GB2029717A - Mixing apparatus for use in calibrating a vapour monitoring device - Google Patents
Mixing apparatus for use in calibrating a vapour monitoring device Download PDFInfo
- Publication number
- GB2029717A GB2029717A GB7930822A GB7930822A GB2029717A GB 2029717 A GB2029717 A GB 2029717A GB 7930822 A GB7930822 A GB 7930822A GB 7930822 A GB7930822 A GB 7930822A GB 2029717 A GB2029717 A GB 2029717A
- Authority
- GB
- United Kingdom
- Prior art keywords
- mixing
- duct
- ethanol
- heating means
- vapour
- 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.)
- Granted
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Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/0004—Gaseous mixtures, e.g. polluted air
- G01N33/0006—Calibrating gas analysers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
- B01F23/10—Mixing gases with gases
- B01F23/12—Mixing gases with gases with vaporisation of a liquid
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
- G01N33/483—Physical analysis of biological material
- G01N33/497—Physical analysis of biological material of gaseous biological material, e.g. breath
- G01N33/4972—Determining alcohol content
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- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Physics & Mathematics (AREA)
- Combustion & Propulsion (AREA)
- Food Science & Technology (AREA)
- Medicinal Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Sampling And Sample Adjustment (AREA)
- Feeding, Discharge, Calcimining, Fusing, And Gas-Generation Devices (AREA)
Abstract
A portion of a duct (11) for gas is heated by means (4) upstream of a mixing chamber (5) and vapour is supplied from a volatile liquid stored in a storage chamber (10). Further heating means (9) heats the mixing chamber (5) and storage chamber (10) so that the vapour introduced into the mixing chamber (5) can be at the same temperature as gas flowing through the chamber (5). This enables the apparatus to provide a source of gas with a constant vapour concentration for use in calibrating a vapour-monitoring device. <IMAGE>
Description
SPECIFICATION
A mixing apparatus for the use in calibrating a vapour-monitoring device
This invention relates to a mixing apparatus for use in calibrating a vapour-monitoring device.
A common type of vapour-monitoring device is an ethanol-monitoring device, and an important application of ethanol-monitoring apparatus is the detection of ethanol in the breath of a person. If the ethanol content of a person's breath is above a predetermined certain countries at the present time provide for drastic measures to be taken against that person, for example an immediate ban on driving. Therefore the alcohol-monitoring device should always provide accurate measurement results. To ensure accurate results, the ethanol-vapour monitoring device needs to be calibrated.
With a vapour-monitoring device for the detection and quantitative determination of a vapour, more particularly the ethanol content in the breath of a person, it is known to effect calibration immediately prior to the device being used. for this purpose, a calibrating vapour having a specific and predetermined ethanol content in admixture with air or inert gas such as notrogen or helium is introduced into the device. The prepared calibrating vapour is stored in a pressure gas cylinder. In order to prevent any change resulting from condensation, its composition is selected such that the partial pressure therein is always lower than that of pure ethanol at the lowest operating temperature required. Furthermore, it is essential that there is no water vapour present in the sample. Water complicates calibration on account of the non-uniform formation of condensate.To produce the mixture and fill it into bottles is costly and presupposes a mixing device which operates with a degree of accuracy. It is inconvenient to carry the bottles about, and the storage available therein is limited. When tapping is carried out, separation of the mixture can occur with the result that the calibration concentration is no longer correct. (German Offenlegungsschrift 22 40 422).
A known calibration apparatus for ethanolmonitoring devices comprises a casing filled with an absorbent material saturated with an ethyl alcohol-containing solution. The casing is enclosed by a heating device which maintains it at a prescribed temperature. The casing is tightly sealed until the ethanol-monitoring device is calibrated or checked, so that it retains its alcohol content. For checking the alcohol-monitoring device, the casing is punctured at both ends and an alcohol-free gas, for example alcohol-free respiratory air, is blown through. The alcohol vapour combines with the alcohol-free gas, with the result that the vapours received by the monitoring device to form a simulated breath sample have a known concentration of alcohol.
Utilization of an appropriate, absorbent material, for example tarlatan, is to prevent liquid alcohol from being carried along bv the respiratory air.
The alcohol content of the simulated breath sample is a function of the temperature and also of other parameters. By changing the temperature various concentrations of alcohol ought to be able to be produced. For the user, it is not practical to ascertain, after the apparatus has been used, whether the filling is sufficient for another test.
