JPS60222767A - Monitor device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to improvements in monitoring devices, and in particular to improvements in monitoring devices for organic vapors present in an atmosphere.

BACKGROUND OF THE INVENTION It is known in the art to test the atmosphere of a work area to detect contaminants. One basic type of device is active and passive, where active devices use a pump to draw atmosphere into the device and release contaminants for analysis after a known period of time, for example for infrared analysis. Continuously monitor contaminants by adsorbing/desorbing them onto materials that can Passive devices operate without the use of pumps 7 and function normally by dissipating the atmosphere and collecting contaminants on appropriate materials. Although these two M-type commercially available test devices have been successful, they have not been found to be able to accurately test atmospheres containing very small amounts of organic vapors with values of /'0' ppm. For example, sirapine 9 (-
Niosh charcoal absorption tubes with Sonal sample pumps are widely used in the United States, United Kingdom, and other countries as an accurate method for detecting benzene, toluene, xylene, etc. in workplaces.

1. The Kaji and Niosh devices have not been confirmed to be used at concentrations below 0.7 ppln. By replacing the charcoal tube with a vapor adsorption tube using a polymeric adsorption material, Tenax OC, approximately ? Although the lower measurement limits are improved to X/0' ppm, the requirement for constant supervision of each test point precludes simultaneous monitoring of large areas, such as coke factory environments17.

Passive monitoring or radiometry is based on the emission of individual organic vapors and the physical configuration of the monitor.

Several passive monitors are commercially available, are relatively inexpensive, and offer many possibilities of use without requiring much effort. Many of these use charcoal-impregnated materials or charcoal particles to accurately measure very low values of airborne contaminants, while 1. adsorbing high values of contaminants. It is impossible for divine reasons including [2]. There are also commercially available passive monitoring devices that use polymeric sorbents, allowing improved performance over charcoal types, but do not have accuracy in the IO'ppm range.

The invention comprises a charge of adsorbent, and a first sample chamber;
an adsorbent holding body having a second desorption chamber connected and arranged so that the adsorbent charge can be placed in the first sample chamber, and the adsorbent charge is exposed to the atmosphere to prevent organic contamination. Organic contaminants can be retained for analysis as the adsorbent can be processed to adsorb organic contaminants by adsorbing substances and converting without manipulation to a second desorption chamber at the end of the scheduled test period. The first sample chamber has a larger cross section than the second desorption chamber (2), and is a novel passive device capable of measuring the concentration of organic vapor in the atmosphere with an accuracy of /0' ppm. The purpose of the present invention is to provide a reliable monitoring device.

Preferred adsorbents are polymeric adsorbents that are capable of absorbing organic vapors at reasonable concentrations in air and that perform all adsorption without the need for treatment with liquid solvents. The adsorbent can be used as an adsorbent that can substantially desorb vapors. Preferably, desorption is performed by heating using a flow of purge gas to transport the adsorbed substances outside the holding body for analysis. The method of analysis is non-critical and provides sufficient precision at the concentration values encountered; chromatographic methods are preferred.

Preferably, the adsorbent holding body 1-1 consists of one cylindrical body, one having a relatively large diameter to length ratio. −
C to form the first chamber and the other one having a relatively small diameter to length ratio to form the λ-th chamber. Preferably, by a simple inversion, the adsorbent is free from gravity. A simple and effective structure is provided by a simple coaxial connection of the cylinders.The adsorbent holding body provides access to the atmosphere to be tested and allows the adsorbent to flow from one chamber to another. loss of adsorbent must be prevented, and likewise no loss of adsorbent when desorption takes place. Preferably, limited radiation of the atmosphere to the adsorbent is carried out using a fine mesh. The adsorbent holding body may be provided with a connecting means by which the gas supply pipe () is maintained in place by the adsorbent holding body. [The desorbed contaminants can be connected to the gas carrier and flowed to the analyzer.]

The invention will now be described with reference to the accompanying drawings.

