JP3593064B2 - Organic trace component detector - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an apparatus and a method for detecting, for example, organic trace components such as PCBs and dioxins in treated water discharged from a PCB treatment facility.
[0002]
[Background Art]
In recent years, the production and import of PCB (Polychlorinated biphenyl, a general term for chlorinated isomers of biphenyl) has been prohibited because of its strong toxicity. Although production of this PCB began in Japan around 1954, the adverse effects on living organisms and the environment became apparent in the wake of the Kanemi Yusho incident. There was a background.
[0003]
PCB is a biphenyl skeleton in which 1 to 10 chlorine atoms are substituted. There are theoretically 209 types of isomers depending on the number and positions of the substituted chlorine atoms. The body has been identified. In addition, the physical and chemical properties, in vivo stability, and environmental dynamics of these isomers are diverse, and the current situation is that the chemical analysis of PCBs and the manner of environmental pollution are complicated. Furthermore, PCB is one of the persistent organic pollutants, and has properties that it is not easily decomposed in the environment, is fat-soluble, has a high bioconcentration rate, is semi-volatile, and can be moved through the atmosphere. In addition, it is reported that it remains widely in the environment such as water and living things.
As a result, since PCB is extremely stable in the body, it is accumulated in the body and causes chronic poisoning (skin damage, liver damage, etc.), and carcinogenicity and reproductive / developmental toxicity are recognized.
[0004]
Since PCB has been widely used as insulating oil for transformers and capacitors, it is necessary to treat the PCB. The applicant has previously proposed a hydrothermal decomposition apparatus for detoxifying the PCB. (See JP-A-11-253796, JP-A-2000-126588 and others). FIG. 8 shows an example of the outline of this hydrothermal decomposition apparatus.
[0005]
As shown in FIG. 8, the hydrothermal decomposition apparatus 120 includes a cylindrical primary reactor 122 provided with a cyclone separator 121, a pressurizing pump 124 for pressurizing a treatment liquid 123 of PCB, H ₂ O, and NaOH. It is provided with a preheater 125 for preheating the mixed solution, a secondary reactor 126 having a configuration wound with piping, a cooler 127 and a pressure reducing valve 128. Further, in the downstream of the pressure reducing valve 12 8, the gas-liquid separator 129 is disposed active carbon tank 130, the exhaust gas _(CO 2) 131 is discharged from a chimney 132 to the outside, drainage _(H 2 O, NaCl) 133 Is separately treated as necessary. Further, H ₂ O and NaOH are introduced into the piping 134 of the PCB that becomes the processing liquid 123. Further, the pipe 135 of the oxygen is directly connected to the primary reactor 12 2.
[0006]
In the above apparatus, the pressure inside the primary reactor 122 is increased to 26 MPa by pressurization by the pressurizing pump 124. Further, the preheater 125 preheats the mixed treatment liquid 123 of PCB, H ₂ O and NaOH to about 300 ° C. Further, oxygen is spouted into the primary reactor 122, and the temperature rises to 380 ° C to 400 ° C due to the internal reaction heat. The cyclone separator 121 separates large Na ₂ CO ₃ crystal particles precipitated in the primary reactor 122 and sends Na ₂ CO ₃ fine particles to the secondary reactor 126. The operation of the cyclone separator 121 prevents the secondary reactor 126 from being blocked. By this stage, the PCB has undergone a dechlorination reaction and an oxidative decomposition reaction, and has been decomposed into NaCl, CO ₂ and H ₂ O. Next, in the cooler 127, the fluid from the secondary reactor 126 is cooled to about 100 ° C., and the pressure is reduced to the atmospheric pressure by the pressure reducing valve 128 in the subsequent stage. Then, the CO ₂ and steam and the treated water are separated by the gas-liquid separator 129, and the CO ₂ and steam pass through the activated carbon tank 130 and are discharged into the environment.
[0007]
By treating a PCB-containing container (for example, a transformer or a condenser) or the like using such a processing device, complete harmlessness is achieved, but it is also important to quickly monitor the PCB concentration in the facility. Conventionally, a method has been adopted in which the PCB is concentrated into a liquid by gas sampling and the concentrated liquid is analyzed. However, since this measurement requires several hours to several tens of hours, rapid monitoring was not possible.