Thus for multiple and extended calibrations of the alcohol-testing apparatus there is the need for the presence of fresh calibrating apparatuses. The space required for this is disadvantageous for mobile apparatuses. (German Auslegeschrift 23 51 909).
According to the present invention there is provided a mixing apparatus, suitable for use in calibrating a vapour monitoring device, the mixing apparatus comprising a duct having an inlet and an outlet, heating means for heating gas in the duct downstream on the inlet, a mixing chamber disposed in the duct between the heating means and the outlet, a storage chamber for storing a volatile liquid whose vapour is to be mixed in the mixing chamber with gas introduced into the duct via the inlet, which storage chamber is in communication with the mixing chamber, and further heating means for heating the mixing and storage chambers.
Preferably, the mixing apparatus includes a metering valve disposed between the inlet of the duct and the first-mentioned heating means, and a pump disposed between the inlet and the metering valve.
Advantageously the mixing chamber is adjacent the storage chamber and separated therefrom by a gas and vapour-permeable membrane.
It is to be appreciated that a mixing apparatus according to the present invention can be used for mixing the vapour of any volatile liquid with a gas, although the present invention is expected to be of particular use is producing a mixture of alcohol vapour and air.
In a mixing apparatus according to the present invention, with a constant temperature maintained in the mixing and storage chambers and with uniform moistening of the membrane equal diffusion of ethanol vapour through the membrane is obtained independently of the quantity of ethanol-water mixture stored in the storage chamber. It is thereby possible to produce precise ethanol-mixtures in a simple manner. The ethanolmonitoring devices can then be reliably calibrated with sufficient accuracy. The fact that the air, i.e.
the carrier gas, taken from the ambient air is heated to the temperature of the mixing chamber before it enters the same prevents errors due to temperature variations. The ethanol-water mixtures used thus should remain stable even during prolonged storage as they are not decomposed by bacteria.
Preferably the membrane has a thickness of 3 to 103 microns and a pore diameter of 0.01 to 10 microns.
The first heating means can be disposed around both the mixing and storage chambers for heating these chambers.
The mixing apparatus can also include an additional heating means disposed around the duct in a region between the mixing chamber and the outlet of the duct.
The first-mentioned heating means and, if present, the additional heating means may comprise tubular heaters disposed around the duct.
The storage chamber can be filled with fibrous material, or one or more blocks of porous material, in which a volatile liquid can be stored.
The mixing apparatus can be provided with the storage chamber filled with a mixture of water and ethanol. The water and ethanol mixture may comprise 20% water or 20% ethanol.
The present invention also provides a method of calibrating an ethanol vapour-monitoring device, the method comprising the steps of
(a) filling the storage chamber of mixing apparatus according to the present invention with a water and ethanol mixture,
(b) connecting the outlet of the duct of the mixing apparatus to an inlet of the ethanol vapourmonitoring device,
(c) pumping air through the mixing apparatus and thence into the ethanol vapour-monitoring device whilst maintaining the mixing and storage chambers at a constant temperature so that air leaving the mixing apparatus has a predetermined ethanol concentration, and
(d) calibrating the ethanol vapour-monitoring device from the known ethanol concentration in the air pumped through that device.
The storage chamber can be maintained at a temperature in the range from 25 to 700C.
For a better understanding of the present invention and to show more clearly how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawing which shows diagrammatically a mixing apparatus according to the present invention.
Although the present invention relates to a mixing apparatus for use in calibrating a vapourmonitoring device, the following description is directed to a mixing apparatus for use in calibrating an ethanol vapour-monitoring device.
The mixing apparatus has a duct 11 in which there is disposed, in the following order, a pump 2, aflow-volume regulator comprising a metering valve 3, first heating means 4 and a mixing device 7. The duct 11 has an inlet or suction part 1 for ambient air and an outlet 8 for connection to an ethanol vapour-monitoring device.
The mixing device 7 comprises a storage chamber 10 and a mixing chamber 5. The chambers 5 and 10 are separated from one another by a gas and vapour-permeable membrane 6. The mixing device 7 is enclosed by further heating means 9. The mixing chamber 5 has an inlet 12 and an outlet 13. Downstream of the inlet 13, additional heating means 14 are provided around the duct 1 The heating means 4 and 14 can comprise tubular heaters around the duct 11.
The storage chamber 10 can be filled with fibrous material or one or more blocks of porous
material in which ethanol or a water and ethanol
mixture can be absorbed and consequently the
apparatus does not have to be disposed in use, in a particular orientation.
In use, the storage chamber 10 is filled with ethanol or a mixture of ethanol and water and the outlet 8 is connected to the inlet of an ethanol vapour-monitoring device. The pump 2 is then operated to draw ambient air through the inlet 1
and pump it through the duct 11 to the ethanol vapour monitoring-device. The heating means 4 heats the air to a predetermined temperature, for example, 400 C, and the air then flows to the mixing chamber 5. Alcohol vapour diffuses through the membrane 6 and mixes with the air in the mixing chamber 5. The heating means 9 maintains the mixing device 7 at a predetermined temperature in the range, for example, from 25 to 70no. The heating means 4 and 9 can be controlled so that the air passing into the mixing chamber 5 through the inlet 12 is at substantially the same temperature as vapour passing through the membrane 6; this should ensure that the ethanol content of air leaving the mixing chamber 5 through the exit 13 is uniform and is not affected by temperature fluctuations. The additional heating means 14 maintains the temperature of the air and ethanol mixture and prevents condensaticn in the duct 11. The air, with a known ethanol concentration, then passes into the ethanol vapour-monitoring device which can then be calibrated.
Claims (30)
1. A mixing apparatus, suitable for use in calibrating a vapour-monitoring device, the mixing apparatus comprising a duct having an inlet and an outlet, heating means for heating gas in the duct downstream of the inlet, a mixing chamber disposed in the duct between the heating means and the outlet, a storage chamber for storing a volatile liquid whose vapour is to mixed in the mixing chamber with gas introduced into the duct via the inlet, which storage chamber is in communication with the mixing chamber, and further heating means for heating the mixing and storage chambers.
2. An apparatus as claimed in claim 1, including a metering valve disposed between the inlet of the duct and the first-mentioned heating means.
3. An apparatus as claimed in claim 2, including a pump disposed between the inlet and the metering valve.
4. An apparatus as claimed in claim 1, 2 or 3, wherein the mixing chamber is adjacent the storage chamber and separated therefrom by a gas and vapour-permeable membrane.
5. An apparatus as claimed in claim 4, wherein the membrane has a thickness of 3 to 103 microns and a pore diameter of 0.01 to 10 microns.
6. An apparatus as claimed in claim 4 or 5, wherein the further heating means is disposed around both the mixing and storage chambers for heating those chambers.
7. An apparatus as claimed in any preceding claim, which also includes an additional heating means disposed around the duct in a region between the mixing chamber and the outlet of the duct.
8. An apparatus as claimed in any preceding claim, wherein the first-mentioned heating means and, if present, the additional heating means, comprise tubular heaters disposed around the duct.
9. An apparatus as claimed in any preceding claim, wherein the storage chamber is filled with fibrous material in which a volatile liquid can be absorbed.
10. An apparatus as claimed in any one of claims 1 to 8, wherein the storage chamber includes one or more blocks of porous material in which a volatile liquid can be stored.
11. An apparatus as claimed in any preceding claim wherein the storage chamber is filled with a volatile liquid comprising a mixture of water and ethanol.
12: An apparatus as claimed in claim 11, wherein the mixture comprises 20% water.
13. An apparatus as claimed in claim 11, wherein the mixture comprises 20% ethanol.
14. An apparatus substantially as hereinbefore described with reference to, and as shown in, the accompanying drawing.
1 5. A method of calibrating an ethanol vapourmonitoring device, the method comprising the steps of:
(a) filling the storage chamber of a mixing apparatus as claimed in any of claims 1 to 14 with a water and ethanol mixture,
(b) connecting the outlet of the duct of the mixing apparatus to an inlet of the ethanol vapourmonitoring device,
(c) pumping air through the mixing apparatus and thence into the ethanol vapour-monitoring device whilst maintaining the mixing and storage chambers at a constant temperature so that air leaving the mixing apparatus has a predetermined ethanol concentration, and
(d) calibrating the ethanol vapour-monitoring deviced from the known ethanol concentration in the air pumped through that device.
1 6. A method according to claim 15, wherein the storage chamber is maintained a temperature in the range from 25 to 700C.
17. In combination, a vapour-monitoring device and a mixing apparatus according to any of claims 1 to 14.
New claims or amendments to claims filed on 17/12/79.
SUPERSEDED CLAIMS
NEW CLAIMS 18-30
18. A mixing apparatus, suitable for use in calibrating a vapor-monitoring device, the mixing apparatus comprising a duct having an inlet and an outlet; a pump in the duct; a metering valve in the duct; a first heating means disposed around the duct and nearer to the outlet than the pump or metering valve; a mixing chamber communicating with the duct and disposed between the first heating means and the outlet; a storage chamber for storing a volatile liquid whose vapour is to mixed in the mixing chamber with gas introduced into the duct via the inlet, which storage chamber is in communication with the mixing chamber via a gas and vapour permeable membrane; and further heating means for heating the mixing and storage chambers; there being no connection, except via the duct itself, between any region of the duct downstream (in terms of the intended direction of flow of gas in the duct from the inlet to the outlet) of the mixing chamber and any region of the duct upstream of the mixing chamber, the arrangement being such that, in use, gas is pumped by the pump through the mixing chamber once only, with the first heating means and the further heating means operating to maintain the gas flowing via the duct into the mixing chamber and the vapour entrained in the mixing chamber, respectively, at an equal temperature.
19. An apparatus as claimed in claim 18, wherein the membrane has a thickness of 3 to 103 microns and a pore diameter of 0.01 to 10 microns.
20. An apparatus as claimed in claim 18 or 19, wherein the further heating means is disposed around both the mixing and storage chambers for heating those chambers.
21. An apparatus as claimed in claim 18, 19 or 20, which also includes an additional heating means disposed around the duct in a region between the mixing chamber and the outlet of the duct.
22. An apparatus as claimed in claim 18, 19, 20 or 21, wherein the first heating means and, if present, the additional heating means, comprise tubular heaters disposed around the duct.
23. An apparatus as claimed in any one of claims 18 to 22, wherein the storage chamber is filled with fibrous material in which a volatile liquid can be absorbed.
24. An apparatus as claimed in any one of claims 1 8 to 22, wherein the storage chamber includes one or more blocks of porous material in which a volatile liquid can be stored.
25. An apparatus as claimed in any one of claims 1 8 to 24, wherein the storage chamber is filled with a volatile liquid comprising a mixture of water and ethanol.
26. An apparatus as claimed in claim 25, wherein the mixture comprises 20% water.
27. An apparatus as claimed in claim 25, wherein the mixture comprises 20% ethanol.
28. A method of calibrating an ethanol vapourmonitoring device, the method comprising the steps of:
(a) filling the storage chamber of a mixing apparatus as claimed in any of claims 1 8 to 27 with a water and ethanol mixture,
(b) connecting the outlet of the duct of the mixing apparatus to an inlet of the ethanol vapourmonitoring device.
(c) pumping air through the mixing apparatus once only and thence into the ethanol vapour-monitoring device whilst maintaining the mixing and storage chambers at a constant temperature equal to that of air flowing into the mixing chamber so that air leaving the mixing apparatus has a predetermined ethanol concentration, and
(d) calibrating the ethanol vapour-monitoring device from the known ethanol concentration in the air pumped through that device.
29. A method according to claim 28, wherein the storage and mixing chambers are maintained a temperature in the range from 25 to 700C.
30. In combination, a vapour-monitoring device and a mixing apparatus according to any one of claims 18 to 27.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE2839154 | 1978-09-08 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB2029717A true GB2029717A (en) | 1980-03-26 |
| GB2029717B GB2029717B (en) | 1982-08-11 |
Family
ID=6048987
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB7930822A Expired GB2029717B (en) | 1978-09-08 | 1979-09-05 | Mixing apparatus for use in calibrating a vapour monitoring device |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2029717B (en) |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0255232A1 (en) * | 1986-08-01 | 1988-02-03 | Colin Hammond | Mist making machine |
| EP0411500A1 (en) * | 1989-08-02 | 1991-02-06 | Hoechst Aktiengesellschaft | Devive for making gas vapour mixtures |
| WO1997014947A2 (en) * | 1995-10-17 | 1997-04-24 | Lion Laboratories Plc | Container for calibration fluid |
| WO2001025781A2 (en) * | 1999-10-04 | 2001-04-12 | Technische Universität München | Device for producing a single or multiple component test gas from organic-chemical substances |
| DE10121458A1 (en) * | 2001-05-02 | 2002-11-14 | Siegfried Jahnke | Apparatus to diffuse purge gas, in carrier gas for calibration of gas analyzers, features diffusion chamber inserted into carrier gas flow tube as diffusion medium |
| DE102009000391A1 (en) * | 2008-12-15 | 2010-06-17 | BAM Bundesanstalt für Materialforschung und -prüfung | Method and device for producing complex gas mixtures |
| WO2014003674A1 (en) * | 2012-06-27 | 2014-01-03 | Alco Systems Sweden Ab | Cartridge based breath alcohol calibration device |
| WO2015085006A1 (en) * | 2013-12-05 | 2015-06-11 | Lifeloc Technologies, Inc. | Vaporized fluid detector calibration device |
| CN105642183A (en) * | 2016-01-22 | 2016-06-08 | 保定市北方特种气体有限公司 | Preparation method of electric light source gas containing dibromomethane |
| US20210109072A1 (en) * | 2016-09-09 | 2021-04-15 | Consumer Safety Technology, Llc | Reference gas management in a breath alcohol calibration station |
| US11971395B2 (en) | 2016-09-09 | 2024-04-30 | Consumer Safety Technology, Llc | Secure data handling in a breath alcohol calibration station |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10458975B1 (en) | 2013-07-31 | 2019-10-29 | 1A Smart Start, Llc | Calibration device and method for calibrating an ignition interlock device |
| CN108517179B (en) * | 2018-04-12 | 2020-08-25 | 广东汇源防水工程有限公司 | Production and processing technology of polyurethane waterproof coating |
-
1979
- 1979-09-05 GB GB7930822A patent/GB2029717B/en not_active Expired
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0255232A1 (en) * | 1986-08-01 | 1988-02-03 | Colin Hammond | Mist making machine |
| EP0411500A1 (en) * | 1989-08-02 | 1991-02-06 | Hoechst Aktiengesellschaft | Devive for making gas vapour mixtures |
| WO1997014947A2 (en) * | 1995-10-17 | 1997-04-24 | Lion Laboratories Plc | Container for calibration fluid |
| WO1997014947A3 (en) * | 1995-10-17 | 1997-06-19 | Lion Lab Plc | Container for calibration fluid |
| WO2001025781A3 (en) * | 1999-10-04 | 2002-02-07 | Univ Muenchen Tech | Device for producing a single or multiple component test gas from organic-chemical substances |
| DE19947609C1 (en) * | 1999-10-04 | 2001-05-03 | Univ Muenchen Tech | Device for generating single or multi-component test gas for organic chemical substances |
| WO2001025781A2 (en) * | 1999-10-04 | 2001-04-12 | Technische Universität München | Device for producing a single or multiple component test gas from organic-chemical substances |
| DE10121458A1 (en) * | 2001-05-02 | 2002-11-14 | Siegfried Jahnke | Apparatus to diffuse purge gas, in carrier gas for calibration of gas analyzers, features diffusion chamber inserted into carrier gas flow tube as diffusion medium |
| DE102009000391A1 (en) * | 2008-12-15 | 2010-06-17 | BAM Bundesanstalt für Materialforschung und -prüfung | Method and device for producing complex gas mixtures |
| WO2014003674A1 (en) * | 2012-06-27 | 2014-01-03 | Alco Systems Sweden Ab | Cartridge based breath alcohol calibration device |
| US9207223B2 (en) | 2012-06-27 | 2015-12-08 | Alco Systems Sweden Ab | Cartridge based breath alcohol calibration device |
| WO2015085006A1 (en) * | 2013-12-05 | 2015-06-11 | Lifeloc Technologies, Inc. | Vaporized fluid detector calibration device |
| CN105642183A (en) * | 2016-01-22 | 2016-06-08 | 保定市北方特种气体有限公司 | Preparation method of electric light source gas containing dibromomethane |
| US20210109072A1 (en) * | 2016-09-09 | 2021-04-15 | Consumer Safety Technology, Llc | Reference gas management in a breath alcohol calibration station |
| US11971395B2 (en) | 2016-09-09 | 2024-04-30 | Consumer Safety Technology, Llc | Secure data handling in a breath alcohol calibration station |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2029717B (en) | 1982-08-11 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |