JP2004233061A - Continuously enriched gas sampling device by nebulizer / denuder connection, gas analyzer incorporating the gas sampling device, and analysis method - Google Patents

Abstract

An object of the present invention is to provide a gas sampling apparatus for continuously enriching a target component in a gas sample by bringing it into contact with an absorbing liquid, and a high-precision on-site analysis system combining the gas sampling apparatus and a portable detection apparatus.
A required amount of a gas sample sucked by an air pump (2) through an air filter (1) is discharged to a nebulizer (4) by a gas flow meter (3). The absorbing liquid 6 supplied by the liquid sending pump 5 and sprayed into fine droplets by the gas sample by the nebulizer flows along the inner wall of the denuder tube 7 and the surface of the filler with the gas sample while repeating contact, and enters into the absorbing liquid. The target component is concentrated and collected. Subsequently, the gas sample and the absorption liquid reach the gas-liquid separation column 8, are inertially separated, the absorption liquid which concentrates and collects the target component is collected as the measurement sample solution 9 of the target component detection device, and the remaining gas sample is exhausted. Is done. The target component concentrated and collected in the absorbing solution is detected by the detection device. A series of analytical operations of concentration collection and detection of the target component are continuously performed.
[Selection diagram] Fig. 1

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an apparatus for continuously concentrating and collecting components contained in a gas sample, and a method and an apparatus for continuously analyzing components contained in a gas sample by connecting the continuous gas enrichment collecting apparatus and a detector. About.
[0002]
[Prior art]
When measuring contaminants in indoor air, the sampling method is to collect air in a sampling bag or liquid or solid collecting material through a certain amount or for a certain period of time, and perform simple measurement on site or in the laboratory after collection. The mainstream method is to carry out complicated operations such as extraction and concentration by taking them back to the laboratory and measuring them with a large analytical instrument such as a high-performance liquid chromatograph (HPLC) or a gas chromatograph / mass spectrometer (GC / MS).
[0003]
For example, when measuring the formaldehyde concentration in indoor air, a gas sample is collected at a site to be measured through a cartridge filled with a DNPH solution impregnated collecting agent for a certain period of time, then returned to a place where experimental facilities are located and extracted with acetonitrile. Then, the amount of formaldehyde is measured by a high performance liquid chromatograph (see Japanese Industrial Standard JIS K0303 or the like), or by adsorption using a diffusion type gas monitor called a passive sampler, and similarly measured by solvent extraction-high performance liquid chromatograph.
[0004]
In addition, since head and neck cancer and esophageal cancer have a poor prognosis and are regarded as “refractory cancer”, extracting high-risk groups of these cancers is urgently required in preventive medicine. Recently, a method of screening high-risk groups of these cancers easily and with high sensitivity has been found by measuring the acetaldehyde concentration in the breath after a small amount of alcohol load. Sampling bag collection and gas chromatography have been found as methods for measuring these. It has been researched.
[0005]
[Problems to be solved by the invention]
All of the above-mentioned conventional techniques measure the average concentration of the target component within the collection time, and one measurement result is obtained by one collection operation. For this reason, when performing concentration measurement over time with the conventional technology, the same collection operation must be performed at regular intervals, and the collection equipment requires only one collection agent per measurement and the measurement point. And is not suitable for continuous measurement.
[0006]
Furthermore, in the conventional technology, when the concentration of the target component is low, it is necessary to lengthen the collection time.Moreover, in most cases, the cartridge or the like that has collected the target component is returned to the laboratory or the like, and pretreatment such as solvent extraction is performed. After performing the above, it is difficult to obtain the measurement result on the spot where the sample was taken, since it takes a long time from the sampling to the final measurement result to measure the target component with various analyzers. there were.
[0007]
All of the simple measurement methods that are currently in practical use conform to the guidelines and regulation values for indoor air concentrations set by various ministries and agencies such as the Ministry of Health, Labor and Welfare. According to patients (sick house, chic building, etc.), even a concentration less than one-tenth of each regulation value often causes serious symptoms. Therefore, these simple measuring methods and devices have insufficient capacity.
[0008]
In addition, high-risk group screening tests for head and neck and esophageal cancer by measurement of acetaldehyde in exhaled breath have not yet been put to practical use, and there is a need for the development of a measurement device that can be easily tested for daily human dogs and health examinations. ing.
