JPS63120239A - Automatic gas analyzer - Google Patents

Abstract

PURPOSE:To sample and analyze a large number of specimen gases by one operator, by successively supplying the specimen gases collected by a large number of collection means to the transfer pipe communicating with an analyser through the corresponding automatic on-off valves. CONSTITUTION:Predetermined specimen gases are sampled in a large number of specimen sampling containers 11a-11i forming a collection means 11 from sampling points and said containers 11a-11i are respectively connected and mounted to the protruded parts of a piping system equipped with automatic on-off solenoid valves 12a-12i. These valves 12a-12i are successively opened through a control circuit 9 and the respective specimens of the containers 11a-11i are sent to the transfer pipe 1 connected to an analyser through a transfer means 14 and the valves 12a-12i after the completion of analysis are similarly closed automatically. By this constitution, the sampling and analysis of a large number of specimens for measuring the concns. of CO2 and O2 contained in specimens such as the exhaust gases of an engine can be performed by one operator and efficient analysis is performed under labor saving.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an automatic gas analyzer suitable for measuring CO2 and O2a degrees in gas discharged from combustion equipment such as boilers and diesel engines.

[Conventional technology and its problems] CO2 and 0zil contained in combustion gas! Measurement of nitrogen oxides is an essential measurement item for use in calculating the efficiency of boilers, diesel engines, etc. and converting nitrogen oxide concentrations. As a gas analysis method for this purpose, an analyzer using a stepping motor (hereinafter referred to as the stepping method) is used.
The stepping method has only one sample gas inlet, so there is no problem if the sample gas is sampled from one point.
It is unsuitable for multiple point analysis aimed at the distribution in the flue of combustion equipment. Therefore, when analyzing multiple points using the stepping method, it is necessary to perform an operation to introduce the next sample after the analysis of one point is completed, and the complicated operation becomes more efficient and labor-saving. There was a problem that was a hindrance.

The present invention has been made in view of these points, and provides an automatic gas analyzer that can collect and analyze a large number of sample gases with only one operator, and achieves efficiency and labor savings in analysis work. This is what we provide.

[Means for Solving the Problems] The present invention provides a collection means for collecting sample gas, a transfer means for transporting the sample gas of the collection means to an analysis chamber, and the collection means. comprising an automatic on-off valve for selecting a predetermined sample gas from among the sample gases, and piping for sequentially transferring the sample gases of the plurality of collection means to the analyzer via the automatic on-off valve. This is an automatic gas analyzer featuring:

[Operation 1] According to the automatic gas analyzer Δ according to the present invention, it has a collection means that can collect sample gas at multiple points at once, and
At the same time, a connection protrusion is provided on one end of the collection means so that the collection means can be connected, a transfer means is provided on the other end, and piping with an automatic on-off valve is installed between the protrusion and the transfer means. Because of this arrangement, it is possible to continuously measure the concentrations of CO2 and 02 contained in the sample gas.

[Examples] Examples of the present invention will be described below with reference to the drawings.

The figure is an explanatory diagram showing a schematic configuration of an embodiment of the present invention. Reference numeral 11 in the figure indicates a sample gas collection means.

The collection means 11 is composed of 11 flexible sample gas collection containers a to i that do not leak. It is sealed with a fixture. Each collection means 11a
~Ili are connected to each automatic opening/closing valve 12 consisting of electromagnetic valves 12a to 12i, etc. The automatic on-off valve 12 opens the valve portion when energized, and closes the valve portion when the energization is stopped. The collection means 11 is connected to a transfer means 14, such as a diaphragm pump, through an automatic on-off valve 12. The transfer means 14 is adapted to transfer the sample gas from a predetermined collection means 11 to an analyzer main body, which will be described later. The automatic opening/closing section 12 and the transfer means 14 are linked by a control circuit 9. A printer 10 is connected to the control circuit 9. The automatic opening/closing section 12 and the transfer means 14 are housed in a box 13. The transfer means 14 connects the analyzer main body 20 to the analyzer body 20 via a pipe 1 made of a material with low gas adsorption, such as detrafluoroethylene.
It is connected to the. That is, the pipe 1 exiting the transfer means 14 is connected to the three-way pipe 1a. The sample gas distributed by the three-way pipe 1a is passed through two electromagnetic valves 1b whose valve parts are made of a corrosion-resistant material.

