O ₂ And O ₂ Concentration measurement PV _ O ₂ The deviation of the concentration is used to calculate the primary combustion air valve adjustment opening and the secondary combustion air valve adjustment opening. For example, the oxygen concentration controller 242 calculates the adjustment opening degree that requires increasing the primary combustion air valve adjustment opening degree and the secondary combustion air valve adjustment opening degree as the deviation is larger.

(act)

The flow of the processing in the fifth embodiment will be described with reference to fig. 10.

The data acquisition unit 21, the combustion speed estimation unit 22, and the control unit 23D execute the following processing at predetermined time intervals.

The data acquisition unit 21 acquires a measurement value such as the steam flow rate PV (step S1), and outputs the measurement value to the combustion speed estimation unit 22 and the control unit 23D. Next, the combustion speed estimation unit 22 estimates the combustion speed q (step S2). The combustion speed estimation unit 22 outputs the combustion speed q to the control unit 23D.

Subsequently, the control unit 23D calculates the variance σ of the combustion speed q using the variance calculator 240 _q ² (step S6). The control unit 23D calculates the variance σ _q ² To calculate the offset O ₂ The opening degree of the primary combustion air valve and the opening degree of the secondary combustion air valve for the concentration (step S7). First, the control unit 23D calculates the variance σ _q ² And the oxygen concentration adjustment amount calculation table 241 calculates O ₂ Adjustment amount of concentration Δ γ _SVO2 . Then, the adder 243 adds O ₂ Adjustment amount of concentration Δ γ _SVO2 Added to O ₂ Set value for concentration SV _ O ₂ . Next, subtractor 246 derives from the adjusted SV _ O ₂ Subtracting a measured value PV _ O measured by an oxygen concentration sensor 15 ₂ . Oxygen concentration controller 242 then bases on the adjusted O ₂ Concentration set value SV _ O ₂ And O ₂ Concentration measurement PV _ O ₂ The deviation of the concentration is used to calculate the primary combustion air valve adjustment opening and the secondary combustion air valve adjustment opening. Next, the controller 23D adds the primary combustion air valve adjustment opening and the primary combustion air valve reference value corresponding to the set value SV of the steam flow rate and calculates the primary combustion air valve opening by using the adder 244. The controller 23D controls the valves 8A to 8E so that the opening degrees thereof become the calculated opening degrees. Next, the controller 23D adds the reference value of the valve opening of the secondary combustion air corresponding to the set value SV of the steam flow rate and the secondary combustion air valve adjustment opening by using the adder 245, and calculates the valve opening of the secondary combustion air. The controller 23D controls the valve 14A so that the opening degree thereof becomes the calculated opening degree.

According to the present embodiment, the steam flow rate, the combustion chamber temperature, the oxygen concentration of the exhaust gas, and the like have been setThe combustion speed q of refuse is estimated from the measurement value of a sensor provided in the refuse incineration facility 100, and O in exhaust gas is corrected based on the variance of the combustion speed q ₂ The set value of the concentration adjusts the flow rate of the primary combustion air and the secondary combustion air according to the set value. This can suppress the discharge of CO gas. Further, the effects (E1) to (E3) can be obtained as in the first embodiment. The fifth embodiment can be combined with the first to fourth embodiments.

< sixth embodiment >

Next, the control of the refuse incineration power generation plant 100 according to the sixth embodiment will be described with reference to fig. 11.

Fig. 11 shows the configuration of the main portions of the combustion speed estimating unit 22 and the control unit 23E in the control device 20. The combustion speed estimation unit 22 estimates the combustion speed q by the above-described procedure. The control unit 23E includes a combustion speed commander 247, a combustion speed controller 248, a subtractor 249, a primary combustion air valve adjustment amount calculation table 233, an adder 234, a secondary combustion air valve adjustment amount calculation table 235, and an adder 236. The configuration illustrated in fig. 11 is combined with the control unit 23B (the table 233 for calculating the adjustment amount of the primary combustion air valve, the adder 234, the table 235 for calculating the adjustment amount of the secondary combustion air valve, and the adder 236) of the third embodiment.

