The main constituent of petroleum gas is butane that it also contains smaller amounts of propane and erhane. Thus, we can say that petroleum gas ⛽ is a mixture of three hydrocarbons: butane, propane and ethane. Butane, propane and ethane, all burn readily producing a lot of heat. This makes petroleum gas very good fuel. Petroleum gas is obtained as a by- product in oil refineries from the fractional distillation of petroleum. It is also produced by the creaking of petrol.
Butane, propane and ethane are gases under ordinary pressure (atmospheric pressure) but they can be easily liquified under pressure. The petroleum gas which has been liquefied under pressure is called Liquefied Petroleum Gas (LPG).
Thus, liquefied petroleum gas (LPG) consists mainly of butane (alongwith smaller amounts of propane and ethane) which has liquefied by applying pressure. In other words, the domestic gas cylinders like Indane contain mainly butane, with smaller amounts of propane and ethane, under pressure.
Petroleum Gas is supplied in liquid form so that even a small cylinder many contain a good weight of the gas ⛽. A domestic gas cylinder contains about 14 kilograms of LPG. A strong smelling substance called ethyl mercaptan is added to LPG cylinder to help in the detection of gas leakage. Ethyl mercaptan has a foul smell resembling that of hydrogen suphide gas which can be easily detected.
The gas used for domestic cooking is called 'Liquefied Petroleum Gas' (LPG) because it is obtained from petroleum and it is liquified by compression before filling into the cylinders.
Our domestic gas ⛽ cylinder contain a mixture of liquefied butane, propane and ethane hydrocarbons under pressure. When we turn on knob of the gas cylinder, the pressure is released and the highly volatile LPG gets converted into gas. This gas goes into the burner of our cooking stove. When a burning matchstick is applied to the burner, the gas burns with a blue flame producing a lot of heat. This heat is used for cooking food.
Advantage of LPG
- LPG has a high calorific value. So, it a good fuel. The calorific value of LPG is about 50kj/g. That is, when 1 gram of LPG burns ina gas stove, it kilojoules of heat energy.
- LPG burns with a smokeless flame and so does not cause air pollution.
- LPG does not produce any poisonous gases on burning.
- LPG is easy to handle and convenient to store.
- LPG is very neat and clean domestic fuel.
Dangers of LPG
Though LPG is an extremely good domestic fuel but it can be dangerous too. LPG is a highly inflammable gas, that is, it catches fire easily. Any linkage of LPG. from the gas cylinder, stove or the rubber pipe (connecting the cylinder and stove) will from an explosive mixture with air in the kitchen. And on lighting the matchstick, an explosion will take place, the whole kitchen will be set on fire and the person working in the kitchen may get burnt. In fact, many such accidents occur quite often and should be avoided by observing a few precautions.
Precautions for using LPG
* Before lighting a matchstick we should make sure that there is no fuel ⛽ smell of the leaking gas in the kitchen, near the gas cylinder or gas stove. If we smell gas leakage on entering the kitchen, then the door and windows should be opened at once to allow the gas to escape. This is because, through LPG is not a poisonous gas, but when inhaled in large quantities, it is quite harmful and can even cause death ☠️. The gas cylinder, rubber tubing and gas stove should then be checked to find out the source of gas leakage. This gas should be used only when the leakage has been set right by the gas mechanic. We should never light a matchstick or a candle durning the leakage of kitchen.
* We should not use any hot flames like a kerosene lamp, kerosene stove or electric heater near the gas cylinder.
* We should never use a leaking gas cylinder. The Gas Agency should be informed and the leaking gas cylinder replaced at the earliest.