Therefore, when performing precise concentration measurement, the conventional method may not be able to accurately determine the concentration of the target substance in indoor air, which tends to vary depending on the method of collecting human breath and the environment such as solar radiation, heating, and ventilation. This is an obstacle to taking policies and measures for indoor environment.
[0009]
In view of the aforementioned problems, the present invention provides a method capable of continuously concentrating and collecting a target component in a gas sample such as room air and human expiration, and a compact, portable and convenient gas collecting device for implementing the method. It is an object of the present invention to provide a system capable of performing, in a short time, continuously from sampling to concentration measurement on the spot by connecting to various portable detection devices.
[0010]
[Means for Solving the Problems]
In the method of the present invention, the gas sample sucked by the pump is sent to the nebulizer, and the gas sample is ejected from the nozzle having a thinned tip. When the gas sample is discharged from the nebulizer nozzle tip, the gas sample is sucked by being decompressed inside the nozzle. Or, it is brought into contact with the absorbing liquid supplied at a constant flow rate by a liquid sending pump for supplying the absorbing liquid, and the absorbing liquid is formed into fine droplets, and the inner wall of the denuder pipe connected to the nebulizer and the filling for collection in the pipe are formed. Spray on the material surface. Due to the flow of the gas sample, the fine droplet-shaped absorbing liquid in contact with the gas sample moves on the surface of the collecting filler inside the denuder tube while dissolving the target component, and the gas-liquid connected to the outlet of the denuder tube It is sent to the separation tube. The absorption liquid is separated from the gas by inertia separation in the gas-liquid separation column, and the gas sample after the collection of the target component is exhausted. By continuously collecting the absorbing liquid from the gas-liquid separation column, the target component can be continuously concentrated and collected.
[0011]
Further, since the flow rate of the absorbing liquid is smaller than the suction amount of the gas sample, the target component having a low concentration can be continuously concentrated and collected at a high magnification. Taking formaldehyde in room air as an example, a suction rate of 2.0 L / min. On the other hand, the flow rate of the absorbing solution H2O was 0.1 mL / min. , A stable collection efficiency of 98% or more was obtained, and the concentration ratio at this time was 20000 times in volume ratio.
[0012]
Further, by continuously connecting and directly introducing the absorbing liquid that has collected the target component by connecting to a portable detection device, continuous concentration measurement of the target component can be performed on the spot. Taking formaldehyde in indoor air as an example, a detection limit of 0.001 ppm can be obtained by the method of the present invention in which a flow injection analyzer (FIA) is connected as a detector, against the guideline value of 0.08 ppm of the Ministry of Health, Labor and Welfare. ing.
[0013]
In addition, by changing the type of the absorbing solution and the portable detecting device, such as applying the absorbing solution to an organic solvent such as methanol, changing the detecting device to a gas chromatograph, and applying it to many volatile organic compounds (VOC components), The method according to the present invention can be applied as a high-precision and high-sensitivity monitoring device for many chemical substances in the field.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, embodiments of the present invention will be described specifically and in detail with reference to the drawings.
FIG. 1 is a configuration diagram of a gas sampling device according to one embodiment of the present invention.
The gas sample containing the target component is sucked by the air pump 2 from the gas sampling port 1a of the open face type air filter 1. Although not shown, the air filter 1 is provided with a mesh sheet for removing dust and dirt from the gas sample as a filter. The material of the mesh sheet is a target component and a fluororesin that does not adsorb moisture, and the target component is Use a mesh size that will not collect not only gaseous but also particulate mist. The gas sample collected at the suction port 2a of the air pump 2 is sent from the air pump discharge port 2b to the gas flow meter 3, and the flow rate of the gas sample is adjusted to a predetermined sample collection amount.
[0015]
Subsequently, the gas sample is sent to the nebulizer 4, where the absorbing liquid supplied at a constant flow rate by the liquid sending pump 5 is formed into fine droplets, and sent to the denuder tube 6 together with the absorbing liquid. The target component is collected in the absorbing liquid while the droplet moves while contacting. The fine droplet-shaped absorbing liquid sprayed from the nebulizer 4 is directly sprayed on the inner wall of the denuder and the surface of the denuder filler.
