JP4514543B2 - Device for measuring and suppressing harmful trace substances - Google Patents

Description

The present invention relates to a measuring device for harmful trace substances contained in exhaust gas after dust collection treatment and a control apparatus for the harmful trace substances.

  In general, waste such as municipal waste is put into an incinerator in an incineration facility and incinerated. In addition, exhaust gas generated by incineration in an incinerator is heat recovery and temperature reduction treatment with a boiler and economizer, etc., blow-in treatment with alkali chemicals (slaked lime, baking soda, etc.) for removing acid gases (HCl, SOx, etc.) After a blowing process of an adsorbent (activated carbon, baking soda, etc.) for adsorbing dioxins is sequentially performed, the dust is collected by a dust collector. Thus, the exhaust gas from which the adsorbent that adsorbs the salt and dioxins generated by neutralization of dust, acid gas and alkali chemicals is collected and removed becomes clean gas and is discharged out of the system.

  By the way, in recent years, in order to ensure the safety of local communities, prevent environmental pollution, etc., the emission regulations of harmful trace substances in exhaust gas, especially dioxins with extremely high toxicity, have been strengthened. Incineration facilities are required to measure dioxins at least once a year, report them to prefectural governors, and comply with emission standards.

  Examples of the measuring method of the dioxins include a measuring method according to Article 2 of the Enforcement Regulations of the Special Measures Law for Countermeasures against Dioxins and JIS K 0311. Hereinafter, a measurement method according to Article 2 of the Enforcement Regulations for the Special Measures Law for Countermeasures against Dioxins and JIS K 0311 will be described with reference to FIG.

  As shown in FIG. 3, the first and second water tanks 102a and 102a are each cooled by ice or dry ice after the exhaust gas extracted from the flue after dust removal is filtered by the filter paper 101. 102b, first air tank 103a, packed column 104 filled with an adsorbent (for example, XAD resin), liquid tank 105 in which diethylene glycol is stored, and second air tank 103b are sequentially passed by suction pump 106. Aspirated and discharged out of the system. In the figure, reference numeral 107 denotes a flow meter. On the other hand, dioxins contained in the exhaust gas are absorbed and collected by the filter paper 101, the water in the first and second water tanks 102a and 102b, the adsorbent in the packed column 104, and diethylene glycol in the liquid tank 105.

  After the exhaust gas is sucked for 4 hours or more, the concentration of dioxins is detected for each of the filter paper 100, the water in each of the water tanks 102a and 102b, the adsorbent in the packed column 104, and the diethylene glycol in the liquid tank 105. In accordance with a predetermined procedure. Thereby, the dioxin density | concentration in waste gas is detected as a exact numerical value. In addition, it has been clarified that most (94 to 99%) of dioxins in the exhaust gas is collected by the water stored in the first and second water tanks 102a and 102b.

  However, although the conventional measuring method has an advantage that the concentration of dioxins in the exhaust gas can be accurately measured, it is necessary to continue to suck the exhaust gas for more than 4 hours according to JIS regulations, and the collected gas is collected. There is a problem that it is necessary to carry out extraction operation of dioxins, measurement with a high resolution mass spectrometer, etc., and it takes a month or more for the measurement result to be obtained. In addition, the measurement of the dioxins is stipulated to be at least once a year in Article 28 of the Special Measures Law for Countermeasures against Dioxins. It is usually performed only twice. Therefore, the non-measurement period becomes longer, and during that time it is unclear whether or not the emission regulations for dioxins are being complied with. For this reason, constant monitoring of dioxin concentrations in exhaust gas is frequently requested by the local residents. However, all of the conventional methods for measuring dioxins take time to measure, so respond to such requests from the local residents. The fact is that we have not been able to.

  In addition, as described above, in the measurement method, since it takes time until the measurement result is obtained, the measurement result can be used only for determining whether or not the emission standard is complied with. It was impossible to adjust the blowing amount of the dioxins adsorbent using the measurement results and to perform operation control to suppress the discharge of dioxins. For this reason, the adsorbent injection amount with sufficient margin is set in anticipation of fluctuations in the concentration of dioxins, but it is necessary to give priority to the removal of dioxin concentration, so the adsorbent injection amount is excessive. There is a problem in that it tends to be set, resources cannot be used effectively, and the running cost increases.

