JP6607447B2 - Method for measuring polychlorinated biphenyl content by fluorescent X-ray - Google Patents

Description

  The present invention simply measures the polychlorinated biphenyl content concentration of polychlorinated biphenyl waste stored in a contaminated polychlorinated biphenyl using fluorescent X-ray, and measures the polychlorinated biphenyl content concentration by fluorescent X-ray. Regarding the method.

  Polychlorinated biphenyls have been used in many fields in the past because of their excellent electrical insulation and chemical stability. On the other hand, after its toxicity became apparent, production was banned, but so far a large amount has already been produced and imported and used in a wide variety of forms. Some products containing polychlorinated biphenyls are still in use today. On the other hand, if the waste is used after being used, the storage company properly stores the waste as specially controlled industrial waste based on the Special Measures Law concerning the promotion of appropriate disposal of polychlorinated biphenyl waste. It is obliged to report every year. Moreover, the law stipulates that the proper disposal of polychlorinated biphenyl waste properly stored by the storage company by March 2027 is required, and prompt processing is required.

In August 2012, a new category of polychlorinated biphenyl waste, low-concentration polychlorinated biphenyl waste, was established by law. Contaminants containing low concentrations of polychlorinated biphenyl
(1) Of the sludge, paper waste, wood waste or fiber waste, the amount of polychlorinated biphenyl applied or soaked in the sludge, paper waste, wood waste or fiber waste is 5,000 per kilogram of sludge, paper waste, wood waste or fiber waste. Less than milligrams,
(2) Among waste plastics, the amount of polychlorinated biphenyl adhered to or enclosed in the waste plastics is 5,000 milligrams or less per kilogram of waste plastics,
(3) Polychlorinated biphenyls that adhere to or are enclosed in metal scrap, ceramic scraps, concrete debris generated by construction, renovation or removal of workpieces, and other unnecessary items similar to this 5,000 milligrams or less per kilogram of the substance attached to metal scraps or encapsulated,
It is determined as such.

  In addition, the measurement method is clearly defined to be measured in accordance with the national guidelines of the measurement method for waste containing low-concentration polychlorinated biphenyl.

  In this way, a new classification of polychlorinated biphenyl waste is required, a part of the polychlorinated biphenyl waste that is properly stored is sampled, and the manufacturer is measured for the low-concentration PCB-containing waste determined by the country. It became necessary to measure by the method. It is necessary to move the sample by means such as sampling the sample for analysis from the sealed container that is properly stored or sending the sample to the analysis maker, and it takes 2-3 weeks for the analysis result to be revealed. It was.

  Therefore, if a certain level of polychlorinated biphenyl waste content of polychlorinated biphenyl waste stored as a primary classification can be measured in a short time by a simple method at the storage location, it will be possible to provide a standard for classification. It is. In addition, for storage operators, the movement of polychlorinated biphenyl waste that should be strictly managed must be notified to the government. If a certain level of concentration can be estimated, the convenience will be high.

  In addition, samples are sampled from polychlorinated biphenyl waste that is properly stored, and the content concentration is accurately analyzed by a measurement method for low-concentration polychlorinated biphenyl-containing waste established by the country by the analysis manufacturer. Based on the analysis result, it can be determined whether or not it is less than 5,000 milligrams, and whether or not it corresponds to a low concentration polychlorinated biphenyl waste.

  In view of the above problems, Patent Document 1 describes that a specimen containing polychlorinated biphenyl is irradiated with X-rays, and the amount of chlorine in the specimen is derived from the intensity of the generated fluorescent X-rays. .

  Patent Document 2 discloses an organic material in which a collected sample is carbonized, an organic halide is extracted from the carbonized sample using n-hexane, and the organic halide in n-hexane is measured by a fluorescent X-ray measurement method. A halide measurement method is described.

JP 2006-118943 A JP 2002-350374 A

  However, the measuring method described in Patent Document 1 uses an image intensifier as a sensor in order to detect the intensity of fluorescent X-rays by detecting the luminance of light of a plurality of colors, and the size of the apparatus is small. It is large and cannot be said to be suitable for storage. Moreover, since the liquid is mainly used as the object to be measured, it is difficult to apply to the solid, and the object to be measured is limited.

  Patent Document 2 relates to an organic halide measuring device that can easily measure the content of polychlorinated biphenyls such as insulating oil such as a transformer. However, in Patent Document 2, after carbonizing the object to be measured, polychlorinated biphenyl in the carbide is extracted using an organic solvent, and the X-ray intensity of chlorine in the extract is measured. Many pretreatment steps such as extraction were required.

