JPS60170743A - Measuring instrument for gas concentration - Google Patents

Abstract

PURPOSE:To measure the concn. of hydrogen sulfide or gaseous chlorine in air easily with high precision by making a decision from the discoloring level and air absorption amount of gas sensitive filter paper which is discolored by passing the air through it by using a calibration curve chart. CONSTITUTION:Air is sucked by an air pump 9 and the air passed through the dust filter 2 in a filter case 1 is passed through the gas sensitive filter paper holder 11 which holds the gas sensitive filter paper 12. Then, the contacting state of the gas sensitive filter paper 12 with the gas is compared with samples of discoloring levels on a standard color chip to decide on the discoloring level, and a flow meter 7 is used to detect the flow rate of the sucked air. Then, the calibration curve chart is used to calculate the concn. of hydrogen sulfide or gaseous clorine from the discoloring level and flow rate.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a portable gas concentration measuring device that can accurately measure the concentration of hydrogen sulfide and chlorine gas in the air from low to high concentrations.

[Technical background of the invention and its problems]

Methods for measuring the concentration of hydrogen sulfide and chlorine gas include (1) solution conductivity method, (2) gas chromatography method, (3) filter paper coloring method, (4) detection tube method, and (5) spectrophotometry method. However, the solution conductivity method and gas chromatography method require large equipment and are difficult to make portable.

The filter paper coloring method involves reacting filter paper impregnated with a mixture of lead acetate, glycerin, and acetic acid with hydrogen sulfide, or
This method involves reacting F paper impregnated with 41-bis-dimegluaminothiopenzophenol solution with chlorine gas and measuring the degree of discoloration using a photoelectric photometer, but it is a reaction between a solid phase and a gas phase. Therefore, there are problems in that the reaction rate is low and the measurement accuracy is low.

Although the detector tube method is good for measuring high concentrations of 1 pI)m or higher, it is difficult to apply to low concentrations of less than 1 ppm.

In addition, although the spectrophotometry method allows measurement from low to high concentrations, it is difficult to transport the spectrophotometer itself, so a filter case 1 and a dust filter 2 as shown in Figure 1 are required.
, an absorption bottle 3, a gas (H, S or CtX) absorption liquid 4, a glass filter 5, a flow meter 7, a flow regulator 8 and an air pump '9). S or CI! R is absorbed into the gas absorption liquid 4 through the bubbles 6, and this is taken back and subjected to an absorption photometer.

Therefore, there are problems in that handling is troublesome and measurement takes time.

[Purpose of the invention]

An object of the present invention is to provide a portable gas concentration measuring device that can accurately measure the concentration of hydrogen sulfide or chlorine gas in the air.

[Summary of the Invention] The present invention provides a gas concentration measuring device for measuring the concentration of gas such as hydrogen sulfide or chlorine gas contained in the atmosphere, which includes an air pump that sucks the atmosphere, a filter that removes dust from the sucked atmosphere, A measuring device comprising a gas-sensitive F paper that changes color by reacting with gas in the atmosphere that has passed through the filter, a holder that holds the gas-sensitive filter paper, and a flow meter that measures the volume of the sucked atmosphere; It consists of a discoloration standard color chart that serves as a criterion for determining the discoloration level, and a calibration chart that determines the gas concentration based on the discoloration level determined above and the measured value of the flowmeter, and is used to determine the gas concentration such as hydrogen sulfide or chlorine gas contained in the atmosphere. This is a portable gas concentration meter that can easily and accurately measure the concentration of gas.

[Embodiments of the invention]

An embodiment of the present invention is shown in FIG.

FIG. 2 shows that a gas-sensitive filter paper holder 11 holding a gas-sensitive F paper 12 is used instead of the absorption bottle 3 in the conventional air sampling device described above, and the atmosphere that has passed through the dust filter 2 is directly passed through the gas-sensitive filter paper 11. ing.

Note that 13 is an O-ring to prevent air leakage, 14 is a screw for tightening the holder, and the other parts are the same as in FIG. 1.

Figure 3 shows the state in which the gas-sensitive filter paper has changed color due to contact with gas.
5, and the discoloration level can be determined by comparing it with the discoloration level sample 17 (a-X) on the standard color chart 16 in FIG. When the volume) is detected, the concentration of hydrogen sulfide or chlorine gas (pp.
b) I am able to put in the effort.

Figure 5 is a calibration curve that calculates the concentration of hydrogen sulfide from the discoloration level ('a-x) and the air flow rate Q). For example, when the discoloration level is C and the flow rate is 101! Then, the hydrogen sulfide concentration can be determined to be 4 ppb from the intersection point Cp.

The same applies to the case of chlorine gas shown in FIG.