[0008]
However, as a method of measuring a trace amount of PCB in a gas for monitoring, a mass spectrum analyzer combining a multiphoton ionization detector and a time-of-flight type analyzer (Time of Flight Spectroscopy: TOFMAS) has been conventionally proposed. I have.
[0009]
The outline of this conventional analyzer will be described with reference to FIG.
[0010]
As shown in FIG. 9, a sample gas 1 is supplied from a pulse nozzle 2 into a vacuum chamber 3 as a supersonic free jet, and the free jet is cooled by adiabatic expansion. Due to such cooling, a gas whose vibration / rotation level is biased toward the low energy side and whose wavelength selectivity is increased has its ionization efficiency, which efficiently absorbs resonant multiphotons such as the laser 4, increased. The molecules in the ionized gas are accelerated by the accelerating electrode 5, are given an acceleration inversely proportional to the mass, fly in the flight tube 6, are reflected by the reflectron 7, and enter the detector 8. By measuring the time of flight in the flight tube 6, the mass of the molecule or atomic particle can be obtained by calculation, and the PCB concentration of the measurement object can be obtained from the comparison of the signal intensity of the detector 8.
[0011]
Such an apparatus is excellent in principle in that a trace substance can be detected, but has a problem that the detection sensitivity is low because a laser pulse time width uses a nanosecond laser.
Therefore, it is desired to efficiently concentrate the sample gas 1.
[0012]
In addition, PCBs are obtained by substituting a plurality of chlorines with a biphenyl skeleton. There are various isomers depending on the number and position of the substituted chlorines, and the selection of the wavelength of the laser corresponding to each is different. say can not, there is a problem.
[0013]
In view of the above problems, it is an object of the present invention to provide an apparatus and a method for detecting an organic trace component that can perform a quick and highly sensitive analysis when monitoring the concentration of a trace component such as PCB.
[0014]
[Means for Solving the Problems]
A first invention of the present invention for solving the above problems is a sample introduction means for continuously introducing a collected sample into a vacuum chamber, a laser irradiation means for irradiating the introduced sample with laser light and laser ionizing, A converging section for converging the laser-ionized molecules, an ion trap for selectively concentrating the converged molecules, and a time-of-flight mass spectrometer having an ion detector for detecting ions emitted at a constant period are provided. In the organic trace component detection device, the laser light emitted from the laser irradiation means passes through the Raman cell and is separated into a plurality of wavelengths, and the plurality of chlorines are replaced by the separated plurality of wavelengths of laser light. An apparatus for detecting an organic trace component is characterized by simultaneously exciting harmful substances .
[0015]
According to a second invention, in the first invention, there is provided an apparatus for detecting an organic trace component, wherein the Raman cell is a cell in which hydrogen is sealed.
[0016]
According to a third aspect, in the first aspect, the sample introduction means is a capillary column, and the tip of the capillary column faces the ion focusing portion.
[0017]
According to a fourth invention, in the first invention, there is provided an apparatus for detecting an organic trace component, wherein a pulse wavelength of the laser is 280 nm or less.
[0018]
According to a fifth invention, in the first invention, there is provided an apparatus for detecting an organic trace component, wherein a pulse time width of the laser is 500 picoseconds or less.
[0019]
The sixth invention is a detection method for detecting the concentration of an organic halide in a gas, wherein a laser beam is introduced into a vacuum chamber continuously, and is separated into a plurality of wavelengths through a Raman cell. The above introduced sample is irradiated with the laser to simultaneously ionize the harmful substances substituted by a plurality of chlorines , selectively condensing the laser-ionized molecules by an ion trap while converging the molecules, and released from the ion trap at a constant period. An organic halide detection method is characterized in that ions are detected by a time-of-flight mass spectrometer.
[0020]
A seventh aspect of the present invention is the method for detecting an organic halide according to the sixth aspect, wherein the gas is a gas in a processing facility subjected to a PCB decomposition treatment.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described, but the present invention is not limited thereto.