1 (II).The solenoid valves 1b and 10 are
The valve part is closed when energized, and closed when the energization is stopped. Note that solenoid valves 1e and 1j will be described later.

A similar operation is performed for If,1. The sample gas that has exited the electromagnetic valves 1b and 1 is supplied to glass traps @lc and Ih that store water in order to keep the water concentration contained in the sample gas constant.

The sample gas exiting the trap tubes 1c and 1h is transferred to the three-way tubes 1d and 1h.
One of the sample gases that exited 1j is transferred to the suction and discharge sections 2 and 5 in total n
It is designed to be guided to tubes 2a and 5a. Measuring tube 2a
, 5a is in the shape of a syringe barrel, its outer barrel and inner chamber are treated with a highly airtight seal, and has an internal volume of 50 to 100 m. A detection unit 3 is installed in the inner cylinder of the total of 1 tubes 2a and 5a.
．． 6 stepping motor 3a.

Feeds tfi 12b and 5b are connected with each other, each of which has a spiral groove formed therein and moves with the rotation of tfi 6a. Feeding mechanism 2b.

The stepping motors 5b are driven by applying predetermined pulses to the stepping motors 3a and 6a. The stepping motors 3a and 6a are designed to electrically count applied pulses. Therefore, stepping motor 3
indirectly from the number of rotations of a and 6a to the metering tube 2a.

The internal volume of 5a can be detected. The feeding mechanisms 2b, 5b are provided with microswitches 2c for limiting their driving ranges and the top dead centers of the metering tubes 2a, 5a.

2d, 2e, 5c, 5d, 5e are attached to the tail.

The top dead center is the start position and the stepping motor 3a, which is responsible for the operation of the suction and discharge section 2.5 and the operation of the absorption section 4.7.
, 6a is used as the zero rotation position. The microswitches 2e, 2d, 2e, 5e, 5d, and 5e are ordinary ON-OFF switches with a small bar attached, and are disposed at the upper limit or lower limit position of the drive mechanism 2b, 5b. The sample gas from the metering tubes 2a, 5a is discharged from the N solenoid valves H, 1k.

A fixed amount of sample gas metered by the meter tubes 2a, 5a is guided to the absorption vessels 4d, 7d of the absorption sections 4, 7 by the 'R magnetic valves 1e, Ij. Absorption 1 vessel 4d.

7d is composed of an inner tube and an outer tube made of a transparent material. At the bottom of the inner cylinder, recesses for placing the rotors 4f, 7f are formed to prevent eccentricity of the rotors 41, 7f. A cylinder having an inner diameter larger than the outer diameter of the four parts at the bottom of the inner cylinder is attached to the inside of the upper part of the outer cylinder.

The inner cylinder and the outer cylinder maintain airtightness and can be attached to and removed from each other.

The absorption containers 4d and 7d are installed on the rotators 4 (J and 7Q).The rotators 4g and 7g have small motors with magnets attached inside them, and are driven by the small motors that drive the rotors 41 and 7f. It is designed to rotate.Absorption container 4
d contains a potassium hydroxide aqueous solution 4e for absorbing CO2 gas, and the absorption container 7d contains CO2.
It contains a mixed aqueous solution 7e of potassium hydroxide and pyrogallol for absorbing gas and 02. absorption container 4d,
At the top of the outer cylinder 7d is an absorption liquid 4e.

