JP4517877B2 - VOC collector - Google Patents

Description

  The present invention relates to a VOC collection device for collecting VOCs emitted from building materials, vehicle seats, and the like.

There is concern about the health effects of volatile compounds (hereinafter abbreviated as VOC) emitted from interior materials such as seats in automobile interiors. In order to improve indoor air quality, it is necessary to grasp what components are generated from the current interior parts.
Conventionally, in order to collect VOCs emitted from building materials, car seats, etc., JIS A1901 has standardized a method in which the entire sample is placed in a huge sealed container or room and diffused over a long period of time. (Internal volume of 20 liters or more, time of 24 hours or more).
However, in such a method, (1) the apparatus is huge, (2) it is necessary to put the measurement object in the huge apparatus as it is, and (3) the internal volume is large, so the time for stabilizing the state is long. In recent years, a simple VOC collection method has been studied.
For example, in Patent Documents 1 and 2, a sample surface of a predetermined area is covered with a casing having a predetermined internal volume, and a VOC diffused in the casing is collected by connecting a collection pipe to the casing and collecting the VOC through the collection pipe. A collection device has been proposed. According to these prior art documents, it becomes possible to collect VOCs dissipated from a sample with a small device. FIG. 9 shows an outline of an example of a conventional small VOC collection device. An outer cylinder 52 is further arranged on the outer peripheral side of the casing 50 to which the collection pipe 51 is connected, and the casing 50, the outer cylinder 52, Air or the like is supplied between them to ensure isolation between the inside of the casing and the outside. VOCs diffused from the surface of the sample 10 covered with the casing 50 are secured by the casing 50 and collected by the collecting tube 51.
JP 2002-122521 A JP 2004-163208 A

By the way, it is known that the VOC emission rate largely depends on the surface area of the sample and the volume to be emitted. That is, when the space volume ratio (material load factor) differs from that of the sample, the dissipative concentration also varies greatly. Therefore, when evaluating the spatial concentration, how to set the material load factor is the key to the evaluation. Therefore, in order to collect VOCs according to the usage mode of samples such as building materials and car seats, the surface area or the internal volume of the collector is determined based on the surface area of the samples and the volume of the place where the samples are used. It is necessary to adjust to collect VOCs at an appropriate material loading factor (member surface area / chamber volume).
However, since the conventional simple VOC collection device has only a fixed internal volume, it is not possible to collect VOC by reproducing the VOC emission rate in a state close to that of the usage mode. Therefore, there is a problem that it is impossible to measure the sample as it is without processing the sample.

  The present invention has been made against the background of the above circumstances, and by setting an appropriate material load factor (member surface area / chamber volume) without processing the sample, the VOC emission rate is close to the usage mode. An object of the present invention is to provide a VOC collecting device that can reproduce and collect VOCs.

That is, among the VOC collection devices of the present invention, the invention according to claim 1 is characterized in that a part or all of a sample is placed inside to enclose a volatile compound to be emitted from the sample, and the volatile compound is captured. A collecting section, and a chamber that is interposed between the casing and the collecting section so as to be ventilated and variable in internal volume, and the chamber includes a plurality of predetermined chambers. It is characterized by having at least one partition wall that partitions the interior based on the installation position and can change the internal volume of the chamber in stages .

According to a second aspect of the present invention, there is provided the VOC collecting device according to the first aspect, wherein the chamber is provided with fixed walls at a plurality of positions where the internal volume of the chamber can be changed. And a sealing member that has a communication portion that communicates with both sides of the first and second walls, seals any one of the communication portions, and uses the fixed wall as the partition wall.

According to a third aspect of the present invention, there is provided the VOC collecting device according to the second aspect , wherein the plurality of fixed walls are provided with communicating portions at alternate positions along the ventilation direction of the volatile compound. Features.

According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the position of the communicating portion with respect to the casing can be changed according to the position of the partition wall. .

