Question

something about CNG-a clean fuel

Answer 1

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Compressed natural gas (CNG) (methane stored at high pressure) is a fuel which can be used in place of gasoline (petrol), Diesel fueland propane/LPG. CNG combustion produces fewer undesirable gases than the fuels mentioned above. It is safer than other fuels in the event of a spill, because natural gas is lighter than air and disperses quickly when released. CNG may be found above oil deposits, or may be collected from landfills or wastewater treatment plants where it is known as biogas.

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