JP2018036166A - Analyzer, method for removing mercury, incinerator system, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To analyze mercury contained in a measurement target gas by detection of 0-valent mercury alone.SOLUTION: A first analyzer 5 includes a light source 532, a detector 533, and an operation controller 55. The light source 532 irradiates a measurement space M with a measurement light LM including a wavelength range interacting with 0-valent mercury. The detector 533 detects the measurement light LM passing through the measurement space M. The operation controller 55 calculates information on the ratio of 0-valent mercury and 2-valent mercury in the measurement target gas on the basis of a time change pattern showing the change with time of the intensity of detecting the measurement light LM when the measurement target gas exists in the measurement space M.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an analyzer for calculating information relating to the presence of mercury, a method for removing mercury contained in exhaust gas, and an incinerator system including an incinerator for burning garbage.

Conventionally, an incinerator that incinerates garbage, a measuring device that detects mercury contained in exhaust gas from the incinerator, and a mercury removal device that introduces a substance that removes mercury (for example, activated carbon) into the flue of the exhaust gas An incinerator system is known.
As a measuring device for mercury in exhaust gas, for example, a measuring device disclosed in Patent Document 1 is known. In this measuring apparatus, mercury is detected using the characteristic that zerovalent mercury absorbs ultraviolet light.

JP 2007-268426 A

  In exhaust gas, mercury is known to exist in the form of zero-valent mercury, divalent mercury, and / or particulate mercury, but the exhaust gas is measured with the above measuring device without any treatment. Even so, it was thought that information on the presence of divalent mercury could not be obtained. This is because divalent mercury does not interact with ultraviolet light (for example, it does not absorb or fluoresce light).

  An object of the present invention is to obtain information related to the existence ratio of zero-valent mercury and divalent mercury in exhaust gas only by detecting zero-valent mercury contained in the exhaust gas.

An analyzer according to an aspect of the present invention includes a light source, a detector, and a calculation unit. The light source irradiates the measurement space with measurement light including at least a wavelength range that interacts with zerovalent mercury. The detector detects the measurement light that has passed through the measurement space. The calculation unit is a zero valence included in the measurement target gas based on a temporal change pattern representing a temporal change in the detection intensity of the measurement light detected by the detector when the measurement target gas exists in the measurement space. Calculate information related to the presence of mercury and divalent mercury.
As a result, information on the abundance ratio of zero-valent mercury and divalent mercury in the measurement target gas can be obtained only by measuring the interaction between the zero-valent mercury contained in the measurement target gas and the measurement light as the detection intensity. it can.

  The time change pattern may include a first pattern in which the detection intensity varies greatly in a short time. Thereby, information related to the existence ratio of zero-valent mercury and divalent mercury can be obtained from a sudden change in detection intensity.

  If it determines with a time change pattern being a 1st pattern, a calculating part may output the 1st signal which shows that the ratio of the zerovalent mercury contained in measurement object gas is high. Thereby, it can notify outside that the ratio of zerovalent mercury in a measuring object gas is high.

  The time change pattern may include a second pattern in which a state where the change amount of the detected intensity from the intensity when no zero-valent mercury is detected is not less than the first threshold and not more than the second threshold continues for a predetermined period. As a result, from the time variation of the detected intensity in which the amount of change in the detected intensity from the intensity when no zero-valent mercury is detected is not less than the first threshold and not more than the second threshold, the zero-valent mercury and 2 Information related to the presence of valence mercury can be obtained.

  If it determines with a time change pattern being a 2nd pattern, a calculating part may output the 2nd signal which shows that the ratio of the bivalent mercury contained in measurement object gas is high. Thereby, it can notify outside that the ratio of divalent mercury in measurement object gas is high.

A probe housing that has a filter for collecting dust contained in the measurement target gas and that takes the measurement target gas from which dust has been removed into the measurement space, and dust collected by the filter by injecting blowback gas into the filter And a blow-back device for removing water.
Thereby, the measurement object gas containing almost no dust can be introduced into the measurement space at high speed, and zero-valent mercury contained in the measurement object gas can be detected at high speed. The analyzer can also be used in an environment where the measurement target gas contains a large amount of dust.

A first flow path for introducing the measurement target gas into the measurement space, and a second flow path having one end branched from the first flow path and the other end connected to the measurement space via a scrubber that removes mercury from the measurement target gas And a switching unit that alternately switches between the first flow path and the second flow path.
At this time, the calculation unit removes mercury from the measurement target gas by passing through the second flow path and the measurement intensity that is the intensity of the measurement light when the measurement target gas is introduced into the measurement space from the first flow path. The detection intensity is calculated based on the difference between the measured reference gas and the reference intensity that is the intensity of the measurement light when the reference gas is introduced into the measurement space.
This eliminates the influence of interference components that interact with the measurement light in the wavelength range that interacts with the zero-valent mercury, thereby detecting only the interaction of the zero-valent mercury with the measurement light and increasing the detection intensity of the zero-valent mercury. It can be calculated accurately.

  The measurement target gas may be a gas that has not undergone a reduction process that converts divalent mercury contained in the measurement target gas into zero-valent mercury. Thereby, zerovalent mercury can be detected at high speed.

