JP2000104912A - Waste incinerator and its control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrain the quantity of dioxins in an exhaust gas discharged from a chimney. SOLUTION: Dioxin concentrations of an outlet exhaust gas of a waste incineration system 1a and an outlet exhaust gas of an exhaust gas processing system 2a are respectively measured by means of dioxin measuring devices 3a (3b). In the dioxin measuring devices 3a (3b), an exhaust gas is ionized by an atmospheric pressure ion source, and the ionized material is analyzed by a mass spectrometry so that a concentration of dioxins is measured. Whether a main generation factor of dioxins is from the waste incineration system la or the exhaust gas processing system 2a is determined through the two positions dioxin concentrations by means of a control device 4a so as to cope with the main generation factor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refuse incineration facility for incinerating general waste and industrial waste and a control method thereof, and more particularly to a technique for suppressing the amount of dioxins in exhaust gas.

[0002]

2. Description of the Related Art As a waste incineration facility in consideration of dioxin control in a waste incinerator, a conventional incinerator is disclosed in, for example, Japanese Patent Laid-Open No. 4-2884.
No. 05 (hereinafter referred to as prior art 1) and Japanese Patent Application Laid-Open No. 9-2737.
There is one described in Japanese Patent Publication No. 30 (hereinafter referred to as prior art 2).

In the prior art 1, the CO concentration at the outlet of the incinerator or the outlet of the dust collector is detected to control the temperature of the exhaust gas at the inlet of the dust collector. Since the CO concentration has a correlation with the concentration of dioxins, the CO concentration is used as an alternative index of the dioxin concentration. Also, when the CO concentration is high, the exhaust gas temperature at the entrance of the dust collector is lowered to increase the dust collection efficiency,
When the CO concentration is low, the exhaust gas temperature is raised. In the downstream of the dust collector, it is necessary to raise the temperature due to restrictions of the denitration device. The reason for increasing the exhaust gas temperature at the entrance of the dust collector is to reduce heat loss before and after the dust collector.

Further, in the prior art 2, as in the prior art 1, the CO concentration is used as an alternative index, but the operation amount is the secondary air amount. Further, there is a feature that NOx is simultaneously reduced. Specifically, first, the relation between the secondary air amount, the CO concentration, the NOx concentration, and the furnace temperature is extracted from the operation data of the incinerator. Then, these relationships are expressed by fuzzy rules. According to this fuzzy rule, CO, NO
The secondary air amount is determined so as to keep both x low.

[0005] By the way, it is presumed that there are mainly the following two mechanisms for generating dioxins generated from refuse incineration facilities.

[0006] 1) It is generated in the process of burning refuse in an incinerator.

2) Exhaust gas is emitted from the incinerator and is generated in the process of reducing the temperature.

In the above 1), the net production amount is determined by the balance between the production amount of dioxin precursors such as chlorinated benzene and phenol chloride and the amount of decomposition of dioxin due to combustion. The amount of decomposition depends on the combustion state in the furnace. The reason why the CO concentration is used as a substitute for dioxin is that the CO concentration is an indicator of the combustion state. However, even though the CO concentration is an index of the decomposition rate of dioxin, it cannot be an index of the amount of the precursor produced. Therefore, when the CO concentration is the same, that is, even when the combustion state is the same, when the concentration of the precursor is different, the generation amount of dioxins is different. For this reason, the correlation between the CO concentration and the dioxin concentration may be broken. As a conventional technique for solving such a problem, there is one described in Japanese Patent Application Laid-Open No. H10-220727 (hereinafter referred to as Conventional Technique 3).

In the prior art 3, the concentrations of chlorobenzenes and / or chlorophenols are used as an alternative index of the dioxin concentration, and these concentrations are measured by a laser multiphoton ionization mass spectrometer. Further, the furnace oxygen concentration and the furnace temperature are also measured, and based on the information, the amount of waste supplied and / or the amount of combustion air is determined to be excessive or insufficient, and the amount of waste supplied and / or the amount of combustion air is adjusted. Therefore, the production amount of dioxins can be grasped more accurately than that of measuring the CO concentration and adjusting the waste supply amount and / or the combustion air amount, and the suppression effect is high.

[0010]

In order to estimate the amount of dioxins produced by measuring the concentration of chlorobenzenes or the like as in the above-mentioned prior art 3, it is necessary to use a trace amount of dioxins which is considered to be present in the exhaust gas. (1000 ng / Nm ³ or so) must be able to measure the chlorobenzenes and the like. That is, it is indispensable to provide a measuring means with high accuracy and substantially in real time. However, in the laser multiphoton ionization mass spectrometer, which is a measuring means described in the above-mentioned prior art 3, although monochlorobenzene, which is a monosubstituted chlorine, can be ionized to some extent, the number of chlorines substituted in the benzene nucleus is one. It is said that the sensitivity decreases from 1/7 to 1/10 every time it increases. That is, it can be said that trichlorobenzene, which is a tri-substituted product of chlorine, has only 1/100 sensitivity of monochlorobenzene. On the other hand, toxic dioxins are compounds in which four or more chlorine atoms have been substituted, and chlorobenzenes and the like, which are precursors thereof, have two or three or more chlorine atoms. Therefore, in the ionization method described in the related art 3, the ionization efficiency is reduced. That is, it is extremely difficult to measure a very small amount of the above-mentioned precursors (chlorobenzenes and / or chlorophenols) contained in the exhaust gas. As a result, the amount of dioxins produced cannot be accurately measured in real time. There is a problem that the effect of suppressing dioxins cannot be increased so much.

Further, in the above-mentioned prior art 3, dioxins generated in the process of burning refuse in an incinerator are dealt with only in the combustion furnace, and dioxins finally exhausted from the chimney are sufficiently suppressed. There is also a problem that it cannot be done.

Further, in the above-mentioned prior art 3, the operation target in which the concentration of dioxins decreases is determined by assuming the state of the furnace, based on the concentration of the dioxin precursor, the concentration of oxygen in the furnace, the temperature in the furnace, and the like. However, since the state of the flame in the furnace is not clearly understood, an appropriate operation target cannot be selected, and as a result, dioxins cannot be effectively suppressed.

[0013] Therefore, a first object of the present invention is to provide a refuse incineration plant capable of more accurately measuring the amount of dioxins produced and effectively controlling dioxins, and a control method therefor.

A second object of the present invention is to deal not only with dioxins in exhaust gas discharged from the combustion furnace, but also with dioxins exhausted from the combustion furnace. It is an object of the present invention to provide a refuse incineration facility capable of further suppressing the amount of waste and a control method thereof.

A third object of the present invention is to select an appropriate operation target according to the concentration of dioxins and to effectively control the amount of dioxins, and a method of controlling the same. It is to provide.

[0016]

A first refuse incinerator for achieving the first object is a refuse incinerator having a refuse incineration furnace and an operation end for operating the state of the refuse incineration furnace. Gas collecting means for collecting gas in the refuse incinerator or exhaust gas from the refuse incinerator; and dioxins and / or dioxins in the sample gas collected by the gas collecting means.
Or, a dioxin measuring device for measuring the amount of the dioxin precursor, and the amount of dioxins and / or the dioxin precursor measured by the dioxin measuring device, the operating amount of the operating end is determined, and the operating end is determined. Control means for outputting the manipulated variable, wherein the dioxin measuring device is ionized by the atmospheric pressure ionization means, and atmospheric pressure ionization means for ionizing the sample gas collected by the gas collection means under atmospheric pressure. Mass spectrometry means for mass spectrometry analysis of dioxins and / or dioxin precursors in the sample gas.

A second waste incineration plant for achieving the first object is the first waste incineration plant, wherein the dioxin measuring device is configured to determine a predetermined mass of the dioxin precursor and the dioxin The mass spectrometer further includes estimating means for estimating the mass of the dioxin from the mass of the dioxin precursor mass-analyzed by the mass spectrometric means using the relative relationship with the mass of the dioxin.

The third waste incinerator for achieving the first object may be any one of the first and second waste incinerators, wherein the dioxin measuring device is 1000
At the ng / Nm ³ level, the concentration of the dioxins and / or the dioxin precursors which are substituted with 2 chlorines or more is measured within an analysis time of 5 seconds and within a measurement error of ± 10%. It is assumed that.