  In the present invention, the measurement target is not limited and no pretreatment process is required, and the content of polychlorinated biphenyl in the polychlorinated biphenyl waste stored as the primary classification is reduced in a short time by a simple method at the storage location. The object is to provide a method for measuring the concentration of polychlorinated biphenyl using fluorescent X-rays.

The method for measuring polychlorinated biphenyl-containing concentration by fluorescent X-ray according to one aspect of the present invention is as follows.
Creating a measurement sample by leveling the polychlorinated biphenyl concentration in a specimen containing multiple types of polychlorinated biphenyl isomers;
Irradiating the measurement sample with X-rays from an X-ray source, measuring chlorine-specific fluorescent X-rays generated from the measurement sample with a semiconductor detector, and measuring the chlorine concentration;
Among the measurement samples, the chlorine concentration measured by the fluorescent X-ray measurement and the polychlorinated biphenyl concentration measured by the GC-MS method for the measurement samples having different chlorine concentrations prepared by the same type of analyte. And confirming the correlation between them, deriving the polychlorinated biphenyl concentration in the measurement sample based on the confirmed correlation data, and measuring the polychlorinated biphenyl-containing concentration,
Only including,
Creating the measurement sample by leveling the polychlorinated biphenyl concentration in the specimen,
Wherein the step of including the dimension of the longest portion of the subject to create the measurement sample as is miniaturized becomes 0.5mm or less.

According to another aspect of the present invention, the method for measuring a polychlorinated biphenyl-containing concentration by fluorescent X-rays in the above-described embodiment,
Between the step of measuring the chlorine concentration by measuring the chlorine-specific fluorescent X-ray with the semiconductor detector and the step of deriving the polychlorinated biphenyl concentration and measuring the polychlorinated biphenyl-containing concentration,
Among the measurement samples, the chlorine concentration obtained by the fluorescent X-ray measurement takes a value equal to or higher than a resin determination threshold, and further includes a determination step of determining whether the measurement sample is a resin,
In the determination step, when the chlorine concentration obtained by the fluorescent X-ray measurement takes a value equal to or greater than the resin determination threshold, and when the measurement sample is determined to be resin, the polychlorinated biphenyl-containing concentration While performing the PCB content concentration measurement process in the entire measurement sample without performing the process of measuring
A step of measuring the polychlorinated biphenyl-containing concentration when the chlorine concentration obtained by the fluorescent X-ray measurement in the determination step is not a value equal to or higher than the resin determination threshold value or the measurement sample is not a resin. To implement.

According to another aspect of the present invention, there is provided a method for measuring a polychlorinated biphenyl-containing concentration by fluorescent X-ray, in the above-described form,
Deriving the polychlorinated biphenyl concentration and measuring the polychlorinated biphenyl-containing concentration,
Among the measurement samples, the chlorine concentration measured by the fluorescent X-ray measurement and the polychlorinated biphenyl concentration measured by the GC-MS method with respect to the measurement samples prepared by the same type of analyte and having different chlorine concentrations Deriving conversion coefficients by approximating the confirmed correlation with a straight line passing through the origin, and
A step of deriving a polychlorinated biphenyl concentration in the measurement sample by multiplying the chlorine concentration data obtained by the fluorescent X-ray measurement by the conversion coefficient, and measuring a polychlorinated biphenyl-containing concentration,
The step of deriving the polychlorinated biphenyl concentration comprises:
The chlorine concentration obtained by the fluorescent X-ray measurement is X (mg / kg), the polychlorinated biphenyl concentration is Y (mg / kg), and the conversion coefficient is a constant that varies depending on the type of the measurement sample. And when
Based on the following formula (1), the polychlorinated biphenyl concentration in the measurement sample is derived.

  Y = A · X (1)

According to another aspect of the present invention, there is provided a method for measuring a polychlorinated biphenyl-containing concentration by fluorescent X-ray, in the above-described form,
A plastic film is provided as a protective film between the measurement sample and the semiconductor detector,
The plastic film is replaced every time the polychlorinated biphenyl concentration is measured.

  According to the aspect of the present invention, the polychlorinated biphenyl waste of the polychlorinated biphenyl waste stored as the primary division is not limited and the pretreatment process is not necessary, and is stored in the storage place as a primary method. It is possible to provide a method for measuring the content concentration of saponin in a short time.

