JP3626930B2 - Laser measuring apparatus and method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus and method for detecting organic halides such as PCBs and dioxins in a processing facility or environment.
[0002]
[Background]
In recent years, PCBs (polychlorinated biphenyls, a general term for polychlorinated biphenyls: chlorinated isomers of biphenyls) are highly toxic, and their production and import are prohibited. Although this PCB was manufactured in Japan from around 1954, the adverse effects on the living body and the environment became apparent after the Kanemi oil affairs incident. In 1972, instructions for discontinuation of production and collection (duty of storage) were issued by administrative guidance. There is a history that was done.
[0003]
PCB has 1 to 10 chlorine atoms substituted on the biphenyl skeleton, and there are theoretically 209 types of isomers depending on the number and position of substituted chlorines. Currently, there are about 100 or more types of isomers in commercially available PCB products. The body has been confirmed. In addition, since the physical and chemical properties among these isomers, in-vivo stability, and environmental moving bodies are diverse, the chemical analysis of PCBs and the mode of environmental pollution are complicated. Furthermore, PCB is one of the persistent organic pollutants and has the property that it is difficult to be decomposed in the environment, is fat-soluble, has a high bioconcentration rate, and is semi-volatile and can be transferred via the atmosphere. In addition, it has been reported to remain 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 disorder, liver disorder, etc.), and carcinogenicity and reproductive / developmental toxicity are recognized.
[0004]
Since PCB has been widely used as insulating oil for transformers, capacitors, etc., it is necessary to treat PCB, and the present applicant has previously proposed a hydrothermal decomposition apparatus for detoxifying PCB. (See JP-A-11-253796, JP-A-2000-126588, etc.). An example of the outline of this hydrothermal decomposition apparatus is shown in FIG.
[0005]
As shown in FIG. 6, the hydrothermal decomposition apparatus 120 includes a cylindrical primary reactor 122 provided with a cyclone separator 121, a pressurizing pump 124 that pressurizes a treatment liquid 123 of PCB, H ₂ O, and NaOH, a mixture preheater 125 for preheating the, the configuration of the secondary reactor 126 wound pipe is made and a cooler 12 8 and the pressure reducing valve 128. Further, a gas-liquid separator 129 and an activated carbon tank 130 are disposed downstream of the pressure reducing valve 127, exhaust gas (CO ₂ ) 131 is discharged from the chimney 132, and drainage (H ₂ O, NaCl) 133 is Separately, wastewater is treated as necessary.
Further, H ₂ O and NaOH are respectively introduced into the PCB pipe 134 which becomes the treatment 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 in the primary reactor 122 is increased to 26 MPa by pressurization by the pressurizing pump 124. The preheater 125 preheats the mixed processing solution 123 of PCB, H ₂ O, and NaOH to about 300 ° C. Further, oxygen is jetted into the primary reactor 122, and the temperature is raised to 380 ° C. to 400 ° C. by 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, PCB has been dechlorinated and oxidatively decomposed and 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 atmospheric pressure by the subsequent pressure reducing valve 128. Then, by the gas-liquid separator 129 CO ₂ and steam and treated water are separated, CO ₂ and water vapor is discharged through the activated carbon bath 130 into the environment.
[0007]
Although such a processing apparatus is used to process a PCB-containing container (for example, a transformer or a capacitor) to make it completely harmless, it is also important to quickly monitor the PCB concentration in the facility. Conventionally, a method of concentrating PCB into a liquid by gas sampling and analyzing the concentrated liquid has been employed, but since this measurement takes several hours to several tens of hours, rapid monitoring has not been possible.
[0008]
However, as a method for measuring a trace amount of PCB in a gas for monitoring, a mass spectrum analyzer combining a multi-photon ionization detector and a time-of-flight mass spectrometer (TOFMAS) has been proposed. Yes.
An outline of this conventional analyzer will be described with reference to FIG.