  On the other hand, in recent years, an attempt has been made to directly measure the exhaust gas downstream of the dust collector. However, in the case of dioxins, the concentration of dioxins contained in the exhaust gas downstream of the dust collector is extremely low, regardless of whether the legal concentration is exceeded or not. Phenols etc. are measured as dioxin substitution indicators, but the concentration fluctuations of dioxins are often not correctly reflected, and there is a possibility that a large error may occur due to fluctuations in the flow rate of exhaust gas, fluctuations in properties such as moisture, etc. There is a problem that the accuracy of the measurement result cannot be trusted and is difficult to use for various controls.

The present invention has been made to solve such problems, and when the concentration of harmful trace substances is measured, the concentration fluctuation of the hazardous trace substances in the actual exhaust gas is correctly reflected in the measurement results. it is not that it is possible to enhance the reliability of measurement results, and the harmful trace substance concentration of dioxins in an exhaust gas discharged, quickly and with high accuracy measurement and real-time, harmful trace substance concentration in the exhaust gas In addition to providing a measurement device for hazardous trace substances that can be monitored at all times and the measurement results can be used as a control index, the amount of adsorbent blown can be reliably controlled in response to fluctuations in the concentration of harmful trace substances. An object of the present invention is to provide a device for suppressing harmful trace substances that can be adjusted.

In order to achieve the above object, a measuring device for harmful trace substances according to the first invention comprises:
Withdrawing an exhaust gas portion at the downstream side of the dust collecting means for treating an exhaust gas, a measuring apparatus of toxic trace substances for detecting the concentration of hazardous trace substances contained in the flue gas continuously,
An absorption liquid supply source for supplying an absorption liquid for absorbing and collecting harmful trace substances in the exhaust gas at a constant supply rate, and an absorption liquid tank for temporarily storing the absorption liquid supplied from the absorption liquid supply source And a drawing-in duct for supplying the exhaust gas extracted from the downstream side of the dust collecting means into the absorbent in the absorbent tank at a constant supply rate, and a harmful trace substance by the absorbent in the absorbent tank A reflux duct that circulates exhaust gas after being collected to the chimney, a liquid pipe that discharges the absorbent in the absorbent tank at a discharge speed that is the same as the supply speed of the absorbent, and circulates in the liquid pipe And a harmful trace substance concentration detecting means for continuously and in real time detecting the concentration of harmful trace substances in the absorbing liquid .

In the first invention, the harmful trace substance concentration detecting means includes a laser meter, and is adapted to irradiate and receive the laser beam from the laser meter in the absorbing liquid in the liquid tube, and the laser beam before irradiation, It is preferable to analyze the wavelength attenuated and absorbed by the received laser beam after irradiation and calculate the concentration of harmful trace substances based on the analysis result (second invention). .

Moreover, the control device for harmful trace substances according to the third invention is:
A device for suppressing harmful trace substances comprising the device for measuring harmful trace substances according to the first invention or the second invention,
The upstream duct arranged upstream of the dust collecting means is provided with a blowing device for injecting an adsorbent for adsorbing / removing harmful trace substances in the exhaust gas, and measured by the harmful trace substance measuring device. based on the concentration of toxic trace substances, it is characterized in providing a control mechanism for feedback controlling the blowing amount of the adsorbent by the purging means.

  According to the first invention, harmful trace substances in the exhaust gas are collected in the absorbing solution. Therefore, by adjusting the flow rate of the absorption liquid as appropriate (for example, by suppressing the supply / discharge speed of the absorption liquid sufficiently lower than the supply speed of the exhaust gas), the concentration of harmful trace substances in the absorption liquid is reduced to a certain level. High concentration can be maintained. Therefore, when measuring the concentration of harmful trace substances in the absorption liquid and calculating the concentration of harmful trace substances in exhaust gas based on this measurement result, the concentration fluctuations of the actual hazardous trace substances in the exhaust gas are correctly measured. Further, the reliability of the obtained result (the concentration of harmful trace substances in the absorption liquid and the exhaust gas) can be improved.