The flowchart which shows the polychlorinated biphenyl containing concentration measuring method by the fluorescent X ray of one Embodiment of this invention The block diagram of the apparatus for enforcing the polychlorinated biphenyl containing concentration measuring method by fluorescent X-rays of one embodiment of the present invention The graph which shows the correlation with the PCB density | concentration measured using the fluorescent X ray analyzer in Example 1 of this invention, and the PCB density | concentration measured by GC-MS technique The graph which shows the correlation with the PCB density | concentration measured using the fluorescent X ray analyzer in Example 2 of this invention, and the PCB density | concentration measured by GC-MS technique The graph which shows the correlation with the PCB density | concentration measured using the fluorescent X ray analyzer in Example 3 of this invention, and the PCB density | concentration measured by GC-MS technique The graph which shows the correlation of PCB density | concentration measured using the fluorescent X ray analyzer in Example 4 of this invention, and PCB density | concentration measured by the GC-MS method The flowchart which shows the polychlorinated biphenyl containing concentration measuring method by the fluorescent X-ray of other embodiment of this invention

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(One embodiment)
As shown in FIG. 1A, a method for measuring the concentration of polychlorinated biphenyl (hereinafter referred to as PCB) using fluorescent X-rays according to one embodiment of the present invention includes a measurement sample preparation step S01, a measuring instrument parameter adjustment step S02, , X-ray irradiation step S03, fluorescent X-ray measurement step S04, conversion coefficient deriving step S05, and total PCB concentration deriving step S06. Note that the measuring instrument parameter adjustment step S02 is not necessary when the measuring instrument has been adjusted. Further, the conversion coefficient deriving step S05 and the total PCB concentration deriving step S06 can be combined into one step.

  FIG. 1B is a block diagram of an apparatus for carrying out a polychlorinated biphenyl-containing concentration measuring method by fluorescent X-rays. With respect to the measurement sample 1, the chlorine concentration is measured by the measuring device 2 having the X-ray source 3 and the semiconductor detector 4. The control unit 6 is based on the storage unit 7 in which the polychlorinated biphenyl concentration measured by the GC-MS method using the GC-MS device 5 and the chlorine concentration measured by the measuring device 2 are stored, and the information in the storage unit 7. And a calculation unit 8 for performing calculation.

  First, the outline of each process will be described.

  In the first measurement sample creation step S01, the measurement sample 1 is created by leveling the PCB concentration in the specimen containing a plurality of types of PCB (polychlorinated biphenyl) isomers.

  Next, the measuring instrument parameter adjustment step S02 performs parameter adjustment by inputting the parameters of the measuring instrument 2 in consideration of the type of the subject or the measurement conditions.

  Next, in the X-ray irradiation step S03, the measurement sample 1 is irradiated with X-rays from the X-ray source 3.

  Next, in the fluorescent X-ray measurement step S04, as a result of the X-ray irradiation in the step S03, chlorine X-rays generated from the measurement sample 1 are measured by the semiconductor detector 4 to measure the chlorine concentration.

  Next, in the conversion coefficient deriving step S05, the chlorine concentration measured by the fluorescent X-ray measurement on the measurement sample 1 created by the same type of specimen among the measurement samples 1 and having different chlorine concentrations, and GC -Correlation is confirmed with the PCB concentration measured by a precise method such as GC-MS method (ie, gas chromatograph mass spectrometry method) by the MS device 5, and the confirmed correlation data is By approximating with a straight line passing through the origin, a conversion coefficient is derived by the calculation unit 8.

  Next, in the total PCB concentration derivation step S06, the chlorine concentration data obtained by the fluorescent X-ray measurement is multiplied by the conversion coefficient derived in the step S05 by the calculation unit 8, and the measurement including a plurality of types of PCB isomers is performed. The concentration of PCB in the entire sample 1 (hereinafter referred to as total PCB concentration) is derived by the calculation unit 8 to measure the polychlorinated biphenyl-containing concentration by fluorescent X-rays.

  The X-ray irradiation step S03 and the fluorescent X-ray measurement step S04 are collectively referred to as a chlorine concentration detection step.

  Hereinafter, each step will be described in detail.

  In the measurement sample creation step S01, the subject is processed into a form suitable for measurement, and the measurement sample 1 is created.

  In the embodiment of the present invention, as a measurement sample, a PCB contaminant that has not been processed due to difficulty in processing is used as a measurement target (that is, measurement sample 1). In the present specification, the contaminant has the same significance as the waste.