[0022]
[First Embodiment]
FIG. 1 is a schematic diagram of an apparatus for detecting an organic trace component according to the present embodiment. As shown in FIG. 1, an organic trace component detection device 50 according to the present embodiment is a detector that detects the concentration of an organic trace component in wastewater or exhaust gas. and continuously leak out capillary column 54 is a sample introduction means for introducing a molecular beam 53 irradiates a laser beam 55 which has passed through the Raman cell 11 in the molecular beam 53 out leakage above, and the laser irradiation hand stage to laser ionization, laser A converging section 56 composed of a plurality of ion electrodes for converging the ionized molecules, an ion trap 57 for selectively concentrating the converged molecules, and reflecting ions emitted at a constant period by a reflectron 58; And a time-of-flight mass spectrometer 60 provided with an ion detector 59 that detects
[0023]
Then, from the comparison of the signal intensities detected by the detector 59, the PCB concentration of the measurement target can be obtained.
[0024]
The measured PCB concentration may be sent to the monitoring command room, and may be disclosed to the outside by, for example, a monitor device (not shown).
[0025]
By providing the Raman cell 11, as shown in FIG. 2, the wavelength λ ₁ of the laser light 55 emitted from the laser irradiating means is changed to Stokes light ( λ ₁ + M ₁ , λ ₁ + M ₂ ...) And anti-Stokes light. ( Λ ₁ −M ₁ , λ ₁ −M ₂ ...). Thus, a plurality of wavelengths can be obtained with the laser light 55 having one wavelength, and the PCB in which a plurality of chlorines are substituted by a plurality of wavelengths can be simultaneously excited efficiently.
[0026]
As an example of the Raman cell, for example, a gas in which a gas such as N ₂ , H ₂ , or CH ₄ is sealed in the cell at a high pressure (for example, about 50 atm) can be exemplified. Then, light having the following wavelength is output due to the interaction of each molecule. _{N 2: 283nm, H 2:} 301nm, CH 4: 288nm
[0027]
FIG. 3 shows the relationship between the wavelength obtained by passing the laser beam 55 through the Raman cell 11 and the laser beam energy.
[0028]
In addition, as shown in FIG. 4, since the wavelengths are sequentially shifted from a low wavelength to a high wavelength depending on the number of substitutions of chlorine in the PCB, it is possible to use a plurality of wavelengths separated by the laser light passing through the Raman cell 11. Efficient measurement is possible.
[0029]
Here, in the device, the capillary column 54 for introducing the collected sample 51 preferably has a tip facing the ion converging section 56, and specifically, among the electrodes constituting the ion converging section 56. Is preferably flush with the electrode closest to the capillary column, or protrudes to the ion trap side from the electrode.
[0030]
The material of the capillary column is preferably quartz or stainless steel. In the case of stainless steel, control can be performed by applying an electric field by the ion focusing section 56.
[0031]
The capillary column has a hole diameter of 1 mm or less, preferably about 3 mm for a laser. In addition, the shorter the distance from the outlet of the capillary column to the laser irradiation position, the better. However, if the distance is too short, the tip will be damaged by the laser beam. Preferably, the efficiency is improved.
[0032]
The pulse wavelength of the laser beam 55 emitted from the laser irradiating means is preferably 300 nm or less, preferably 280 nm or less, and more preferably about 266 ± 10 nm, as will be described later in Examples. This is because if it exceeds 300 nm, ionization of the organic trace component to be measured is not performed well.
[0033]
Pulse time width of the laser beam 5 5 irradiated et al or the laser irradiation hand stage 500 pico (10 ^-12) seconds or less, and more preferably less pulse laser 200 picoseconds. This is because a laser having a pulse time width of nanoseconds (10 ^-9 ) has a low detection sensitivity and is not preferable.
[0034]
The laser irradiation pulse repetition frequency of the laser light emitted from the hand stage 10MHz or more, particularly preferably preferably a 76 MHz. This is because the ionization efficiency is continuously improved by increasing the pulse repetition frequency.
[0035]
As described above, by reducing the pulse time width of the laser light to 500 picoseconds (10 ⁻¹² ) or less, decomposition of the PCB by the laser light can be suppressed, and the detection sensitivity can be improved.
[0036]
FIG. 5 shows an example in which the wavelength is separated by a Raman cell and the PCB is measured using the apparatus as shown in FIG. Here, the horizontal axis is the flight time (second), and the vertical axis is the ion signal intensity (V).
[0037]
FIGS. 6 (a) and 6 (b) show signals from the ion detector that detected PCB at one wavelength. 6B is an enlarged view of FIG. 6A because the ionization efficiency of the 4-chlorine PCB is poor.
[0038]
Using the above measuring device, for example, the concentration of PCB in the wastewater discharged from the PCB decomposition treatment equipment can be measured quickly and accurately, and the treatment can be monitored based on the measurement result.
[0039]
In the embodiment described above, the PCB as an object to be measured is taken as an example of an organic trace component. However, the present invention is not limited to this. The present invention can also be applied to measurement of dioxins or environmental hormones in wastewater discharged from combustion facilities such as incinerators and boilers.
[0040]
[Second embodiment]
FIG. 7 illustrates a gas monitoring system in a PCB detoxification treatment facility using the above-described measuring device.
As shown in FIG. 7, the PCB detoxification processing system is a harmful substance processing system for detoxifying a processing target on which PCB which is a harmful substance is adhered, contained, or stored. It has one or both of a separating means 1004 for separating the harmful substance 1002 from a container 1003 for storing the substance (for example, PCB) 1002 and a disassembling means 1005 for disassembling the constituents 1001a and 100b constituting the object 1001. A pre-processing means 1006, a core separating means 1007 for separating a core 1001a, which is a constituent material of the object processed in the pre-processing means 1006, into a coil 1001b and an iron core 1001c; Coil separating means 1008 for separating the paper into 1001d and paper / tree 1001e; 00 7 separated in the separated core 1001c dismantling means 1005 the metal container (container body and lid, etc.) 1003 and the cleaning unit 1011 and a copper wire 1001d separated by the coil separator 1008 is washed with a washing solution 1010 And a harmful substance decomposing means 1013 for decomposing one or both of the cleaning waste liquid 1012 after cleaning and the harmful substance 1002 separated by the preprocessing means. There is provided a measurement system 61 provided with an organic trace component detection device 50 for measuring the PCB concentration in the environment and the PCB concentration in the exhaust gas 131.
[0041]
Here, as the harmful substance to be detoxified in the present invention, besides PCB, for example, vinyl chloride sheet, hazardous waste paint, waste fuel, toxic chemical, waste resin, untreated explosive, etc. can be mentioned. It is not limited to these as long as they are harmful substances caused by contamination.
[0042]
Examples of the object to be treated in the present invention include, but are not limited to, transformers and capacitors using PCB as an insulating oil, and storage containers storing paints that are harmful substances. Not something.
[0043]
Also, since conventional in the ballast for fluorescent lamps have PCB is used must be detoxified, in this case, without pretreating the capacitance is small, directly fed to the separation means 100 4 By doing so, it can be detoxified.
[0044]
When the harmful substance is a liquid or the like, the harmful substance is detoxified by directly charging the harmful substance decomposition processing means 1013, and the container in which the harmful substance is stored can be processed by the detoxification processing of the constituent materials. It is necessary to confirm that the liquid after the treatment is 3 ppb or less, which is the PCB discharge standard.
Since the configuration of the harmful substance processing means 1013 is the same as that shown in FIG. 8, the same components are denoted by the same reference numerals and description thereof will be omitted.
[0045]
The measuring system 61 of the present invention monitors the environmental concentration of PCB in the pretreatment means 1006 of the harmful substance treatment system and the PCB emission concentration in the exhaust gas 131 by using the trace amount measuring device 50.
By providing this measurement system, the PCB concentration can be monitored quickly and efficiently. As a result, the decomposition process can be performed while always monitoring whether the PCB process is being performed appropriately, and environmentally friendly measures can be taken.
[0046]
【The invention's effect】
As described above, according to the first aspect of the present invention, a sample introduction unit that continuously introduces a collected sample into a vacuum chamber, a laser irradiation unit that irradiates a laser beam to the introduced sample and performs laser ionization, A converging section for converging the laser-ionized molecules, an ion trap for selectively concentrating the converged molecules, and a time-of-flight mass spectrometer having an ion detector for detecting ions emitted at a constant period are provided. In the organic trace component detection device, the laser light emitted from the laser irradiation means passes through the Raman cell and is separated into a plurality of wavelengths, and the separated plurality of wavelengths of laser light replaces a plurality of chlorines. since the excitation of harmful substances at the same time, by Raman effect, excited simultaneously a plurality of harmful substances in which a plurality of chlorine was replaced by a wavelength (e.g. PCB, etc.) efficiently Can Nau.
[0047]
According to a second aspect, in the first aspect, the Raman cell is a cell in which hydrogen is sealed, so that the Raman effect is exhibited.
[0048]
According to a third invention, in the first invention, the sample introduction means is a capillary column, and the tip of the capillary column faces the ion focusing portion, so that the ionization efficiency is improved.
[0049]
In a fourth aspect based on the first aspect, since the pulse wavelength of the laser is 280 nm or less, ionization of the organic halide is favorably performed.
[0050]
In a fifth aspect based on the first aspect, the detection sensitivity is improved because the pulse time width of the laser is 500 picoseconds or less.
[0051]
A sixth invention is a detection method for detecting the concentration of an organic halide in a gas, wherein a laser beam is introduced into a vacuum chamber continuously and separated into a plurality of wavelengths through a Raman cell. The above introduced sample is irradiated with the sample to simultaneously laser-ionize the harmful substances substituted by a plurality of chlorines , and the laser-ionized molecules are selectively concentrated by an ion trap while being converged, and are released from the ion trap at a constant period. Since ions are detected by the time-of-flight mass spectrometer, harmful substances (eg, PCBs) substituted with a plurality of chlorines at a plurality of wavelengths can be efficiently excited simultaneously by the Raman effect.
[0052]
According to a seventh aspect of the present invention, in the sixth aspect, since the gas is a gas in a processing facility subjected to PCB decomposition treatment, the Raman effect efficiently excites the PCB in which a plurality of chlorines are simultaneously substituted by a plurality of wavelengths. Can do it.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of an apparatus for detecting an organic trace component according to a first embodiment.
FIG. 2 is a diagram illustrating a Raman effect of a laser beam that has passed through a Raman cell.
FIG. 3 is a relationship diagram between laser light wavelength and laser light energy due to the Raman effect.
FIG. 4 is a diagram showing the relationship between the wavelength of 1 to 6 chlorine PCB and the ionization efficiency.
FIG. 5 is a measurement result of a PCB using laser light that has passed through a Raman cell.
FIG. 6 is a measurement result of PCB using laser light without using a Raman cell.
FIG. 7 is a schematic diagram of a PCB detoxification processing system according to a second embodiment;
FIG. 8 is a schematic diagram of a hydrothermal decomposition apparatus.
FIG. 9 is a schematic diagram of a laser measurement device according to the related art.
[Explanation of symbols]
11 Raman cell 50 Organic halide detector 51 Sampling sample 52 Vacuum chamber 53 Leaked molecular beam 54 Capillary column 55 Laser beam 56 Converging unit 57 Ion trap 58 Reflectron 59 Ion detector 60 Time-of-flight mass spectrometer

Claims (7)

A sample introducing means for continuously introducing the collected sample into the vacuum chamber, a laser irradiating means for irradiating the introduced sample with laser light to perform laser ionization, a converging unit for converging the laser ionized molecules, An ion trap for selectively concentrating the molecules, and a time-of-flight mass spectrometer equipped with an ion detector for detecting ions emitted at a constant period, an organic trace component detection device comprising: Irradiated laser light passes through a Raman cell and is separated into multiple wavelengths, and the separated laser light of multiple wavelengths simultaneously excites various isomers of harmful substances substituted with multiple chlorines. Organic trace component detection device. 2. The apparatus for detecting an organic trace component according to claim 1, wherein the Raman cell is a cell filled with hydrogen. 2. The apparatus for detecting an organic trace component according to claim 1, wherein the sample introduction means is a capillary column, and the tip of the sample column faces the ion focusing section. 2. The apparatus for detecting an organic trace component according to claim 1, wherein a pulse wavelength of the laser is 280 nm or less. 2. The apparatus for detecting an organic trace component according to claim 1, wherein a pulse time width of the laser is 500 picoseconds or less. A detection method for detecting the concentration of an organic halide in a gas, wherein a sample is continuously introduced into a vacuum chamber, and a laser beam separated into a plurality of wavelengths through a Raman cell is introduced into the sample. Laser ionizes various isomers of harmful substances substituted with multiple chlorines at the same time, selectively concentrates the ions in the ion trap while converging the laser-ionized molecules, and removes the ions released from the ion trap at regular intervals. A method for detecting an organic halide, which is detected by a time-of-flight mass spectrometer. 7. The method for detecting an organic halide according to claim 6, wherein the gas is a gas in a processing facility that has undergone PCB decomposition processing.

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