The calculation unit calculates the detected concentration of zero-valent mercury based on the detected intensity, and based on the concentration-time change pattern representing the temporal change in the detected concentration, the zero-valent mercury and divalent contained in the measurement target gas. Information related to the abundance of mercury may be calculated.
Thereby, information related to the abundance ratio of zero-valent mercury and divalent mercury contained in the measurement target gas can be calculated from information based on the abundance of zero-valent mercury, which is the detected concentration of zero-valent mercury.

The mercury removal method according to another aspect of the present invention includes the following steps.
A step of irradiating the measurement space with measurement light including at least a wavelength range that interacts with zero-valent mercury.
A step of detecting measurement light that has passed through the measurement space.
◎ Based on the temporal change pattern that represents the temporal change in the detection intensity of the measurement light detected when the measurement target gas exists in the measurement space, the zero-valent mercury and divalent mercury contained in the measurement target gas Calculating information related to the existence ratio.
A step of determining a mercury removal method based on information relating to the existence ratio of zero-valent mercury and divalent mercury.
As a result, only by measuring the interaction between the zero-valent mercury contained in the measurement target gas and the measurement light as the detection intensity, information on the abundance ratio of zero-valent mercury and divalent mercury in the measurement target gas is obtained. Mercury removal method can be determined.

The step of calculating information related to the existence ratio of zero-valent mercury and divalent mercury is included in the measurement target gas when it is determined that the time change pattern is the first pattern in which the detection intensity greatly varies in a short time. A step of outputting a first signal indicating that the ratio of zero-valent mercury is high, and a change amount of detected intensity from the intensity when the time change pattern does not detect zero-valent mercury is not less than the first threshold and not more than the second threshold. If it is determined that the certain state is the second pattern that continues for a predetermined period, a step of outputting a second signal indicating that the ratio of divalent mercury contained in the measurement target gas is high may be included.
Thereby, information about whether the ratio of zero-valent mercury or the ratio of divalent mercury is large in the measurement target gas can be notified to the outside.

An incinerator system according to still another aspect of the present invention includes an incinerator, a mercury removal device, and an analysis device. Incinerators incinerate garbage. The mercury removal device removes mercury contained in the exhaust gas discharged from the incinerator. The analyzer samples and analyzes the exhaust gas.
The analyzer includes a light source, a detector, and a calculation unit. The light source irradiates the measurement space with measurement light including at least a wavelength range that interacts with zerovalent mercury. The detector detects the measurement light that has passed through the measurement space. The calculation unit is configured to detect zero-valent mercury and divalent contained in the exhaust gas based on a temporal change pattern representing a temporal change in the detection intensity of the measurement light detected by the detector when the exhaust gas exists in the measurement space. Calculate information related to the presence of mercury.
Thereby, information about the abundance ratio of zero-valent mercury and divalent mercury in the exhaust gas can be obtained only by measuring the interaction between the zero-valent mercury contained in the exhaust gas and the measurement light as the detection intensity.

When the calculation unit determines that the time change pattern is the first pattern in which the detection intensity greatly fluctuates in a short time, the mercury removal device outputs a first signal indicating that the ratio of zero-valent mercury contained in the measurement target gas is high. And the time change pattern is determined to be the second pattern in which the amount of change in the detected intensity from the intensity when no zero-valent mercury is detected is not less than the first threshold and not more than the second threshold continues for a predetermined period. Then, you may output the 2nd signal which shows that the ratio of the bivalent mercury contained in measurement object gas is high to a mercury removal apparatus.
Thereby, the analysis apparatus can notify the mercury removal apparatus of information about whether the ratio of zero-valent mercury or the ratio of divalent mercury is large in the exhaust gas.

A program according to still another aspect of the present invention is a program for causing a computer to execute the following steps.
A step of irradiating the measurement space with measurement light including at least a wavelength range that interacts with zero-valent mercury.
A step of detecting the measurement light that has passed through the measurement space.
◎ Existence of zero-valent mercury and divalent mercury contained in the measurement target gas based on the temporal change pattern representing the temporal change in the detection intensity of the measurement light detected when the measurement target gas exists in the measurement space Calculating information related to the percentage;

  Information relating to the proportion of zero-valent mercury and divalent mercury in the exhaust gas can be obtained only by detecting zero-valent mercury contained in the exhaust gas.

The figure which shows the structure of an incinerator system. The figure which shows the structure of a 1st analyzer. The figure which shows an example of the time change pattern of the detection density | concentration of zerovalent mercury. The flowchart which shows the removal operation | movement of mercury in an incinerator system. The figure which shows typically the determination method of the density time change pattern based on the rising speed of detection density. The figure which shows typically the determination method of the density time change pattern based on the maximum value of detected density. The figure which shows typically the determination method of the density time change pattern based on time until detection density rises from a predetermined value and returns.

1. First Embodiment (1) Incinerator System Hereinafter, an incinerator system 100 according to a first embodiment will be described with reference to FIG. FIG. 1 is a diagram showing a configuration of an incinerator system. The incinerator system 100 is a system for incinerating waste such as waste, and includes a waste incineration facility 1, a system calculation control unit 3, and a first analyzer 5.
In addition, as shown in FIG. 1, the incinerator system 100 includes a second analyzer 7, a third analyzer 9, and a second exhaust pipe R 2 that connects the bag filter 12 (described later) and the chimney 14. May be further provided. With these analyzers, mercury in the exhaust gas discharged from the bag filter 12 and mercury in the exhaust gas immediately before being discharged from the chimney 14 can be analyzed.

