Types of gas mixtures in cylinders for a gas stove
Have you ever tried to detect a gas leak in a kitchen by smell? And if there is no smell or is it poorly picked up? Agree that one who understands the main differences between gas mixtures and knows how to determine them feels more confident. To know liquefied gas in cylinders is what kind of gas and how it will behave in case of violation of the integrity of the gas duct, it is important. This is a security issue.
Each type of fuel has its own characteristics. Specific heat of combustion, color, smell, auto-ignition temperature - these are all signs by which we identify a substance. An important parameter is the molar mass. The gas distribution during leakage depends on this value: it will accumulate at the bottom, filling the basement, or, conversely, will rise.
The ability to understand balloon mixtures is the key to proper operation, the absence of fatal errors during replacement, disposal. In addition, knowledge of the theory will help to make a competent choice when buying. And this is already half the battle.
The content of the article:
Natural or liquefied - what's the difference?
When choosing a fuel source, the user can come across two concepts: natural gas and liquefied. The first, in most cases, is transmitted through urban trunk networks. Much less often it can be purchased in a compressed state in containers. The second is the traditional composition for propane and butane cylinders.
Natural gas characteristics
The main component is methane. It accounts for almost no less than 70%.
The remaining parts are distributed between heavy hydrocarbons:
- propane;
- butane;
- ethane;
- pentane.
In addition, the composition includes hydrogen, nitrogen, carbon dioxide and a small amount of hydrogen sulfide. It is important to know that gas produced in nature is devoid of smell and color. Therefore, it is customary to enrich natural gas in cylinders odorants - substances with a pungent odor.
In order to determine the leak, do not have to sniff. Due to its volatility, the compound instantly spreads indoors, quickly attracting attention.
Of the odorants, the most common is ethanethiol, which gives away rot or rotten eggs. In large quantities, this compound is toxic. In a low concentration, characteristic of the classical composition of a household gas mixture, it is absolutely harmless.
Benefits of LPG
Propane and butane mixed in different proportions act as liquefied gas. Under high pressure, these carbons turn into liquid and noticeably decrease in volume. The reverse process is possible with increasing temperature - heating entails the expansion of the substance. Therefore, cylinders for liquefied petroleum gases are manufactured strictly according to GOSTs and are filled no more than 85%.
The undeniable advantage of propane-butane gas is lightness. A cylinder filled with such a mixture will be several times lighter than a similar container with methane.
Other advantages:
- environmental Safety;
- strong specific odor - a useful indicator of leakage;
- low cost.
Properly tuned plate connected to the cylinderwith hydrocarbon gas, it will work without soot, give out even trickles of burning fuel.
Winter and summer mixes
Since the presence of only one 5-liter cylinder is allowed in residential premises, large-capacity containers are installed outside the house. Accordingly, the climatic conditions during use can be any. Taking this factor into account, gas compositions are created for the warm and cold season, more about which is written here.
What is the difference between seasonal versions?
Inside the cylinder, liquefied gas is in two aggregate states: liquid and gaseous. The intensity of filling the gas duct with the gaseous fraction directly depends on temperature: in heat, the indicator is higher than at low temperatures.
Correction of this situation is carried out by changing the proportions of propane and butane. The first is able to evaporate at 42 degrees below zero. The second loses this ability immediately after crossing the zero mark.
Therefore, in winter, the volume of propane increases. In summer, on the contrary, it decreases. This approach makes it possible to reduce the cost of summer versions due to cheaper butane and ensure the effectiveness of winter ones.
Climate calculation
In determining the recommended proportions, the average strip of Russia was taken as a reference point. The minimum propane content for the winter version is limited to 70%. In the summer version, a 50 percent content is permissible.
Composition for other regions is carried out taking into account remoteness from the middle zone, climatic features. This should be done by specialists from licensed organizations.
Universal option for any temperature
The correct functioning of portable gas systems in a wide temperature range is characteristic for the combination of propane, isobutane and butane. Having different combustion temperatures, these substances made the complex composition as versatile as possible.
Coloring and labeling of gas cylinders
Surprisingly, the world has not yet come to a unified system for labeling gas cylinders.Therefore, when choosing a fuel source abroad, it is necessary to study local rules. In Russia, all containers with gas mixtures used for cooking on the stove have a white transverse inscription on a plain red background.
All other information is on a metal plate - a kind of product passport. This is the service life, serial number, empty mass, date of issue and next certification, manufacturer’s trademark, test pressure.
Painting and labeling standards common for methane and propane-butane mixtures - only red cylinders with a white inscription are suitable for use in the kitchen. Other colors may mean that the tank is filled with nitrogen, argon, ammonia, helium, freon.
How to identify a leak?
The difference in the leakage of methane and propane-butane mixture is the smell. But in that, and in another case, the stench will make itself felt in the first place.
To detect the penetration of both compounds into the airspace, 4 methods are suitable:
- Definition by hand. Household gases are colder than air. Running a hand through the places of flange connections, joints of gas pipeline elements, it is easy to feel the outgoing chill.
- Using a soapy solution. Appearing bubbles on the treated surface signal a problem.
- Installation of a stationary sensor. Preferred are models that deliver not only a digital signal in the form of instrument readings, but also an audio one.
- Handheld Measurement.
The method for measuring the concentration of harmful compounds in the air using portable sensors depends on the composition of the gas in household cylinders installed in the kitchen or outside the boundaries of the housing.
When measuring propane / butane leakage, install the device at the lowest point in the room. A heavy mixture will fill the floor space first.
The situation is different with methane - this gas is twice as light as air. Therefore, during evaporation, it will move up. Accordingly, it will be necessary to take measurements under the ceiling.
How to calculate balloon fullness?
The fullness of the container with the mixture is easily determined by weight. To do this, you need to know the weight of the empty tank and the weight of the gas. Both values are always indicated on the metal passport of the product. It can be a rectangular plate or a disk around the valve. The sum of these two values is equal to the weight of the full tank. A decrease in the amount indicates fuel consumption.
The weight of the mixture of butane and propane depends on the selected proportion, since propane is a lighter gas. At zero temperature, one liter of a 1: 1 mixture will weigh 564 grams. The weight of one liter of methane under the same conditions will be equal to 710 grams.
The reasons for the prevalence of propane mixtures
Compositions of propane and butane are much more likely to become raw materials for filling household gas cylinders.
The reasons are simple:
- Propane is easier to liquefy. A pressure of 16 atmospheres is enough to influence it. Methane will become liquid only after exposure to 150 atmospheres.
- The low cost of producing liquefied gas compared to a methane mixture.
- Lower cylinder strength, which has a positive effect on price.
- Safety of use.
Using a tank with an internal pressure of 16 atmospheres is much safer. And this is an important selection criterion.
Disposal of gas cylinders
Compliance with the rules of safe disposal is mandatory for gas cylinders with any composition. They must be taken to specialized points of reception / exchange.Despite the fact that propane-butane gas is contained in the vessel at a lower pressure than methane, the possibility of an explosion remains. The reason is the high residual propane pressure.
The main motives for the independent opening of old containers are the use of empty containers for household purposes and the delivery of scrap metal. Experts advise to abandon such ideas or take the help of professionals. The main thing is to remember that an entire cylinder is never completely free from a gas mixture.
An excellent way out is to hand over the bottle to a private service company. As a rule, their prices significantly exceed the benefits of the delivery of capacity in scrap metal. An additional bonus is pickup, when representatives of the organization travel for equipment to the specified address.
Conclusions and useful video on the topic
In order not to make a mistake when choosing, you can focus on the color of the container. To connect to the gas stove, red cylinders with a white inscription are used:
The most popular composition used to fill household cylinders is a mixture of propane and butane. Properly selected proportions allow the effective use of the physical properties of both substances.
Please note that a cylinder with an inscription that does not meet the requirements must be taken out of service. Any attempt to paint over, change the name is a violation of the rules.
Maybe you have useful experience using gas cylinders for a gas stove, are you well versed in compositions, or have you ever managed to notice a leak on time? Write about this in the comments. Your experience can be invaluable to other users.