[0009]
As shown in FIG. 7, the sample gas 1 is supplied from the pulse nozzle 2 into the vacuum chamber 3 as a supersonic free jet, and the free jet is cooled by adiabatic expansion. By such cooling, a gas whose vibration / rotation level is biased toward the low energy side and wavelength selectivity is increased increases its ionization efficiency of efficiently absorbing resonant multiphotons such as the laser 4. Molecules in the ionized gas are accelerated by the accelerating electrode 5, given an acceleration inversely proportional to the mass, flew in the flight tube 6, reflected by the reflecton 7, and incident on the detector 8. By measuring the time of flight in the flight tube 6, the mass of the particle, which is the molecule or atom, is obtained by calculation, and the PCB concentration to be measured can be obtained from the comparison of the signal intensity of the detector 8.
[0010]
Such an apparatus is excellent in principle in that it can detect a trace amount of substance, but has a problem that detection sensitivity is low because a laser pulse width uses a nanosecond laser.
[0011]
In addition, when the ionization of organic halides is efficiently generated with laser light, the pulse width may be shortened. However, if the pulse width becomes too short, a phenomenon that the sensitivity decreases occurs. In the case of a polymer compound such as PCB in which a plurality of Cl groups are bonded, a laser beam having a long pulse width of 100 ps is good in the case of a low chlorinated PCB, while the ionization efficiency is high in the case of a high chlorinated PCB. Laser light having a short pulse width of 10 ps is considered preferable. Therefore, when all PCB compounds are measured, it is necessary to prepare a laser apparatus having a plurality of pulse widths, which causes a problem that the apparatus becomes large.
[0012]
In view of the above problems, an object of the present invention is to provide an organic halide detection apparatus and method capable of rapid and highly sensitive analysis when monitoring trace components such as PCB concentration in a gas.
[0013]
[Means for Solving the Problems]
A first invention of the present invention that solves the above-described problems includes a sample introduction unit that continuously introduces a collected sample into a vacuum chamber, a laser irradiation unit that irradiates the introduced sample with a laser and performs laser ionization, and a laser. A focusing unit for focusing ionized molecules, an ion trap for selectively concentrating the focused molecules, and a time-of-flight mass spectrometer equipped with an ion detector for detecting ions emitted at a constant period A laser measuring device, wherein the laser light from the laser irradiation means performs multiple reflection irradiation with a three-dimensional laser path between opposing prisms so that the laser light does not overlap in the ionization region , In the above three-dimensional laser path, the laser beam is applied to the prism with respect to the plane formed by the laser beam incident on and reflected by each prism. In laser measuring apparatus characterized by position incident is formed by Yuku displaced vertically.
[0015]
A second invention is the laser measurement apparatus according to the first invention, wherein the sample introduction means is a capillary column, and a tip of the capillary column faces an ion converging part.
[0016]
A third invention is Oite the first, in a laser measuring device, characterized in that said capillary column is a quartz or stainless steel.
[0017]
According to a fourth aspect of the present invention, there is provided the laser measurement apparatus according to the first aspect, wherein the pulse width of the laser irradiated from the laser irradiation unit is picoseconds to several tens of picoseconds.
[0018]
A fifth invention is the laser measurement apparatus according to the first invention, wherein the pulse frequency of the laser emitted from the laser irradiation means is 1 MHz or more.
[0019]
A sixth invention is the laser measurement apparatus according to the fifth invention, wherein the pulse frequency of the laser irradiated from the laser irradiation means is 10 to 200 MHz.
[0020]
According to a seventh aspect of the present invention, in the laser measuring apparatus according to the first aspect, the sample is a gas in a processing facility subjected to PCB decomposition processing.
[0021]
According to an eighth aspect of the invention, a sample to be collected is continuously introduced into a vacuum chamber, and the introduced sample is irradiated with a laser to be laser ionized, and the laser ionized molecules are converged and selectively concentrated with an ion trap. A detection method for detecting a concentration of an organic halide in a gas by detecting ions emitted from an ion trap at a constant period with a time-of-flight mass spectrometer, wherein the laser light from the laser irradiation means is detected in an ionization region. Laser beams are subjected to multiple reflection irradiation in a three-dimensional laser path between opposing prisms so that they do not overlap. The three-dimensional laser path includes a laser beam incident on each prism and a reflected laser beam. characterized with respect to a plane defined, that the laser beam to the prism is formed by the position of incidence next Yuku vertically offset with In the laser measurement method.