(2) Waste incineration equipment The waste incineration equipment 1 is equipment for discharging exhaust gas generated by incineration of waste. The waste incineration facility 1 includes an incinerator 11, a first mercury removing device 13, and a bag filter 12. The incinerator 11 is a furnace for incinerating waste such as waste. The incinerator 11 is connected to a first exhaust gas pipe R1 for discharging exhaust gas generated by incineration of garbage. The bag filter 12 is connected to the opposite end of the first exhaust gas line R1 to the side to which the incinerator 11 is connected, removes dust from the exhaust gas, and passes the exhaust gas from which the dust has been removed via the second exhaust gas line R2. And discharged from the chimney 14 to the outside.

  The first mercury removing device 13 is connected immediately before the bag filter 12 in the first exhaust gas line R1, introduces a mercury removing agent (for example, activated carbon, chelating agent) into the first exhaust gas line R1, 12 is an apparatus for removing mercury in the exhaust gas immediately before entering 12. The first mercury removing device 13 determines how and what type of mercury removing agent is introduced based on the information related to the existence ratio of zero-valent mercury and divalent mercury calculated in the first analyzer 5. select.

  By having the above configuration, the waste incineration facility 1 selects an appropriate mercury removal method based on the analysis result of the first analyzer 5 to efficiently remove mercury from the exhaust gas, and remove mercury and dust. The exhausted gas can be discharged from the chimney 14 to the outside.

In one embodiment, the waste incineration facility 1 may have a second mercury removing device 15 in the middle of the second exhaust gas pipe R2. The second mercury removing device 15 is a device that removes mercury in the exhaust gas by passing the exhaust gas through water containing activated carbon or ammonia and / or a chelating agent, for example. By having the second mercury removing device 15, mercury in the exhaust gas from the incinerator 11 can be more reliably removed.
In one embodiment, the waste incineration facility 1 may have a temperature reducing tower 16 immediately before the first mercury removing device 13 in the first exhaust gas pipe line R1. By having the temperature reducing tower 16, the temperature of the exhaust gas from the incinerator 11 can be reduced.

(3) System Operation Control Unit The system operation control unit 3 is a system for controlling the waste incineration facility 1 having a CPU, a RAM, a ROM, other storage devices, various interfaces, an operation panel, and the like. The system calculation control unit 3 controls each component of the waste incineration facility 1.

(4) First analyzer (4-1) Overview of first analyzer The first analyzer 5 is configured to detect zero-valent mercury contained in exhaust gas (an example of measurement target gas) sampled from the first exhaust gas pipe R1. It is an apparatus for measuring the concentration using the property that zerovalent mercury absorbs ultraviolet light. Specifically, as shown in FIG. 2, the first analyzer 5 includes a probe unit 51, an analyzer unit 53, and a calculation control unit 55. FIG. 2 is a diagram illustrating the configuration of the first analyzer.

(4-2) Probe Unit The probe unit 51 samples the exhaust gas discharged from the incinerator 11, for example, immediately before the bag filter 12 in the first exhaust gas pipe R <b> 1 and introduces it into the analyzer unit 53. The probe unit 51 includes a probe housing 511, a probe 513, a primary filter 515, and a blowback pipe 517.
The probe housing 511 has an internal space in which one end is connected to the first pump P1 and the other end is connected to a probe 513 that is a hollow tube. The primary filter 515 is disposed on the side close to the probe 513 in the internal space of the probe housing 511.

  When the first pump P1 is operated in the above configuration, the exhaust gas flowing through the first exhaust gas pipe R1 by the suction passes through the probe 513 and the primary filter 515 and is taken into the internal space of the probe housing 511. It is. By passing the exhaust gas through the primary filter 515, fine particles such as dust can be removed from the exhaust gas, and exhaust gas containing almost no dust (fine particles) can be taken into the internal space and introduced into the analyzer unit 53.

The blowback pipe 517 is a hollow pipe member having one end disposed immediately before the primary filter 515 and the other end connected to a blowback gas supply device GS1 (for example, a supply device such as air or nitrogen gas).
When blowback gas (for example, air, nitrogen gas, etc.) is supplied from the blowback gas supply device GS1, the blowback pipe 517 injects blowback gas into the primary filter 515 and is collected by the primary filter 515. Remove fine particles such as dust.
The blowback pipe 517 and the blowback gas supply device GS1 are collectively referred to as a “blowback device”.

  By having the blowback device, the primary filter 515 can be prevented from being clogged, and the exhaust gas sampling flow rate can be maintained at a high level. As a result, the first analyzer 5 can introduce exhaust gas containing almost no dust into the measurement space M at high speed, and can detect zero-valent mercury in the exhaust gas at high speed.

  Since the probe unit 51 has the above-described configuration, the first analyzer 5 can be used in an environment where exhaust gas containing a lot of dust flows, such as exhaust gas discharged from the incinerator 11 (before passing through the bag filter 12). Can be used.

In the present embodiment, the probe unit 51 samples the exhaust gas before the bag filter 12. However, for example, the probe unit 51 may be attached to the incinerator 11 and the exhaust gas in the incinerator 11 may be sampled.
When the garbage incineration facility 1 has the temperature reducing tower 16, the probe unit 51 may be attached between the incinerator 11 and the temperature reducing tower 16 in the first exhaust gas pipe R1, as shown in FIG. It may be attached between the temperature reducing tower 16 and the bag filter 12.