A fourth waste incineration facility for achieving the first object is any one of the first to third waste incineration facilities, wherein the waste incinerator is provided with the control means controlled by the control means. As an operation end, a refuse supply speed adjusting means for adjusting a supply rate of refuse supplied to the refuse incinerator, a primary air amount adjusting means for adjusting a supply amount of primary air supplied to the refuse incinerator, A primary air temperature adjusting means for adjusting the temperature of the primary air, a secondary air amount adjusting means for adjusting a supply amount of the secondary air supplied downstream from a position to which the primary air is supplied; At least one of secondary air supply direction adjusting means for adjusting a direction in which air is supplied into the incinerator.

A first refuse incineration facility for achieving the second object is a refuse incinerator, an exhaust gas treatment system for treating exhaust gas from the refuse incinerator, and a passage through the exhaust gas treatment system. And a chimney for exhausting the exhaust gas, wherein a plurality of gas sampling means for sampling gas from the waste incinerator to the chimney at different locations, and a plurality of the gas sampling means. A plurality of dioxin measuring devices for measuring the amounts of dioxins and / or dioxin precursors in each sample gas sampled, and the amount of each dioxins and / or dioxin precursor measured by the plurality of dioxin measuring devices Therefore, the main generation factor of dioxins is determined by any one of a plurality of the gas sampling means (hereinafter referred to as a specific gas sampling means). ) Is determined to be due to a state on the upstream side, and the operation end of the equipment upstream of the specific gas sampling means is affected, and the amount of dioxins produced is affected according to the operation amount of the operation end. Control means for outputting an operation amount determined according to the amount of dioxins and / or dioxin precursors in the gas collected by the specific gas collection means. It is a feature.

A second refuse incineration plant for achieving the second object is the first refuse incineration plant for achieving the second object, wherein one of the plurality of gas sampling means is provided. The gas sampling means is an incinerator gas sampling means for sampling the gas in the refuse incinerator or the exhaust gas from the refuse incinerator before exhaust gas treatment to the exhaust gas treatment system. The means is a processing system gas sampling means for collecting the exhaust gas in the exhaust gas processing system, or the exhaust gas exhausted from the exhaust gas processing system, and one of the plurality of dioxin measurement devices is a dioxin measurement device. Is an incinerator dioxin measuring device for measuring the amount of dioxins and / or dioxin precursors in the sample gas collected by the incinerator gas sampling means, and one dioxin meter The apparatus is a processing system dioxin measuring device for measuring the amount of dioxins and / or dioxin precursors in the sample gas collected by the processing system gas collecting means, and the control means is configured to measure by the incinerator dioxin measuring device. From the amount of dioxins and / or dioxin precursors obtained, and the amount of dioxins and / or dioxin precursors measured by the treatment system dioxin measurement device, the main generation factor of dioxins is the waste incinerator. State or the state of the exhaust gas treatment system, and, among the refuse incinerator and the exhaust gas treatment system, with respect to the operating end of equipment having a major cause of generation of dioxins. The amount of dioxins and / or dioxin precursors measured by the dioxin measuring device of the facility. And outputs the manipulated variable, it is characterized in.

The third incineration facility for achieving the second object is a second incineration facility for achieving the second object, wherein the control means is provided in the incinerator. Refuse supply speed adjustment means for adjusting the supply rate of refuse supplied to the refuse incinerator, and primary air amount adjustment means for adjusting the supply amount of primary air supplied to the refuse incinerator, as the operating end to be controlled Primary air temperature adjusting means for adjusting the temperature of the primary air, secondary air amount adjusting means for adjusting the supply amount of secondary air supplied downstream from the position to which the primary air is supplied, At least one of secondary air supply direction adjusting means for adjusting a direction in which the secondary air is supplied into the incinerator; and the exhaust gas processing system is configured to remove dust in the exhaust gas. A dust device, and Exhaust gas temperature adjusting means for adjusting the temperature of the exhaust gas sent to the dust collecting device, and activated carbon supply amount adjusting means for blowing activated carbon into the exhaust gas sent to the dust collecting device as the operating end controlled by And at least one of the following.

[0023] A fourth waste incinerator for achieving the second object is a third waste incinerator for achieving the second object, wherein the fourth waste incinerator has an image capturing image of a flame in the waste incinerator. Means for controlling the amount of dioxins and / or dioxin precursors and various flame patterns in the refuse incinerator using a rule in which an operating end to be operated is determined. Determining an operation end according to the amount of dioxins and / or dioxin precursor measured by the furnace dioxin measurement device and the flame pattern imaged by the imaging means, and controlling the operation of the operation end; It is characterized by the following.

A first refuse incineration facility for achieving the third object is a refuse incineration facility having a refuse incinerator and a plurality of operating terminals for controlling the state of the refuse incineration furnace.
Gas sampling means for sampling gas in the refuse incinerator or exhaust gas from the refuse incinerator, and measuring the amount of dioxins and / or dioxin precursors in the sample gas collected by the gas sampling means. A dioxin measuring device, an imaging unit for imaging a flame in the refuse incinerator, and a plurality of operating terminals for a plurality of dioxins and / or dioxin precursors and various flame patterns in the refuse incinerator. An operation corresponding to the amount of dioxins and / or a dioxin precursor measured by the dioxin measuring device and the pattern of the flame imaged by the imaging means, using a rule in which an operation end to be operated is determined. And control means for determining the end and controlling the operation of the operation end.

Here, in the refuse incineration equipment for achieving the second object and the refuse incineration equipment for achieving the third object, the dioxin measuring device is collected by the gas collecting means. Atmospheric pressure ionization means for ionizing the sample gas under atmospheric pressure, and mass analysis means for performing mass analysis of dioxins and / or dioxin precursors in the sample gas ionized by the atmospheric pressure ionization means. Is preferred.

In each of the above refuse incinerators, when the refuse incinerator is a stalker furnace in which a stalker moves, the refuse incinerator is provided with the stoker as the operating end controlled by the control means. It is preferable that a stalker speed adjusting means for adjusting the moving speed is provided.

[0027] A method for controlling a refuse incinerator for achieving the first object is a method for controlling a refuse incinerator having a refuse incinerator and an operation end for controlling the state of the refuse incinerator, A gas sampling step for collecting gas in the incinerator or exhaust gas from the refuse incinerator, and dioxin measurement for measuring the amount of dioxins and / or dioxin precursors in the sample gas collected in the gas sampling step And a control step of determining an operation amount of the operation end according to the amount of dioxins and / or a dioxin precursor measured in the dioxin measurement step, and outputting the operation amount to the operation end. Wherein the dioxin measurement step ionizes the sample gas collected in the gas collection step by corona discharge under atmospheric pressure, and converts the sample gas in the ionized sample gas into To oxine compound and / or mass spectrometry of dioxin precursors, it is characterized in.

A method for controlling a refuse incineration plant for achieving the second object includes a refuse incinerator, an exhaust gas treatment system for treating exhaust gas from the refuse incinerator, and a method for passing through the exhaust gas treatment system. A stack for exhausting the exhaust gas, and a method for controlling a refuse incineration system, comprising: a gas sampling step of sampling gas from the refuse incinerator to the chimney at different locations; and a plurality of gas sampling steps. A dioxin measurement step of measuring the amount of dioxins and / or dioxin precursors in each sample gas collected at the location, and the amount of each dioxins and / or dioxin precursor measured in the dioxin measurement step, The main cause of dioxin emission is from any of multiple gas sampling points (hereinafter referred to as “specified gas sampling point”). Also determines whether the operation is due to the upstream state, and is the operation end of the equipment upstream of the specific gas sampling point, and affects the amount of dioxins produced according to the operation amount of the operation end. With respect to the operating end, dioxins and / or
Or a control step of outputting the manipulated variable obtained according to the amount of the dioxin precursor.

A method for controlling a refuse incineration plant for achieving the third object is a method for controlling a refuse incineration plant having a refuse incineration furnace and a plurality of operating terminals for controlling a state of the refuse incineration furnace. A gas sampling step of collecting gas in the refuse incinerator or exhaust gas from the refuse incinerator, and measuring the amount of dioxins and / or dioxin precursors in the sample gas collected in the gas collection step A dioxin measurement step, an imaging step of imaging a flame in the refuse incinerator, and various amounts of dioxins and / or dioxin precursors and various flame patterns in the refuse incinerator; Of these, using the rule in which the operating end to be operated is determined, the amount of dioxins and / or dioxin precursor measured in the dioxin measuring step and the previous Defining an operating end in accordance with the pattern of the flame by the imaging process, it is characterized in that and a control step of controlling the operation of said operating end.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Various embodiments of the refuse incineration equipment according to the present invention will be described below with reference to the drawings.

