JP2007010371A - Harmful substance detecting system, detection method of harmful wood, and waste wood treatment system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a harmful substance detecting system, capable of simply and rapidly detecting the harmful substance, such as a preservative or the like, applied to the waste wood from a building or the like in real time, a detection method of harmful wood and a waste wood treatment system. <P>SOLUTION: The harmful substance detecting system for detecting the harmful substance 12 in waste wood 11 is constituted of a feed device 13 for feeding the waste wood 11, a laser-induced breakdown (LIBS) device 14 for detecting the harmful substance 12 in the waste wood 11, fed by the feed device 13 and a sorting device 17 for sorting only harmful wood 15 that contains the harmful substance 12 from harmless wood 16, on the basis of the signal from the laser-induced breakdown device 14. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a harmful substance detection system, a harmful wood detection method, and a waste wood treatment system that can easily and quickly detect harmful substances such as preservatives applied to waste wood from buildings and the like.

  In recent years, with the increasing awareness of resource recycling, the recycling of wood has been promoted, and in the recycling of waste wood, it is essential to ensure safety in recycling, but most of the wood has been subjected to antiseptic treatment. The antiseptic wood is required to be separately treated.

  Here, the preservative contains heavy metal substances such as chromium (Cr), copper (Cu), arsenic (As), and harmful wood containing such heavy metals (also referred to as CCA wood). When incinerated, heavy metals remain in the ash after incineration, and there is concern that it will have a negative impact on health and the environment. Therefore, conventionally, a sorting method using fluorescent X-rays has been proposed for sorting such harmful wood to which preservatives are attached (Patent Document 1).

JP 2003-270137 A

  However, in the fluorescent X-ray method according to Patent Document 1, light in the near-infrared wavelength band including at least a wavelength of 850 to 950 nm is irradiated, and based on the reflectance, at least the heavy metal contained in the preservative in the inspection object Although it is for determining the presence or absence of a substance, there is a problem that real-time measurement cannot be performed because a measurement time of about 2 minutes is required.

  Moreover, when measuring at the site | part of a waste wood processing, since the irradiation area of X-ray is about 5 mm in diameter, there exists a problem that the continuous selection during conveyance with a conveying apparatus is difficult.

  In view of the above problems, the present invention provides a harmful substance detection system and a harmful wood detection method that can easily and quickly detect harmful substances such as preservatives applied to waste wood from buildings and the like in real time. Another object of the present invention is to provide a waste wood treatment system that can effectively use harmless waste wood.

  A first invention of the present invention for solving the above-described problem is a harmful substance detection system for detecting a harmful substance in waste wood, the transport device transporting the waste wood, and the transport device transported to the transport device. A harmful substance detection comprising: a laser-induced breakdown device that detects harmful substances in waste wood, and a separation device that separates only harmful wood containing harmful substances based on a signal from the laser-induced breakdown device In the system.

  2nd invention has a crusher which crushes the said waste wood in 1st invention, and conveys the wood crushed by the said crusher with the said conveyance apparatus, The hazardous | toxic substance detection system characterized by the above-mentioned. It is in.

  A third invention is the harmful substance detection system according to the first or second invention, wherein the measuring section of the laser-induced breakdown device is capable of reciprocating in a direction orthogonal to the wood conveying direction.

  A fourth invention is the harmful substance detection system according to any one of the first to third inventions, wherein the wavelength of the detection unit of the laser-induced breakdown device is 265 to 365 nm.

  A fifth invention is the harmful substance detection system according to any one of the first to fourth inventions, wherein the harmful substance is at least one of chromium, copper, and arsenic.

  A sixth aspect of the invention is a method for detecting harmful wood, characterized by using the harmful substance detection system according to any one of the first to fourth aspects to detect chromium by detecting chromium.

  The seventh invention includes a harmful substance detection system according to any one of the first to fifth aspects, a harmless wood recovery processing device for recovering and processing harmless wood excluding wood containing harmful substances, and recycling for recycling the recovered harmless wood A waste wood treatment system comprising a treatment device.

