JP2011232300A - Monitoring system and monitoring method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a monitoring system capable of detecting an increase in concentrations of volatile organic compounds contained in the air without delay and capable of specifying a material which causes the increase in the concentrations of the volatile organic compounds.SOLUTION: A monitoring system comprises: a measurement device 2 for measuring concentrations of volatile organic compounds contained in the air which is a monitoring target at intervals of measurement time set in advance; a collection device 3 for sequentially collecting the volatile organic compounds contained in the air which is the monitoring target at intervals of collection time set in advance; a management device 4 for managing the volatile organic compounds sequentially collected by the collection device 3 in association with their respective collection time points and for specifying each of the volatile organic compounds collected by a collection tube in a measurement time zone including a measurement time point if the concentrations of the volatile organic compounds measured by the measurement device 2 is greater than or equal to a concentration set in advance; and an analysis device 5 for performing a qualitative and quantitative analysis on the each of the volatile organic compounds specified by the management device 4.

Description

  The present invention relates to a monitoring system and a monitoring method suitable for monitoring an organic compound contained in air.

  If air in a clean room for producing a semiconductor or a liquid crystal device is contaminated by a molecular or gaseous organic compound, the produced semiconductor or the liquid crystal device is affected, which is not preferable. For this reason, it is desired to measure the concentration of the organic compound contained in the air in the clean room and to take an appropriate measure when the concentration of the organic compound exceeds a preset concentration.

  A measuring device that measures the concentration of an organic compound in a clean room in real time is known. For example, a measuring device using a crystal resonator measures the concentration of the organic compound by determining the weight of the organic compound attached to the crystal resonator from a change in the resonance frequency of the crystal resonator. Since the crystal resonator is installed in a clean room and the change in the resonance frequency is constantly measured, this measuring device measures the concentration of the organic compound in real time (see, for example, Patent Document 1).

  There is also known an analyzer that qualitatively and quantitatively analyzes an organic compound contained in the air and analyzes the substance constituting the organic compound and the amount of the substance. The analyzer is called a gas chromatograph, and separates and purifies the organic compound contained in the air, thereby obtaining the substance constituting the organic compound and the amount of the substance.

JP 2000-180332 A

  However, the above-described measuring apparatus cannot perform qualitative and quantitative analysis of the measured organic compound. For this reason, it is not possible to specify a substance that causes an increase in the concentration of the organic compound only by the measuring device. On the other hand, the above-described analyzer cannot obtain an analysis result immediately. For this reason, an increase in the concentration of the organic compound cannot be detected without delay using only the analyzer.

  The present invention has been made in view of the above, and can detect an increase in the concentration of an organic compound contained in air without delay, and can also identify a substance that causes an increase in the concentration of an organic compound. The purpose is to provide a monitoring method.

  In order to solve the above-described problems and achieve the object, the present invention provides a measuring device that measures the concentration of an organic compound contained in air to be monitored at each preset measurement time, and a preset capture. A collection device that sequentially collects organic compounds contained in air to be monitored at each collection time, and an organic compound that is sequentially collected by the collection device is managed in association with the collection time, and the measurement device When the concentration of the measured organic compound is equal to or higher than a preset concentration, the management device that identifies the organic compound collected by the collection tube during the measurement time zone including the measurement time, and the management device identified And an analyzer for qualitative and quantitative analysis of organic compounds.

  Further, in the monitoring system according to the present invention, when the concentration of the organic compound measured by the measurement device is less than a preset concentration, the management device collects the organic compound collected by the collection tube during the measurement time zone. The collection device desorbs the organic compound specified by the management device.

  In addition, the present invention measures the concentration of the organic compound contained in the air to be monitored every preset measurement time, and also contains the organic compound contained in the air to be monitored every preset collection time Qualitative quantitative analysis of the organic compound collected by the collection tube during the measurement time zone including the measurement time when the concentration of the measured organic compound exceeds the preset concentration. Features.

  Further, the present invention is characterized in that, in the above monitoring method, when the measured concentration of the organic compound is less than a preset concentration, the organic compound collected in the measurement time zone is desorbed.