〔Effect of the invention〕

As explained above, according to the present invention, gas-sensitive F paper is allowed to pass through the atmosphere to discolor, the level of discoloration is determined using a standard color chart, the amount of suctioned air is measured with a flow meter, and the amount of suctioned air and the level of discoloration are determined. Gases in the atmosphere (
A highly accurate and simple portable gas concentration measuring device for determining the concentration of hydrogen sulfide or chlorine gas is obtained.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an example of an air sampling device used in the conventional absorption photometry method, FIG. FIG. 4 is a diagram showing a photosensitive discoloration state, FIG. 4 is a diagram showing an example of a standard color chart for discoloration level, and FIGS. 5 and 6 are examples of calibration curve diagrams for hydrogen sulfide and chlorine gas, respectively. 1 Filter case 2 Dust filter 3 Absorption bottle 4 Gas absorption liquid 5 Glass filter 7 Dish needle 8 Flow rate regulator 9 Air pump 11 Gas-sensitive filter paper holder 12 Gas-sensitive P paper 16 Standard color chart (7317) Agent Patent attorney Nori Chika Yu [and 1 other person] Gu Hang Dai 3 Figure 1 Misfortune I7 Figure 5 o, / / tD to. /29n and El 51 (J?) Figure 6 All 5min, t'AJIi color (, (2n procedural amendment (voluntary) Showa 1st 59.12.- Mr. Commissioner of the Patent Office 1, Incident Indication of Japanese Patent Application No. 59-25987 2, Name of the invention Gas concentration measuring device 3, Relationship to the case of the person making the amendment Patent applicant (307) Toshiba Corporation 4, Agent Address: 105 Shibaura-chome, Minato-ku, Tokyo No. 1 No. 1 Toshiba Corporation Head Office Office 6. Details of the amendment (1) The entire text of the attached document will be corrected for the specification of the application. (2) Figure 7 will be added to the attached document of the drawings. Details Document 1. Name of the invention Gas concentration measuring instrument 2. Claims: Gas concentration υIll to be measured in the atmosphere
'd <, in S, an air pump that sucks the atmosphere;
In the atmosphere that is sucked 2. Measure the dust (i"filter fm that dazzles) and the volume of the sucked atmosphere. Using a measuring device equipped with a flowmeter, a standard discoloration chart that serves as a criterion for the discoloration level of the gas-sensitive 214 paper, and the discoloration level determined above and the measured value of the flowmeter, the gas zero quality is determined. Detailed Description of the Invention [Technical Field of the Invention] The present invention is capable of measuring the concentration of hydrogen sulfide, sulfur gas, and even sulfur dioxide gas in the air [from low concentration to high concentration]. This invention relates to a portable gas concentration measuring device that can measure concentrations with high accuracy. [Technical background of the invention and its problems] An alternative method for measuring the concentration of hydrogen sulfide, chlorine gas, and sulfur dioxide gas. (13 Bath liquid 74 volumetric method (2) Cass chromatography method (3) d″j paper layer color method (4) 111 quantity method (5) Infrared gas analysis method (6) Dimensional photometric detection method Ml et al. method (8) Detection method (9) Spectrophotometry method, solution conductivity method, gas chromatography method, superimposition method, infrared gas analysis method, and light absorption method etc., the equipment becomes large and it is difficult to carry out strict precautions. 1. Paper coloring method uses a mixture of vinegar, lead, glycerin, and acetic acid.
The impregnated #4 paper was completely reacted with hydrogen fluoride, and 1i
4-4'-bis-dimethylaminothiobenzobenzophenol solution R is soaked in *i4m and chlorine gas are reacted, and the degree of discoloration is measured using a light abrasive countermeter, but the reaction between the same phase and the gas phase is Therefore, there is a problem that the reaction rate is low and the measurement accuracy is low. The detector tube method is small and lightweight, making it convenient to carry.
Although it is suitable for measuring the above 16 concentrations, the measurement accuracy is slightly lower than the method (and is not suitable for measuring low concentrations below ippm. In addition, the spectrophotometric method can measure from low to high concentrations.
However, it is difficult to transport the light-absorbing needle itself, so we decided to prepare a filter case 1, dust filter 2, absorption bottle 3, gas (H2S or C12) absorption liquid 4, as shown in Figure 1. Glass filter 5, υiunt st 7
, an air sampling device consisting of a flow rate regulator 8 and an air pump 9.
The gas was absorbed into the gas absorbing chamber 4 through 6 A bubbles, and then taken back to the spectrophotometer. Therefore, there are problems in that handling is troublesome and measurement takes time. [Purpose of the invention] [Summary of the Invention] The invention provides a gas concentration measuring device for measuring the concentration of gases contained in the atmosphere, including an air pump that sucks the atmosphere, a filter that removes dust from the air that is sucked, and an air filter that completely passes through the filter. Gas sensitive 1 paper, gas sensitive f#, which changes color by reacting with the gas inside. A measuring device equipped with a flow meter to measure the volume of the sucked atmospheric air, a standard color chart for discoloration which is a criterion for determining the level of discoloration of the above-mentioned gas-sensitive paper, and a 6d judgment G above.
It consists of a calibration curve that completely determines the gas level from the discoloration level and the measured value of the flow meter, and the concentration of hydrogen sulfide or chlorine gas contained in the atmosphere can be measured easily and with high accuracy. This is a portable gas concentration measuring device. [Embodiment of the Invention] An embodiment of the present invention is shown in FIG. FIG. 2 shows that a gas-sensitive paper holder 11 holding a gas-sensitive paper 12 is used instead of the suction bottle 3 in the conventional air sampling device described above, and a large air sample that has passed through a dust filter 2 is used.
A is directly passed through gas-sensitive d4 paper 11. 13 is an O-ring to prevent air leakage, 14 is a screw for tightening the holder, and the other parts are the same as in FIG. 1. Here, as the gas-sensitive filter paper 12, the gas to be measured is 1J.
In the case of IIC hydrogen oxide, a mixture of silver nitric acid, nitric acid, glycerin and ethanol is used.
28 sensitive f'Mf, using gold. Figure 3 shows the state 15 (i-) in which the gas-sensitive paper 12 has changed color due to contact with gas. Figure IA4 shows a state in which the paper 12 has changed color due to reaction with hydrogen sulfide of a known concentration, and is plated with sodium thiosulfate. , 0 indicating the created standard color chart 16, sample 17 (axx) of the discoloration level on this standard color chart 16, and the gas feeling 1
The level of discoloration can be determined by comparing it with the portion of the paper 12 that has discolored due to contact with the gas (Fig. 3, 15). Accordingly, the flow rate (volume) of the air sucked using the flowmeter 7
When t-detection is performed, the concentration (ppb) of hydrogen sulfide gas can be determined according to the calibration curve shown in FIG. That is, Fig. 5 is a calibration diagram that determines the hydrogen sulfide concentration f (i-) from the discoloration level (a-X) and the air flow rate (1). For example, if the discoloration level is C and the flow rate is IOJ, From the cross point Op, the hydrogen sulfide concentration is estimated to be 4 ppb. According to this method, the sulfide water system F4i1 with a low mold level to a high concentration
It is easy to display and can be easily analyzed on the spot. When the foot gas to be measured is cellulose gas, the gas-sensitive corner portion 12 is made of sensitive paper impregnated with a gold mixed solution of orthotolidine, hydrochloric acid, glycerin, and ethanol. Then, as in the case of hydrogen sulfide, the level of discoloration is determined by comparing the degree of discoloration caused by the reaction of chlorine with sulfur to the standard color chart 16 as shown in Figure 4, which was prepared by subjecting the reaction discoloration to a known concentration. do. Further, the discoloration level determined by this standard color chart 16 and the flow rate are inserted into the calibration curve shown in FIG. 6 to obtain the base yarn ds ablation degree τ measurement. Furthermore, if the gas to be measured is sub-C acid gas, the gas feeling ↓
As the Snake and Tsuki J 12, use a mixture (6 liquid R) of a mixture (6 liquids R) of a mixture of Hosei J, potassium iodide, potassium iodide, glycerin, and ethanol.Then, this sensitive paper 12 is As shown in Fig. 3, the extent of discoloration due to reaction with sulfur dioxide gas, τ, is 7% compared with the standard color system 16 shown in Fig. 4, which was created by reacting with gas and discoloring, τ. The discoloration level L44J is further determined by this standard color system 16.
, and applied it to the calibration curve shown in Figure 7.
Measure the height of Suiso. [Effects of the Invention] As explained above, according to the present invention, J'L is
The level of discoloration is determined using a standard color system, and the amount of gas in the atmosphere is measured using a suction nitrogen + C flow meter, and a calibration chart is used based on the amount of suction air and the discoloration level. A highly accurate and simple portable gas concentration measuring device for determining whether or not a person is fighting back is obtained. 4. Drawing 1] Brief explanation: Figure 1 is a schematic diagram showing an example of an air zangling device used in the conventional absorption photometry method, and Figure 2 is a schematic diagram of an air zangling device according to the present invention. Figure 143 is a diagram showing the state of photosensitive discoloration of one gas-sensitive paper in Figure 2, Figure 4 is a diagram showing an example of a standard color chart for the discoloration level, Figures 5 and 6. and FIG. 7 is an example of a calibration curve diagram for -f:r used in the present invention. l Filter case 2 Dust filler 3 Absorption bottle 4 Gas absorption liquid 5 Glass filter 7 Flow rate αF s tAf, amount adjuster 9 Air pump 11 Gas sensitive TJ paper holder 16 Standard color chart

Claims (1)

[Claims] In a gas concentration measuring device that measures the concentration of gases such as hydrogen sulfide or chlorine gas contained in the atmosphere, there is an air pump that sucks the atmosphere, a filter that removes dust from the air that is sucked in, and a gas that passes through the filter. A measuring device equipped with a gas-sensitive filter paper that changes color upon reaction, a holder that holds the gas-sensitive filter paper, and a flowmeter that measures the volume of the sucked atmosphere, and a color change standard that serves as a criterion for determining the level of discoloration of the two gas-sensitive papers. A gas concentration measuring device comprising a color prefecture and a cross wind diagram for determining gas concentration from the determined discoloration level and the measured value of the flow meter.