Liquefied Petroleum Gas
Liquefied Petroleum Gas (LPG) is a flammable mixture of gases, primarily propane and butane, that is produced as a by-product during the petroleum refining process. Known for its high caloric value and clean burning characteristics, LPG is widely utilized as a fuel source for domestic heating, cooking, and automotive applications. It is stored under pressure in specialized canisters, allowing for easy transport and use. Although LPG offers several advantages, such as efficiency and reduced greenhouse gas emissions compared to other fossil fuels, it is generally more expensive than natural gas and may not perform reliably in extremely low temperatures.
LPG originated from scientific investigations in the early 20th century, with Dr. Walter O. Snelling's discovery in 1910 marking its potential as an alternative fuel. Today, LPG is not only a common choice for residential heating, but it is also finding its way into modified vehicles as an environmentally friendly option. However, the limited infrastructure for LPG refueling stations presents challenges for widespread adoption. Overall, LPG serves as a versatile energy source with both benefits and limitations, appealing to those looking for efficient fuel alternatives.
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Liquefied Petroleum Gas
Liquefied petroleum gas (LPG) is a natural by-product of the petroleum refining process. Because LPG is extremely combustible and easily transportable, it is commonly used as fuel for lighters, heaters, and grills. In some cases, LPG is even used to power specially modified vehicles. Common LPGs include propane, butane, ethylene, and kerosene. These gases are normally stored in a compressed liquid state inside specialized canisters. When released, the LPG vapor is heavily combustible.
Background
Petroleum deposits have been discovered by explorers and researchers since before the sixteenth century. At first, oil was primarily used for illumination. It burned steadily at a controlled rate, which made it the ideal fuel for cheap lamps. At first, oil was made from whales. However, as whale populations declined from overhunting, oil produced from mined rock became the most common oil on the market.
In 1859, the Pennsylvania Rock Oil Company became the first to successfully drill for oil. After scientists studying small oil samples from the area declared that the oil would burn well, the company hired a former salt driller to find the source of the oil. It drilled more than sixty feet underground before striking oil, creating the first oil well.
From that point on, the oil industry grew exponentially. The first few wells were extremely popular, so countless other wells were quickly drilled. However, because of the increased amount of oil available on the market, prices began to fall. But once prices stabilized, the oil market continued to grow.
Many products are made from the oil found in wells. These include gasoline, oil-based lubricants, lamp oil, and diesel fuel. However, LPG was not discovered until 1910 by Dr. Walter O. Snelling. Snelling was investigating why gasoline evaporated so quickly, in an effort to find more efficient ways to transport the volatile fuel. Using a specialized distillery, Snelling realized that the evaporating gases were not the entirety of the gasoline, but specific, extremely light hydrocarbons now called LPGs.
The scientist quickly realized that LPGs could be used as an alternative fuel source. The gases were extremely flammable and could be easily transported. Within two years, LPG-powered stoves and heaters were sold across the United States.
Overview
LPGs are naturally occurring hydrocarbons found in natural gas and oil reserves. Because they do not occur in an isolated form in nature, they must be separated from other mined materials. This occurs during distillation.
To begin the process of isolating LPGs, crude oil is brought to a distillation tower. Crude oil refers to oil in its natural form, mined directly from an oil well. This crude oil is placed inside the distillation tower, a large, vertical structure. Workers then heat the crude oil past its boiling point, turning it into a gas. The gas quickly rises toward the top of the tower.
The crude oil turns back into a liquid state at varying rates, according to its various components. The rising oil vapor is forced through a large tower full of pipes, vents, and steel sieves. Different types of chemicals are trapped at different levels as they condense. Because the oil's components condense at different rates, they are quickly separated.
In some cases, the various floors of the distillation tower contain openings closed by valves. The valves are designed to open under specific amounts of pressure. The pressure corresponds to the type of chemical separated by the distillation tower. This method is considered more precise than the first method.
LPG is considered useful by the energy industry for a variety of reasons. First, LPG has a very high caloric value. This means that when burned, LPGs burn very hot and quickly. They also burn extremely cleanly. Most toxic chemicals, including greenhouse gases, are vaporized as the gas is burned. LPGs tend to be efficient, providing a large reaction with little waste. For the same reason, using LPGs to fuel machines is cheaper than using many other combustible gases.
LPG engines are compact, easily manufactured, and provide enough power for most machines. As a rule of thumb, if an engine or appliance can be powered by electricity, it can be powered by LPGs. Additionally, because large quantities of crude oil are being mined and distilled worldwide, the world market's current supply of LPG is extremely plentiful.
However, using LPG as a fuel source has some disadvantages. It is more expensive than natural gas and electricity. While it has a higher caloric value than most gases, its caloric value is lower than gasoline's, meaning it provides less power than gasoline. Lastly, LPG fuel does not handle various temperatures as well as gasoline, natural gas, or electricity. Because LPG needs to be in a gaseous form to ignite, it fails to reliably function in freezing temperatures.
Many common LPGs, including propane, isobutene, ethylene, and butane, are commonly utilized as heating fuels. They are used in torches, stoves, grills, hot water heaters, and furnaces. In other cases, LPGs are used in refrigeration and pressurization. Some automobile manufacturers have even begun to create consumer vehicles that run on LPGs. These vehicles are designed to provide an alternative energy source to gasoline and diesel, which are extremely damaging to the environment.
Engines fueled by LPG use its liquid, which is usually stored in a device similar to a traditional propane tank. They are filled at LPG stations, which function as traditional gas stations, and are refueled in a timeframe comparable to the average gasoline-powered vehicle. However, because of a lack of nationwide LPG stations, most LPG-powered vehicles sold in the United States are equipped to function on gasoline as well as LPG.
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