[0016]
After that, the gas sample and the absorbing liquid reach the gas-liquid separation column 7 and are separated into a collected liquid in which the absorbing liquid has collected the target component by inertial separation and an exhaust gas in which the target component has been collected and removed from the gas sample, The collected liquid is collected for detecting the target component, and the exhaust gas is exhausted. Here, the absorption liquid is water having a high solubility for the target component, an inorganic acid solution, an alkali solution, a buffer, an organic solvent, or water containing a compound having a reactive functional group specifically with the target component, or an organic solvent. , Respectively, depending on the target component and the use environment.
[0017]
The air pump 2 is an air pump for both suction and discharge, capable of continuous stable operation for a long time, and does not use oil, and has a flow rate of 0.5 to 6 L / min. Use the one with the degree obtained. The air pump 2 has a two-flow path. When the exhaust sample gas after the collection of the target component contains a chemical substance which may cause indoor air pollution due to the absorbing liquid component, the denuder for removal is further used. When installing a tube, use a separate flow path for collecting the target component.
[0018]
The flow meter 3 has a needle valve and can adjust the flow rate, and has a flow rate range of 0.5 to 5 L / min. Use something of the order. If the exhaust sample gas after collection of the target component contains a chemical substance that may cause indoor air pollution due to the absorption liquid component, and if a denuder tube for removal is equipped, use a separate flow meter. Is installed.
[0019]
The liquid sending pump 5 has a flow rate of 0.1 mL / min. Has a performance that can be obtained stably for a long time, and is not shown for sending the absorbing liquid for collecting the target component, but is not shown, but is used for collecting the collected liquid after collecting the target component as necessary. Install another pump. Alternatively, a liquid feed pump having two channels is used. Alternatively, the inside of the nebulizer is depressurized with the discharge of the gas sample containing the target component from the nebulizer outlet, and the absorption liquid may be supplied to the nebulizer without using the liquid feed pump by using a phenomenon in which the absorption liquid is sucked. .
[0020]
Although not shown, the absorbing liquid supply container for supplying the absorbing liquid by the liquid sending pump 5 has a feature that the target component is not eluted with respect to the absorbing liquid described in the preceding item, and that it becomes other indoor air pollutants. It is a material that does not dissolve chemical substances and does not cause a chemical reaction with the absorbing solution described in the preceding paragraph and does not hinder the transport and storage of the absorbing solution. It is made of fluororesin such as PTFE, reinforced glass, PE, PP, etc. Synthetic polymers or those obtained by processing their inner surfaces with fluororesin are used. In addition, when using an absorbing solution that may be denatured during storage due to contact with the atmosphere or interfere with collection of the target component or measurement of the concentration of the target component with a detector, the internal volume will decrease as the solution decreases. Use a decreasing volume container.
[0021]
The absorption liquid supply container is provided with an open / close cock so that the absorption liquid does not flow out except during operation. The opening and closing cock is processed and attached to the lid of the absorbing liquid supply container so that the absorbing liquid container can be easily replaced. Further, a liquid supply tube for supplying the liquid supply pump 5 to the liquid supply pump 5 is attached to the lid of the container for supplying the liquid supply.
[0022]
The absorption liquid supply tube has no elution of the target component with respect to the absorption liquid described in the preceding paragraph, and also has no elution of other chemicals that may be indoor air pollutants. Fluorine resin such as PTFE and PFA, or other synthetic polymers, glass, metals and alloys are used. Each is selected according to the target component, the absorption liquid to be used, and the use environment.
[0023]
FIG. 2 shows a nebulizer used to increase the contact area between the gas sample and the absorbing liquid to improve the collection efficiency of the target component in the absorbing liquid, and to convert the absorbing liquid into fine droplets. The nebulizer used in the present invention is a cross-flow nebulizer (a) in which the tip of a gas sample ejection nozzle 4a and the tip of an absorption liquid ejection nozzle 4b are close to each other at right angles, and spray fine droplets from a nebulizer outlet 4c. A coaxial nebulizer (b) in which an absorbing liquid discharging nozzle 4b is installed in the same direction inside a gas sample ejecting nozzle 4a and sprays the absorbing liquid as fine droplets by the flow of the gas sample, or The ultrasonic oscillator 4d is installed in a liquid reservoir provided in the middle of the supply tube, and the absorbing liquid is atomized by ultrasonic waves, and the atomized absorbing liquid is sprayed from the nebulizer outlet 4c by the flow of the gas sample. An ultrasonic nebulizer (c).
