GB2161605A - Apparatus for continuously measuring concentration of hydrogen or steam contained in gas - Google Patents
Apparatus for continuously measuring concentration of hydrogen or steam contained in gas Download PDFInfo
- Publication number
- GB2161605A GB2161605A GB08513589A GB8513589A GB2161605A GB 2161605 A GB2161605 A GB 2161605A GB 08513589 A GB08513589 A GB 08513589A GB 8513589 A GB8513589 A GB 8513589A GB 2161605 A GB2161605 A GB 2161605A
- Authority
- GB
- United Kingdom
- Prior art keywords
- measuring tube
- gas
- plug
- hydrogen
- electromotive force
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
- G01N27/403—Cells and electrode assemblies
- G01N27/406—Cells and probes with solid electrolytes
- G01N27/407—Cells and probes with solid electrolytes for investigating or analysing gases
- G01N27/4073—Composition or fabrication of the solid electrolyte
- G01N27/4074—Composition or fabrication of the solid electrolyte for detection of gases other than oxygen
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Health & Medical Sciences (AREA)
- Physics & Mathematics (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Molecular Biology (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Measuring Oxygen Concentration In Cells (AREA)
Abstract
Apparatus for continuously measuring the concentration of hydrogen or steam contained in a gas comprises a measuring tube (1) composed entirely of a solid electrolyte mainly comprising a mixture of strontium oxide and cerium oxide constituting a test- tube-like integral body, having an electro-conductive annular terminal (4) at its open end, an outwardly directed projection 3 around its middle portion and being filled with a standard gas containing hydrogen or steam at a prescribed concentration; an electro-conductive plug (7) securing the measuring tube (1) to a wall (2a) of a chamber containing a gas to be measured, with at least the tip portion of the measuring tube (1) projecting into the chamber. A porous inner electrode (5) covers substantially the entire inner surface of the measuring tube (1), with its end edge connected to the annular terminal (4). A porous outer electrode (6) covers substantially the entire outer surface of the measuring tube (1) so as to face the inner electrode (5), with its end edge connected to the plug (7) via gasket 11. An electromotive force detector (14), has one terminal connected to the inner electrode (5) through the annular terminal (4), and its other terminal connected to the outer electrode (6) through the plug (7). <IMAGE>
Description
SPECIFICATION
Apparatus for continuously measuring concentration of hydrogen or steam contained in gas
The present invention relates to an apparatus for continuously measuring the concentration of hydrogen or steam contained in a gas, employing a measuring tube of which at least the closed tip portion is composed of a solid electrolyte mainly comprising a mixture of strontium oxide and cerium oxide.
An apparatus for continuously measuring the concentration of hydrogen or steam contained in a gas, is disclosed in Japanese
Patent Provisional Publication No.
58-50,458 dated March 24, 1 983.
That apparatus comprises a measuring tube, whose closed tip is composed of a solid electrolyte comprising a mixture of strontium oxide and cerium oxide, said measuring tube being filled with a standard gas containing hydrogen or steam at a prescribed concentration, the outer surface of at least said tip of said measuring tube being in contact with a gas to be measured. A porous inner electrode is applied onto the inner surface of said measuring tube, and a porous outer electrode is applied onto the outer surface of said measuring tube so that said outer electrode faces said inner electrode with said solid electrolyte therebetween.An electromotive force detector for measuring an electromotive force produced between said inner and outer surfaces of said measuring tube, as a result of the difference in concentration of hydrogen or steam between said standard gas and a gas to be measured, is connected by respective first and second conductors to said inner and outer electrodes.
This prior art apparatus, and the apparatus according to the present invention, will be subsequently described with reference to the accompanying Drawings, in which:
Figure 1 illustrates schematically a longitudinal section through a conventional apparatus according to the prior art;
Figure 2 is a schematic longitudinal sectional view illustrating a first embodiment of the apparatus of the present invention; and
Figure 3 is a schematic longitudinal sectional view illustrating a second embodiment of the apparatus of the present invention.
