CA2009716A1 - Method of adding a malodorant to gases - Google Patents
Method of adding a malodorant to gasesInfo
- Publication number
- CA2009716A1 CA2009716A1 CA002009716A CA2009716A CA2009716A1 CA 2009716 A1 CA2009716 A1 CA 2009716A1 CA 002009716 A CA002009716 A CA 002009716A CA 2009716 A CA2009716 A CA 2009716A CA 2009716 A1 CA2009716 A1 CA 2009716A1
- Authority
- CA
- Canada
- Prior art keywords
- gas
- consumer
- malodorant
- master
- distributed
- 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.)
- Abandoned
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
- C10L3/00—Gaseous fuels; Natural gas; Synthetic natural gas obtained by processes not covered by subclass C10G, C10K; Liquefied petroleum gas
- C10L3/003—Additives for gaseous fuels
- C10L3/006—Additives for gaseous fuels detectable by the senses
Landscapes
- Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Treating Waste Gases (AREA)
- Gas Separation By Absorption (AREA)
- Fats And Perfumes (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
The disclosure relates to a method of adding a malodorant to a consumer gas which is distributed to a consumer point, in order to render the surroundings aware of the existence of a risk of accident if consumer gas were to leak out into the air, employing such a process using a concentrated gas, master gas, that the malodorant does not condense during transport and storage of the master gas at low temperatures. The malodorant, in the form of an organic sulphur or other compound, is dissolved in liquid carbon dioxide or other condensable gas in a pressure vessel, in which there is obtained a solution which essentially comprises a gaseous phase and a liquid phase. The solution, the master gas, is withdrawn from the liquid phase, vaporized and added to the consumer gas which is distributed to the consumer.
The disclosure relates to a method of adding a malodorant to a consumer gas which is distributed to a consumer point, in order to render the surroundings aware of the existence of a risk of accident if consumer gas were to leak out into the air, employing such a process using a concentrated gas, master gas, that the malodorant does not condense during transport and storage of the master gas at low temperatures. The malodorant, in the form of an organic sulphur or other compound, is dissolved in liquid carbon dioxide or other condensable gas in a pressure vessel, in which there is obtained a solution which essentially comprises a gaseous phase and a liquid phase. The solution, the master gas, is withdrawn from the liquid phase, vaporized and added to the consumer gas which is distributed to the consumer.
Description
4 2 ~
The mixture of the solution, the master gas, consisting of malodorant dissolved in, for example, liquid carbon dioxide, into that gas which is to be distributed to the consumer, proceeds such that the liquid phase of the solution is withdrawn from the pressure vessel in which the solution is stored, is vapourized and mixed with the consumer gas in such proportions that the concentration of malodorant in the gas will lie between 5 and 50 ppm~ preferably approx. 20 ppm.
In the event that the solution with malodorant is to be supplied to a gas which is distributed to different points of consumption by means of a pipe network or a central gas supply system, a gas mixer of more or less conventional type is coupled in upstream of the inlet to the pipe network. In this mixer, the consumer gas and the vaporized solution are mixed to the desired proportion.
In the event that the consumer gas is distributed to the consumer in gas containers at high pressure, the vaporized solution is first fed into the container in such a volume that, when the consumer gas is thereafter filled to the desired pressure, the concentration of malodorant is at the desired level.
Hence, the consumer gas which is supplied with malodorant in accordance with the method described in the foregoing will include, in addition to the odoury vector, an insignificant concentration of the major component of the master gas, for example carbon dioxide. If the master gas has a malodorant concentration of, for example, 5% and admixture is effected with one part master gas to 2,500 parts consumer gas, the concentration of malodorant will be 20 ppm and the concentraticn of carbon dioxide 0.04 per cent. This is of no consequence whatever in cases involving combustion gases. For employment of oxygen in various industrial flame processes, such as welding, cutting and heating work, this concentration of carbon dioxide will not have any injurious effect either. The purity of the oxygen which is produced today often lies above the requirements in, for example, gas cutting, by a few tenths of a percentage units.
~ 9~ 6 so-called master gas, is produced by adding to pure oxygen gas a malodorant in a concentration of between 1,000 and 10,000 ppm. In a separate space discrete from the aforesaid compartment, the master gas is added to the oxygen gas which is distributed to the consumer in such a volume that the malodorant in the consumer gas is present in a concentration of between S and 50 ppm.
However, if the master gas were to contain only oxygen and the malodorant, for example dimethyl sulphide, DMS, problems may occur in filling the master gas containers. It may then be unavoidable that a certain part of the filling procedure will give rise to a concentration region in which the mixture is combustible, at least in a part of the gas container. The risk of ignition and explosion may then be imminent.
One method of obviating this risk is described in Finnish patent application 872278. This application thus discloses a method of producing a concentrated 9dS, master 9dS, which essentially consists of oxygen and a malodorant such as dimethyl sulphide. According to the method disclosed in this application, the container for the master gas is first filled with a mixture of dimethyl sulphide and nitrogen or helium gas. The concentration of the dimethyl sulphide then lies in the range of between 0.5 and 2.5%. Thereafter, pure oxygen gas is added until the desired working pressure, for instance 200 bar, is obtained in the gas container.
One drawback inherent in the master gas produced in accordance with the above-described methods is, however, that it may not be exposed during transport ~or storage to such low temperature that the malodorant condenses. With a master gas consisting of, for example, 0.2% dimeth~l sulphide, 9.8% helium or nitrogen and 90% oxygen at a pressure of 200 bar, condensation of the dimethyl sulphide will take place if the temperature falls below approx. 13 C. When the gas container is subsequently warmed to a temperature above 13 Cj a considerable time will elapse before the condensed dimethyl sulphide has returned to its gaseous form.
The mixture of the solution, the master gas, consisting of malodorant dissolved in, for example, liquid carbon dioxide, into that gas which is to be distributed to the consumer, proceeds such that the liquid phase of the solution is withdrawn from the pressure vessel in which the solution is stored, is vapourized and mixed with the consumer gas in such proportions that the concentration of malodorant in the gas will lie between 5 and 50 ppm~ preferably approx. 20 ppm.
In the event that the solution with malodorant is to be supplied to a gas which is distributed to different points of consumption by means of a pipe network or a central gas supply system, a gas mixer of more or less conventional type is coupled in upstream of the inlet to the pipe network. In this mixer, the consumer gas and the vaporized solution are mixed to the desired proportion.
In the event that the consumer gas is distributed to the consumer in gas containers at high pressure, the vaporized solution is first fed into the container in such a volume that, when the consumer gas is thereafter filled to the desired pressure, the concentration of malodorant is at the desired level.
Hence, the consumer gas which is supplied with malodorant in accordance with the method described in the foregoing will include, in addition to the odoury vector, an insignificant concentration of the major component of the master gas, for example carbon dioxide. If the master gas has a malodorant concentration of, for example, 5% and admixture is effected with one part master gas to 2,500 parts consumer gas, the concentration of malodorant will be 20 ppm and the concentraticn of carbon dioxide 0.04 per cent. This is of no consequence whatever in cases involving combustion gases. For employment of oxygen in various industrial flame processes, such as welding, cutting and heating work, this concentration of carbon dioxide will not have any injurious effect either. The purity of the oxygen which is produced today often lies above the requirements in, for example, gas cutting, by a few tenths of a percentage units.
~ 9~ 6 so-called master gas, is produced by adding to pure oxygen gas a malodorant in a concentration of between 1,000 and 10,000 ppm. In a separate space discrete from the aforesaid compartment, the master gas is added to the oxygen gas which is distributed to the consumer in such a volume that the malodorant in the consumer gas is present in a concentration of between S and 50 ppm.
However, if the master gas were to contain only oxygen and the malodorant, for example dimethyl sulphide, DMS, problems may occur in filling the master gas containers. It may then be unavoidable that a certain part of the filling procedure will give rise to a concentration region in which the mixture is combustible, at least in a part of the gas container. The risk of ignition and explosion may then be imminent.
One method of obviating this risk is described in Finnish patent application 872278. This application thus discloses a method of producing a concentrated 9dS, master 9dS, which essentially consists of oxygen and a malodorant such as dimethyl sulphide. According to the method disclosed in this application, the container for the master gas is first filled with a mixture of dimethyl sulphide and nitrogen or helium gas. The concentration of the dimethyl sulphide then lies in the range of between 0.5 and 2.5%. Thereafter, pure oxygen gas is added until the desired working pressure, for instance 200 bar, is obtained in the gas container.
One drawback inherent in the master gas produced in accordance with the above-described methods is, however, that it may not be exposed during transport ~or storage to such low temperature that the malodorant condenses. With a master gas consisting of, for example, 0.2% dimeth~l sulphide, 9.8% helium or nitrogen and 90% oxygen at a pressure of 200 bar, condensation of the dimethyl sulphide will take place if the temperature falls below approx. 13 C. When the gas container is subsequently warmed to a temperature above 13 Cj a considerable time will elapse before the condensed dimethyl sulphide has returned to its gaseous form.
3 ~3~ 3 OBJECT OF THE INVENTION
The object of the present invention is to realize a method of production for master gas according to which the above-outlined drawbacks are obviated and which may also be employed for odorization of other gases than oxygen, such as natural gas, other combusticn gases such as town gas and propane etc., toxic gases, inert gases and othersA
SOLUTION
The methnd according to the present invention is essentially characterized in that the malodorant in the form of an organic sulphur or other compound, such as for example dimethyl sulphide, tetrahydrothiophene or methyl mercaptan, is dissolved in carbon dioxide, propane, butane, sulphur hexafluoride, dinitrogen oxide or other condensable gas in a pressure vessel in which the solution is present substantially in the liquid phase; and that the solution, the master gas, is extracted from the liquid phase, is vapourized and added to the gas intended for odorization which is to be distributed to the consumer. The method according to the present invention is further characterized in that when the malodorant consists of dimethyl sulphide, this is employed in a concentration of between 1 and 15%; and that such a volume of the extracted vapourized solution is suppliecl to the consumer gas that the malodorant is present in a concentration of between 5 and 50 ppm.
The liquid gas, for example carbon dioxide, in which the malodorant is dissolved is stored at ambient temperature in a pressure vessel in that the malodorant, for example dimethyl sulphide, is also soluble in, for example, liquid carbon dioxide at low temperatures. No separation of the substances will take place even if the solution is cooled during transport and winter storage to such extreme temperatures as -40 C. The reason for this is that experiments have shown that the solubility of dimethyl sulphide in liquid carbon dioxide is greater than 5 per cent by volume throughout the entire temperature range of between -40 C and +50 C.
The object of the present invention is to realize a method of production for master gas according to which the above-outlined drawbacks are obviated and which may also be employed for odorization of other gases than oxygen, such as natural gas, other combusticn gases such as town gas and propane etc., toxic gases, inert gases and othersA
SOLUTION
The methnd according to the present invention is essentially characterized in that the malodorant in the form of an organic sulphur or other compound, such as for example dimethyl sulphide, tetrahydrothiophene or methyl mercaptan, is dissolved in carbon dioxide, propane, butane, sulphur hexafluoride, dinitrogen oxide or other condensable gas in a pressure vessel in which the solution is present substantially in the liquid phase; and that the solution, the master gas, is extracted from the liquid phase, is vapourized and added to the gas intended for odorization which is to be distributed to the consumer. The method according to the present invention is further characterized in that when the malodorant consists of dimethyl sulphide, this is employed in a concentration of between 1 and 15%; and that such a volume of the extracted vapourized solution is suppliecl to the consumer gas that the malodorant is present in a concentration of between 5 and 50 ppm.
The liquid gas, for example carbon dioxide, in which the malodorant is dissolved is stored at ambient temperature in a pressure vessel in that the malodorant, for example dimethyl sulphide, is also soluble in, for example, liquid carbon dioxide at low temperatures. No separation of the substances will take place even if the solution is cooled during transport and winter storage to such extreme temperatures as -40 C. The reason for this is that experiments have shown that the solubility of dimethyl sulphide in liquid carbon dioxide is greater than 5 per cent by volume throughout the entire temperature range of between -40 C and +50 C.
4 ~ 7~L~i The mixture of the solution, the master gas, consisting of malodorant dissolved -in, for example, liquid carbon dioxide, into that gas which is to be distributed to the consumer, proceeds such that the liquid phase of the solution is withdrawn from the pressure vessel in which the solution is stored, is vapourized and mixed with the consumer gas in such proportions that the concentration of malodorant in the gas will lie between 5 and 50 ppm, preferably approx. 20 ppm.
In the event that the solution with malodorant is to be supplied to a gas which is distributed to different points of consumption by means of a pipe network or a central gas supply system, a gas mixer of more or less conventional type is coupled in upstream of the inlet to the pipe network. In this mixer, the consumer gas an~ the vaporized solution are mixed to the desired proportion.
In the event that the consumer gas is distributed to the consumer in gas containers at high pressure, the vaporized solution is first fed into the container in such a volume that, when the consumer gas is thereafter filled to the desired pressure, the concentration of malodorant is at the desired level.
Hence, the consumer gas which is supplied with malodorant in accordance with the method described in the foregoing will include, in addition to the odoury vector, an insignificant concentration of the major component of the master gas, for example carbon diox;de. If the master gas has a malodorant concentration of, for example, 5% and admixture is effected with one part master gas to 2,500 parts consumer gas, the concentration of malodorant will be 20 ppm and the concentration of carbon dioxide 0.0~ per cent. This is of no consequence whatever in cases involving combustion gases. For employment of oxygen in various industrial flame processes, such as welding, cutting and heating work, this concentration of carbon dioxide will not have any injurious effect either. The purity of the oxygen which is produced today often lies above the requirements in, for example, gas cutting, by a few tenths of a percentage units.
~ r~3 7 Thus, the method described in the foregoing has realized a master gas which includes a malodorant in the form of an organic sulphur or other compound such as, for example, dimethyl sulphide and which may also be stored and transported at low temperatures without any risk of condensation of the malodorant.
The present invention should not be considered as restricted to that described above, many modifications being conceivable without departing from the spirit and scope of the appended Claims.
,
In the event that the solution with malodorant is to be supplied to a gas which is distributed to different points of consumption by means of a pipe network or a central gas supply system, a gas mixer of more or less conventional type is coupled in upstream of the inlet to the pipe network. In this mixer, the consumer gas an~ the vaporized solution are mixed to the desired proportion.
In the event that the consumer gas is distributed to the consumer in gas containers at high pressure, the vaporized solution is first fed into the container in such a volume that, when the consumer gas is thereafter filled to the desired pressure, the concentration of malodorant is at the desired level.
Hence, the consumer gas which is supplied with malodorant in accordance with the method described in the foregoing will include, in addition to the odoury vector, an insignificant concentration of the major component of the master gas, for example carbon diox;de. If the master gas has a malodorant concentration of, for example, 5% and admixture is effected with one part master gas to 2,500 parts consumer gas, the concentration of malodorant will be 20 ppm and the concentration of carbon dioxide 0.0~ per cent. This is of no consequence whatever in cases involving combustion gases. For employment of oxygen in various industrial flame processes, such as welding, cutting and heating work, this concentration of carbon dioxide will not have any injurious effect either. The purity of the oxygen which is produced today often lies above the requirements in, for example, gas cutting, by a few tenths of a percentage units.
~ r~3 7 Thus, the method described in the foregoing has realized a master gas which includes a malodorant in the form of an organic sulphur or other compound such as, for example, dimethyl sulphide and which may also be stored and transported at low temperatures without any risk of condensation of the malodorant.
The present invention should not be considered as restricted to that described above, many modifications being conceivable without departing from the spirit and scope of the appended Claims.
,
Claims (5)
1. A method of adding a malodorant to a consumer gas distributed to a consumption point, such as, for example, oxygen, natural gas, propane, town gas or other combustion gas, odorless toxic gas or more or less inert gas, in order to draw the attention of the surroundings to the existence of a risk of fire, explosion, poisoning, suffocation or other danger if, as a result of leakage, carelessness or by other means, the consumer gas is allowed into the atmosphere, concentrated gas containing a malodorant, master gas, being mixed with the consumer gas, characterized in that the malodorant, in the form of an organic sulphur compound such as, for example, dimethyl sulphide, tetrahydrothiophene or methyl mercaptan, is dissolved in a condensed gas in a pressure vessel, suitably carbon dioxide, propane, butane, sulphur hexafluoride or dinitrogen oxide, there being obtained a solution, master gas, essentially comprising a liquid phase and a gas phase; and that said solution is withdrawn from the liquid phase, is vaporized and is supplied to the consumer gas which is distributed to the consumer.
2. The method as claimed in Claim 1, characterized in that the malodorant in the master gas consists of dimethyl sulphide;
and that its concentration in the master gas lies between 1 and 15%.
and that its concentration in the master gas lies between 1 and 15%.
3. The method as claimed in Claim 2, characterized in that the master gas is added in such an amount that the concentration of dimethyl sulphide in the consumer gas lies in the range of between 5 and 50 ppm.
4. The method as claimed in Claims 2 and 3, in which the consumer gas is distributed to the consumer through a pipe system at relatively low pressure, characterized in that the vaporized dimethyl sulphide is, via a per se known type of gas mixer, supplied to the consumer gas before the consumer gas is led out into the pipe system.
5. The method as claimed in Claim 3, in which the consumer gas is distributed to the consumer in containers under high pressure, characterized in that the master gas is fed to the container before the compressed comsumer gas is filled into the container.
Priority Applications (6)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FI885571A FI93270C (en) | 1988-11-30 | 1988-11-30 | Process for adding odorant to oxygen gas |
| FI891595A FI92864C (en) | 1988-11-30 | 1989-04-03 | A method of adding a fragrance to oxygen gas |
| FI895583A FI895583A0 (en) | 1988-11-30 | 1989-11-22 | SAETT ATT TILLFOERA LUKTAEMNE TILL GASER. |
| AU46561/89A AU4656189A (en) | 1988-11-30 | 1989-11-30 | Method of adding an odorant to gases |
| PCT/SE1989/000698 WO1990006170A1 (en) | 1988-11-30 | 1989-11-30 | Method of adding an odorant to gases |
| CA002009716A CA2009716A1 (en) | 1988-11-30 | 1990-02-09 | Method of adding a malodorant to gases |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FI885571A FI93270C (en) | 1988-11-30 | 1988-11-30 | Process for adding odorant to oxygen gas |
| CA002009716A CA2009716A1 (en) | 1988-11-30 | 1990-02-09 | Method of adding a malodorant to gases |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2009716A1 true CA2009716A1 (en) | 1991-08-09 |
Family
ID=25673941
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002009716A Abandoned CA2009716A1 (en) | 1988-11-30 | 1990-02-09 | Method of adding a malodorant to gases |
Country Status (4)
| Country | Link |
|---|---|
| AU (1) | AU4656189A (en) |
| CA (1) | CA2009716A1 (en) |
| FI (1) | FI93270C (en) |
| WO (1) | WO1990006170A1 (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DK0533670T3 (en) * | 1990-05-22 | 1995-10-02 | Aga Ab | Addition of a smelly substance to oxygen gas and a suitable liquid odorization mixture |
| RU2083641C1 (en) * | 1992-06-16 | 1997-07-10 | Ага Актиеболаг | Method and apparatus for adding odorant to consumer gas |
| FR2712599B1 (en) * | 1993-11-19 | 1996-01-12 | Air Liquide | Composition comprising an inert gas. |
| SE9401827L (en) * | 1994-05-27 | 1995-05-22 | Erik Smaars Konsult Ab | Method and apparatus for adding odorant to a consumable gas flowing in a gas line |
| DE19748212B4 (en) * | 1997-10-31 | 2006-10-12 | Air Liquide Deutschland Gmbh | Odoration of inert gases |
| ITPD20060270A1 (en) * | 2006-07-04 | 2008-01-05 | Francesco Jamoletti | METHOD AND SYSTEM FOR ODORING A GAS |
| ES2827274T3 (en) * | 2015-10-26 | 2021-05-20 | Shell Int Research | Odorized methane fluids and processes for the production of odorized methane fluids and their use |
| DE102021133472A1 (en) | 2021-12-16 | 2023-06-22 | Messer Cutting Systems Gmbh | Odorization insert for expanding a gas supply system, gas supply system equipped with the odorization insert and method for odorizing a working gas |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL174659C (en) * | 1972-03-27 | 1984-07-16 | Pennwalt Corp | METHOD FOR ODORIZING LIQUEFIED, FLAMMABLE HYDROCARBON GAS. |
-
1988
- 1988-11-30 FI FI885571A patent/FI93270C/en not_active IP Right Cessation
-
1989
- 1989-11-30 WO PCT/SE1989/000698 patent/WO1990006170A1/en unknown
- 1989-11-30 AU AU46561/89A patent/AU4656189A/en not_active Abandoned
-
1990
- 1990-02-09 CA CA002009716A patent/CA2009716A1/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| FI93270B (en) | 1994-11-30 |
| FI885571A0 (en) | 1988-11-30 |
| WO1990006170A1 (en) | 1990-06-14 |
| FI885571A (en) | 1990-05-31 |
| AU4656189A (en) | 1990-06-26 |
| FI93270C (en) | 1995-03-10 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| FZDE | Discontinued |