  Since the monitoring system according to the present invention measures the concentration of the organic compound contained in the air to be monitored at every preset measurement time, an increase in the concentration of the organic compound can be detected without delay. In addition, since the organic compound contained in the air to be monitored is collected sequentially for each predetermined collection time and managed in association with the collection time, the concentration of the measured organic compound is set in advance. When the concentration is higher than the concentration, it is possible to identify and qualitatively analyze the organic compound collected by the collection tube in the measurement time zone including the measurement time. Thereby, the substance causing the increase in the concentration of the organic compound can be specified.

  Since the monitoring method according to the present invention measures the concentration of the organic compound contained in the air to be monitored at every preset measurement time, the increase in the concentration of the organic compound can be detected without delay. Moreover, when the organic compound contained in the air to be monitored is collected at every preset collection time, and the measured concentration of the organic compound is equal to or higher than the preset concentration, the measurement time is included. Qualitative and quantitative analysis of organic compounds contained in the air collected by the collection tube during the measurement time zone is possible. Thereby, the substance causing the increase in the concentration of the organic compound can be specified.

FIG. 1 is a block diagram showing a monitoring system according to an embodiment of the present invention. FIG. 2 is a conceptual diagram showing the structure of the collection device shown in FIG. FIG. 3 is a flowchart showing the monitoring method according to the embodiment of the present invention. FIG. 4 is a diagram showing the concentration of the volatile organic compound measured by the measuring device. FIG. 5 is a diagram showing the concentration of the volatile organic compound measured by the measuring device. FIG. 6A is a diagram illustrating an analysis result of the volatile organic compound collected at A in FIG. 5. 6-2 is a figure which shows the analysis result of the volatile organic compound collected at the time of B of FIG. 6-3 is a figure which shows the analysis result of the volatile organic compound collected at the time of C of FIG. FIG. 7 is a time chart showing the relationship between the measurement time and the collection time and the relationship between the measurement time and the time required for analysis in the monitoring method according to the embodiment of the present invention. FIG. 8 is a diagram showing the concentration of the volatile organic compound obtained at the measurement time shown in FIG. FIG. 9 is a diagram showing an analysis result of the volatile organic compound collected at D in FIG. FIG. 10 is a diagram showing an analysis result of the volatile organic compound collected at E in FIG.

  Embodiments of a monitoring system and a monitoring method according to the present invention will be described below in detail with reference to the drawings. Here, a monitoring system and a monitoring method suitable for monitoring volatile organic compounds (chemical pollutants) contained in air in a clean room used for production or development of semiconductors and liquid crystal devices will be described as an example. However, the present invention is not limited to the above.

  FIG. 1 is a block diagram showing a monitoring system according to an embodiment of the present invention. As shown in FIG. 1, the monitoring system according to the embodiment of the present invention monitors a volatile organic compound contained in the air in a clean room, and includes a measuring device 2, a collecting device 3, a management device 4, and an analysis. A device 5 is provided.

  The measuring device 2 measures the concentration of a volatile organic compound (VOC) contained in air to be monitored in real time on-site (locally). The measuring device 2 can employ any device such as one using a crystal resonator or one using a photoionization detector, but in this embodiment, the measuring device 2 using a photoionization detector is used. Is adopted. Note that the measuring device 2 using the photoionization detector is equipped with an appropriate PID lamp because the measurable volatile organic compound differs depending on the type of PID lamp to be mounted (gas separation voltage).

  The measuring device 2 measures the concentration of the volatile organic compound contained in the air in the clean room at every preset measurement time, and outputs the measurement result to the management device 4. The measurement time can be arbitrarily set between 1 second and 30 minutes. The measurement time is the time from the time when the concentration is measured (measurement time) to the time when the concentration is measured next (measurement time), and is kept constant after the setting.

  The collection device 3 sequentially collects volatile organic compounds contained in air to be monitored.

  The collection device 3 introduces air in the clean room at every preset collection time, sequentially collects volatile organic compounds contained in the introduced air, and collects the collection time information and the collected volatilization. Information specifying the organic organic compound is output to the management device 4. The collection time can be arbitrarily set. The time required for the collection device 3 to collect air in the clean room is 1 minute to several minutes, and collection in a short time is possible. The collection time is the time from the start time of air introduction (collection time) to the next start time of air introduction (collection time), and is kept constant after setting.