(4-3) Analyzer Unit The analyzer unit 53 is a device for detecting mercury in the sampled exhaust gas. Specifically, the analyzer unit 53 mainly includes a cell 531, a light source 532, and a detector 533. The cell 531 is a member having a measurement space M and two gas ports that can flow therethrough. One gas port of the cell 531 is connected to a gas port b1 of a first switching valve 534 (described later), and the other gas port is connected to an exhaust pump EP.

With the above configuration, the first exhaust gas sampled by the first pump P1 and the second pump P2 disposed between the first pump P1 and the cell 531 in the first flow path FR1 extending from the probe unit 51 is the first. It is introduced into the measurement space M through the flow path FR1. Thereafter, after the exhaust gas exists in the measurement space M for a predetermined time, it is discharged from the exhaust port E to the outside by suction of the exhaust pump EP. In order to introduce exhaust gas into the measurement space M at a constant flow rate, the pressure in the measurement space M is adjusted to a predetermined constant pressure.
In the present embodiment, two pumps, a first pump P1 and a second pump P2, are provided to increase the sampling flow rate of the exhaust gas. Instead, exhaust gas may be sampled from the probe unit 51 by suction of a single pump that can suck exhaust gas at a high sampling flow rate.

  A first scrubber SC1 (for example, activated carbon) for removing mercury contained in the exhaust gas discharged from the measurement space M is attached between the exhaust side of the exhaust pump EP and the exhaust port E.

  The light source 532 is attached to one end of the cell 531 and has a measurement space LM including at least a wavelength range (for example, a wavelength in a predetermined range centered on 253 nm) absorbed by zero-valent mercury (an example of interaction). For example, a mercury lamp, a xenon lamp, an LED that can generate light in the ultraviolet region, or a laser diode (LD) that irradiates M.

  The detector 533 is attached to the cell 531 so as to face the light source 532, and detects the measurement light LM that has passed through the measurement space M. For example, the detector 533 is a photodiode or a photomultiplier tube that can detect light in the ultraviolet region.

The analyzer unit 53 of the present embodiment further includes a first switching valve 534 (an example of a switching unit) having three gas ports a1, b1, and c1, one end branched from the first flow path FR1, and the other end. And a second flow path FR2 connected to the gas port c1 of the first switching valve.
The gas port a1 of the first switching valve 534 is connected to the first flow path, and the gas port b1 is connected to the cell 531 (measurement space M). The first switching valve 534 switches between the gas port a1 and the gas port b1 or the gas port c1 and the gas port b1 according to a command from the arithmetic control unit 55.

The second flow path FR2 has a second scrubber SC2 having one end connected to the side branched from the first flow path FR1 and the other end connected to the gas port c1. The second scrubber SC2 is, for example, a column filled with diatomaceous earth impregnated with gold. Also, the second scrubber SC2 is heated to a predetermined temperature so as not to capture interference components other than zero-valent mercury (eg, SO ₂ , hydrocarbons, etc.) that interact with light in the wavelength range absorbed by zero-valent mercury. I have to.

When the gas port c1 and the gas port b1 are circulated by the first switching valve 534, the exhaust gas passes through the second scrubber SC2 from the second flow path FR2, and enters the measurement space M through the gas port c1 and the gas port b1. be introduced.
The exhaust gas introduced into the measurement space M via the second flow path FR2 is in a state in which interference components contained in the exhaust gas before passing through the second scrubber SC2 other than mercury remain. Therefore, the exhaust gas that has passed through the second flow path FR2 is referred to as “reference gas”, which is a gas from which only mercury has been removed.

  On the other hand, when the gas port a1 and the gas port b1 are circulated, the exhaust gas is introduced into the measurement space M without passing through the scrubber.

  When the mercury is detected by the analyzer unit 53 having the second flow path FR2, the first switching valve 534 circulates the gas port a1 and the gas port b1 at a predetermined cycle (for example, 1 Hz), By switching between the gas port c1 and the gas port b1, the exhaust gas and the reference gas are alternately introduced into the measurement space M (fluid modulation method).

In one embodiment, the analyzer unit 53 branches from the outlet side of the second pump P2 of the first flow path FR1 and the flow rate adjusting valve 535 (for example, a needle valve) that adjusts the sampling flow rate of the exhaust gas from the probe unit 51. And a third flow path FR3 that bypasses the cell 531 and is connected to the exhaust port E.
The sampling flow rate of the exhaust gas from the probe unit 51 can be adjusted by the flow rate adjusting valve 535. Further, the third flow path FR3 can introduce a part of the sampled exhaust gas into the third flow path FR3 to bypass the cell 531. As a result, it is possible to avoid introducing excessive exhaust gas into the cell 531 while sampling the exhaust gas at high speed.

  The third flow path FR3 has a third scrubber SC3 on the side close to the exhaust port E. Thereby, mercury contained in the exhaust gas bypassing the cell 531 can be removed before discharge. Further, the third flow path FR3 may have a flow meter FM in the vicinity of the branch point from the first flow path FR1. Thereby, the flow volume of the exhaust gas which bypasses the cell 531 can be monitored.

  In one embodiment, the analyzer unit 53 has three gas ports a2, b2, and c2, and allows the gas port a2 and the gas port b2 to circulate, or whether the gas port c2 and the gas port b2 circulate. A second switching valve 536 for switching between and a calibration gas supply device GS2 connected to the gas port c2 may be included. The calibration of the analyzer unit 53 can be executed by introducing the calibration gas from the calibration gas supply device GS2 in a state where the second switching valve 536 opens the gas port c2 and the gas port b2.

  In one embodiment, the analyzer unit 53 may arrange a filter 537 between the cell 531 of the first flow path FR1 and the second pump P2. Thereby, particulates such as dust that could not be captured by the primary filter 515 can be further captured by the filter 537, and more dust-free exhaust gas can be introduced into the measurement space M.

(4-4) Arithmetic Control Unit The arithmetic control unit 55 (an example of the arithmetic unit) includes a CPU, a RAM, a ROM, other storage devices, various interfaces, etc., and controls each component of the first analyzer 5; This is a computer system that processes signals input from the analyzer unit 53.
As information processing of the signal input from the analyzer unit 53, the arithmetic control unit 55 introduces the exhaust gas into the measurement space M when the exhaust gas and the reference gas are alternately introduced into the measurement space M at a predetermined cycle. The difference between the measurement intensity that is the intensity of the measurement light acquired when the reference gas is introduced and the reference intensity that is the intensity of the measurement light LM acquired when the reference gas is introduced into the measurement space M (for example, these two The detection intensity of the measurement light LM affected by the presence of zero-valent mercury is calculated based on the signal difference or ratio. Thereafter, the detection concentration of zero-valent mercury is calculated based on the detection intensity. Thereby, the influence on the detection concentration (detection intensity of the measurement light LM) due to the interference component contained in the exhaust gas is removed, and only the interaction (absorption) of zero-valent mercury with the measurement light LM can be detected. As a result, the detected concentration of zero-valent mercury can be calculated with high accuracy.

In addition, the arithmetic control unit 55 calculates information related to the existence ratio of zero-valent mercury and divalent mercury contained in the exhaust gas based on the concentration time variation pattern of the detected zero-valent mercury concentration. A method of calculating the information from the concentration time change pattern of the zero-valent mercury detection concentration will be described in detail later.
Note that various types of information processing executed in the arithmetic control unit 55 may be realized by a program stored in a RAM, a ROM, and / or a storage device.

As described above, in the first analyzer 5 of the present embodiment, no scrubber is provided in the first flow path FR1 from the probe unit 51. That is, the exhaust gas introduced into the measurement space M for detecting mercury does not undergo a reduction process for converting divalent mercury contained in the exhaust gas into zero-valent mercury.
By not providing the scrubber in the first flow path FR1 (and / or the probe unit 51), the flow rate when introducing the exhaust gas into the measurement space M can be increased. As a result, zero-valent mercury in exhaust gas can be detected at high speed.

  In one embodiment, the first analyzer 5 may be provided with a water removal unit 57 in the first flow path FR1, as shown in FIG. The moisture removing unit 57 is constituted by a drain separator and an electronic cooler (both not shown), and can remove moisture contained in the exhaust gas and introduce it into the analyzer unit 53.

(5) Concentration Time Change Pattern of Detected Concentration of Zero-valent Mercury Hereinafter, the results of detecting zero-valent mercury by sampling the exhaust gas from the first exhaust gas pipe R1 with the first analyzer 5 will be described.
As a result of continuously sampling the exhaust gas from the first exhaust gas pipe R1 for a predetermined time and measuring the detected concentration of zero-valent mercury in the exhaust gas in the first analyzer 5 described above, detection of zero-valent mercury It was found that the density shows two types of characteristic temporal changes (density time change patterns) as shown in FIG. FIG. 3 is a diagram illustrating an example of a temporal change pattern of the detected concentration of zero-valent mercury.
As shown in FIG. 3, the concentration time change pattern in the present embodiment is a change with time in the detected concentration of zero-valent mercury that occurs within a predetermined time range (for example, within a time range of several seconds to several tens of minutes). is there.

  The first type is a pattern (referred to as a first pattern) in which the detected density greatly fluctuates in a short time, as shown in FIG. As a result of continuously measuring the concentration of other components in the exhaust gas together with the concentration of zero-valent mercury, when the first pattern was generated, a sudden change in the concentration of carbon monoxide was also observed. From this, the 1st pattern has shown that the incinerator 11 is in an incomplete combustion state.

  When exhaust gas is in a reducing atmosphere (a state containing a reducing component) due to incomplete combustion in the incinerator 11, divalent mercury (mercury compound) is easily reduced to zero-valent mercury and also suppresses the generation of divalent mercury. Is done. In general, the ratio of zero-valent mercury and divalent mercury in the exhaust gas discharged from the incinerator 11 is larger than the ratio of zero-valent mercury (for example, zero-valent mercury: divalent mercury = 1). 9) is known, but the ratio of zero-valent mercury increases in the exhaust gas in a reducing atmosphere (for example, zero-valent mercury: divalent mercury = 1: about 1: 1). Therefore, the first pattern is an index indicating that the ratio of zero-valent mercury in the exhaust gas is high.

The second type is a pattern (referred to as a second pattern) in which the detected density exceeds a predetermined threshold and remains small for a predetermined period, as shown in FIG. When the second pattern was generated, the generation of carbon monoxide was not observed. Therefore, the second pattern indicates that the incinerator 11 is in a complete combustion state, and the exhaust gas has an oxidizing atmosphere (for example, contains a large amount of SO ₂ and HCl).
In the exhaust gas in an oxidizing atmosphere, the existence ratio of zero-valent mercury and divalent mercury in the exhaust gas is such that the generally known ratio of divalent mercury is larger than the ratio of zero-valent mercury (for example, zero-valent mercury). Mercury: divalent mercury = 1: 9). Therefore, the second pattern is an index indicating that the ratio of divalent mercury in the exhaust gas is high.

  Thus, the presence of zero-valent mercury and divalent mercury contained in the exhaust gas can be detected only by detecting the temporal change in the detected concentration of zero-valent mercury (or the absorption intensity of measurement light LM) using the measurement light LM. Information related to the ratio can be obtained. This is the first time that knowledge related to the existence ratio of zero-valent mercury and divalent mercury can be obtained only by detecting zero-valent mercury.

(6) Mercury Removal Operation in Incinerator System Next, the mercury removal operation in the incinerator system 100 using the detection result of zero-valent mercury in the first analyzer will be described with reference to FIG. FIG. 4 is a flowchart showing the mercury removal operation in the incinerator system.
During operation of the waste incineration facility 1, the system calculation control unit 3 instructs the first analyzer 5 to execute mercury analysis at each stage of the waste incineration facility 1.

  Receiving the command, the arithmetic control unit 55 of the first analyzer 5 operates the first pump P1, the second pump P2, and the exhaust pump EP to sample the exhaust gas from the probe unit 51. Thereafter, the arithmetic control unit 55 causes the exhaust gas and the reference gas to be alternately introduced into the measurement space M, and irradiates the measurement space M with the measurement light LM from the light source 532. Further, based on the measurement intensity of the measurement light LM when the exhaust gas exists in the measurement space M and the reference intensity of the measurement light LM when the reference gas exists in the measurement space, the detected concentration of zero-valent mercury is calculated. (Steps S1 to S4).

  Next, the arithmetic control unit 55 confirms the temporal change in the detected concentration of zero-valent mercury every predetermined time range (for example, a time range of several seconds to a few tens of minutes), and the two 0s described above. By determining which pattern the concentration-time change pattern of the detected concentration of valence mercury is, information related to the existence ratio of zero-valent mercury and divalent mercury contained in the exhaust gas is calculated (step S5). For example, the following three methods can be used to determine which pattern is the concentration time change pattern of the detected density.

The first is the rise rate of the detected concentration of zero-valent mercury (for example, data for a predetermined period from the time when a portion surrounded by a dotted line (Cs in FIG. 5A) surrounded by a dotted line of the concentration time change pattern in FIG. 5A is exceeded. This is a method for determining that the first pattern is generated if the slope of the straight line) is equal to or greater than a predetermined value, and that the second pattern is generated if it is smaller than the predetermined value. The rising speed of the detected concentration can be calculated as, for example, the slope of a linear equation obtained by data fitting a plurality of detected concentrations calculated from the past (for example, 5 seconds ago) to the present.
Thereby, it is possible to determine which ratio of zero-valent mercury or divalent mercury is higher at an early stage after the occurrence of zero-valent mercury and / or divalent mercury is detected.

  Second, as shown in FIG. 5B, if the maximum value (peak value) of the detected density is equal to or greater than a predetermined value (Cs1 in FIG. 5B), the first pattern is generated, and the maximum value of the detected density is the predetermined value. This is a method of determining that the second pattern has occurred if it is smaller than the value of, but is greater than or equal to a predetermined threshold (Cs2 in FIG. 5B). The maximum value of the detected concentration can be calculated as, for example, the maximum value of the detected concentration during the period from when the detected concentration has changed to a decreasing tendency (through a certain value) (for example, Cm and Cm ′ in FIG. 5B). ).

  In this case, among the plurality of detection densities from the increasing tendency to the decreasing tendency (through a certain value), the detection density that becomes a noise component (for example, the tendency (the increasing tendency) of the plurality of detection densities) , A decreasing tendency, a tendency to be maintained at a constant value)) is not used for determining whether or not the detected density that is the noise component is the maximum value.

  In one embodiment, the arithmetic control unit 55 constantly monitors the detected density, and the maximum value of the detected density that occurs during the period from when the detected density starts to increase (through a certain value) to the decreasing tendency is a predetermined value. If the value is greater than or equal to the value, it may be determined that the first pattern has occurred, and if the maximum value is smaller than a predetermined value but greater than or equal to a predetermined threshold, it may be determined that the second pattern has occurred.

  The peak value of the first pattern becomes higher than the peak value of the second pattern by determining whether the density time change pattern of the detected density is the first pattern or the second pattern based on the maximum value of the detected density. Using the characteristic (because the proportion of zero-valent mercury increases when the first pattern occurs), it can be determined which proportion of zero-valent mercury or divalent mercury is higher.

Third, as shown in FIG. 5C, after the detected density becomes equal to or higher than a predetermined value (for example, half the maximum value of the detected density) (Ca, Ca ′ in FIG. 5C), it returns to the predetermined value. In this method, it is determined that the first pattern is generated if the time until arrival (t1 and t2 in FIG. 5) is equal to or shorter than a predetermined time, and the second pattern is generated if the time is equal to or longer than the predetermined time.
Thus, it can be determined which ratio of zero-valent mercury or divalent mercury is higher based on the length of the change in the concentration time change pattern.

As a result of the above determination, if it is determined that the concentration time change pattern of the detected concentration of zero-valent mercury is the first pattern (in the case of “first pattern” in step S4), the arithmetic control unit 55 is included in the exhaust gas. A first signal indicating that the ratio of zero-valent mercury is high is output to the first mercury removing device 13 via the system calculation control unit 3 (step S6).
The first mercury removing device 13 that has received the first signal throws, for example, activated carbon impregnated with halogen into the first exhaust gas line R1 in order to more efficiently remove zero-valent mercury in the exhaust gas (step S7). ).

On the other hand, if it is determined that the concentration time change pattern of the detected concentration of zero-valent mercury is the second pattern (in the case of “second pattern” in step S4), the arithmetic control unit 55 determines that the proportion of divalent mercury in the exhaust gas is A second signal indicating high is output to the first mercury removing device 13 (step S8).
The first mercury removing device 13 that has received the second signal throws in more activated carbon into the first exhaust gas pipe R1, for example, in order to more efficiently remove divalent mercury in the exhaust gas (step S9).

  By executing the above steps S1 to S9, the first mercury removing device 13 has a signal (first signal) indicating that the proportion of zero-valent mercury contained in the exhaust gas is high, or the proportion of divalent mercury is high. Whether a removal method that efficiently removes zero-valent mercury or a removal method that efficiently removes divalent mercury is adopted. Can be determined early after occurrence. As a result, mercury can be more reliably removed from the exhaust gas.

  The above steps S1 to S9 are continuously executed while the incinerator system 100 is in operation. Further, when the incinerator system 100 is stopped for maintenance or the like, the execution of the above steps S1 to S9 may be stopped.

2. Other Embodiments Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the scope of the invention. In particular, a plurality of embodiments and modifications described in this specification can be arbitrarily combined as necessary.
(A) For example, zero-valent mercury is not detected by the first analyzer 5 (or a small amount of zero-valent mercury cannot be detected due to the setting range), while 0 is not detected by the second analyzer 7 or the third analyzer 9. If valence mercury is detected, it may be determined that the ratio of divalent mercury is extremely high.

  (B) The first signal and the second signal from the first analyzer 5 may be input to the second mercury removing device 15. Thereby, the second mercury removal device 15 accurately grasps the generation timing of mercury and whether the ratio of zero-valent mercury in exhaust gas is high or high in divalent mercury, and removes necessary mercury as necessary. Agent can be introduced.

  (C) Since zero-valent mercury has ultraviolet fluorescence, the first analyzer 5 (second analyzer 7 and third analyzer 9) detects ultraviolet fluorescence of zero-valent mercury, Zero-valent mercury may be analyzed based on the intensity of the fluorescence.

  (D) For example, the first analyzer 5 is configured to remove mercury in exhaust gas from a high-temperature process plant (for example, a plant having a combustion process, such as an oil refining process) and / or zero-valent mercury and / or 2 You may use also for the purpose of detecting valence mercury at high speed.

  (E) In the first analyzer 5, the arithmetic control unit 55 calculates zero-valent mercury and divalent mercury based on the temporal change pattern of the detection intensity of the measurement light LM without calculating the detected concentration of zero-valent mercury. You may calculate the information relevant to the presence rate of.

In this case, the time change pattern of the detection intensity when the first pattern is obtained as the density time change pattern is either that the detection intensity greatly decreases or increases in a short time. Whether the detection intensity decreases or increases due to detection of zero-valent mercury depends on how to take the difference between the background intensity and the measurement intensity.
On the other hand, the time change pattern of the detected intensity when the second pattern is obtained as the concentration time change pattern is that the change amount of the detected intensity from the intensity when no zero-valent mercury is detected is not less than the first threshold and not more than the second threshold ( That is, a pattern in which a change amount of the detected intensity is within a predetermined range smaller than that in the first pattern) continues for a predetermined period.

  The calculation control unit 55 uses the same method as described in the first embodiment on the basis of the fact that the time change pattern of the detection intensity indicates two types of patterns as described above, and the time change pattern of the detection intensity. Can be determined.

  The calculation control unit 55 calculates the information at a higher speed by calculating information related to the existence ratio of zero-valent mercury and divalent mercury based on the temporal change pattern of the detected intensity without calculating the detection concentration. it can.

  INDUSTRIAL APPLICABILITY The present invention can be widely applied to an analyzer that calculates information on the presence of mercury and an incinerator system that includes an incinerator that burns garbage.

DESCRIPTION OF SYMBOLS 100 Incinerator system 1 Garbage incinerator 11 Incinerator 12 Bag filter 13 1st mercury removal apparatus 14 Chimney 15 2nd mercury removal apparatus 16 Temperature reduction tower 3 System operation control part 5 1st analyzer 51 Probe unit 511 Probe housing 513 Probe 515 Primary filter 517 Blowback pipe GS1 Blowback gas supply device 53 Analyzer unit 531 Cell 532 Light source 533 Detector 534 First switching valve 535 Flow adjustment valve 536 Second switching valve 537 Filter EP Exhaust pump FR1 First flow path FR2 2nd flow path FR3 3rd flow path GS2 Calibration gas supply device LM Measurement light M Measurement space P1 1st pump P2 2nd pump R1 1st exhaust gas pipe R2 2nd exhaust gas pipe SC1 1st scrubber SC2 2nd scrubber SC3 1st 3 scrubber E exhaust port FM flow meter a1 , B1, c1, a2, b2, c2 Gas port 55 Operation control unit 57 Moisture removal unit 7 Second analyzer 9 Third analyzer