  Contaminants include sludge (soil), wood chips, protective clothing, films, insulators, absorption tubes, etc., each contaminated with PCB.

  In the measurement sample preparation step S01, pretreatment is performed in accordance with each form so that the contaminant that is the measurement sample can be used as the measurement sample 1, and the PCB concentration is leveled. Of these, sludge is generated in the waste liquid treatment process of factories and disposed as industrial waste in the final disposal site. Since sludge containing PCB contaminates the soil, sludge and soil mixed with sludge are It becomes the target of detoxification treatment. In the embodiment of the present invention, sludge, soil, wood chips and the like may be sampled as they are.

  When the contaminant as an example of the subject is protective clothing or films, since PCB is often unevenly distributed in a part of the contaminant, even if the measurement sample is sampled from a part in the original form, The residual PCB concentration of the entire contaminant is not measured, and a sampling error and a measurement error are increased. Therefore, the measurement sample 1 can be created by subdividing, mixing, or dispersing so that the sampling result accurately reflects the concentration of the entire measurement sample (in other words, leveling the polychlorinated biphenyl concentration). preferable. Examples of the fragmentation method include a method using a shredder.

  When the contaminant as an example of the specimen is a solid such as an insulator, the PCB is unevenly distributed on the surface of the solid. For this reason, if the solid matter is measured as it is, the fluorescent X-ray intensity from the PCB unevenly distributed on the surface is measured, so that the entire contaminant contains a high-concentration PCB. Therefore, in order to level the polychlorinated biphenyl concentration, it is preferable to prepare the measurement sample 1 by pulverizing and refining the solid. As for the degree of refinement of the solid matter, the dimension of the longest part is preferably 0.1 mm to 0.5 mm, and more preferably 0.1 mm or less.

  In the measuring instrument parameter adjustment step S02, parameters of the measuring instrument are input to the measuring instrument in consideration of the type of the subject or the measurement conditions. In the present embodiment, a commercially available handheld fluorescent X-ray analyzer is used as an example of the measuring device 2.

  In the chlorine concentration measurement step including the X-ray irradiation step S03 and the fluorescent X-ray measurement step S04, the measuring device 2 is applied to the measurement sample 1 so that the surface of the measurement sample 1 is irradiated with X-rays perpendicularly. It arrange | positions and the measurement sample 1 is irradiated with the X-ray from the X-ray source 3 of the measuring device 2. When X-rays are irradiated, the fluorescent X-rays specific to chlorine generated from the measurement sample 1 are measured by the semiconductor detector 4 of the measuring device 2, and the chlorine concentration is measured by fluorescent X-rays. The measurement result is stored in the storage unit 7 of the control unit 6.

  In the conversion coefficient deriving step S05, the chlorine concentration measured by the fluorescent X-ray measurement using the measuring device 2 for the measurement sample 1 created by the same type of specimen among the measurement samples 1 and having different chlorine concentrations By confirming the correlation with the PCB concentration measured by a precise method such as the GC-MS method and approximating the measurement result with a straight line passing through the origin in the calculation unit 8 of the control unit 6, the conversion coefficient is calculated. Derived by the calculation unit 8. At this time, for example, the PCB concentration is measured for the same measurement sample 1 with the GC-MS device 5 in advance, and the measurement result is stored in the storage unit 7 of the control unit 6.

  In the total PCB concentration deriving step S06, the calculation unit 8 of the control unit 6 multiplies the chlorine concentration (mg / kg) of the measurement sample 1 detected by the measuring device 2 in step S04 by the conversion coefficient obtained in the conversion coefficient deriving step S05. Thus, the total PCB concentration contained in the measurement sample 1 is derived, and the polychlorinated biphenyl-containing concentration is measured.

  That is, as the measured chlorine concentration, if the fluorescent X-ray concentration of chlorine is X (mg / kg), the total PCB concentration is Y (mg / kg), and A is a conversion coefficient, these are the following equations (1) Have the relationship.

Y = A · X (1)
Here, the conversion coefficient A is a constant that varies depending on the type of the subject,
A = (component depending on the type of analyte) × (ratio of molecular weight between PCB and chlorine)
It is represented by two components.

The “component depending on the type of analyte” is, for example, relatively 1 when the soil concentration is measured when the chlorine concentration output by the fluorescent X-ray measurement is a value assuming measurement with respect to SiO ₂ . It takes a close value, and when the material property changes, the value goes away from 1.