[0024]
The main body of the cross flow nebulizer is made of fluororesin such as PTFE or other synthetic polymer, or reinforced plastic such as FRP, and the material of the sample gas and the absorbing liquid injection nozzle is quartz, Pyrex (registered trademark) and other various glasses, nickel, etc. Metals and alloys such as stainless steel, platinum and copper, ceramics such as alumina, and synthetic polymers (synthetic resins) such as PTFE and other fluororesins. You. The material of the coaxial nebulizer is quartz, Pyrex glass (registered trademark), a fluororesin such as PTFE or PFA, or a synthetic polymer such as PP, PEEK, PMO, or nylon.
[0025]
These nebulizers are widely used when introducing a solution sample into a device in plasma emission spectrometry (ICP) or mass spectrometry (MS), and the nebulizer used in these devices has a narrow nebulizer outlet. Therefore, the nebulizer used in the gas sampling device of the present invention is more suitable for injecting a gas sample than the nebulizer used in the above-described ICP and MS. The nozzle, the absorbing liquid discharge nozzle and the outlet of the nebulizer have a large diameter, the flow velocity at the outlet is low, and the absorbing liquid is not a fine mist but a fine droplet. When the absorbing liquid is in the form of fine mist, the gas sampling apparatus of the present invention aggregates the mist of absorbing liquid into relatively large droplets and flows through the denuder tube. The contact area between the sample and the absorbing solution is reduced, and as a result, the collection efficiency is not improved. In the nebulizer used in the present invention, the absorbing liquid does not form a mist and becomes fine droplets, so that the absorbing liquid does not aggregate and flows as fine droplets in the denuder tube together with the gas sample.
[0026]
FIG. 3 is an example of a denuder tube incorporated in the gas sampling device of the present invention. The denuder tube 6 is made of various glasses such as quartz, borosilicate glass, and Pyrex glass (registered trademark), or a transparent or translucent synthetic polymer such as a fluororesin, and reacts or adsorbs with the target component and the component in the absorbing solution. The inner wall is made of a thin tube having a smooth inner diameter of 1 to 20 mm and a length of 10 to 2000 mm. The shape is any of a straight tube, a loop, and a coil. Each is selected according to the target component, the absorption liquid to be used, and the use environment.
[0027]
In order to increase the contact between the gas sample and the absorbing liquid, quartz, glass, various silicate compounds, metals, alloys, ceramics, fluoroplastics, carbon, or other synthetic polymers are placed in the denuder tube depending on the target components. The filler 6a which has been processed into fibrous or granular form or a composite of two or more of these forms into fibrous or granular form is filled or adhered to the inner wall of the denuder pipe. Depending on the target component, the inner surface of the filler is chemically roughened using an inorganic acid such as hydrofluoric acid or sulfuric acid, an alkaline solution such as sodium hydroxide, an organic solvent, or physically roughened by heat or cutting. . Alternatively, there is a case where the above-mentioned filler is not used only with a thin tube.
[0028]
As described above, the inner wall of the denuder tube is smooth, but if necessary, the inner surface of the denuder tube is chemically treated using an inorganic acid such as hydrofluoric acid or sulfuric acid, an alkaline solution such as sodium hydroxide, or an organic solvent. Roughened by heat or by physical methods such as cutting. Alternatively, after the inner surface of the denuder tube has been roughened, the above-mentioned filler is adhered, and the absorbing liquid and the gas sample, which have formed fine droplets on the inner surface of the denuder tube and the surface of the filler, move while repeating contact with the target component. Is efficiently collected in the absorbing solution. Alternatively, the target component in the gas sample is first captured on the surface of the filler, and then captured in the absorbing solution by the flow of the absorbing solution.
[0029]
FIG. 4 shows an example of a gas-liquid separation cylinder for inertial separation of a gas sample from which a target component has been collected and removed and an absorbing solution having collected the target component. The main body 7 of the gas-liquid separation tube is a tube made of a synthetic polymer such as quartz, glass or fluororesin, and has a connection port 7a for the outlet of the denuder tube in the lower half, and a gas sample exhaust tube at the upper end of the tube. It has an L-shaped connector 7b for connection, and a connector 7f for connecting a collection liquid collection tube at the lower end, and performs gas-liquid separation by inertial separation. Separation by inertia separation of water, inorganic acid solution, alkaline solution, buffer solution, or organic solvent with extremely low volatility, or water or organic solvent containing a compound having a functional group that specifically reacts with the target component When the amount contained in the exhaust gas sample is small and the risk of becoming a new indoor air pollutant is extremely low, activated carbon is added to the tip of the gas sample exhaust tube 7c connected to the upper end of the gas-liquid separation tube. The exhaust air filter holder 7e filled with the air filter 7d is mounted.