The combustion speed commander 247 calculates a command value qsv for adjusting the combustion speed q estimated by the combustion speed estimation unit 22 based on a deviation (SV-PV) between the set value SV of the steam flow rate and the measured value PV of the steam flow rate. The command value qsv commands the combustion speed of garbage to match the measured value PV of the steam flow rate with a set value SV which is a target value of the steam flow rate. By setting the combustion speed of qsv corresponding to the command value, the steam flow PV can be controlled to the target value SV with high accuracy. For example, the combustion speed commander 247 includes a correspondence table between the steam flow rate deviation (SV-PV) and the adjustment amount of the combustion speed q, and calculates a combustion speed command for adjusting the combustion speed q based on the correspondence tableThe value qsv. The combustion speed controller 248 acquires the combustion speed command value qsv and the combustion speed q estimated by the combustion speed estimation unit 22, corrects the combustion speed q by, for example, the following equation (11), and outputs the corrected combustion speed q ^～。

q ^～＝q+Kq(qsv-q)···(11)

Here, kq is a coefficient of an arbitrary value.

Corrected combustion speed q ^～ For example, the same as in the third embodiment is used for the adjustment of the primary combustion air and the secondary combustion air. For example, the control unit 23E calculates the corrected combustion speed q ^～ And a primary combustion air valve adjustment amount calculation table 233, and an adjustment amount Δ γ 1, and an adjustment amount Δ γ 2 is calculated based on the corrected combustion speed q — and a secondary combustion air valve adjustment amount calculation table 235.

(action)

The flow of the process of the sixth embodiment will be described with reference to fig. 12.

The data acquisition unit 21 acquires a measurement value such as the steam flow rate PV (step S1), and outputs the measurement value to the combustion speed estimation unit 22 and the control unit 23E. Next, the combustion speed estimation unit 22 estimates the combustion speed q (step S2). The combustion speed estimation unit 22 outputs the combustion speed q to the control unit 23E.

Subsequently, the control unit 23E corrects the combustion speed q (step S8). Specifically, the control unit 23E subtracts the measured value PV from the set value SV of the steam flow rate using the subtractor 249. The control unit 23E inputs a deviation (SV-PV) between the set value SV and the measured value PV to the combustion speed commander 247. The combustion speed commander 247 calculates a combustion speed command value qsv. The control unit 23E inputs the combustion speed command value qsv and the combustion speed q to the combustion speed controller 248. The combustion speed controller 248 calculates the corrected combustion speed q by equation (11) ^～ . The control unit 23E uses the corrected combustion speed q ^～ By calculation of the amount of garbage supplied (first embodiment), the opening degree of the primary combustion air valve, and the opening degree of the secondary combustion air valveThe combustion control of the refuse incineration power generation facility 100 is performed by calculation of the degree (second to fifth embodiments) and the like.

According to the present embodiment, the combustion speed q of refuse is estimated based on the measured values of the sensors already provided in the refuse incineration facility 100, such as the steam flow rate, the combustion chamber temperature, and the oxygen concentration of the exhaust gas, and the command value of the combustion speed of refuse is calculated so that the combustion speed q of refuse matches the command value. This makes it possible to control the steam flow rate PV to the set value SV with high accuracy while suppressing the variation in the combustion speed q. The sixth embodiment can be combined with the first to fifth embodiments.

The computer 900 includes a CPU901, a main storage 902, an auxiliary storage 903, an input/output interface 904, and a communication interface 905.

The control device 20 described above is mounted on the computer 900. The above-described functions are stored in the auxiliary storage device 903 as a program. The CPU901 reads a program from the auxiliary storage device 903 and expands the program to the main storage device 902, and executes the above-described processing in accordance with the program. Further, the CPU901 secures a storage area in the main storage 902 according to a program. Further, the CPU901 secures a storage area for storing data in the process in the auxiliary storage 903 according to a program.

