Compressed natural gas Compressed natural gas Compressed natural gas (CNG) (methane stored at high pressure) is a fuel which can be used in place of gasoline, diesel fuel and 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. Biomethane – cleaned-up biogas from anaerobic digestion or landfills – can be used. CNG is made by compressing natural gas, (which is mainly composed of methane, CH), to less than 1 percent of the volume it occupies at
Liquefied natural gas the calorific value. Due to the sensitivity of liquefaction facilities to sulfur and mercury elements, the gas being sent to the liquefaction process shall be accurately refined and tested in order to assure the minimum possible concentration of these two elements before entering the liquefaction plant, hence there is not much concern about them. However, the main concern is the heating value of gas. Usually natural gas markets can be divided in three markets in terms of heating value: There are some methods to modify the heating value of produced LNG to the desired level. For the purpose of increasing