The VOC collection device according to claim 5 is characterized in that, in the invention according to any one of claims 1 to 4 , the position of the communication portion with respect to the collection portion can be changed according to the position of the partition wall. And

  That is, according to the present invention, since the chamber is connected to the casing so as to communicate with the casing, the dissipating internal volume when the VOC is dissipated from the sample placed in the casing is determined by the internal volume of the casing and the chamber. The internal volume is added and VOC is collected in a short time. Although the inner volume of the casing is fixed, the inner volume of the chamber is variable, and the dissipating inner volume is changed by changing the inner volume of the chamber. Therefore, it is possible to set a desired dissipating internal volume by changing the internal volume of the chamber without adjusting the surface area of the sample, and to collect VOCs with an appropriate material load factor (member surface area / chamber volume) according to the usage form of the sample can do. The collected VOC is collected by an adsorbent or the like through a collection unit such as a collection tube, and can be used for analysis or the like.

In addition, the configuration for making the chamber variable is not particularly limited as the present invention, and it is continuously changed, changed stepwise, changeable to an arbitrary value, set to a preset value. Any of those that can be changed may be used.
The internal volume of the chamber can be changed stepwise by installing partition walls that partition the interior at a plurality of predetermined installation positions.

  Note that the partition wall is not limited to a specific structure as long as it can be installed at a predetermined position manually or using an appropriate actuator or the like. For example, a locking portion such as a concavo-convex shape for locking the partition wall in the chamber is provided in accordance with the predetermined installation position, and a locking portion such as a concavo-convex shape locking to the locking portion is provided on the partition wall side. The partition can be installed by providing and locking these locking portions to each other. It is also possible to change the installation position of the partition wall by providing a fixed wall (plate material, diaphragm, etc.) having a communication part in the chamber and opening and closing the communication part.

  In addition, when changing the installation position of a partition, the flow path of VOC can be adjusted by enabling the position of the communicating part with respect to the casing or the communicating part with respect to the collecting part to be changed. The maximum length or a distance close to this is obtained from the communication part to the communication part of the collection part. Therefore, it is desirable to provide a communication part for the casing or the collecting part in the vicinity of the partition wall that partitions the internal space of the chamber. By ensuring a sufficiently long flow path for the VOC to move in the chamber, uniform diffusion of the VOC is promoted.

Furthermore, as shown in claim 3 , a plurality of the fixed walls are provided in the chamber, and the communication portions provided in the fixed walls are provided at alternate positions between the fixed walls along the ventilation direction of the VOC. As a result, convection and stirring of the VOC become active, and the VOC becomes more uniform.

As described above, according to the VOC collection device of the present invention, a casing that encloses a volatile compound that dissipates from a sample by placing a part or all of the sample inside, and a collection that collects the volatile compound. A collecting portion, and a chamber interposed between the casing and the collecting portion so as to be able to vent each other and having a variable internal volume, the chamber at a plurality of predetermined installation positions. It is possible to collect and evaluate VOCs easily and in a short time without using a huge device because it has at least one partition wall that can partition the interior and change the internal volume of the chamber in stages. Furthermore, the VOC emission rate can be adjusted by adjusting the internal volume of the VOC collector without adjusting the surface area of the sample. As a result, there is no need to process the target sample, and it is possible to ensure the VOC emission rate according to the actual usage of the sample. And according to this invention, it can be set as the small type which can be carried on the sample surface, and it becomes possible to perform on-site evaluation of a big member, an actual member, etc. efficiently. For example, all evaluations can be completed in about half a day.

Below, one Embodiment of this invention is described based on FIG.
FIG. 1 is a front sectional view showing an outline of the VOC collection device 1 of the present invention, and FIG. 2 is a plan sectional view taken along line II-II in FIG.
A VOC collection device 1 includes a casing 2 having a double outer wall and a funnel shape with an opening facing downward, and a box located above the casing 2 and connected to the casing 2 so as to allow ventilation. And a collecting part (only the collecting tube 4 is shown in the figure) connected to the chamber 3 so as to allow ventilation.

The casing 2 has a communication pipe 21 that communicates with the internal space 20 surrounded by the double outer wall 22 and that opens to the top. The casing communication section provided in the lower central part of the chamber 3 is connected to the communication pipe 21. 31 is connected so that ventilation | gas_flowing is possible. The double outer wall 22 of the casing 2 has a double structure as described above, and the double wall inner space 23 is formed in a cylindrical shape and opens downward. Further, on the upper side of the casing 2, there is a cylindrical portion 24 which surrounds the communication pipe 21 and whose upper end is closed. An external gas supply pipe 5 is connected to the side of the cylindrical portion 24.
In this embodiment, the case of the double outer wall structure has been described as the structure of the casing. However, the structure of the casing is not limited to a specific structure in the present invention, and a VOC diffused from the sample is secured. Any structure can be used.

Next, the internal space 30 in the chamber 3 communicates with the casing communication part 31 in the lower part and communicates with the collection pipe communication part 32 in the upper part. The collection pipe communication part 32 is further connected to the collection pipe 4 constituting a part of the collection part. The chamber 3 includes a plurality of partition walls 33a to 33d that partition the internal space 30, and each partition wall can be detached and installed independently. Therefore, the internal volume of the internal space 30 can be changed by attaching and detaching each partition wall. It should be noted that the installation positions of the partition walls 33a... 33d are preferably set in advance, so that the operator can easily and gradually change the internal volume of the internal space 30. The upper wall portion 34 of the chamber 3 can be removed. When changing the installation state of the partition walls 33a... 33d, after removing the upper wall portion 34, the desired partition wall is detached and then removed. By attaching the upper wall portion 34, it can be used as the chamber 3 in which the internal volume of the internal space 30 is set. For example, the internal space surrounded by the partition walls 33b and 33c can be approximately doubled by removing the partition wall 33b, and can be tripled by removing the partition wall 33c.
When the installation position of each partition wall is predetermined, it is desirable that a fitting portion is formed between the partition wall and the chamber inner wall so that the partition wall can be easily attached and detached at a predetermined position.
Moreover, the above-described collection tube 4 constitutes a part of the collection unit, contains an adsorbent, and is connected to an analysis device (not shown). However, the configuration of the collection unit is not limited to a specific one as long as the present invention has a function capable of collecting the captured VOC.

Next, the VOC collection operation using the VOC collection device 1 will be described.
First, a necessary material load factor is determined in consideration of the usage pattern of the sample. This material load factor a is defined as the surface area S of the sample, the internal volume Vc of the casing 2, and the internal volume Vx of the chamber 3.
a = S / (Vc + Vx).
Here, since S and Vc are fixed, a desired material load factor can be obtained by changing the internal volume Vx of the chamber 3. Therefore, the inner volume in the chamber 3 is determined by detaching each partition wall in accordance with a desired material load factor. As described above, the separation of the partition walls can be easily performed by removing the upper wall portions 34 and detaching the partition walls, and then attaching the upper wall portions 34.

Next, the opening of the casing 2 of the VOC collection device 1 is installed on the surface of the sample 10. At this time, the tip of the double outer wall 22 is in close contact with the sample 10, whereby a predetermined surface area of the sample 10 is surrounded by the casing 2.
Next, a shield / carrier gas such as pure air or inert gas is introduced from the gas supply pipe 5 at an appropriate number of times and intervals. The gas descends in the double-wall inner space 23 and is discharged outward and inward from its tip. This gas flow ventilates the internal spaces 20 and 30 and prevents contamination from the external space.
From the surface of the sample 10, VOC is diffused into the internal space having the internal volume of (Vc + Vx). After the VOC emission for a predetermined time, the VOC in the internal spaces 20 and 30 is collected by the collection tube 4 by transferring the VOC by introducing the gas through the gas supply tube 5 or by suction in the collection unit. Then, a desired detection operation or the like is performed.
Further, when collecting VOCs from other types of samples, an internal volume required for VOC emission is set, and the partition walls 33a to 33d of the chamber 3 are desorbed based on the set internal volume. Change the internal volume. Thereafter, VOC recovery from the sample can be performed with an appropriate material loading rate in the same manner as described above.

Below, other embodiment is described based on FIG. In addition, about the structure similar to the said embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted or simplified.
In the above embodiment, the inner volume of the chamber can be changed by detaching the partition wall. However, in the embodiment described below, one partition wall 33 is disposed in the chamber 3 so as to be slidable. The internal volume of the internal space 30 can be changed. The sliding position of the partition wall 33 is determined at three locations a, b, and c. Therefore, the internal volume of the chamber 3 can be changed in stages. In accordance with the movement of the partition wall 33, collection pipe communication portions 32a to 32d communicating with the collection pipe 4 are provided in the vicinity of the movement position of the partition wall 33 (near the left side in the drawing). The collecting pipe communicating portions 32a... 32d communicate with the interior of the chamber 3, and open / close valves 35a. On the other hand, the casing communication part 31 is provided below the end part (the left end in the figure) of the chamber 3. The upper wall portion 34 of the chamber 3 is removable, and when the installation position of the partition wall 33 is changed by sliding, the partition wall is moved to a desired position after the upper wall portion 34 is removed, and thereafter By attaching the upper wall portion 34 and fixing with the clamp 36, the chamber 3 can be used. The partition wall 33 can be slid mechanically using an actuator or the like in addition to being slid manually.
For example, when the partition wall 33 is moved to the position a, the internal space 30 has the smallest internal volume, and the internal volume increases as the partition wall 33 is moved to the positions b and c. At that time, the opening / closing of the opening / closing valves 35a ... 35d is adjusted according to the movement position of the partition wall 33, the opening / closing valve closest to the partition wall 33 is opened, and the opening / closing valve on the left side of the opening / closing valve is closed.

  In the above embodiment, the inner volume of the chamber 3 is changed with the movement of the partition wall 33, the position of the collection pipe communication part is changed, and the distance from the casing communication part 31 to the collection pipe communication part is the longest. The position of the collecting pipe communicating portion is determined so as to be a large distance. This ensures a long flow path in the chamber 3, so that when the VOC moves in the chamber 3, the VOC can diffuse evenly, reducing the variation in the analysis of the VOC after collection. Analysis accuracy.

Next, another embodiment will be described with reference to FIG.
In each of the above embodiments, the apparatus for changing the internal volume of the chamber in stages has been described. However, in the following embodiments, the internal volume of the chamber can be changed continuously. In addition, about the structure similar to the said embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted or simplified.
The casing 200 has a dome shape that is hollow inside and opened at the bottom, and a communication pipe 202 that communicates with the internal space 201 of the casing 200 is provided at an upper portion thereof. A casing communication pipe 302 (corresponding to a casing communication part) of the chamber 300 is connected to the communication pipe 202 via an on-off valve 203. The casing communication pipe 302 is connected to a common pipe 303 that reaches the chamber 300, and the common pipe 303 communicates with the internal space 301 of the cylinder-type chamber 300. The internal space 301 is configured to be surrounded by a main body inner wall of the chamber 300 and a piston 305 that can slide on the main body inner wall, and the internal volume can be continuously changed by sliding the piston 305. it can. The piston 305 can be slid through the rod 306 manually or by an actuator operation.
The common pipe 303 is connected to a collection part communication pipe 304, and the collection pipe 400 is connected to the collection part communication pipe 304.

In the VOC collection device, the VOC diffusion space is configured by the internal space 201 and the internal space 301, and the internal volume of the internal space 301 is adjusted by sliding the piston 305 to match the internal volume of the internal space 201. Thus, a desired internal volume is obtained. The VOC diffused from the sample 10 is captured in the internal space 201 and the internal space 301 and collected through the collection tube 400.
In the above embodiment, the internal volume of the chamber can be arbitrarily changed continuously, so that various internal volumes can be obtained. However, the one that can be set in multiple stages with a predetermined value as in the above-described embodiment has an advantage that the operator can easily and quickly set the internal volume. Moreover, in the said embodiment, it can also be set as the structure which changes a chamber internal volume in steps so that a piston can be moved only to a predetermined position.

Next, another embodiment will be described with reference to FIGS.
In the chamber 310 shown in FIG. 5, plate-like fixed walls 331 to 337 are arranged at predetermined intervals in the left-right direction shown in FIG. 5, and each fixed wall communicates by separating one end side from the inner wall of the chamber 310. Portions 321 to 327 are provided. The fixed walls 331, 333, 335, and 337 have communication portions 321, 323, 325, and 327 on the lower end side in the figure, and the fixed walls 332, 334, and 336 have communication portions 322 and 324 on the upper end side in the figure. 326. As described above, the communication portions are provided at alternate positions in the vertical direction along the illustrated left-right direction (air flow direction). Among the communication portions, the communication portions 322, 324, and 326 can be sealed by disposing and engaging a sealing plate 330 as a sealing member. The fixed wall that seals the communication portion functions as a partition that partitions the interior of the chamber.