Referring to the embodiment drawings, the monitoring device includes a first sample chamber and a second sample chamber.
A holding body/ having a detachment chamber 3 is provided. In FIG. 1, the end of the λ-th desorption chamber 3 is sealed with a tap-shaped fitting η, and the 2sO to SOO micron tenax GC
'''A charge S of 00.2 grams of polymer adsorbent is held by a metal mesh disc with holes 6 of 75θ microns. Another such 4137 is held by a nut 8 with a removable It is attached to the open end of the sample chamber to prevent particles from entering, and if necessary, a permeable membrane, preferably made of polytetrafluoroethylene, can be used instead of the membrane 7.
Can be used in addition to.

In the desorption condition as shown in FIG. 1, the holding body is inverted and the adsorbent charge flows to fill the desorption chamber 3. An oak with a gas connection 10 so that the tap-shaped fitting can be removed and the gas/contaminant mixture transferred to a gas chromatograph (not shown)? can be replaced with The nut has a gas inlet 12/
/ can be replaced with

In use, the monitoring device is placed in place as shown in FIG. The atmosphere contacts the relatively large surface area of adsorbent exposed at disk 6, and organic vapor contaminants are adsorbed. At the end of a preselected exposure time, e.g. time S, a closure nut (not shown) is used to seal the open end of the monitoring device, freeing the monitoring device for later analysis.
F or storage. For analysis, the configuration of Figure 1 is used, a narrow desorption chamber 3 with adsorbent is attached to a heating block, dry nitrogen is flushed and the adsorbed pollutants are analyzed by gas chromatography.

Initial tests have shown that approximately 13
It shows the impregnation of twice the amount of polluting organic vapors. In addition to very organically dilute accurate monitoring, the same monitoring device can be used for higher pollutant values in ppm with short exposure times, e.g. in minutes.

[Brief explanation of drawings]

1 is a sectional view of a monitoring device according to the invention prepared for testing an atmosphere, and FIG. 2 is a sectional view of the monitoring device of FIG. 1 prepared for adsorption of contaminants. In the figure, /: holding body, sample chamber, 3: desorption chamber, q: fixture, S: charge, 7: board, g, ta, //: nut, /θ:
Gas connections, / Konigas people! ]. Patent applicant's agent Dosho Soga Engraving of the drawing (no change in content) FIG, I FIG, 2 Procedural amendment (method) May 27, 1985 Commissioner of the Patent Office Shiga Palm print 1, indication of the case 1985 Patent Application No. 11144 of 20132, Title of Invention Monitoring Device 3, Relationship with the person making the amendment Patent applicant name: Coal Industries (Patents) Limited 4, agent: 100 Address: 2-chome Marunouchi, Chiyoda-ku, Tokyo No. 4, No. 1 Marunouchi Building, 4th floor, 5, Date of amendment order ゛・--１～・Puff, Contents of amendment (1) As per the engraving and attached sheet of the drawings originally attached to the application (
(No change in content)

Claims (1)

[Claims] l A charge of adsorbent and a first desorption chamber having a first sample chamber and connected to a first desorption chamber provided so that the charge of adsorbent can be placed in the first sample chamber. The sorbent charge is exposed to the atmosphere to adsorb organic contaminants, and at the end of the scheduled test period can be transferred to a second desorption chamber without any manipulations. can be treated to adsorb organic contaminants so that the organic contaminants are removed from the holding body for analysis, and the first sample chamber has a larger cross-sectional area than the desorption chamber of #J2. A monitoring device capable of measuring the concentration of organic vapor in an atmosphere with an accuracy of /0' ppm. (c) The monitoring device according to claim 1, wherein the adsorbent is a polymer adsorbent. 3 1st. A patent characterized in that the first chamber is cylindrical, the first chamber has a relatively large length-to-diameter ratio, and the second chamber has a relatively small length-to-diameter ratio. A monitoring device according to any one of claims 1 and 1. (h) Inversion from one position to another is sufficient to cause the adsorbent to flow by gravity from one chamber to another.
The monitoring device R8S described in Claim 1 is provided with a connecting means to which a gas supply pipe can be connected, and the gas adsorbing and transporting contaminants can flow out of the holding body for analysis.
The monitoring device according to any one of the following items.