As shown in Fig. 1, the prior art apparatus comprises a measuring tube 18, with a tubular main body 1 8a comprising a non-electroconductive material, such as alumina porcelain. The closed tip 1 8b of the measuring tube 1 8 is composed of a solid electrolyte having hydrogen-ion conductivity and comprising a mixture of strontium oxide (SrO) and cerium oxide (CeO2). The solid electrolyte may comprise a mixture of the strontium oxide and cerium oxide as essential constituents, with an oxide of at least one metal selected from yttrium (Y), scandium (Sc), ytterbium (Yb), neodymium (Nd), praseodymium (pr), magnesium (Mg) and zinc (Zn). The chemical formula of such a solid electrolyte is SrCe1 xMx03a wherein
M: at least one metal selected from Y, Sc,
Yb, Nd, Pr, Mg and Zn,
x: from 0 to 0.5, and a: from 0 to 0.5.
The tip 1 8b comprising the solid electrolyte is fitted to the lowermost end of the main body 1 8a by means of a vitreous adhesive whereby to close the lower end of the measuring tube 18. 19 is a junction between the main body 18a and the tip 18b.
A porous inner electrode 20 comprising, for example, platinum is applied to the inner surface of the tip 1 8b, and a porous outer electrode 21 comprising, for example, platinum is applied to the outer surface of the tip 1 8b, so that the outer electrode 21 faces the inner electrode 20 with the solid electrolyte therebetween.
The measuring tube 1 8 has a standard gas supply pipe 1 6 inserted concentrically into the measuring tube 1 8 through a hole provided in a cap 1 8c, for supplying a standard gas having a prescribed concentration of hydrogen or steam. The measuring tube 1 8 has at its upper portion a standard gas discharge port 1 7 for discharging the standard gas. In use, the standard gas having a prescribed hydrogen or steam concentration flows continuously through the measuring tube 18.
The measuring tube 1 8 may be placed within a chamber containing a gas to be measured, or may be secured, as shown in
Fig. 1, to a wall 2a of the chamber 2, so that at least the tip 1 8b of the measuring tube 1 8 projects into the chamber.
An electromotive force detector 14 is used for measuring the electromotive force produced between the inner and outer surfaces of the solid electrolyte as a result of the difference in concentration between hydrogen or steam in the standard gas and in the gas to be measured in the chamber 2. The inner electrode 20 is connected to one terminal of the electromotive force detector 1 4 by a first conductor 1 3 passing through the measuring tube 1 8. The outer electrode 21 is connected to the other terminal of the electromotive force detector 14 by a second conductor 13' passing through the chamber 2.
The electromotive force has a proportional relation to the difference in hydrogen or steam concentration in the standard gas and in a gas being measured. Thus, the concentration of hydrogen or steam contained in the gas in chamber 2 can be continuously determined.
Use of the apparatus of the prior art in volves securing the measuring tube 1 8 to a wall 2a of a chamber 2, so that at least the tip 1 8b of the measuring tube 18 projects into the chamber 2, which has the following drawbacks: (1) The measuring tube 1 8 expands and contracts with change in temperature of the gas in the chamber 2. As a result, the differences in thermal expansion between the main body 1 8a, e.g. comprising porcelain, and the tip 1 8b comprising solid electrolyte, cause cracks in the junction 1 9 between the main body 1 8a and the tip 1 8b. When such cracks occur, the gas to be measured in the chamber 2 penetrates into the measuring tube 18, thus preventing accurate measurement, and the tip 1 8b may even come off, making continued measurement impossible.
(2) The first conductor 13, connecting the inner electrode 20 to the electromotive force detector 14, vibrates under the effect of the standard gas flowing in the measuring tube 18, and the second conductor 13' connecting the outer electrode 21 to the electromotive force detector 14, also vibrates, under the effect of flow of the gas in the chamber 2. As a result, the respective connections between the first conductor 1 3 and the inner electrode 20, and between the second conductor 13' and the outer electrode 21 are easily susceptible to breaks. Such breaks of the connection between the conductors and the electrodes also make measurement impossible.
There is, therefore, a strong demand for the development of an apparatus for continuously measuring the concentration of hydrogen or steam contained in a gas, which exhibits excellent durability and permits stable and accurate measurement for a long period of time, irrespective of temperature changes in the gas to be measured, but such an apparatus has not as yet been proposed.
In accordance with the present invention, there is provided an apparatus for continuously measuring the concentration of hydrogen or steam in a gas, which comprises:
a measuring tube composed entirely of a solid electrolyte mainly comprising a mixture of strontium oxide and cerium oxide, constituting a test-tube-like integral body, having an outwardly-directed projection at its open end around its middle portion, and an electroconductive annular terminal;
an electro-conductive plug adapted to fit into a hole provided in a wall of a chamber for containing a gas to be measured, said plug having a recess engageable with said projection of said measuring tube, said projection being supported by said recess via an electroconductive gasket, whereby at least the tip portion of said measuring tube projects into said chamber;;
an inner electrode extending over substantially the entire inner surface of said measuring tube with its end edge connected to said annular terminal;
an outer electrode extending over substantially the entire outer surface of said measuring tube below said projection, the end edge of said outer electrode being connected to said gasket of said plug;
an electromotive force detector for measuring an electromotive force produced between said inner and outer electrodes as a result of the difference in concentration between hydrogen or steam contained in said standard gas and in a gas to be measured in said chamber;
a first conductor connecting said inner electrode to one terminal of said electromotive force detector through said annular terminal; and
a second conductor connecting said outer electrode to the second terminal of said electromotive force detector through said gasket and said plug.
The apparatus of the present invention is described with reference to the accompanying
Drawings.
Fig. 2 is a schematic longitudinal sectional view illustrating a first embodiment of the present invention. A measuring tube 1 is a test-tube-like integral body composed entirely of a hydrogen-ion conductive solid electrolyte comprising a mixture of strontium oxide (SrO) and cerium oxide (CeO2). The measuring tube 1 is prepared, for example, by press-forming a mixture of strontium oxide (SrO) powder and cerium oxide (CeO2) powder into a test-tubelike body, and then firing the formed body.
The solid electrolyte may, if desired, comprise a mixture of strontium oxide (SrO) and cerium oxide (CeO2) as essential constituents, with an oxide of at least one metal selected from yttrium (Y), scandium (Sc), ytterbium (Yb), neodymium (Nd), praseodymium (Pr), magnesium (Mg) and zinc (Zn).
The measuring tube 1 has on its middle portion a projection 3, formed integrally therewith, for example, from solid electrolyte, which projects outwardly. The measuring tube 1 has an electro-conductive annular terminal 4 at its open end. A plug 7, constituting fitting means for securing the measuring tube 1 to a wall 2a of a chamber 2 for containing a gas to be measured is fitted into a hole 2b provided in the chamber wall 2a, for example, by threading. The plug 7 has an axial recess 8 matching the projection 3 and a hole 9 adjacent the recess 8, into which the measuring tube 1 is inserted. The plug 7 has an electroconductive gasket 11 in electro-conductive contact with the wall of the recess 8. The projection 3 is supported by the recess 8, so that at least the tip portion of the measuring tube 1 projects into the chamber 2. A cap 10 is driven to the open end of the recess 8. The projection 3 is secured by the cap 10 in the recess 8 of the plug 7, and thus the measuring tube 1 is fixed to the plug 7. In Fig. 2, 12 is a sealing packing the gap between the projection 3 and the cap 10.