Claims (14)

A light source that irradiates the measurement space with measurement light including at least a wavelength range that interacts with zero-valent mercury;
A detector for detecting the measurement light that has passed through the measurement space;
Based on a time change pattern representing a temporal change in the detection intensity of the measurement light detected by the detector when the measurement target gas is present in the measurement space, a zero valence contained in the measurement target gas. A calculation unit for calculating information related to the presence ratio of mercury and divalent mercury;
An analyzer comprising:   The analyzer according to claim 1, wherein the time change pattern includes a first pattern in which the detection intensity varies greatly in a short time.   The said calculating part will output the 1st signal which shows that the ratio of the zerovalent mercury contained in the said measuring object gas is high if it determines with the said time change pattern being the said 1st pattern. Analysis equipment.   The time change pattern includes a second pattern in which a state in which the amount of change in the detected intensity from the intensity when no zero-valent mercury is detected is not less than the first threshold and not more than the second threshold continues for a predetermined period. The analyzer in any one of 1-3.   5. When the time change pattern is determined to be the second pattern, the calculation unit outputs a second signal indicating that the ratio of divalent mercury contained in the measurement target gas is high. Analysis equipment. A probe housing for collecting dust contained in the measurement target gas, and for taking the measurement target gas from which the dust has been removed into the measurement space;
A blowback device that removes the dust collected by the filter by injecting blowback gas into the filter;
The analyzer according to any one of claims 1 to 5, further comprising: A first flow path for introducing the measurement object gas into the measurement space;
A second flow path having one end branched from the first flow path and the other end connected to the measurement space via a scrubber that removes mercury from the measurement target gas;
A switching unit that alternately switches between the first channel and the second channel;
Further comprising
The calculation unit includes a measurement intensity that is an intensity of the measurement light when the measurement target gas is introduced into the measurement space from the first flow path, and the measurement target gas by passing through the second flow path. Calculating the detection intensity based on the difference between the reference gas, which is the intensity of the measurement light when the reference gas from which mercury has been removed is introduced into the measurement space,
The analyzer according to any one of claims 1 to 6.   The analyzer according to claim 1, wherein the measurement target gas is a gas that has not undergone a reduction process that converts divalent mercury contained in the measurement target gas into zero-valent mercury.   The calculation unit calculates a zero-valent mercury detection concentration based on the detection intensity, and based on a concentration time change pattern representing a temporal change in the detection concentration, the zero-valent mercury contained in the measurement target gas. The analyzer according to any one of claims 1 to 8, which calculates information related to the existence ratio of mercury and divalent mercury. Irradiating the measurement space with measurement light including at least a wavelength range that interacts with zero-valent mercury;
Detecting the measurement light that has passed through the measurement space;
Zero-valent mercury and divalent mercury contained in the measurement target gas based on a temporal change pattern representing a temporal change in detection intensity of the measurement light detected when the measurement target gas exists in the measurement space. Calculating information related to the presence of
Determining a mercury removal method based on information related to the abundance ratio of zero-valent mercury and divalent mercury;
A method for removing mercury. Calculating information related to the abundance ratio of the zero-valent mercury and the divalent mercury,
If it is determined that the time change pattern is a first pattern in which the detected intensity varies greatly in a short time, a step of outputting a first signal indicating that the ratio of zero-valent mercury contained in the measurement target gas is high; ,
When it is determined that the time change pattern is a second pattern in which the change amount of the detected intensity from the intensity when no zero-valent mercury is detected is not less than the first threshold and not more than the second threshold continues for a predetermined period. Outputting a second signal indicating that the ratio of divalent mercury contained in the measurement target gas is high;
The method for removing mercury according to claim 10, comprising: An incinerator that incinerates garbage;
A mercury removal device for removing mercury contained in the exhaust gas discharged from the incinerator;
An analyzer for sampling and analyzing the exhaust gas,
The analyzer is
A light source that irradiates the measurement space with measurement light including at least a wavelength range that interacts with zero-valent mercury;
A detector for detecting the measurement light that has passed through the measurement space;
Based on a temporal change pattern representing a temporal change in the detection intensity of the measurement light detected by the detector when the exhaust gas is present in the measurement space, zero-valent mercury contained in the exhaust gas and 2 A calculation unit that calculates information related to the presence ratio of valence mercury,
Having an incinerator system. The computing unit is
If it is determined that the time change pattern is a first pattern in which the detected intensity varies greatly in a short time, a first signal indicating that the proportion of zero-valent mercury contained in the exhaust gas is high is output to the mercury removing device. And
When it is determined that the time change pattern is a second pattern in which the change amount of the detected intensity from the intensity when no zero-valent mercury is detected is not less than the first threshold and not more than the second threshold continues for a predetermined period. Outputting a second signal indicating that the ratio of divalent mercury contained in the exhaust gas is high to the mercury removing device;
The incinerator system according to claim 12. Irradiating the measurement space with measurement light including at least a wavelength range that interacts with zero-valent mercury;
Detecting the measurement light that has passed through the measurement space;
Zero-valent mercury and divalent mercury contained in the measurement target gas based on a temporal change pattern representing a temporal change in detection intensity of the measurement light detected when the measurement target gas exists in the measurement space. Calculating information related to the presence of
A program that causes a computer to execute.

Images