First, a first embodiment of a refuse incineration plant according to the present invention will be described with reference to FIGS. As shown in FIG. 1, the refuse incineration system of the present embodiment includes a refuse incineration system 1 having a refuse incinerator (stoker furnace) 10, an exhaust gas treatment system 2, a gas analyzer 3, a control device 4, a gas It has a sampling system 5 and a chimney 6.

In the refuse incinerator 10 of the refuse incineration system 1, the input refuse is dried and burned. As a result, the refuse becomes incineration ash and exhaust gas. The incinerated ash is carried out of the incinerator as needed, and the exhaust gas is sent to the exhaust gas treatment system 2. The refuse incinerator 10 is provided with various sensors for measuring the flow rate of the combustion gas, the temperature in the furnace, and the like. The measured values are sent to the combustion control device 4.

The exhaust gas treatment system 2 has a cooling tower 21, a dust collecting device 22, a gas heater 23, and a denitration device 24. In the exhaust gas treatment system 2, harmful substances such as fly ash and NOx contained in the exhaust gas are removed. Activated carbon may be blown before the dust collector 22 in order to increase the efficiency of removing harmful substances. The exhaust gas from which the harmful substances have been removed is released from the chimney 6 into the atmosphere. A gas collection system 5 is provided in the flue before the chimney 6, and the collected exhaust gas is sent to the gas analyzer 3.

The gas analyzer 3 includes various gas analyzers 31.
And a dioxin measuring device 32. The various gas analyzers 31 measure gas components such as HCL, SOx, CO, and O ₂ . The dioxin measuring device 32 measures the concentration of dioxins and / or the concentration of dioxin precursor online. These measured values are sent to the control device 4.

The controller 4 receives various state quantities such as temperature and pressure measured by the refuse incineration system 1 and measured values of various gas concentrations measured by the gas analyzer 3. Further, from the refuse incineration system 1, values of various operation amounts such as a stalking speed are input to the combustion control device 4. The control device 4 determines a stoker speed or the like which is an operation amount of the waste incineration system 1 based on the input information, and sends a control signal to the waste incineration system 1.

Next, the configuration of each part of this embodiment will be described.
This will be described in more detail. First, the waste incineration system 1 will be described in detail with reference to FIG. In the refuse incinerator 10, the refuse put in the refuse hopper 11 is carried on the stoker by the dust supply device 110. The stalker is a dry stoker 11
1, a combustion stoker 112 and a post-combustion stalker 113. The drying stoker 111 mainly evaporates the moisture of the input waste. In the combustion stoker 112,
Burn dry garbage. In the post-burning stalker 113, the refuse not completely burned by the burning stalker 112 is completely burned. The ash after combustion is once deposited in an ash pit (not shown) and then landfilled or melted.

Dry stoker 111, combustion stoker 11
The drying air, the combustion air, and the post-combustion air are blown into the second and post-combustion stokers 113 from below, respectively. Each air is sent to each of the stokers 111, 112, 113 by the primary air blower fan 131, and heat exchanges with a part of the combustion exhaust gas or steam (not shown) via the air heater 133 on the way. Temperature. The amount of air to the drying stoker 111, the burning stoker 112, and the post-burning stoker 113 is measured by the air flow meters 152a, 152b, and 152c. These air amounts are sent to the control device 4. The controller 4 compares the measured air amount and the air amount set value, and controls the driving amount of the primary air blower fan 131 and the distribution amount to each stoker so that the measured air amount becomes the air amount set value. Air dampers 121a and 121 for adjusting the pressure
b and 121c are controlled. This minor control system is not shown. In addition, each stoker 111, 1
The temperature of the air sent into the tubes 12, 113 is measured by the air temperature sensors 153a, 153b, 153c. These air temperatures are also sent to the control device 4. The controller 4 compares the measured air temperature with the air temperature set value, and is controlled by a minor control system (not shown) so that the measured air temperature becomes the air temperature set value. The operation end of this minor control system is provided with temperature control dampers 124aa, 12a provided on a path for directly guiding air from the primary air blower fan 131 to each of the stokers 111, 112, 113 without passing through the air heater 133.
4ba, 124ca, and temperature control dampers 124ab, 12 provided on a path for guiding the air heated by the air heater 133 to the stokers 111, 112, 113.
4bb and 12cb. Each stalker 111, 11
2 and 113 are supplied to a temperature control damper 12.
The temperature is adjusted by adjusting the distribution ratio between the air that has passed through 4aa, 124ba, and 124ca and the high-temperature air that has passed through dampers 124ab, 124bb, and 12cb for temperature adjustment.

Further, secondary air blowing nozzles 134a and 134b are attached to the upper part of the stalker.
By the secondary air supplied from the secondary air blowing nozzles 134a and 134b, a gas containing a large amount of unburned components generated on the drying stalker 111 and a high-temperature gas generated on the combustion stalker 112 are mixed. Further, oxygen in the secondary air is supplied to these gases. As a result, most combustible substances are burned. The blowing amount (blowing speed) of the secondary air is adjusted by the driving amount of the secondary air blowing fan 132 and the opening degree of the secondary air damper 129.
The driving amount of the secondary air blowing fan 132 and the opening degree of the secondary air damper 129 are all determined by the combustion control device 4.
Is controlled by The combustion exhaust gas has a high temperature of 800 to 900 ° C. in the furnace outlet path 12. The temperature of the combustion exhaust gas and the temperature of the furnace wall are respectively measured by the furnace temperature sensor 15.
1a and 151b. In order to protect the furnace wall from high-temperature combustion gas, the gas temperature may be reduced by spraying water with a gas cooling device (not shown) so that the combustion exhaust gas temperature or the furnace wall temperature becomes equal to or lower than a reference value. Those having a boiler at the outlet of the incinerator are subjected to heat exchange in this boiler, and the temperature of the combustion exhaust gas is reduced to about 500 ° C. The combustion exhaust gas discharged from the refuse incinerator 10 is sent to the exhaust gas treatment system 2.

In this embodiment, as described above, from the combustion control device 4, the dust supply device 110 and each of the stalker 11
Control signals are sent to the moving mechanisms 1 to 113 (stoker speed adjusting means), the air damper 121, the temperature adjusting air damper 124, the secondary air damper 129, the fan 131, and the secondary air fan 132. The drive amount and the like are adjusted. With this control signal, a minor control system (not shown) operates to control the dust supply speed, each stalker speed, each air temperature, and each air flow rate.

Next, the exhaust gas treatment system 2 will be described in detail. The exhaust gas treatment system 2 includes, as described above, the cooling tower 2
1, dust collecting device 22, gas heater 23, denitration catalyst device 24
have. About 500 discharged from refuse incinerator 10
Exhaust gas of about ° C. (exhaust gas passing through the boiler) is first cooled to about 250 ° C. to 200 ° C. in the cooling tower 21 and then guided to the dust collector 22. The reason for lowering the temperature of the exhaust gas before the dust collector 22 is to reduce dioxins. The reason why dioxins can be reduced by lowering the exhaust gas temperature will be described later. Dust collector 2
In 2, the fly ash in the exhaust gas is removed. The exhaust gas from which the fly ash has been removed is guided to the gas heater 23 and heated to about 300 ° C. This is for maintaining the denitration effect of the subsequent denitration device 24 and for preventing the exhaust gas discharged from the chimney 6 from white smoke. The exhaust gas whose temperature has been raised to about 300 ° C. is guided to a denitration device 24, from which NOx in the exhaust gas is removed, and discharged to the atmosphere through a chimney 6.

Next, the generation mechanism of dioxins in the waste incineration system 1 and the exhaust gas treatment system 2 will be described.
Dioxins are the numbers 1 to 9 of the two compounds shown in (Chemical Formula 1) and (Chemical Formula 2); It is a general term for a group of compounds in which hydrogen at the indicated position is replaced by chlorine (Cl). Applicable compounds: 75 PCDDs, 135 PCDFs
There are species.

[0042]

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[0043]

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Among the PCDDs, dioxin (2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-) in which four Cls have been substituted at positions 2,3,7,8 TCDD)) is the most toxic. Of the dioxins with 4 or more chlorine substitutions, 7 for PCDDs and 10 for PCDFs
Certain compounds are toxic. The toxicity of these compounds is 2,
It is defined as the relative value (toxic equivalent coefficient) for the toxicity of 3,7,8-TCDD. The value obtained by multiplying the concentration of each compound in the sample collected from the incineration plant by this coefficient is defined as the equivalent toxic dose (TEQ) and is used as an index of the toxicity of the sample.