Further , according to the present invention, since harmful trace substances in exhaust gas are collected by an absorption liquid and the harmful trace substances in the absorption liquid are measured, the concentration of harmful trace substances in the absorption liquid is determined. It can measure with high accuracy. In addition, the concentration of harmful trace substances in the absorption liquid is detected continuously and in real time by means of the hazardous trace substance concentration detection means. The concentration can be calculated quickly and continuously. Therefore, it is possible to constantly monitor whether or not the incineration facility or the like complies with the emission regulations of harmful trace substances, so that it is possible to give the residents a sense of security. Furthermore, as described above, since the concentration of harmful trace substances in the exhaust gas is rapidly calculated based on the concentration of harmful trace substances in the absorption liquid, the calculation result can be used as an index for various controls.

  Next, according to the third aspect of the invention, the harmful trace substance concentration in the exhaust gas is calculated based on the harmful trace substance concentration in the absorption liquid detected in real time by the harmful trace substance concentration detection means, and the harmful trace substance concentration in the exhaust gas is calculated. Since the amount of adsorbent blown is feedback controlled in accordance with the fluctuation of the trace substance concentration, the harmful trace substance concentration in the exhaust gas can be reliably suppressed to a lower concentration than the legal value. Moreover, since the concentration fluctuation of harmful trace substances in the exhaust gas is reflected in the amount of adsorbent blown, there is an effect that excessive blowing of the adsorbent can be prevented.

Next, specific embodiments of the device for measuring harmful trace substances and the suppressing device according to the present invention will be described with reference to the drawings.

  FIG. 1 shows a schematic configuration diagram of an incineration facility according to an embodiment of the present invention, and FIG. 2 shows a schematic configuration diagram of an exhaust gas sampling device.

  Generally, the waste conveyed to the incineration facility 1 is crushed to an appropriate size and then put into the incinerator 2 for incineration. The exhaust gas generated by the incineration is reduced in temperature by a boiler device 3 disposed on the downstream side of the incinerator 2 and an economizer (and / or a water spray gas cooling tower) 4, and then a dust collecting device (dust collecting means) 6. The upstream side duct (hereinafter referred to as “upstream side duct”) 5 is supplied to the dust collector 6 and collected, and the downstream side of the dust collector 6 (hereinafter referred to as “downstream side”). It is discharged out of the system through 7 and the chimney 8. In addition, what is shown by the code | symbol 9 in the figure is an air attraction apparatus for attracting | sucking exhaust gas toward the chimney 8. FIG.

  Since the exhaust gas discharged from the incinerator 2 contains not only dust but also harmful trace substances typified by dioxins that have a significant adverse effect on the human body, and acidic gases such as HCl and SOx, these dioxins. It is necessary to reliably remove the gases and acid gases from the exhaust gas. Accordingly, an adsorbent (activated carbon) for adsorbing dioxins and an alkaline agent (for example, slaked lime) for neutralizing acidic gas are blown into the incineration facility 1 into the exhaust gas in the upstream duct 5. A blowing device 10 is attached.

  The blowing device 10 includes a blowing blower 11, a blowing duct 12 that connects the blowing blower 11 and the upstream duct 5, an adsorbent storage tank 13 that stores the adsorbent, and an alkali that stores an alkaline agent. The medicine storage tank 14 is provided. In addition, supply devices 13a and 14a are respectively attached to the lower part of the adsorbent storage tank 13 and the alkaline drug storage tank 14, and the supply amount of each drug is adjusted by the supply devices 13a and 14a. It has become. Further, the supply device 13a of the adsorbent storage tank 13 is provided with a control mechanism 13b for controlling the amount of adsorbent blown based on the calculation result by the controller 30 described later.

  Further, the incineration facility 1 is provided with a sampling device 20 that extracts a part of the exhaust gas in the chimney 8 and continuously detects the concentration of dioxins in the exhaust gas.