Note that a program for realizing all or part of the functions of the control device 20 may be stored in a computer-readable storage medium, and the program stored in the storage medium may be read into a computer system and executed to perform the processing of each functional unit. The "computer system" referred to herein is configured to: including hardware such as an Operating System (OS), peripheral devices, and the like. Note that, if the WWW system is used as the "computer system", the "homepage providing environment (or display environment) is also included. The "computer-readable storage medium" refers to a portable medium such as a CD, DVD, or USB, and a storage device such as a hard disk built in a computer system. When the program is distributed to the computer 900 via a communication line, the computer 900 receiving the distribution may deploy the program in the main storage 902 to execute the above-described processing. The program may be a program for realizing a part of the above-described functions, or may be a program that can be realized in combination with a program in which the above-described functions are stored in a computer system.

As described above, the embodiments of the present invention have been described, and all of the embodiments are provided as examples and are not intended to limit the scope of the invention. These embodiments may be implemented in other various ways, and various omissions, substitutions, and changes may be made without departing from the spirit of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalent scope thereof.

< accompanying notes >

The control device 20, the waste incineration facility 100, the control method, and the program described in each embodiment can be grasped as follows, for example.

(1) The control device 20 according to the first aspect includes: a data acquisition unit 21 that acquires a measurement value measured by a sensor provided in the waste incineration facility; a combustion speed estimation unit 22 for estimating a combustion speed q in an incinerator (combustion chamber 6) of the waste incineration facility using the measured value; and a control unit 23 for controlling the amount of garbage supplied or the flow rate of combustion air supplied to the incinerator based on the combustion speed.

Thus, the variation in combustion of the entire waste incinerator is detected as the combustion rate, and control can be performed in accordance with the combustion rate, so that stable operation can be achieved by suppressing the variation in combustion rate. For example, supplying a fixed steam flow rate to a turbine for power generation can contribute to stabilization of power generation and increase in power generation. Further, the stabilization of combustion can suppress the emission of NOx, CO, and the like.

(2) The control device 20 according to the second aspect is the control device 20 according to (1), wherein the combustion speed estimating unit multiplies the measurement value by a maximum singular vector corresponding to a maximum singular value obtained by singular value decomposition of a variance covariance matrix of the measurement value used for estimation of the combustion speed, and estimates the combustion speed (equation (9)).

This makes it possible to calculate the combustion speed q with a small calculation load, and therefore, the current combustion speed q can be estimated immediately after the measurement value is acquired.

(3) The control device 20 according to the third aspect is the control device 20 according to any one of (1) to (2), wherein the control unit adjusts the magnitude of the gain of the feedback controller based on the combustion speed, for calculating the garbage supply amount for compensating for the deviation between the target value of the steam flow rate output from the garbage incineration facility and the measured value of the steam flow rate.

By controlling the amount of garbage supplied, the variation in the combustion speed can be suppressed (first embodiment).

(4) The control device 20 according to the fourth aspect is the control device 20 according to any one of (1) to (3), and the control unit multiplies the gain by a value smaller than 1 when the combustion speed is smaller than a predetermined threshold value.

When the combustion speed is lowered due to an excessive amount of garbage supplied, the combustion speed can be recovered by controlling the amount of garbage supplied (first embodiment).

(5) The control device 20 according to the fifth aspect is the control device 20 according to any one of (1) to (4), wherein the control unit controls an opening degree of a primary combustion air valve that controls a flow rate of primary combustion air supplied to the primary combustion chamber, in accordance with the magnitude of the combustion speed, as follows: and when the combustion speed is lower than the predetermined threshold value, the opening degree of the primary combustion air valve is made larger than a reference value, wherein the primary combustion chamber is a space in the incinerator for incinerating garbage.

For example, the amount of the primary combustion air supplied is decreased when the combustion is strong, and the amount of the primary combustion air supplied is increased when the combustion is low, whereby the combustion of the garbage in the combustion chamber 6 can be stabilized (second embodiment).

