LNG AND LPG

11/11/2024

LNG (Liquefied Natural Gas) and LPG (Liquefied Petroleum Gas) are two common types of fuel used today. This article will explore the differences between these two types of gas.

LNG - Liquefied Natural Gas: It is a liquid hydrocarbon product derived from natural gas with the main component being Methane (CH4). LNG is a gas product that is deeply cooled to -162°C. LNG occupies only 1/600 of the volume compared to natural gas at standard conditions (15°C, 1 atm), making it convenient for storage and transportation to distant plants with a capacity 2.4 times higher than CNG.

LPG - Liquefied Petroleum Gas: It is a hydrocarbon product with the main components being Methane (CH4) and Propane (CH3). Depending on customer needs, Methane and Propane are blended in different ratios (30:70 - 40:60 - 50:50). Under normal air temperature and pressure conditions, LPG is usually in a gaseous state, however, it is called liquefied petroleum gas because these gases can be liquefied when compressed (without the need for cooling) for convenient storage and transportation.

THE CHARACTERISTICS OF LNG AND LPG (heating value, density,...)

Characteristics	Unit	LNG	LPG
Main ingredients		Metan (CH4)	Metan (CH4) and Propane (CH3)
Density	kg/liter (H2O = 1 kg/liter)	0,41-0,5 kg/liter	0,51-0,56 kg/liter
Calorific value	Mj/ kg	55	50
Autoignition temperature (flash point)	^oC	540^oC	480^oC
Flammable range	% in air	5 - 15%	2.1 - 9.5%
Octane rating	_	~130	95 ~ 100

Octane rating is a standard measure of engine performance. The higher the octane rating, the more the fuel can withstand compression before it detonates (ignites).

In recent years, Vietnam has strongly shifted towards using low-emission fuels, aiming for a "green" industry. The energy sector structure has also undergone significant changes. As a result, LNG and LPG have become highly encouraged fuels due to their high combustion efficiency and low CO2 and toxic gas emissions.