Platinum wires 4c and 7c for detecting the liquid level 7e are embedded. The platinum wires 4c and 7c are used as reference electrodes for the absorbing liquid level, the platinum wires 4a and 7a are used for detecting the absorbing liquid level in the first stage, and the platinum wires 4b and 7b are used for detecting the absorbing liquid level in the final stage. Arranged for surface detection. In addition, analysis system 1
A temperature regulator 8 is provided within the main body 20 . The humidity controller 8 is a second device that maintains the inside of the piping 1 at a predetermined temperature, and is configured to maintain a uniform temperature using a circulation fan. The main ffi control range is the introduction of the sample gas, the metering of the sample gas, the opening and closing of the solenoid valve, etc., and the amount of sample gas in the measuring tubes 2a and 5a is controlled by the stepping mode. After being counted as pulse numbers from 3a and 6a, the pulses are digitally scanned and printed and recorded on the arithmetic ink printer 10.

The automatic gas analysis device configured as described above analyzes a sample gas according to the following procedure.

(1) Sample gas is sampled from a predetermined sample gas sampling point using a plurality of collection means 11, and the sample gas is connected and attached to a convex portion at one end of the piping system.

(2) 1! In a predetermined order of the I collection means 11 (lia, 1
1b, -------11i) When conducting an analysis, the automatic opening/closing valve 12a is closed during the interval C, and at the same time, the sample gas from the collection means 11a is sent into the analyzer main body 20 by the transfer means 14.

(3)? [Magnetic valve B, Ik @ open, : l, tek Ln4mo 93a.

6a and move the feed mechanisms 2b, 5b to the positions of the microswitches 2c, 5e, then the solenoid valves 1f, 1
Close k.

+4) Open the solenoid valves 1e and lj and rotate the stepping motors 3a and 6a again to remove the absorption liquid 4e in the absorption containers 4d and 7d.

The liquid level 1e is rapidly raised to the platinum wires 4a, 7a, and then gradually raised to the platinum wires 4b, 7b. after that,
'Close the R magnetic valves 1e and lj. N solenoid valve 1B, 11k again
is opened, the stepping motors 3a and 6a are rotated, the meters 12a and 5a are moved to the positions of the microswitches 2c and 5c, and the solenoid valves H and 1k are closed.

With the above operations, measurement preparation is completed.

(5) When the sample gas to be analyzed is supplied from the pipe 1, the sample gas is divided into two by the three-way pipe 1a.

(Open the 61M magnetic valves 1b and 1, and open the stepping motor 3.
a.

6a, and after closing the measuring tubes 1b and 1(l), the solenoid valve 1f is closed.

1k and discharge the sample gas from the measuring tubes 2a and 5a.

(7) Repeat the operation in item 4 above, measuring tube 2a,
5a is replaced with the sample gas.

(8) Open the N solenoid valves 1b and 1g, drive the stepping motors 2a and 6a to pull up the metering tubes 2a and 5a,
After sucking and collecting the sample gas, the solenoid valves 1b and 1g are closed.

9t11! l valves 1b, 1g,! : In order to make atmospheric pressure between the flow paths of electric valves 1 and 1b, 74 solenoid valves 1f and Ik are opened for a certain period of time and then closed again.

(10) Open the solenoid valves 1e and lj and simultaneously drive the stepping motors 3a and 6a to raise the liquid level of the absorbent liquids 4e and 7e in the absorption containers 4d and 7d rapidly up to the platinum wires 4a and 7a, and then gradually. After pulling up the platinum wires 4b and 7b, the solenoid valves 1e and 1j are closed. The rotational speed of the stepping motors 3a, 6a at this time is stored in the control circuit 9 as a reference rotational speed.

(11) Open the solenoid valves 1e and Ij, and open the 5 pipes 2a and 5.
After driving the stepping motors 3a and 6a to send the sample gas in the sample gas into the absorption containers 4d and 7d, the sample gas is returned to 1fE41.
Close valves 1e and 1j.

(12) When the sample gas is introduced into the absorption containers 4d and 7d, the rotors 41 and 7 in the absorption containers 4d and 7d simultaneously
f is rotated by rotator 4 (J, 7Q), and the sample gas and absorption liquid 4e are rotated.