(6) The controller 20 according to the sixth aspect is the controller 20 of (5), wherein the controller increases the primary combustion air supplied to a position close to the garbage injection port in the primary combustion chamber by more than a predetermined reference value when the combustion speed is smaller than a predetermined threshold value, and decreases the primary combustion air supplied to a position close to the garbage injection port in the primary combustion chamber by more than a predetermined reference value when the combustion speed is larger than the predetermined threshold value.

By adjusting the amount of primary combustion air supplied to each windbox in accordance with the generation capacity of the thermal decomposition gas, the combustion speed can be stabilized more effectively (fourth embodiment).

(7) The control device 20 according to the seventh aspect is the control device 20 according to any one of (1) to (6), wherein the control unit controls an opening degree of a secondary combustion air valve that controls a flow rate of the combustion air supplied to the secondary combustion chamber, in accordance with the magnitude of the combustion speed, as follows: and a secondary combustion air valve opening degree control unit configured to control an opening degree of the secondary combustion air valve to be larger than a reference value when the combustion speed is larger than a predetermined threshold value, and to control the opening degree of the secondary combustion air valve to be smaller than the reference value when the combustion speed is smaller than the predetermined threshold value, wherein the secondary combustion chamber is a space in the incinerator where combustion gas generated by burning of garbage is burned.

The risk of CO, nox, etc. emissions can be reduced (third embodiment).

(8) The control device 20 according to the eighth aspect is the control device 20 according to any one of (1) to (7), wherein the control unit increases the flow rate of the combustion air when the variance of the combustion speed is equal to or greater than a predetermined threshold value.

Maintaining O in exhaust gas ₂ The concentration is high, and even if the combustion speed is increased, the shortage of combustion air can be avoided, and the discharge of CO can be suppressed (fifth embodiment).

(9) The control device 20 according to the ninth aspect is the control device 20 according to any one of (1) to (8), in which the control unit calculates a command value of the combustion speed for compensating for a deviation between the target value of the steam flow rate output from the waste incineration facility and the measured value of the steam flow rate, and corrects the combustion speed estimated by the combustion speed estimating unit based on the command value.

Thus, the control object of controlling the steam flow rate output from the refuse burning facility to be a target value can be achieved more accurately while suppressing the variation of the combustion speed.

(10) A waste incineration apparatus according to a tenth aspect includes: an incinerator (combustion chamber 6) for incinerating garbage; a waste feeding device (pusher 10) for feeding waste to the incinerator; a blower 4 for supplying combustion air to the incinerator; combustion air valves (8A-8E, 14E) for controlling the flow rate of combustion air supplied from the blower to an incinerator for incinerating refuse in the incinerator; and the control devices described in (1) to (9).

(11) The control method of the eleventh aspect includes: a step of acquiring a measurement value measured by a sensor provided in the waste incineration apparatus; estimating a combustion speed in an incinerator of the waste incineration facility using the measurement value; and controlling the amount of garbage supplied or the flow rate of combustion air supplied to the incinerator based on the combustion speed.

(12) The program of the twelfth aspect causes a computer to execute: a step of acquiring a measurement value measured by a sensor provided in the waste incineration facility; estimating a combustion speed in an incinerator of the refuse incineration facility using the measurement value; and controlling the amount of garbage supplied or the flow rate of combustion air supplied to the incinerator based on the combustion speed.

Description of the reference numerals

100: a waste incineration device;

1: a hopper;

2: a chute;

3: a grate;

3A: a drying zone;

3B: a combustion zone;

3C: a post-combustion zone;

4: a blower;

5A to 5E: an air box;

6: a combustion chamber;

6A: a primary combustion chamber;

6B: a secondary combustion chamber;

7: an ash outlet;

8A to 8E, 4A: a valve;

9: a boiler;

10: a pusher;

11: a steam flow sensor;

12: a flue;

13. 14: a pipeline;

15: an oxygen concentration sensor;

16. 17A: a temperature sensor;

17B: a CO concentration sensor;

17C: a NOx concentration sensor;

17D: a flow sensor;

17E: a flow sensor;

20: a control device;

21: a data acquisition unit;

22: a combustion speed estimation unit;

23. 23A, 23B, 23C, 23D, 23E: a control unit;

24: a storage unit;

900: a computer;

901：CPU；

902: a main storage device;

903: a secondary storage device;

904: an input/output interface;

905: a communication interface.