  As shown in FIG. 2, the sampling device 20 includes an absorption liquid supply source 21 that supplies an absorption liquid for absorbing and collecting dioxins and the like in exhaust gas at a constant supply speed v, and this absorption. Absorption liquid tank 22 that temporarily stores the absorption liquid supplied from liquid supply source 21 at supply speed v and the exhaust gas extracted from chimney 8 in the absorption liquid in absorption liquid tank 22 at a constant supply speed F. A suction duct 23a for supplying the exhaust gas to the chimney 8, a reflux duct 23b for refluxing the exhaust gas after the dioxins and the like are collected by the absorbent in the absorbent tank 22, and the reflux duct 23b. A reflux pump 23c is provided. In addition, a liquid pipe 24 that discharges the internal absorption liquid to the downstream side at a discharge speed v (same speed as the supply speed v) is attached to the absorption liquid tank 22. An analyzer (hazardous trace substance concentration detecting means) 25 that continuously and in real time detects the concentration of dioxins in the absorbing solution flowing through the liquid pipe 24 is inserted.

  The analyzer 25 includes a laser meter, and the laser beam from the laser meter is irradiated into the absorbing liquid in the liquid tube 24 and received. Then, the laser beam before irradiation is compared with the received laser beam after irradiation, and the wavelength attenuated and absorbed by passing through the absorption liquid is analyzed. Based on the analysis result, The dioxins concentration is detected continuously and in real time.

  The absorption liquid after being measured by the analyzer 25 is discharged to the waste liquid tank 26 and reused for spraying in the incinerator 2.

  In the present embodiment, the incineration facility 1 is provided with a controller 30 including a data input / output unit, a storage unit, and a calculation unit for performing a calculation described later. A detection result from the analyzer 25 is input to the input unit of the controller 30 as needed. Further, the storage unit stores dioxin concentration set values used when calculating the amount of adsorbent blowing, correlation data of dioxin adsorption rate-adsorbent blowing amount, and the like. Here, the set value is a target value for the concentration of dioxins in the exhaust gas, and is set to a concentration that is at least lower than the legal value. Further, the correlation data is obtained in advance based on actual measurement of the correlation between the adsorption rate of dioxins with respect to the adsorbent and the amount of adsorbent blown, and although illustration is omitted, the amount of blow increases. Along with this, the adsorption rate of dioxins tends to increase.

  The calculation unit of the controller 30 calculates a dioxin concentration in the exhaust gas based on the dioxin concentration in the absorption liquid input from the analyzer 25 (described later), and the calculated dioxins in the exhaust gas. Based on the concentration, the set value, and the correlation data, a function (described later) for calculating the amount of adsorbent blown into the exhaust gas in the upstream duct 5 is provided. The adsorbent blowing amount calculated by the calculation unit is transmitted from the output unit to the control mechanism 13b provided in the supply device 13a of the adsorbent reservoir 13.

  In the present embodiment, the exhaust gas extracted from the chimney 8 is supplied into the absorption liquid in the absorption liquid tank 22 through the drawing duct 23a and stirred together with the absorption liquid. Thus, dioxins in the exhaust gas are absorbed and collected in the absorption liquid. The exhaust gas after the dioxins are absorbed is returned to the chimney 8 through the reflux duct 23b and discharged out of the system. On the other hand, the absorption liquid in which the dioxins in the absorption liquid tank 22 are collected is discharged at a discharge speed v, and then circulates in the liquid pipe 24, and the concentration of dioxins is detected by the analyzer 25. (Details will be described later).

  The concentration of dioxins in the absorption liquid obtained by the analyzer 25 is sequentially transmitted to the controller 30. Then, in the calculation unit of the controller 30, the concentration of dioxins in the exhaust gas is calculated based on the concentration of dioxins in the absorption liquid, and in the upstream duct 5 based on the calculation result and the set value / correlation data. The amount of adsorbent to be blown into the exhaust gas is estimated. This blowing amount is transmitted to the control mechanism 13b.

The control mechanism 13b changes the supply speed of the supply device 13a in accordance with the blowing amount transmitted from the controller 30, and adjusts the supply amount of the adsorbent to the blowing duct 12 . In this way, the amount of adsorbent blown is feedback controlled in accordance with the dioxin concentration in the exhaust gas continuously obtained in real time.

  Next, a method for calculating the dioxin concentration in the exhaust gas from the dioxin concentration in the absorption liquid obtained by the analyzer 25 will be described.