  A method for engaging the fixed walls 332 and 334 or the fixed wall 336 with the sealing plate 330 is shown in FIG. 6 taking the fixed wall 332 as an example. That is, the concave portion 332 a is formed on the upper end surface of the fixed wall 332, and the convex portion 330 a that can be engaged with the concave portion 332 a is formed on the lower end surface of the sealing plate 330. On the other hand, the concave portion 34 b is formed on the lower surface of the upper wall portion 34, and the convex portion 330 b is formed on the upper end surface of the sealing plate 330. When the communication portion 322 is sealed by the sealing plate 330, the clamp 36 is removed and the upper wall portion 34 is opened, the concave portion 332a and the convex portion 330a are engaged, and the upper wall portion 34 is covered. Meanwhile, the convex portion 330b and the concave portion 34b are fitted. Thereafter, the clamp 36 is attached to obtain the chamber 3 having a predetermined internal volume. The fixed walls 334 and 336 have the same configuration, and a concave portion is formed on the lower surface of the upper wall portion 34 corresponding to the positions of the fixed walls. By selecting the fixed wall to which the sealing plate 330 is attached, the internal volume of the internal space 320 in the chamber 3 can be changed stepwise.

Further, in the chamber 310 of this embodiment, the casing communication portion 311 is provided on the lower left side of the chamber 310 in the figure, and the collecting tube communication portions 312, 314, 316, and 318 are respectively fixed walls 332, 334, 336, Near the left side of the right inner wall 310 a of the chamber, it is provided on the upper wall portion 34, and each collection tube communication portion communicates with the inside of the chamber 310. The collection pipe communication portions 312, 314, 316, and 318 are provided with on-off valves 313, 315, 317, and 319, respectively, and the collection pipe communication portion in the vicinity of the partition wall is communicated with the collection pipe. It is possible to close the collecting pipe communicating portion on the left side.
With the above configuration, the VOC introduced from the casing communication part 311 passes through a communication part located on the lower side of the internal space 310 and then moves upward, and then is regulated by the partition wall to the left of the partition wall. The VOC is uniformly diffused while being agitated by combining the movement to the right in the figure and the vertical movement through the collection pipe communicating portion located on the upper side. Further, since the collecting pipe communicating portion is located at a position close to the partition wall, the flow path length in the internal space is sufficiently secured, and the uniform diffusion becomes better.

Next, still another embodiment will be described with reference to FIGS.
In the chamber 350 shown in FIG. 7, film-like fixed walls 371 to 377 are arranged at predetermined intervals in the left-right direction shown in FIG. 7. In each fixed wall, a through hole is formed close to the end side. The communication portions 361 to 367 are provided. The fixed walls 371, 373, 375, and 377 have communication portions 361, 363, 365, and 367 located on the lower end side in the figure, and the fixed walls 372, 374, and 376 have communication portions 362, 364, and 366 on the upper end side in the figure. Is located. As described above, the communication portions are alternately positioned up and down along the horizontal direction (air flow direction) in the figure. Among the communication portions, the communication portions 362, 364, and 366 are provided with a sealing film 370 as a sealing member, and the communication portions can be sealed by engagement. The fixed wall that seals the communication portion functions as a partition that partitions the internal space of the chamber 350.