[0023]
A ninth invention is an organic halide detection method according to the eighth invention, wherein the collected sample is a gas in a processing facility subjected to PCB decomposition treatment.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, although embodiment of this invention is described, this invention is not limited to this.
[0025]
[First Embodiment]
FIG. 1 is a schematic view of a laser measuring apparatus according to this embodiment. As shown in FIG. 1, a laser measuring apparatus 50 according to the present embodiment includes a capillary column 54 as sample introduction means for continuously leaking a sample 51 into a vacuum chamber 52 and introducing it as a molecular beam 53, and the laser beam 55 is irradiated to leak out molecular beam 53, the laser irradiation unit 5 6 to laser ionization, a converging portion 56 comprising a plurality of ion electrodes for converging molecules laser ionization, selects concentrating the converged molecules An ion trap 57 and a time-of-flight mass spectrometer 60 provided with an ion detector 59 that reflects ions emitted at a constant period by a reflectron 58 and detects the reflected ions are provided. . Then, the concentration of the measurement object can be obtained from the comparison of the signal intensity detected by the detector 59.
In FIG. 1, reference numerals 61 and 62 denote lens windows, and 70 denotes a reflecting mirror.
[0026]
As shown in FIG. 2, the laser beam 55 from the laser irradiation unit 56 is reflected by multiple prism units 71 and 72 facing each other, and is introduced into a sample introduced so that the laser beam does not overlap in the ion region 73. On the other hand, laser irradiation is performed. The prism means 71 uses a plurality of prisms, but is not limited to this.
Thereby, since the pulse laser beam does not collide with the sample, the sample is not decomposed, and the laser ionization efficiency for the sample is improved.
[0027]
3 and 4 show an outline of an optical device that introduces laser light so as not to overlap. 3 is a perspective view, FIG. 4A is a side view thereof, and FIG. 4B is a plan view thereof.
As shown in FIGS. 3 and 4, the optical device is composed of single prisms 74 and 75 facing each other, and by adjusting the incidence of the laser beam 55 to be introduced, reflection that never overlaps can be achieved. In the present embodiment, the reflecting mirror 76 is provided and reflected back so that the sample is further excited a plurality of times.
[0028]
For example, assuming an ionization area of 6 mm using the prism, what is required for an incident laser beam of 10 mJ may be reflected 10 times with a laser with an output of 1 mJ. And you can.
In addition, there is a method of simply multiple reflection of laser light, but if the laser light paths overlap during multiple reflection, the ionized molecules will be irradiated again with laser light, which promotes decomposition of the molecules to be measured. A malfunction occurs.
Therefore, in the present invention, in the case of multiple reflection, it is essential that the laser light paths never overlap.
Examples of the method in which the laser light paths do not overlap include a method using a plurality of prisms and mirrors as shown in FIG. 2, a method of adjusting incident laser light to a pair of opposing prisms, and the like. However, the present invention is not limited to these, and any other technique that prevents laser light from overlapping may be used.
[0029]
Here, for example, when analyzing PCB which is an organic halide, in order to improve the ionization efficiency of low chlorine (2 to 4 chlorine) PCB, the pulse width may be increased. In order to improve the ionization efficiency of high chlorine (5 to 7 chlorine atoms) PCB, the pulse width of the incident laser light may be narrowed.
[0030]
For this reason, reflection lens groups 71A, 71B, 72A, 72B having different L as shown in FIG. 4 are provided, and two types of pulsed laser beams are used, and PCB concentrations from a plurality of types of low chlorine to high chlorine are measured simultaneously. be able to.
[0031]
Here, it is preferable that the capillary column 54 has its tip facing the ion converging part 56. Specifically, the capillary column 54 is flush with the electrode on the most capillary column side among the electrodes constituting the ion converging part 56. It is preferable to protrude from the electrode toward the ion trap.
[0032]
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 converging unit 56.
[0033]
The hole diameter of the capillary column is 1 mm or less, preferably about 3 mm of laser. In addition, the closer the distance from the capillary column outlet to the laser irradiation position is, the better. However, the tip is damaged by the laser beam even if it is too close, so that the ionization is performed to the extent that it is not damaged (for example, about 1 to 2 mm). It is preferable to improve efficiency.