It is presumed that two routes exist for the production of dioxins in the waste incineration process.

The first route is a route in which dioxins are generated from unburned organic chlorine compounds in the refuse incinerator 10. For example, as shown in (Chemical formula 3), this is a pathway in which two trichlorophenols are condensed to produce 2,3,7,8-TCDD. In the present invention, this is referred to as a production route from the precursor. The second route is a route in which dioxins are generated by chlorination of unburned organic compounds in a low-temperature part such as the exhaust gas treatment system 2. For example, as shown in (Chem. 4), this is a route in which dibenzofuran is chlorinated to generate polychlorinated dibenzofurans (PCDFs). In the present invention, this is referred to as a chlorination regeneration route.

[0047]

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[0048]

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Hereinafter, each generation path will be described in more detail. The first route, ie, the reaction of (Chem. 3), has been reported in the past (Yuo Onodera, Environmental Technology 18
According to Vol. 3, No. 3, p. 153 (1989)), the reaction proceeds at a temperature around 500 ° C. The boiling points of chlorophenols, which are precursors of dioxins, are 174 ° C for monochloride and 309 ° C for pentachloride.
The boiling points of chlorobenzenes, which are also precursors of dioxins, are 132 ° C. for monochloride and 309 ° C. for hexachloride. Accordingly, the precursor of dioxins contained in the waste is vaporized in the drying stage of the stoker furnace 10 and diffuses into the combustion zone, for example, when the temperature reaches 500 ° C. or more, the chemical formula is shown in (Chem. 3). Such reactions occur to produce dioxins. Since this reaction is performed in parallel with the combustion reaction, a part of the reaction is decomposed and discharged, and discharged as carbon dioxide, hydrogen chloride, and water vapor, and the remainder is discharged as dioxins as it is.

As shown in FIG. 3, when the combustion rate in the combustion furnace 10 is improved, the amount of decomposition of dioxins by combustion increases, and the net amount of dioxins produced decreases. Combustion furnace 10
For example, if the temperature condition of about 500 ° C. is maintained in the boiler even after exiting from the boiler, the generation and decomposition reaction of dioxins continue to proceed. Under this temperature condition, the combustion rate decreases, so the amount of decomposition of dioxins generated in the boiler decreases, and as a result, the net amount of dioxins generated is smaller than the net amount of dioxins generated in the combustion furnace 10. To increase.

On the other hand, the chlorination reaction of the second route, ie, chemical formula 4, proceeds by the action of a catalyst component such as copper chloride contained in fly ash. This chlorination reaction occurs downstream of the cooling tower 21 of the exhaust gas treatment system 2 because the reaction temperature is low. Dioxins are generated in a state of being adsorbed on particles such as fly ash. Therefore, dioxins generated in the second route are generated downstream of the cooling tower 21 of the exhaust gas treatment system 2, that is, per dirt collector 22. As shown in FIG. 3, most of the dioxins generated in the second route are removed by the dust collecting device 22 along with the removal of dust such as fly ash. In addition, a part of the gaseous dioxins generated in the first path is also cooled by the cooling tower 21 and, as a result, is adsorbed by particles such as fly ash, and is collected by the dust collecting device 22.
As a result, dust and other dust such as fly ash are removed, and the other part is decomposed by the denitration catalyst.

Thus, gaseous dioxins are:
As the temperature is lowered, specifically, 250 ° C. to 200 ° C.
When the temperature is lowered to about ° C., the particles adhere to the particles and can be removed by the dust collecting device 22.

Next, the gas analyzer 3 will be described.
As described above with reference to FIG. 1, the gas analyzer 3 includes various gas analyzers 31 and a dioxin measuring device 32. The sample gas taken into the gas analyzer 3 is taken from a gas sampling system 5 installed between the exhaust gas treatment system 2 and the chimney 6. Therefore, most of the dust in the sample gas is removed by the dust collecting device 22. In the various gas analyzers 33, after removing water from the sample gas by a drain pot, a trace amount of dust is removed by a glass filter. Then, gas components such as HCL, SOx, CO, and O ₂ are measured from the sample gas from which dust and moisture have been removed. In the present embodiment, HCL, SOx,
For measurement of gas components such as CO and O ₂ , a commonly used continuous analyzer is used. .

In the dioxin measuring device 32, it is necessary to send the sample gas to the monitor section stably and at a constant flow rate. In addition, it is necessary to prevent the substance to be analyzed from being adsorbed or condensed on the way and lost. Therefore, the pretreatment is different from that of the various gas analyzers 33.

As shown in FIG. 4, the dioxin measuring device 32 includes a gas pre-processing section 3 for transporting and pre-treating a sample gas.
21 and a monitor unit 322 for detecting a substance to be measured from the sample gas, and a data processing unit 323 for processing data detected and obtained.

The gas pretreatment section 321 is a quartz or glass filter 3 for removing solid impurities and fly ash in the sample gas.
21a, the flow path switching valve 321b, and the monitor 322
A heating pipe 321c for heating the sample gas to be sent to the pressure control needle valve 321d, an exhaust pump 321e for exhausting the sample gas detected by the monitor unit 322, an exhaust gas pipe 321f, and an exhaust gas probe 321g. And a standard gas generator 321h.
Filter 321a of gas pretreatment section 321, flow path switching valve 321b, heating pipe 321c, pressure regulating needle valve 3
21d is heated to about 100 ° C to 200 ° C by a heater. The switching valve 321b is connected to the monitor 3
The operation is performed when switching between the case of sending to the monitor unit 322 and the case of sending the standard gas from the standard gas generator 321h to the monitor unit 322. The standard gas from the standard gas generator 321h is used when calibrating the monitor unit 322.

The monitor section 322 is provided with an atmospheric pressure chemical ion source 322a for selectively and highly efficiently ionizing a substance to be analyzed in the supplied material gas, and an intermediate pressure chamber from the atmospheric pressure chemical ion source 322a. It has a mass analyzer 322b for mass-analyzing the ionized gas sent thereto, and a vacuum pump 322c for sending the gas in the mass analyzer 322b to an exhaust gas pipe 321f of the gas pretreatment unit 321.

The data processing unit 323 includes a mass spectrometer 322
b, an amplifier 322a for amplifying the signal from
A calculator 323b for estimating the total concentration of the precursors or the concentration of dioxins based on the signal from the mass spectrometry unit 322b amplified in 2a.

Next, the flow of gas in the dioxin measuring device 32 will be described. The gas that has passed through the flue and the gas sampling system 5 before the chimney 6 passes through the filter 321a of the gas pretreatment unit 321 to remove solid impurities and fly ash in the sample gas. The filter 321a may be a two-stage or three-stage filter depending on the amount of fly ash at the gas sampling location. Dioxins and organic chlorine compounds are adsorbed in the fly ash removed by the filter 321a. Therefore, in order to desorb these adsorbed components, the filter 321a is heated to 100 to 500C, preferably 150 to 200C. Filter 32
The sample gas passing through 1a is sent to an atmospheric pressure chemical ion source 322a via a switching valve 321b. Here, dioxins and organic chlorine compounds are ionized by corona discharge. Atmospheric pressure chemical ion source 322a
A portion of the sample gas that has passed through is drawn by an exhaust pump 321e, and a needle valve 321d and an exhaust gas pipe 321 are drawn.
f, The gas is exhausted to the flue via the exhaust gas probe 321g. The needle valve 321d regulates the gas flow,
The pressure inside the ion source 322a is made constant. Note that a pressure regulator, a mass flow controller, or the like may be used instead of the needle valve 321d. Atmospheric pressure chemical ion source 322a
The remainder of the ionized sample gas after mass spectrometry is subjected to mass analysis in the mass spectrometer 322b, then pulled by the vacuum pump 322c, exhaust gas piping 321f, and the exhaust gas probe 321.
Exhaust to the flue via g. Each piping system and ion source 322
a has a confidential structure to prevent leakage to the outside and invasion of the outside atmosphere.

