Methane-Content CNG refers to compressed natural gas with a very high proportion of methane (CH₄), typically ranging between 85% and 98%, processed and compressed to high pressure (200–250 bar) for use as a clean, efficient, and economical fuel.
Unlike LNG, which is liquefied at cryogenic temperatures, Methane-Content CNG is supplied and consumed in gaseous form, allowing direct use in engines, burners, boilers, and generators without cryogenic infrastructure.
High methane concentration significantly enhances combustion stability, energy efficiency, and emission performance, making Methane-Content CNG one of the most preferred fuels for automotive, industrial, commercial, and power-generation applications.
Composition & Quality Profile
Methane-Content CNG is derived from natural gas fields and undergoes multiple purification stages to achieve high methane purity and consistent fuel quality.
Typical Chemical Composition
Methane (CH₄): 85–98%
Ethane (C₂H₆): Trace–5%
Propane & heavier hydrocarbons: <1%
Nitrogen (N₂): <2%
Carbon Dioxide (CO₂): <3%
Hydrogen Sulfide (H₂S): <4 ppm
Moisture (H₂O): <1 ppm
Odorant: Mercaptan added for safety
Higher methane content ensures higher calorific value, better knock resistance, lower carbon intensity, and stable, predictable combustion.
Key Characteristics of Methane-Content CNG
High Methane Purity
Methane levels reaching up to 98% provide clean flame characteristics, uniform heat output, and minimal carbon deposits.
Environment-Friendly Fuel
Methane-rich CNG emits approximately 20–30% less CO₂ than petrol and diesel, negligible SOₓ emissions, up to 90% lower particulate matter, and significantly reduced NOₓ emissions.
High Compression without Liquefaction
Stored at 200–250 bar, Methane-Content CNG eliminates the need for cryogenic systems, reducing infrastructure complexity compared to LNG.
High Octane Rating
An octane number above 120 enables knock-free engine operation, higher compression ratios, and improved fuel efficiency.
Safe & Lightweight Fuel
CNG is lighter than air and disperses rapidly in open environments, reducing fire risk in case of leakage.
Typical Mechanical / Physical Properties
| Property | Typical Value |
|---|---|
| Methane Content | 85–98% |
| Physical State | Compressed gas |
| Storage Pressure | 200–250 bar |
| Density (at 250 bar) | 0.18–0.22 kg/L |
| Energy Content | 48–55 MJ/kg |
| Volumetric Energy | ~9–10 MJ/Nm³ |
| Octane Number | 120–130 |
| Auto-Ignition Temperature | ~540°C |
| Flammability Range | 5–15% in air |
| Burning Characteristics | Clean, smooth, low soot |
Refining & Processing Method
Methane-Content CNG is produced through controlled gas-processing steps:
Gas sweetening to remove hydrogen sulfide and sulfur compounds
CO₂ removal to improve calorific value and corrosion resistance
Dehydration to eliminate moisture and prevent freezing
Filtration and polishing to remove trace contaminants
High-pressure compression to 200–250 bar
Odorization using mercaptans for leak detection
This process ensures a stable, high-quality, engine-ready fuel.
Storage, Handling & Safety
Methane-Content CNG is stored in high-pressure steel or composite cylinders, cascade storage systems, and pipeline-based CGD networks.
Safety features include pressure relief devices (PRDs), excess-flow valves, gas detection systems, and odorization for early leak identification. Cylinders are rigorously tested for fire resistance, impact strength, and pressure cycling.
Applications of Methane-Content CNG
Automotive & Transport
Passenger vehicles, taxis, buses, fleet vehicles, light and heavy commercial vehicles
Industrial Applications
Boilers, steam generators, furnaces, ovens, textile, ceramic, and food-processing units
Commercial & Institutional
Hotels, hospitals, centralized kitchens, HVAC and space heating
Power Generation
Gas-engine-based captive power plants, backup generators, data centers
Remote & Off-Grid Use
Industrial parks without pipeline access, mining and construction sites
Advantages Over Other Fuels
Cleaner than diesel, petrol, LPG, and furnace oil
Lower fuel and maintenance costs
Longer engine and equipment life
Reduced carbon footprint
High safety margin
Stable long-term energy solution