[0034]
The pulse wavelength of the laser light 55 emitted from the laser irradiation means 56 is 300 nm or less, preferably 266 ± 10 nm. This is because when the thickness exceeds 300 nm, ionization of the organic halide to be measured is not satisfactorily performed.
[0035]
It is preferred pulse width of the laser beam 5 5 emitted from the laser irradiation means 56 is a pulse laser picosecond to several tens of picoseconds. This is because a laser having a pulse width of nanosecond (10 ⁻⁹ ) is not preferable because of low detection sensitivity.
[0036]
The pulse frequency of the laser light emitted from the laser irradiation means 56 is preferably 1 MHz or more, particularly preferably 10 to 200 MHz.
This is because if it is less than 1 MHz, ionization cannot be continuously performed and ionization efficiency is lowered, which is not preferable.
[0037]
For example, the gas in the PCB decomposition processing facility can be measured quickly and accurately using the measuring device, and the processing process can be monitored based on the measurement result.
[0038]
[Second Embodiment]
Next, a monitoring system for gas in a PCB detoxification processing facility using the apparatus of the present invention will be described.
[0039]
As shown in FIG. 5, the PCB detoxification treatment system is a hazardous substance treatment system for detoxifying a workpiece to which PCB, which is a hazardous substance, is attached, contained or stored, and is a hazardous substance 1001. One or both of separation means 1004 for separating the harmful substance 1002 from the container 1003 for storing the substance (for example, PCB) 1002 and disassembly means 1005 for disassembling the constituent materials 1001a, b,. Pre-processing means 1006, core separating means 1007 for separating the core 1001a, which is a component constituting the workpiece processed in the pre-processing means 1006, into a coil 1001b and an iron core 1001c, and the separated coil 1001b as copper a coil separator 1008 for separating the line 1001d and paper, wood 1001e, and the core separated metal container separating means 100 7 separate core 1001c and dismantling means 1005 (the container main body and the lid or the like) 1003 Coil separation means Cleaning means 1011 for cleaning the copper wire 1001d separated in 1008 with the cleaning liquid 1010, and hazardous substance decomposition treatment for decomposing one or both of the cleaning waste liquid 1012 after cleaning and the hazardous substance 1002 separated by the pretreatment means And means 1013.
[0040]
Here, examples of harmful substances to be detoxified in the present invention include, in addition to PCB, for example, vinyl chloride sheets, hazardous waste paints, waste fuels, hazardous chemicals, waste resins, untreated explosives, etc. It is not limited to these as long as it is a harmful substance resulting from contamination.
[0041]
Examples of the object to be treated in the present invention include, for example, a transformer or a capacitor using PCB as an insulating oil, a storage container storing a paint that is a harmful substance, etc., but is not limited thereto. It is not a thing.
[0042]
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 It can be detoxified.
[0043]
Further, when the harmful substance is a liquid or the like, it is detoxified by directly putting it into the harmful substance decomposing means 1013, and the stored container can be treated by detoxifying the constituent materials. About the liquid after a process, it is necessary to confirm that it is 3 ppb or less which is the discharge standard of PCB.
In addition, since the structure of the harmful substance processing means 1013 is the same as that shown in FIG. 6, the same code | symbol is attached | subjected to the same structural member and the description is abbreviate | omitted.
[0044]
The measurement system 100 of the present invention monitors the PCB concentration in the exhaust gas 131 purified from the processing means 1013 through the activation tank.
By providing this measurement system, the PCB concentration can be monitored quickly and efficiently. As a result, it is possible to perform decomposition processing while always monitoring whether the work process is properly performed, and it is possible to take measures in consideration of the environment.
[0045]
Therefore, using this measuring device, it is possible to always monitor whether the gas standard is satisfied by analyzing every predetermined time, and when there is an emergency, if the PCB concentration exceeds the discharge standard, For example, exhaust gas can be further purified through an active tank, and only the work procedure can be corrected to prevent external environmental contamination.