  FIG. 2 is a conceptual diagram showing the structure of the collection device shown in FIG. As shown in FIG. 2, the collection device 3 has an introduction port 31 for introducing air to be monitored, and introduces air in the clean room from the introduction port 31. The collection device 3 includes a turntable 32. The turntable 32 is for continuously collecting air to be monitored, and a collection tube 33 is mounted at each position where the turntable 32 is equally divided in the circumferential direction. When the turntable 32 stops, the collection pipe 33 that introduces air to be monitored faces the introduction port 31, and the air in the clean room can be introduced into the collection pipe 33. Then, the air introduced into the collection tube 33 circulates through the collection tube 33.

  The collection tube 33 is filled with an adsorbent 34. The adsorbent 34 adsorbs volatile organic compounds contained in the air to be monitored, and the air to be monitored circulates in the adsorbent, so that the volatile organic contained in the air to be monitored. The compound is adsorbed. As the adsorbent 34, for example, a solid adsorbent such as Tenax-GR, Tenax-TA (trade name) is used.

  Volatile organic compounds adsorbed on the adsorbent 34 are desorbed from the adsorbent 34 by heat treatment. The time required for desorption of the volatile organic compound is about several seconds to 1 minute, and desorption in a short time is possible. In the case of qualitative quantitative analysis of the volatile organic compound in the analyzer 5, the volatile organic compound is desorbed by heat-treating the adsorbent 34. Also, when releasing the volatile organic compound adsorbed on the adsorbent 34, the adsorbent 34 is heat-treated to desorb the volatile organic compound. Thus, the adsorbent 34 from which the volatile organic compound has been desorbed can be reused.

  The collection device 3 outputs the collection time of the sequentially collected volatile organic compounds and information for specifying the collected volatile organic compounds to the management device 4. The information specifying the volatile organic compound is information on the collection tube 33 in which the volatile organic compound is adsorbed on the adsorbent 34, and for example, the volatile property collected by specifying the mounting position of the collection tube 33. Identify organic compounds.

  As shown in FIG. 1, a measuring device 2 and a collecting device 3 are connected to the management device 4, and concentration information of the volatile organic compound output from the measuring device 2 and the collecting information output from the collecting device 3. Collection time information and information for identifying the collected volatile organic compound are input.

  When the concentration of the volatile organic compound measured by the measuring device 2 is equal to or higher than a preset management concentration value, the management device 4 identifies the volatile organic compound collected in the measurement time zone including the measurement time. Is. The management device 4 collects at a time zone including the measurement time when the concentration of the volatile organic compound is compared with the management concentration value, and when the concentration of the volatile organic compound exceeds the management concentration value. And specifying means 42 for specifying the volatile organic compound.

  The comparison unit 41 compares the concentration information of the volatile organic compound input from the measurement device 2 with the preset management concentration value information. The management concentration value can be arbitrarily set, and the management device 4 determines that an abnormality occurs when the concentration of the volatile organic compound becomes equal to or higher than the management concentration value. Note that the management device 4 may issue a warning when it is determined to be abnormal.

  The specifying means 42 specifies the volatile organic compound collected in the measurement time zone including the measurement time when the concentration of the volatile organic compound input from the measuring device 2 is equal to or higher than the control concentration. The measurement time zone can be set arbitrarily, and the time zone before the measurement time, the time zone after the measurement time, the time zone before and after the measurement time, etc. can be set arbitrarily. Also, the time zone can be arbitrarily set.

  The analysis device 5 performs qualitative and quantitative analysis of the volatile organic compound specified by the management device 4, and obtains a substance constituting the volatile organic compound and the amount of the substance by separating and purifying the volatile organic compound. As the analyzer 5, a gas chromatograph or a gas chromatograph mass spectrometer is used.

  FIG. 3 is a flowchart showing the monitoring method according to the embodiment of the present invention.

  As shown in FIG. 3, when monitoring is started, the measurement device 2 starts measurement, and the collection device 3 starts collection.

  When the measurement device 2 starts measurement, the concentration of the volatile organic compound contained in the clean room air is measured every predetermined measurement time (step S1). Then, the density information obtained by the measurement is output to the management device 4.

