Liquefied Petroleum Gas (LPG)

Liquefied Petroleum Gas (LPG), sometimes referred to as liquid petroleum gas or simply LP gas, is a fuel gas that contains a flammable mixture of hydrocarbon gases. These gases, primarily propane and butane, are used for a variety of purposes including heating, cooking, and as fuel in some vehicles.

Production and Composition

LPG is prepared by refining petroleum or "wet" natural gas. It is almost entirely derived from fossil fuel sources, either manufactured during the refining of petroleum (crude oil) or extracted from petroleum or natural gas streams as they emerge from the ground. Approximately 62% of LPG is extracted directly from natural gas, while the remaining 38% is produced by petroleum refineries from crude oil.

During the refining process, crude oil or natural gas is separated into its various components, which are then processed to produce various hydrocarbons. The LPG fraction consists of butane and propane. Global production of LPG reached over 292 million metric tons annually by 2015, with consumption levels close to 284 million metric tons annually.

Uses

LPG is a versatile energy source. Its uses include:

Domestic Sector: Widely used for cooking and heating. In winter, LPG mixtures contain more propane due to its lower boiling point compared to butane, which is favored in summer mixtures.
Industrial Applications: Utilized as a fuel for industrial heating and as a raw material in the chemical industry.
Automotive Fuel: Also known as autogas, LPG is used as a fuel in internal combustion engines, providing an alternative to gasoline and diesel.
Agricultural Use: Employed in crop drying and as a heat source for livestock housing.

Specifications

In the United States, LPG is sold in two main grades: commercial propane and HD-5. The Gas Processors Association and the American Society of Testing and Materials publish specifications for these grades.

Safety and Storage

LPG is stored in above-ground tanks, known as bottled gas or in large, pressurized containers. The gas is stored under pressure to maintain it in a liquid state. This makes it convenient for storage and transportation. However, due to its flammable nature, strict safety measures are necessary to prevent leaks and explosions.

Environmental Impact

As a byproduct of fossil fuel extraction, LPG contributes to carbon emissions. However, it burns cleaner compared to other fossil fuels like coal and oil, producing fewer particulates and greenhouse gases.