A porous inner electrode 5 comprising, for example, platinum covers substantially the entire inner electrode of the solid electrolyte of the measuring tube 1. The end edge of the inner electrode 5 is connected to the annular terminal 4. A porous outer electrode 6 comprising, for example, platinum covers substantially the entire surface of the portion of the measuring tube 1 below the projection 3 so that the outer electrode 6 faces the inner electrode 5 with the solid electrolyte therebetween. The end edge of the outer electrode 6 is connected to the gasket 11.
The inner electrode 5 and the outer electrode 6 can be applied to the respective surfaces of the measuring tube 1, for example, in the following conventional manner. Finely powdered platinum and resin are mixed together in the presence of a solvent.
The resultant mixture is applied to the inner and outer surfaces of the measuring tube 1, and then baked. As a result, the fine powder of the resin vaporizes, and thus porous inner and outer electrodes 5 and 6 comprising platinum reformed onto the respective surfaces of the measuring tube 1.
The measuring tube 1 is supplied or filled with a standard gas containing hydrogen or steam at a prescribed concentration as shown by the arrow in Fig. 2. 14 is an electromotive force detector for measuring an electromotive force produced between the inner and outer surfaces of the measuring tube 1, as a result of the difference in hydrogen or steam concentration between the standard gas in the measuring tube 1, and in a gas to be measured in the chamber 2. A first conductor 1 3 connects the inner electrode 5 to one terminal of the electromotive force detector 14 through the annular terminal 4 of the measuring tube 1, and a second conductor 13' connects the outer electrode 6 to the other terminal of the electromotive force detector 14 through the gasket 11 and the plug 7.
The measuring tube 1 is secured so that at least its tip portion projects into the chamber 2 by screwing the plug 7 through another gasket 1 5 into a hole 2b provided in a wall 2a of the chamber 2. Then, the measuring tube 1 is filled with the standard gas containing hydrogen or steam at a prescribed concentration.
Since the electromotive force measured by the electromotive force detector 1 4 has a proportional relation to the difference in hydrogen or steam concentration between the standard gas and the gas to be measured, it is thereby possible to determine the concentration of hydrogen or steam in the gas to be measured.
As described above, the measuring tube 1 in the present invention is a test-tube-like integral body composed entirely of the solid electrolyte and does not have a structure, as in the conventional measuring tube of the prior art, in which the tip composed of the solid electrolyte is fitted to the lowermost end of the main body of the measuring tube.
Therefore, even when the measuring tube 1 expands or contracts as a result of changes in temperature in the gas to be measured, cracks which are often observed in the conventional measuring tube of the prior art never occur in the tip portion of the measuring tube 1 of the present invention. In addition, the first conductor 1 3 connects the inner electrode 5 to one terminal of the electromotive force detector 14 through the annular terminal 4 of the measuring tube 1, and the second conductor 13' connects the outer electrode 6 to the other terminal of the electromotive force detector 14 through the gasket 11 and the plug 7. Therefore, both conductors 1 3 and 13' are connected to their respective electrodes 5 and 6 outside the effects of gas flow, and never break in the manner experienced in the conventional apparatus of the prior art.
Fig. 3 is a schematic longitudinal sectional view illustrating a second embodiment of the apparatus of the present invention. It is the same as that of the first embodiment described above, except that a standard gas supply pipe 1 6 is axially inserted into the measuring tube 1, and a standard gas discharge port 1 7 is provided in the annular terminal 4 fitted to the open end of the measuring tube 1. The standard gas supply pipe 16, comprising for example porcelain, is inserted axially into the measuring tube 1 through a cap 4a at the top of the annular terminal 4, and is secured to the cap 4a for example by an adhesive. In this second embodiment, the standard gas is supplied to the measuring tube through the standard gas supply pipe 1 6 and discharged through the standard gas discharge port 1 7. Thus, the standard gas can flow continuously through the measuring tube 1.
According to the present invention, as described above in detail, it is possible to achieve high durability of the apparatus and carry out stable and accurate measurement over a long period of time irrespective of changes in temperature of a gas to be measured, thus providing industrially useful effects.