The monitor section 322 ionizes the substance to be measured and measures its mass. The ionization method includes a positive ionization mode and a negative ionization mode. The method used in the present embodiment is a negative ionization mode. Atmospheric pressure ionization in the negative ionization mode has high sensitivity to selectively ionize organochlorine compounds in the presence of many interfering substances,
It is a highly selective ionization method. In particular, since this atmospheric pressure ionization utilizes corona discharge, the ionization probability is determined by the electron affinity of the electron species, and the ionization probability tends to increase as the chlorine number increases. Therefore, the sensitivity to toxic dioxins having 4 or more chlorine atoms and chlorobenzenes having 2 or 3 or more chlorine atoms as a precursor thereof increases, and the amount of dioxins and precursors produced can be accurately determined. Can be measured. In addition, according to this negative ionization, many organic compounds such as dioxin and its precursor are ionized together. In atmospheric pressure ionization, if the mass of the generated negative ions is known, the analysis target can be further narrowed down. The mass analyzer 322b is used for selecting the generated ions.

For the ions introduced into the mass spectrometer 322b, the ion intensity for each mass number (molecular weight / charge (m / e)), that is, the mass spectrum is measured. The measurement of the mass spectrum is usually completed in one second or less.

Chlorobenzenes, which are precursors of dioxins, capture one electron and become a molecular ion M￣ (where neutral molecules are M and negative ions are M￣). In addition, chlorophenols have a phenoxy group (—OH
Group) and loses one proton to become a pseudo-molecular ion (MH)}. Dioxins are not only molecular ion M￣ but also (M-
Cl) {, (M-Cl + O)} or dissociated 1,2
It becomes an orthoquinone-type fragment ion and the like. The mass spectrometry unit 322b can measure with high selectivity and high sensitivity by selectively detecting these characteristic peaks of ion intensity. Specifically, this dioxin measuring device 32
At the level of 1000 ng / Nm ³ , the concentration of dioxins or their precursors having a dichloride substitution or higher can be measured within a measurement error of ± 10% and within an analysis time of 5 seconds.

In the data processing unit 323, the mass analysis unit 32
The signal indicating the analysis result from 2 is amplified by the amplifier 323a, and is subjected to arithmetic processing by the arithmetic unit (estimating means) 323b to estimate the concentration of dioxins. Arithmetic unit 323b
In order to estimate the dioxin concentration from the concentrations of chlorobenzenes and chlorophenols, the correlation between chlorobenzenes and chlorophenols and dioxins, which is obtained in advance, is used.

Here, the correlation between dioxins and chlorophenols will be described in detail. However,
The dioxins described herein are generated by the first route.

The highest temperature reached in the drying stalker 111 is 300 ° C. to 400 ° C. This temperature is higher than the boiling point of chlorophenols, and almost all chlorophenols contained in the waste gasify. Therefore, the concentration of chlorophenols in the gas phase is determined by the amount of chlorophenols contained in the waste and the total gas amount. Here, assuming that the amount of waste supplied is F (ton / h), the amount of chlorophenols contained in waste is P (ppm), and the amount of combustion gas is Q (Nm3 / h), The concentration CP (ppm) in the phase can be expressed as the following (Equation 1). (197.5) in (Equation 1) is the molecular weight of chlorophenols.

CP = (F * P / 197.5 * 0.0224 * 298/273) / Q (Equation 1) The concentration of chlorophenols according to the temperature rise in the course of the input waste moving on the drying stage Is going to rise. That is, at the temperature T (° C), the vapor pressure VP (mmHg)
Then, the concentration of chlorophenols in the gas phase CPT (p
pm) can be expressed as (Equation 2).

CPT = CP * VP / 760 (Equation 2) The chlorophenols released into the gas phase cause a dioxin-forming reaction shown in (Chemical Formula 1) simultaneously,
Causes a combustion reaction. However, comparing both reaction rates, the combustion reaction is much faster. Therefore, it can be assumed that dioxins are produced sequentially from unburned unburned chlorophenols. That is, assuming that the burning rate of chlorophenols is ηcp (%), the concentration of unburned chlorophenols ([chlorophenol] ₀ )
Can be expressed as (Equation 3).

[Chlorophenol] ₀ = CP * (100−ηcp) / 100 (Equation 3) In the process of producing dioxins from chlorophenols, two molecules of chlorophenols condense with each other as shown in (Chem. 3). To produce dioxins. Therefore,
The generation rate of dioxins is expressed as (Equation 4). In (Equation 4), [chlorophenol] is the concentration of chlorophenols to be measured.

−2 * d [chlorophenol] / dt = d [dioxins] / dt = k [chlorophenol] (Equation 4) By solving (Equation 4), the concentration of dioxins becomes the production rate constant k Is represented by (Equation 5).

[Dioxins] = 1/2 {[chlorophenol] ₀ * (1-exp (−k * t))} (Equation 5) Here, the concentration of unburned chlorophenol [chlorophenol] ₀ The measured concentration of chlorophenols [chlorophenol] is almost the same. Therefore, (Equation 5) can be expressed as (Equation 6).

[Dioxins] = 1/2 {[chlorophenol] * (1-exp (−k * t))} (Equation 6) As described above, according to (Equation 6), chlorophenols From the measured concentration, the concentration of dioxins can be estimated. By the way, the generation rate constant k in (Equation 6) varies depending on the atmosphere such as temperature. For this reason, it is desirable to determine the formation rate constant k by measuring the concentration of chlorobenzene and chlorophenols and simultaneously measuring the dioxin concentration by an official method. In addition, since the correlation may vary depending on the shape of the refuse incinerator, it is desirable to obtain correlation data for each furnace in order to estimate the dioxin concentration with higher accuracy. In the above description, the correlation between the concentration of dioxins and the concentration of chlorophenols was determined from the equation. However, both concentrations may be measured, and the correlation between the two may be determined from the result.

In the same manner as described above, the concentration of dioxins can be estimated from the measured concentration of chlorobenzenes. As described above, when the concentration of chlorobenzenes and chlorophenols, that is, the precursors, increases, the concentration of dioxins also increases in a certain relationship. Therefore, the arithmetic unit 323b of the present embodiment uses the chlorobenzenes and chlorophenols. Is sent to the control device 4.

Instead of sending the precursor concentration, the dioxin concentration estimated from the measured concentration of chlorophenols and the dioxin concentration estimated from the measured concentration of chlorobenzene are added, and this is added to the dioxin concentration. The estimated value may be sent to the control device 4 as the concentration of the class. In this case, the actually measured dioxin concentration may be sent to the control device 4, but here, in order to calibrate the dioxin concentration estimated from the precursor concentration, the measured dioxin concentration is calculated. Good to use. This is because, because the concentration of dioxins in the sample gas is low, it takes much longer to measure than the measurement of the precursor, and the measured concentration of dioxins is not suitable for controlling in real time. It is.

Next, the combustion control device 4 will be described with reference to FIG. The control device 4 includes a data recording device 41, an inference engine 42, and a rule base 43.

The following recording values or values measured by the waste incineration system 1 are input to the data recording device 41.

1) Various state quantities such as temperature, pressure, air flow rate, etc. measured by the refuse incineration system 2) Dioxin and / or dioxin precursor concentration measured by the dioxin measuring device 32 3) Various gas analyzers HCL, SO measured at 31
concentration of x, CO, O _2, etc. 4) Various manipulated variables such as each stalker speed and air damper opening in the refuse incineration system 1 In this embodiment, the data of the above 1) to 4) are recorded at 5 second intervals. 41 are sequentially input. The value input to the data recording device 41 is stored in the data recording device 41 and, at the same time, passed to the inference engine 42. The inference engine 42 uses the input data and the rules stored in the rule base 43 to output a command to change the stoker speed, the air damper opening, etc., which are the operation amounts of the waste incineration system 1.

Here, the rules used when the estimation engine 42 determines various operation amounts will be described. This rule is based on the findings obtained by the inventors after examining factors that influence the concentration of the dioxin precursor. The findings obtained by the inventors are as follows.

Observation: The concentration of the dioxin precursor at the outlet of the refuse incinerator 10 increases in the following cases.

1) The amount of the dioxin precursor generated from the drying stoker 111 is large. 2) The gas containing a large amount of unburned components generated on the drying stoker 111 by the secondary air and the high-temperature gas generated on the combustion stoker 112. Low mixing speed with gas.

3) The combustion condition in the upper part of the combustion stoker is poor (low flame temperature, insufficient combustion air).

Assuming that the combustion state (flame temperature) at the upper part of the stalker in the above 3) and the mixing speed in the above 2) are fixed to a constant state, the amount of the dioxin precursor that can be decomposed in that state is fixed. Is determined. Therefore, if the amount of the precursor is equal to or less than the decomposition amount, most of the precursor is decomposed by the furnace outlet regardless of the amount of the generated precursor. However, when the decomposition amount is exceeded, the precursor is discharged from the furnace outlet in an amount exceeding the decomposition amount.

A rule based on the above findings will be described with reference to FIG. It should be noted that the rule shown in the figure is used to determine the operation amount when the concentration of the dioxin precursor increases because the operation amount does not need to be changed when the measured amount of the dioxin precursor is low. Part of the rules.

The rules are IF THEN format rules. In this rule, the magnitude of the state quantity such as the furnace temperature is set to 5 (for example, (high, slightly high, medium, slightly low, low)).
We evaluate at stage.

Rule 1 is a rule when the furnace temperature is high and the O ₂ concentration is medium, but the concentration of the dioxin precursor is high. In this case, it can be estimated that the combustion state is good because the furnace temperature is high. Therefore, it is determined that the reason why the concentration of the dioxin precursor has increased is that the mixing speed of the combustion gas by the secondary air is low, and a command to increase the flow rate of the secondary air is issued to the secondary air blowing fans 132 and Put it out to the next air damper 129. In this case, if there is a secondary air supply direction adjusting means capable of adjusting the direction of the secondary air blowing nozzle 134a, a command to change the supply direction may be issued to the direction adjusting means so as to increase the gas mixing efficiency.

Rule 2 is a rule when the furnace temperature is slightly high and the O ₂ concentration is slightly low. In this case, since there is a high possibility that the amount of combustion air is slightly insufficient, a command to increase the amount of combustion air is issued to the primary air blower fan 131 and the air dampers 121a, 121b, 121c.

[0086] Rule 3 is the furnace temperature is moderate, O ₂ concentration is rules for slightly lower. Also in this case, the amount of combustion air may be insufficient for the amount of waste,
Increasing the amount of combustion air that is lower than the furnace temperature may decrease the furnace temperature. Therefore, in this case, a command is issued to reduce the speed of the drying stalker and the speed of the combustion stalker in order to reduce the amount of waste transferred.

As described above, in any of the rules, the operation amount commanded from the control device 4 to each operation terminal is determined in accordance with the concentration of the precursor.

In this embodiment, rules are created in which the magnitude of the state quantity is evaluated in five steps. However, these rules may be converted to fuzzy rules to construct a control algorithm.

As described above, in this embodiment, since the exhaust gas is ionized by the corona discharge under the atmospheric pressure by the atmospheric pressure ionization source 322b, the ionization probability is determined by the electron affinity of the electron species, and the chlorine number is reduced. The higher the number, the higher the sensitivity. In other words, the sensitivity to toxic dioxins having 4 or more chlorine atoms or chlorobenzenes having 2 or 3 or more chlorine atoms as a precursor thereof increases, and the dioxins and The amount of the precursor generated can be measured accurately. Therefore, in the present embodiment, dioxin suppression control is performed based on the accurately measured amounts of dioxins and their precursors, so that dioxins can be effectively suppressed.

Next, a second embodiment of the refuse incineration plant according to the present invention will be described with reference to FIGS.

As shown in FIG. 1, the refuse incineration system of this embodiment includes a refuse incineration system 1a having a refuse incinerator (stoker furnace) 10, an exhaust gas treatment system 2a, a gas analyzer 3,
3a, a combustion control device 4a, a gas sampling system 5, 5a,
And a chimney 6.

As shown in FIG. 8, the waste incineration system 1a includes two imaging cameras 16 for imaging the inside of the waste incinerator 10.
It is the same as the first embodiment except that a and 16b are provided. Of the two imaging cameras 16a and 16b, one imaging camera 16a is installed on the furnace wall behind the refuse incinerator 10 (on the side of the post-combustion stalker), and faces in the direction in which the refuse moves. , The combustion state is imaged. Another one of the imaging cameras 16b is installed on a side wall of the refuse incinerator 10 and captures an image of a combustion state in a direction perpendicular to a garbage transfer direction. These imaging cameras 16a and 16b use wide-angle lenses because it is necessary to image the combustion state of a wide range of the drying stalker 111, the burning stalker 112, and the post-burning stalker 113. When the image quality is deteriorated by using the wide-angle lens, it is preferable to share the imaging range by using a large number of imaging cameras.

As shown in FIG. 7, the exhaust gas treatment system 2a
In the exhaust gas treatment system 2 of the first embodiment, a temperature control device for controlling the temperature of the exhaust gas passing through the cooling tower 21, and activated carbon blowing in which activated carbon is blown while the exhaust gas enters the dust collector 22. And an embedded facility 25. The temperature control equipment includes a water supply source 211 that supplies water to the cooling tower 21.
And a water supply amount adjustment valve 212 for adjusting the amount of water supplied from the water supply source 211 to the cooling tower 21. The activated carbon blowing equipment 25 has an activated carbon blowing source 251 for blowing activated carbon into exhaust gas, and an activated carbon amount control valve 252 for adjusting the amount of activated carbon blown into the exhaust gas from the activated carbon blowing source 251. ing. The opening degree of each of the water supply amount control valve 211 and the activated carbon amount control valve 252 is controlled by the control device 4.
It is controlled by an instruction from a.

One of the two gas sampling systems 5, 5a is provided in the flue between the exhaust gas treatment system 2a and the chimney 6, as in the first embodiment. Of the garbage incinerator 10
Is provided on the upper wall. The gas analyzers 3 and 3a are connected to the gas sampling systems 5 and 5a, respectively. The processing system gas analyzer 3 for measuring the exhaust gas collected between the exhaust gas processing system 2a and the chimney 6 is exactly the same as the gas analyzer 3 of the first embodiment. Further, the incinerator gas analyzer 3a for measuring the exhaust gas collected from the upper part of the drying stalker 111 is basically the same as the gas analyzer 3 of the first embodiment. Since a large amount of exhaust gas is measured, a heat-resistant and high-performance ceramic filter is used as a filter of the gas pretreatment unit, and the heating temperature of the piping system is set higher than in the first embodiment. When dust is removed by the ceramic filter, catalytic components such as copper chloride are also removed. Therefore, even if the temperature of the collected gas becomes low, dioxins are not generated by chlorination regeneration. Therefore, the concentration of the dioxins and / or the dioxin precursor in the gas collected from the upper portion of the drying stalker 111 can be accurately measured by the incinerator gas analyzer 3a.

As shown in FIG. 9, the control device 4a includes an image processor 45a for performing image processing of image data from the imaging cameras 16 and 16a, a data recording device 41a for recording various data, and any operation terminal. And the rule base 43a in which a rule for controlling the control is stored.
And an inference engine 42a that controls the operation end in accordance with the rules stored in 3a.

As shown in FIG. 10, the image processor 45a divides the image from the imaging cameras 16 and 16a into a plurality of regions, obtains the average luminance for each region, and determines that the average luminance is smaller than a specific value. The flame pattern is grasped assuming that a flame exists in a large area. This flame pattern is recorded in the data recording device 41a. As shown in FIG. 9, the data recording device 41a also records the state quantities and operation amounts of the waste incineration system 1a and the measurement data of the gas measuring devices 3 and 3a, as in the first embodiment. .

The inference engine 42a outputs a command to change the manipulated variables of the refuse incineration system 1a and the exhaust gas treatment system 2a using the input data and the rules stored in the rule base 43a. Also in the second embodiment, the inference engine 42a is a control algorithm based on the IF THEN rule. However, since more data is acquired than in the first embodiment, the inference engine 42a uses the rules 1 to 3 in the first embodiment.
In addition, as shown in FIG. 11, using rules 4 to 7,
Outputs a command to change each manipulated variable.

Rule 4 is a rule in the case where the concentration of the dioxin precursor above the drying stalker 111 is high and the temperature in the furnace is slightly high. In this case, it is considered that the generation amount of the dioxin precursor increased due to the change in the waste quality and the like. Here, the combustion state in the furnace is relatively good,
It is difficult to further improve the combustion state. Therefore, by outputting a command to lower the dry air temperature to the dampers 124aa and 124ba for temperature adjustment, and outputting a command to reduce the amount of dry air to the primary air blowing fan 131 and the air damper 121a, The amount of the dioxin precursor generated from the drying stalker 111 can be suppressed.