  When the collection device 3 starts collecting, air in a clean room is introduced at every collection time set in advance, and volatile organic compounds contained in the introduced air are sequentially collected (step S2). Specifically, air introduced from the clean room is introduced into the collection tube 33, and a volatile organic compound contained in the introduced air is adsorbed to the adsorbent 34 filled in the collection tube 33. The collection tube 33 in which the volatile organic compound is adsorbed by the adsorbent 34 is stored, and the collection time information and information for specifying the volatile organic compound (collection tube 33) are output to the management device 4. The time required for collection is short as described above, and can be collected within the collection time (the time from the collection time to the next collection time).

  The management device 4 compares the concentration information of the volatile organic compound input from the measuring device 2 with preset management concentration value information. Then, as shown in FIG. 4, when the concentration of the volatile organic compound is less than the control concentration, it is determined to be normal, and as shown in FIG. Judgment is made (step S3).

  Moreover, when the density | concentration of a volatile organic compound is more than a management density | concentration value, the volatile organic compound (collection pipe | tube 33) collected in the measurement time slot | zone containing the measurement time is specified (step S4).

  The analysis device 5 performs qualitative and quantitative analysis of the volatile organic compound specified by the management device 4 (step S5). Specifically, the specified collection tube 33 is overheated to desorb the volatile organic compound from the adsorbent 34 in the collection device 3 and supply it to the analysis device 5. The analysis device 5 obtains the substance constituting the volatile organic compound and the amount of the substance by qualitative and quantitative analysis of the volatile organic compound introduced from the collection device 3. The time required for desorption of the volatile organic compound is short as described above, and can be desorbed within the collection time (from the collection time to the next collection time).

  FIG. 5 shows an example where the concentration of the volatile organic compound is equal to or higher than the control concentration value at the time of A, B, and C. When the volatile organic compound collected at the time of A, B, and C is qualitatively quantitatively analyzed, the analyzer can obtain the analysis result shown in FIG. The analysis results shown in FIG. 6-1 show the substances constituting the volatile organic compounds collected at A and the amount of the substances, and the analysis results shown in FIG. 6-2 show the volatiles collected at B. The substance which comprises an organic compound and the amount of the substance are shown. Moreover, the analysis result shown in FIG. 6-3 shows the substance which comprises the volatile organic compound collected at the time of C, and its substance quantity. The analysis result thus obtained is qualitatively quantitatively analyzed by analyzing it using a calibration curve obtained in advance with a standard substance.

  On the other hand, if the concentration of the volatile organic compound is less than the control concentration value, the volatile organic compound (collection tube) collected during the measurement time zone is specified (step S6), and the volatile organic compound is removed. Release. Specifically, the volatile organic compound is desorbed from the adsorbent by heat-treating the adsorbent (step S7).

  FIG. 7 is a time chart showing the relationship between the measurement time and the collection time and the relationship between the measurement time and the time required for analysis in the monitoring method according to the embodiment of the present invention. Moreover, FIG. 8 is a figure which shows the density | concentration of the volatile organic compound obtained at the measurement time shown in FIG. 9 is a diagram showing an analysis result (gas chromatogram) of a volatile organic compound collected at D in FIG. 8, and FIG. 10 is a diagram showing an analysis result (gas chromatogram) at point E in FIG.

  In the example shown in FIG. 7, the measurement time (the time from the measurement time to the next measurement time) and the collection time (the time from the collection time to the next collection time) are set to 20 minutes. Each time the concentration of volatile organic compounds contained in the clean room air is measured and the volatile organic compounds contained in the air introduced from the clean room are collected. In the example shown in FIG. 7, the measurement time and the collection time are the same time, and the measurement time and the collection time are the same time, but the measurement time and the collection time are set to be the same. There is no need. For example, the measurement time may be set shorter than the collection time, or may be set longer than the collection time.

  As shown in FIG. 8, when the concentration of the volatile organic compound measured at D time (1:00) is equal to or higher than the control concentration value, it is captured at the measurement time zone including D time, for example, at D time. The collected volatile organic compounds are identified, and the volatile compounds are qualitatively and quantitatively analyzed. Specifically, the volatile organic compound is collected from the adsorbent 34 by identifying the collection tube 33 that has collected the volatile organic compound during D, and overheating the adsorbent 34 filled in the collection tube 33. The compound is eliminated and qualitative quantitative analysis is performed. In the above-described example, the volatile organic compound collected at D when the concentration of the volatile organic compound is equal to or higher than the control concentration is qualitatively quantitatively analyzed, but collected before D (for example, 0:40). Qualitative quantitative analysis of volatile organic compounds is also possible. Further, the time required to desorb the volatile organic compound from the adsorbent 34 is a short time of several seconds to 1 minute, and the volatile organic compound can be desorbed from the adsorbent 34 within the collection time. Is possible.