[0046]
【The invention's effect】
As described above, according to the present invention, the sample introduction means for continuously introducing the collected sample into the vacuum chamber, the laser irradiation means for irradiating the introduced sample with laser and laser ionizing, and the laser ionization A laser comprising a converging unit for converging molecules, an ion trap for selectively concentrating the converged molecules, and a time-of-flight mass spectrometer equipped with an ion detector for detecting ions emitted at a constant period a measuring apparatus, be one which multiple reflection illuminated by three-dimensional laser path between prism laser light from the laser irradiation means opposed to the laser beam so as not to overlap in the ionization region, the tertiary In the original laser path, the laser beam enters the prism next time with respect to the plane formed by the laser beam incident on each prism and the reflected laser beam. Since the position is formed by Yuku displaced vertically, prevents the sample is degraded, improved laser ionization efficiency for the sample, for example, it is possible to analysis of trace PCB in the gas.
[Brief description of the drawings]
FIG. 1 is a schematic view of an organic halide detector according to an embodiment of the present invention.
FIG. 2 is a schematic diagram of multiple reflection of laser light.
FIG. 3 is a schematic view of an optical device for introducing laser light.
4A is a side view of FIG. 3, and FIG. 4B is a plan view of FIG.
FIG. 5 is a schematic diagram of a PCB detoxification processing system according to the present embodiment.
FIG. 6 is a schematic diagram of a hydrothermal decomposition apparatus.
FIG. 7 is a schematic view of a laser measuring apparatus according to a conventional technique.
[Explanation of symbols]
50 Organic Halide Detection Device 51 Collected Sample 52 Vacuum Chamber 53 Leakage Molecular Beam 54 Capillary Column 55 Laser Light 56 Focusing Portion 57 Ion Trap 58 Reflectron 59 Ion Detector 60 Time-of-Flight Mass Spectrometer 61, 62 Lens Window 70 Reflective mirrors 71 and 72 Prism means 73 Ion regions 74 and 75 Single prism 76 Reflective mirror

Claims (9)

Sample introduction means for continuously introducing the collected sample into the vacuum chamber, laser irradiation means for irradiating the introduced sample with laser and laser ionization, a converging unit for converging the laser ionized molecules, and the converged A laser measuring device comprising an ion trap for selectively concentrating molecules and a time-of-flight mass spectrometer equipped with an ion detector for detecting ions emitted at a constant period, wherein In order to prevent the laser light from overlapping in the ionization region, the laser light is subjected to multiple reflection irradiation with a three-dimensional laser path between the opposing prisms , and the three-dimensional laser path is a laser beam incident on each prism. The position where the laser beam next enters the prism is shifted in the vertical direction with respect to the plane formed by the reflected laser beam. Laser measuring apparatus characterized by being more formed. 2. The laser measurement apparatus according to claim 1, wherein the sample introduction means is a capillary column, and a tip of the capillary column faces an ion converging part. Oite to claim 1, a laser measuring device, characterized in that said capillary column is a quartz or stainless steel. 2. The laser measuring apparatus according to claim 1, wherein a pulse width of the laser irradiated from the laser irradiation unit is picoseconds to several tens of picoseconds. 2. The laser measuring apparatus according to claim 1, wherein a pulse frequency of the laser irradiated from the laser irradiation unit is 1 MHz or more. 6. The laser measuring apparatus according to claim 5, wherein a pulse frequency of the laser irradiated from the laser irradiation means is 10 to 200 MHz. 2. The laser measuring apparatus according to claim 1, wherein the sample is a gas in processing equipment subjected to PCB decomposition processing. The collected sample is continuously introduced into the vacuum chamber, and the introduced sample is irradiated with a laser to be laser ionized, and the laser ionized molecules are converged and selectively condensed with an ion trap, and the sample is periodically collected from the ion trap. A detection method for detecting the concentration of an organic halide in a gas by detecting emitted ions with a time-of-flight mass spectrometer so that the laser light from the laser irradiation means does not overlap in the ionization region. Laser light is subjected to multiple reflection irradiation with a three-dimensional laser path between opposing prisms , and the three-dimensional laser path is directed to a plane formed by the laser light incident on each prism and the reflected laser light. , measuring the laser and wherein the laser beam to the prism is formed by the position of incidence next Yuku vertically offset with Method. 9. The method for detecting an organic halide according to claim 8, wherein the collected sample is a gas in a processing facility subjected to PCB decomposition processing.

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