Rule 5 is a rule in the case where the concentration of the dioxin precursor at the furnace outlet is medium, but the concentration of the dioxin precursor at the entrance of the chimney is high. in this case,
As described above with reference to FIG. 3, it is considered that the cause is that the exhaust gas is emitted from the refuse incineration system 1a and the amount of dioxins newly generated in the exhaust gas treatment system 2a is increased. Therefore, in order to increase the amount of dioxins adsorbed on the particles, a change command is output to the water supply amount control valve 21 of the temperature control equipment to lower the outlet gas temperature of the temperature reduction tower 21 and to activate the activated carbon. Activated carbon control valve 252
In response to this, a change command is output to increase the amount of activated carbon blown.

[0100] Rule 6 shows that the dry stalker 11 shown in FIG. 10B is different from the ideal flame pattern shown in FIG.
1 becomes brighter and the drying stalker 111
This is a rule in the case where the concentration of the dioxin precursor in the upper part of is slightly higher. This is because the amount of water in the garbage is small, the garbage burns at the rear of the drying stalker 111 before the garbage reaches the combustion stalker 112, and the radiant heat promotes the drying of the garbage, thereby increasing the amount of dioxin precursor generated. it is conceivable that. Therefore, a change command to increase the speed is output to the drying stalker moving mechanism, and a change command to lower the dry air temperature is output to the temperature adjustment dampers 124aa and 124ba.

The rule 7 is different from that of the ideal flame pattern shown in FIG.
This is a rule in the case where the brightness of the rear part becomes high and the concentration of the dioxin precursor on the upper part of the drying stalker 111 is slightly high. This is the case where the amount of moisture in the garbage is large, the garbage is not sufficiently dried even after passing through the drying stalker 111, and the garbage is burning from the middle part of the combustion stalker 112 to the post-combustion stalker 113.
Accordingly, a change command is output to the drying stoker moving mechanism and the combustion stoker moving mechanism to reduce the speed, and the temperature adjusting dampers 124aa and 124b are output.
In response to a, a change command for increasing the dry air temperature is output.

As described above, in this embodiment, as in the first embodiment, the gas measuring devices 3a, 3b
Since the gas is ionized by the atmospheric pressure ionization source and the gas is subjected to mass spectrometry, the amount of dioxins and their precursors generated can be accurately measured, and dioxins can be effectively suppressed.

In this embodiment, the amount of dioxins or their precursors at the outlet of the refuse incinerator 10 is measured, and the amount of dioxins or their precursors at the outlet of the exhaust gas treatment system 2a is also measured. It is determined whether the main cause of the generation of dioxins is on the refuse incinerator 10 side or the exhaust gas treatment system 2a side, and the cause of the generation is dealt with. Therefore, dioxin exhausted from the chimney 6 is finally discharged. The amount of the class can be suppressed effectively.

Further, in this embodiment, the flame in the incinerator 10 is imaged, and an appropriate operation target is selected according to the imaged flame pattern and the concentration of dioxins. It can be suppressed effectively.

[0105]

According to the invention of the present application, in the gas measuring device, the exhaust gas is ionized by the atmospheric pressure ionization source 322b by corona discharge under the atmospheric pressure, so that the gas is ionized by the atmospheric pressure ionization source. Since it is subjected to mass spectrometry, the amount of dioxins and their precursors produced can be accurately measured. For this reason, in the present invention, dioxin suppression control is performed based on accurately measured amounts of dioxins and their precursors, so that dioxins can be effectively suppressed.

In another invention of the present application, the amount of dioxins or their precursors in the gas collected at a plurality of locations is measured, and it is determined where the main cause of the generation of dioxins is. Since the cause of occurrence is dealt with, the amount of dioxins finally exhausted from the chimney 6 can be effectively suppressed.

In still another invention of the present application, a flame in an incinerator is imaged, and an appropriate operation target is selected according to the imaged flame pattern and the concentration of dioxins.
The amount of dioxins can be effectively suppressed.

[Brief description of the drawings]

FIG. 1 is a system diagram of a waste incineration plant as a first embodiment according to the present invention.

FIG. 2 is a configuration diagram showing a schematic configuration of a refuse incineration system as a first embodiment according to the present invention.

FIG. 3 is an explanatory diagram showing the generation balance of dioxins for each temperature range.

FIG. 4 is a configuration diagram showing a schematic configuration of a dioxin measuring device as a first embodiment according to the present invention.

FIG. 5 is a functional block diagram showing a functional configuration of a control device as a first embodiment according to the present invention.

FIG. 6 is an explanatory diagram showing a rule for selecting an operation end as the first embodiment according to the present invention.

FIG. 7 is a system diagram of a refuse incineration plant as a second embodiment according to the present invention.

FIG. 8 is a configuration diagram showing a schematic configuration of a refuse incineration system as a second embodiment according to the present invention.

FIG. 9 is a functional block diagram showing a functional configuration of a control device as a second embodiment according to the present invention.

FIG. 10 is an explanatory diagram showing a flame pattern in a refuse incinerator as a second embodiment according to the present invention.

FIG. 11 is an explanatory diagram showing a rule for selecting an operation end as a second embodiment according to the present invention.

[Explanation of symbols]

1, 1a: refuse incineration system, 2, 2a: exhaust gas treatment system, 3,
3a: gas analyzer, 4, 4a: combustion controller, 5, 5
a: gas sampling system, 6: chimney, 10: refuse incinerator, 16,
16a: imaging camera, 21: cooling tower, 22: dust collector,
23: gas heater, 24: denitration device, 25: activated carbon injection equipment, 31: various gas analyzers, 32: dioxin measuring device, 41, 41a: data recording device, 42, 42
a: inference engine, 43, 43a: rule base, 45
... Image processing apparatus, 111 ... Dry stalker, 112 ... Combustion stalker, 113 ... Post combustion stalker, 211 ... Water supply source, 212 ... Water supply amount adjustment valve, 251 ... Activated carbon injection source, 252 ... Activated carbon amount adjustment valve, 321 ... Gas Preprocessing section,
321a: filter, 321b: switching valve, 32
1c: heating pipe, 321d: needle valve, 321e
... Exhaust pump, 321f ... Exhaust pipe, 321g ... Exhaust gas probe, 321h ... Standard gas generator, 322 ... Monitor, 322a ... Atmospheric pressure chemical ion source, 322b ... Mass analyzer, 322c ... Vacuum pump, 323 ... Data processing Part, 323a... Amplifier, 323b.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masayuki Taniguchi 7-1-1, Omika-cho, Hitachi City, Ibaraki Prefecture Within Hitachi Research Laboratory, Hitachi, Ltd. (72) Inventor Minoru Sakairi 1-280 Higashi Koikebo, Kokubunji-shi, Tokyo F-term in Central Research Laboratory, Hitachi, Ltd. 3K062 AA02 AB01 AC01 BA02 BB04 CA01 CB04 CB08 DA02 DA08 DA23 DA24 DA26 DB03 DB08 DB09 DB13 DB28

Claims (14)