  As shown in FIG. 9, from the analysis result (gas chromatogram), the substance which comprises a volatile organic compound, and its substance quantity are obtained.

  In addition, as shown in FIG. 8, when the concentration of the volatile organic compound measured at E time (1:40) is equal to or higher than the control concentration value, it is captured in the measurement time zone including E time, for example, at E time. The collected volatile organic compounds are identified, and the volatile organic compounds are qualitatively and quantitatively analyzed.

  As shown in FIG. 10, from the analysis result (gas chromatogram), the substance constituting the volatile organic compound and the quantity of the substance are obtained.

  Further, as shown in FIG. 8, the concentration of the volatile organic compound measured at F time (2:00) is also equal to or higher than the control concentration value, but the concentration of the volatile organic compound at the previous measurement time (E time) Since the concentration is almost the same, it can be assumed that the analysis result of the volatile organic compound collected at F and the analysis result of the volatile organic compound collected at E are substantially the same. For this reason, you may abbreviate | omit the qualitative quantitative analysis of the volatile organic compound collected at the time of F. Thus, by omitting the qualitative quantitative analysis under certain conditions, the work load required for the qualitative quantitative analysis is reduced. The omission of the qualitative quantitative analysis may be performed manually or by a program executed when a certain condition is satisfied.

  The monitoring system and the monitoring method according to the embodiment of the present invention described above measure the concentration of the volatile organic compound contained in the air in the clean room at every predetermined measurement time. The rise can be detected without delay. In addition, since the volatile organic compounds contained in the air in the clean room are collected sequentially for each preset collection time and managed in association with the collection time, the measured concentration of the volatile organic compounds is set in advance. When the concentration exceeds the set level, the volatile organic compounds collected during the measurement time period including the measurement time can be specified and qualitative quantitative analysis can be performed. Thereby, the increase in the concentration of the volatile organic compound contained in the air can be detected without delay, and the substance that causes the increase in the concentration of the volatile organic compound can be specified.

  Further, when the concentration of the volatile organic compound measured by the measuring device 2 is less than the control concentration value, the volatile organic compound collected during the measurement time zone is desorbed (cleaned) from the adsorbent 34, so that the adsorbent 34 can be reused.

  In addition, although the monitoring of the clean room was explained, it is not limited to this, monitoring of volatile organic compounds (VOC) in the indoor environment, monitoring of volatile organic compounds (VOC) in the work environment, generated from soil It is also applicable to monitoring of volatile organic compounds (VOC).

DESCRIPTION OF SYMBOLS 2 Measuring apparatus 3 Collection apparatus 31 Introduction port 33 Collection pipe 34 Adsorbent 4 Management apparatus 41 Comparison means 42 Identification means 5 Analysis apparatus

Claims (4)

A measuring device that measures the concentration of an organic compound contained in the air to be monitored at each preset measurement time; and
A collection device that sequentially collects organic compounds contained in air to be monitored for each collection time set in advance;
The organic compound sequentially collected by the collection device is managed in association with the collection time, and the measurement including the measurement time is performed when the concentration of the organic compound measured by the measurement device is equal to or higher than a preset concentration. A management device that identifies the organic compounds collected by the collection tube during the time period; and
A monitoring system comprising: an analyzer for qualitative and quantitative analysis of the organic compound identified by the management device.   The management device specifies the organic compound collected by the collection tube during the measurement time zone when the concentration of the organic compound measured by the measurement device is less than a preset concentration, and the collection device is The monitoring system according to claim 1, wherein the organic compound identified by the management device is desorbed. While measuring the concentration of the organic compound contained in the air to be monitored at each preset measurement time, and sequentially collecting the organic compound contained in the air to be monitored at each preset collection time ,
A monitoring method characterized by qualitative and quantitative analysis of an organic compound collected by a collection tube during a measurement time zone including the measurement time when the concentration of the measured organic compound is equal to or higher than a preset concentration.   4. The monitoring method according to claim 3, wherein when the measured concentration of the organic compound is less than a preset concentration, the organic compound collected in the measurement time zone is desorbed.

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