7e is stirred and brought into contact with Co2 and CO2 in the sample gas.
and 02 are absorbed respectively.

(13) After a certain period of time, open the solenoid valves 1e and 1j, drive the stepping motors 3a and 6a, and open the absorption containers 4d and 1j.
The unabsorbed gas of 7d is absorbed by liquids 4e and 7e, whose liquid level is the platinum wire 4.
b.

7bk: Transfer to the control tubes 2a and 5a until the position reached.

<14> Stepping motor 3a of (11),
The number of revolutions 6a is stored in the υl111 circuit 9 as the first number of revolutions.

(15) In the control circuit 9, the stepping motor 3a
.

Using the memory value of the reference rotation speed in 6a, measure by the following formula I
The results are calculated and the concentration of Go2 and 02 in the sample gas (%
) is printed on the printer 10 after printing C02 (%) - Measured rotation speed / Reference rotation speed x 100 GO2 + 02 (%) 1 Measured rotation speed / 'Reference rotation speed x 100 02 - (COZ +02 ) (%) - (CG2 )(%
) (16) After the first measurement, ill! The Jl1 circuit 9 returns to the state in section 3 and is reset to prepare for the next measurement.

(17) Open the automatic on-off valve 12b again and open the collection means 1.
11) The sample gas is sent to the analyzer main body 20.

Thereafter, the same operation is repeated for 110 +11 collecting means.

In order to confirm the effectiveness of this device that automatically analyzes sample gas in this way, we selected combustion exhaust gas as the sample gas and examined the measurement results.
The values are shown in the column. Also, o, 1. Regarding l=M, the value was shown in the same table as ×2 1.

For comparison, similar measurement results using an Orguts type 9-pass analyzer were as shown in the same table, with CO2 indicated by Y1 and O-2 indicated by Y2. As is clear from these results, C(i)2,0,02 all agree within the range of 0,1 to 0,2. Furthermore, it was confirmed from the value of the correlation coefficient r, which indicates the good luck between the two, that the apparatus of the example has a very similar relationship to the Orzala 1-type gas analyzer.

Table Measurement results using the device of the present invention and the Orgut-type 9-pass analyzer 2 4.2 4,3 2 20,1
20.13 0.5 0.5 3
4.3 4.54 4.84゜9 4
20.0 20.15 7.5 7,6
5 19.3 19,46 14.9
15.1 6 18.9 18.97
12.6 12.7 7 19.4
19,48 9.9 10.0 8
19.6 19.69 7.4 7. G
9 2,4 2,510 6.0
G, 0 10 0,9 1.011
2.6 2,6 11 1,3 1,
312 3.9 3,9 12 5.
1. 5.113 6.2 6.4
13 11,4 11,414 5.0 5.
0 Number of data N-15N-13 Correlation coefficient r -0,9998r -0,9999 Identical line Y -a +b X D,, eyes + 24 (2,
'I+)χ, FIIIV,)a = 7.7862-0
．． 3 a -0,0787b -1,0114b
-0,9980 absorption liquid 4e Calcium hydroxide aqueous solution absorption liquid 7e *Aqueous solution of calcium oxide + pyrogallol It is possible to collect and analyze sample gases of 1,000 yen, achieving efficiency and labor savings in analysis work.

[Brief explanation of the drawing]

The figure is an explanatory diagram showing a schematic structure of an embodiment of the present invention. 1... Piping, 2, 5... Suction and discharge section, 3, 6...
Detection section, 4.7... Absorption section, 8... Temperature regulator,
9... Control circuit, 10... Printer after printing,) 1
. . . Collection means, 12. Automatic opening/closing valve, 13. Box, 14. Transfer means, 20. Analyzer body.

Claims (1)

[Claims] a collection means for collecting sample gas; a transfer means for transporting the sample gas of the collection means to the analyzer; and an automatic system for selecting a predetermined sample gas from among the collection means. An automatic gas analyzer comprising: an on-off valve; and piping for sequentially transferring the sample gas from a plurality of the collection means to the analyzer via the automatic on-off valve.