  In the following description, an example in which the concentration of dioxins in the absorption liquid is detected at a detection time Δt from time t = t1 to time t = t2 and the concentration of dioxins in the exhaust gas is calculated based on the detection result. explain. Here, at time t = t1 and t2, the dioxins concentration in the absorption liquid detected by the analyzer 25 is C1 and C2, respectively, and the dioxin concentration in the absorption liquid is represented by a function C (t). The function C (t) is obtained by measuring and plotting the dioxins concentration in the absorbing solution every minute time dt using the analyzer 25 during the period from time t = t1 to t2. The function can be obtained by appropriately selecting a function that overlaps each point or passes through the vicinity of each point. Here, if the volume of the absorbing liquid stored in the absorbing liquid tank 22 is V, the absorbing liquid is supplied to the absorbing liquid tank 22 at a constant supply speed v as described above. Since the processing liquid is discharged at a discharge speed v that is the same as the supply speed v, V is a constant. Further, as described above, the supply rate of the exhaust gas to the absorbent tank 22 is defined as a constant F, and the average value of the dioxin concentration between t1 and t2 in the exhaust gas is determined as X.

  First, the balance of the dioxin amount in the absorbent tank 22 from time t = t1 to t2 is calculated.

  The balance can be obtained by taking the difference between the amount of dioxins in the absorbent in the absorbent bath 22 at time t = t2 and the amount of dioxins at time t = t1. Here, the amount of dioxins in the absorption liquid at time t = t1, t2 is the product V · C2, of the volume V of the absorption liquid and the concentration of dioxins C1, C2 in the absorption liquid at time t = t1, t2. It is obtained by V · C1. Therefore, the balance is obtained by the following equation (1).

  The balance is calculated from the amount of dioxins flowing into the absorbent tank 22 from time t = t1 to t2, that is, until the detection time Δt elapses, It can also be obtained by taking the difference between the amount of dioxins that have flowed out. Here, the inflow amount of dioxins during the detection time Δt is obtained by the product F · X · Δt of the supply rate F of the exhaust gas, the average value X of the concentration of dioxins in the exhaust gas, and the detection time Δt. Further, the outflow amount can be obtained by integrating the product v · C (t) · dt of the absorption liquid discharge speed v, the concentration function C (t), and the minute time dt between t1 and t2. . Therefore, the balance is also expressed as the following equation (2).

  From this, the following equation (3) holds.

  Therefore, the average dioxin concentration X in the exhaust gas is obtained by the following equation (4).

  In the present embodiment, as described above, the exhaust gas is passed through the absorption liquid (water) only once, and the absorption liquid absorbs dioxins in the exhaust gas, and the concentration of dioxins in the absorption liquid is determined. Compared to the method of collecting and analyzing dioxins in exhaust gas in multiple stages with filter paper, water, adsorbent, and diethylene glycol, as in the conventional measurement method according to JIS regulations. It can be said that the accuracy is slightly inferior. However, in the conventional method, since most of the dioxins (about 94 to 99%) are found to be absorbed and repaired by water, the exhaust gas is discharged once as in this embodiment. Even if it is a simple measurement method that passes through the absorption liquid only, detects the dioxin concentration in the absorption liquid, and calculates the dioxins in the exhaust gas based on the detection result, a predetermined accuracy can be ensured. it is obvious. Therefore, it can be said that the dioxin concentration in the exhaust gas required by the present embodiment has sufficient accuracy to be used as an index for controlling the adsorbent blowing.

  Next, adsorbent blowing control based on the dioxin concentration in the exhaust gas calculated in this way will be described.

  First, the concentration of dioxins in the exhaust gas is calculated based on the concentration of dioxins in the absorption liquid obtained by the analyzer 25 and the equation (4). Next, based on this calculation result (actual dioxin concentration in the exhaust gas) and the set concentration of dioxins stored in the storage unit of the controller 30, the actual dioxin concentration in the exhaust gas matches the set concentration. The adsorption rate of dioxins is obtained. Next, based on the correlation between the adsorption rate of the dioxins thus obtained and the adsorption rate of the dioxins stored in the storage unit-the amount of the adsorbent, the amount of the adsorbent that is to be blown into the exhaust gas. The amount is estimated, and the estimation result is transmitted to the control mechanism 13b provided in the supply device 13a of the adsorbent storage tank 13. The control mechanism 13b adjusts the amount of adsorbent blown from the supply device 13a to the blowing duct 12 based on the transmitted amount of blown air, so that the adsorbent to the exhaust gas in the upstream duct 5 is adjusted. Feedback control of the blowing amount.