Claims

1. A control device is provided with:

a data acquisition unit that acquires a measurement value measured by a sensor provided in the waste incineration facility;

a combustion speed estimating unit for estimating a combustion speed in an incinerator of the refuse burning facility, using the measurement value; and

and a control unit for controlling the amount of garbage supplied or the flow rate of combustion air supplied to the incinerator based on the combustion speed.

2. The control device according to claim 1,

the combustion speed estimating unit estimates the combustion speed by multiplying the measurement value by a maximum singular vector corresponding to a maximum singular value obtained by singular value decomposition of a variance covariance matrix of the measurement value used for estimation of the combustion speed.

3. The control device according to claim 1 or 2,

the control unit adjusts the magnitude of the gain of the feedback controller based on the combustion speed, for a feedback controller that calculates a refuse supply amount that compensates for a deviation between a target value of a steam flow rate output by the refuse incineration facility and the measured value of the steam flow rate.

4. The control device according to claim 3,

when the combustion speed is smaller than a predetermined threshold value, the control unit multiplies the gain by a value smaller than 1.

5. The control device according to any one of claims 1 to 4,

the control unit controls the opening of a primary combustion air valve that controls the flow rate of primary combustion air supplied to the primary combustion chamber, in accordance with the magnitude of the combustion speed, as follows: and when the combustion speed is lower than the predetermined threshold value, the opening degree of the primary combustion air valve is made larger than a reference value, wherein the primary combustion chamber is a space in the incinerator for incinerating garbage.

6. The control device according to claim 5,

the control unit increases the primary combustion air supplied to a position close to the refuse inlet port in the primary combustion chamber by a predetermined reference value when the combustion speed is smaller than a predetermined threshold value, and decreases the primary combustion air supplied to a position close to the refuse inlet port in the primary combustion chamber by a predetermined reference value when the combustion speed is larger than the predetermined threshold value.

7. The control device according to any one of claims 1 to 6,

the control unit controls an opening degree of a secondary combustion air valve that controls a flow rate of combustion air supplied to a secondary combustion chamber, in accordance with a magnitude of the combustion speed, as follows: and a secondary combustion air valve that is opened to a greater degree than a reference value when the combustion speed is greater than a predetermined threshold value, and that is opened to a lesser degree than a reference value when the combustion speed is less than the predetermined threshold value, wherein the secondary combustion chamber is a space in the incinerator where combustion gas generated by the incineration of refuse is combusted.

8. The control device according to any one of claims 1 to 7,

the control unit increases the flow rate of the combustion air when the variance of the combustion speed is equal to or greater than a predetermined threshold value.

9. The control device according to any one of claims 1 to 8,

the control unit calculates a command value of the combustion speed for compensating for a deviation between a target value of a steam flow rate output from the waste incineration facility and the measured value of the steam flow rate, and corrects the combustion speed estimated by the combustion speed estimation unit based on the command value.

10. A waste incineration apparatus is provided with:

an incinerator for incinerating garbage;

a garbage feeding device for supplying garbage to the incinerator;

a blower for supplying combustion air to the incinerator;

a combustion air valve for controlling the flow rate of the combustion air supplied from the blower to the incinerator; and

the control device of any one of claims 1 to 9.

11. A control method, the control method comprising:

a step of acquiring a measurement value measured by a sensor provided in the waste incineration apparatus;

estimating a combustion speed in an incinerator of the waste incineration facility using the measurement value; and

and controlling the amount of garbage supplied or the flow rate of combustion air supplied to the incinerator based on the combustion speed.

12. A program that causes a computer to execute:

a step of acquiring a measurement value measured by a sensor provided in the waste incineration facility;

estimating a combustion speed in an incinerator of the refuse incineration facility using the measurement value; and