  An eighth invention is the waste wood treatment system according to the seventh invention, wherein the recycling treatment apparatus is a biomass gasification furnace or a carbonization furnace.

  According to the harmful substance detection system of the present invention, it is possible to easily and quickly detect harmful substances such as preservatives applied to waste wood from buildings and the like in real time. Moreover, according to the waste wood processing system of the present invention, harmless waste wood can be effectively used.

  Hereinafter, the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments. In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art or those that are substantially the same.

A harmful substance detection system according to a first embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic diagram illustrating a hazardous substance detection system according to the first embodiment.
As shown in FIG. 1, a harmful substance detection system 10-1 according to the present embodiment is a harmful substance detection system that detects a harmful substance 12 in waste wood 11, and includes a transport device 13 that transports the waste wood 11. A laser induced breakdown (LIBS) device (hereinafter referred to as a “LIBS device”) 14 for detecting harmful substances 12 in the waste wood 11 transported to the transport device 13, and the laser induced break It comprises a sorting device 17 for sorting only harmful wood 15 containing harmful substances from harmless wood 16 by a signal S from the down device 14.
The harmful wood 15 sorted by the sorting device 17 is removed to the outside by the transport device 13a. Further, the harmless wood 16 is sent to the recycling process by the transport device 13b.

  The LIBS device measures the amount of harmful substances on-line by irradiating the waste wood 11 with laser light by using a laser-induced breakdown spectroscopy method to turn harmful wood into plasma, and by analyzing the generated plasma light. To do.

  As shown in FIG. 2, the LIBS device 14 includes a laser device 21, a converging lens 22, a condensing lens 23 for plasma emission light P, a spectroscope 24, and a calculator (CPU) 25.

  As shown in FIG. 1, laser light L is irradiated from the laser device 21 to the surface of the waste wood 11 conveyed by the conveying device 13, and when there is a harmful substance 12, plasma is emitted. The light is analyzed by the spectroscope 24 to obtain an emission spectrum.

  FIG. 3 shows the principle of the LIBS method. When a harmful substance (CCA agent) 12 is irradiated with laser light L, it is converted from plasma atoms such as chromium (Cr), copper (Cu), and arsenic (As). You can see how the luminescence phenomenon appears.

FIGS. 4-1 to 6-2 show examples of emission spectra.
Fig. 4-1, Fig. 5-1, and Fig. 6-1 are emission spectra of normal harmless wood. Fig. 4-1 shows the emission state measured at wavelengths of 352 to 365 nm. The light emission state at 265 to 280 nm is measured, and FIG. 6A is the light emission state at a wavelength of 320 to 335 nm.
4-2, 5-2, and 6-2 are emission spectra of harmful wood containing harmful substances, and FIG. 4-2 is a measurement of the emission state of Cr at wavelengths of 352 to 365 nm. -2 is a measurement of the emission state of As at a wavelength of 265 to 280 nm, and FIG. 6-2 is a measurement of the emission state of Cu at a wavelength of 320 to 335 nm.
The vertical axis indicates the intensity.
As shown in the figure, among Cr, As and Cu, regarding Cr, harmless wood and harmful wood can be clearly distinguished, and detection of Cr can greatly improve the detection accuracy of harmful wood as well. It becomes.

Here, the conditions of the LIBS apparatus 14 in FIGS. 4-1 to 6-25 are as follows: the laser energy is 20 mJ / p, the laser wavelength is 1064 nm, the delay time (timing for measurement after laser irradiation) is 2 μs, and the gate. The time (measurement time) is 1 μs.
Here, the laser energy is 20 mJ / p, but is preferably 1 to 100 mJ / p. The laser wavelength is 1064 nm, but is preferably 500 to 1100 nm. The delay time is 2 μs, but it is preferably 1 to 5 μs. Furthermore, although the gate time is 1 μs, it is preferably 500 ns to 2 μs.

