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

Definitions

• the present invention relates to a method of adding a malodorant to a gas distributed to a point of consumption, the ambient surroundings of the distribution system or of the point of 5 consumption being made aware of the existence of a fire, explosion or other risk if, as a result of leakage, carelessness or by other means, the ambient air contains a certain concentration of the gas in question.
• gases which may be odorified according to the present invention, mention may be made of oxygen 0 which, if the air outside the distribution system and point of use is enriched with oxygen, may cause extremely severe fire or explosion accidents.
• combustion gases such as natural gas, propane, butane, town gas (also known as coal gas), and so on, which, on becoming mixed into the air, may also cause 5 fire and explosion accidents.
• odorless toxic gases or more or less inert gases are odorless toxic gases or more or less inert gases. In the event of major leakage, these latter may displace the oxygen of the air, with the result that the risk of suffocation becomes imminent.
• BACKGROUND ART 0 Finnish patent application No. 870146 describes a method of improvi-ng the method of adding a malodorant to oxygen gas so as to render the ambient surroundings aware of the existence of an explosion risk if oxygen enrichment of the air were to occur, by eliminating handling by the user of the toxic malodorant and those 5 risks of explosion implicit in the addition of malodorants.
• a concentrated gas so-called master gas
• 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 5 and 50 ppm.
• the master gas were to contain only oxygen and the malodorant, for example dimethyl sulphide, D S, 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.
• the malodorant for example dimethyl sulphide, D S
• 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 combustion gases such as town gas and propane etc., toxic gases, inert gases and others. SOLUTION
• the method 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 ercaptan, 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.
• an organic sulphur or other compound such as for example dimethyl sulphide, tetrahydrothiophene or methyl ercaptan
• 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 supplied 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.
• 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.
• 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 .
• 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.
• 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 0.04 per cent. This is of no consequence whatever in cases involving combustion gases.
• this concentration of carbon dioxide will not have any injurious effect either.
• 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.

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)

Applications Claiming Priority (3)

Publications (1)

Family

ID=25673941

Family Applications (1)

Country Status (4)

Cited By (8)

Citations (3)

• 1988
  • 1988-11-30 FI FI885571A patent/FI93270C/fi 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

Patent Citations (3)

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