[Claims] 1. A waste incinerator having a waste incinerator and an operating end for controlling the state of the waste incinerator, wherein a gas in the waste incinerator or a gas for collecting exhaust gas from the waste incinerator is provided. Sampling means, a dioxin measuring device for measuring the amount of dioxins and / or dioxin precursor in the sample gas collected by the gas sampling means, and dioxins and / or dioxin precursor measured by the dioxin measuring device Control means for determining the operation amount of the operation end in accordance with the amount of the operation end, and outputting the operation amount to the operation end, wherein the dioxin measurement device converts the sample gas collected by the gas collection means Atmospheric pressure ionization means for ionizing under atmospheric pressure, and dioxins and / or dioxin in the sample gas ionized by the atmospheric pressure ionization means It has a mass spectrometric means for performing mass analysis of emissions precursor, a refuse incineration facility, characterized in that. 2. The refuse incineration plant according to claim 1, wherein the dioxin measuring device performs the mass spectrometry using a predetermined relative relationship between the mass of the dioxin precursor and the mass of the dioxins. Waste incineration equipment, comprising: estimating means for estimating the mass of the dioxins from the mass of the dioxin precursor mass-analyzed by the means. 3. The refuse incineration plant according to claim 1, wherein the dioxin measuring device is the dioxin and / or the dioxin having a dichlorine substitution product or more at a level of 1000 ng / Nm ^3. A refuse incineration plant characterized in that the concentration of the precursor is measured within an analysis time of 5 seconds and within a measurement error of ± 10%. 4. The refuse incineration plant according to claim 1, wherein the refuse incinerator is supplied into the refuse incinerator as the operating end controlled by the control means. Refuse supply speed adjustment means for adjusting the supply rate of refuse, primary air amount adjustment means for adjusting the supply amount of primary air supplied into the refuse incinerator, and primary air temperature adjustment means for adjusting the temperature of the primary air. A secondary air amount adjusting means for adjusting a supply amount of the secondary air supplied downstream from a position where the primary air is supplied, and an orientation for supplying the secondary air into the incinerator. Waste incineration equipment, wherein at least one of secondary air supply direction adjusting means is provided. 5. A refuse incineration plant having a refuse incinerator, an exhaust gas treatment system for treating exhaust gas from the refuse incinerator, and a chimney for exhausting the exhaust gas passing through the exhaust gas treatment system. A plurality of gas sampling means for sampling gas from the refuse incinerator to the chimney at different locations, and dioxins and / or dioxin precursors in each sample gas sampled by the plurality of gas sampling means A plurality of dioxin measuring devices each measuring the amount of dioxin, and from the amount of each dioxin and / or dioxin precursor measured by the plurality of dioxin measuring devices, the main generation factor of dioxins is a plurality of gas sampling. It is determined which of the means is based on a state on the upstream side of the gas sampling means (hereinafter referred to as the specific gas sampling means), and The operation end of the equipment upstream of the specific gas sampling means, which is an operation end that affects the amount of dioxins produced according to the operation amount of the operation end, is collected by the specific gas sampling means. A refuse incineration facility, comprising: control means for outputting an operation amount determined according to the amount of dioxins and / or dioxin precursors in the gas. 6. The refuse incineration plant according to claim 5, wherein one of the plurality of gas collecting means is a gas in the refuse incinerator or an exhaust gas from the refuse incinerator. Incinerator gas sampling means for sampling the exhaust gas before reaching the exhaust gas treatment system, wherein one gas sampling means is the exhaust gas in the exhaust gas treatment system, or the gas exhausted from the exhaust gas treatment system. Processing system gas sampling means for sampling exhaust gas, wherein one of the plurality of dioxin measurement devices is a dioxin and / or dioxin precursor in a sample gas sampled by the incinerator gas sampling device; An incinerator dioxin measuring device for measuring the amount of dioxins, wherein one dioxin measuring device is used for measuring dioxins and the like in a sample gas collected by the processing system gas collecting means. And / or a processing system dioxin measuring device for measuring an amount of a dioxin precursor, wherein the control means includes: an amount of dioxins and / or a dioxin precursor measured by the incinerator dioxin measuring device; From the amount of dioxins and / or dioxin precursors measured by the apparatus, it is determined whether the main generation factor of dioxins is the state of the refuse incinerator or the state of the exhaust gas treatment system, Of the refuse incinerator and the exhaust gas treatment system, a dioxin and / or dioxin precursor measured by the dioxin measuring device of the facility is connected to the operating end of the facility having a major source of dioxins. A refuse incineration plant, which outputs a manipulated variable determined according to the amount of a substance. 7. The refuse incineration plant according to claim 6, wherein the refuse incinerator serves as the operating end controlled by the control means, and controls a supply rate of refuse supplied to the refuse incinerator. Refuse supply speed adjusting means, primary air amount adjusting means for adjusting the supply amount of primary air supplied into the refuse incinerator, primary air temperature adjusting means for adjusting the temperature of the primary air, and the primary air is supplied. Secondary air amount adjusting means for adjusting the supply amount of secondary air supplied downstream from the position, and secondary air supply direction adjusting means for adjusting the direction in which the secondary air is supplied into the incinerator. And the exhaust gas treatment system has a dust collecting device for removing dust in the exhaust gas, and sends the dust to the dust collecting device as the operating end controlled by the control means. The temperature of the exhaust gas An exhaust gas temperature adjusting means for, among the activated carbon supply amount adjusting means for blowing activated carbon into the exhaust gas is sent to the dust collecting device, it has at least one, refuse incinerators, characterized in that. 8. The refuse incineration plant according to claim 7, further comprising: an image pickup unit for picking up an image of a flame in the refuse incinerator, wherein the control unit controls various amounts of dioxins and / or dioxin precursors and the refuse incineration. For the various flame patterns in the furnace, using the rule in which the operating end to be operated is determined, the amount of dioxins and / or dioxin precursor measured by the incinerator dioxin measuring device and imaged by the imaging means A waste incineration facility, wherein an operation end is determined in accordance with the flame pattern and the operation of the operation end is controlled. 9. A refuse incineration facility having a refuse incineration furnace and a plurality of operating terminals for controlling the state of the refuse incineration furnace, wherein a gas in the refuse incinerator or an exhaust gas from the refuse incineration is sampled. A gas sampling unit that measures the amount of dioxins and / or a dioxin precursor in the sample gas collected by the gas sampling unit; and an imaging unit that captures an image of a flame in the refuse incinerator, For the various amounts of dioxins and / or dioxin precursors and various flame patterns in the refuse incinerator, the dioxin measurement is performed by using a rule in which an operation end to be operated is determined among a plurality of operation ends. Determining the amount of dioxins and / or dioxin precursor measured by the device and the operation end according to the pattern of the flame imaged by the imaging means, Control means for controlling the operation of the operating end. 10. The refuse incineration plant according to claim 5, wherein the dioxin measuring device ionizes the sample gas collected by the gas collecting device under atmospheric pressure. And mass spectrometry means for mass spectrometry analysis of dioxins and / or dioxin precursors in the sample gas ionized by the atmospheric pressure ionization means. 11. The refuse incinerator according to claim 1, wherein said refuse incinerator is a stalker furnace in which a stalker moves, and said control means controls said refuse incinerator. The refuse incineration facility, wherein a stalker speed adjusting means for adjusting a moving speed of the stalker is provided as the operation end. 12. A method for controlling a refuse incineration plant having a refuse incinerator and an operating end for controlling the state of the refuse incinerator, wherein a gas in the refuse incinerator or an exhaust gas from the refuse incinerator is discharged. A gas sampling step of sampling, a dioxin measuring step of measuring the amount of dioxins and / or a dioxin precursor in the sample gas collected in the gas sampling step, and dioxins and / or measured in the dioxin measuring step A control step of determining the operation amount of the operation end according to the amount of the dioxin precursor and outputting the operation amount to the operation end, wherein the dioxin measurement step is collected in the gas collection step. The sample gas is ionized by corona discharge under atmospheric pressure, and the mass of dioxins and / or dioxin precursor in the ionized sample gas To analyze, the control method of waste incineration facilities, characterized in that. 13. A refuse incineration system comprising: a refuse incinerator; an exhaust gas treatment system for treating exhaust gas from the refuse incinerator; and a chimney for exhausting the exhaust gas passing through the exhaust gas treatment system. In the control method, a gas sampling step of collecting gas from the refuse incinerator to the chimney at different points, and dioxins and / or dioxin in each sample gas collected at a plurality of points in the gas sampling step From the dioxin measurement step of measuring the amount of each precursor, and the amount of each dioxin and / or dioxin precursor measured in the dioxin measurement step, the main generation factor of dioxins is determined by a plurality of gas sampling points. Judge which of the gas sampling points (hereinafter referred to as the specified gas sampling point) is due to the condition on the upstream side,
For the operation end of the equipment upstream of the specific gas sampling point, the operation end that affects the amount of dioxins produced in accordance with the operation amount of the operation end, the sampling is performed at the specific gas sampling point. A control step of outputting a manipulated variable determined according to the amount of dioxins and / or dioxin precursors in the waste gas. A method for controlling a refuse incineration plant, comprising: 14. A method for controlling a refuse incineration plant having a refuse incinerator and a plurality of operating terminals for controlling the state of the refuse incinerator, wherein the gas in the refuse incinerator or the exhaust from the refuse incinerator is provided. A gas collection step of collecting gas, a dioxin measurement step of measuring the amount of dioxins and / or a dioxin precursor in the sample gas collected in the gas collection step, and an imaging of imaging a flame in the refuse incinerator Steps, for various amounts of dioxins and / or dioxin precursors and various flame patterns in the refuse incinerator, using a rule in which the operating end to be operated among a plurality of operating ends is defined, Operation according to the amount of dioxins and / or dioxin precursor measured in the dioxin measurement step and the flame pattern imaged in the imaging step Controlling the operation of the operating end by defining an end; and controlling the operation of the waste incinerator.