  FIG. 7 is a graph showing the relationship between the Cr signal intensity and the Cr concentration (ppm). Thereby, harmful wood with a Cr content of about several ppm can be separated and removed.

  As described above, according to the harmful substance detection system 10-1 of the present embodiment, it is possible to detect, for example, harmful wood treated with a CCA agent in real time, and by separating and removing only the harmful wood 15. Only the harmless wood 16 can be used for recycling.

A harmful substance detection system according to a second embodiment of the present invention will be described with reference to the drawings.
FIG. 8 is a schematic diagram illustrating a hazardous substance detection system according to the second embodiment. In addition, about the same structure as the harmful | toxic substance detection system 10-1 of Example 1, the same code | symbol is attached | subjected and the description is abbreviate | omitted.
As shown in FIG. 8, the harmful substance detection system 10-2 according to the present embodiment is a harmful substance detection system that detects a harmful substance 12 in the waste wood 11, and is a wood crusher that crushes the waste wood 11. 31, a transport device 13 that transports the crushed wood 32 crushed by the wood crusher 31, a LIBS device 14 that detects harmful substances 12 in the waste wood 11 transported to the transport device 13, and the LIBS device The separation device 17 separates only the harmful wood 15 containing harmful substances from the harmless wood 16 by the signal from 14.

In this embodiment, the harmful wood 15 sorted by the sorting device 17 is sent to the harmful wood treatment process by the transport device 13a. Further, the harmless wood 16 is sent to the recycling process.
Thereby, the harmful wood 15 and the harmless wood 16 are separated.

In this embodiment, since the wood crusher 31 that crushes the waste wood 11 into a predetermined size is used, the detection sensitivity of harmful substances in the LIBS apparatus is improved.
The wood crusher 31 can change the size of the crushed wood 32 to be crushed by changing the blade for crushing. As a magnitude | size which the detection sensitivity in the LIBS apparatus 14 becomes high, what is necessary is just to be about 20 cm long x 5 cm wide x 3 cm thick, for example.
Thereby, the crushed crushed wood is not diluted and can be carried by the transport device 13 as a certain amount of lump. Here, the preferable range of the wood to be crushed is preferably 20 cm ± 5 cm in length, 5 cm ± 3 cm in width, and 3 cm ± 2 cm in thickness.

  FIG. 9 is a diagram showing the relationship between the LIBS device 14 and the transport device 13. As shown in FIG. 9, the measuring unit 14a of the LIBS device 14 is provided in a moving jig 42 having a distance meter 41 that is movable in a direction orthogonal to the conveying direction of the conveyor 13a of the conveying device 13, and the conveyor 13a The upper crushed wood 32 is irradiated with laser light L. At this time, a distance meter 41 is provided so as to maintain a constant distance between the crushed wood 32 of the conveyor 13a and the measuring unit 14a.

  Here, the speed of the conveyor 13a of the conveying device 13 that is normally used is about 1 m per second, but the detection by the LIBS device 14 is performed by adjusting the speed to around 50 cm per second. Further, when the width of the conveyor is about 60 cm, the moving speed of the measuring unit 14a is set to be one reciprocation per second in order to increase the detection sensitivity.

  Further, as shown in FIG. 10, the processing speed 25 of the conveyor 13a, the measurement position X by the measurement unit 14a of the LIBS device 14 and the information of the measurement time T are processed by the calculator 25, so that the classification is an example of a sorting device. Each opening of the shooter (A, B, C) 17a may be opened so that only harmful wood can be separated.

A waste wood treatment system according to Embodiment 3 of the present invention will be described with reference to the drawings.
FIG. 11 is a schematic diagram illustrating a waste wood processing system according to the third embodiment. As shown in FIG. 11, the waste wood processing system 50 according to the present embodiment collects the harmful substance detection system 51 according to the first or second embodiment and the harmless wood 16 excluding the harmful wood 15 containing harmful substances. A harmless wood recovery processing device 52 for processing and a recycling processing device 53 for recycling the recovered harmless wood 16 are provided.