“PCB / chlorine molecular weight ratio” means that PCB has 1 to 10 chlorine atoms substituted on the biphenyl skeleton, so the molecular weight varies depending on the number of substituted chlorines. When the number of substituted chlorine is n,
(Molecular weight of PCB)
_{= C 12 H (10-n} ) Cl n = 12 × 12 + 1 × (10-n) + 35.5n
= 154 + 34.5n
Comparing the molecular weight of PCB and chlorine,
(Molecular weight ratio of PCB and chlorine) = (Molecular weight of PCB) / (Total atomic weight of chlorine)
= (154 + 34.5n) /35.5n≈1+4.34/n
When an integer value is entered in n, Table 1 is obtained.

[Conversion factor]
As described above, the conversion coefficient A is an effective constant for directly deriving the weight concentration of the PCB compound present in the measurement sample 1 from the measured fluorescent X-ray concentration of chlorine in the measurement sample 1. Although this conversion coefficient differs for each measurement sample 1, it is in a certain numerical range for the same type of contaminants.

  The conversion coefficient A can be further narrowed down to a numerical value within the optimum range depending on the type of contaminant.

  For example, (1) when the contaminant is sludge (soil), the conversion coefficient A may be 2.4 to 3.0, more preferably 2.6 to 2.8, and 2.7. Is most preferred. As another example, (2) when the contaminant is a film (for example, a polyethylene film), the conversion coefficient A may be 1.7 to 2.4, or 2.0 to 2.1. More preferably, 2.06 is most preferable. As another example, (3) when the contaminant is protective clothing, the conversion coefficient A may be 1.8 to 2.8, and more preferably 2.2 to 2.4. 2.29 is most preferred.

The coefficient of determination R ² of the correlation line indicating the correlation of the measured values is preferably 0.3 or more. If the coefficient of determination ^{R 2} is 0.3 or more, it reliability as data. More preferably, the coefficient of determination ^{R 2} is 0.45 or more, more preferably 0.7 or more, and most preferably 0.9 or more.

(Other embodiments)
As shown in FIG. 6, the method for measuring the concentration of polychlorinated biphenyl (hereinafter referred to as PCB) using fluorescent X-rays according to another embodiment of the present invention includes a measurement sample preparation step S01, a measuring instrument parameter adjustment step S02, , X-ray irradiation step S03, fluorescent X-ray measurement step S04, chlorine-based resin determination step S15, conversion coefficient derivation step S05, total PCB concentration derivation step S06, and PCB-containing concentration measurement step S07 in the entire measurement sample, Is provided. Note that the measuring instrument parameter adjustment step S02 is not necessary when the measuring instrument has been adjusted. Further, the conversion coefficient deriving step S05 and the total PCB concentration deriving step S06 can be combined into one step.

  Since the measurement sample preparation step S01 to the fluorescent X-ray measurement step S04 perform the same operations as those steps of the previous embodiment, the description thereof is omitted.

  In the chlorine-based resin determination step S15, it is determined whether or not the measurement sample 1 may be a chlorine-based resin after the fluorescent X-ray measurement step S04. If it is determined that there is no possibility that the measurement sample 1 is a chlorine-based resin, the conversion coefficient deriving step S05 and the total PCB concentration deriving step S06 are performed as in the previous embodiment. On the other hand, if it is determined that there is a possibility that the measurement sample 1 is a chlorine-based resin, the measurement sample 1 is excluded from the target of the fluorescent X-ray measurement, so that the steps after the conversion coefficient deriving step S05 are not performed. Instead, the PCB-containing concentration measurement step S07 for the entire measurement sample is performed. Here, when the type of the measurement sample 1 is a chlorine-based resin, when the chlorine concentration is measured using fluorescent X-rays, a measured value that is significantly larger than the chlorine concentration derived only from PCB is shown. Utilizing this, it is determined whether or not there is a possibility that the measurement sample 1 is a chlorine-based resin.

For example, the concentration of chlorine in polyvinyl chloride, which is a chlorine-based resin, has the following formula (2) because the molecular formula is C ₂ H ₃ Cl.

Chlorine concentration = atomic weight of Cl / molecular weight (2)
Here, since the atomic weight of Cl is 35.5 and the molecular weight of C ₂ H ₃ Cl is 62.5, the chlorine concentration is 35.5 / 62.5 = 568000 mg / kg (56.8 wt%). It is considered that the chlorine concentration is on the order of several tens of wt%.