[0030]
Although not shown in the figure, the inert gas separation with the gas-liquid separation tube alone has a high risk of releasing new indoor environmental pollutants into the exhaust gas sample. When water or an organic solvent containing a compound having a functional group that reacts with is used as an absorbing solution, a column filled with a solid trapping material such as activated carbon, silica gel, inorganic silicate, or alumina at the tip of a sample gas exhaust tube, Alternatively, a solid or liquid having a functional group that specifically reacts with the absorption liquid component is used as it is or is supported on the surface of the solid collecting material to form a collecting material, which is passed through a column filled with the collecting material and discharged into a room. Alternatively, another denuder tube is connected to absorb and remove the absorbent component in the exhaust sample gas by another harmless collection solution, and then exhausted through another gas-liquid separation tube.
[0031]
FIG. 5 shows an embodiment of a gas analyzer combining a gas sampling device and a detection device according to the present invention, and is a configuration diagram of a chain aldehyde analyzer in room air.
The gas sample containing the target component sucked through the air filter 1 is introduced into the gas sampling device 8, and the target component is concentrated and collected in pure water (H2O), which is an aldehyde absorption liquid supplied from the absorption liquid supply container 10. Is done. The absorption solution obtained by concentrating and collecting the target component is used as a sample solution in a detection device 9 such as a flow-type injection analyzer (FIA) such as a chain aldehyde analyzer such as a PFA / NO improved type manufactured by FIA Instruments Inc. The pure water branched from the absorption liquid supply container 10 also serving as the absorption liquid of the target component of the pure water is sent to the FIA flow line as a carrier solution.
[0032]
The sample solution flowing together with the carrier solution is automatically mixed with the reagent for chain aldehyde detection (Schiff reagent containing an acetate buffer) supplied from the reagent solution supply container 11 in the FIA, heated, reacted, detected, and used for data processing. The data processing is performed by the personal computer 12, and the result is displayed and the data is stored.
[0033]
In addition, the remaining target component collection concentrated solution obtained by collecting the required amount of the sample solution for the required amount of FIA measurement from the gas sampling device 8 and the carrier solution of the FIA, the reagent solution, and the sample solution after the reaction with the reagent are used as waste liquid. After most of the organic substances contained in the waste liquid are removed through a waste liquid treatment column 13 filled with a solid trapping material such as activated carbon, the waste liquid is collected in a waste liquid tank 14. These steps are automatically and continuously repeated to enable long-term automatic monitoring.
[0034]
Although not shown, the FIA is equipped with a column for separating a hydrophilic compound used in liquid chromatography (LC) (eg, Shodex RSpack DE 413), so that individual chain aldehydes such as formaldehyde and acetaldehyde can be obtained. Can be separated and detected.
[0035]
Although not shown, these are housed in one portable table to be a portable type, so that on-site concentration and collection of the target component in the gas sample, analysis of the target component, data processing, and waste liquid treatment can be performed. It is a system that can automatically and continuously perform all the processes necessary for the analysis of the system. As the portable detection device 9 connectable to the gas sampling device 8, in addition to the above-mentioned FIA, GC, GC / MS, HPLC including IC, UV-VIS, fluorimeter, FT-IR, pH meter, conductivity Includes a degree meter, an automatic titrator, and the like.
[0036]
Further, although not shown, a human breath collection container is connected between the air filter 1 and the gas sampling device 8 to provide a high-risk group simple screening test device for head and neck cancer and esophageal cancer during mass screening. Become. As a method of breath sampling, for example, a gas sampling container (Tedlar bag or the like) having a known capacity (0.25 to 1 L) has a variable capacity having an entrance with an opening / closing cock and an exit with an opening / closing cock on the opposite side of the entrance. Use a container. With this gas sampling container, human breath is sampled after ingesting a certain amount of alcohol. The above-mentioned gas sampling container, from which exhaled air is collected, is connected to the middle of the air suction tube of the above-mentioned gas sampling device, the cock is opened, and the collected exhaled air is introduced into the gas sampling device through the air.