Here, in this embodiment, examples of the recycle processing apparatus 53 that recycles the recovered harmless wood 16 include a biomass gasification furnace or a carbonization furnace.
As a result, the obtained product (methane gas, carbide, etc.) 54 has no harmful substances.
The separated hazardous wood 15 is separately processed by the hazardous waste processing apparatus 55.

In addition to recycling with a biomass gasification furnace or carbonization furnace, harmless wood can be used as an alternative to, for example, pulp raw materials, particle board raw materials, and litter.
In this way, in the recycling of waste wood, for example, waste materials that have been preserved with harmful substances such as CCA agents can be efficiently separated, so that the safety of recycling of the waste materials can be ensured while improving the recycling efficiency and recycling. Cost can be reduced.

  As described above, the hazardous substance detection system according to the present invention can easily and quickly detect harmful substances such as preservatives applied to waste wood from buildings and the like in real time, Suitable for effective use.

1 is a schematic diagram illustrating a harmful substance detection system according to a first embodiment. It is explanatory drawing which shows the principle of a LIBS method. It is explanatory drawing which shows the structure of the LIBS apparatus which is one structure of the system of FIG. It is a figure which shows an example of the emission spectrum of harmless wood. It is a figure which shows an example of the emission spectrum (Cr) of harmful wood. It is a figure which shows an example of the emission spectrum of harmless wood. It is a figure which shows an example of the emission spectrum (As) of harmful wood. It is a figure which shows an example of the emission spectrum of harmless wood. It is a figure which shows an example of the emission spectrum (Cu) of harmful wood. It is a relationship diagram between Cr concentration and Cr signal intensity. It is the schematic which shows the hazardous | toxic substance detection system which concerns on Example 2. FIG. It is the schematic which shows the conveying apparatus and LIBS apparatus which concern on Example 2. FIG. FIG. 6 is a schematic plan view of a transport device according to a second embodiment. It is the schematic which shows the waste wood processing system which concerns on Example 3. FIG.

Explanation of symbols

10-1, 10-2 Harmful material detection system 11 Waste wood 12 Harmful material 13 Transport device 14 LIBS device 15 Harmful wood 16 Harmless wood 17 Sorting device 32 Crushed wood

Claims (8)

A hazardous substance detection system for detecting harmful substances in waste wood,
A transport device for transporting the waste wood;
A laser-induced breakdown device for detecting harmful substances in waste wood conveyed to the conveying device;
A harmful substance detection system comprising: a sorting device for sorting only harmful wood containing harmful substances based on a signal from the laser-induced breakdown device. In claim 1,
A hazardous substance detection system comprising a crusher for crushing the waste wood, and conveying the wood crushed by the crusher with the transport device. In claim 1 or 2,
The hazardous substance detection system, wherein the measurement unit of the laser-induced breakdown device is capable of reciprocating in a direction perpendicular to the wood conveying direction. In any one of Claims 1 thru | or 3,
The harmful substance detection system according to claim 1, wherein the wavelength of the detection unit of the laser induced breakdown device is 265 to 365 nm. In any one of Claims 1 thru | or 4,
The harmful substance detection system, wherein the harmful substance is at least one of chromium, copper, and arsenic.   A method for detecting harmful wood, wherein the harmful wood is detected by detecting chromium using the harmful substance detection system according to any one of claims 1 to 4. A harmful substance detection system according to any one of claims 1 to 5,
Harmless wood recovery processing equipment that recovers and processes harmless wood excluding wood containing harmful substances,
A waste wood treatment system comprising a recycling device for recycling the collected harmless wood. In claim 7,
The waste wood treatment system, wherein the recycling treatment apparatus is a biomass gasification furnace or a carbonization furnace.

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