  For example, when a chlorine concentration of a certain value (resin determination threshold value) or more, for example, 200,000 mg / kg or more is detected from the measurement sample 1 by the fluorescent X-ray measurement step S04, by visual observation or using infrared spectroscopy. Then, it is determined whether or not the measurement sample 1 is a resin (see chlorine-based resin determination step S15). As a result, when it is determined that the measurement sample 1 is a resin (Yes in the chlorine-based resin determination step S15), it is determined that the measurement sample 1 may be a chlorine-based resin, and is based on fluorescent X-rays. Instead of performing the PCB concentration measurement, instead, the PCB-containing concentration measurement of the measurement sample 1 is performed by a precise method such as GC-MS as the PCB-containing concentration measurement step S07 in the entire measurement sample.

  With such a configuration, when the type of the measurement sample 1 is a chlorine-based resin, the chlorine concentration can be measured accurately rather than using a simple method using fluorescent X-rays. Of polychlorinated biphenyls can be handled properly.

[Example 1]
[Measurement of polychlorinated biphenyl content in ABS resin film with PCB attached]
As an example of the specimen, an ABS resin film is cut to prepare a measurement sample, and each of the polychlorinated biphenyl-containing concentration measuring method and the measuring method using the GC-MS method according to the embodiment is performed using a fluorescent X-ray analyzer. The chlorine concentration of the measurement sample was measured. Table 2 shows the results of comparing the PCB concentration derived from the chlorine concentration obtained by fluorescent X-rays for each lot of the measurement sample and the PCB concentration directly measured by the GC-MS method. FIG. 2 is a graph of the data in Table 2. The unit of the horizontal axis and the vertical axis is the concentration (mg / kg), respectively.

  From the data in Table 2 and from FIG. 2, in Example 1, the conversion coefficient between the PCB concentration value obtained from the fluorescent X-ray measurement and the PCB concentration obtained from the GC-MS measurement value has a good correlation. It is clear that it shows.

  Since the PCB concentration measurement method based on the GC-MS method is considered to obtain the closest data, the concentration measurement method based on the fluorescent X-ray measurement according to this embodiment of the present invention appropriately selects the conversion coefficient. It was confirmed that this would be used for accurate PCB concentration determination.

In the case of the ABS resin film of Example 1, the conversion coefficient A of Y = A · X in the formula (1) was 2.08. The coefficient of determination R ² of the correlation line of Figure 2 is 0.989, the correlation of the measured values was very high.

[Example 2]
[Measurement of polychlorinated biphenyl content in soil contaminated with PCB]
According to the flowchart shown in FIG. 1, as an example of a subject, a measurement sample sampled from soil containing PCB is measured by the polychlorinated biphenyl-containing concentration measurement method and the GC-MS method according to the above-described embodiment using a handheld fluorescent X-ray analyzer. Each measurement method was performed and the comparison was performed.

  The measurement results are shown in Table 3 and FIG.

In the case of the soil of Example 2, the conversion coefficient A was 2.70. The coefficient of determination R ² of the correlation line is 0.97, was very high correlation of the measured values. In the case of soil or sludge, the PCBs are relatively uniformly leveled and dispersed, so it is considered that the variation in measured values was small.

[Example 3]
[Measurement of polychlorinated biphenyl content in polyethylene film with PCB]
According to the flowchart shown in FIG. 1, as an example of the specimen, the chlorine concentration of each measurement sample was measured by a measurement method using a handheld X-ray fluorescence spectrometer and a GC-MS method for a measurement sample obtained by cutting and sampling a polyethylene film with PCB attached thereto. Were measured and compared.

  The measurement results are shown in Table 4 and FIG.

In the case of the polyethylene film of Example 3, the conversion coefficient A was 2.06. The coefficient of determination ^{R 2} of the correlation line was 0.72.

[Example 4]
[Measurement of polychlorinated biphenyl content in protective clothing with PCB attached]
According to the flowchart shown in FIG. 1, as an example of a subject, a method for measuring a polychlorinated biphenyl-containing concentration according to the above-described embodiment using a handheld X-ray fluorescence spectrometer for a measurement sample obtained by cutting and sampling a protective suit with PCB attached And the chlorine concentration of the measurement sample was measured by the measuring method by the GC-MS method, respectively, and the comparison was performed.

  The measurement results are shown in Table 5 and FIG.

In the case of the protective clothing of Example 3, the conversion coefficient A was 2.29. The coefficient of determination ^{R 2} of the correlation line was 0.47. For protective clothing, because the attachment site of the PCB can not be identified, given that PCB contamination level of the sampled measurement sample is different, the numerical value of 0.47 for the coefficient of determination R ² of the correlation line, the PCB concentration It is a level that can be used with sufficient confidence in the judgment.

[Example 5]
[Measurement of the concentration of polychlorinated biphenyls in insulator rubble with PCBs attached]
As an example of the subject, a measurement sample was prepared by pulverizing an insulator-type rubble (indefinite shape) with PCB attached thereto. At this time, the measured values by the analyzer were compared before and after grinding. For pulverization, a hammer was used and the particle size was reduced to 0.1 mm or less. An image imaging method using an optical microscope can be used for measuring the particle diameter. As a target test, the PCB concentration was measured by GC-MS measurement of the insulator rubble of the subject. In the GC-MS measurement, the specimen was ground and used as a measurement sample.

  The measured value of the insulator before pulverization (that is, the PCB concentration by the fluorescent X-ray measurement (insulator before pulverization)) <1> is higher than the actual PCB concentration (that is, the PCB concentration by the GC-MS measurement method) <3>. The reason for the significant increase is due to the detection of PCB attached to the insulator surface. Since the distribution of PCB is leveled as a whole measurement sample and within the measurement visual field by miniaturization, the measured value (ie, PCB concentration by fluorescent X-ray measurement (reel after grinding)) <2> actually Was able to be reflected.

[Example 6]
[Polyvinyl chloride determination]
As an example of the test object, the value of the chlorine concentration measured by fluorescent X-rays and the value of the PCB concentration measured by the GC-MS method were compared for polyvinyl chloride with PCB attached.

  The measured value <1> of the chlorine concentration by fluorescent X-ray is significantly higher than the PCB concentration <2> of the GC-MS method. In addition to chlorine in PCB, chlorine in polyvinyl chloride is detected. It is to do.

  As described above, when the chlorine concentration exceeds 200,000 mg / kg and it is determined in the chlorine-based resin determination step S15 that the subject is a resin by visual observation or infrared spectroscopy, the subject is a chlorine-based resin. It is determined that there is a possibility in the chlorine-based resin determination step S15, and as a result, the PCB concentration measurement by fluorescent X-rays is not performed. A PCB-containing concentration measurement step S07) is performed on the entire measurement sample.

[Use of protective film]
As another embodiment of the present invention, the use of the protective film 10 (see FIG. 1B) will be described.

  When measuring with a hand-held X-ray fluorescence analyzer as an example of the measuring instrument 2, the tip (for example, at least the end on the detection side) of the analyzer (for example, the measuring instrument 2) is brought into contact with the measurement sample 1. Yes. Therefore, a trace amount of PCB may adhere to the tip of the analyzer and affect the measurement data. As a countermeasure, a method using a protective film 10 that covers the tip of the analyzer (for example, at least the end on the detection side) can be employed. Most preferably, the protective film 10 is replaced every time the polychlorinated biphenyl-containing concentration measurement is performed. The material of the protective film 10 is not particularly limited as long as it does not contain a chlorine atom, but an olefin plastic film is preferable, and a polyethylene film is most preferable. Moreover, when using the film containing a chlorine atom as the protective film 10, the fluorescence X-ray intensity as the film 10 can be measured and correct | amended previously. The thickness of the polyethylene film as an example of the protective film 10 may be a thickness that does not affect the fluorescent X-ray measurement, more than 0 mm and 0.1 mm or less, and more preferably 0.05 mm or less. preferable.

  Even when a laminated polyethylene film in which a plurality of polyethylene films are laminated is used as the protective film 10, it is sufficient that the overall thickness exceeds 0 mm and is 0.1 mm or less. For example, when a laminated polyethylene film obtained by laminating five 0.01 mm films is used as the protective film 10, if the protective film 10 is first installed, the film is peeled off one by one for each measurement. The measurement sample can be measured under the same conditions. However, in this case, it is necessary to correct the conversion coefficient between one film of 0.01 mm and the laminated film.

  According to the above embodiment, the measurement target is not limited and the pretreatment process is not required, and the polychlorinated biphenyl waste contained in the polychlorinated biphenyl waste stored as the primary division in a simple manner at the storage location The concentration can be measured in a short time.

  Although it has been described that the polychlorinated biphenyl concentration in the measurement sample 1 is derived by multiplying the chlorine concentration data by the conversion coefficient A, the present invention is not limited to this. For example, a table or a graph is used. Thus, the polychlorinated biphenyl concentration may be derived from the chlorine concentration data.