The acetaldehyde in the exhaled breath is concentrated and collected in an absorbing solution (water) by a gas sampling device. The acetaldehyde in the concentrated and collected absorbent is quantified by FIA or GC, and the amount of acetaldehyde in the exhaled air is determined from the determined formaldehyde concentration in the absorbent and the amount of exhaled air (the capacity of the gas sampling container).
[0037]
The gas sampling device 8 is provided with a variable-length column that can fix the air filter 1 at an arbitrary height. A gas sampling tube from the air filter 1 to the gas sampling device 8 is made of a synthetic resin tube or a rubber tube including a fluororesin such as PFA or PTFE, or a quartz or glass tube. Instead, use one with high water repellency. Each is selected according to the target component, the absorption liquid to be used, and the use environment. The length of the gas sampling tube is 2 m from the outer wall of the gas sampling device, and a hook or the like around which the gas sampling tube is wound is provided on the outer wall of the gas sampling device so that the tube can be used at an arbitrary length. (Reference: Ministry of Health, Labor and Welfare Indoor Environment Guideline: 0.6-1.5 m above the floor, Ministry of Land, Infrastructure, Transport and Tourism floor material; 0.3 m above the floor)
[0038]
The sample introduction from the gas sampling device 8 to the detection device 9 is used when the detection device 9 has an automatic introduction function. However, when the function is not provided, an autosampler (sample automatic introduction) adapted to the detection device 9 is used. Device) into the system. The autosampler is provided with a function of collecting a collected liquid of the target component from the gas sampling device and a function of automatically injecting the sample into the detection device 9. If necessary, an additional pump for collecting the target component collected liquid is added to the gas sampling device. When incorporating the sample automatic introduction device separately, it is linked with the data processing.
[0039]
The sample waste liquid and the reagent waste liquid from the detection device 9 are collected into the aqueous system and the organic solvent system, respectively, after collecting the remaining amount of the collected liquid after the necessary amount is introduced from the gas sampling device 8 to the detection device 9. The waste liquid tank 14 may be made of a material that is not affected by these waste liquids. If necessary, take measures to prevent falls and overflow. Among the waste liquids, aqueous waste liquids include target components such as activated carbon and inorganic silicates, and compounds having a functional group that specifically reacts with the target components contained in the absorbing solution. Through a drainage treatment column 13 filled with a solid that adsorbs a substance or the like that has a high risk of causing the harm, and is rendered harmless and collected in a waste liquid container.
[0040]
The detoxified aqueous effluent can be disposed of in a general household drain. However, if reagents containing harmful or toxic substances are used even in aqueous wastewater, do not dispose of them until it is confirmed that these substances are not contained in the wastewater or that they are below the legal standard values. If these substances are detected at or above the reference value, they must be processed separately, such as entrusting them to a specialist, and then discarded. It is necessary to pay attention to this because the regulation value differs in each local government.
[0041]
All organic solvent waste liquids are collected in a waste liquid container and entrusted to a specialist. The waste liquid collection container should be in direct contact with indoor air using an air filter containing activated carbon to prevent waste liquid from being newly polluted in the indoor environment due to volatilization of the target component, solvent and reagents contained therein during use. Prevent part from being released by volatilization.
[0042]
【The invention's effect】
The gas sampling apparatus of the present invention is to continuously contact a gas sample containing a target component and an absorbent containing a compound having a large solubility in the target component or a functional group that specifically reacts with the target component. In principle, the target component is concentrated and collected in the absorbing solution.Since it is simple in principle, the target component in the gas sample is continuously captured at high magnification in a small amount of absorbing solution on site. Collection and concentration are possible. By changing the collection conditions such as the type of absorbing liquid, the flow rate ratio to the gas sample, and the type of denuder filling material that is the gas-liquid contact part with one gas sampling device, chain aldehydes in indoor air, Not only acetaldehyde, but also VOC (volatile organic compound) components such as aromatic or chain hydrocarbons, halogenated hydrocarbons, plasticizer components such as ester compounds, and termite and agricultural chemical components such as chlorpyrifos. It can be applied to chemicals called indoor air pollutants.
[0043]
To analyze a target component in a gas sample with high accuracy, concentrate and collect the gas sample through a solid or liquid collecting material for a long time as in the conventional gas sampling method, and then bring it back to the laboratory to elute and concentrate. In addition to the need for complicated operations, the time required for analysis is greatly reduced, and labor costs and energy costs are significantly reduced.In addition, according to the gas sampling apparatus of the present invention, since the principle is simple, the preprocessing operation is Factors that lower the analysis accuracy, such as systematic errors and individual errors, are greatly reduced, and improvement in the analysis accuracy is expected. In addition, by greatly reducing the types and amounts of reagents used in the pretreatment process, the generation of new indoor environmental pollutants and wastes due to the analysis operation are reduced, which can greatly contribute to energy problems and environmental problems. .