  Further, even when the amount of adsorbent obtained by calculation is blown, the dioxin concentration continuously measured on the downstream side of the dust collector 6 is not suppressed as expected, and the legal value is not reduced. If it exceeds, the controller 30 corrects the correlation data between the adsorption rate and the adsorbent blowing amount.

  Thereby, the dioxin density | concentration in the waste gas discharged | emitted is suppressed to a density | concentration lower than a legal value.

  In the present embodiment, by using the analyzer 25 equipped with a laser meter, the concentration of dioxins in the absorption liquid is detected in real time, and the calculation of the concentration of dioxins in the exhaust gas is quickly performed based on the detection result. To be done. Accordingly, the concentration of dioxins in the exhaust gas can be constantly monitored, and there is an effect that it is possible to increase the sense of security of the surrounding residents. In addition, the dioxin concentration of the exhaust gas is obtained continuously in real time based on the detection result by the analyzer 25, and has a predetermined accuracy as described above. It can be used as an indicator.

  Further, in the present embodiment, the dioxin concentration in the exhaust gas discharged from the chimney 8 to the outside of the system based on the dioxin concentration of the exhaust gas and the correlation data is set to a predetermined set value (a legal value). Since the adsorbent blowing amount is feedback-controlled so as to coincide with the low concentration), the concentration of dioxins in the exhaust gas discharged can be reliably suppressed to a concentration lower than the legal value. In addition, since fluctuations in the concentration of dioxins in the exhaust gas are reflected in the amount of adsorbent blown, there is an effect that excessive blowing of the adsorbent can be prevented.

  In addition, when the dioxin concentration in the exhaust gas is directly detected, the dioxin concentration in the exhaust gas is too low for direct detection, and the exhaust gas has a large change in flow rate and changes in properties such as moisture content. Is likely to occur, which may cause a large error in the detected dioxin concentration. In contrast, in the sampling device 20 of the present embodiment, the exhaust gas in the chimney 8 is extracted, and dioxins in the exhaust gas are once collected by the absorption liquid in the absorption liquid tank 22, and then the absorption liquid is fixed at a constant speed. v is circulated in the liquid pipe 24 and the concentration of dioxins in the absorption liquid is detected. By appropriately adjusting the supply / discharge speed v of the absorption liquid (for example, the absorption liquid By adjusting the supply rate / discharge rate v sufficiently low relative to the exhaust gas supply rate F, the concentration of dioxins in the absorption liquid is maintained at a predetermined concentration (that is, the concentration can be detected with high accuracy). It is also possible to suppress errors caused by changes in the flow rate of the absorbing liquid and fluctuations in properties. Therefore, there is an advantage that the obtained result (the dioxin concentration in the absorbing solution and the dioxin concentration in the exhaust gas calculated therefrom) can be trusted.

  In the present embodiment, the description is limited to the detection of the concentration of dioxins in the exhaust gas. However, polycyclic aromatic hydrocarbons that are unregulated at the present time and are considered to have an effect on the human body, mercury, etc. Thus, continuous and real-time measurement of other harmful trace substances can be performed using the same method as in the case of dioxins. In addition, depending on the concentration of harmful trace substances (polycyclic aromatic hydrocarbons, mercury, etc.) detected in this way, the amount of adsorbent, etc. controlled is controlled, and the harmful trace substances (polycyclic aromatic hydrocarbons, mercury, etc.) are controlled. Of course, it is also possible to suppress the concentration in the exhaust gas around the set value.

  Moreover, in each said embodiment, although activated carbon was used as an adsorbent, baking soda can be used instead of activated carbon. Further, water or diethylene glycol can be used as the absorbing liquid.