  In addition, it can be made to show the effect which each has by combining arbitrary embodiment or modification of the said various embodiment or modification suitably. In addition, combinations of the embodiments, combinations of the examples, or combinations of the embodiments and examples are possible, and combinations of features in different embodiments or examples are also possible.

  In the method for measuring the concentration of polychlorinated biphenyls by fluorescent X-rays according to the above aspect of the present invention, the object to be measured is not limited and the pretreatment process is not required, and the polychlorinated biphenyl waste stored in the storage place The content concentration of the chlorinated biphenyl waste can be measured in a short time, and can be applied to the use as a primary classification by a simple method in classifying the low concentration polychlorinated biphenyl waste from the polychlorinated biphenyl waste.

DESCRIPTION OF SYMBOLS 1 Measurement sample 2 Measuring device 3 X-ray source 4 Semiconductor detector 5 GC-MS apparatus 6 Control part 7 Memory | storage part 8 Calculation part 10 Protective film

Claims (4)

Creating a measurement sample by leveling the polychlorinated biphenyl concentration in a specimen containing multiple types of polychlorinated biphenyl isomers;
Irradiating the measurement sample with X-rays from an X-ray source, measuring chlorine-specific fluorescent X-rays generated from the measurement sample with a semiconductor detector, and measuring the chlorine concentration;
Among the measurement samples, the chlorine concentration measured by the fluorescent X-ray measurement and the polychlorinated biphenyl concentration measured by the GC-MS method for the measurement samples having different chlorine concentrations prepared by the same type of analyte. And confirming the correlation between them, deriving the polychlorinated biphenyl concentration in the measurement sample based on the confirmed correlation data, and measuring the polychlorinated biphenyl-containing concentration,
Only including,
Creating the measurement sample by leveling the polychlorinated biphenyl concentration in the specimen,
Longest portion step a including dimensions to create the measurement sample to be miniaturized so that 0.5mm below, polychlorinated biphenyls-containing concentration measurement method by the fluorescent X-ray of the subject. Between the step of measuring the chlorine concentration by measuring the chlorine-specific fluorescent X-ray with the semiconductor detector and the step of deriving the polychlorinated biphenyl concentration and measuring the polychlorinated biphenyl-containing concentration,
Among the measurement samples, the chlorine concentration obtained by the fluorescent X-ray measurement takes a value equal to or higher than a resin determination threshold, and further includes a determination step of determining whether the measurement sample is a resin,
In the determination step, when the chlorine concentration obtained by the fluorescent X-ray measurement takes a value equal to or greater than the resin determination threshold, and when the measurement sample is determined to be resin, the polychlorinated biphenyl-containing concentration While performing the PCB content concentration measurement process in the entire measurement sample without performing the process of measuring
A step of measuring the polychlorinated biphenyl-containing concentration when the chlorine concentration obtained by the fluorescent X-ray measurement in the determination step is not a value equal to or higher than the resin determination threshold value or the measurement sample is not a resin. Carry out the
The method for measuring polychlorinated biphenyl-containing concentration by fluorescent X-rays according to claim 1. Deriving the polychlorinated biphenyl concentration and measuring the polychlorinated biphenyl-containing concentration,
Among the measurement samples, the chlorine concentration measured by the fluorescent X-ray measurement and the polychlorinated biphenyl concentration measured by the GC-MS method with respect to the measurement samples prepared by the same type of analyte and having different chlorine concentrations Deriving conversion coefficients by approximating the confirmed correlation with a straight line passing through the origin, and
A step of deriving a polychlorinated biphenyl concentration in the measurement sample by multiplying the chlorine concentration data obtained by the fluorescent X-ray measurement by the conversion coefficient, and measuring a polychlorinated biphenyl-containing concentration,
The step of deriving the polychlorinated biphenyl concentration comprises:
The chlorine concentration obtained by the fluorescent X-ray measurement is X (mg / kg), the polychlorinated biphenyl concentration is Y (mg / kg), and the conversion coefficient is a constant that varies depending on the type of the measurement sample. And when
Based on the following formula (1), the polychlorinated biphenyl concentration in the measurement sample is derived.
The polychlorinated biphenyl-containing concentration measuring method using fluorescent X-rays according to claim 1 or 2.
Y = A · X (1) A plastic film is provided as a protective film between the measurement sample and the semiconductor detector,
Replacing the plastic film for each measurement of the polychlorinated biphenyl concentration;
The polychlorinated biphenyl-containing concentration measuring method using fluorescent X-rays according to any one of claims 1 to 3 .

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