[0044]
Furthermore, by combining it with a portable detection device, it is possible to perform on-site high-precision real-time monitoring of target components at low cost, and to perform on-site high-accuracy analysis of the causative substances of sick buildings. Measures can be taken to meet the actual situation, and this is an effective means for providing comfortable living spaces.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a gas sampling device according to an embodiment of the present invention.
FIGS. 2A and 2B are three examples of a nebulizer incorporated in the gas sampling apparatus of the present invention, wherein FIG. 2A is a cross-flow type nebulizer in which a gas sample ejection nozzle and an absorbent ejection nozzle are positioned at right angles, and FIG. A coaxial nebulizer in which an absorbing liquid discharge nozzle is installed in the same direction in a gas sample injection nozzle, and (c) forms an absorbing liquid mist by an ultrasonic oscillator installed in an absorbing liquid storage, and An ultrasonic nebulizer that discharges a mist-like absorbing liquid by a flow.
FIG. 3 is an embodiment of a denuder tube incorporated in the gas sampling device of the present invention.
FIG. 4 is an embodiment of gas-liquid separation or the like incorporated in the gas sampling device of the present invention.
FIG. 5 is a configuration diagram of a chain aldehyde analyzer in room air in one embodiment of the gas analyzer combining the gas sampling device and the detection device of the present invention.
[Explanation of symbols]
1 Air filter
1a Gas sampling port
2 air pump
2a Air pump suction port
2b Air pump outlet
3 Gas flow meter
4 Nebulizer
4a Gas sample injection nozzle
4b Absorbing liquid discharge nozzle
4c Nebulizer outlet
4d ultrasonic oscillator
5 Liquid sending pump
6 Denuder tube
6a Filamentous or granular filler or adhering material to inner wall of denuder pipe
7 Gas-liquid separation cylinder
7a Connection for outlet of denuder pipe
7b L-shaped connector for connecting exhaust tube
7c Exhaust tube
7d Air filter with activated carbon
7e Exhaust air filter holder
7f Connector for collecting liquid collection tube connection
8 Gas sampling equipment
9 Detector
10 Absorption liquid of gas sampling device and pure water as FIA carrier solution
11 Reagent solution used for measurement
12. Laptop PC for data processing
13 Wastewater treatment column
14 Measurement waste liquid recovery tank

Claims (16)

Gas sampling for continuously enriching and collecting the target component in the absorbing solution by bringing the gas sample containing the component to be measured into contact with the absorbing solution that has a large dissolving power or reacts selectively with the component to be measured. apparatus. The gas sample is room air, outdoor air, air in the workplace, exhaust gas, heat-generating gas or human or animal breath, and the gas sample containing the component to be continuously flowed to the component to be measured. On the other hand, the absorbing liquid having a large dissolving power or reacting selectively is formed into fine droplets, and is sprayed onto a thread-like or granular resin or inorganic surface whose inner wall of the thin tube or the surface attached or filled in the thin tube is not smooth. The gas sampling apparatus according to claim 1, wherein the component to be measured is continuously concentrated and collected in the absorbing solution by moving the gas sample together with the gas sample. A pump for sucking / discharging the gas sample, a gas flow meter for adjusting the gas sample suction / discharge amount, a nebulizer for sucking and finely dropping the absorbing liquid by the flow of the gas sample, and the gas sample; A denuder in which the finely divided absorption liquid flows while continuously contacting, and a gas-liquid separation for inertial separation of the absorption liquid in which the target component is collected and the gas sample in which the target component is collected and removed. The gas sampling device according to claim 1, further comprising a cylinder. The nebulizer is a cross-flow nebulizer or a coaxial nebulizer in which the gas sample containing the component to be measured, which is supplied by the suction / discharge pump, sucks the absorption liquid and jets the absorption liquid into fine droplets, or is atomized by an ultrasonic oscillator. An ultrasonic nebulizer having an ultrasonic oscillator in which the dropletized absorbing liquid is sprayed by the flow of the gas sample containing the component to be measured by the suction / discharge pump, and a constant flow rate only by suction of the nebulizer. The gas sampling apparatus according to claim 3, further comprising a liquid feed pump for supplying the absorbing liquid to the nebulizer at a constant flow rate when the pressure is not obtained. The denuder is a tube made of quartz, borosilicate glass or fluororesin, and the shape of the denuder is a straight tube having an inner diameter of 1 to 20 mm and a length of 10 to 2000 mm, or a loop or a coil. The gas sampling device according to claim 