Claims (3)
1. An apparatus for continuously measuring the concentration of hydrogen or steam in a gas, which comprises:
a measuring tube composed entirely of a solid electrolyte mainly comprising a mixture of strontium oxide and cerium oxide, constituting a test-tube-like integral body, having an outwardly-directed projection at its open end around its middle portion, and an electroconductive annular terminal;
an electro-conductive plug adapted to fit into a hole provided in a wall of a chamber for containing a gas to be measured, said plug having a recess engageable with said projection of said measuring tube, said projection being supported by said recess via an electroconductive gasket, whereby at least the tip portion of said measuring tube projects into said chamber;;
an inner electrode extending over substantially the entire inner surface of said measuring tube with its end edge connected to said annular terminal;
an outer electrode extending over substantially the entire outer surface of said measuring tube below said projection, the end edge of said outer electrode being connected to said gasket of said plug;
an electromotive force detector for measuring an electromotive force produced between said inner and outer electrodes as a result of the difference in concentration between hydrogen or steam contained in said standard gas, and in a gas to be measured in said chamber;
a first conductor connecting said inner electrode to one terminal of said electromotive force detector through said annular terminal; and
a second conductor connecting said outer electrode to the second terminal of said electromotive force detector through said gasket and said plug.
2. An apparatus as claimed in Claim 1 wherein said measuring tube has an axial standard gas supply pipe.
3. An apparatus as claimed in Claim 1 and substantially as hereinbefore described with reference to Fig. 2 or 3 of the accompanying Drawings.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59120464A JPS60263853A (en) | 1984-06-11 | 1984-06-11 | Detector for concentration of hydrogen or steam in gas |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB8513589D0 GB8513589D0 (en) | 1985-07-03 |
| GB2161605A true GB2161605A (en) | 1986-01-15 |
Family
ID=14786809
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08513589A Withdrawn GB2161605A (en) | 1984-06-11 | 1985-05-30 | Apparatus for continuously measuring concentration of hydrogen or steam contained in gas |
Country Status (4)
| Country | Link |
|---|---|
| JP (1) | JPS60263853A (en) |
| DE (1) | DE3520908A1 (en) |
| FR (1) | FR2565690B1 (en) |
| GB (1) | GB2161605A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4730635B2 (en) * | 2001-03-21 | 2011-07-20 | 独立行政法人産業技術総合研究所 | Hydrocarbon gas sensor and hydrocarbon gas concentration measuring method |
| RU2379672C1 (en) * | 2008-09-15 | 2010-01-20 | Федеральное государственное унитарное предприятие "Государственный научный центр Российской Федерации-Физико-энергетический институт имени А.И. Лейпунского" | Hydrogen detector in liquid and gas mediums |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1469698A (en) * | 1973-05-23 | 1977-04-06 | Bosch Gmbh Robert | Oxygen sensors for exhaust gases |
| GB1483763A (en) * | 1973-10-06 | 1977-08-24 | Bosch Gmbh Robert | Electrochemical sensors |
| GB2009412A (en) * | 1977-12-05 | 1979-06-13 | Bendix Autolite Corp | Electrochemical gas constituent sensor |
| GB2017926A (en) * | 1978-04-03 | 1979-10-10 | Gen Motors Corp | Heated solid electrolyte oxygen sensor |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1301917B (en) * | 1963-01-05 | 1969-08-28 | Foerderung Der Eisenhuettentec | Device for determining the oxygen activity of metals, metal oxides and slags in a liquid state |
