Is natural gas LPG or LNG?

You must have heard of the terms Liquified Petroleum Gas and Liquified Natural Gas. But have you ever wondered how they differ? LPG and LNG are common energy solutions that are utilized globally for various purposes. Even though they sound similar, they are very different in their composition which ends up making them distinct from one another in terms of density, energy content, storage criteria, combustion modes, as well as safe methods of delivery. In this article, let’s dive into the nuances of each of these criteria and assess the differences systematically. 

What is Natural Gas?

Natural Gas is primarily composed of methane. The methane molecule consists of one carbon atom and four hydrogen atoms. Since all the valence electrons of Carbon are occupied, this makes this molecule inherently chemically stable. 

LNG Production

This intriguing energy source takes shape when natural gas is subjected to a deep chill, cooling down to a frigid -161ºC at atmospheric pressure. The result is a clear, colorless, non-toxic cryogenic liquid.

Freight Modes

LNG is stored in spherical tanks in its liquid form. This allows for safe storage on ships or road trains. LNG facilitates easy transportation over long distances.

LNG Traits

Physical Traits

LNG is colorless, odorless, and non-toxic, which earns it significant eco-friendly credentials. Additionally, it’s non-corrosive, making it the preferred fuel for operating sensitive and expensive equipment and machinery.

Spatial Efficiency

One of LNG’s standout features is its space efficiency. It occupies a mere 1/600th of the volume of natural gas, making it a remarkably compact alternative.

Environmental Benefits

LNG is an eco-friendly alternative to petroleum-based energy sources. Especially in sectors such as mining, marine, and industrial operations. As LGN burns in a very clean manner, the adoption of these in mining operations has increased. There is also another added advantage as it is more economical compared to diesel. It not only helps reduce operational costs but also contributes to mitigating the environmental impact associated with traditional oil-derived fuels.

What about Petroleum Gas?

The composition of petroleum gas is that of propane and butane. Even though these are flammable hydrocarbons, their chemical properties vary a lot. 

The Rise of LPG

Technavio, a London-based market research and advisory company predicts that the increased utilization of LPG across a wide spectrum of applications will amplify demand. Their forecast suggests that the global market for LPG cylinders could exceed a staggering US$313 million by 2023.

Propane vs. Butane: The Fundamental Differences

Boiling Point

Propane has a very low boiling point at -42°C.  Whereas Butane’s is -0.4°C. This difference makes Propane the better choice for colder climates.

Vapor Pressure

Propane has a vapor pressure of approximately four times that of Butane. This makes Propane suitable for external storage, even in chilly weather conditions. 

Weight 

Both Butane and Propane are heavier than air, with Propane weighing in at 1.898 kg/m³ and Butane at 2.5436 kg/m³, while air stands at 1.225 kg/m³. 

So, LPG is basically available in two forms as discussed. 

Freight Mode

LPG often arrives at your doorstep in gas cylinders. That’s the reason that most residential homes have access to LPG as an energy source mainly for cooking purposes. Moreover, since LPG is portable, it is liked by travelers and is a mandatory item on every adventurer’s list. Be it trekking or camping, the ease of usage of this energy source makes it a must to carry.

Applications

Many sectors utilize LPG. From heating appliances to fuels cooking equipment, and even propels vehicles. Most LPG was sourced from natural gas and oil production. However, with new technologies, LPG production is gradually transitioning towards renewable sources.

Environmental Impact: Propane and Butane as Green Alternatives

Propane and Butane, fortunately, emerged as clean-burning fuels, emitting fewer pollutants and harmful refrigerants. This inherent eco-friendliness that propane and butane have carries several advantages.

Lowering Harmful Emissions

Propane emits around 26% fewer greenhouse gases (GHGs) than gasoline in vehicles. It also outperforms fuel oil in furnaces, emitting 38% fewer GHGs, and reduces carbon dioxide (CO2) emissions by half compared to charcoal barbecues. It is an ideal choice for environmentally friendly household appliances.

Reducing Pollution

The environmental merits of Propane become even more apparent if you consider its emissions. It emits 60% less carbon monoxide (CO) than gasoline, a staggering 98% less particulate matter than diesel, and virtually no sulfur which is an active contributor to acid rain. Opting for Propane over conventional fuels means you are enabling pollution-free air!

Spill Hazard Mitigation

Propane gas cylinders are built to endure regular handling and pose no significant spill hazard. If there is a leak, Propane will swiftly dissipate into the atmosphere which minimizes environmental impact.

Fugitive Emissions

The term ‘fugitive emissions’ refers to gas escaping into the atmosphere before combustion. Since Propane is not a greenhouse gas, it leaves no adverse impact on the environment if it unintentionally gets released prior to combustion.

Differences Between LPG and LNG

While LPG and LNG share some commonalities, such as being gases at normal temperature and pressure points, they differ in crucial aspects:

Liquefaction Process

LPG is liquefied under light pressure, whereas LNG undergoes cryogenic liquefaction, involving exposure to extremely low temperatures.

Storage and Transportation

LPG is typically stored, shipped, and transported in tanks or cylinders. In contrast, LNG relies on purpose-built cryogenic tanks, and pipelines are the preferred mode of transport.

Global Accessibility

The need for cryogenic storage and associated infrastructure, including production plants, dispensing stations, and pipeline transport facilities, means that LNG may not be a viable option in many developing nations.

Thought Residue!

Understanding the differences between natural gas, LPG, and LNG helps you make informed choices. Each energy source has its unique attribute and caters to a range of needs from residential to industrial applications. It’s crucial to recognize that despite many variations, all three gases—Propane, Butane, and LPG—are fundamentally categorized as Liquefied Petroleum Gases whereas natural gas is composed of Methane that makes up LNG. As the global energy demands evolve, we can expect these two substances to remain relevant even in the realm of high-tech society.