Methane-Content LNG refers to liquefied natural gas characterized by a high proportion of methane (CH₄), typically ranging from 85% to 99% depending on gas source, treatment depth, and liquefaction process. Natural gas is purified and cooled to approximately –162°C, transforming methane into a cryogenic liquid and reducing volume by nearly 600 times.
Higher methane concentration directly enhances combustion efficiency, flame stability, and energy predictability, making Methane-Content LNG ideal for power generation, industrial heating, gas engines, and transportation fuels.
Composition & Quality Profile
| Component | Typical Range |
|---|---|
| Methane (CH₄) | 85–99% |
| Ethane (C₂H₆) | 1–8% |
| Propane & Heavier HC | < 1% |
| Nitrogen (N₂) | < 1–3% |
| Carbon Dioxide (CO₂) | < 50 ppm |
| Moisture (H₂O) | < 1 ppm |
| Sulfur Compounds (H₂S) | < 4 ppm |
Higher methane levels deliver a higher methane number, stable calorific value, reduced engine knocking, and cleaner exhaust emissions.
Key Characteristics
High Methane Purity: Smooth ignition, stable flame, predictable performance.
Low Impurity Levels: Prevents corrosion, hydrate formation, and instability.
High Energy Density: Economical long-distance storage and transport.
Cryogenic Fuel: Stored at –162°C using vacuum-insulated systems.
Low Emissions: Minimal SOx, PM, and significantly lower CO₂.
Typical Physical & Mechanical Properties
| Property | Typical Value |
|---|---|
| Methane Content | 85–99% |
| Physical State | Cryogenic liquid |
| Appearance | Clear, colorless |
| Boiling Point | –162°C |
| Density (Liquid @ –160°C) | 430–470 kg/m³ |
| Energy Content | 21–23 MJ/L |
| Gross Calorific Value | 48–55 MJ/kg |
| Net Calorific Value | 45–50 MJ/kg |
| Methane Number | 70–90 |
| Flammability Range (Gas) | 5–15% in air |
| Auto-Ignition Temperature | ~540°C |
| Sulfur Content | < 4 ppm |
| Moisture Content | < 1 ppm |
Influence of Methane Content on Performance
Higher methane concentration provides superior knock resistance, stable Wobbe Index, predictable thermal output, reduced maintenance, and longer engine and burner life. For sensitive applications, high-methane LNG is preferred over ethane-rich blends.
Storage, Handling & Safety
Stored in double-wall cryogenic tanks with vacuum insulation, pressure relief systems, and boil-off gas management. LNG is non-toxic, non-corrosive, and non-flammable in liquid form. Flammability occurs only when vaporized within a 5–15% air mixture.
Applications of Methane-Content LNG
Power Generation: Gas engines, turbines, micro-grids
Industrial Heating: Boilers, furnaces, kilns
Transportation: LNG trucks, buses, marine propulsion, rail
Commercial Use: Campuses, hospitals, HVAC systems
Remote Energy: Mining sites, islands, off-grid industries
Advantages Over Lower-Grade LNG & Other Fuels
Cleaner combustion and lower emissions
Improved engine compatibility and reliability
Reduced fuel conditioning needs
Predictable energy performance
Supports decarbonization and ESG goals