  Moreover, in each said embodiment, although exhaust gas is extracted from the chimney 8, if it is exhaust gas after dust collection, there is no problem even if it extracts, for example, exhaust gas in the downstream duct 7 is exhausted. You may make it extract. Needless to say, even in such a case, it is possible to obtain the same effects as those of the above-described embodiment.

  In each of the embodiments described above, the concentration of dioxins in the absorption liquid is detected in real time using the analyzer 25 equipped with a laser meter. However, the concentration of dioxins in the absorption liquid is detected in real time. If possible, it is possible to use another type of analyzer such as an analyzer that detects the concentration of dioxins by comparing the killing rate of microorganisms before and after the passage of dioxins.

  In addition, since it is not directly related to the gist of the present invention, no mention was made of alkali chemical blowing control for neutralizing and removing HCl, SOx, etc., but in addition to the adsorbent blowing control, Of course, it is possible to control the injection of the alkaline agent. As a method for controlling the injection amount of the alkaline agent, for example, it is necessary and sufficient to detect the HCl concentration in the exhaust gas in the upstream duct 5 and remove the acid gas component based on the detection result and the measured data. Conventionally used techniques such as determining the amount of injection of the alkaline agent and performing feedback control of the alkaline agent can be employed.

  The idea of extracting the exhaust gas downstream of the dust collector 6 and collecting the dioxins in the exhaust gas with the absorption liquid, and continuously detecting the concentration of the dioxins collected in the absorption liquid in real time. The idea of calculating the dioxin concentration in the exhaust gas and the idea of controlling the amount of adsorbent blown based on the dioxin concentration in the exhaust gas are not limited to the incineration facility 1, but the dioxins It is possible to apply to exhaust gas treatment equipment in general.

Schematic configuration diagram of incineration equipment according to an embodiment of the present invention Schematic configuration diagram of exhaust gas sampling device Diagram for explaining the measurement method of dioxin concentration according to Article 2 of the Special Measures Law Enforcement Regulations for Dioxins Countermeasures and JIS K 0311

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Incineration equipment 5 Upstream side duct 6 Dust collector 7 Downstream side duct 8 Chimney 10 Blowing device 13 Adsorbent storage tank 13a Supply apparatus 13b Control mechanism 20 Sampling apparatus 22 Absorbing liquid tank 25 Analyzer 30 Controller

Claims (3)

Withdrawing an exhaust gas portion at the downstream side of the dust collecting means for treating an exhaust gas, a measuring apparatus of toxic trace substances for detecting the concentration of hazardous trace substances contained in the flue gas continuously,
An absorption liquid supply source for supplying an absorption liquid for absorbing and collecting harmful trace substances in the exhaust gas at a constant supply rate, and an absorption liquid tank for temporarily storing the absorption liquid supplied from the absorption liquid supply source And a drawing-in duct for supplying the exhaust gas extracted from the downstream side of the dust collecting means into the absorbent in the absorbent tank at a constant supply rate, and a harmful trace substance by the absorbent in the absorbent tank A reflux duct that circulates exhaust gas after being collected to the chimney, a liquid pipe that discharges the absorbent in the absorbent tank at a discharge speed that is the same as the supply speed of the absorbent, and circulates in the liquid pipe A device for measuring harmful trace substances, comprising: a harmful trace substance concentration detecting means for continuously and in real time detecting the concentration of harmful trace substances in the absorbing liquid . The harmful trace substance concentration detecting means includes a laser meter, and receives the laser beam from the laser meter in the absorbing liquid in the liquid tube and receives the laser beam before irradiation and after irradiation. The harmful trace substance according to claim 1, wherein the wavelength of the attenuated trace substance is analyzed by a laser beam through the absorption liquid, and the concentration of the harmful trace substance is calculated based on the analysis result. Measuring device . A device for suppressing harmful trace substances comprising the device for measuring harmful trace substances according to claim 1 or 2,
The upstream duct arranged upstream of the dust collecting means is provided with a blowing device for injecting an adsorbent for adsorbing / removing harmful trace substances in the exhaust gas, and measured by the harmful trace substance measuring device. based on the concentration of toxic trace substances, suppressing apparatus of harmful trace substances and providing a control mechanism for feedback controlling the blowing amount of the adsorbent by the purging means.

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