FIG. 8 shows a method for engaging the fixed walls 372 and 374 or the fixed wall 376 with the sealing film 370 by taking the fixed wall 372 as an example. That is, on the right side surface of the fixed wall 372, a slide frame 372a that is detachable by opening the one direction and sliding the sealing film 370 is installed. When the communication part 362 is sealed by the sealing film 370, the clamp 36 is removed and the upper wall part 34 is opened, and then the sealing film 370 is slid into the slide frame 372a, and the communication part 362 is inserted. Seal. Thereby, the fixed wall 372 functions as a partition wall. After that, the chamber 350 having a predetermined internal volume is obtained by attaching the clamp 36. The fixed walls 374 and 376 have the same configuration. By selecting a fixed wall to which the sealing film 370 is attached, the internal volume of the internal space 360 in the chamber 350 can be changed stepwise. Also in the chamber 350 of this embodiment, the casing communication portion 351 is provided on the lower left side of the chamber 350 in the figure, and the collecting tube communication portions 352, 354, 356, 358 are respectively fixed walls 372, 374, 376, The upper wall 34 is provided in the vicinity of the left side of the right inner wall 350 a of the chamber 350. Each collection tube communication portion communicates with the inside of the chamber 350. The collecting pipe communicating portions 352, 354, 356, and 358 are provided with on-off valves 353, 355, 357, and 359, respectively, and the collecting pipe communicating portions in the vicinity of the partition walls communicate with the collecting pipe. It is possible to close the collection-related passage on the left side.
With the above configuration, the VOC introduced from the casing communication portion 351 combines the rightward movement and the vertical movement in the figure, and the VOC is uniformly diffused through a sufficiently long flow path.
As mentioned above, although this invention was demonstrated based on the said embodiment, this invention is not limited to the content of the said embodiment, A change is possible in the range which does not deviate from the scope of the present invention.

It is the front view which carried out the section which shows the VOC collection device of one embodiment of the present invention partially. Similarly, it is the II-II sectional view taken on the line of FIG. It is a cross-sectional front view which shows the chamber in other embodiment of this invention. It is the front view which carried out the cross section of a part which shows the VOC collection device in other embodiments of the present invention. It is a cross-sectional front view which shows the chamber in other embodiment of this invention. Similarly, it is a partially expanded perspective view showing a fixed wall engaged with a sealing member. It is a cross-sectional front view which shows the chamber in other embodiment of this invention. Similarly, it is a partially expanded perspective view which shows the fixed wall which has arrange | positioned the sealing member. It is a figure which shows the outline of the conventional VOC collection apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 VOC collection apparatus 2 Casing 3 Chamber 4 Collection pipe 20 Internal space 21 Communication pipe 30 Internal space 31 Casing communication part 32 Collection pipe communication part 32a, 32b, 32c, 32d Collection pipe communication part 33 Moving partition 33a, 33b 33c, 33d Bulkhead 200 Casing 201 Internal space 300 Chamber 301 Internal space 302 Casing communication pipe 304 Collection part communication pipe 305 Piston 310 Chamber 311 Casing communication part 312, 314, 316, 318 Collection pipe communication part 320 Internal space 321, 322, 323, 324, 325, 326, 327 Communication portion 330 Sealing plate 331, 332, 333, 334, 335, 336, 337 Fixed wall 350 Chamber 361, 362, 363, 364, 365, 366, 367 Communication portion 370 Sealing film 3 71, 372, 373, 374, 375, 376, 377 Fixed wall

Claims (5)

A casing that encloses a volatile compound that dissipates from the sample with a part or all of the sample placed inside, a collection part that collects the volatile compound, and is interposed between the casing and the collection part. Chambers that are connected to each other so as to be able to ventilate and whose inner volume is variable, and the chamber can partition the interior based on a plurality of predetermined installation positions and change the inner volume of the chamber in stages. A VOC collection device comprising at least one partition wall . Each of the chambers has a fixed wall at a plurality of positions where the internal volume of the chamber can be changed. The fixed wall has a communication portion communicating with both sides of the fixed wall, and any one of the communication portions. The VOC collection device according to claim 1, further comprising: a sealing member that seals the wall and uses the fixed wall as the partition wall . The VOC collection device according to claim 2, wherein each of the plurality of fixed walls is provided with a communication portion at an alternate position along the ventilation direction of the volatile compound . The VOC collection device according to any one of claims 1 to 3, wherein the position of the communication portion with respect to the casing can be changed according to the position of the partition wall . The VOC collection device according to any one of claims 1 to 4, wherein the position of the communication portion with respect to the collection portion can be changed according to the position of the partition wall .

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