3. A filament or granular filler is inserted into or attached to the inner surface of the denuder tube, and the fine absorption droplets ejected from the nebulizer on the inner surface of the denuder tube and the surface of the filler flow through a suction / discharge pump. Wherein the thread-like or granular member filled inside the denuder tube is quartz, borosilicate glass, an inorganic silicate such as silica (SiO2), The gas sampling device according to any one of claims 3 to 5, wherein the gas sampling device is any one of a metal, an alloy, a ceramic, a fluororesin, carbon, and a synthetic polymer, or a composite material of two or more types. The gas according to any one of claims 3 to 6, wherein the inner wall of the denuder tube has a surface roughened by one of hydrofluoric acid, sulfuric acid, nitric acid, an alkaline solution, and an organic solvent, or two or more solutions. Sampling equipment. The nebulizer and the inlet of the denuder tube are connected so that the fine absorbing droplets ejected from the nebulizer are directly sprayed onto the inner wall surface of the denuder tube and the surface of the denuder tube filler without agglomeration. The gas sampling device according to any one of 3 to 7. The gas-liquid separation tube has a cylindrical shape, a lower half portion having a connection port for a denuder tube outlet, an upper end connected to a tube for exhausting the gas sample after absorbing the target component, and an L-shaped connector at the lower end. 4. A connector for connecting a tube for collecting the absorption liquid after collecting the target component, wherein the gas sample and the absorption liquid having passed through the denuder tube in the cylinder are inertially separated. 5. 9. The gas sampling device according to any one of 8. Between the suction / discharge pump and the gas tube connecting the nebulizer, there is an inlet with an open / close cock and an outlet with an open / close cock on the opposite side of the inlet of the container with a constant capacity, and the volume changes depending on the amount of collection. It has a tube joint for connecting a gas collecting container, and the gas collecting container collects human expiration after a certain amount of alcohol loading, and the human expiration collected by the gas collecting container. 10. The method according to claim 3, wherein the medium component is sent to the nebulizer by the flow of air or other carrier gas by the suction / discharge pump, and the expiratory component is concentrated and collected in the absorbent. A gas sampling device according to claim 1. An activated carbon-containing air filter for collecting the volatile component of the absorbing liquid in the exhaust tube connected to the upper end of the gas-liquid separation tube, or another denuder tube and another gas-liquid separation tube for collecting the volatile component The gas sampling apparatus according to claim 9, further comprising another air pump for the volatile component recovery denuder and another pump for sending the absorbing liquid. A gas analyzer, comprising: the gas collection device according to any one of claims 4 to 11; a detection device for detecting a target component; and a data processing function of the detected component. The detection device is a portable flow injection analyzer (FIA), gas chromatography (GC), gas chromatograph / mass spectrometer (GC / MS), ion chromatography (IC), high performance liquid chromatography (HPLC), visible light The gas analyzer according to claim 12, which is any one of an ultraviolet absorption photometer (UV / VIS), a fluorometer, an infrared spectrophotometer (IR), a pH meter, an electric conductivity meter, and an automatic titrator. The concentration and collection of the measurement target component by the gas sampling device and the detection process of the measurement target component by the detection device, the data processing function and control function for continuous automatic operation for about 30 hours, and the 14. The gas collecting device according to claim 12, wherein the gas collecting device, the detecting device, the data processing function, and the control function are housed in a single portable table, and can be transported to an analysis target point of the measurement target component. Gas analyzer. Using the gas analyzer according to claim 14, the measurement target component is concentrated and collected from the measurement target gas to the absorption liquid by the gas sampling device at the analysis target point, and the target component is concentrated and collected. A gas analysis method comprising an analysis step of continuously measuring the concentration of the measurement target component in the absorption liquid by the detection device. A gas analysis method for measuring acetaldehyde concentration in human breath after a certain amount of alcohol loading by using the gas analyzer according to claim 14, and performing a simple screening test for a high risk group of head and neck cancer and esophageal cancer. .

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