| JPS49103695A (en) * | 1973-02-02 | 1974-10-01 | ||
| US3844920A (en) * | 1973-11-21 | 1974-10-29 | Gen Motors Corp | Air fuel ratio sensor |
| JPS5227696A (en) * | 1975-08-27 | 1977-03-02 | Hitachi Ltd | Oxygen concentration measuring instrument |
| US4098650A (en) * | 1976-11-08 | 1978-07-04 | Thermo-Lab Instruments, Inc. | Method and analyzer for determining moisture in a mixture of gases containing oxygen |
| JPS5777954A (en) * | 1980-10-31 | 1982-05-15 | Fuji Electric Co Ltd | Hydrogen sensor |
| JPS5850458A (en) * | 1981-09-22 | 1983-03-24 | Toyo Soda Mfg Co Ltd | Galvanic cell type humidity sensor |
| JPS59125055A (en) * | 1983-01-05 | 1984-07-19 | Toyo Soda Mfg Co Ltd | High temperature hydrogen sensor |
-
1984
- 1984-06-11 JP JP59120464A patent/JPS60263853A/en active Pending
-
1985
- 1985-05-30 GB GB08513589A patent/GB2161605A/en not_active Withdrawn
- 1985-06-05 FR FR8508493A patent/FR2565690B1/en not_active Expired
- 1985-06-11 DE DE19853520908 patent/DE3520908A1/en not_active Ceased
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1469698A (en) * | 1973-05-23 | 1977-04-06 | Bosch Gmbh Robert | Oxygen sensors for exhaust gases |
| GB1483763A (en) * | 1973-10-06 | 1977-08-24 | Bosch Gmbh Robert | Electrochemical sensors |
| GB2009412A (en) * | 1977-12-05 | 1979-06-13 | Bendix Autolite Corp | Electrochemical gas constituent sensor |
| GB2017926A (en) * | 1978-04-03 | 1979-10-10 | Gen Motors Corp | Heated solid electrolyte oxygen sensor |
Also Published As
| Publication number | Publication date |
|---|---|
| DE3520908A1 (en) | 1985-12-12 |
| FR2565690A1 (en) | 1985-12-13 |
| GB8513589D0 (en) | 1985-07-03 |
| JPS60263853A (en) | 1985-12-27 |
| FR2565690B1 (en) | 1987-10-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4559126A (en) | Electrochemical device | |
| US4569748A (en) | Oxygen sensor | |
| US20080202943A1 (en) | Particulate Sensor and Method For Operating a Particulate Sensor | |
| CA1308781C (en) | Oxygen sensor device | |
| EP0706046A1 (en) | Flat plate sensor with a robust package design | |
| US4575410A (en) | Solid state electrode system for measuring pH | |
| SU1142783A1 (en) | Gas analysis device having solid electrolyte based galvanic cells | |
| US4476008A (en) | Oxygen concentration-sensing device and the method of producing the same | |
| US8097137B2 (en) | Gas sensor element and gas sensor | |
| JP5996981B2 (en) | Gas sensor element and gas sensor | |
| WO2020246174A1 (en) | Method for manufacturing gas sensor element, gas sensor element, and gas sensor | |
| US4399017A (en) | Gas sensor having lead wires extending in insulating and hermetically sealed holder | |
| JPH02503594A (en) | Terminal section of oxygen measuring device | |
| JPS5728241A (en) | Gas component detector | |
| GB2161605A (en) | Apparatus for continuously measuring concentration of hydrogen or steam contained in gas | |
| US10345257B2 (en) | Gas sensor | |
| RU2120624C1 (en) | Electrochemical sensor of concentration of hydrogen in gas and liquid mixtures | |
| JPS636677Y2 (en) | ||
| JP5035853B2 (en) | Oxygen concentration sensor, method for forming the same, and method for measuring oxygen concentration in high-temperature high-pressure water | |
| RU2694275C1 (en) | Electrochemical device for oxygen dosing in gas medium and simultaneous control of oxygen content of gas at inlet and outlet of oxygen pump | |
| JPS6158779B2 (en) | ||
| JPH08220064A (en) | Carbon dioxide gas sensor | |
| JPS5819554A (en) | Oxygen concentration detector | |
| US20200319156A1 (en) | NOx SENSOR ELEMENT AND NOx SENSOR | |
| AU637621B2 (en) | Electrochemical sensor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |